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  • Coleoptera  (6)
  • Bone  (5)
  • Gas chromatography  (4)
  • Electron microscopy
  • Springer  (17)
  • Annual Reviews
  • Oxford University Press
  • 1980-1984  (17)
  • 1975-1979
  • 1981  (17)
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Schlagwörter
Verlag/Herausgeber
Erscheinungszeitraum
  • 1980-1984  (17)
  • 1975-1979
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Entomologia experimentalis et applicata 30 (1981), S. 151-156 
    ISSN: 1570-7458
    Schlagwort(e): Xyleborus ferrugineus ; pupae ; ecdysteroids ; pharate adult ; radioimmunoassay ; Coleoptera ; Scolytidae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Ecdysteroidtiter weiblicher Puppen von Xyleborus ferrugineus (Fabr.) wurde geschätzt, indem ganze Tiere homogenisiert und radioimmunologisch untersucht wurden. Ein ausgeprägtes Maximum an Ecdysteroiden wurde bei 36 Stunden Puppenent-wicklung beobachtet (743 pg/mg Körpergewicht). Der Titer nahm ab auf 299 pg/mg im Pharatstadium und auf 193 pg/mg unmittelbar vor Schlüpfen der Adulten. Qualitative Studien mit HPLC ergaben in frischen Puppen ein Verhältnis von 3:1 Ecdyson zu 20-Hydrooxyecdyson. Pharatstadien enthielten vor allem 20-Hydrooxyecdyson. Das beobachtete einzige Maximum im Titer stimmt überein mit den Resultaten bei andern untersuchten Coleopteren.
    Notizen: Abstract Ecdysteroid titers were estimated on the whole body homogenates of Xyleborus ferrugineus (Fabr.) female pupae during development by radioimmunoassay. A distinct peak of ecdysteroids was observed at 36-hr pupal development (743 pg/mg body wt). Titer declined to 299 pg/mg by the pharate adult stage and to 193 pg/mg body wt just before adult emergence. Qualitative studies by HPLC revealed a ratio of 3:1 ecdysone to 20-hydroxyecdysone in the initial pupal stage. Pharate adults had mainly 20-hydroxyecdysone. The observed single peak in ecdysteroid titer agrees with findings in other studied coleopteran species.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 369-374 
    ISSN: 1432-0827
    Schlagwort(e): Histomorphometry ; Bone ; Reproducibility
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary To study bone histomorphometry reproducibility in normal subjects, we performed during orthopedic surgery bone biopsies in 16 post-menopausal women. Each woman had four bone biopsies, two at the usual site in the iliac crest, one on the left and one on the right side, and two other biopsies just behind the usual site, one at each side. We performed measurements of trabecular bone volume, relative osteoid volume, osteoid surfaces, osteoclastic resorption surfaces and calcification front. The average values of the 16 patients were compared, on the one hand, two by two, by a student test, and on the other hand, by a variance analysis. By these two methods the results showed no significant difference between the average values of the 16 patients at each location for any of the histomorphometric parameters studied. However, there was a location variation which was estimated by the intra-individual variation for a given patient. On the other hand, we calculated from the variance analysis the location variance for a group of 10 to 100 patients. In any case all the parameters had a location variation which was high for osteoclastic resorption surfaces and relative osteoid volume when expressed in % of the absolute value of these parameters. The variation of the trabecular bone volume was 0–46. 15% (95% confident limit interval) in a single patient and the hypothetical value of the location variation was 41.6% for a group of 10 patients and 13.0% for a group of 100 patients.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 381-384 
    ISSN: 1432-0827
    Schlagwort(e): Alcohol ; Electron microscopy ; Growth plate
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary We have previously demonstrated that ethanol has a direct toxic effect on the rat skeleton characterized by decreased trabecular bone volume. In the present study, we examined the ultrastructure of the distal radial epiphyseal growth plates in these same animals. Eight weeks of ethanol administration to 12 male rats results in serum alcohol levels of 140 mg/dl but did not alter the width or light microscopic appearance of the radial growth plate. Quantitative electron microscopy failed to demonstrate morphologic evidence of toxicity in the skeletal cells. We conclude that although ethanol appears to have a direct effect on rat bone characterized by enhanced resorption, toxicity is not attended by ultrastructural changes in the skeletal cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 89-99 
