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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 172-181 
    ISSN: 1436-6215
    Schlagwort(e): galactolipids ; phospholipids ; frozen storage ; parsley
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Während der Gefrierlagerung von thermisch nicht behandelten Blattgeweben laufen bei praxisüblichen Lagerungstemperaturen enzymatische Lipidabbaureaktionen ab, die schon nach wenigen Wochen zu einem weitgehenden oder vollständigen Verlust der nativen polaren Lipide führen. Diese von einer Geschmacksverschlechterung begleiteten Prozesse wurden am Beispiel von Petersilieblättern näher untersucht. Unter den Reaktionsprodukten befanden sich beträchtliche Mengen von 6-Acylmonogalaktosyldiglyceriden — entstanden durch Transacylierung aus Monogalaktosyldiglyceriden — sowie von Phosphatidsäure, deren Bildung durch Einwirkung von Phospholipase D auf Phospholipide zu erklären ist. Die vielfach angenommene Reaktionsfolge: Spaltung der Lipide durch Acylhydrolasen, Hydroperoxidation der gebildeten freien Fettsäuren durch Lipoxigenase und Zerfall der Hydroperoxide in Off-flavour-Komponenten spielt möglicherweise nur eine untergeordnete Rolle. Die Phospholipase D ist selbst bei −24
    Notizen: Summary Under the frozen storage at usual storage temperatures of leafy tissues not pretreated by heat, enzymatic lipid degradation reactions take place, which lead already after a few weeks to a considerable or complete loss of the native polar lipids. These degradation processes being accompanied by a deterioration of the flavour have been studied in greater detail in parsley leaves. Among the reaction products we found large amounts of 6-acylmonogalactosyl diglycerides (formed from monogalactosyl diglycerides by enzymatic transacylation) and phosphatidic acid (formed from phospholipids through phospholipase-D action). The generally assumed reaction sequence: formation of free fatty acids by acyl hydrolases followed by hydroperoxidation through lipoxygenase and degradation o f the hydroperoxides into off-flavour compounds may hence take place, if at all, only to a limited extent. Considerable phospholipase D as well as minor acyl transferase activities are still detected at −24
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 208-215 
    ISSN: 1436-6215
    Schlagwort(e): apricot seed kernels ; amino acid composition ; PER-data
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Hamawy apricot seed kernels (sweet), Amar apricot seed kernels (bitter) and treated Amar apricot kernels (bitterness removed) were evaluated biochemically. All kernels were found to be high in fat (42.2–50.91 %), protein (23.74–25.70 %) and fiber (15.08–18.02 %). Phosphorus, calcium, and iron were determined in all experimental samples. The three different apricot seed kernels were used for extensive study including the qualitative determination of the amino acid constituents by acid hydrolysis, quantitative determination of some amino acids, and biological evaluation of the kernel proteins in order to use them as new protein sources. Weanling albino rats failed to grow on diets containing the Amar apricot seed kernels due to low food consumption because of its bitterness. There was no loss in weight in that case. The Protein Efficiency Ratio data and blood analysis results showed the Hamawy apricot seed kernels to be higher in biological value than treated apricot seed kernels. The Net Protein Ratio data which accounts for both weight, maintenance and growth showed the treated apricot seed kernels to be higher in biological value than both Hamawy and Amar kernels. The Net Protein Ratio for the last two kernels were nearly equal.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 223-228 
    ISSN: 1436-6215
    Schlagwort(e): kwashiorkor ; glucose tolerance ; tryptophan loading
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 253-262 
    ISSN: 1436-6215
    Schlagwort(e): obesity ; JW/AH index method ; diabetes ; age-groups ; survey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die Verfasser haben eine Reihenuntersuchung für die Aufklärung der Obesitätsfälle in der Kinderbevölkerung des Bezirks Monor (Komitat Pest) durchgeführt. Das Körpergewicht und die Körperlänge von 12 751 Kindern (3–18 Jahre alt) wurden gemessen. Mit der IW/AH-(Idealgewicht/aktuelle Körperlänge-)Indexmethode wurden 705 (5,3 %) Kinder übergewichtig gefunden. Mit Fragebogenmethode wurde geklärt, daß in den Familien von 784 Kindern Diabetes vorkommt. Unter diesen wurden 66 Obesitätsfälle unterschieden. Das Prozentverhältnis ist in dieser Gruppe mit 8,4 % viel höher als in der allgemeinen Population. Die größte Zahl der Obesitätsfälle wurde im Pubertätsalter gefunden. Bei den Kindern mit einer Familiengeschichte für Diabetes war diese Zahl in dem Alter von 14 bis 18 Jahren am größten. Die spezielle Untersuchung und ärztliche Beratung dieser Kinder ist im Gange.
    Notizen: Summary Authors conducted the weight-height measurements of 12,751 children in the district of Monor on the basis of the IW/AH index and found 705 obese children. Childhood obesity rate of the district was 5.53 %. The questionnaires sent to the affected children's families revealed diabetes in the families of 784 children, 66 of whom were obese, which is 8.4 % -much higher than the population's value. The highest obesity rate was found in puberty, while in children with a family background for diabetes this value was found in 14–18 years of age. The groups investigated are given special nursing. Authors express thanks to all the persons who contributed to carry out the measurements.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 275-282 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Ten protein-rich food mixtures were suggested. They are based on popular dishes which could be prepared simply at home. Such mixtures were prepared from seeds or legumes available in the local markets at reasonable prices. These ingredients are polished rice, decorticated lentils, defatted sesame flour, whole or roasted chick peas (dehulled), maize bread, sun flour kernels, fenugreek seeds, wheat (whole grains or parboiled grains), white wheat flour, defatted peanut flour, defatted sesame flour and dry yeast. The protein content of such food mixtures ranged from 17.7 to 23.2 %, which is in agreement with recommended values. Defatted sesame flour was incorporated in most of the mixtures in order to correct for their sulphur-containing amino-acids as it is already known that sesame is a rich source of sulphur-containing amino acids in comparison to other vegetable sources. Further investigations are going on to determine the nutritive value of the formulated mixtures before feeding them to the children.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 229-232 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 233-246 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary A meeting report is given (Annual Symposium on Fundamental Cancer Research, Houston, and International Congress of Nutrition, San Diego) which mainly deals with cancerogenesis: The role of retinoids as inhibitors, and the role of pyrolysis products as promoter of cancerogenesis, both essentially active in the tumor promotion range of cancerogenesis, after previous initiation. In the future, enhanced chances may be foreseen for active prevention and for causal elucidation of cancer formation, which until now seems to be a spontaneous disease.
    Notizen: Zusammenfassung An Hand eines Tagungsberichtes (Annual Symposium on Fundamental Cancer Research, Houston, und Internationaler Ernährungskongreß, San Diego) wird vor allem auf Fragen der Kanzerogenese eingegangen: Rolle von Carotinoiden als Hemmstoffe und Rolle von Pyrolyse-Produkten als Förderer der Krebsentstehung, beide überwiegend im Bereich der Promotion nach anderweitig erfolgter Initiation. Hier liegen für die Zukunft Chancen aktiver Prävention und kausaler Aufklärung bisher scheinbar schicksalhafter (Spontan-)Erkrankungen.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 12-19 
    ISSN: 1436-6215
    Schlagwort(e): Energie ; Wärmeproduktion ; Realimentation ; Nüchternumsatz ; Erhaltungsumsatz
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary A metabolism trial with six adult sows was conducted to study the effect of fasting and realimentation on heat production, energy retention, and utilization of energy. Complete balance measurements by indirect calorimetry (CN-method, RQ-method) were carried out from the 8th to the 10th day of fasting, and thereafter from the 1st to the 7th day and from the 33rd to the 36th day of the realimentation phase. Previous to fasting and during the time of refeeding the energy supply was adapted to maintenance requirement. Heat production rose by 20% after refeeding the animals. This heat increment corresponded to 2.2 MJ/kg feed dry matter, or 12% of the energy intake, respectively. The stimulation of heat production induced by refeeding occurred spontaneously within one day. After the first day of refeeding a plateau was reached, which in the course of the steady energy supply was still present even after the 5th week of realimentation. Residual effects of fasting in the mode of a compensatory heat production were not observed. Therefore, a constant utilization of efficiency of metabolizable energy for maintenance was estimanted at 82%. The change of body energy during the entire experimental period resulted in a loss of 198 MJ corresponding to about 5% of the body weight.
    Notizen: Zusammenfassung In einem Gesamtstoffwechselversuch mit 6 ausgewachsenen Sauen wurden Wärmeproduktion und Energieretention bei Nüchterung und nachfolgender kontrollierter Realimentation untersucht. Die quantitative Stoffwechselmessung mit Hilfe der indirekten Kalorimetrie (CN-Methode und RQ-Methode) fand am 8.–10. Hungertag und am 1.–7. sowie 33.–36. Tag der Wiederfütterung statt. Die Nahrungszufuhr war vor und nach der Hungerphase auf den energetischen Erhaltungsbedarf ausgerichtet. Die Wärmeproduktion lag in der Realimentation gegenüber der Hungerphase um 20% höher. Dieser Wärmezuwachs entsprach 2,2 MJ/kg Futtertrockenmasse bzw. 12% der Energieaufnahme. Der Energiewechsel adaptierte sich innerhalb eines Tages an die Situation der Wiederfütterung. Danach blieb die Wärmebildung bzw. die Energieretention bis Ende des Versuchs auf einem konstanten Niveau. Nachwirkungen der Nüchterung im Sinne einer kompensatorisch veränderten Wärmeproduktion traten nicht auf. Die energetische Verwertung der umsetzbaren Energie für Erhaltung berechnete sich auf 82%. Die über die gesamte Versuchszeit erstellte Energiebilanz ergab ein Defizit der Körperenergie von 198 MJ, entsprechend etwa 5% des Körpergewichtes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 31-40 
    ISSN: 1436-6215
    Schlagwort(e): endogener Kotstickstoff ; bakterieller Stickstoff ; Guarmehl ; 15N-Tracer-Technik ; Ratten
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary The metabolic fecal nitrogen was determined in 8 young rats (90–100 g body weight) using a single oral dose of 75 mg15N-glycine. Four rats were fed a diet containing 8 % guar and 4 rats received a control diet without guar. Compared to the control group, apparent protein digestibility and nitrogen balance were significantly lower in the guar group. After an initial steep rise the15N-elimination in feces and urine (days 2–8 after15N-glycine application) followed an exponential curve in at least 2 phases, with increasing half-time values. The proportion of metabolic fecal nitrogen to total fecal nitrogen was calculated from the15N-atom-% excess, determined daily in urine and in feces. This calculation is based on the assumption that the specific15N-activity (15N-atom-% excess) in urine represents the specific15N-activity of the endogenous nitrogen pool. The addition of guar raised the proportion of metabolic fecal nitrogen from 51 % (control) to 73 %, corresponding to an increase in total fecal nitrogen loss (24 mg) observed in the guar-fed animals. This indicates that the rise in fecal nitrogen loss caused by guar is due almost entirely to enhanced secretion of endogenous nitrogen and not to undigested food protein. Based on the analysis of 2,6-diamino-pimelic acid in the feces of 4 rats the proportion of bacterial nitrogen in the feces was calculated. It amounted to 19.8 % of total fecal N in the control group, and to 30.1 % in the guar group, or to 39.4 % and 44.4 % of metabolic fecal nitrogen respectively. Obviously the increased dietary fiber intake also caused a rise in the amount of metabolic fecal nitrogen, which is derived from gastro-intestinal secretions and epithelial tissue.
    Notizen: Zusammenfassung Zur Bestimmung der endogenen Stickstoffausscheidung im Kot wurde acht jungen Ratten (90 bis 100 g Körpergewicht) eine orale Dosis von 75 mg15N-Glycin verabreicht. Vier Ratten erhielten eine 8%ige Guarmehldiät und vier Ratten eine Kontrolldiät ohne Guarmehlzusatz. Gegenüber der Kontrollgruppe wurde eine signifikante Verringerung der scheinbaren Proteinverdaulichkeit und der N-Bilanz in der Guarmehlgruppe festgestellt. Nach einem anfänglichen steilen Anstieg verlief die15N-Elimination in Kot und Urin vom 2. bis 8. Tag nach der15N-Glycin-Applikation exponentiell in mindestens zwei Phasen mit steigender Halbwertszeit. Aus den experimentell ermittelten Tageswerten des15N-Atom-%-Überschusses in Urin und Kot wurde der Anteil des endogenen Stickstoffs im gesamten Kotstickstoff berechnet. Hierbei wurde vorausgesetzt, daß die spezifische15N-Aktivität des Urins (15N-Atom-%-Überschuß) dem15N-Markierungsgrad des endogenen Stickstoff-Pools entspricht. Durch Guarmehlzusatz erhöhte sich der Anteil des endogenen Kotstickstoffs von 51% (Kontrollgruppe) auf 73%, was einem Anstieg von 10 mg N/Tag auf 32 mg N/Tag entspricht. Diese Differenz von 22 mg N/Tag ist vergleichbar mit dem um 24 mg/Tag erhöhten N-Verlust im Kot der Tiere in der Guarmehlgruppe. Demnach sind die durch Guarmehl verursachten erhöhten N-Verluste fast ausschließlich durch eine vermehrte endogene N-Sekretion und nicht durch unverdautes Nahrungsprotein bedingt. Mit Hilfe der 2,6-Diamino-pimelinsäure-Analyse des Kots von vier Ratten wurde der Anteil des aus Darmbakterien stammenden Kot-N bestimmt. Er betrug 19,8 % (Kontrollgruppe) bzw. 30,1% (Guarmehlgruppe) des Gesamt-Kot-N bzw. 39,4% (Kontrollgruppe) und 44,4 % (Guarmehlgruppe) des endogenen Kot-N. Hieraus ist zu folgern, daß die erhöhte Ballaststoffzufuhr auch eine vermehrte Ausscheidung an endogenem Stickstoff in Form von N-haltigen Sekreten und Epithelzellen des Magen-Darm-Traktes bewirkt hat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 58-65 
    ISSN: 1436-6215
    Schlagwort(e): Feststoffsubstrate ; Kolonienbildung von Mikroorganismen
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Bacteria have been found to grow differently at contact sites to both organic and anorganic solids as on pure agar media. Of 16 ad hoc selected bacterial strains, the following species (arranged in decreasing order) responded with stronger colony formation: Bacillus subtilis, B. cereus, Streptococcus sanguis, S. saprophyticus, S. faecalis, Escherichia coli, Micrococcus flavus, Actinomyces viscosus, Veillonella sp., Enterobacter liquefaciens, Yersinia enterocolitica. Lactobacillus casei behaved neutral. Proteus vulgaris, Y. enterocolitica and Chromobacterium violaceum grow on certain media only in the presence of solid particles. The yeasts Endomyces lactis, Saccharomyces cerevisiae, Rhodotorula mucilaginosa and Cryptococcus nigricans did not respond to solid particles during colony formation. The kind of protein — animal (meat) or vegetable (soy beans) — did not influence the behaviour of the microorganisms in these experiments.
