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  • Articles  (158,323)
  • 1965-1969  (110,176)
  • 1950-1954  (48,147)
  • Medicine  (158,323)
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  • Articles  (158,323)
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  • 1
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Zusammenfassung 3,5-Dijod-3′-chlor-4′-(p-chlorphenoxy) salicylanilid wird als ein neues Mittel gegen den Viehleberegel (Fasciola hepatica) beschrieben. In Schafen ergab eine Dosis von 5 mg/kg gegen geschlechtsreife Tiere und eine solche von 12,5 mg/kg gegen junge Leberegel eine hohe Wirksamkeit. Bei schwerem, akutem Leberegelbefall blieb sogar eine Dosis von 60 mg/kg ohne toxische Anzeichen. Ebenso wurde eine relativ hohe Wirksamkeit und eine gute Verträglichkeit bei der Behandlung von Leberegelinfektionen in Rindern festgestellt.
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  • 2
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    Cellular and molecular life sciences 25 (1969), S. 895-896 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary With the aid of the differential interference contrast microscope (systemNomarski), the pollen grains ofAlnus rugosa were examined. The characteristic surface structure, the ‘arci’ and certain structures in the vestibules of the pores are thus very clearly visible. A further use of this microscopic method may be possible for the investigation of pollen grains.
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  • 3
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    Human genetics 〈Berlin〉 8 (1969), S. 47-52 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The association pattern of the acrocentric chromosomes shows no significant difference between a population of mothers of mongoloid children and male and female controls of the same age-group. It could only be demonstrated that the associations of the mothers were interconnected by thread-like structures in a higher percentage. However, no significance could be deduced from for this phenomenon (P ≊ 0.1).
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  • 4
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    Human genetics 〈Berlin〉 8 (1969), S. 75-80 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Dünnschnitte von hypoton vorbehandelten Metaphase-Chromosomen des Menschen zeigen im Elektronenmikroskop unregelmäßig und vielfach gefaltete Fibrillen von ca. 200–250 Å Durchmesser. Nach Uranylacetatkontrastierung ist vorwiegend das Zentrum der Fibrillen dargestellt, während nach Phosphorwolframsäurebehandlung die Peripherie kontrastiert ist. Die Fibrillen erscheinen durch die hypotone Vorbehandlung wahrscheinlich verdickt. Als wahrscheinlichste Deutung der Bilder wird angenommen, daß eine Fibrille, die aus einem DNS-Doppelschraubenmolekül mit einem Histongerüst besteht, in viele kleine Falten und Schlingen gelegt, einen dickeren Strang, der einem chromatid entspricht, aufbaut. In der Metaphase ist dieser Strang noch zusätzlich in große Windungen gelegt.
    Notes: Summary Electron microscopy of sections of hypoton pretreated human metaphase chromosomes reveal irregular and multiple folded fibrils ca. 200–250 Å thick. After staining with uranyl acetate the central core of the fibrils is contrasted, whereas after treatment with phosphor tungsten acid the periphery is stained. The fibril appears to be thickened due to the hypotonic pretreatment. The most propable interpretation seems to be, that one fibril, made up of a DNA double helix and a histon-frame, is laid into many irregular minor foldings building up a strand corresponding to a chromatid. In metaphase this strand is laid into major coils.
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  • 5
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    Human genetics 〈Berlin〉 8 (1969), S. 86-93 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Chromosomal studies were carried out in bone marrow and testes of mice treated with lysergic acid diethylamide (LSD-25) in acute and chronic experiments, in blood cultures of rhesus monkeys (Macaca mulatta) treated with LSD-25 in vitro, and in blood cultures and testicular preparations of rhesus macaques treated with LSD. No increase in chromosomal damage was observed in bone marrow or testes, but all blood cultures treated with LSD in vitro and some of the blood cultures from rhesus macaques treated in vitro showed a significant increase in chromosomal breaks and rearrangements.
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  • 6
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    Human genetics 〈Berlin〉 8 (1969), S. 94-104 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei einem Patienten mit multiplen Mißbildungen wurde eine Duplikation für die distale Hälfte vom kurzen Arm des Chromosoms 2 und eine Defizienz an einem C-Chromosom gefunden. In der Literatur sind vier Fälle mit ähnlicher Duplikation, jedoch jeweils einer klein n Defizienz am Chromosom 3 beschrieben worden. Ein Vergleich der klinischen Merkmale bei den fünf Patienten zeigt weitgehende Übereinstimmungen. Es wird gefolgert, daß die gleichartige Duplikation für das einheitliche klinische Bild der Patienten verantwortlich ist. Es wurden Chromosomenmessungen, Analysen der Replikationsmuster und Meioseuntersuchungen durchgeführt. Die Genloci für das Ss- und das Rh-System konnten von einer Lokalisierung auf dem duplizierten Segment ausgeschlossen werden.
    Notes: Summary In a patient with multiple anomalies, a duplication comprising the distal half of the short arm of chromosome 2 and a small deficiency of a C-chromosome was found. Four other cases from the literature exhibit a similar duplication combined with a small deficiency each of chromosome 3. Comparison of the clinical pictures of the five patients revealed a conformity in the major features. It is concluded that the duplication is responsible for the uniform appearance of these patients. The studies performed include chromosome measurements, examination of replication patterns and meiosis. The gene loci for the Ss and Rh systems could be excluded from localization on the duplicated segment.
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  • 7
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    Human genetics 〈Berlin〉 8 (1969), S. 27-32 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In an attempt to follow up the persistence of single antigenic determinants of plasma proteins, the patterns of their determinants as revealed by cross-reactions with human plasma were tested in man, chimpanzee, the rhesus monkey, ox, sheep, pig, guinea pig and rat. The proteins investigated include ceruloplasmin, α1-lipoproteins, fibrinogen, plasminogen, βC-A- and β 1E-globulins. The results are presented in the form of pedigrees for the different plasma proteins: The phylogenetical pathways of the single determinants of human plasma proteins can be followed up; phylogenetically old determinants can be distinguished from others, which are possibly younger. The sensitivity of immunological techniques, which have been shown to be able to demonstrate single base changes in the DNA, for evolution research at the molecular level is stressed.
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  • 8
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    Human genetics 〈Berlin〉 8 (1969), S. 1-26 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary More than one hundred hemoglobin variants with single amino acid substitutions give information about point mutations in the DNA structure of the hemoglobin cistrons. Using the available data on the genetic code we concluded: 1. All single amino acid substitutions in human hemoglobin variants are compatible with the hypothesis that only one base is replaced in the DNA codon. 2. On the basis of this hypothesis, a number of possible condons in the \ga-, \gb-, \gg-, and \gd-chains can be excluded. This might be regarded as a first step towards a genetic sequence analysis of the hemoglobin cistrons. 3. Transitions as well as transversions are observed. However, the number of transitions is significantly higher than expected, if base replacement would be random. This result is not caused by the well known bias in ascertainment of human hemoglobins due to the fact that most variants are detected by a deviation in electrophoretic mobility. It is mainly, if not exclusively due to the cytosine—thymine transition in the DNA code. A prevalence of the same transition is also observed when amino acid differences between myoglobin and human α-, γ-, and β-chains are compared. Surprisingly, a corresponding increase in the frequency of the guanine—adenine transition was not observed. This seems to point to a relationship between mutating and coding strand within the DNA double helix. 4. As a side result of the comparisons between myoglobin, \ga-, \gg-, and \gb-chains, it turned out, that among the amino acid substitutions between myoglobin and the \ga-chain, those which are compatible and incompatible with a single base replacement within the DNA code are not distributed at random. There are too few (and too long) runs of incompatible substitutions. This could be due to partially incorrect amino acid pairing in the scheme proposed by Braunitzer. 5. Positions in \ga- and \gb-chains for which two, three, or more amino acid replacements were observed are not more frequent than expected, if distributions of replacement would be random. 6. There is no clustering of detected mutations in adjacent codons.
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  • 9
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    Human genetics 〈Berlin〉 8 (1969), S. 39-46 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Unter Anwendung verfeinerter Trennverfahren wurde das β-Lp(a+)-Lipoprotein des menschlichen Serums in immunologisch und elektrophoretisch reiner Form dargestellt. Es wurde hinsichtlich seiner Lipidzusammensetzung analysiert und mit ebenfalls immunologisch und elektrophoretisch rein erhaltenen β-Lp(a-)- und α1-Lipoproteinen verglichen.
    Notes: Summary Through application of refined separation techniques the β-Lp(a+)-lipoprotein of human serum was characterized in an immunologically and electrophoretically pure form. It was analyzed with regard to its lipid-composition and compared to likewise electrophoretically and immunologically pure β-Lp(a-)- and α1-lipoproteins.
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  • 10
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    Human genetics 〈Berlin〉 8 (1969), S. 33-38 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a family, two children exhibited chromosome aberrations: a male infant had trisomy G1 and his sister Bp deficiency (cri du chat-syndrome). Screening for proteinpolymorphisms within three generations revealed heterozygosity for two enzyme variants, LDH BB' and 6-PGD AB, in a number of family members, some of whom were double heterozygotes. Linkage can not be tested since these variants are derived from different sibships. An aunt of the affected children exhibited a LDH isoenzyme pattern as it is to be expected in a protein chimaera. In addition, a high number of aneuploid and polyploid cells, including endomitoses, were present in the blood of this proband, and similarly in her mother. The origin of the chimaera is discussed.
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  • 11
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    Human genetics 〈Berlin〉 8 (1969), S. 81-85 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Male C3H inbred mice and male (101xC3H) F1 hybrids were treated with various caffeine doses over a long period. After the end of treatment the animals were dissected and the metaphase I figures of the cycle of spermatogenesis were analysed. The experiments revealed no distinct evidence for the induction of chromosomal aberrations in the cycle of spermatogenesis caused by caffeine up to metaphase I.
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  • 12
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    Human genetics 〈Berlin〉 8 (1969), S. 111-114 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Simultaneous occurrence of the trisomy G and of any other autosomal aberration is rare. The authors detected familial balanced translocation t(3p-; 17q+) in three members of a family. One child possessed this translocation and moreover trisomy G. It does not seem that there might be any relationship between the occurrence of the translocation and the aneuploidy.
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  • 13
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    Human genetics 〈Berlin〉 8 (1969), S. 105-110 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Messungen der B-Chromosomen wurden in Metaphasen verschiedener Probanden durchgeführt: 1. drei Patienten mit Verdacht auf Cri du Chat-Syndrom ohne sichtbare Defizienz am kurzen Arm von Chromosom 5; 2. vier Patienten mit deutlich erkennbarer Defizienz; 3. drei gesunde Vergleichspersonen mit unauffälligem Karyotyp. Eine Deletion war in keinem der Verdachtsfälle nachweisbar. In der Gruppe mit Defizienz zeigte sich eine erhebliche Variation im Ausmaß des deletierten Segments. In Ergänzung zu Methoden der Chromosomenmessung anderer Autoren (vgl. Warburton et al., 1967, 1969; Miller et al., 1969) wird eine weitere einfache Methode angewendet, die unter geringem Aufwand in Zweifelsfällen Aufschluß über das Vorhandensein und Ausmaß einer Deletion am kurzen Arm eines B-Chromosoms geben kann.
    Notes: Summary Measurement studies were carried out on the B-group chromosomes in three patients with suspected cri-du-chat syndrome, four karyotypically confirmed cases of the syndrome and three normal subjects. None of the propositi showed a detectable short-arm deletion. Within the four cases with obvious short arm deletion the amount of the deletion varies to a high degree. In addition to the technique of chromosome measurement proposed by other authors (e.g. Warburton et al., 1967, 1969; Miller et al., 1969), we present another method easely to apply for screening purposes in cases in which a deletion is not readily detectable, blind studies were unsuccessful, or when the amount of the deletion ought to be demonstrated.
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  • 14
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    Human genetics 〈Berlin〉 8 (1969), S. 115-133 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei 148 weiblichen Verwandten von 33 Patienten mit Duchennescher Muskeldystrophie in 21 Sippen sowie bei 25 Kontrollpersonen ist die Kreatin-Phosphokinase bestimmt worden. Die Getesteten befanden sich im Alter zwischen 6 Monaten und 79 Jahren. Erhöhte CPK-Werte fanden wir bei 7 (88%) von 8 sicheren und wahrscheinlichen Genträgerinnen. Von den 30 möglichen Konduktorinnen der Gruppe A — bei denen das statistische Risiko der Heterozygotie bekannt ist — wiesen 17 (52%) über die Norm erhöhte CPK-Werte auf. Die Zahl der als Heterozygote identifizierten Personen entsprach der statistischen Erwartung von 13. Von den 14 Müttern isoliert erkrankter Patienten wurden bei 10 (71,5%) erhöhte CPK-Aktivitäten nachgewiesen. In der Gruppe B der möglichen Trägerinnen, bei denen das statistische Risiko, heterozygot zu sein, nicht bekannt ist, konnten bei insgesamt 110 weiblichen Verwandten bei 32 Personen (29%) erhöhte CPK-Aktivitäten gemessen werden. In den 4 Sippen der genetisch sicheren Konduktorinnen können wir auf Grund unserer Befunde nicht bestimmen, zu welchem Zeitpunkt die Neumutation auftrat. Das gleiche gilt für weitere 9 Sippen, während bei den restlichen 8 der Mutationszeitpunkt diskutiert wird. Die CPK-Bestimmung zur Identifizierung von Heterozygoten hat sich als bester Indicator erwiesen. Die ca. 25% falsch-negativen Werte sind durch Mehrfachbestimmungen zu mindern. Mögliche Ursachen der falsch-negativen Werte sind intraindividuelle Schwankungen, meßtechnische Fehler und die Mosaikstruktur heterozygoter Gene gemäß der Lyon-Hypothese.