    ISSN: 1432-0827
    Schlagwort(e): Soluble proteoglycans ; Resistant proteoglycans ; Collagen ; Bone ; Cartilage
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary Soluble proteoglycans (SPG) were extracted from bovine (BCC) and human (HCC) costal cartilages by the dissociative method using 4 M guanidinium chloride (GuHCl). Proteoglycans which are resistant to extraction (RPG) were obtained following collagenase digestion or hydroxylamine treatment of the cartilage residues. Similarly, SPG were extracted from bovine metaphyseal and cortical bone using EDTA. The RPG were extracted from the bones using hydroxylamine. Density gradient fractionation under dissociative conditions of cartilage SPG and RPG followed by chromatography on Sepharose 2B revealed that A1D1 RPG are smaller than the SPG. SPG reacted with either collagenase or hydroxylamine are also smaller than the parent SPG. A1D1 fractions obtained from BCC-SPG and RPG or from mixtures of SPG and acid-soluble collagen are free of hydroxyproline. Hydroxyproline is not completely separated from HCC-RPG. Density gradient fractionation of bone proteoglycans and Sepharose chromatography of the A1 and A1D1 fractions showed that those obtained from metaphysis are larger than those from cortical bone. This was attributed to the presence of calcified cartilage in metaphyseal bone. The A1D1 fractions of the metaphyseal proteoglycans seemed to undergo self-association since this fraction is larger than the A1 fraction from which it is derived. Cortical bone proteoglycans do not behave similarly. Density gradient purification under dissociative conditions failed to separate hydroxyproline from the proteoglycans obtained from bone. It is hypothesized that in bone proteoglycans and collagen might be linked.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 499-504 
    ISSN: 1432-0827
    Schlagwort(e): Bone ; Collagen ; Density
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary The density of a bovine cortical bone matrix sample was found in water, several ethanol-water solutions, and in the dried state. Previously the density of the same mineralized bone was found fresh and when desiccated. The volume in each state was estimated from the dimensional changes axially, tangentially, and radially. Confirmation was found by determining the density of dried specimens upon immersion in xylene. The amount of imbibed xylene provided an estimate of the free pore volume in the dried matrix. The volume fraction of the solid constituent, S, in the wet matrix was found to be 0.57, from which the density of S in various solutions was calculated. Density of wet matrix in 0.15 M saline: 1.180 g/cc; for dried matrix, 1.246 g/cc. Density of wet S in saline: 1.33 g/cc; for dried S, 1.42 g/cc, which matches published values for collagen molecules. Dimensional changes between wet and dried state of matrix match published values for artificially cross-linked rat tail tendon fibers. Axially: 1.04, by area: 2.27; by volume: 2.62. Estimate of intrafibrillar volume, assuming 80% of mineral is within fibrils: 0.73 cc/g dry collagen.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 631-639 
    ISSN: 1432-0827
    Schlagwort(e): Bone ; Osteopenia ; Noninvasive monitoring
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary Radiological techniques were utilized for monitoring progressive changes in compact bone in the tibia of monkeys during experimentally induced osteopenia. Bone mass loss in the tibia during restraint was evaluated from radiographs, from bone mineral analysis, and from images reconstructed from gamma ray computerized tomography. The losses during 6 months of restraint tended to occur predominantly in the proximal tibia and were characterized by subperiosteal bone loss, intracortical striations, and scalloped endosteal surfaces. Bone mineral content in the cross section of the tibia declined 17–21%. Tomography demonstrated endosteal widening and reduced mineral content per unit of thickness of cortical bone. In 6 months of recovery, the mineral content of the proximal tibia remained depressed. Effects of the dynamic environment on local-regional changes in various skeletal areas are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 35-39 