    Notizen: Zusammenfassung Es wurde festgestellt, daß die Bakterien an Kontaktstellen mit sowohl organischen als auch anorganischen Feststoffmaterialien anders wachsen als auf reinen Agarnährböden. Von 16 ad hoc gewählten Bakterienstämmen reagierten folgende Spezies mit intensiverer Kolonienbildung in sinkender Reihenfolge: Bacillus subtilis, B. cereus, Streptococcus sanguis, S. saprophyticus, S. faecalis, Escherichia coli, Micrococcus flavus, Actinomyces viscosus, Veillonella sp., Enterobacter liquefaciens, Yersinia enterocolitica. Lactobacillus casei verhielt sich neutral. Proteus vulgaris, Y. enterocolitica und Chromobacterium violaceum wachsen auf bestimmten Nährböden nur in Anwesenheit der Festpartikel. Die Hefen Endomyces lactis, Saccharomyces cerevisiae, Rhodotorula mucilaginosa und Cryptococcus nigricans zeigten bei der Kolonienbildung keine Reaktion auf die Feststoffpartikel. Die Art des Proteins in Nährböden — tierisch (Fleisch) oder pflanzlich (Sojabohnen) — beeinflußte das Verhalten der Mikroorganismen in diesen Untersuchungen nicht.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 11
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 104-112 
    ISSN: 1436-6215
    Schlagwort(e): vitamin A ; inner ear ; review ; vitamin A deficiency ; hearing loss
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Since the first characterization and description of vitamin A this is used in otolaryngologic therapy for different forms of hearing disorders, and its relation to the inner ear is subject of investigation. Animal experiments and clinical studies were done to clarify the significance of vitamin A for the function of hearing. Besides this there were a lot of observations describing correlations between vitamin A metabolism and hearing loss. Recent investigations showed that vitamin A is present in high concentrations in the inner ear and stored there. Morphological experiments revealed different and in some way contradictory results, but they showed that vitamin A seems to be essential for inner-ear morphogenesis.
    Notizen: Zusammenfassung Seit der Entdeckung des Vitamin A und ersten Beschreibung seiner Wirkung wird dieses auch in der Otorhinolaryngologie als Therapeutikum bei den unterschiedlichsten Formen von Hörstörungen eingesetzt und seine Wirkungsweise am Innenohr erforscht. So wurden sowohl tierexperimentelle als auch klinische Studien durchgeführt, um die Bedeutung des Vitamins für die Funktion des Hörorgans zu klären. Daneben wurden eine Reihe von Beobachtungen mitgeteilt, die einen Zusammenhang zwischen Störungen des Vitamin-A-Stoffwechsels und gleichzeitig auftretenden Hörstörungen beschrieben. Neuere Untersuchungen haben ergeben, daß Vitamin A in hohen Konzentrationen im Innenohr vorkommt und dort auch gespeichert werden kann. Morphologische Untersuchungen führten zu den unterschiedlichsten Ergebnissen und haben gezeigt, daß Vitamin A für die Morphogenese des Innenohres von Bedeutung zu sein scheint.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 276-282 
    ISSN: 1436-6215
    Schlagwort(e): starvation ; brain ; lipid metabolism ; dietary lipids
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Einfluß verschiedener Nahrungsfette auf den Lipidstoffwechsel des Gehirns während Hunger wurde untersucht. Albinoratten wurden 8 Tage lang mit Dalda, Senföl oder Erdnußöl gefüttert. Einige Tiere blieben anschließend 3 und 5 Tage lang ohne Nahrung. Die Gesamtlipide und die Galaktolipide wurden durch Nahrungsfette und durch Hunger nicht beeinflußt, während die Phospholipide unabhängig von der Art des Nahrungsfetts signifikant zunahmen. Cholesterin nahm in den mit Dalda und mit Erdnußöl gefütterten Gruppen zu und nahm ab während des Hungerns. In der Hungerperiode im Anschluß an die Fettzufuhr war der Einbau von 1-14C-Acetat in Lipide von Gehirnschnitten nach Erdnußöl höher als nach Dalda. Nach Senföl war der Einbau nur gering.
    Notizen: Summary In this study the effects of the dietary fat sources, viz., Dalda, mustard oil and groundnut oil in the brain lipid metabolism during starvation has been investigated. To find out this, these oils were fed to albino rats for 8 weeks followed by 3 and 5 days of starvation. Total as well as galactolipids of brain were not affected by dietary oils and starvation, whereas phospholipids of brain were significantly increased by fasting irrespective of the dietary fats. On the other hand, cholesterol was found to be increased in the groups fed with Dalda and groundnut oil and to be significantly decreased during fasting experiments. Incorporation of (1-14C)acetate into lipid of the brain slices of rats fed different experimental diets than followed by starvation revealed that the uptake of radioactivity was higher in the group fed with groundnut oil, followed by Dalda. Low uptake was observed in the group fed with mustard oil.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 133-142 
    ISSN: 1436-6215
    Schlagwort(e): Key words Flavonoids – cancer-cell lines – proliferation –, cytotoxicity – apoptosis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Their proposed protective role in tumor development may prevail especially in the intestinal tract due to direct exposure of intestinal epithelia to these dietary ingredients. We have screened more than 30 flavonoids for their effects on cell proliferation and potential cytotoxicity in the human colon cancer cell lines Caco-2, displaying features of small intestinal epithelial cells, and HT-29, resembling colonic crypt cells. In addition, for selected compounds we assessed whether they induce apoptosis by determining caspase-3 activation. Studies on the dose dependent effects of the flavonoids showed antiproliferative activity of all compounds with EC50 values ranging between 39.7 ± 2.3 μM (baicalein) and 203.6 ± 15.5 μM (diosmin). In almost all cases, growth inhibition by the flavonoids occured in the absence of cytotoxicity. There was no obvious structure-activity relationship in the antiproliferative effects either on basis of the subclasses (i.e., isoflavones, flavones, flavonols, flavanones) or with respect to kind or position of substituents within a class. In a subset of experiments we examined the antiproliferative activities of the most potent compound of each flavonoid subgroup in addition in LLC-PK1, a renal tubular cell line, and the human breast cancer cell line MCF-7. Out of four flavonols tested, three displayed almost equal antiproliferative activities in all cell lines but fisetin was less potent in MCF-7 cells. The flavanones bavachinin and flavanone inhibited growth of Caco-2 and HT-29 cells with lower EC50 values than that obtained in LLC-PK1 and MCF-7 cells. The lower susceptibility of LLC-PK1 and MCF-7 cells towards growth arrest was even more pronounced in the case of the flavone baicalein. Half maximal growth-inhibition in LLC-PK1 and MCF-7 required 2.5 and 6.6 fold higher concentrations than that needed in the intestinal cell lines. The flavonoids failed to affect apoptosis in LLC-PK1 and MCF-7, whereas baicalein and myricetin were able to induce apoptosis in HT-29 and Caco-2 cells. In conclusion, flavonoids of the flavone, flavonol, flavanone, and isoflavone classes possess antiproliferative effects in different cancer cell lines. The capability of flavonoids for growth inhibition and induction of apoptosis can not be predicted on the basis of their chemical composition and structure.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 177-182 
    ISSN: 1436-6215
    Schlagwort(e): Key words Dietary fat – adipose tissue – lipolysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Abstract Variations in total energy intake and composition of daily food play an important role in the regulation of metabolic processes and so, in the control of body weight. This study was designed in order to investigate the effect of a high-fat diet on lipolysis in isolated adipocytes. For this purpose, fourteen Wistar rats were divided into two groups and fed either a standard-fat diet or a high-fat diet ad libitum for 7 weeks. Adipocytes were prepared from fat pads by collagenase digestion and incubated in vitro in the absence or presence of various lipolytic agents. Lipolysis was measured by the release of glycerol into the medium during 90 min of incubation. We observed that a high amount of fat in the diet induced an enlargement of adipose tissue, which was accompanied by a reduction of β-adrenergic agonist-induced lipolysis, that could be due to a loss of β1 and β3-adrenoceptor number or to alterations of their coupling to adenylate-cyclase through the guanine nucleotide regulatory protein. New data about regional differences were provided by comparing two adipose locations (subcutaneous and visceral).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    ISSN: 1436-6215
    Schlagwort(e): Key words Wine polyphenols – 8-hydroxy-2'-deoxyguanosine – oxidative damage – 2-nitropropane – 1,2-dimethylhydrazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Flavonoids are polyphenolic antioxidants occuring in vegetables and fruits as well as beverages such as tea and wine which have been thought to influence oxidative damage. Aim of the study: We wanted to verify whether a complex mixture of wine tannins (wine complex polyphenols and tannins, WCPT) prevent chemically-induced oxidative DNA damage in vivo. Methods: Oxidative DNA damage was evaluated by measuring the ratio of 8-hydroxy-2'-deoxyguanosine (80HdG)/ 2-deoxyguanosine (2dG) × 10−6 in hydrolyzed DNA using HPLC coupled with electrochemical and UV detectors. Results: We treated rats with WCPT (57 mg/kg p.o.) for 14 d, a dose 10-fold higher than what a moderate wine drinker would be exposed to. WCPT administration significantly reduced the ratio of 80HdG/2dG × 10−6 in liver DNA obtained from rats treated with 2-nitropropane (2NP) relative to controls administered 2NP only (33.3 ± 2.5 vs. 44.9 ± 3.2 × 10−6 2dG; μ± SE; p〈0.05). On the contrary, pretreatment with WCPT for 10 d did not protect the colon mucosa from oxidative DNA damage induced by 1,2-dimethylhydrazine (DMH). 2NP and DMH are hepatic and colon carcinogens, respectively, capable of inducing oxidative DNA damage. Conclusions: WCPT have protective action against some types of chemically-induced oxidative DNA damage in vivo.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 16
    ISSN: 1436-6215
    Schlagwort(e): Key words Anthocyanidins – anthocyanins – comet assay – antioxidative potential – oxidized DNA-bases
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Anthocyanins are common colored plant flavonoids, occurring as glycosides of the respective anthocyanidin-chromophores. Like other flavonoids, anthocyanidins are also expected to have antioxidative and antimutagenic properties in vivo, although only few data are available. To gain more knowledge on possible protective mechanisms in mammalian cells, we have compared their extracellular and intracellular antioxidative potential in vitro and in human colon tumor cells. We used Aronia melanocarpa Elliot anthocyanin (AA) concentrates, fractions thereof, concentrates from Elderberry, Macqui, and Tintorera fruits, as well as pure compounds. In vitro, antioxidative properties of the samples were studied with the ferric reducing ability assay (FRA assay). As a measure of intracellular oxidative/antioxidative effects, H2O2-induced strand breaks as well as oxidized DNA bases were determined in human tumor HT29 clone 19A cells using a microgelelectrophoresis assay (comet test). Major results were that isolated compounds (aglycons and glycosides) and complex plant samples are powerful antioxidants in vitro. In fact their activities by far exceeded those of Trolox and vitamin C in the FRA assay. Also H2O2-induced DNA strand breaks were reduced in cells treated with the complex plant extracts. In contrast, endogenous generation of oxidized DNA bases was not prevented. In summary, the intracellular steady state of oxidized DNA bases is not altered by anthocyanins or anthocyanidins. This findings raises questions with respect to the cancer preventive potential of anthocyanidins within specific tissues, such as the colon. Extracellularly, however, the compounds are potent antioxidants. This points to their potential for providing systemic protection in vivo, e.g., by scavenging oxidants in the blood stream and in the colon. Notably, both aglycons and glycosides have equally strong antioxidant activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    ISSN: 1436-6215
    Schlagwort(e): Key words Estrone – estrogen – obesity – dietary estrogen
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background Estrone is a relatively abundant hormone widely distributed in tissues of animal and plant origin. It is a mild estrogen that induces increases in body weigt in experimental animals. The relative abundance of estrone esters in animal tissues suggests that it may also be found in foods, from which it may alter the mechanisms of body weight control. Aim of the study To measure the total estrone content in food and to determine whether this may affect body weight. Methods In the first part of the study, a method was devised for the measurement of total estrone content in food. This was applied to the analysis of estrone content in a variety of food. Finally, hyperlipidic diets (18.6 MJ/kg) with a total estrone content 0.89 ± 0.21 μmol/kg (control group) and 1.37 ± 0.13 μmol/kg (laced with estrone fatty esters) were given to rats during 15 days, in order to determine the influence of dietary estrone on the body mass. Zucker lean (Fa/?) rats weighting initially 200–215 g were used. The total estrone (essentially as fatty esters) content of food was investigated by combining a dried methanol extraction with saponification and measurement of the free estrone evolved through radioimmunoassay. Result The content of estrone was zero in some vegetables, but significant in fruits, meats, and especially fats, both of plant and animal origin. The application of these analyses to a standard recommended diet for humans may result in intakes of more than 1 μmol of estrone per day, a figure comparable to the estrogen production by women. When rats were exposed to a raised estrone content in a fat-rich diet, they significantly increased their body weights, doubling their rate off growth (1.99 g/day) compared with controls (0.81 g/day), but maintaining their plasma composition and the proportions of lipid, water, and protein in their carcasses. Conclusion The widely distributed estrone esters in food and their relatively high concentrations may result in high free hormone intakes in humans. The continued and massive intake of estrone may enhance tissue deposition and lead to obesity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 18
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 295-296 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 286-292 
    ISSN: 1436-6215
    Schlagwort(e): Key words Plant oils – tocopherols – sister chromatid exchanges
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Plant fats and oils are major sources of mono- and polyunsaturated fatty acids as well as vitamin E, the major fat-soluble antioxidants in human nutrition. Dietary antioxidants are expected to reduce cancer risk by minimizing DNA damage. Aim of the study: To compare the effects of γ-tocopherol rich corn oil and the mixture of the α-tocopherol rich olive/sunflower oil on plasma concentration of tocopherols and on the frequency of sister chromatid exchange (SCE), an indicator of DNA damage. Methods: This study had a double-blind, cross-over design and was conducted in 20 normal healthy non-smoking males aged 19–31 years. Design included a 2-week adjustment period and two 2-week test periods in which diets containing 30% energy as fat including either 80 g of corn oil (CO) (20 mg α-tocopherol, 100 mg γtocopherol) or 80 g of olive/sunflower oil (OSO) (24 mg α-tocopherol, 2.4 mg γ-tocopherol) as the main fat-source, were given. Blood samples for analysis of SCE rate and content of tocopherols were collected at the beginning (T0), after adjustment (T1) and after the test period (T2) in intervals of 2 weeks. Results: After two weeks of the corn oil diet, the plasma concentration of γ-tocopherol increased but α-tocopherol decreased significantly compared to the olive/sunflower oil diet. The concentration of α-tocopherol increased (CO: 22.99 ± 1.11 vs. OSO: 24.40 ± 1.49 μmol/l) and that of γ-tocopherol decreased (CO: 4.19 ± 0.29 vs. OSO: 2.99 ± 0.25 μmol/l) after the olive/sunflower oil diet. Intake of the corn oil diet was associated with reduced SCE rate and intensity, whereas there was no change in SCE after the olive/sunflower oil diet (CO: 7.66 ± 0.25 vs. OSO: 8.06 ± 0.47 mean SCE/cell). Conclusions: The combination of γ-tocopherol with α-tocopherol in corn oil diet despite the lower α-tocopherol equivalents/diene acid equivalents ratio achieved better protection against DNA damage than α-tocopherol alone in the olive/sunflower oil diet.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 1-43 
    ISSN: 1436-6215
    Schlagwort(e): arteriosclerogenesis ; capillary basement membrane thickening ; heart infarction ; protein storage ; risk factor diseases
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 21
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 69-75 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Oxal-, Glyoxyl- und GlykollsÄure wurden in Rattenleber und -niere nach Injektion von [U-14C]-Xylit oder [U-14C]-Glucose bestimmt. Weder Glucose noch Xylit führten zu einer Oxal- oder GlyoxylsÄurebildung. GlycollsÄure wurde jedoch in beiden Geweben nach Injektion von Xylit gefunden. Mögliche Stoffwechselwege vom Xylit zur GlykollsÄure werden diskutiert.