    Notes: Summary Serum creatine-phosphokinase activity has been investigated in 148 female relatives of 33 patients with progressive muscular dystrophy (type Duchenne) and in 25 controls. The age of the relatives ranged from 6 months to 79 years. Elevated creatine kinase activity was found in 7 (88%) of 8 definite and probable carriers. Among 30 possible carriers in whom the risk of heterozygosity could be calculated, 17 subjects were identified as carriers, in close agreement with the expectation of 13. — Among 110 other possible carriers, in whom the risk of heterozygosity could not be determined, 32 carriers were identified. Of the 14 mothers of sporadic cases, included in this group, high CK activity was found in 10. — In the 4 families of the definite carriers it was not possible to determine at which time the new mutation took place. In 8 families of possible carriers data supporting the appearance of the mutation in some subjects are discussed. — For genetic prognosis, an elevated CK value in a relative of a Duchenne patient is regarded as reliable evidence of heterozygosity, but if the CK value is within the normal range there is an appreciable risk that it is a “false negative” and that the subject is actually a carrier. Possible causes of “false negative” observations are technical difficulties, decline of CK levels with increasing age, heterozygote variability consequent to lyonization of an X-chromosome, and genetic heterogeneity.
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  • 15
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    Human genetics 〈Berlin〉 8 (1969), S. 142-157 
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Bloom-Syndrom gehört mit der Fanconi-Anämie und der Ataxia-Telangiektasia Louis-Bar zu einer Gruppe von Anomalien, die als gemeinsame Kennzeichen eine autosomal-recessive Vererbung, gehäufte spontane strukturelle Chromosomenaberrationen und ein erhöhtes Risiko für die Entstehung maligner Neoplasien haben. Bei 2 eigenen Patienten fanden wir gehäufte strukturelle Chromosomenanomalien—Brüche, Fragmente und Translokationsfiguren—in kultivierten Lymphocyten, während Fibroblastenuntersuchungen wegen nur mangelhafter Proliferation der Kulturen mißlangen. Entsprechende Chromosomenaberrationen konnten gehäuft auch in Lymphocyten und Fibroblasten vom Vater des Jungen, nicht aber bei beiden Müttern nachgewiesen werden. Der Patient hat einen Immunglobulinmangel in den drei Fraktionen γa, γg und γm, das Mädchen nur ein γa-Defizit. Die Immunglobuline des Vaters und der Mütter sind normal. Auf PHA reagieren die Lymphocyten der Patienten und der untersuchten Eltern mit normaler Transformations-und Proliferationsrate, wenn auch die Mehrzahl der Kulturen des Jungen und mehrere Kulturen seiner Eltern—vielleicht infolge größerer Empfindlichkeit gegen exogene Störfaktoren—mißlangen.
    Notes: Summary Autosomal recessive inheritance, increased incidence of structural chromosomal anomalies, and high risk for malignancies are common features of Bloom's syndrome, Fanconi's anemia, and Louis-Bar's ataxia-telangiectasia. A high fequency of structural chromosomal aberrations—breaks, fragments, and translocation figures—was found in lymphocytes of 2 patients with Bloom's syndrome whereas studies on fibroblasts could not be done because of poor proliferation. An increased rate of chromosome aberrations was also seen in lymphocytes and fibroblasts of the boy's father but not in the cells of both mothers. γa, γg, and γm were deficient in the boy. The girl had only a γa deficiency, and the parents' immunoglobulins were normal. The lymphocytes of both patients and parents responded normally to PHA, but several cultures of the boy's parents and 5 out of 7 cultures from the boy failed to respond, maybe because of pronounced susceptibility to exogenous disturbance.
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  • 16
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'étude de différents allotypes du système Gm a été pratiquée sur les sérums provenant de onze familles dont au moins un des membres présentait un déficit mineur ou grave portant sur une ou plusieurs classes d'immunoglobulines. Dans six de ces familles, deux ordres de faits sont observés, simultanément ou non, chez des sujets ne présentant, par les méthodes classiques, aucun désordre immunologique: une diminution de l'expression phénotypique d'un ou plusieurs facteurs qui permet de conclure à un déficit sélectif de certaines sous-classes de γG; ces déficits sont, parfois, transmis directement à la génération suivante; des anomalies d'ordre qualitatif se caractérisant par la présence de phénotypes, en règle générale, rarement rencontrés parmi des Caucasiens. L'hypothèse faisant appel à l'existence de gènes de structure rares ou anormaux pour expliquer ces faits ne peut être retenue car elle aboutit à la constatation de trop nombreuses exclusions de paternité ou de maternité. Dans une seconde hypothèse, nous supposons qu'existent des gènes de régulation responsables de la synthèse des chaines γ1, γ2 et γ3 et que les anomalies phénotypiques observées sont l'expression de la modification de ces gènes. La transmission de ces gènes de régulation se ferait indépendamment de celle des gènes de structure.
    Notes: Summary Different allotypes of the Gm system were studied on sera from eleven families where at least one of the members had a minor or important deficiency in one or several classes of immunoglobulins. In six of these families two facts were observed, simultaneously or not, in subjects showing no immunologic disorder, as revealed by conventional methods: a reduction in the phenotypic expression of one or several factors which allowed to conclude that there is a selective deficiency in certain γG subclasses; these deficiencies are sometimes directly transmitted to the following generation; qualitative anomalies characterized by the presence of phenotypes, as a general rule, rarely encountered among Caucasians. The hypothesis based on the existence of rare or abnormal structural genes could not be applied to explain these facts because it would have led to the statement that there are too many exclusions of paternity or maternity. In a second hypothesis, we supposed that there exist regulator genes, responsible for the synthesis of the γ1, γ2, and γ3 chains, and that the observed phenotypic anomalies are an expression of the mutation of these genes. The transmission of these regulator genes could be independent of that of the structural genes.
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  • 17
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    Human genetics 〈Berlin〉 8 (1969), S. 62-63 
    ISSN: 1432-1203
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  • 18
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    Human genetics 〈Berlin〉 8 (1969), S. 64-66 
    ISSN: 1432-1203
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    Notes: Summary Blood samples from 515 unrelated individuals and from 41 families with 80 children living in Hessen (Germany) were examined for erythrocyte phosphoglucomutase (PGM1) polymorphism. The gene frequences especially fit well with those obtained in Berlin and Danmark. The family studies verify the supposed way of heredity without any exception.
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  • 19
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    Human genetics 〈Berlin〉 8 (1969), S. 53-61 
    ISSN: 1432-1203
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    Description / Table of Contents: Zusammenfassung In den Gruppen der Kinder mit Down-Syndrom (23), deren Eltern (9), der Kinder mit Turner-Syndrom (5) und behandelter Hypothyreose (9) wurden im Vergleich zu Kontrollen (25) erhöhte Satellitenassoziationswerte gefunden. Daß die Gruppe der Kinder mit Down-Syndrom und einige von deren Eltern vermehrt Assoziationen aufweisen, könnte mit einer mit erhöhter Satellitenassoziation einhergehenden Tendenz zu Chromosomenanomalien in Zusammenhang stehen. Die erhöhten Werte bei den behandelten Hypothyreosen könnten mit der Wirkung des Thyroxins erklärt werden.
    Notes: Summary As compared with controls (25) an increased frequency of satellite association was observed in groups of mongoloid children (23), their parents (9) and in cases of Turner's syndrom (5) and treated hypothyreosis (9). The high incidence of associations in the group of mongoloids and in some of their parents may be explained with a possible simultaneous tendency to satellite association and nondisjunction. The high values in treated hypothyreosis could be the consequence of thyroxin action.
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  • 20
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    Human genetics 〈Berlin〉 8 (1969), S. 67-68 
    ISSN: 1432-1203
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    Notes: Summary The polymorphism of PGM1 has been investigated in a series of 366 families from Southwestern Germany with 676 children. The segregation of the children's phenotypes is in agreement with the formal genetic model.
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  • 21
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    Human genetics 〈Berlin〉 8 (1969), S. 71-74 
    ISSN: 1432-1203
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    Notes: Summary Two cases of the cri-du-chat-syndrome are described, one with mosaicism in regard to the deletion, the other with probable differences of the size of the deletion. In both cases there have been found a few cells, where the distal part of the short arm of a B-chromosome has been satellited.
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  • 22
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    Human genetics 〈Berlin〉 8 (1969), S. 69-70 
    ISSN: 1432-1203
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    Notes: Summary The 6-PGD-polymorphism has been investigated in a series of 220 families from Southwestern Germany comprising 546 children. The formal hypothesis “two autosomal loci 6-PGDA and 6-PGDB, two alleles 6-PGDB b and 6-PGDB b1 at the locus 6-PGDB” covers the results.
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  • 23
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    Human genetics 〈Berlin〉 8 (1969), S. 165-172 
    ISSN: 1432-1203
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    Notes: Summary The HL-A transplantation system is described in a survey. The nomenclature used by some investigators is compared. Two families serve as example for inheritance. The family data available concerning HL-A 2 are described. The importance of the HL-A antigens for grafts is shown, and a comparison with the mixed leucocyte culture is made.
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  • 24
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    Human genetics 〈Berlin〉 8 (1969), S. 173-177 
    ISSN: 1432-1203
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    Notes: Summary If by serological methods of tissue typing one antigen only is detected in one or both of the loci LA and 4 of the histocompatibility system HL-A, the question arises whether it is homozygous or heterozygous. The probability thereof is calculated. It depends on the frequency of the known and unknown genes in the HL-A-system. If e.g. the HL-A type of an examinee is 1,3,8 this subject could be homozygous 1,3,8,8 or heterozygous (with an unknown antigen X) 1,3,8,X. The frequencies of homozygous and heterozygous individuals are calculated in all possible combinations of the LA and 4 loci. The results justify always for both the LA-and 4 locus the assumption of heterozygosity, with the one exception that the gene HL-A 2 is under consideration. There the calculations result in a value of 49% for homozygosity (2,2) and 51% for heterozygosity (2,X). Neither alternative is in this case essentially more probable. For transplantations generally heterozygosity can be assumed — with the exception of HL-A 2 — and therefore the minor grade of histocompatibility.
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    Human genetics 〈Berlin〉 8 (1969), S. 178-182 
    ISSN: 1432-1203
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    Notes: Summary In swine, the enzyme sorbitol dehydrogenase exhibits a genetically determined polymorphism as identified by multiple electrophoretic bands suggesting a tetrameric structure (Op't Hof, 1969). In order to obtain further information on the genetics of this polymorphism, a number of other vertebrate species were examined. Multiple alleles at the SDH gene locus were found in the Cyprinid fishes Leuciscus and Rutilus, and in the Salmonid fish Salmo trutta. The electrophoretic patterns found in these species are compatible with the model of a tetrameric structure of the enzyme. This model was further verified by dissociation-reassociation studies with the homomeric enzymes of swine and Leuciscus. Since in the heterozygote an intensity gradient of the isozymes was seen, the three phenotypes observed in swine were further characterized by means of activity measurements and application of different substrates. The results point to a differential activity of the two different homomeres.
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    Human genetics 〈Berlin〉 8 (1969), S. 134-136 
    ISSN: 1432-1203
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    Description / Table of Contents: Zusammenfassung Die Verfasser berichten über Phänotypen-und Gen-Frequenzen des Coeruloplasmin-Polymorphismus. In allen untersuchten Populationen (Deutsche, Isländer, Iraner, Pakistani und Koreaner) konnten sehr hohe Frequenzen des Allels CpB beobachtet werden (0,978–0,996), während die Frequenzen der Allele CpA (0,003–0,013) und CpC (0,000–0,013) deutlich geringer sind.
    Notes: Summary Phenotype and gene frequencies of the ceruloplasmin polymorphism are reported. In all populations considered here (Germans, Icelanders, Iranians, Pakistani, and Koreans) high frequencies of the allele CpB (0.978–0.996) could be observed, whilst the frequencies of the alleles CpA (0.003–0.013) and CpC (0.000–0.013) are very low.
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    Human genetics 〈Berlin〉 8 (1969), S. 137-141 
    ISSN: 1432-1203
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    Description / Table of Contents: Zusammenfassung Kanarienvogel (Serinus) und Stieglitz (Carduelis) zeigen für das Enzym Glucose-6-Phosphat-Dehydrogenase in der Stärkegelektrophorese jeweils nur eine Bande, die aber verschiedene Positionen einnehmen. Interspecieshybriden beider Geschlechter wurden aus der natürlichen Kreuzung Kanarienvogel (f)xStieglitz (m) erhalten; die Identifizierung des Geschlechts der äußerlich ähnlichen Hybriden erfolgte durch Chromosomenanalyse. Die Hybriden zeigen in beiden Geschlechtern ein identisches Elektrophoresemuster, das die gleiche Zone umfaßt wie bei dem in vitro-Gemisch aus Gewebehomogenaten der Ausgangsarten. Entsprechende Befunde liefert die Analyse der 6-Phosphogluconatdehydrogenase. Hieraus ist zu schließen, daß beide Enzyme von autosomalen Genen determiniert werden.
    Notes: Summary The electrophoretic mobility of the single G-6-PD-band in Serinus and Carduelis is different. The natural cross Serinus (f)xCarduelis (m) results in viable hybrids of both sexes, as confirmed by chromosome analysis. The isoenzymes of G-6-PD are indentical in both sexes of the hybrids, exhibiting a broad diffuse pattern comprising the same zone as obtained from an in vitro mixture of parental homogenates. Related findings are reported on the enzyme 6-PGD. It is concluded that both enzymes are autosomally determined in these species.
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    Notes: Summary The frequency of pseudocholinesterase variants controlled by the E1- and E2-locus have been determined in serum samples from Germany, Čzechoslovakia, Finland and from Laps.