    ISSN: 1432-0827
    Schlagwort(e): Copper ; Resorption ; Bone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary An investigation of the role of copper in bone metabolism was undertaken. Explanted calvaria from 6-day-old mice were grown for 48 h in medium with and without the addition of copper sulfate. Active resorption was found to be significantly inhibited in the presence of copper sulfate concentrations of 10−6M and above. Copper sulfate concentrations of 10−5M and above inhibited hydroxyproline, protein, and DNA synthesis. Lower concentrations were ineffective. The effect of 5 × 10−6M copper sulfate on resorption was reversible. Several other compounds were tested for similar effects and at 5 × 10−6M were found to inhibit bone resorption in the order: copper sulfate 〉 brown gold chloride 〉 sodium aurothiomalate 〉 zinc sulfate 〉 sodium sulfate. The copper sulfate effect was twice that of sodium aurothiomalate, and sodium sulfate was not significantly inhibitory. The results suggest that the high serum copper levels associated with rheumatoid arthritis may reflect the activity of a hypothetical control mechanism of bone resorption. In the diseased state this would act to restore the normal rate of bone resorption.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 33 (1981), S. 119-124 
    ISSN: 1432-0827
    Schlagwort(e): Avian eggshell ; Microstructure ; Electron microscopy ; Electron diffraction ; Calcite growth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Notizen: Summary The eggshell of the domestic fowl has been studied by transmission electron microscopy and diffraction. Thin sections of shell were prepared by chemical and ion-beam thinning techniques. Each calcite column of the palisade layer consisted of crystallites of diameter 20 to 30 µm with some tendency for crystallite alignment within a single column. Evidence indicates that there was no significant preferred orientation in the palisade layer as a whole. Only in the surface layer was any preferred orientation detected, and here {1014} planes tended to lie parallel to the surface. The results are compared with previously published data, and calcite nucleation and growth are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Journal of chemical ecology 7 (1981), S. 39-48 
    ISSN: 1573-1561
    Schlagwort(e): Insect feeding deterrents ; antifeedants ; Pissodes strobi Peck ; Coleoptera ; Curculionidae ; Thuja plicata Donn
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The feeding deterrent activity of fractions from the foliage of western red cedar,Thujaplicata Donn, was studied in laboratory bioassays using the white pine weevil,Pissodes strobi Peck, as a test insect. The most active fraction was the volatile mixture that comprises the leaf oil of this tree species. Further fractionation of the leaf oil indicated feeding deterrent activity in the monoterpene hydrocarbon, thujone, and terpene alcohol fractions. When tested alone, both (−)-3-isothujone and (+)-3-thujone, which made up 75–88% and 5–10% of the leaf oil, respectively, deterred feeding by the weevils. Western red cedar leaf oil also showed antifeedant activity with the alder flea beetle,Altica ambiens (Le Conte), and served as an oviposition deterrent for the onion root maggot,Hylemya antiqua Meigen. The leaf oil, however, had no inhibitory effect on the feeding of the leaf roller,Epinotia solandriana L., and the red-backed sawfly,Eriocampa ovata L.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Chromatographia 14 (1981), S. 19-22 
    ISSN: 1612-1112
    Schlagwort(e): Teflon columns ; Chemically modified teflon ; Gas chromatography ; Capillary columns
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Summary Wall-coated open tubular columns prepared from chemically modified teflon tubing have been developed for gas chromatography. Chemical reaction of the inner walls of teflon tubing allows bonding of an adhesive layer on which a variety of stationary phaes can be coated. Test mixtures of alkanes and alcohols were used to investigate the chromatographic properties of these columns and the stability and mixing of the adhesive and stationary phae layers. the results in dicate that mixing of the layers is negligible and that the column is stable for a long period of time.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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