    Notizen: Summary Oxalic, glyoxylic, and glycollic acid were determined in rat liver and kidney after injection with [U-14C]-xylitol or [U-14C]-glucose. Neither glucose nor xylitol led to the formation of oxalic and glyoxylic acid, yet glycollic acid was found in both tissues after injection with xylitol. Possible pathways leading from xylitol to glycollic acid are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 55-68 
    ISSN: 1436-6215
    Schlagwort(e): Sojaprotein ; Radioimmunoassay (Radioimmuntest) ; Proteindenaturierung ; Passive HÄmagglutination (Sojamehl)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Soy-bean protein loses its immunogenicity by heat treatment through thermal denaturation. Incubation with 6m guanidine-hydrochloride restores the immunogenicity. This reagent causes dissociation of protein aggregates formed during autoclaving of soy protein. This seems to be the major step in the restitution of immunogenicity. These findings are discussed in connection with the quantification of heat-denaturated soy-bean protein by two independent immunologic methods: Solid-Phase Radioimmunoassay and Passive Hemagglutination (inhibition test).
    Notizen: Zusammenfassung Durch thermische Denaturierung geht die ImmunogenitÄt von Sojaprotein verloren. Inkubation mit 6m-Guanidin-HCl stellt die ImmunogenitÄt wieder her. Durch dieses Reagens wird die bei Autoklavieren beobachtete Assoziation eines Teils der Sojaproteine wieder rückgÄngig gemacht. Dies dürfte die Hauptursache für die Rückgewinnung der ImmunogenitÄt sein. Diese Befunde werden im Zusammenhang mit der Bestimmung von autoklaviertem Sojaprotein durch zwei immunologische Verfahren diskutiert: Solid-Phase Radioimmunoassay und passive HÄmagglutination (Inhibitionsverfahren).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 23
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 44-54 
    ISSN: 1436-6215
    Schlagwort(e): elapids ; viperids ; phosphomonoesterases
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Non-specific acid and alkaline phosphomonoesterases could be demonstrated in two viperids (Cerastes cerastes andCerastes vipera) and two elapids (Naja haje andNaja nigricollis). The latter could be a natural source for the production of these enzymes. The activities of both enzymes in elapids were greater than in viperids.N. nigricollis was the only to show acid phosphatase activity exceeding its alkaline one. The optimum pH values recorded for acid phosphatase was 4.0 and 4.9 and for alkaline phosphatase 9.0 and 10.0 in viperids and elapids, respectively. Optimum substrate concentration for both enzymes in viperids was 0.01 M, while for acid phosphatase inN. haje andN. nigricollis it was 0.125 and 0.150 M; and for their alkaline phosphatases the values were 0.150 and 0.125 M, respectively. Mg++ behaved as an activator for both enzymes in all venoms investigated, while Zn++ showed either no or slight activating effect. Fluoride ions as well as EDTA showed certain inhibitory action. Both enzymes in the crude venoms were heat-labile.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 76-80 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    ISSN: 1436-6215
    Schlagwort(e): germ-free rat ; intestinal tract colonization ; interaction ; protection ; Bifidobacterium ; E. coli
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Das Vorherrschen von Bifidobakterien in normalen, mit Muttermilch ernährten Säuglingen ist gut dokumentiert. Sogar unter ungünstigen hygienischen Bedingungen bei der Geburt und während der Stillperiode entwickeln sich die Bifidobakterien und kolonisieren den Darmtrakt in großer Anzahl. In dieser Studie untersuchten wir die Wechselwirkung zwischen Bifidusbacterium longum und einem pathogenen E.-coli-Stamm in der keimfreien Ratte. Die Proliferation der beiden Bakterienstämme wurde durch sequenzielle Probeentnahme verfolgt. Die licht-mikroskopische und elektronen-mikroskopische Untersuchung von ausgewählten Darmabschnitten zeigte geringgradige morphologische Veränderungen. Die Bifidobakterien schützen die Ratten vollständig gegen Mortalität durch nachfolgende Infektion durch E. coli. Wiederholte Verabreichung von Bifidobakterien verminderte darüber hinaus die E.-coli-Population und hielt diese auf einem niedrigen Niveau. Daher erscheint die keimfreie Ratte als ein angemessenes Modell zum Studium der Entwicklung und Wechselwirkung von beiden Bakterienstämmen. Die Sequenz der Inokulation ist dabei von großer Bedeutung.
    Notizen: Summary The predominance of Bifidobacteria in normal breast-fed babies is well established. Even under unfavourable hygienic conditions of delivery and during the breast-feeding period Bifidobacteria develop and colonize the intestinal tract at high concentrations. In the present study we investigated the interaction between Bifidobacterium longum and a pathogenic E. coli strain in the germ-free rat. Sequential counts of the two bacterial strains allowed their proliferation to be followed. Electron microscopic as well as light microscopic examinations of selected intestinal mucosa segments revealed minor morphological changes. Bifidobacterium completely protected the rats against mortality from a consecutive infection with E. coli. Repeated inoculation of Bifidobacteria even decreased and kept down the initial E. coli population. Thus it appears that the germ-free rat is an appropriate model to study the development and interaction of both bacterial species and that the sequence of inoculation is most important.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 74-74 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 75-75 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 143-150 
    ISSN: 1436-6215
    Schlagwort(e): rice starch ; cooking quality ; physicochemical properties ; storage
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung 12 verschiedene Sorten von Reis aus Indien wurden im Hinblick auf die Auswirkung einer Lagerung bei verschiedenen Umgebungsbedingungen für die Dauer von 180 Tagen auf physikalisch-chemische Eigenschaften des Stärkeanteils und auf die notwendigen Garzeiten sowie die beim Garen eintretenden Verluste an Trokkensubstanz bzw. die Wasseraufnahme untersucht. Die Viskosität der Stärke nahm bei allen Reissorten während der Lagerung zu. Bezüglich der Garungszeiten waren keine größeren Unterschiede zwischen den Sorten zu beobachten, während die Wasseraufnahmen sehr unterschiedlich sein konnten.
    Notizen: Summary Twelve different varieties of rice including two flavorful varieties grown in the State of Maharashtra (India) have been studied with respect to the effect of storage, at ambient conditions, for 180 days on the physicochemical properties of the starch component as well as cooking quality.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 29
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 157-170 
    ISSN: 1436-6215
    Schlagwort(e): Dünndarmresorption ; Tumorstadium ; histologischer Typ ; Organlokalisation ; Ernährungstherapie
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary A deteriorating nutritional condition combined with the loss of body mass is one of the most noticeable symptoms of cancer. In order to answer the question to what extent absorption disorders in the small intestine are responsible for the malnutrition which develops, we studied 54 oncologic patients using modified D-xylose absorption tests. After the oral and intravenous administration of 10 g D-xylose at different times, the degree of absorption dependent on time was determined on the basis of a biophysical model. When accompanied by general nonspecific tumor symptoms, the frequency of absorption restrictions was increased. An established relation was found between the extent of small intestinal absorption, on the one hand, and the degree of spreading (staging) and the degree of histological differentiation of the carcinoma, on the other hand. Enteral absorption disorders represent a partial cause for the development of malnutrition in cancer patients and must be viewed as a result of a metabolic situation which is distinctly catabolic.
    Notizen: Zusammenfassung Die Verschlechterung des Ernährungszustandes und die Abnahme an Körpermasse ist eines der auffälligsten Symptome des Krebsleidens. Zur Beantwortung der Frage, inwieweit Störungen der Dünndarmresorption für die sich entwickelnde Malnutrition verantwortlich zu machen sind, untersuchten wir 54 onkologische Patienten mit Hilfe des modifizierten D-Xylose-Resorptionstests. Nach zeitlich getrennter oraler und intravenöser Applikation von 10 g D-Xylose wurde auf der Grundlage einer biophysikalischen Modellierung das Ausmaß der Resorption in Abhängigkeit von der Zeit ermittelt. Mit dem Auftreten allgemeiner unspezifischer Tumorsymptome erhöht sich die Häufigkeit von Resorptionseinschränkungen. Es konnte eine gesicherte Beziehung zwischen Ausbreitungsgrad (Staging), histologischem Differenzierungsgrad des Karzinoms einerseits und dem Ausmaß der Dünndarmresorption andererseits nachgewiesen werden. Enterale Resorptionsstörungen stellen eine Teilursache bei der Entwicklung einer Mangelernährung bei Krebskranken dar und sind selbst als Folge der katabol akzentuierten Stoffwechsellage anzusehen.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 30
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 219-229 
    ISSN: 1436-6215
    Schlagwort(e): Maillard-Produkte ; Protein-Qualität ; Wachstum und Nephrozytomegalie bei Ratten
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Two experiments lasting 10 vs. 8 weeks respectively were conducted in order to determine the effects of feeding heated proteins (casein + glucose, 65 °C for 4 days) on histopathological alterations in the kidneys of rats. Histological examinations showed enlarged epithelial cells and cell nuclei in the pars recta of the proximal tubules (inner stripe of the inner kidney cortex zone) beginning after two weeks of the test. The differences in the average size of the nuclei were significant after a feeding period of 6, 8 or 10 weeks (44 rats in the testgroup vs. 36 rats in the controlgroup respectively). In this way the alterations are very similar to that which are induced by lysinoalanine. The substance causing the lesions seems not to be fructoselysine although it was present in the heat damaged diets in concentrations of 16,000–23,000 ppm but is suggested among the substances formed in the early and advanced stage of Maillard reaction.
    Notizen: Zusammenfassung In zwei Versuchen von 10 bzw. 8 Wochen Dauer wurde der Einfluß der Fütterung eines hitzegeschädigten, lysinoalaninfreien Proteins (Casein+Glucose, 65 °C, 4 Tage) auf histopathologische Veränderungen in Rattennieren untersucht. In den histopathologischen Präparaten der Nieren waren schon nach zwei Wochen vergrößerte Tubulusepithelzellen in der pars recta des proximalen Tubulus zu erkennen. Zellkernmessungen in der 6., 8. und 10. Versuchswoche ergaben eine signifikante Erhöhung der mittleren Zellkerngröße bei den Versuchstieren (n=44) im Vergleich zu den Kontrolltieren (n=36). Damit waren die Veränderungen vergleichbar mit den aus der Literatur bekannten, durch Lysinoalanin induzierten histopathologischen Befunden. Das auslösende Agens für die Nephrocytomegalie konnte nicht identifiziert werden. Es dürfte im Bereich der vielen Zwischenprodukte aus dem Initial- und Zwischenstadium der Maillard-Reaktion zu suchen sein.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 31
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 113-125 
    ISSN: 1436-6215
    Schlagwort(e): Muttermilch ; Triglyceride ; Cholesterin ; Phospholipide ; Fettsäuren
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary The dependency of the human milk lipids triglycerides (TG), cholesterol (Chol), phospholipids (PL), and the fatty acid composition of both TG and PL on the stage of lactation, the day time, the course of one nursing, and on the mother's diet was shown by analyzing more than 350 milk samples. In progressing lactation (day 1–36) TG increased from 1.9 to 3.9 g/100 ml. Chol decreased from 35 to 20 mg/100 ml, while PL remained with 40 mg/100 ml rather constant. The resulting decrease in the PL/TG- and Chol/TG-ratios indicates an increasing size of fat globules. During one nursing, TG and Chol increased four-fold and PL doubled. During the day lipids (TG, Chol, PL) of the milks of German mothers reached their peak values in the afternoon, whereas the ones of milks obtained from English mothers were found in the late evening. With 3 mothers (n=3) carbohydrate-rich diets (65 cal%) led to an increase of the milk fat content. In contrast high fat diets (50 cal%) resulted in milks with low fat contents (2.6/4.1 g/100 ml). Chol (20.8/37.5 mg/100 ml) and PL (26.4/ 45.3 mg/100 ml) showed the same dependency. The fatty acid composition changed mainly dependent on the duration of the lactation and the mother's diet, but not during one single nursing and during the day. Long-chain polyunsaturated fatty acids were higher in early than in mature milks. The P/S-ratio of TG was found to remain constant in progressing lactation (0.32), whereas the one of PL increased from 0.6 to 0.71. Dependent on the regimen of the mother the P/S-ratios (n=3) were found to be 0.27 (high carbohydrate diet) and 0.46 (high fat/high linoleic acid diet).
    Notizen: Zusammenfassung Mit der Analyse von über 350 Frauenmilchproben konnte die Abhängigkeit der Frauenmilchlipide — Triglyceride (TG), Cholesterin (Chol), Phospholipide (PL), Fettsäurezusammensetzung der TG und PL — vom Stadium der Laktation, der Tageszeit, dem Verlauf des Stillvorgangs und der mütterlichen Ernährung gezeigt werden. Im Verlauf der Laktation (1.–36. Tag) nahm der TG-Gehalt der untersuchten Proben von 1,9 auf 3,9 g/100 ml zu. Chol sank von 35 auf 20 mg/100 ml. Der PL-Gehalt blieb mit 40 mg/100 ml weitgehend konstant. Die sich aus den Ergebnissen ableitenden Chol/TG- und PL/TG-Quotienten deuten auf eine Zunahme der Fettkügelchengröße im Laufe der Laktation hin. Während eines Stillvorganges stiegen die TG und Chol um das nahezu Vierfache an, wogegen sich der PL-Gehalt nur verdoppelte. Über den Tag gesehen hatten Milchen deutscher Mütter ihre höchsten Lipidwerte (TG, Chol, PL) am Nachmittag, wogegen die Maxima der englischen Milchproben am späten Abend gefunden wurden. Kohlenhydratreiche Ernährungsweise (65 cal%) führte bei Müttern (n=3) zu einem Anstieg des Milchfettgehalts, wogegen umgekehrt aus fettreicher Ernährung relativ fettarme Milchen resultierten (2,6/4,1 g/100 ml). Entsprechend verhielten sich Chol (20,8/37,5 mg/ 100 ml) und die PL (26,4/45,3 mg/100 ml). Die Fettsäurezusammensetzung änderte sich vor allem in Abhängigkeit von der Laktation und der mütterlichen Ernährung, nicht aber während des Stillvorganges und im tageszeitlichen Verlauf. Frühe Milch ist besonders reich an langkettig polyungesättigten Fettsäuren. Der P/S-Quotient der TG blieb im Verlauf der Laktation mit 0,32 weitgehend konstant, wogegen derjenige der PL von 0,6 auf 0,71 anstieg. Je nach Ernährungsweise der Mutter lag der P/S-Quotient (n=3) bei 0,27 (kohlenhydratreich) und bei 0,46 (fettreich, linolsäurereich).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 32
    ISSN: 1436-6215
    Schlagwort(e): tierexperimenteller Thiaminmangel ; Pyruvatverwertungsstörung ; Laktazidose ; Aminosäurehomöostasestörung
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary The metabolic effects of thiamine deficiency on the metabolism of lactate, acid-base and amino acids were evaluated both with and without muscular exercise in a controlled animal experiment. Thiamine deficiency — in good correlation with its biologic halftime and also with reports in the literature — caused with a latency of 17–56 days and statistically proven in parallel the following effects: 1. hyperlactemia 2. in comparison to controls elevated plasma concentrations of threonine, alanine, glutamic acid, glutamine, histidine, methionine, taurine, valine, isoleucine and leucine 3. distinctly lowered — also in comparison to controls — plasma concentrations of arginine and tryptophan. Furthermore, in the thiamine deficient rats predetermined muscular exercise caused the following effects, also occurring concomitantly: 1. life threatening lactacidosis 2. marked — statistically prover — disturbance of the homeostasis of alanine, glycine, methionine and arginine 3. distinctly — and statistically significant — elevated plasma concentration of proline 4. statistically significantly lowered plasma concentrations of taurine. The reasons for all these changes under thiamine deficiency is most likely a metabolic one primarily due to a disturbance of the utilization of pyruvate in the liver. An additional disturbance of both the transsulfuration pathway and the Krebs-Henseleit-cycle seems probable. The physiologic regulation of pyruvate, lactate, alanine, serine and tyrosine during muscular exercise in correlation to the controls is being discussed.