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    Human genetics 〈Berlin〉 8 (1969), S. 162-164 
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    Notes: Summary Sera of 1,000 blood donors were tested for various combinations of salivary and pancreatic amylase isoenzymes and the frequency of their occurrence was determined in the series mentioned. Five combinations of isoamylases were found. A combination of 1 salivary and 1 pancreatic amylase was found most frequently (89.5%), the frequency of the other four combinations was relatively low (0.2–5.1%). Hereditary character of amylase isoenzymes was confirmed in a series of 36 families.
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    Description / Table of Contents: Zusammenfassung 1. Die Merkmale der Finger- und Handleisten von je 100 männlichen und weiblichen Mongoloiden und je 100 männlichen und weiblichen Normalen wurden untersucht. 2. Mittels einer Diskriminanzanalyse wurden sieben Merkmale ermittelt, auf Grund derer es an unserem Material möglich ist, ein Individuum eindeutig der Gruppe der Normalen oder der Gruppe der Mongoloiden zuzuordnen. 3. Die Diskriminanzanalyse ergab als wichtigste Hand- und Fingerleistenmerkmale zur Unterscheidung der Normalen von den Mongoloiden: Größe des atd-Winkels auf der Handfläche, Vorhandensein oder Fehlen eines Musters im III. Interdigitalraum, Vorhandensein oder Fehlen einer Ulnarschleife auf dem 2. Finger, Vorhandensein oder Fehlen einer Vierfingerfurche.
    Notes: Summary 1. The characteristics of hand- and fingerprints of normal and mongoloid individuals, 100 of either sex, were studied. 2. Using a discriminant analysis, seven dermatoglyphic characteristics were determined, which, if combined, permitted to assign each individual of our series to either the group of mongoloids or the group of normals. 3. Discriminant analysis revealed the following dermatoglyphic characters as the most important to distinguish normal from mongoloid individuals: size of atd-angle on palm, occurrence or absence of pattern in third interdigital space, occurrence or absence of ulnar loops on second finger, occurrence or absence of a four-finger fold.
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    Calcified tissue international 3 (1969), S. 198-210 
    ISSN: 1432-0827
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    Calcified tissue international 3 (1969), S. 84-92 
    ISSN: 1432-0827
    Keywords: Nacre ; Pallial fluid ; Crystal growth
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    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une étude au microscope électronique est réalisée au cours de la croissance des coquilles de nacre de plusieurs espèces de mollusques marins. Des études de coupes de coquille périphérique montre que la première étape de la formation cristalline consiste en une „polymérisation” d'une partie du liquide pallial, formant ainsi des lamelles parallèles à la surface épithéliale. Ces lamelles forment des compartiments renfermant un liquide pallial modifié. Le début de formation des cristaux s'effectue dans ces compartiments en contact avec un cristal occupant une couche adjacente. Pendant la croissance cristalline, la matrice organique, présente dans le compartiment, est déplacée par la surface de cristal, en voie de croissance. Lorsque cette derniére est achevée, le cristal est entièrement entouré par une fine enveloppe organique. Cette étude démontre que le liquide pallial et ses constituants organiques sont responsables de la formation d'une matrice ou d'un support pour la croissance cristalline. Il s'agit d'un système de régulation pour une croissance ordonnée, régissant l'orientation des cristaux et pouvant, en outre, induire une formation de nouveaux cristaux. Les compartiments, qui se forment pendant la croissance de la coquille, sont responsables de l'épaisseur uniforme, de l'orientation préférentielle et de la minéralogie des cristaux, ainsi, que d'autres éléments caractéristiques de la nacre adulte.
    Abstract: Zusammenfassung Es wurde eine Studie am Elektronenmikroskop über das Wachstum der Perlmuttmuschel bei verschiedenen Arten von Meer-Molusken durchgeführt. Untersuchungen von Schnitten der präparierten Muschelhülle zeigten, daß der erste Schritt bei der Kristallbildung in einer „Polymerisation” eines Teiles der Pallialfüssigkeit besteht, wobei parallel zur Oberfläche des Epithels Lamellen gebildet werden. Diese Lamellen bilden Kompartimente, welche eine modifizierte Pallialflüssigkeit enthalten. Die Kristallbildung wird in diesen Kompartimenten durch den Kontakt mit einem Kristall in einer angrenzenden Schicht angeregt. Während des Kristallwachstums wird die organische Matrix, welche in den Kompartimenten vorliegt, durch die wachsende Oberfläche des Kristalls ersetzt. Nach Abschluß des Wachstums ist der Kristall vollständig von einer feinen organischen Hülle umgeben. Diese Untersuchungen zeigen, daß die Pallialflüssigkeit mit ihren organischen Komponenten imstande ist, eine Matrix oder ein Substrat zur Bildung und zum Wachstum des Kristalles zu beschaffen. Sie dient als regulierende Vorrichtung zur Steuerung des regelmäßigen Wachstums und der Kristallanordnung, und sie kann sich zudem bei der Induktion neuer Kristalle beteiligen. Die Bildung von Kompartimenten während des Muschelwachstums ist für die gleichmäßige Dicke, die bevorzugte Orientierung und die Mineralogie des Kristalls verantwortlich, sowie für andere Merkmale, welche reifes Perlmutt aufweist.
    Notes: Abstract An electron-microscopic study was made of nacreous shell growth in several species of marine molluscs. Studies of sections of mantle-shell preparations show that the first step in crystal formation is the “polymerization” of part of the pallial fluid to form lamellae parallel to the surface of the epithelium. These lamellae form compartments enclosing a modified apallial fluid. Initiation of crystals occurs in these compartments in contact with a crystal in an adjacent layer. During crystal growth the organic matrix present in the compartment is displaced by the growing surface of the crystal. When growth is complete the crystal is entirely enveloped by a delicate organic sheath. These studies show that the pallial fluid with its organic constituents is responsible for supplying a matrix or substrate for crystal initiation and growth. It serves as a regulatory device for guiding the orderly growth and arrangement of crystals and, further, it may participate in the induction of new crystals. The formation of compartments during shell growth accounts for the uniform thickness, preferred exhibited orientation and mineralogy of the crystals as well as other features exhibited by the mature nacre.
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    Calcified tissue international 3 (1969), S. 142-150 
    ISSN: 1432-0827
    Keywords: Calcium Distribution ; Tetracycline ; Bone Formation ; Chick
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    Description / Table of Contents: Résumé La présence de calcium (technique GBHA) dans les cellules du périoste: ostéoblastes, ostéocytes et chondrocytes d'os en cours de développement chez l'embryon de poulet, confirme les résultats deKashiwa (1966) chez le rat. La modification du développement osseux par l'administration de tétracycline indique qu'il y a une corrélation directe entre la quantité de calcium à l'intérieur de ces cellules et le degré de minéralisation des matrices adjacentes. Le calcium du front de calcification de l'os et de la matrice du cartilage anormalement calcifiée qui résulte du traitement à la tétracycline ne semble pas avoir la même capacité à entrer en chélation sous l'action du GBHA, que le calcium d'os plus âgé et de matrice normalement calcifiée. La distribution du matériel positif au GBHA semble correspondre à celle d'un lipide lié, résistant à la pyridine, et déjà décrit.
    Abstract: Zusammenfassung Das Vorkommen von Calcium (GBHA-Technik) in den Zellen des Periosts, in den Osteoblasten, Osteocyten und Chondrocyten des sich entwickelnden Knochens im Hühnerembryo bestätigt die Resultate, welcheKashiwa (1966) bei der Ratte beschrieb. Eine durch Tetracyclingaben hervorgerufene Veränderung der Knochenentwicklung zeigt, daß eine direkte Korrelation zwischen dem Calciumgehalt in diesen Zellen und dem Mineralisationsgrad der sie umgebenden Matrices besteht. Das Calcium an der Calcificationsgrenze des Knochens und in der durch Tetracyclinbehandlung abnormal verkalkten Knochenmatrix scheint sich dadurch zu unterscheiden von älteren Knochen und von normal verkalkender Knorpelmatrix, daß es mit GBHA ein chelat zu bilden vermag. Die Verteilung von GBHA-positivem Material scheint mit der eines früher beschriebenen pyridinresistenten gebundenen Lipids übereinzustimmen.
    Notes: Abstract The presence of calcium (GBHA technique) in the periosteal cells, osteoblasts, osteocytes and chondrocytes of developing chick embryo bone confirms the findings ofKashiwa (1966) in the rat. Modification of bone development by tetracycline administration indicates that there is a direct correlation between the amount of calcium within these cells and the degree of mineralization of the adjacent matrices. The calcium of the calcification front of bone and the abnormally calcified cartilage matrix resulting from tetracycline treatment appears to differ from that of the older bone and normally calcifying cartilage matrix in its ability to chelate with GBHA. The distribution of the GBHA positive material appears to correspond to that of a pyridine-resistant bound lipid previously reported.
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    Calcified tissue international 3 (1969), S. 211-237 
    ISSN: 1432-0827
    Keywords: Bone formation ; Tetracycline labeling
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    Calcified tissue international 3 (1969), S. 261-265 
    ISSN: 1432-0827
    Keywords: Bone crystals ; Exchange ; Sodium ; Kinetics
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    Description / Table of Contents: Résumé Bien que des études antérieures aient démontré qu'une partie du sodium squelettique est incorporée dans la maille cristalline et n'est pas échangeable, la situation du sodium mobile demande à être clarifiée. Une étude cinétique utilisant un système in vitro (cristaux d'hydroxyapatite) a été entreprise. Ce n'est que dans des conditions très particulières que des zones d'attachement superficiel à la maille cristalline ont pu être mises en évidence. Les échanges sont presque instantanés dans des conditions physiologiques: 99% de l'équilibre final est atteint en deux minutes ou moins. Un tel échange rapide ne peut s'expliquer que par une réaction aqueuse. Le sodium superficiel est, par conséquent, situé dans les couches d'hydratation des cristaux individuels. La quantité de sodium, associée à la surface cristalline, est donc pratiquement insignifiante.
    Abstract: Zusammenfassung Während durch frühere Studien anhand der Literatur festgelegt werden konnte, daß ein Teil des im Skelett vorhandenen Natriums in intrakristallinen Gitterstellungen liegt und nicht austauschbar ist, blieben einige Fragen hinsichtlich der Lokalisation des rasch austauschbaren Natriums offen. Es wurde eine kinetische Untersuchung in vitro mittels eines Modellsystems (Hydroxyapatitkristalle) durchgeführt. Nur unter speziellen Bedingungen konnten die an die Gitteroberfläche gebundenen Stellungen nachgewiesen werden. Unter physiologischen Bedingungen fand der Austauch beinahe augenblicklich statt: 99% des Endequilibriums wurde in 2 min oder weniger erreicht. Ein so schneller Austausch ist nur unter Annahme einer Reaktion in wäßriger Phase denkbar. Das oberflächlich liegende Natrium ist demzufolge in der Hydratationsschicht der individuellen Kristalle vorhanden. Die an die Kristalloberfläche selbst gebundene Natriummenge ist für praktische Zwecke unwesentlich.
    Notes: Abstract While earlier studies in the literature have established that some skeletal sodium resides in intracrystalline lattice positions and is non-exchangeable, some questions remained as to the location of that sodium which is readily exchanged. A kinetic study was made of a model system (hydroxyapatite crystals)in vitro. Only under special conditions could lattice-bound surface sites be demonstrated. Under physiological conditions, the exchange was nearly instantaneous; 99% of the final equilibrium was attained in two minutes or less. Such a rapid exchange is consistent only with an aqueous reaction. The surface sodium is, therefore, present in the hydration layers of the individual crystals. The amount of sodium associated with the crystal surface itself is, for practical purposes, insignificant.
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    Calcified tissue international 3 (1969), S. 293-307 
    ISSN: 1432-0827
    Keywords: Apatites ; Crystals ; X-ray diffraction ; Structure
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    Calcified tissue international 3 (1969), S. 308-317 
    ISSN: 1432-0827
    Keywords: Bone ; Enamel ; Hydroxyapatite ; X-ray Diffraction
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    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'objet de cette étude a été de déterminer l'effet du mode de préparation (par meulage) sur la largeur des raies de diffraction de l'émail. La préparation d'émail, par meulage, en utilisant divers procédés ainsi qu'une pièce à main dentaire conventionnelle provoque un élargissement des pics obtenus (002, 211, 200 et 202) lorsqu'on la compare avec de la poudre d'émail, obtenue par meulage à l'aide de billes. L'élargissement des raies n'est pas observé lorqu'un monocristal d'hydroxylapatite est meulé à l'aide d'un diamant fin. En général, l'élargissement est moins important, lorsque le meulage est effectué à l'aide de turbines dentaires. L'importance du meulage dépend de façon variable d'un ou plusieurs des facteurs suivants: rugosité des instruments coupants, vitesse de meulage, direction de meulage, et la présence ou l'absence d'eau. Le meulage prolongé par billes de l'émail provoque aussi un élargissement dans les mêmes conditions, cependant, l'os n'est pas endommagé. Ces résultats indiquent que l'émail est plus sensible que l'hydroxylapatite et l'os. L'élargissement de raies peut être dû soit à une déformation de la maille cristalline, soit à une diminution de taille des cristaux.