    Notizen: Zusammenfassung In einer kontrollierten tierexperimentellen Studie werden die metabolischen Wirkungen eines definierten Thiaminmangels auf den Lactat-, Säuren-Basen- und Aminosäurenhaushalt unter Ruhe- und Belastungsbedingungen überprüft. In guter Korrelation zur biologischen Halbwertszeit von Thiamin und in Übereinstimmung mit Literaturangaben bedingte die Thiaminmangelkost mit einer Latenz von 17 bis 56 Tagen parallel 1. statistisch gesicherte Hyperlaktatämien, 2. gegenüber den Kontrollwerten sehr deutlich, in der Mehrzahl statistisch gesichert erhöhte Plasmakonzentrationen von Threonin, Alanin, Glutaminsäure, Glutamin, Histidin, Methionin, Taurin, Valin, Isoleucin und Leucin sowie 3. gegenüber den Kontrollwerten sehr deutlich und statistisch gesichert erniedrigte Plasmakonzentrationen von Arginin und Tryptophan. Darüber hinaus bedingte die energetische Belastung im genormten Belastungstest bei den thiaminarm ernährten Tieren parallel bedrohliche Laktazidosen, erheblich, statistisch gesichert ausgeprägtere Homöostasestörungen von Alanin, Glycin, Methionin und Arginin, sehr deutlich und statistisch signifikant erhöhte Plasmakonzentrationen von Prolin sowie statistisch signifikant abgesunkene, wieder im Bereich der Kontrollwerte liegende Plasmakonzentrationen von Taurin. Für die Mehrzahl der unter Thiaminmangel erhobenen Befunde muß als entscheidende metabolische Ursache eine hepatische Verwertungsstörung von Pyruvat angenommen werden. Störungen des Transsulfuration-Pathway und Krebs-Henseleit-Zyklus erscheinen wahrscheinlich. Die physiologische Regulation von Pyruvat, Lactat, Alanin, Serin und Tyrosin bei muskulärer Arbeit wird anhand der Kontrollwerte diskutiert.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 33
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 230-236 
    ISSN: 1436-6215
    Schlagwort(e): selenium ; vegetable ; fruit ; cereals ; infant food
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Selengehalt der Nahrung weist große regionale Unterschiede auf. Nahrungsproben von Säuglings- und Kleinkinderkost aus Nordrhein-Westfalen wurden mit Hilfe der instrumentellen Neutronenaktivierungsanalyse untersucht und zeigten, daß der Selengehalt der hiesigen Gemüse und Früchte durchschnittlich etwa 5 ng/g beträgt. Nur Proben von Kartoffeln und Bananen weisen einen höheren Selengehalt auf. Bananen, importiert aus verschiedenen Gebieten der Erde, zeigen eine extrem hohe Schwankungsbreite mit Werten zwischen 4 und 164 ng Se/g. Fertiggerichte für Säuglinge und Kleinkinder haben einen der Kuhmilch vergleichbar niedrigen Selengehalt von durchschnittlich 24 ng/g. Außer Eiern enthalten nur Milchbreie und einige andere getreidehaltige Produkte mehr als 100 ng Se/g.
    Notizen: Summary The selenium content of food exhibits great regional differences. Food samples of infants and young children from the North Rhine-Westphalia State in the Fed. Rep. of Germany were analysed by instrumental neutron activation analysis and showed that the average selenium content of local vegetable and fruit is below 5 ng/g wet weight. Only samples of potatoes and bananas exhibit higher selenium contents. The bananas, probably imported from different areas of the world, show an extremely high variance with values between 4 and 164 ng Se/g. Commercially available ready-for-use meals for infants or young children have a low Se content (median 24 ng/g) which is comparable to cow's milk. Besides eggs, cereals enriched with milk and some other cereal products contain more than 100 ng Se/g.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 1-13 
    ISSN: 1436-6215
    Schlagwort(e): Key words Pharmacotherapy – obesity – appetite suppressant – thermogenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Many new substances are currently being investigated for their usefulness in the pharmacotherapy of obesity. Most drugs interfere with monoamine neurotransmitter (serotonin, noradrenalin, dopamine and histamine) effects and act as an appetite suppressant. Other approaches are to primarily increase thermogenesis (e.g. β3-adrenoceptor agonists), or to decrease fat absorption by inhibiting the pancreatic lipase (orlistat). New promising agents are substances that increase the effect of corticotropin releasing factor (CRF) or urocortin in the brain (CRF-binding protein ligand inhibitor) and a neuropeptide Y (NPY) Y5 receptor antagonist. The clinical relevance of leptin in the therapy of obesity is probably limited, but can not be fully evaluated at the moment. As obesity has a multifactorial basis, all these substances have in common the fact that they can not cure obesity. They should only be used as an adjunct to classical strategies like diet and exercise in severe obesity. For developing new, perhaps even more specific pharmacological agents, further research is needed to understand the individually different genetic and physiological basis of obesity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 35
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 35-44 
    ISSN: 1436-6215
    Schlagwort(e): Key words Carotenoids – lycopene – lutein –α-carotene –β-carotene – oxidation – antioxidant – human
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Aim of the study: The present study was conducted to investigate changes in the plasma concentration of carotenoids and carotenoid oxidation products, vitamin A, α- and γ-tocopherol, and ubiquinone-10 during a dietary intervention trial with 23 male healthy volunteers. Method: A two week carotenoid depletion period was followed by a daily consumption of 330 mL tomato juice (40 mg lycopene), then by 330 mL carrot juice (15.7 mg α-carotene and 22.3 mg β-carotene), and then by a 10 g spinach powder preparation (11.3 mg lutein and 3.1 mg β-carotene) served with main meals for two weeks, respectively. Blood samples were collected in the morning after an overnight fasting and carotenoids, vitamin A, tocopherols, and ubichinone were analyzed by reversed-phase HPLC. Results: During the tomato juice intervention, plasma concentrations of trans- and cis-lycopene increased 2-fold compared to the depletion period. Lycopene oxidation products could be demonstrated in plasma and were significantly elevated compared to control (p〈0.001). After two weeks of carrot juice consumption, α-carotene and β-carotene concentrations increased 8.6- and 3.2-fold, respectively. Finally, during the spinach consumption period the lutein concentration increased 2-fold, while the β-carotene concentrations were still elevated 2-fold. Conclusions: The moderate change in dietary habits, e.g., the consumption of 330 mL of carotenoid-rich vegetable juices caused significant changes in the plasma carotenoid concentrations, indicating a high bioavailability of carotenoids from the processed vegetable products. The changes in plasma carotenoid concentrations reflected the carotenoid composition of the consumed foods. However, particularly during the tomato juice intervention period the occurrence of lycopene oxidation products and cis-lycopene isomers in plasma was eminent. The formation may be due to antioxidant reactions of lycopene in the organism.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 51-75 
    ISSN: 1436-6215
    Schlagwort(e): Key words Iron – bioavailability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary In this review a broad overview of historical and current methods for the assessment of iron bioavailability was given. These methods can be divided into iron solubility studies, iron absorption studies, endpoint measures, and arithmetic models. The pros and cons of all methods were discussed. First, studies on in vitro and in vivo iron solubility have been described. The disadvantages of iron solubility include the impossibility of measuring absorption or incorporation of iron. Furthermore, only the solubility of nonheme iron, and not heme iron, can be studied. Second, we focused on iron absorption studies (either with the use of native iron, radioiron or stable iron isotopes), in which balance techniques, whole-body counting or postabsorption plasma iron measurements can be applied. In vitro determination of iron absorption using intestinal loops or cell lines, was also discussed in this part. As far as absorption studies using animals, duodenal loops, gut sacs or Caco-2 cells were concerned, the difficulty of extrapolating the results to the human situation seemed to be the major drawback. Chemical balance in man has been a good, but laborious and expensive, way to study iron absorption. Whole-body counting has the disadvantage of causing radiation exposure and it is based on a single meal. The measurement of plasma iron response did not seem to be of great value in determining nutritional iron bioavailability. The next part dealt with endpoint measures. According to the definition of iron bioavailability, these methods gave the best figure for it. In animals, the hemoglobin-repletion bioassay was most often used, whereas most studies in humans monitored the fate of radioisotopes or stable isotopes of iron in blood. Repletion bioassays using rats or other animals were of limited use because the accuracy of extrapolation to man is unknown. The use of the rat as a model for iron bioavailability seemed to be empirically based, and there were many reasons to consider the rat as an obsolete model in this respect. The double-isotope technique was probably the best predictor of iron bioavailability in humans. Disadvantages of this method are the single meal basis and the exposure to radiation (as far as radioisotopes were used). Finally, some arithmetic models were described. These models were based on data from iron bioavailability studies and could predict the bioavailability of iron from a meal.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 37
    ISSN: 1436-6215
    Schlagwort(e): Key words Obesity – oleoyl-estrone – leptin – Zucker fa/fa rat – white adipose tissue
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Oleoyl-estrone elicits powerful slimming effects on lean and obese rats, sparing protein, lowering appetite and maintaining energy expenditure. Leptin synthesis is markedly reduced by oleoyl-estrone. However, this effect is not observed in the obese Zucker fa/fa rats; these rats do not fully respond to leptin but they lose fat under oleoyl-estrone treatment. Aim of the study: To determine the role of leptin in the conversion of estrone to fatty-acyl estrone in white adipose tissue both in vivo in Zucker lean and obese rats, and in vitro. Methods: Two series of experiments were performed: a) Growth and differentiation of 3T3L1 preadipocytes into adipocytes followed by incubation with tritium-labeled estrone in the medium in the presence / absence of 1 nM leptin, and estimation of the incorporation of label into estrone and estrone ester fractions of cell extracts. b) Zucker lean (Fa/?) [ZL] and obese (fa/fa) [ZO] rats were injected i.v. with carrier-free oleoyl-estrone in chylomicra-sized liposomes, then euthanized after 10 min. Free and esterified estrone were measured in blood, liver, muscle, skin, white adipose tissue (WAT), and brown adipose tissue(BAT). Results: In the first study, in a 72-h incubation, adipocytes took up 20-27% of the medium estrone. In the leptin(−) controls, 47% of the label in the cell fraction was in the form of estrone esters and 45% as free estrone; in the leptin (+) cells, 71% of the label was in the estrone ester fraction and 24% was free estrone. In the second study, a large part of the injected tritium-label remained in the ZO blood, with only a small part remaining in ZL. In ZL 39% of the label was found in the tissues in the form of free estrone, and in ZO only 22%; in both cases about half of it was in WAT. Plasma free estrone levels were 0.3±0.1 nM in ZL and 0.5±0.3 nM in ZO, and esterified estrone was 242±99 nM for ZL and 201±29 nM for ZO. Plasma leptin levels were 1.73±0.16 ng/ml in ZL and 61.0±1.4 ng/ml in ZO. Conclusion: The presence of an intact leptin pathway is critical for the uptake and synthesis of estrone esters as well as for the plasma acyl-estrone turnover. The presented results show a direct relationship between oleoyl-estrone and leptin in the WAT. A fully functional leptin pathway is needed for the synthesis of acyl-estrone and the removal of free estrone from the bloodstream, as well as for the disposal of excess circulating oleoyl-estrone. This has a direct bearing on human and animal obesity, since estrone induces increases in fat deposition.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 38
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 143 
    ISSN: 1436-6215
    Schlagwort(e): Key words Phytoestrogen – cholesterol – DNA damage – comet assay – antioxidant
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Phytoestrogens are a major component of Asian diets and may be protective against certain hormone-dependent cancers (breast and prostate) and coronary heart disease. They may also have antioxidant function in scavenging potentially harmful free radicals and thus decreasing oxidative attack on DNA. Aims of the study: A pilot study to determine the effects of a phytoestrogen supplement, in the form of soy milk, on plasma LDL and HDL cholesterol levels and DNA damage in men. Methods: Ten healthy men participated in the study and were assigned to one of three groups consuming 1 litre of either soy milk, rice dream (vegetable protein control) or semi-skimmed cow's milk (animal protein control) each day for 4 weeks. Results: The soy supplement caused significant increases in plasma genistein and daidzein concentrations despite considerable interindividual variation (P〈0.001). Supplementation with soy resulted in a decrease in oxidative damage to DNA bases detected using the comet assay compared with controls (P〈0.05). However, there was no significant effect of the soy supplement on plasma cholesterol or triglyceride levels in comparison with control groups. Conclusions: A 4 week soy milk supplementation in healthy volunteers does not alter serum cholesterol levels but can have a protective effect against oxidative DNA damage in lymphocytes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 39
    ISSN: 1436-6215
    Schlagwort(e): Key words green tea – linoleic acid – antioxidants – lipid peroxidation – hemostasis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Green tea contains polyphenolic catechins which can act as antioxidants and thus decrease the risk for cardiovascular diseases. Aim of the study: To investigate whether green tea extract differs from placebo in its effects on markers of antioxidant status, lipid peroxidation, nitric oxide production, thromboxane production, and blood coagulation during a controlled high linoleic acid diet in healthy subjects. Methods: Twenty healthy non-smoking females (23–50 years) participated in a 4-week controlled intervention study. The experimental diet was rich in linoleic acid (9 en%) and contained fat, protein and carbohydrates: 27, 14, and 59 en%, respectively. In addition, the subjects ingested encapsulated green tea extract (3 g/d) or placebo mixture in a double-blind manner. Fasting blood samples and five 24-hour urines were collected before and at the end of the 4-week experimental period. Same samples were received from 10 control subjects. Results: Green tea extract significantly decreased plasma malondialdehyde (MDA) concentration in comparison with the placebo treatment. The treatments did not differ in serum lipids, indicators of antioxidant status, urinary 8-iso-prostaglandin F2α, 2,3-dinor-thromboxane B2, nitric oxide metabolites or coagulation indicators. Conclusions: We conclude that an amount of green tea extract which corresponds to 10 cups of tea per day for 4 weeks does not have specific effects on several indicators related to risk of cardiovascular diseases in comparison with placebo treatment. The relatively small but significant decrease in lipid peroxidation indicated by decreased plasma MDA was not associated with changes in markers of oxidative stress (urinary 8-iso-prostaglandin F2α and blood oxidized glutathione) or hemostasis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 40
    ISSN: 1436-6215
    Schlagwort(e): Key words Long chain polyunsaturated fatty acids – peroxidation – vitamin E – weanling rats
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Tissue 10:4(n-6) and 22:6(n-3) status have been correlated with neonatal development and growth. Artificial formulas for neonates have been supplemented with long chain polyunsaturated fatty acids (LCP) from animal and marine sources which may enhance sensitivity of cellular membranes to oxidative damage. Diet-derived antioxidants like vitamin E play a key role in the protection of tissue lipids against oxidation. Aim of the study: We seek to determine the influence of dietary vitamin E on tissue sensitivity to oxidative stress in rats fed for 4 weeks on diets enriched in (n-3) and (n-6) long-chain polyunsaturated fatty acids. Methods: Weanling rats received 10% fat diets that provided 18:1(n-9), 18:2(n-6) and 18:3(n-3) in a similar ratio to that of rat milk (group A), supplemented with fish oil (groups B and B+E) and supplemented with (n-6) and (n-3) LCP from an animal phospholipid concentrate (groups C and C+E). Vitamin E (500 mg vitamin E/kg fat) was added to diets B+E and C+E. Tissue fatty acid content and the activities of catalase, superoxide dismutase, glutathione transferase und glutathione peroxidase in liver and brain were measured. Glutathione status, vitamin E and the production of thiobarbituric acid reactive substances (TBARs) after incubation of erythrocyte, liver and brain lipids with inducers of enzymatic or non-enzymatic lipid peroxidation was measured. Results: Group B registered significantly lower total superoxide dismutase acitvity than group B+. Catalase activity was significantly higher in group C than in group C+E. Hepatic total and reduced glutathione levels were decreased in vitamin E supplemented groups compared to unsupplemented ones. TBARs production in erythrocyte lipids was significantly higher in groups B and C compared to vitamin E supplemented groups B+E and C+E. Conclusions: This study shows that the addition of vitamin E protected erythrocyte and liver microsome lipids enriched in (n-3) and (n-6) LCP from lipid peroxidation during the postnatal development of rats. The protection was more effectively in group C+E than in group B+E.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 41
    ISSN: 1436-6215
    Schlagwort(e): Key words Children – adolescents – nutrition counselling – dietary evaluation – scores
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary An intervention study by documented dietary counselling was carried out in a sample of 9 children and adolescents (12–,15 years) living in a full-time institution in Dortmund. Three weighed dietary records were collected over 3–7 days, one before and one after each of two individual nutrition counselling sessions, which were based on the recommended intake of food groups defined by the Optimized Mixed Diet (OMD), a quantitative preventive dietary conception for children and adolescents. As univariate dietary parameters (e.g., cholesterol intake), which are often used to show the effectiveness of nutrition counselling, do not take into account the multivariate complexitiy of nutrition, we developed 3 multivariate scores to measure the effectiveness of nutrition counselling. The are definded as: Recommended Food group change Score (RFS): Average change in the amounts of the deviations (%) from the reference food groups values (OMD = 100 %) before and after counselling taking into account the aim (eat mor/less) of the counselling session, exclusively based on the food groups addressed during counselling. Total Food group change Score (TFS): Average change in the amounts of the deviations (%) from the reference food group values (OMD = 100 %) before and after counselling based on all food groups consumed. Nutrient Improvement Score (NIS): Average change in the negative deviations (%) of 8 vitamins and 8 minerals from the German reference values for nutrient intake (Deutsche Gesellschaft für Ernährung (DGE) = 100 %) before and after counselling. On average, the intakes of the food groups mentioned during the first counselling session improved considerably (RFS = +36 %), the change in the intake of all food groups was small (TFS = +6 %) and the nutrient intakes did not improve (NIS = 0 %). From the second counselling session the values of the RFS was +10 %, of the TFS was +6% and of the NIS +3 %. This means that the success of counselling on one dietary criterion does not guarantee success on others. Our food and nutrient based scores together with a detailed food intake assessment give an example of multivariate measurements of nutrition counselling outcomes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 42
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 119-131 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary In a dietary survey, large numbers of a wide variety of food samples have to be analyzed. The atomic absorption spectroscopy (AAS), with its simplicity, accuracy and rapidity, suggests itself for determination of many elements in such a case. In this investigation, calcium determination by AAS is reviewed. Analytical parameters, interferences and their control are studied. Food samples are dry ashed and treated so as to eliminate silicates. Most serious interference comes from phosphates and is successfully controlled by addition of lanthanum. Calcium is determined in the range 2–10 ppm with a sensitivity of 0.1 ppm. Single food samples and samples representing food mixtures are analyzed, and calcium intake of different population groups is computed. In most cases, results compare favourably well with those obtained from food composition tables. Calcium intake in the Netherlands both of the average per caput and of chosen population groups is found to cover the recommendations except for infants. Differences do exist between intakes of different groups and in different seasons.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 43
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 107-118 
    ISSN: 1436-6215
    Schlagwort(e): bone ; protein deficiency ; calorie restriction ; calcium deficiency
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Es wurden Untersuchungen über die Wirkung von verschiedenen Protein- und Kalziummengen in der Diät auf das Skelett von jungen unterernährten Ratten durchgeführt. Die Ergebnisse bezogen sich auf die physischen Eigenschaften der Knochen und auf mikroradiographische Untersuchungen verschiedener Teile der Oberschenkelknochen und auf Knochengewebeschnitte. Es zeigten sich deutliche Beziehungen zwischen Niedrig-Protein-Diät und geringer Knochenmasse, unabhängig von der Kalziumeinnahme, wie auch zwischen Hoch-Protein-Diät und hoher Knochendichte bei normalem Kalziumgehalt in der Diät. Der Einfluß von Diätprotein auf die Knochenzusammensetzung war von der Kalziumeinnahme abhängig. Eine Herabsetzung der Proteinmenge wurde mit weniger spongiösem Knochengewebe in Verbindung gebracht, eine Herabsetzung der Kalziummenge verminderte hauptsächlich die Menge von kortikalem Knochengewebe.
    Notizen: Summary A study has been made of the effects of various levels of dietary protein and calcium on the skeleton of young undernourished rats. The data for the study were obtained from physical properties of bone, from microradiographs of various parts of femur and histological sections of the bone. There were significant associations between a low protein intake and low bone mass, irrespective of calcium intake, and between a high protein intake and a high bone density at a normal calcium content of the diet. The influence of dietary protein on the composition of the bone was dependent on the calcium intake. Reduction in the protein level was associated with less trabecular bone and reduction in the calcium reduced mainly the amount of cortical bone.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 44
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 20 (1981), S. 96-106 
    ISSN: 1436-6215
    Schlagwort(e): Zuckeraustauschstoffe ; Palatinit ; Karies ; Mundflora ; Tierexperiment
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Several cariogenic bacterial species, a mixed streptococci flora composed of nine species, as well as the plaque- and saliva-mixed flora from human beings were tested for acid production from the sugar substitute palatinit, which was compared to sorbitol, mannitol, xylitol and the low molecular carbohydrates sucrose, glucose and fructose. Complementary experiments with gnotobiotic and conventionally fed rats were performed in order to test the cariogenic properties of palatinit and palatinitchocolate in comparison to xylitol, sorbitol and sucrose and the corresponding chocolate substances. Palatinit and palatinit-chocolate show highly significant lower cariogenic properties than sucrose and sucrose-chocolate. On the basis of these microbiological and animal experiments, the use of palatinit as sugar substitute for caries prophylaxis can be recommended.
    Notizen: Zusammenfassung Eine Reihe kariesätiologisch wichtiger Bakterienarten, eine Streptokokken-mischflora aus 9 Arten sowie die Plaque- und Speichelmischflora des Menschen wurden im In-vitro-Versuch auf ihr Säurebildungsvermögen aus dem neueren Zuckeraustauschstoff Palatinit® überprüft. Als Vergleichssubstanzen dienten Sorbit, Mannit, Xylit und die niedermolekularen Kohlenhydrate Saccharose, Glucose und Fructose. Ergänzende Untersuchungen wurden ferner im konventionellen und gnotobiotischen Tierexperiment mit Ratten über die kariogenen Eigenschaften des reinen Palatinits und von Palatinitschokolade im Vergleich zu Xylit, Sorbit und Saccharose sowie den entsprechenden Schokoladeprodukten durchgeführt. Im Gegensatz zur Saccharose und Saccharoseschokolade zeigten Palatinit und Palatinitschokolade hoch signifikant geringere kardiogene Eigenschaften. Auf Grund dieser Versuchsergebnisse kann der Palatinit als Saccharoseaustauschstoff für den Einsatz in der Kariesprophylaxe empfohlen werden.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 45
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 241-254 
    ISSN: 1436-6215
    Schlagwort(e): Verzehrsregulation ; Sättigung ; Verzehrsverhalten
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Food intake in man and animals occurs as meals. Because changes in daily food intake in laboratory animals are often associated with corresponding changes in meal size, while meal frequency is less affected, food intake appears to be regulated mainly by the satiety mechanism. Meal size is controlled by feedback or satiety signals originating from the stomach, the small intestine, the liver and the fat depots. Both neural and hormonal (Bombesin?, Cholecystokinin?) feedback signals are elicited in the stomach and intestine. The feedback signals of the liver apparently originate from hepatic chemoreceptors, whose activity is modulated by certain metabolites, in particular glucose. The satiety effect of pancreatic glucagon, whose plasma concentration in the portal vein increases during a meal, also appears to be mediated by the hepatic chemoreceptors. Unmyelated nerve endings are probably the morphological substrate of the hepatic chemoreceptors. There is some evidence that circulating fat metabolites (fatty acids, ketone bodies, glycerol), whose plasma levels are related to the size of the fat depots, function as lipostatic feedback signals. The signal transfer from the gastrointestinal chemo- and mechanoreceptors and from the hepatic chemoreceptors to the central nervous system occurs mainly through vagal afferents. The first relay for this afferents is the nucleus tractus solitarii in the medulla oblongata. The next relay is at the pons, from where neurons project to the hypothalamus and other forebrain areas. The hypothalamus has important integrative functions in the control of food intake.
    Notizen: Zusammenfassung Die Nahrungsaufnahme erfolgt bei Mensch und Tier in Form von Mahlzeiten. Da sich Änderungen in der täglichen Nahrungsaufnahme beim Versuchstier meist in entsprechenden Veränderungen der Mahlzeitengröße, nicht aber der Mahlzeitenfrequenz manifestieren, scheint die Nahrungsaufnahme hauptsächlich durch den Sättigungsmechanismus reguliert zu werden. Die Mahlzeitengröße wird durch vom Magen, vom Dünndarm, von der Leber und von den Fettdepots ausgehende Feedback- oder Sättigungs-Signale determiniert. Die gastralen und intestinalen Feedback-Signale scheinen dabei nervaler und hormonaler (Bombesin?, Cholezystokinin?) Natur zu sein. Die Feedback-Signale der Leber gehen offensichtlich von hepatischen Chemorezeptoren aus, deren Aktivität durch bestimmte Metabolite, insbesondere Glucose, moduliert wird. Auch die Sättigungswirkung von pankreatischem Glukagon, dessen Plasmakonzentration während der Aufnahme einer Mahlzeit in der Pfortader ansteigt, kommt wahrscheinlich unter Einschaltung der hepatischen Chemorezeptoren zustande, deren morphologisches Substrat marklose Nervenendigungen sein dürften. Als lipostatische Feedback-Signale fungieren wahrscheinlich im Blut zirkulierende Metabolite des Fettstoffwechsels (Fettsäuren, Ketonkörper, Glyzerin), deren Plasmakonzentrationen mit der Größe der Fettdepots korreliert sind. Die nervale Übertragung der von den gastrointestinalen Chemo- und Mechanorezeptoren sowie den hepatischen Chemorezeptoren ausgehenden Feedback-Signale zum Zentralnervensystem erfolgt hauptsächlich über afferente Vagusfasern. Als erste Relais-Station fungiert diesbezüglich der Nucleus tractus solitarii der Medulla oblongata, von dem aus Nervenfasern über eine Relais-Station in der Pons zum Hypothalamus und anderen Vorderhirnregionen projizieren. Dem Hypothalamus scheinen bei der Regulation der Nahrungsaufnahme wichtige integrative Funktionen zuzukommen.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 46
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 23 (1984), S. 291-291 
    ISSN: 1436-6215
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 47
    Digitale Medien
    Digitale Medien
    Springer
    European journal of nutrition 38 (1999), S. 218-226 
    ISSN: 1436-6215
    Schlagwort(e): Key words Sugar alcohol – lactitol – breath hydrogen – lactose malabsorption – gastrointestinal symptons – diarrhea
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary The hydrogen breath analysis test was performed in healthy Thai adults to determine lactitol tolerance. The study was conducted in 39 individuals (11 males and 28 females) aged 18–41 years. All volunteers agreed to participate in this study after the risks and benefits had been fully explained. Subjects were requested not to consume milk, milk products, or high-vegetable diets for a day and to fast from 10 p.m. of the day preceding the test day. After consumption on the test diet (12 and 20 g of lactose or lactitol, respectively, in 250 mL water), the subjects recorded the severity of symptoms for 24 hours. Breath samples were collected after fasting and after consumption of the test diet at 30 min intervals over the 7-hour study period. Breath samples were analyzed for hydrogen using gag chromatography. After consumption of 12 g lactose, the prevalence of lactose malabsorbers was established. The increment of a peak breath hydrogen level of ≥ 20 ppm above the baseline level was used as an indicator of lactose malabsorption. The lactose malabsorbers were further classified as lactose tolerants or lactose intolerants according to the gastrointestinal symptoms observed. All 39 healthy Thai adults could be classified into 3 groups as follows: 9 (23%) lactose absorbers (LA), 15 (38.5%) lactose malabsorber/tolerants (LMT) and 15 (38.5%) lactose malabsorber/intolerants (LMI). Using the hydrogen breath test, 67% of the subjects were identified as lactitol intolerants after the consumption of 12 g lactitol. The lactitol intolerants comprised 53.8% of LMI, 34.6% of LMT, and 11.5% of LA. Among all subjects, one third of LA (33%), two thirds of LMT (60%), and 93% of LMI were lactitol intolerant. In addition, gastrointestinal symptoms such as flatulence and abdominal pain were most pronounced in LMI. Diarrhea was also a prominent manifestation after consumption of 12 g lactitol. Therefore, it was finally decided that 20 g lactose or lactitol were not given to LMI because of the risk of gastrointestinal symptoms. After high doses (20 g) of lactose and lactitol consumption, most LMT developed more symptoms than did LA and the main symptom was diarrhea. Consumption of 20 g lactose resulted in fewer symptoms than 20 g lactitol in both LA and LMT. On the basis of the hydrogen breath test, most LA tolerated 12 g lactitol without gastrointestinal symptoms except some flatulence whereas most LMT and LMI did not. Twenty g lactitol was not tolerated by both LA and LMT because there was diarrhea among the subjects, especially in LMT. Although the hydrogen breath analysis test is the best method for identification of lactose malabsorption, it is not the best method to identify lactitol intolerance. A hydrogen concentration of 15 ppm above the baseline level was found to be the best cut-off point to indicate lactitol intolerance although sensitivity was 85% and specificity only 38% in this study. It was further concluded that there is a greater susceptibility to lactitol in human lactose malabsorbers than in lactose absorbers. Our findings might be relevant for the limited use of lactitol in Thailand.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    ISSN: 1436-6215
    Schlagwort(e): Key words Ergogenics – amino acids – exercise – arginine aspartate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Athletes consume arginine and/or aspartate as potential nutritional ergogenics. Their metabolic effects are controversial and there is some evidence that ingestion of large doses of single amino acids can adversely affect the nitrogen balance or induce an amino acid imbalance. Nevertheless, the general metabolic influence of an arginine aspartate supplementation during a prolonged exercise bout has not yet been investigated. Aim of the study: The aim of this study was, therefore, to investigate the general metabolic impact of a chronic supplementation with arginine aspartate in endurance-trained athletes at rest and during a marathon run. Methods: Fourteen endurance-trained runners participated in this field study which was carried out according to a double-blind crossover design. 15 g of arginine aspartate or a carbohydrate-based placebo were supplemented daily for 14 days before a marathon run. Blood samples for analysis of metabolites and hormones were collected shortly before the run, after 31 km, at the end of the run, and after a recovery period of two hours. Additionally, the respiratory exchange ratio was determined during the run. Results: The plasma level of carbohydrate (glucose, lactate, pyruvate) and fat metabolites (fatty acids, glycerol, β-hydroxybutyrate), cortisol, insulin, ammonia, lactate dehydrogenase, and creatine kinase as well as the respiratory exchange ratio were unaffected by the supplementation. In contrast, the plasma level of somatotropic hormone, glucagon, urea, and arginine were significantly increased, and the level of most of the remaining plasma amino acids as well as their sun was significantly reduced. Conclusions: There was no obvious metabolic benefit derived from the chronic supplementation with arginine aspartate. And since furthermore the consequences of a reduction of the total plasma amino acid level are not known, the practice of using single amino acid supplements as potential ergogenics should be critically reevaluated.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 49
    ISSN: 1436-6215
    Schlagwort(e): Key words Conjugated linoleic acid – hormones – metabolites – lipoproteins – fatty acids – swine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Medizin