    Abstract: Zusammenfassung Es wurde eine Untersuchung durchgeführt, um den Einfluß der Probenvorbereitung (Zerreibungsmethode) auf die Breite des Linienprofil-Querschnittes von Zahnschmelz zu bestimmen. Gewinnung von Zahnschmelz mit den verschiedenen Schneidinstrumenten einer konventionellen Bohrmaschine verursachte eine Verbreiterung aller untersuchten Peaks (002, 211, 200 und 202) im Vergleich zum gleichen Schmelz, der mit dem Rosenbohrer zerrieben wurde. Eine Verbreiterung der Linie konnte nicht beobachtet werden, wenn ein einzelner Kristall von Hydroxyapatit mit einem ganz feinen Diamanten zerrieben wurde. Im allgemeinen war die Verbreiterung weniger ausgesprochen, wenn die hochtourige Bohrtechnik zur Anwendung kam. Das Ausmaß der Verbreiterung, das durch Zahnbohrer verursacht wurde, war abhängig von einem oder mehreren der folgenden Faktoren: Rauheit des Schneidinstrumentes, Zerreibungsgeschwindigkeit, Zerreibungsrichtung und das Vorhandensein oder Fehlen von Wasser. Verlängerte Zerreibung von Schmelz mit dem Rosenbohrer verursachte ebenfalls eine Verbreiterung. Unter identischen Bedingungen blieb der ausgeglühte Knochen jedoch unversehrt. Diese Beobachtungen zeigen, daß Schmelz für Zerreibungsschäden anfälliger ist, als Hydroxyapatitkristalle oder ausgeglühter Knochen. Die eigentliche Ursache der Linienverbreiterung kann entweder eine Schädigung infolge Distortion des Gitters oder eino Reduktion der Größe der individuellen Kristalle sein.
    Notes: Abstract A study was conducted to determine the effect of sample preparation (grinding method) upon breadth of the diffraction profile of enamel. Collecting enamel by grinding with various cuttin tools in the low-speed dental handpiece caused broadening of all peaks (002, 211, 300 and 202) examined, compared to ball, ground, counter-part enamel. Line broadening was not observed when a single crystal of mineral hydroxyapatite was ground with a very fine diamond. In general, broadening was less pronounced with the high-speed air turbine technique. The amount of broadening caused by dental burs depended upon one or more of the following factors: coarseness of cutting instrument, grinding speed, grinding direction, and the presence or absence of water. Prolonged ball grinding of enamel also caused broadening; under identical conditions, however, annealed bone remained undamaged. These findings indicate that enamel is more sensitive to grinding damage than the mineral hydroxyapatite crystal or annealed bone. The actual cause of line broadening may be either strain due to lattice distortions or a reduction in size of individual crystallites.
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    Calcified tissue international 3 (1969), S. 348-357 
    ISSN: 1432-0827
    Keywords: Inhibitors ; Nucleation ; Apatite ; Collagen
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    Description / Table of Contents: Résumé Des ions de Mg, Sr et F sont inhibitoires pour la formation de l'apatite quand on les ajoute à un tampon de calcification, séparément ou en combinaisons. La précipitation de l'apatite causée par des cristaux d'apatite est moins sensible à l'action inhibitrice que la nucléation spontanée et que la précipitation catalysée par la collagène d'os de mouton. La précipitation spontanée ou catalysée sont approximativement aussi sensibles. L'inhibition par des combinaisons de Mg avec des ions de Sr ou de F est additive. Ces résultats montrent que ces inhibiteurs ont acucune action spécifique sur la catalysation par la collagène de l'os de mouton qui soit différente de celle sur la nucléation de l'apatite en soi.
    Abstract: Zusammenfassung Mg, Sr und F Ionen hemmten die Fällung von Apatit wenn sie zu einem Calciumphosphatpuffer einzeln oder zusammen hinzugefügt wurden. Die Fällung von Apatit durch Apatitkeime war weniger empfindlich hinsichtlich der Hemmung als die spontane Nucleation und als die Fällung von Apatit, welche von Schafsknochenkollagen katalysiert werden kann. Die spontane und katalysierte Fällung sind ungefähr gleich empfindlich. Die Hemmung von Mg in Kombination mit Sr oder F Ionen war additiv. Diese Resultate weisen darauf hin, daß keine spezifischen Effekte bei der Katalyse von Knochenkollagen vorliegen, welche von den Effekten bei der Nucleation von Apatit an sich verschieden sind.
    Notes: Abstract Mg, Sr and F ions acted as inhibitors of apatite formation when added to a calcification buffer separately or in combinations. The precipitation of apatite under the influence of apatite seeds was less susceptible to inhibition than were spontaneous nucleation and apatite formation catalyzed by sheep bone collagen, while the latter two were about equally susceptible. Combinations of Mg with Sr or F ions showed additive effects. These results suggest that no specific effects of these inhibitors occurred on the catalytic action of the bone collagen different from their effects on the nucleation of apatite as such.
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    Calcified tissue international 3 (1969), S. 30-37 
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    Description / Table of Contents: Résumé La parathyroïdectomie des poussins et l'administration de parathormone chez des poussins parathyroïdectomisés ont provoqué des changements de la composition du cartilage épiphysaire dans les 24 heurs qui suivent le traitement. Ces changements peuvent se résumer de la façon suivante: 1. La parathyroïdectomie augments la teneur des éléments collagènes et diminue celle du calcium alors que la tenuer des hexosamines et des cendres rest la même que dans les témoins. 2. L'administration de la parathormone corrige l'effet de la parathyroïdectomie sur les éléments collagènes; la teneur de calcium et de cendres était plus élevée que celle des poussins intacts, alors que la teneur des hexosamines est réstée inchangée.
    Abstract: Zusammenfassung Die Entfernung der Nebenschilddrüsen in jungen Küken und die darauffolgende Verabreichung von Parathormon verursachten innerhalb 24 Std in der Zusammensetzung der Epiphysenknorpel Veränderungen, die sich zusammenfassend wie folgt schildern lassen: 1. Die Nebenschilddrüsenentfernung bewirkte eine Erhöhung des Kollagenkomponentengehaltes und eine Verringerung des Calciumgehaltes, während der Hexosamin- und Aschegehalt in den Kontrollen gleich blieb. 2. Die Parathormon-Behandlung korrigierte die Wirkung der Nebenschilddrüsenentfernung auf den Kollagenkomponentengehalt und hatte ein Ansteigen des Calcium- und Aschegehaltes über die entsprechenden Gehalte in nichtoperierten, unbehandelten Küken zur Folge; der Hexosamingehalt änderte sich nicht.
    Notes: Abstract Parathyroidectomy of immature chicks and subsequent administration of parathormone effected, within 24 hours, changes in the composition of the epiphyseal cartilage. These changes can be summarized as follows: 1. Parathyroidectomy increased the levels of collagen constituents and decreased those of calcium, while the levels of hexosamines and of ash remained the same as in controls. 2. Parathormone corrected the effect of parathyroidectomy on the collagen constituents; the levels of calcium and of ash were increased above those of the intact chicks; the levels of hexosamines remained unchanged.
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    Calcified tissue international 3 (1969), S. 38-54 
    ISSN: 1432-0827
    Keywords: Epiphyseal cartilage ; Calcification ; Apatite crystals ; Organic/Inorganic relationships
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les rapports entre composants organiques et inorganiques du cartilage ont été étudiés au niveau des épiphyses tibiales chez des rats de 5 jours et au niveau des jonctions costo-chondrales chez des cobayes d'un mois. Voici les principaux résultats auxquels on est parvenu: (a) Dans les zones où la calcification s'amorce les cristallites d'apatite sont susceptibles d'être facilement éliminés des coupes en araldite et en glycol methacrylate (GMA) après traitement pendant une heure par une solution d'acide formique au 2%. (b) Les zones décalcifiées sont douées d'une faible densité aux électrons et vont exemptes d'une structure quelconque. Seulement la fixation à l'osmium peut révéler du matériel amorphe. (c) Indépendemment du fixateur et du moyen d'inclusion, les coupes décalcifiées, traitées par l'acétate d'uranyl et/ou par le citrate de plomb, montrent de fines structures allongées dont l'aspect est semblable à celui des cristallites. (d) Ces structures ainsi qu'un fond dense interposé prennent l'acide phosphotungstique (PTA) dans les coupes en GMA, une méthode celle-ci qui met en évidence les polysaccharides. (e) Le fond dense ne prend plus le PTA après traitement par la hyaluronidase et en même temps les structures semblables au cristallites apparaissent plus faibles. Après traitement par l'acétate d'uranyl et le citrate de plomb, l'attaque par la hyaluronidase ne produit aucune modification appréciable. Au contraire l'aspect des structures semblables aux cristallites apparait modifié par la digestion à la papaïne. (f) Quand la décalcification à l'EDTA précéde l'enrobage, des amas de matériel fibrillaire se mettent en évidence dans les zones où la calcification s'était amorcée. L'ensemble de ces résultats permet d'établir la nature organique des structures semblables au cristallites et porte aussi à admettre que celles-ci soient formées par de fins filaments cylindriques (digérés par la papaïne) entourés, et probablement engainés par del polysaccharides (digérés par la hyaluronidase et prennant le PTA dans les coupes en GMA).
    Abstract: Zusammenfassung Die Wechselbeziehungen zwischen den organischen und inorganischen Substanzen des verkalkenden Knorpels wurden in der tibialen und femuralen Epiphyse 5 Tage alter Ratten und in den Rippen 1 Monat alter Meerschweinchen untersucht. Die Hauptergebnisse waren: a) Die Hydroxyapatitkristalle der Frühverkalkungszonen können in Araldit- wie auch in Glycolmethylacrilatschnitten (GMA) mit einer lstündigen Behandlung durch 1% ige Ameisensäure leicht entfernt werden. b) Die entkalkten Zonen haben eine sehr niedrige Elektronendichte und enthalten keine sichtbaren Festkörper. Nach Fixierung mit Osmiumsäure kann man darin ein formloses Material erkennen. c) Eine Färbung der Schnitte mit Uranacetat und Bleicitrat, welche von den Fixier- und Einbettungsmitteln nicht beeinträchtigt wird, zeigt feine, längliche Körper (“Kristallgeister”) an, welche morphologisch den Kristallen von Hydroxyapatit gleichen. d) Die Färbung der GMA-Schnitte mit Phosphowolframsäure (PWS), eine Methode welche Polysaccharide anzeigt, hob diese “Kristallgeister” besonders hervor und demonstrierte auch eine dichte dazwischenliegende Grundsubstanz. e) Diese Substanz ist nach Behandlung mit Hyaluronidase nicht mehr färbbar mit PWS; die Färbbarkeit der “Kristallgeister” wird dabei jedoch nur verringert. Die Hyaluronidasebehandlung verändert die Uranacetat- und Bleicitratfärbung nicht. Die Feinstruktur der “Kristallgeister” wird durch Papainbehandlung sehr angegriffen. f) Falls die Schnitte vor dem Einbetten mit EDTA entkalkt werden, können Faserbündel in den Frühzonen der Verkalkung nachgewiesen werden. Diese Ergebnisse bestätigen die organische Natur der “Kristallgeister”. Sie beweisen auch, daß dieselben aus feinen Proteinstäbchen bestehen (verdaulich in Papain) und von Polysacchariden umgeben und vielleicht auch überzogen sind (verdaulich in Hyaluronidase und anfärbbar mit PWS).
    Notes: Abstract The organic/inorganic relationships in calcifying cartilage have been studied in tibialfemoral epiphyses of 5-day-old rats and in costochondral junctions of 1-month-old guinea pigs. The main results are: (a) Apatite crystallites in areas of early cartilage calcification are easily removed from araldite and glycol methacrylate (GMA) sections by 1-hour treatment with 2% formic acid. (b) The decalcified areas have a very low electron density and do not contain recognizable structures. Only after osmium fixation can an amorphous material be found in them. (c) Independently from the fixative and the embedding medium, staining decalcified areas with uranyl acetate and/or lead citrate reveals thin, elongated structures (crystallite ghosts) similar in shape to apatite crystallites. (d) These crystallite ghosts and a dense background are stained by phosphotungstic acid (PTA) in GMA sections, a method which reveals polysaccharides. (e) The dense background is no longer stained by PTA after hyaluronidase digestion and the stainability of the crystallite ghosts is reduced. After uranyl acetate/lead citrate staining there are no recognizable changes due to hyaluronidase. But, on the other hand, the fine structure of the crystallite ghosts is modified by papain digestion. (f) Clusters of fibrillar material are present in the areas of early calcification when EDTA decalcification is carried out before embedding the specimens. These results confirm the organic nature of the crystallite ghosts and suggest that they are formed by thin, rod-like protein/like structures (digested by papain) surrounded, and probably sheathed, by acid polysaccharides (digested by hyaluronidase and stained by PTA in GMA sections).
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    Calcified tissue international 4 (1969), S. 162-173 
    ISSN: 1432-0827
    Keywords: Bone ; Resorption ; Parathyroid ; Bird
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'os médullaire des poules au moment de la ponte ainsi que l'os néoformé de coqs soumis à des substances oestrogéniques, ont été examinés par les méthodes de l'histologie, de l'histochimie, de la microradiographie et de l'alpharadiographie afin de comparer la résorption naturelle à celle produite par la parathormone. Chez les pondeuses, la résorption a été provoquée par la formation de la coquille; chez les coqs, elle s'est produite à la suite de la diminution du taux des oestrogènes. La résorption naturelle de l'os médullaire a été marquée par un accroissement de la basophilie, de l'azurophilie et de la metachromasie, par la diminution graduelle de la densité organique et minérale. Ces modifications ont été observées d'abord dans la portion distale de l'os médullaire; elles se sont progressivement propagées à la région sous corticale. L'extrait parathyroidien semble avoir favorisé tous ces phénomènes, en stimulant l'ostéolyse ostéocytaire et l'ostéoclasie. Il ne nous a pas été possible cependant de nous rendre compte si les ostéoclastes ne se sont attaqués qu'aux portions des travées déja modifiées par l'ostéolyse. Ces résultats concordent avec l'idée que la résorption normale de l'os médullaire de la poule au temps où la coquille de l'oeuf se dépose, est déclanchée par la parathormone. Il en est de même chez le coq à la suite du retrait des oestrogènes.