    Notizen: Summary Background: Conjugated linoleic acids (CLA)# refer to a group of linoleic acid (18:2)-derived isomers with conjugated double bonds mostly at carbon atoms 9 and 11 or 10 and 12, and with all possible cis and trans combinations. CLA is a newly recognized nutrient that functions to regulate energy retention and metabolism and that causes a serum lipoprotein profile considered to be less atherogenic. However, rodent models that have been frequently used for these studies are only of limited use because of distinct differences in physiology, compared with man. Additionally, possible differences in food intake between the experimental groups remained often unconsidered in those studies. Thus, it can not be excluded that the beneficial effects of CLA reported in a series of studies may be due, at least partially, to differences in nutrient and energy ingested. Aim of the study: This prompted us to undertake an investigation on the action of CLA by using a pig model and a feeding regimen with controlled amounts of food and antioxidants. The parameters used to assess CLA-specific action were selected hormones and metabolites involved in energy metabolism, individual lipoproteins and the appearance of CLA in fasting serum and erythrocyte membranes. Blood as an easily available biological sample was used for investigation. Methods: For that purpose 16 adult female pigs were divided into two groups of 8 each, and were isoenergetically fed diets containing 0 (control diet) or 1% level of CLA (by weight) for 6 weeks. Plasma concentrations of total and free thyroxine (T4), total and free triiodothyronine (T3), and insulin were measured by radioimmunoassays. Plasma non-esterified fatty acids (NEFA), β-hydroxybutyrate, circulating blood ATP and other clinical chemical variables were determined using enzymatic assays. The concentration of α-tocopherol was determined by high perfomrance liquid chromatography. The lipoproteins VLDL (density 〈1.019 kg/L), LDL (density 1.019 – 1.063 kg/L), and HDL (density 〉1.063 kg/L) were isolated by step-wise ultracentrifugation. Fatty acids of the dietary oils, serum and blood cell membranes were separated and quantified by gas chromatography. Results: At week 6, body weights of the pigs fed the CLA-supplemented diet were not different from that of the controls. CLA-treated pigs exhibited a 37% higher concentration of fasting serum insulin than their controls receiving no CLA (P = 0.11). Circulating free and total T4 and T3 as well as serum levels of β-hydroxybutyrate, α-tocopherol, protein, glucose, urea, creatinine and circulating blood ATP remained unaffected by CLA supplementation. Serum concentrations of non-esterified fatty acids were reduced by 38% in CLA-treated pigs relative to the controls, although this difference was not significant. CLA-treated pigs tended to have lower leukocyte counts in blood than their controls (P 〈0.1). Erythrocyte and platelet counts, the hematocrit and hemoglobin concentration were similar between the groups. Serum of CLA-treated pigs showed a trend toward increased levels of triacylglycerols, cholesterol and phosphatidylcholine in the very low density and low density lipoproteins (LDL), without distinct changes in the high density lipoprotein fraction (HDL). The LDL cholesterol to HDL cholesterol ratio was significantly increased by CLA. When pigs were fed CLA at a dietary level of 1%, limited proportions of CLA appeared in fasting serum (1.6%) and erythrocyte membranes (1.1%). Conclusions: Under the present experimental conditions there appeared to be parallels between the effects of CLA and the reported effects of trans fatty acids in the mode of action on lipoproteins and insulin. The failure to demonstrate significant beneficial effects of CLA on the lipoprotein profile which have been observed in other studies requires further research.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 50
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 2-19 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Corneal topography; Fluorescence; Holography; Interferometry; Moiré; Partial coherence
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. Corneal topography has, due to developments in refractive surgery and contact lens fitting, become a widely used diagnostic tool. Many types of topographers have been introduced, but there is some confusion on classification and subsequent principal possibilities of the various devices offered to the practitioner. The purpose of the study reported here was to make an inventory of developed devices, analyse the basic principles and create a classification based on optical principles. A literature search was done using Medline, the IBM Patent Server, and references found in articles and patents. This search resulted in a variety of descriptions that could be classified into 12 groups according to their use of light source and light-matter interaction of which four groups have representatives on the commercial market. This classification can be used by researchers and practitioners to gain insight into the possibilities of a given device in relation to the desired application.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 51
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Interstitial laser coagulation; Laser applicator; Laser induced thermotherapy; Liver tumours; Nd-YAG laser
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. A newly developed diffusing laser applicator was examined for interstitial laser coagulation (ILC) of liver tumours. The applicator consisted of a matted quartz core and a quartz glass dome, also matted on its inner surface and sealed to the fibre. The applicator provided a homogeneous light intensity distribution over an active length of about 20 mm. Lesions were created in an ex-vivo porcine liver model using a Nd-YAG laser comparing the new diffusing tip with a Ringmode®-ITT applicator in order to find optimal laser parameters and damage thresholds. The lesions were investigated using macroscopic size measurement, volume calculation and histological examination (H&E, NADPH-dehydrogenase). The damage threshold of the diffusing tip was 6 W at 14 min exposure time whereas the Ringmode®-ITT applicator had its limit at 5 W and 12 min exposure. Comparing various exposure times showed that treatment over a time of more than 840 s did not significantly increase the lesion volume. At 5 W and 720 s the mean lesion volume was 6.9±1.1 cm3 with the diffusing tip and 6.3±0.6 cm3 with the Ringmode®-ITT applicator, both having a slight ellipsoidal shape. Hence, the created lesions were not significantly different for both applicators when the same laser parameters were applied. On the other hand, the new diffusing tip had a higher damage threshold and was therefore capable of producing maximal coagulation volumes of up to 7.9±0.5 cm3 at 5 W and 20 min. The experiments showed that lesions with a dimension of 31×22 mm can be achieved with the diffusing applicator which seem suitably sized for treating small human liver metastases in a single laser session.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 52
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 62-66 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Laser myringotomy; Otitis media with effusion; Tympanic membrane
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. A prospective comparative study was done to assess the validity of laser myringotomy (L-myringotomy) when compared to the insertion of ventilating tubes (VT). In 23 children with chronic otitis media with effusion, a VT was inserted in the left ear while a laser myringotomy was performed in the right ear by using the CO2 Sharplan 1030 laser. After a six month follow-up conducted during the winter months, the results with the laser myringotomy were equal to those in the left ear with the VT. During the follow-up period, three ears required additional laser myringotomy either for early closure or because of otitis media and the accumulation of effusion in the middle ear cavity. Nevertheless, the use of laser has the advantage that there is no foreign body in the ear, the tympanic membrane is closed after four to seven weeks, and since the procedure is very short, the time for anaesthesia is minimal.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 53
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Chorioallantoic membrane (CAM); Liposomes; Methylene blue; Ovarian cancer; Photodynamic therapy; Photosensitiser
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. The disappointing results with either surgery alone and/or chemotherapy in the treatment of malignant ovarian tumours have led to an increased interest in additional treatment schedules. Photodynamic therapy (PDT), a modality involving the use of a photosensitising drug and activating light, is being used increasingly as a local treatment for neoplastic lesions. The synthesis and evaluation of new photosensitisers for the treatment of gynaecological lesions and malignancies continues to be an active area of investigation for proper application of the photodynamic process in the gynaecological field. The effect of PDT using methylene blue (free and combined with liposomes) as a photosensitiser for treating human ovarian malignant tumours cultivated on the chorioallantoic membrane was evaluated. Two days after PDT, the treated implanted tumours were markedly decreased in size. Areas of necrosis with black coloration, dryness and eschar formation were observed. Five days after PDT, tumour remission was clearly observed in all the treated tumours. Photodynamic therapy using methylene blue (aqueous and coupled with liposomes) is effective for treating the ovarian malignancies and it will be capable of achieving complete eradication of visible tumours in patients with superficial lesions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 54
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Aminolaevulinic acid; Dermatology; Photodynamic therapy; Photosensitisation; Protoporphyrin IX; Skin lesions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. The method of surface-detected fluorescence has been used to monitor the emission intensity from 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in lesions and corresponding adjacent normal skin. Three types of lesions were examined: psoriatic plaques, actinic keratosis and basal cell carcinoma. This study included a total of 14 human volunteers on whom ALA-induced PpIX formation and clearance was monitored for a total of 48 h post-ALA application. Both an ALA dose-ranging study, as well as a comparison of results between normal and lesional tissue at a fixed ALA dose, were carried out. For the dose range examined (10–30%), there was no ALA dose dependency of the PpIX fluorescence for any of the lesions tested. Although all three lesions tested did show enhanced PpIX fluorescence as compared with normal skin, there was considerable lesion-to-lesion variability. Thick psoriatic plaques seem to give longer PpIX retention times than those of thin lesions. Limitations of the surface-detected fluorescence methodology are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 55
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Interstitial laser therapy; Liver; Perfusion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. Interstitial laser Doppler flowmetry was used to measure the effect of interstitial laser-induced thermotherapy on local blood perfusion in normal rat liver in the peripheral treatment region elevated to hyperthermic temperatures. The Nd:YAG laser emitting at 1064 nm was utilised as heat generation source. The plane-cut tip of an optical fibre was placed in the middle of the exteriorised left liver lobe. Blood perfusion and temperature were measured in the liver parenchyma 4 mm from the laser fibre. The temperature at the location of the liver temperature sensor was maintained at 41 or 44°C during 30 min by regulating the power of the heating laser. The laser Doppler signal was recorded during and after heat treatment, for a total time of 60 min. At 41°C, a significant increase in perfusion up to 1.3 times the initial value was observed 2–16 min after start of treatment. At 44°C, perfusion decreased continuously during and after treatment, and was significantly different from control 40 min after start of treatment. The results may be valuable in assessing the thermal response of tissues surrounding the target in interstitial laser-induced thermotherapy of liver tumours during conditions of normal blood flow.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 56
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 168-174 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Endodontics; Laser ablation; Nd:YAG laser; Picosecond laser; Root canal therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . The interaction of picosecond laser radiation with human dental tissue was investigated in this study, in order to determine the ablation rates and the surface characteristics of the dentine by using scanning electron microscopy (SEM). Dentine ablation was performed by using tooth sections of different thicknesses (0.5–2.0 mm). Dental tissue samples were irradiated in air with the fundamental wavelength and first harmonic of a regenerative amplifier Nd:YAG laser system, at 1064 nm and 532 nm, respectively, with a pulse duration of 100 ps and a pulse repetition rate of 10 Hz. The results showed very clean craters surrounded by minimum melting of the surface of dentine when the 1064 nm pulses were used. In contrast, when the first harmonic 532 nm pulses were used, the SEM examinations revealed cracks and melting of dentine with irregular surface modification. Consequently, it seems that cleaning and shaping of the root canal walls during endodontic therapy with the picosecond Nd:YAG laser application may be possible in the future. The, as yet unexplored, field of the picosecond laser interaction with hard dental tissue is expected to be a potential alternative for powerful laser processing of biomedical structures.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 57
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 185-195 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Chlorins; Firing; Janus green B; Methylene blue; Neuron; Photodynamic effect; Photoheme; Photoporphyrin IX; Photosens; Photosensitisers
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . The study of single neuron response to photodynamic effect provides a means for the study of the dynamics of cytotoxic events leading to cell death and allows comparison of the phototoxicity of different photosensitisers. Isolated crayfish stretch receptor neurons were photosensitised for 30 min, then irradiated with a He-Ne laser (632.8 nm; 0.3 W/cm2) until irreversible firing cessation. The dynamics of neuron firing frequency were continuously recorded throughout. The following photosensitisers were studied: methylene blue, janus green B, protoporphyrin IX, chlorins e 6 and p 6, haematoporphyrin derivative (Photoheme) and sulphonated aluminium phthalocyanine (Photosens). Nerve cells were found to be insensitive to either He-Ne laser irradiation or photosensitisation alone, but very vulnerable to the photodynamic effect: neurons changed firing rate and died at nanomolar concentrations of photosensitisers. The dynamics of neuron responses was found to depend on photosensitiser type and concentration. The current approach provides a means of evaluation of initial threshold cell membrane alteration and cytotoxic events leading to cell death. The dependence of firing acceleration rate and neuron lifetime on photosensitiser concentration additionally allowed comparison of efficiencies of different photosensitisers. Photosens, Photoheme and chlorin p 6 were found to be the most potent photosensitisers: neurons responded to their photodynamic effects at concentrations as low as 1–5 nM.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 58
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 73-80 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Biocides; Disinfection; Laser; Optical fibre
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. In order to set up a disinfection protocol, the tip of the optical fibre of an Nd-YAP laser, λ=1.34 μm, was contaminated in vitro with: Mycobacterium smegmatis (CIP 7326), Candida albicans (ATCC 2091), Bacillus stearothermophilus (ATCC 7953) or Streptococcus sanguis (ATCC 10556). It was then treated with various biocidal solutions, Septinol® V, glutaraldehyde 2%, ethanol 95° and NaOCl 6%, using one of two protocols: 10 s of contact, or 5 s of contact followed by 5 s of wiping. The latter technique proved to be the most effective. Whatever the biocidal solution used, all the bacteria adhering to the fibre were eliminated. The protocol was checked in vivo in the canals of 10 teeth presenting root canal infections. No bacteria withstood the treatment with Septinol® V. This treatment does not alter the qualities and performance of the fibre as far as light transmission is concerned.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 59
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 105-108 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Glaucoma, open angle; Intraocular pressure; Laser surgery; Trabecular meshwork; Trabeculoplasty
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. A randomised prospective study was carried out to determine whether diode laser trabeculoplasty (DLT) is as effective as argon laser trabeculoplasty (ALT) in the control of primary open angle glaucoma (POAG). Forty eyes of 40 patients with uncontrolled intraocular pressure (IOP) despite maximum topical medication were entered into the study. Twenty eyes received DLT, spot size 100 μm, exposure time 0.2 s, mean power 1034 (±56.4) mW. Twenty eyes received ALT, spot size 50 μm, exposure time 0.2 s, mean power 528 (±44.7) mW. They were reviewed at 2 h, 2 and 8 weeks, and 3, 6, 12, 18 and 24 months after laser treatment. Two eyes were withdrawn from the DLT group and four from the ALT group because of uncontrolled IOP during follow-up. Of the remaining eyes in the trial, mean IOP reductions for DLT and ALT, respectively, were: 6 months 7.42 (±2.36) mmHg and 6.36 (±2.3) mmHg; 12 months 7.02 (±2.6) mmHg and 6.28 (±2.2) mmHg; 18 months 6.86 (±2.8) mmHg, 5.98 (±2.02) mmHg; 24 months 6.50 (±2.72) mmHg, 5.92 (±2.02) mmHg. There was a significant reduction in each laser group when IOP at each stage was compared with baseline (p〈0.001) (paired Student's t-test), but no significant difference between the two groups. In the ALT group peripheral anterior synechiae developed in four eyes and post laser pain in seven eyes. These complications were not noted following DLT. We conclude that DLT and ALT are equally effective in IOP control, but DLT is associated with less anterior segment inflammation.
    Materialart: Digitale Medien
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  • 60
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Colour-coded duplex sonography; Laser induced thermotherapy; Minimal invasive therapy; Recurrent breast cancer
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. The effect of laser-induced thermotherapy (LITT) as a palliative method for treatment of patients with local recurrence of breast cancer is investigated. This report describes the use of interstitial laser photocoagulation to manage such lesions. The interstitial laser applications were performed in seven women with locally recurrent breast carcinoma on the chest wall after mastectomy. All patients had been heavily pretreated with conventional modes of therapy (radiotherapy, chemotherapy, hormonal therapy, surgical resection). A Nd:YAG laser with a wavelength of 1064 nm was used to heat the lesions. Heat expansion was controlled digitally and monitored by ultrasonography and colour-coded duplex sonography (CCDS). In five women this minimally invasive method enabled the precise coagulation of the subcutaneous tumour without destruction of the skin or ulceration, although these areas had been pretreated by irradiation up to 60 Gy. In two patients with extensive multiple metastases and with skin infiltration, secondary skin ulceration and delayed healing was observed. For palliative reasons, LITT under CCDS guide can aid in local control of chest wall recurrence following mastectomy in selected patients.
    Materialart: Digitale Medien
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  • 61
    ISSN: 1435-604X
    Schlagwort(e): Keywords:Candida albicansCandidosis; Hyphae; Lethal photosensitisation; Toluidine blue O; Yeast
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. Oral infections due to Candida albicans are a common occurrence in patients with acquired immunodeficiency syndrome (AIDS). The purpose of this investigation was to determine whether the yeast and hyphal forms of the organism could be killed using the light-activated antimicrobial agent toluidine blue O (TBO). Three variables were investigated: TBO concentration, laser light dose and pre-irradiation time (PIT). Irradiation with light from a helium neon (HeNe) gas laser used in conjunction with the photosensitiser TBO resulted in substantial kills of both the yeast and hyphal forms. Killing was light dose-dependent with 42 J being the most effective dose. The optimum PIT for the yeast form was 5 min, whereas killing of the hyphal form was not affected by PIT. The results of this study have shown that both forms of C. albicans are susceptible to lethal photosensitisation using TBO in conjunction with HeNe laser light, suggesting the possibility that this approach could be useful for eliminating the organism from diseased lesions in vivo.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 62
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Beamsplitter; Liver; Metastases; Nd:YAG; Tumour
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . Simultaneous application of multiple fibres could increase the volume of coagulation produced with interstitial laser photocoagulation (ILP) for solid tumours. To take full advantage of the presumed synergistic thermal effect between the fibres, the optimal combination of laser power and distance between the fibres was investigated. Four fibres with a cylindrical diffusing tip of 2 cm length were used, coupled to an optical beamsplitter for Nd:YAG light (four channels, maximal variation 9.5%, transmission 〉85%). The distance between the fibres was 1, 1.5, 2, 2.5 , 3 or 4 cm with a power output of either 4, 5, 6 or 7 W/fibre; energy per fibre was constant at 1800 J by adjusting exposure time. After laser application, dimensions of the coagulated lesions were measured. The optimal mutual fibre distance was 2 cm ( p〈0.01) at all power levels. This resulted in lesions with a mean (SD) volume of 44.5 (2.1) cm3 and a largest diameter of 5.1 (0.4) cm at 7 W/fibre. Smaller distances between the fibres resulted in smaller lesions with central carbonisation, whereas larger distances resulted in four separate zones of coagulation. It was concluded that simultaneous application of four interstitial fibres may result in a considerable increase of volume of coagulation. Fibre position and mutual fibre distance determines whether synergism of the coagulative effect occurs.
    Materialart: Digitale Medien
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  • 63
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 244-246 
    ISSN: 1435-604X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 64
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 257-268 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Diffuser; Emission profile; Fluorescence imaging; Interstitial laser photocoagulation; Photodynamic therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . Cylindrical light diffusers are commercially available for clinical applications such as photodynamic therapy (PDT) and interstitial laser photocoagulation (ILP). A fluorescence imaging technique has been used to quantify the light distribution produced by each of six different diffuser fibres. The light distribution produced by each device was found to depend on the distance the light propagated in the fluorescent dye solution. At a distance of 1 mm from the diffuser midline, the measured profiles were found to be consistent with published results obtained in air at a similar distance. The three devices intended for PDT utilised scattering particles and reflectors in their construction. The profiles produced by these applicators revealed peaks that were attributed to the reflectors located at their distal tips. By comparison, the two etched ILP fibres displayed either a strong modulation in the profile due to non-uniform etching or a predominant forward peak associated with the conical shape of the tip. We conclude that it is important to take into account the forward-directed light emitted by the diffusers when considering clinical applications using these devices.
    Materialart: Digitale Medien
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  • 65
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 297-306 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Bioheat transfer equation; ILP; In vivo; LITT; Photocoagulation; Rate kinetics; Temperature distribution; Thermal lesion size; Thermotherapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . An investigation of the temperature response and growth of thermal lesions resulting from in vivo, interstitial laser photocoagulation at long exposures was conducted to assess extended lesion growth characteristics and test the applicability of first order unimolecular rate kinetics (Arrhenius theory) to thermal lesion growth. Irradiations were performed in vivo in rabbit muscle using a continuous 805 nm diode laser source operating at 1.0 W coupled to an optical fibre with a precharred tip (i.e. point heat source). Temperature responses were measured using a linear array of five microthermocouples. Each temperature–time profile was fitted to a solution of the Weinbaum–Jiji bioheat transfer equation (W–J BHTE). Lesions were resected 48 h post-irradiation and the necrosis boundaries were determined histologically. Numerical integration of the Arrhenius damage integral using temperature–time data at the lesion boundary produced corresponding pairs of activation energy and pre-exponential factor (E a, α) consistent with reported values for various other end-points and tissue types. Lesion radii were 6.0±0.6, 8.7±0.4 and 9.7±0.5 mm for 10, 20 and 30 min irradiations respectively. Thermal lesion growth predicted from Arrhenius theory was consistent with experimental results and is non-asymptotic by 30 min. Thermal parameters generally assumed to be constant when solving the W–J BHTE were found to vary with radial distance from the source, presumably due to a temperature dependence.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 66
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 20-23 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Diode laser; Expandable metal stent; Malignant dysphagia; Nd-YAG; Overgrowth; Tumour in-growth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. Re-establishment of the oesophageal lumen is the main focus of care in patients with dysphagia due to re-blockage of in situ expandable metal stent (EMS). A total of 51 patients aged 44–89 years were intubated with EMS for dysphagia due to inoperable oesophagogastric carcinoma. Of these patients, 25 required follow-up endoscopy at variable intervals after stent insertion; 17 patients were found to have significant tumour in-growth (9), overgrowth (4) or both (4). All these patients were treated with Nd-YAG (70 W/s) or diode laser (30–50 W, continuous) for maintenance of satisfactory swallowing. The intensity of tumour ablation was similar with both types of lasers but four patients being treated with Nd-YAG laser developed deformity of EMS. This complication was not encountered with diode laser. The timing of the stent insertion should be carefully chosen since the longer the stent is in situ, the greater is the likelihood of tumour ingrowth or overgrowth. The combination of endoscopic laser therapy (ELT) and EMS may offer the best palliation, particularly when patient survival of several months is anticipated. ELT can effectively deal with tumour in-growth and overgrowth but care must be exercised in the use of Nd-YAG which can damage the structure of the EMS.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 67
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 86-90 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Benign prostatic hyperplasia; Enucleation; Holmium; Laser; Prostatectomy; Resection
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. At a wavelength of 2140 nm, the holmium:YAG (Ho:YAG) laser can be used for incision, ablation and resection of prostatic tissue. This laser has revolutionised the surgical management of benign prostatic hyperplasia (BPH) in our institution. Five different techniques have been utilised in evolving the current techniques using the Ho:YAG laser either alone or in combination with neodymium:YAG (Nd:YAG laser for the surgical management of BPH. The clinical outcome of 664 patients undergoing these procedures is presented. Enucleation of the prostatic adenoma using the holmium laser energy is the most common procedure presently performed at our institution for the surgical management of BPH. A mechanical tissue morcellator appears to be the most efficient way to remove prostatic tissue, once enucleated, from within the bladder.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 68
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 129-135 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Microcirculation; Mono-l-aspartyl chlorin-e-6 (Npe-6); Photodynamic therapy (PDT); Vascular shut-down
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract. An experimental system that allows the white light observation of rapid changes in vessels without disturbance by red laser light was used. Mice were injected with mono-l-aspartyl chlorin-e-6 (Npe-6) i.v. via the tail vein and were immediately exposed to laser light. White emboli were observed forming on the inside of the vessel walls within seconds after commencement of light exposure. Emboli adhered to vessel walls and caused vascular obstruction. Light microscopy of the exposed material using fibrin staining was performed. Electron microscopy on the same material was also carried out. The embolisation time was influenced by both drug dose and laser power. With low laser power, it took a long time to stop the blood flow. Fibrin staining revealed the white emboli to be composed of fibrin. Electron microscopy findings revealed damage to endothelial cells and platelet aggregation. This study suggests that two main mechanisms (direct cellular damage and vascular shut-down ) might actually be complementary and synergistic in the production of vascular lesions using photodynamic therapy.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 69
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 167-167 
    ISSN: 1435-604X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 70
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 175-176 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Laser; Spider naevus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . A total of 112 spider naevi in 86 patients were treated with the tunable dye laser with a wavelength of 585 nm and pulse duration of 450 µs (SPTL 1, Candela Corporation, Wayland, MA). Complete ablation of the spider telangiectasia was achieved in 81 lesions (72.3%) partial ablation was achieved in 27 lesions (24.1%) and four (3.6%) lesions had no response to treatment. Transient hyperpigmentation was noted in one patient and minimal scarring in the form of a slight depression over the treated area was noted in another patient. The pulsed dye laser is shown to be effective in the treatment of spider naevi.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 71
    Digitale Medien
    Digitale Medien
    Springer
    Lasers in medical science 14 (1999), S. 203-206 
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Carbon dioxide laser; Epulis fissuratum; Laser; Vestibuloplasty
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . There have been numerous surgical techniques developed for removing the epulis fissuratum lesions in order to improve alveolar ridge contour and improving adaptation of full prostheses. Most of these techniques can cause postoperative complications, such as oedema, pain, difficulty in swallowing and jaw movements, haemorrhage, infections and slow placement of final prostheses. The use of carbon dioxide (CO2) laser for the surgical removal of epulis lesions has resulted in many significant improvements including convenient mucosa removal, no bleeding or need for sutures, and minimal postoperative pain and oedema. This study is of 15 cases of removal of extensive epulis with vestibuloplasty in the maxilla and mandible that was carried out with CO2 laser, with no postoperative complications, rapid healing, and excellent aesthetic and functional outcome, all of which allowed for more rapid placement of final prosthesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 72
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Feedback control; Indocyanine green dye; Laser-activated solid protein solder strips; Nerve repair; Temperature monitoring; Tensile strength
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . Laser-activated solid protein solder strips have been developed for peripheral nerve repair. Indocyanine green dye added to the solder strongly absorbs diode wavelengths (∼800 nm) and causes localised heating and coagulation of the albumin protein solder. The protein strengthens the tissue join, particularly during the acute healing phase postoperative, while shielding the underlying axons from excessive thermal damage. In this investigation of the solid protein solder technique for nerve repair, the effect of laser irradiance on weld strength and solder and tissue temperature were studied. The tensile strength of repaired nerves rose steadily with increased irradiance reaching a maximum of 105±10 N/cm2 at 12.7 W/cm2. At higher irradiances, tensile strength fell. The maximum temperature reached at the solder surface and at the solder/nerve interface, measured using a non-contact fibre optic radiometer and thermocouple, respectively, also rose steadily with laser irradiance. At 12.7 W/cm2, the temperatures reached at the surface and at the interface were 88±5°C and 71±4°C, respectively. This in vitro investigation demonstrates the feasibility of the laser-activated solid protein solder strips for peripheral nerve repair. The laser irradiance and the corresponding solder surface temperature for optimal tensile strength have been identified.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 73
    ISSN: 1435-604X
    Schlagwort(e): Keywords: Adenocarcinoma; Aminolaevulinic acid; Barrett's oesophagus; Dysplasia; Photodynamic therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Physik , Technik allgemein
    Notizen: Abstract . Photodynamic therapy (PDT) may have a role in the prevention of oesophageal cancer. Ten patients with Barrett's oesophagus, three with low-grade dysplasia (LGD), four with high-grade dysplasia (HGD), one with carcinoma in situ and two with invasive carcinoma, were treated with PDT. All received 30 mg/kg aminolaevulinic acid (ALA) followed 4 h later by laser endoscopy. Half were treated with red light (630 nm; 100 mW/cm2 for 1000 s) and half with green light (514 nm; 100 mW/cm2 for 500 s). Columnar epithelial regression was seen in all patients with dysplasia (mean area decrease 44%; range 10–100%), with apparent elimination of dysplasia in all cases. In patients with in situ or invasive carcinoma, no response was seen. ALA-induced PDT, using either red or green light, produces effective ablation of dysplastic Barrett's oesophagus, hence may have a role in the prevention of oesophageal carcinoma, but has little effect on in situ or invasive adenocarcinoma.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 74
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 91-92 
    ISSN: 1572-8781
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 75
    ISSN: 1572-8781
    Schlagwort(e): tumor pathology semiconductor microfabrication microfluidics nanolasers ; nanotechnology cytometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract Through recent interdisciplinary scientific research, modern medicine has significantly advanced the diagnosis and treatment of disease. However, little progress has been made in reducing the death rate due to cancer, which remains the leading cause of death in much of the world. Pathologists routinely rely on microscopic examination of cell morphology using methods that originated over a hundred years ago. These staining methods are labor-intensive, time-consuming, and frequently in error. New micro-analytical methods1 (JBM, 1998; Harrison et al., 1993; Ramsey et al., 1995; Mauro Ferrari, Lynn Jelinski, 1994; Anderson et al., 1996; Carlson et al., 1996) for high speed (real time) automated screening of tissues and cells are critical to advancing pathology and hold the potential for improving diagnosis and treatment of cancer patients. By teaming experts in semiconductor physics, microfabrication, surface chemistry, film synthesis, and fluid mechanics with microbiologists and medical doctors, we are investigating nanostructured biochips to assess the condition of tumor cells by quantifying total protein content. This technique has the potential to quickly identify a cell population that has begun rapid protein synthesis and mitosis, characteristic of tumor cell proliferation. By incorporating microfluidic flow of cells inside the laser microcavity for the first time, we have enabled high throughput screening of cells in their native state, without need of chemical staining, in a sensitive nanodevice.