    Abstract: Zusammenfassung Die Substantia spongiosa der Femora von Legehennen und von Hähnen die mit Östrogen behandelt waren, wurde während spontaner und künstlicher, mit Extrakten von Epithelkörperchen induzierter, Resorption einer histologischen, histochemischen, alpharadiographischen und mikroröntgenographische Untersuchung unterworfen. Die natürliche Resorption wurde bei den Hennen durch die Eischalenproduktion und bei den Hähnen durch Östrogenentzug hervorgerufen. Die natürliche Resorption war durch erhöhte Basophilie, Azurphilie und Metachromasie, sowohl als auch durch verminderter alpharadiographischer und mikroröntgenographischer Dichte der Trabeculae der Substantia spongiosa charakterisiert. Diese Veränderungen wurden zuerst in den zentralen, dem Cavum medullare nächstgelegenen, Teilen der Spongiosa wahrgenommen. Später waren auch die peripheren Teile, mit geringerer Osteocytenkonzentration, betroffen. Diese Veränderungen konnten durch Gaben von Epithelkörperchenextrakten verstärkt werden. Die Resorption der Spongiosa wird durch osteocytische Osteolyse und Osteoklasie bewirkt. Es konnte aber nicht entschieden werden ob diese beiden Prozesse gleichzeitig stattfinden, oder ob die Osteoklasten die Trabeculae erst angreifen, nachdem sie bereits teilweise durch Osteolyse abgebaut worden sind. Diese Resultate stimmen mit der Hypothese überein, daß die natürliche Resorption von Spongiosa während der Eischalenproduktion bei Hennen und nach Entzug von Östrogen bei Hähnen, durch Epithelkörperchenhormonen bedingt ist.
    Notes: Abstract The medullary bone in the femora of laying hens and of oestrogen-treated cocks has been examined by histological, histochemical, alpharadiographic and microroentgenographic techniques while undergoing both natural resorption and resorption induced by injection of parathyroid extract. In the hens, natural resorption was brought about by egg-shell formation and in the cocks by withdrawal of oestrogen. Natural resorption was accompained by increasing basophilia, azurophilia and metachromasia and by decreasing alpharadiographic and microradiographic density of the trabeculae of the medullary bone. These changes were observed initially in the central region (towards the marrow cavity) and subsequently in the peripheral regions also, where the number of osteocytes per unit area of bone was less. Parathyroid extract enhanced all these effects. It appears that resorption of medullary bone was brought about by osteocytic osteolysis and by osteoclasis, but it was not possible to determine whether both processes occurred concurrently or whether the osteoclasts attacked the trabeculae only after they had been partially degraded by osteolysis. These results are consistent with the hypothesis that the natural resorption of medullary bone during egg-shell formation in hens and following the withdrawal of oestrogen in cocks is induced by parathyroid hormone.
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    Calcified tissue international 4 (1969), S. 188-192 
    ISSN: 1432-0827
    Keywords: Serum ; Calcium ; Phosphate ; Calcitonin ; Thyroidectomy ; Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Après ablation des glandes thyroïdes de chiens, sans lèser les glandes parathyroïdiennes supérieurs, les taux en calcium et phosphate sériques et la gravité spécifique sont comparées avec des valeurs d'un groupe de chiens, chez lesquels une intervention simulée est réalisée. Immédiatement après thyroïdectomie, le taux de phosphate est plus élevé que le taux de calcium. Ce taux de phosphate se maintient plus longtemps à un niveau élevé que le taux de calcium, après thyroïdectomie. Le rapport entre l'augmentation du phosphate et le taux initial de phosphate sérique chez chaque animal indique des variations normales de la calcitonine d'un animal à l'autre.
    Abstract: Zusammenfassung Bei Hunden wurde die Thyreoidea entfernt, ohne die Parathyreoidea zu verletzen. Der Gehalt des Serums an Calcium und Phosphat sowie sein spezifisches Gewicht wurden mit den Werten verglichen, welche nach einer Scheinoperation bei einer Kontrollgruppe von Hunden bestimmt wurden. Unmittelbar nach der Thyreoidektomie war der Phosphatspiegel höher als jener des Calciums. Der Phosphatspiegel blieb nach der Thyreoidektomie länger hoch als der Calciumspiegel. Das Verhältnis zwischen dem Phosphatanstieg und dem Ausgangswert des Serumphosphates bei jedem Tier wies auf normale Variationen der Calcitonin-Konzentration bei verschiedenen Tieren hin.
    Notes: Abstract The thyroid glands were removed from dogs without interfering with the superior parathyroid glands. Levels of serum calcium, phosphate, and specific gravity were measured subsequently for 24 hours, and these values were compared with values obtained from a control group of dogs in which a mock operation was done. Immediately after thyroidectomy, the level of phosphate was greater than the calcium level. The phosphate level remained high longer after thyroidectomy than did the calcium level. The relationship between the increase in phosphate level and the initial serum phosphate value in each animal indicated normal variations in calcitonin levels in different animals.
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    Calcified tissue international 4 (1969), S. 224-230 
    ISSN: 1432-0827
    Keywords: Calcinosis ; Calcium ; Iron ; Phosphate ; Collagen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La calcification de la peau (calciphylaxie) provoquée par l'administration sous-cutanée de chlorure de fer chez des rats sensibilisés par le dihydrotachystérol (DHT) est précédée par une déposition sélective de fer (décelable à la microscopie électronique) à la surface des fibres collagènes. Les analyses à la microsonde prouvent que les taux de calcium et de phosphore sont augmentés à l'endroit de l'injection du chlorure de fer même sans l'administration préalable de DHT; cependant, l'apatite ne se forme que chez les animaux prétraités par le DHT. La quantité et le degré de cristallinité de la matière inorganique sont presque identiques au sixième et au trentième jour de l'expérience.
    Abstract: Zusammenfassung Durch elektronenmikroskopische Untersuchungen wurde festgestellt, daß die durch subcutane Verabreichung von Eisenchlorid bei Dihydrotachysterin-sensibilisierten Ratten herbeigeführte Hautverkalkung durch eine selektive Eisenablagerung auf der Oberfläche der Kollagenfibrillen eingeleitet wird. Die Röntgenmikroanalyse zeigt an, daß die lokale Calciumund Phosphorkonzentration bereits nach Eiseninjektion allein ansteigt, während Apatitbildung nur in den mit DHT vorbehandelten Tieren erfolgt. Ausmaß und Menge der Kristallisation sind am 6. und 30. Tage nach Versuchsbeginn fast gleich.
    Notes: Abstract Calcification of the skin (calciphylaxis) induced by the subcutaneous administration of iron chloride to dihydrotachysterol (DHT)-sensitized rats is preceded by the selective deposition of iron (visible with electron microscopic techniques) on the surface of collagen fibrils. Electron probe X-ray microanalysis indicates that the injectionof iron alone suffices to increase local concentrations of calcium and phosphorus; however, apatite formation occurs only in animals pretreated with DHT. The amount and degree of crystallinity of the inorganic material is very similar on the sixth and thirtieth day after the beginning of the experiment.
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    Calcified tissue international 4 (1969), S. 257-259 
    ISSN: 1432-0827
    Keywords: Teeth ; Dentin ; Tubules ; Sclerosis ; Microradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une méthode systématique de comptage par points a été utilisée pour déterminer le volume respectif de la dentine humaine coronaire péricanaliculaire et intercanaliculaire. Contrairement à l'opinion classique, il apparait que la dentine péricanaliculaire constitute une partie relativement importante de la dentine humaine coronaire, surtout au niveau de la moitié interne de la dentine. Dans cette couche, les proportions relatives des deux constitutants sont sensiblement égales.
    Abstract: Zusammenfassung Einc systematische Punktzählmethode wurde angewendet, um die Fraktionen der peritubulären Matrix im menschlichen Dentin der Zahnkrone volumetrisch auszuwerten. Entgegen der früheren Annahme zeigte es sich, daß das peritubuläre Dentin eine relativ große Fraktion des Dentins der Zahnkrone ausmacht; dies war besonders in der inneren Hälfte vom Dentin der Fall, wo die relativen Volumen der beiden Matrices ungefähr gleich groß waren.
    Notes: Abstract A systematic point-count method was utilized to determine the volume fractions of peritubular and intertubular matrix in human coronal dentin. Contrary to previous thought, it was found that peritubular dentin represents a relatively large fraction of human coronal dentin, particularly in the inner one-half of the dentin, where the relative volumes of the two matrices were approximately equal.
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    Calcified tissue international 4 (1969), S. 269-273 
    ISSN: 1432-0827
    Keywords: Bone-Biopsy ; Histology ; Instruments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'intérêt de plus en plus grand manifesté pour les troubles du métabolisme du squelette nécessite en clinique la mise au point de méthodes adéquates pour prélever du matériel osseux. A l'hôpital universitaire d'Utrecht, on se sert actuellement d'un trépan et d'une scie de base. Une description du prélevement, des instruments et de la méthode pour obtenir des coupes nondécalcifiées est présentée.
    Abstract: Zusammenfassung Das zunehmende Interesse an Problemen des Knochenmetabolismus hatte zur Folge, daß geeignete Methoden zur Gewinnung von Knochenbiopsien benötigt wurden. An der Universitätsklinik Utrecht werden jetzt ein Trepan und eine Basensäge benützt. Das Verfahren, die benötigten Instrumente, sowie die Arbeitsweise zur Herstellung von unentkalkten Schliffen werden beschrieben.
    Notes: Abstract The increasing interest in disorders of skeletal metabolism has urged the clinical need for adequate methods to obtain bone material. At the Utrecht University Hospital, a trephine and a base saw are now in use.
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    Calcified tissue international 4 (1969), S. 330-338 
    ISSN: 1432-0827
    Keywords: Collagen ; Electric current ; Electrolysis ; Precipitation ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'effet du courant électrique sur la collagène soluble, en solution dans l'acide acétique dilué, a été étudié pour des voltages, variant de O à 25 volts. Au-dessus de 2,6 volts, la vormation des bandes collagéniques (définies dans ce travail) parait inversement proportionelle, dans le temps, au voltage appliqué. La formation des bandes parait liée au processus d'électrolyse. Les auteurs démontrent que les pH élevés se situent au niveau de la cathode et qu'ils sont suffisants pour induire une précipitation du collagène. Les résultats antérieurs, publiés dans la littérature, décrivant l'action de courant électrique implanté, sont interpretés en fonction du mécanisme étudié au cours de ce travail.
    Abstract: Zusammenfassung Die Wirkung eines elektrischen Stromes auf verdünnte essigsaure Lösungen von löslichem Kollagen wurde bei Spannungen zwischen O und 25 Volt untersucht. Über 2,6 Volt wurde die Bildung von Kollagenbanden (in der Arbeit näher beschrieben) beobachtet, und zwar nach Zeiten, die der angewandten Spannung entgegengesetzt proportional verliefen. Die Bandenbildung wird dem Elektrolyseprozeß zugeschrieben. Wir konnten zeigen, daß sich die hohen pH-Werte rund um die Kathode entwickelten und daß diese genügen, um die Kollagenfällung zu veranlassen. Die Natur dieses Vorganges ist solcher Art, daß erin vivo als Antwort auf durch Stress verursachte Biopotentiale nicht vorkommen kann. Der hier beschriebene Mechanismus erlaubt es, Literaturangaben über den Effekt von implantierten Spannungsquellen zu interpretieren.
    Notes: Abstract The effect of electric current on dilute acetic acid solutions of soluble collagen has been studied for impressed voltages of from 0 to 25 volts. Above 2.6 volts the formation of collagen bands (herein defined) were observed at times inversely proportional to the applied voltage. Band formation is attributed to the process of electrolysis. It has been shown that the high pH values are generated in the area of the cathode, and that they are sufficient to induce collagen to precipitate. The nature of the process is such that it cannot occurin vivo as a response to stress induced biopotentials. Reports in the literature describing the effect of implanted voltage sources are interpreted in terms of the mechanism described here.
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    Calcified tissue international 4 (1969), S. 1-12 
    ISSN: 1432-0827
    Keywords: Bone ; Resorption ; Osteocytes ; Lysosomes ; Collagenase
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    Calcified tissue international 4 (1969), S. 39-47 
    ISSN: 1432-0827
    Keywords: Dehydroepiandrosterone ; Calcification ; Embryo ; Tissue Culture ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les modes d'utilisation de glucose, le contenu de calcium et d'hydroxyproline et la densité cellulaire du perioste de les os frontaux d'embryons de poulet de 12 et 13 jours de developpement, cultivés sur coagulum de plasma, se presentant différenment à chaque âge. Cultivés avec sulfate de déhydroèpiandrostérone en concentration 1 mM, les frontaux de 12 jours montrent un synthese augmentée du matrice osseuse, celle de 13 jours se calcifient à une vélocité significativement plus grande que celle des os contôles. Le degré de calcification au quatrième jour de culture measuré par la relation calcium/hydroxyproline, suit un fonction lineáire avec le logarithme des doses de sulfate de dehydroepiandrostérone employées (0.5, 1,0 et 2,0 mM). Les renseignements obtenus indiquent que les frontaux de 13 jours, cultivés “in vitro” constituent modeles experimentaux appropriés pour étudier l'effet des androgénes sur le tissue osseux.
    Abstract: Zusammenfassung Stirnbeine von Hühnerembryonen an ihrem 12. und 13. Entwicklungstag entnommen und in vitro kultiviert zeigen verschiedene Arten der Glucoseverwertung der Periostzellendichte, des Calcium- und Hydroxyprolingehaltes. Wird Dehydroepiandrosteronsulfat dem Medium in einer 1 mM-Konzentration zugegeben, so beteiligen sich die 12tägigen Stirnbeine vorwiegend an der Knochengewebesynthese, während die 13tägigen signifikant stärker verkalken als die Kontrollen. Gemessen an der Calcium/hydroxyprolin Ratio bildet die Verkalkung der 13tägigen Stirnbeine eine lineare Funktion mit den Logarithmen der verwendeten Dosen von Dehydroepiandrosteronsulfat (0,5, 1,0 und 2,0 mM). Das in vitro kultivierte 13tägige Stirnbein schein ein geeignetes Experimentiermodell zur Studie der Dehydroepiandrosteronsulfatwirkung auf das Knochengewebe zu sein, weil es das grundlegende Phänomen (erhöhte Verkalkung) wiedergibt, welches man auch bei mit Androgenen behandelten Menschen und Tieren beobachtet.