    Materialart: Digitale Medien
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  • 76
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 1 (1999), S. 97-98 
    ISSN: 1572-8781
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 77
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 1 (1999), S. 107-112 
    ISSN: 1572-8781
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract The use of microfabricated DNA analysis tools utilizing microfluidics will provide the next generation of inexpensive DNA diagnostics. It will also provide methodologies to measure gene expression in a massively parallel manner, eventually providing the methodologies to measure most or all the human genes of significance on a single chip. These technologies, including PCR analysis, electrophoresis and gene chips are described using examples from the archival literature.
    Materialart: Digitale Medien
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  • 78
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 1 (1999), S. 139-153 
    ISSN: 1572-8781
    Schlagwort(e): array biosensor ; automation ; CCD imaging ; fluorescence imaging ; antibody patterning ; waveguide
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract Optical and fluidics systems have been developed as central components for an automated array biosensor. Disposable planar waveguides are patterned with immobilized capture antibodies using a physically isolated patterning (PIP) method. The PIP method enables simultaneous deposition of several antibodies and completely circumvents cross-immobilization problems encountered with other array deposition processes. A multi-channel fluidics cell allows numerous assays to be performed on the patterned waveguide. The sensing arrays are optically interrogated using a diode laser with a tailored output to optimize coupling to and maximize excitation uniformity within the waveguide. A patterned cladding is employed to optically isolate the waveguide from perturbations induced by the permanently attached flow cells. Compact optics image the evanescently excited fluorescence onto a large area, cooled CCD array. The image data is processed and automated signal analysis corrects for local background and noise variations.
    Materialart: Digitale Medien
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  • 79
    ISSN: 1572-8781
    Schlagwort(e): drug discovery ; CellChip ; high content screening ; fluorescence ; patterning ; sensors ; microarrays ; bioinformatics ; tissue engineering
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract A major bottleneck to the early stages of drug discovery is the absence of integration of high throughput screening (HTS) with smarter assays that screen “hits” from HTS to identify leads (High content screening, HCS). We propose a solution using novel fluorescent engineered protein biosensors integrated into a miniaturized live-cell-based screening platform (CellChip™ System) that markedly shortens the early drug discovery process. Microarrays of selectively localized living cells, containing engineered fluorescent biosensors, serve to integrate HTS and HCS onto a single platform. HTS “hits” are identified using one biosensor while reading the whole chip array of cells. The high-biological content information is then obtained from probing target activity at inter-cellular, sub-cellular and molecular levels in the “hit” wells. HCS assays yield temporal-spatial dynamic maps of the drug-target interaction within each living cell. We predict that a new platform incorporating HTS and HCS assays that are automated, miniaturized, and information-rich will dramatically improve the decision making process in the pharmaceutical industry and optimize lead compounds during the early part of the drug discovery process. There is an opportunity to establish a new paradigm for drug discovery based on integration of fluorescence technology, micropatterning of living cells, automated optical detection and data analysis, and a new generation of knowledge building bioinformatics approaches. The technology will have an expansive impact spanning the fields of drug discovery, biomedical research, environmental monitoring, life sciences, and clinical diagnostics. The integrated CellChip™ Platform with miniaturized tissue-specific microarrayed cells capable of providing inter-cellular and sub-cellular spatio-temporal information in response to drug-cell, toxin-cell, or pathogen-cell interactions will serve to enhance the decision making process in drug discovery, toxicology, and clinical diagnostics.
    Materialart: Digitale Medien
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  • 80
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 145-150 
    ISSN: 1572-8781
    Schlagwort(e): electroporation ; micro-electroporation chip ; cell membrane electrical currents
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract Electroporation is commonly used in biotechnology to introduce macromolecules into cells. We have developed a micro-electroporation chip that incorporates a live biological cell in the electrical circuit. The chip configuration forces electrical currents to pass through the cell, thereby producing electrically measurable information about the electroporation state of the cell. The cell membrane electrical properties make the cell function as a diode in the electroporation current-voltage range. The chip is transparent in the area of the cell to allow microscope viewing. during electroporation. This chip may be used to study the fundamental biophysics of cell electroporation and in biotechnology for controlled macromolecule introduction in individual cells. We describe the chip principle and show results on the electrical current-voltage pattern during reversible and irreversible electroporation in individual cells.
    Materialart: Digitale Medien
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  • 81
    ISSN: 1572-8781
    Schlagwort(e): MPC ; BMA ; AMPS ; biocompatibility ; cellulose triacetate ; diffusion-limiting effect ; glucose sensor ; needle type ; glucose oxidase ; serum ; whole blood
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract A multifunctional membrane with biocompatibility, diffusion-limiting effect, and the ability to curtail the responses of an H2O2 electrode to ascorbate and urate was prepared. It was composed of MB, AB, and CTA, where MB is the copolymer of 2-methacryloyloxyethyl phosphorylcholine (MPC) and n-butylmethacrylate (BMA), AB is the copolymer of acrylamide-2-methylpropane sulfonic acid (AMPS) and BMA, CTA is cellulose triacetate. Investigation of the biocompatibility of this membrane showed that, compared with CTA, relatively few platelets bound to it. The membrane was coated onto the working electrode of a needle-type glucose sensor on which immobilized glucose oxidase membrane has been coated. The sensor did not respond to ascorbate and urate at their concentration normally encountered in blood. Its response was not inhibited by metal ions in blood at usual concentration. The sensor exhibited superior thermostability in addition to a rapid response (〈90 seconds in batch operation), good reproducibility (RE〈5%), good stability (more than 36 hours continuously in heparinized whole blood), and a wide dynamic range (5–650 mg/dl glucose). The sensor was used to determine glucose in serum. The data obtained from the sensor showed good agreement with that from a clinical autoanalyzer (R=0.973).
    Materialart: Digitale Medien
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  • 82
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 87-88 
    ISSN: 1572-8781
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 83
    ISSN: 1572-8781
    Schlagwort(e): nondestructive testing ; evanescent microwave imaging ; quantitative testing ; conductivity in biomaterials ; high resolution imaging ; material non-uniformity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract Scanning tunneling and atomic force microscopes (STM and AFM) are used to study biological materials. These methods, often capable of achieving atomic resolutions, reveal fascinating information regarding the inner workings of these materials. However, both STM and AFM require physical contact to the specimen. In the case of STM, the specimen needs to be conducting as well. Here we introduce a new method for imaging biological materials through air or a suitable liquid using decaying or evanescent fields at the tip of a properly designed microwave resonator. This novel method involves the use of an evanescent microwave probe (EMP) and is capable of imaging a variety of non-uniformities in biological materials including conductivity, permittivity, and density variations. EMP is a non-contact and non-destructive sensor and it does not require conducting specimens. Its spatial resolution is currently around 0.4 μm at 1 GHz. We have used this probe to map non-uniformities in a variety of materials including metals, semiconductors, insulators, and biological and botanical samples. Here we discuss applications of EMP imaging in bone, teeth, botanical, and agricultural specimens.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 84
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 1 (1999), S. 121-130 
    ISSN: 1572-8781
    Schlagwort(e): electrochemical actuation ; micropump ; liquid dosing ; gas bubbles
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract In this paper a micromachined electrochemically driven pump capable of dosing precise nanoliter amounts of liquid is presented. The pump consists of a micromachined channel structure realized in silicon by reactive ion etching. On top of this structure a Pyrex® cover piece with noble metal electrodes was bonded. The fluid to be dispensed is stored in a meander shaped reservoir which is part of the channel structure. This meander starts in an electrolyte solution containing reservoir, on top of which two noble metal electrodes are positioned. By the electrochemical production of gas bubbles by electrolysis of water at these electrodes, liquid can be driven out of the meander. The measured volume displacements were in close agreement with theory. Pump rates as low as a few nl/s could accurately be controlled via the actuation current through the electrodes. By applying current pulses rather than a continuous current, preset amounts of fluid in the nanoliter range could be dosed successfully. Because the resulting device consists of simple channel structures and metal electrodes it can easily be integrated in miniaturized chemical analysis systems to dose reagents or calibration solutions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 85
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 9-10 
    ISSN: 1572-8781
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 86
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 51-60 
    ISSN: 1572-8781
    Schlagwort(e): magnetoelastic ; remote query ; microdevice ; sensor ; glucose
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract Magnetoelastic thin-film sensors can be considered the magnetic analog of an acoustic bell: in response to an externally applied magnetic field impulse the sensors ring like a bell, emitting magnetic flux with a characteristic resonant frequency. The magnetic flux can be detected remotely, external to the test area, using a pick-up coil. By monitoring changes in the characteristic resonant frequency of the sensor multiple environmental parameters can be measured. In this work we report on application of magnetoelastic sensors for remote query measurement of temperature, pressure, viscosity and, in combination with a glucose-responding mass-changing polymer, in situ measurement of biological-level glucose concentrations. The advantage of using magnetoelastic sensors is that they are monitored remotely, without the need for direct physical connections such as wires or cables, nor line-of-sight alignment as needed with optical detection methods. The remote query capability allows the magnetoelastic sensors to be monitored from inside sealed, opaque containers. Depending upon the application magnetoelastic sensors can be sized from micrometer to millimeter dimensional scales, and have a material cost of approximately $0.001 allowing for their use on a disposable basis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 87
    Digitale Medien
    Digitale Medien
    Springer
    Biomedical microdevices 2 (1999), S. 41-49 
    ISSN: 1572-8781
    Schlagwort(e): cell sorting ; travelling wave dielectrophoresis ; filed-flow-fractionation ; computer microvision
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Technik allgemein
    Notizen: Abstract We describe a microfluidic device for separating cells according to their dielectric properties by combining 2-dimensional dielectrophoretic forces with field-flow-fractionation. The device comprises a thin chamber in which a travelling-wave electrical field is generated by a planar, multilayer microelectrode array at the bottom. Under the balance of gravitational and dielectrophoretic levitation forces, cells introduced into the device are positioned at different equilibrium heights in a velocity profile established inside the chamber, and thereby transported at different velocities by the fluid. Simultaneously, cells are subjected to a horizontal travelling-wave dielectrophoretic force that deflects them across the flow stream. The 2-dimensional dielectrophoretic forces acting on cells and the associated velocities in the fluid-flow and travelling-field directions depend sensitively on cell dielectric properties. The responses of cultured MDA-435 human breast cancer, HL-60 human leukemia and DS19 murine erythroleukemia cells, and of peripheral blood mononuclear (PBMN) cells were studied as functions of the frequency and voltage of the applied electric signals, and of the fluid flow rate. Significant differences were observed between the responses of different cell types. Cell separation was demonstrated by the differential redistribution of MDA-435 and PBMN cells as they flowed through the device. The device can be readily integrated with other microfluidic components for microscale sample preparation and analysis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 88
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 51-52 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Crude extracts ofSquilla mantis eyestalks have no neurodepressing activity in theProcambarus bouvieri bioassay. However, partially purified extracts show a very high level of neurodepressing hormone with the same characteristics as the decapod hormone.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 89
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 88-91 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary From the roots ofEuphorbia cyparissias L. a highly irritant diterpene ester fraction was isolated and further resolved into its constituents. Together with some less active and some inactive isomers, the pure Euphorbia factors were characterized as new diesters of 13-hydroxyingenol and as triesters of the new 13,19-dihydroxyingenol. The Euphorbia factorsCy 6,Cy 11 andCy 14 are the strongest irritants of the ingenane ester type hitherto known,Cy 11 being at least as active as the standard diterpene ester type irritant 12-O-tetradecanoylphorbol-13-acetate (TPA).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 90
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 95-96 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary It is suggested that although the high oxygen affinity hemoglobin (Hb LR) (β143(H21)His→Gln) with stabilization of R quaternary conformation is not more susceptible to the oxidizing effect of nitrites in vitro, in an in vivo situation where hemoglobin is partly deoxygenated, it might be more susceptible to methemoglobin formation due to higher oxidation and lower reduction rate.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 91
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Estradiol (E2) was specifically localized by immunocytochemistry in the cytoplasm and in the nucleus of the gonadotropic cells. The immunocytochemical reaction was not observed after injection of moxestrol, but it was not modified by injection of testosterone, progesterone, or dexamethasone. These data suggest that E2 might be bound to a high-affinity binding-site which could also have a hormonal specificity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 92
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immobilized dimers of yeast glyceraldehyde-3-phosphate dehydrogenase covalently bound to sepharose were shown to form hybrids with soluble dimers of the homologous enzymes present in crude tissue extracts (rat skeletal muscle, rat, rabbit and bovine hearts, rat liver, rat brain). Immobilized hybrid tetramers were then dissociated to form purified soluble enzymes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 93
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 71-72 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The photic energy penetrating into the brain was increased in adult rats sustaining craniotomies sealed with transparent plastic. After blinding, these animals failed to entrain their circadian food intake rhythm to light-dark cycles. Short pulses of light did not phase-shift the freerunning rhythm. We conclude that adult rats lack brain photoreceptors mediating entrainment of circadian rhythms.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 94
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1089-1090 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The delay in blood pressure increase observed in spontaneously hypertensive rats following bilateral renal denervation appeared to be due to a temporary reduction of the renal catecholamines content.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 95
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1092-1093 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Impromidine and dimaprit, two newly-synthesized histamine H2-receptor agonists, have been shown to produce a prostaglandin-mediated contraction in the isolated rat stomach fundus.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 96
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1095-1096 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The effect of suloctidil (1-(4-isopropylthiophenyl)-2-n-octylaminopropanol) on increased blood viscosity was studied in healthy volunteers after forearm occlusion. A significant reduction of blood viscosity was observed in subjects treated 1 day before, or immediately before, the ischaemic trial. It is concluded that the drug may preserve the deformability of erythrocytes during an ischaemic episode.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 97
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1097-1099 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The present report deals with the effect of excessive ingestion of fluoride on glycosaminoglycan (GAG). Increase in fluoride deposition in bone, and in circulating levels of fluoride in serum, are also reported. Among the 3 constituents of GAG investigated; hexosamine, uronic acid and sulphate, the content remained unaltered except for sulphate.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 98
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1102-1103 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary There are 4 stages in the growth of mosaic (axial) muscle, which is the predominating tissue in trout; the stages are distinguishable by the modal values and range of their fibre diameters over the size range 2.3 to 50+cm fork length. Up to 50 cm, most of the increase in mosaic muscle is attributable to continuous recruitment of new fibers. Beyond 50 cm, further growth is a result of increase in diameter of existing fibers.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 99
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1105-1106 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The eye region of mouse embryos, irradiated with 90 rad X-rays on day 8 of gestation, was examined 24 h later for cellular damage. Besides the overall developmental retardation, the radiation insult decreased the proliferation rate and altered the mitotic phase ratio. Due to the limited extension of necrotic zones, a reduced number of dead cells was found in the irradiated optic vesicles.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 100
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 37 (1981), S. 1109-1110 
    ISSN: 1420-9071
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The behavioral effects of a plasma protein fraction used as a plasma expander were determined in rats at various blood replacement levels. Results of operant conditioning tests indicated that significant treatment effects occurred on the first 3 days following transfusion. Initial decrements in performance were directly related to the lowered hematocrit levels following transfusion.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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