    Notes: Abstract Chick embryo frontal bones at 12 and 13 days of development cultivatedin vitro exhibit different patterns of glucose utilization, periosteal cellular density and calcium and hydroxyproline content. When dehydroepiandrosterone sulfate is added to the medium at a concentration 1 mM, 12-day frontals engage primarily in osteoid tissue synthesis while 13-day frontals calcify at a significantly greater rate than controls. Measured with the ratio calcium/hydroxyproline, the calcification of 13-day frontals follows a linear function with the logarithm of the doses of dehydroepiandrosterone sulfate employed (0.5, 1.0 and 2.0 mM). The 13-day frontal bone cultivatedin vitro seems to be an adequate experimental model for the study of the effects of dehydroepiandrosterone sulfate on bone tissue because it reproduces the basic phenomenon (increased calcification) observed in man and animals treated with androgens.
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    Calcified tissue international 4 (1969), S. 69-77 
    ISSN: 1432-0827
    Keywords: Bone mineral ; Ion exchange ; Fluoride ; Magnesium ; Citrate
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    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'action du Mg2+, du citrate3−, du F− et du SO 4 2− sur les45Ca2+ et32PO 4 3− avec la phase minérale osseuse (extraite de l'éthylènediamine) est déterminée dans des conditions physiologiques. Le Mg2+ se substitue au Ca2+ au niveau de la pellicule liquide adhérente (enveloppe d'hydratation), alors que le citrate3− déplace PO 4 3− , à la fois, de la pellicule liquide adhérente et de la surface cristalline. Ces éléments à affinité pour l'os augmente ainsi la solubilité apparente du minéral osseux. A l'inverse, le F− diminue netterment la concentration de Ca2+ et du PO 4 3− dans la solution environante et dans la pellicule liquide adhérente, en formant probablement une couche de liaison de CaF2 à la surface cristalline. Il y a une absorption nette de Ca2+ et PO 4 3− par la phase solide en présence de Mg2+ et F−, qui ne s'observe pas dans les solutions de citrate. Le SO 4 2− n'affecte pas de façon significative la solubilité, la dissolution ou la croissance du minéral osseux.
    Abstract: Zusammenfassung Die Wirkung von Mg2+, Citrat3−, F− und SO 4 2− auf den Austausch von45Ca2+ und32PO 4 3− mit dem Mineralanteil von Knochen (Ethylendiaminextraktion) wurde unter physiologischen Verhältnissen verfolgt. Mg2+ substituierte das Ca2+ des anhaftenden Flüssigkeitsfilms (Hydratationsschicht), während Citrat3− das PO 4 3− sowohl vom anhaftenden Flüssigkeitsfilm als auch von der Kristalloberfläche ersetzte. Diese vom Knochen angezogenen Elemente erhöhten demzufolge die scheinbare Löslichkeit des Knochenminerals. Dagegen reduzierte F− die Konzentration von Ca2+ und PO 4 3− wesentlich, sowohl in der umgebenden Lösung als auch im anhaftenden Flüssigkeitsfilm, vermutlich durch Bildung einer CaF2-bindenden Schicht auf der Oberfläche des Kristalls. In Gegenwart von Mg2+ und F− nahm diefeste Phase eindeutig Ca2+ und PO 4 3− auf, was bei Citrat3−-haltigen Lösungen nicht der Fall war. SO 4 2− veränderte weder die Löslichkeit noch die Auflösung oder das Wachstum des Knochenminerals significkant.
    Notes: Abstract The effect of Mg2+, citrate3−, F− and SO 4 2− on the exchange of45Ca2+ and32PO 4 3− with the mineral phase of bone (ethylenediamine-extracted) was determined under physiological conditions. Mg2+ substituted for Ca2+ at the adherent liquid film (hydration shell), while citrate3− displaced PO 4 3− from both the adherent liquid film and the crystal surface. These bone-seeking elements thus increased the apparent solubility of bone mineral. In contrast, F− markedly reduced the concentration of Ca2+ and PO 4 3− in both the ambient solution and the adherent liquid film, probably by inducing the formation of a CaF2 boundary layer at the crystal surface. There was a net uptake of Ca2+ and PO 4 3− by the solids phase in the presence of Mg2+ and F−, but not in citrate3− solutions. SO 4 2− did not significantly affect the solubility, dissolution, or growth of bone mineral.
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    Calcified tissue international 4 (1969), S. 94-100 
    ISSN: 1432-0827
    Keywords: Acid ; Base equilibrium ; Acidosis ; Bone ; Resorption ; Metabolism ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
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    Description / Table of Contents: Résumé L'administration chronique de chlorure d ammonium à des rats adultes normaux, soumis à un régime contenant un taux approprié de vitamine D, provoque une ostéoporose. Celle-ci est provoquée par une perte de substance d'os et de minéral osseux, associée à l'augmentation de la résorption osseuse.
    Abstract: Zusammenfassung Chronische Verabreichung von Ammoniumchlorid an normale ausgewachsene männliche Ratten, die eine entsprechende Vitamin-D-haltige Diät erhalten, verursacht die Entwicklung einer Osteoporose. Die Osteoporose entsteht auf Grund eines Verlustes von Knochensubstanz und Knochenmineral, in Begleitung einer erhöhten Knochenresorption.
    Notes: Abstract Excessive administration of ammonium chloride to normal adult male rats receiving a diet adequate in vitamin D caused the development of osteoporosis. The osteoporosis was due to loss of bone substance and bone mineral associated with increased bone resorption.
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    Calcified tissue international 4 (1969), S. 129-135 
    ISSN: 1432-0827
    Keywords: Immunology ; Embryo ; Bovine ; Enamel ; Matrix
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé De l'amélogénine bovine, matrice organique secrétée par les cellules formant l'émail dentaire, est antigénique chez le lapin. La fraction purifiée de gamma-globuline de l'antisérum de lapin, en présence d'amélogénine, dans une boite d'agar à double diffusion, provoque une ligne simple de précipitine. Des fractions isolées de l'amélogénine, par électrophorèse sur gel d'acrylamide et par filtration sur gel de Sephadex, semblent identiques au point de vue antigénique. La fraction antigénique d'amélogénine est séparée de la protéine de l'émail à l'aide d'une colonne Sephadex G-100. L'amélogénine est un système complexe, si l'on se réfère aux résultats d'électrophorèse et de filtration sur gel: ai point de vue immunologique, l'amélogénine se comporte comme un antigène simple.
    Abstract: Zusammenfassung Rinder Amelogenin, die organische Matrix, welche durch die Zahnschmelz-bildenden Zellen sezerniert wird, wirkt als Antigen auf das Kaninchen. Die gereinigte Gammaglobulinfraktion des Kaninchen-Antiserums ergibt auf einer Doppel-Diffusions-Agarplatte eine einzelne Koagulinlinie, wenn sie mit Amelogenin reagiert. Unterfraktionen aus Amelogenin isoliert durch Acrylamid-Gel-Elektrophorese und durch Sephadex-Gel-Filtration wurden in ihrer Antigen-Wirksamkeit identisch gefunden. Die Antigen-Fraktion von Amelogenin wurde durch eine Sephadex G-100-Säule von der Gesamtmenge des Zahnschmelz-Proteins getrennt. Auf Grund seiner bei der Elektrophorese und der Gel-Filtration beobachtetem Eigenschaften ist Amelogenin ein aus verschiedenen Komponenten zusammengesetztes System; Amelogenin wirkt jedoch immunologisch als ein einzelnes Antigen.
    Notes: Abstract Bovine amelogenin, the organic matrix secreted by the dental-enamel-forming cells, is antigenic in the rabbit. The purified gamma globulin fraction of the rabbit antisera when reacted with amelogenin in a double diffusion agar plate forms a single precipitin line. Subfractions isolated from amelogenin by acrylamide gel electrophoresis and by Sephadex gel filtration were found to be antigenically identical. The antigenic fraction of amelogenin was separated from the bulk of the enamel protein by a Sephadex G-100 column. On the basis of its electrophoretic and gel filtration properties, amelogenin is a multi-component system; however, immunologically, amelogenin acts as a single antigen.
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    Calcified tissue international 4 (1969), S. 147-161 
    ISSN: 1432-0827
    Keywords: Cancellous bone ; Trabeculae ; Osteoporosis ; Remodelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une étude de l'épaisseur et de l'espacement des structures osseuses dans l'os d'aspect réticulé du crête iliaque. Les specimens provenant de 67 sujets normaux, ages de 20 à 90 ans, furent enfoncés dans methacrylate et tranches preparés par meulage. L'age croissant est accompagné d'une augmentation de l'espacement entre les structures osseuses, mais pas d'une reduction signifiante de leur épaisseur. Les structures osseuses les plus minces paraissent subir le plus grand remondellage, jugant par l'importance de surfaces de formation et de résorption.
    Abstract: Zusammenfassung Die Dicke der Trabekel und die Weite der Markzwischenräume des Hüftbeinkammes wurden bestimmt. Das in Methacrylat eingebettete Material, welches von 67 Normalpersonen im Alter von 20–90 Jahren stammte, wurde geschnitten und untersucht. Bei zunehmendem Alter vergrößert sich der Raum zwischen den Trabekeln, ohne daß jedoch deren Dicke signifikant vermindert wird. Gemessen am Umfang der Bildungs- und Resorptionsoberfläche scheinen die dünnsten Trabekel dem größten Knochenumbau unterworfen zu sein.
    Notes: Abstract A study of the thickness and spacing of bony structures in the cancellous bone of the iliac crest. Ground sections of methacrylate-embedded material from 67 normal subjects, from 20 to 90 years of age, were examined. Increasing age is accompanied by an increase in the spacing between the bony structures, but not by any significant reduction in their thickness. The thinnest bony structures appear to be undergoing the most remodelling, as judged by the extent of formation and resorption surfaces.
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    Calcified tissue international 4 (1969), S. 174-179 
    ISSN: 1432-0827
    Keywords: Calcium ; Strontium ; Bone ; Mineral
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La proportion Sr/Ca dans l'os est à peu près la même que dans le sérum tandis que les poudres d'hydroxyapatite suspendues dans des solution physiologiques font une distinction contre le strontium. On trouva que la proportion Sr/Ca des fractions de différentes densités d'os compact de tibia de rat en forme de poudre augmentait avec augmentation de la densité jusqu'à une valeur un peu supérieure à celle observée dans le sérum. L'explication pourrait être qu'une barrière cellulaire ôte le calcium par préférence au strontium du fluide d'os ou bien qu'une accentuation précoce de la proportion Sr/Ca dans l'os se réfléchit dans les fractions de densité supérieure.
    Abstract: Zusammenfassung Das Verhältnis Sr/Ca im Knochen ist annähernd dasselbe wie es im Serum vorliegt, während in einer physiologischen Lösung von pulverisiertem Hydroxyapatit das Sr zugunsten des Ca benachteiligt wird. Es wurde festgestellt, daß das Sr/Ca-Verhältnis von Fraktionen verschiedener Dichte von pulverisierten Rattentibiae mit zunehmender Dichte anstieg, und zwar bis zu einem Wert, der etwas höher lag als der im Serum beobachtete. Dies ließe sich so erklären, daß eine Zellbarriere beim Entzug aus der Knochenflüssigkeit Ca dem Sr vorzieht; oder aber daß sich eine frühzeitige Betonung des für den Knochen typischen Sr/Ca-Verhältnisses in den Fraktionen höherer Dichte widerspiegelt.
    Notes: Abstract The Sr/Ca ration in bone is approximately the same as in serum, whereas hydroxyapatite powders suspended in physiological solutions discriminate against strontium. It was found that the Sr/Ca ratio of various density fractions of powdered compact bone of rat tibia increased with increasing density to a value slightly higher than that observed in the serum. The explanation could be that a cellular barrier removes calcium preferentially to strontium from the bone fluid, or that early accentuation of the bone Sr/Ca ration is reflected in the higher density fractions.
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    Calcified tissue international 4 (1969), S. 185-187 
    ISSN: 1432-0827
    Keywords: Cartilage ; Trauma ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La masse du mineral osseux du bout distal femoral a été mesuré dans 54 cas de rupture du cartilage semilunair médial 0–5 années après l'intervention chirurgique. La masse du mineral osseux était diminué. La masse du mineral osseux n'avait aucune tendance de restauration pendant le temps d'observation.
    Abstract: Zusammenfassung In 54 Fällen von medialen Meniscusschäden wurde die Skeletmasse in dem distalen Femurende gemessen 0–5 Jahre nach der Fortnehmung des geschädigten Meniscus. Die Skeletmasse war signifikant vermindert. Im Laufe der Zeit zeigte sich keine Tendenz zur Erhöhung der Skeletmasse.
    Notes: Abstract In 54 cases of ruptured medial semilunar cartilages of the knee joint the bone mineral mass in the distal end of the femur was measured 0–5 years following removal of the injured cartilage. The bone mineral mass was significantly decreased. There was no tendency of restoration of the bone mass with time.
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    Calcified tissue international 4 (1969), S. 180-184 
    ISSN: 1432-0827
    Keywords: Strontium ; Calcium ; Bone ; Shell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des poules ont été nourries avec une alimentation riche en strontium stable. Des concentrations de strontium de 3000 p.p. m. à 50000 p.p.m. montre une augmentation nette en strontium du tibia, alors que le contenu en calcium n'est pas modifié. Les concentrations en calcium sérique diminue, lorsque le strontium alimentaire augmente. Le calcium des coquilles d'oeufs diminue progressivement avec l'augmentation du strontium alimentaire, alors que le contenu en strontium des coquilles présente une augmentation correspondante. Des analyses de diffraction par rayons X des os et des coquilles ne permettent pas de déterminer sous quelle forme le strontium est déposé.
    Abstract: Zusammenfassung Die Resultate einer Verfütterung von hohen stabilen Strontiumdosen an Hühnern werden erläutert. Strontiumzusätze zur Nahrung in der Höhe von 3000–50000 p.p.m. führten zu einer signifikanten Zunahme des Strontiumgehaltes der Tibia und verursachten keine wesentlichen Änderungen des Calciumgehaltes. Die Calciumkonzentration im Plasma verminderte sich, wenn der Nahrung ansteigende Strontiummengen zugegeben wurden. Mit zunehmendem Strontiumzusatz zur Nahrung zeigte der Calciumgehalt der Eischale eine fortlaufende Abnahme, während sich der Strontiumgehalt entsprechend erhöhte. Durch Röntgendiffraktionsanalysen der stark Strontium-haltigen Knochen und Eischalen konnte nicht festgestellt werden, in welcher Form das Strontium abgelagert wurde.
    Notes: Abstract The results of feeding high dietary levels of stable strontium to hens are reported. Dietary levels of strontium from 3,000 p.p.m. to 50,000 p.p.m. showed a significant increase in strontium content of the tibia bone and essentially no change in the calcium content. Plasma calcium concentration was shown to decrease with increasing dietary strontium treatment. Egg shell calcium showed a progressive decrease with increasing dietary strontium treatment, whereas the strontium content has a corresponding increase. X-ray diffraction analyses of bones and shells containing large amounts of strontium were unsuccessful in evaluating the from in which strontium was deposited.
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    Calcified tissue international 4 (1969), S. 202-209 
    ISSN: 1432-0827
    Keywords: Bone ; Radiocalcium ; Ascorbic acid ; Scintillimetry ; Radiocarbon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les auteurs on décrit des méthodes pour la détermination de45Ca plus L-1-14C acide asorbique dans les os d'animaux aprés administration des deux isotopes. Calcium et acide asorbique ont été extraits totalement par l'acide trichloracétique a 6% des os a l'état frais en évitant de détruire l'acide asorbique. La détermination chimique du calcium et de l'acide asorbique selon les méthodes classique a été faite dans des portions de l'échantillon. La détermination de la radioactivité du calcium et de l'acide asorbique a été faite ensuite dans des portions du même échantillon. Du Triton a servi pour le scintillant liquide dans le compteur de scintillation liquide. Un procédé de détermination des deux isotopes dans le meme echantillon a été décrit. Différents critéres on été appliques a chacque étape afin d'établir la validité et les limites d'application de la méthode.
    Abstract: Zusammenfassung Eine Methode ist beschrieben, die die quantitative und radioaktive Bestimmung von45Ca und L-[-L14C] Ascorbinsäure in Knochen von Tieren, denen die beiden Isotopen verabreicht worden sind, erlaubt. Calcium und Ascorbinsäure werden quantitativ mit 6% Trichloressigsäure ausgezogen, wobei die Ascorbinsäure erhalten bleibt. Quantitative Analysen für Calcium und Ascorbinsäure werden nach bekannten Methoden in einem Teil des Extraktes bestimmt und die Bestimmung der Radioaktivität in einem anderen Anteil mit Hilfe eines Flüssigkeits-Szintillations-Zählers durchgeführt. Dem flüssigen Szintillanten wird Triton zugesetzt. Diese Versuchsanordnung ermöglicht außerdem die gleichzeitige Bestimmung der beiden Isotopen im Knochen-Extrakt. Die Methode wurde sorgfältig auf ihre Verwendbarkeit ausgewertet.
    Notes: Abstract Methods were developed for the determination of45Ca plus L-[1-14C] asorbic acid in bones of animals following administration of both isotopes. Asorbic acid and calcium were extracted quantitatively with 6% trichloracetic acid from fresh bone under such mild conditions that asorbic acid was not destroyed. The chemical determinations of calcium and ascorbic acid according to standard procedures were performed in aliquots of the same extract. The determination of the radioactivity of calcium and ascorbic acid were then carried out in aliquots of the same extract. A Triton-containing liquid scintillation fluid was employed for the radioassay of45Ca and L-[1-14C] ascorbic acid in the liquid scintillation spectrometer. A procedure allowing the determination of both isotopes in the same extract is described. A number of criteria were applied to each step, in order to determine the validity and limitations of the procedure.
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    Calcified tissue international 4 (1969), S. 193-201 
    ISSN: 1432-0827
    Keywords: Calcium ; Carbonate ; Gland ; Ultrastructure ; Spherolith
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les cellules activement sécrétantes des glandes riches en calcium deLumbricus terrestris ont une forme en dôme. La partie basale de la cellule présente de nombreux prolongements ramifiés. Ces prolongements contiennent de nombreuses mitochondries, ainsi que des invaginations de la membrane formant des vésicules qui migrent dans diverses parties de la cellule. Le noyau irrégulier est en position centrale. La région supranucléaire contient surtout de l'ergastoplasme, plusieurs appareils de Golgi et de nombreuses granules provenant de l'appareil de Golgi. Ces granules augmentent de taille et sont rejetées dans le sinus de la glande, où elles se modifient et se calcifient pour donner des sphérolithes. Des radioautographics glandulaires, obtenues 1/2 heure après injection de Ca45, montrent une localisation isotopique, située presque exclusivement dans les cellules; 4–24 heures après, l'isotope se localise dans les sphérolithes de la cavité glandulaire. Ces cellules semblent assurer deux fonctions liées à la production de sphérolithes: 1. absorption et transport de calcium de la région basale vers la surface cellulaire et 2. formation d'une matrice protéique qui se calcifiera.
    Abstract: Zusammenfassung Die aktivsezernierenden Zellen der calcifizierenden Drüsen vonLumbricus terrestris sind annähernd kuppelförmig gestaltet. Der untere Teil dieser Zellen besteht aus unzähligen ineinandergreifenden Zellfortsätzen. Diese Fortsätze enthalten zahlreiche Mitochondrien und membranöse Einstülpungen, welche Bläschen bilden, die zu den verschiedenen Regionen der Zelle wandern. Der Zellkern ist unregelmäßig und zentral angeordnet. Die supranukleäre Region ist zu einem großen Teil mit grobem endoplasmatischem Reticulum und mehreren Golgi-Komplexen sowie zahlreichen Granula, die von den Golgi-Komplexen stammen, ausgefüllt. Diese Granula vergrößern sich und werden in den Drüseninus ausgestoßen, wo sie schließlich reorganisiert und mineralisiert werden, um Sphärolithen zu bilden. 1/2 Std nach Injektion von Ca45 wurde die Drüse entfernt; eine Radioautographie zeigte, daß das Isotop beinahe ausschließlich in den Zellen lokalisiert war; 4–24 Std später befand sich das Isotopin den Sphärolithen der Drüsenhöhlung. Diese Zellen sind anscheinend an zwei für die Bildung von mineralisierten Sphärolithen notwendigen Funktionen beteiligt: 1. an der Calcium-Absorption und deren Transport von der Basalregion bis zur Zelloberfläche; 2. an der Bildung einer Proteinmatrix, in welcher die Mineralisation stattfindet.
    Notes: Abstract The actively-secreting cells of the calciferous glands ofLumbricus terrestris are roughly dome shaped. The basal part of the cell consists of numerous interdigitating cell processes. These processes contain numerous mitochondria and membranous infoldings, forming vesicles which migrate to various regions of the cell. The nucleus is irregular and centrally located. The supranuclear region is occupied to a great extent by the rough endoplasmic reticulum, several Golgi complexes and numerous granules derived from the Golgi complexes. These granules enlarge and are extruded into the gland sinus, where they eventually become reorganized and mineralized to give rise to spheroliths. Radioautographs of glands removed 30 min following injection of45Ca showed uptake of the isotope located almost exclusively in the cells; 4–24 h later the isotope was located in the spheroliths in the gland cavity. These cells apparently perform two functions necessary for the production of mineralized spheroliths, 1, absorption and transport of calcium from the basal region to the cell surface and 2, the elaboration of a protein matrix in which mineralization occurs.
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    Calcified tissue international 4 (1969), S. 274-290 
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    Calcified tissue international 4 (1969), S. 260-268 
    ISSN: 1432-0827
    Keywords: Cartilage ; Histochemistry ; Staining ; Protein ; Polysaccharide ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des coupes de cartilage épiphysaire frais de jeunes rats, effectuées à la main, sont colorées à pH=4,5 dans des solutions à 0,01% de divers colorants cationiques, appartenant aux groupes de la thiazine, oxazine, azine, triphénylméthane, acridine, et phthallocyanine. Les granules intracellulaires métachromatiques, mises en évidence antérieurement par le bleu de toluidine, sont également identifiées à l'aide de l'azur A, le bleu de méthylène et le bleu de crésyl. Les granules se colorent moins bien à la thionine, le rouge neutre, la safranine O, le bleu de toluylène et l'acridine orange. Dans les conditions utilisées, la matrice de la zone de réserve et la matrice de la zone hypertrophique inférieure (en voie de calcification) se colorent, alors que les matrices des zones prolifératives et hypertrophiques supérieures ne prennent pas les colorants. La gallocyanine, le violet cristal, la fuchsine basique, l'azocarmin B, le bleu de gallamine et la bleu alcian ne se colorent pas ou donnent des réactions colorées différentes de celles décrites ci-dessus. Il semble que le pK et le poids moléculaire des colorants jouent un rôle important, mais ils ne paraissent pas être les seuls facteurs intervenant dans la coloration des granules. Un changement, lié à la calcification, semble intervenir au niveau du matériel métachromatique (probablement des polysaccharides protéiques), aussi bien dans la matrice que les cellules cartilagineuses épiphysaires.
    Abstract: Zusammenfassung Handpräparierte Schnitte von frischem Epiphysenknorpel junger Ratten wurden bei einem pH von 4,5 in 0,01% igen Lösungen verschiedener kationischer Farbstoffe folgender Klassen gefärbt: Thiazin, Oxazin, Azin, Triphenylmethan, Acridin und Phthalocyanin. Die intracellulären β-und γ-metachromatischen Granula, erstmals mit Toluidinblau im frischen Gewebe nachgewiesen, konnten auch gut mit Azur A, Methylenblau und Brillantkresylblau dargestellt werden. Die Granula konnten ebenfalls, aber weniger gut, mit Thionin, Neutralrot, Safranin D, Toluylenblau und Acridinorange gefärbt werden. Unter diesen Färbungsbedingungen werden die inaktive Matrixzone und die untere hypertrophische (verkalkende) Matrixzone angefärbt, während die proliferative und die obere hypertrophische Matrixzone sich nicht färben. Gallocyanin, Kristallviolett, basisches Fuchsin, Azokarmin B, Gallaminblau und Alzianblau färbten entweder gar nicht, oder gaben ein anderes als das obenbeschriebene Färbemuster. Es wird vorgeschlagen, daß das pK und das Molekulargewicht der Farbstoffe wichtig aber nicht unbedingt die einzigen Faktoren sind, die die Färbung der Granula bestimmen. Die Resultate zeigen, daß eine Veränderung im metachromatischen Material (vermutlich Proteinpolysaccharide) vorliegt, und zwar sowohl in der Matrix als in den Zellen des Epiphysenknorpels; diese Veränderung scheint im Zusammenhang mit der Verkalkung zu stehen.
    Notes: Abstract Hand-cut sections of fresh epiphyseal cartilage from young rats were stained at pH 4.5 in 0.01% solutions of various cationic dyes of the thiazine, oxazine, azine, triphenylmethane, acridine, and phthallocyanin classes. The intracellular β-and γ-metachromatic granules, previously demonstrated in fresh tissues with toluidine blue, were also demonstrated well with azure A, methylene blue, and brilliant cresyl blue. The granules were also demonstrated, but not as well, by thionin, neutral red, safranin O, toluylene blue, and acridine orange. Under the conditions of staining, the reserve zone matrix and the lower hypertrophic (calcifying) zone matrix stained, whereas the proliferative and upper hypertrophic zone matrix did not stain. Gallocyanin, crystal violet, basic fuchsin, azocarmine B, gallamine blue, and alcian blue either did not stain, or gave a different pattern of staining from that described above. It is suggested that the pK and molecular weight of the dyes are important, but not necessarily the only factors in determining the staining of the granules. The results indicate that there is a change in the metachromatic material (presumably proteinpolysaccharide) in both the matrix and cells of epiphyseal cartilage, which appears to be related to calcification.
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    Calcified tissue international 4 (1969), S. 291-304 
    ISSN: 1432-0827
    Keywords: Bone ; Fluorescence ; Resorption ; Deposition ; Calcium ; Microradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Divers agents chimiques, colorés, fluorescents et se localisant dans les os, à savoir la tétracycline, l'alazazine rouge S et le DCAF, ont été administré en série à des rats sevrés et on a mesuré le taux de la formation et de la résorption osseuse sur les coupes transversales du tiers supérieur de la diaphyse. Ici la formation osseuse périostale s'effectue progressivement avec peu de changement endostéal. Avec alimentation carnée, la croissance des rats est significativement restreinte pendant la première semaine, mais se rétablit ensuite. Bien qu'il y ait croissance des os, ceux-ci ne se minéralisent pas normalement et ils deviennent rapidement fragiles et amincis. La résorption osseuse est lente d'abord, puis s'accelère pendant 2–3 semaines pour atteindre un taux de 15μ par jour, après quoi elle se ralentit de nouveau. Bien que le taux de formation osseuse soit réduit, en comparaison avec celui des os normaux, la résorption s'effectue environ deux à trois fois plus rapidement que la croissance osseuse. Des études microradiographiques sur des rats à régime carné mais carencés en calcium ont permis la constatation suivante: tandis que la résorption s'effectue à la marge endostéale et que la formation osseuse a lieu sur l'aspect périostéal, la matière osseuse nouvellement formée est moins calcifiéc que chez les témoins.
    Abstract: Zusammenfassung Einige farbige, fluoreszierende, knochensuchende Chemikalien, z. B. Tetracyclin, Alazarin-Rot S und CDAF, wurden nacheinander an entwöhnten Ratten verabreicht, worauf man die Knochenbildungs- und Knochenresorptionswerte an hartgeschliffenen Schnitten des oberen Drittels der Diaphyse gemessen hat. Hier findet fortschreitend periostale Knochenbildung statt, mit geringer Veränderung des Endosteums. Bei Fleischdiät wird das Körperwachstum während der ersten Woche erheblich beschränkt; danach aber normalisiert es sich wieder. Obwohl die Knochen noch wachsen, zeigen sie keine normale Mineralisierung und werden schnell zerbrechlich und dünn. Die Knochenresorption ist anfangs langsam, dann beschleunigt sie sich während einer Zeitspanne von 2–3 Wochen bis auf 15 μ pro Tag, um sich dann wieder zu verlangsamen. Während die Knochenbildungsgeschwindigkeit relativ zum Normalwert heruntergesetzt wird, verläuft die Resorption ungefähr 2–3mal so schnell wie die Knochenbildung. Mikroradiographische Untersuchungen an mit Fleisch ernährten Ca-armen Ratten haben bestätigt, daß während die Resorption am Endosteumrande stattfindet und sich die Knochenbildung an der Periostenfläche fortsetzt, die neugebildete Knochensubstanz weniger kalzifiziert ist, als die der Kontrolltiere.
    Notes: Abstract Different coloured, fluorescent bone-seeking chemicals, viz., tetracycline, Alizarin Red S, and DCAF, have been administered sequentially to weanling rats and the rate of formation and resorption of bone measured from hard-ground cross sections of the upper third of the diaphysis of the femur. On a meat diet, bodily growth is significantly restricted for the first week and then recovery occurs. While bones grow they fail to mineralize normally and rapidly become fragile and rarefied. Resorption of bone is at first slow, then accelerates for a period of 2–3 weeks to about 15μ/day and then slows again. While the rate of bone formation is reduced relative to normal bone, resorption proceeds at approximately two to three times the rate of bone growth. Microradiographic studies confirm tht while resorption occurs on the endosteal margin and formation proceeds on the periosteal aspect of meat fed Ca-deficient rats, new bone is less calcified than that in control animals.
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    Calcified tissue international 4 (1969), S. 314-329 
    ISSN: 1432-0827
    Keywords: Sponge ; Spicules ; Calcite ; Analysis ; Specific gravity ; Speciation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Nous donnons les résultats d'analyses chimiques, d'examens aux rayons infra-rouge, et d'examens par diffraction des rayons-X, des spicules de sept espèces des Éponges Calcaires avec aussi les valeurs de gravité spcéifique. Les spicules se composent de calcite et de magnésium. Nous avons découvert des traces de quartz, mais nous les attribuons à la contamination. Nous avons cherché l'aragonite, sans la trouver, bien que la présence du quartz en rende plus difficile la recherche. Le contenu de Mg2+ a varié de 1,25 à 3,15 pour cent d'une espèce à l'autre, s'élevant selon la grandeur des spicules dans les deux espèces que nous avons étudiées. Il était aussi en corrélation étroite avec le déplacement du sommet 112 de diffraction. Des composants présents en quantité moindre, et dont nous avons estimé le pourcentage, se trouvaient être Sr2+, Na+ et SO 4 2− . Sr2+ était relativement invariable, les deux autres étaient variables. Nous avons découvert aussi des traces de Al3+, Si, Mn2+, Ba2+ et Li+. Les valeurs de gravité spécifique s'échelonnaient de 2,58 à 2,62, les spicules plus petits fournissant la plus grande variation. Nous considérons la composition par rapport à la sécrétion de spicules et à la classification de la Calcarea.
    Abstract: Zusammenfassung Die Ergebnisse von chemischen, röntgenographischen und infraroten Analysen, zusammen mit Bestimmungen von spezifischem Gewicht, werden für die Nadeln von 7 species der Kalkschwämme dargestellt. Die Nadeln setzen sich zusammen aus magnesiahaltigem Calcit. Spuren von Quartz wurden nachgewiesen, die sich aber auf Verunreinigungen zurückführen lassen. Aragonit wurde gesucht, aber nicht gefunden, obgleich die Anwesenheit von Quartz seine Feststellung erschwert. Der Mg2+-Inhalt variierte von 1,25–3,15% zwischen den Species, und nahm mit wachsender Nadelgröße bei den beiden untersuchten Species zu; es gibt auch enge Wechselbeziehungen zur Absetzung der Calcit-112-Diffraktionsspitze. Es gibt vermutlich geringere Mengen von Sr2+, Na+, und SO 4 2− . Sr2+ war relative beständig, die anderen zwei veränderlich. Spuren von Al3+, Si, Mn2+, Ba2+ und Li+ wurden auch nachgewiesen. Die durchschnittlichen spezifischen Gewichte veränderten sich von 2,58–2,62, und kleinere Nadeln variieren stärker. Die Zusammensetzung wird mit Hinsicht auf die Ausscheidung der Nadeln und die Klassenordnung der Kalkschwämme betrachtet.
    Notes: Abstract The results of chemical, X-ray diffraction and infra-red analyses, together with specific gravity determinations, are presented for the spicules of seven species of Calcarea. The spicules are composed of magnesian calcite. Traces of quartz were detected, but are ascribed to contamination. Aragonite was sought but not proven, although the presence of quartz complicates its detection. The Mg content varied from 1.25–3.15% between species, and increased with spicule size in the two species studied; it also correlated closely with the displacement of the calcite 112 diffraction peak. Minor constituents estimated were Sr2+, Na+ and SO 4 2− :Sr2+ was relatively constant, the other two variable. Traces of Al3+, Si, Mn2+ and Li+ were also detected. Average specific gravities ranged from 2.58–2.62, smaller spicules having a wider range Composition is considered in relation to spicule secretion and classification of the Calcarea.
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    Calcified tissue international 4 (1969), S. 359-365 
    ISSN: 1432-0827
    Keywords: Metals ; Ions ; Buffers ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'action de divers ions métalliques polyvalents sur les propriétés métastables d'un tampon calcifiable a été étudiée. A des concentrations de 1 μM ou moins, les ions Pb2+, F2+, Fe3+, Cr3+, Bi3+ et Al3+ déstabilisent le tampon. Il semble que les phosphates insolubles formés par ces ions déclanchent la précipitation de l'apatite. L'importance de ces résultats dans l'étiologie des calcifications pathologiques et la calciphylaxie est décrite.
    Abstract: Zusammenfassung Die Wirkung von verschiedenen polyvalenten Metallionen auf die Metastabilität eines Calcifikationspuffers wurde untersucht. Bei Konzentrationen von 1 μM oder weniger wird der Puffer durch Pb2+, Fe2+, Fe2+, Cr3+, Bi3+ und Al3+ entstabilisiert. Die Resultate lassen vermuten, daß unlösliche Phosphate, die mit diesen Ionen entstehen, eine Fällung von Apatit veranlassen. Die Bedeutung dieser Befunde bei pathologischen Verkalkungen und Calciphylaxis werden besprochen.
    Notes: Abstract The effect was studied of various polyvalent metal ions on the metastability of a calcification buffer. At concentration of 1 μM or less, Pb2+, Fe2+, Fe3+, Cr3+, Bi3+ and Al3+ ions were found to destabilize the buffer. The results suggest that insoluble phosphates formed by these ions initiate the precipitation of calcium apatite. The implications of these findings to pathological calcification and calciphylaxis are discussed.
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    Calcified tissue international 4 (1969), S. 60-68 
    ISSN: 1432-0827
    Keywords: Calcium phosphate ; Osteocyte ; Electron microscope ; Electron probe ; Osteolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Nous avons administé 0,6 mg de Dihydrotachystérol à des rats, à raison de 2×0,1 mg par semaine. Les observations suivantes on été faites au moyen du microscope électronique et du radioanalyseur à microsonde électronique. 1. La gaine mucopolysaccharidique péri-ostéocytaire est nettement élargie ches les animaux traités; elle contient un matériel de haute densité électronique constitué de fines particules arrondies ou allongées, variables quant à la quantité et la répartition; 2. La microanalyse met en évidence, dans la gaine péri-ostéocytaire, das quantités considérables de calcium et de phosphore. Le rapport Ca/P peut atteindre celui de l'apatite pure. Nous considérons les particules dérites comme des germes de nucléation de phosphate de calcium. Nous pensons que par suite d'une augmentation pathologique du métabolisme calcique, des sels calciques sont libérés à partir de la substance minéralisée entourant la lacune ostéocytaire, en quantités telles qu'ils deviennent morphologiquement apparents dans la gaine péricellulaire.
    Abstract: Zusammenfassung Ratten wurden mit 0,6 mg Dihydrotachysterin (0,1 mg zweimal wöchentlich) behandelt. Dabei wurden mit Hilfe des Elektronenmikroskops und der elektronenmikroskopischen Elektronentrahl-Mikroanalyse folgende Befunde erhoben: 1. Bei den behandelten Tieren war die periosteocytäre Mucopolysaccharidscheide deutlich verbreitert. Sie enthielt, in wechselnder Menge und Verteilung, kleine rundliche oder nadelförmige, elektronendichte Partikel. 2. Mit der elektronenmikroskopischen Elektronentrahl-Mikroanalyse konnten in der Zell-scheide große Mengen von Calcium und Phosphor nachgewiesen werden. Das Verhältnis Ca/P kann die Werte reinen Apatits erreichen. Wir halten die elektronendichten Partikel für Calciumphosphat-Keime. Im Rahmen eines pathologisch gesteigerten Calciumstoffwechsels werden Calciumsalze in solchen Mengen aus der die Osteocytenhöhle umgebenden mineralisierten Grundsubstanz freigesetzt, daß sie morphologisch nachweisbar werden.
    Notes: Abstract Rats were treated with 0.6 mg (0.1 mg twice a week) of dihydrotachysterol and the following electron microscopic and electron-probe X-ray microanalytical findings were made: 1. The periosteocytic mucopolysaccharide sheath is definitely enlarged in the treated animals. In it were found, in variable quantities and distribution, collections of round or needle-shaped electron-dense particles. 2. By electron-probe X-ray microanalysis, high concentrations of calcium and phosphorus were detected in the cell sheath, where the Ca/P ratio may reach the value of pure apatite. The electron-dense particles are considered to be calcium phosphate nuclei. It is postulated that in consequence of the pathologically increased calcium turnover, calcium salts are set free from the mineralized matrix surrounding the osteocyte lacuna in such quantities as to become morphologically detectable in the cell sheath.
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    Chromosoma 26 (1969), S. 1-6 
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Variation in chromosome number from 2n=9 to 2n=7 was found in a species of leafhopper, Alodeltocephalus draba. It is argued that this variation is due to chromosome fusion and that A. draba is presently evolving to a lower number. The process of reduction is more advanced in some populations than in others.
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    Chromosoma 26 (1969), S. 7-21 
    ISSN: 1432-0886
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    Notes: Abstract French populations of Chorthippus parallelus like those from Britain are polymorphic with respect to supernumerary segments on the M7 and S8 chromosomes. The pattern of polymorphism parallels that of British material on both morphological and behavioural grounds. It agrees also in its effect on mean cell chiasma frequency and the absence of any effect on between cell variance. Finally the agreement extends also to the distribution of karyotypes within populations, those of the S8 showing a Hardy-Weinberg distribution whereas those of the M7 show a deficiency of structurally heterozygous types. All these parallels imply a common origin for the British and French material, an origin which, so we must suppose, antedated the physical separation of Britain and France some 8,000 years ago.
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    Notes: Abstract Chondrostean and holostean fish of today are leftover relics: they share some characteristics with the venturesome crossopterygian fish, which launched the evolution of terrestrial vertebrates about 280 million years ago. The chromosome complements and DNA values of one chondrostean and two holostean species as well as one holocephalian species were studied. Their DNA values varied from 37% to 50% of that of mammals, and three of the species contained dot-like microchromosomes in their diploid complements. Their genome size and karyological characteristics are quite similar to those possessed by one group of reptiles and by avian species.
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    Chromosoma 26 (1969), S. 22-34 
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    Notes: Abstract In chiasmatic meiosis of mosquitoes, ascomycetes and lilies the synaptinemal complex (SC) disassociates from the bivalent before metaphase I. Conversely, in the achiasmatic meiosis of Bolbe nigra, the SC remains associated with the bivalent during first metaphase. Light microscopy reveals mid-bodies between disjoining half-bivalents during early first anaphase in Bolbe. Optically controlled serial sections for electron microscopy show that the mid-bodies seen in light micrographs and synaptinemal complexes seen in electron micrographs are the same structure. Electron micrographs indicate that the SC breaks transversely at a point corresponding to the chromosomal kinetochore during anaphase I as the chromatin and the SC begin to separate. During telophase I, SC remnants are at the poles with the chromosomes or between poles. Presently, the evidence is inadequate to state whether the SC serves alternately or simultaneously as a biological contrivance for conjunction and crossing-over or singly as a device for one of these phenomena.
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    Chromosoma 26 (1969), S. 119-129 
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    Notes: Abstract The prophase stages of meiosis in Neurospora crassa are re-examined following McClintock (1945) and Singleton (1953). A diffuse chromosome stage occurring between pachynema and diakinesis is described. It is proposed that the diffuse stage does not necessarily represent a condition of intense gene activity in the sense of directing the metabolic activity of the ascus.
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    Chromosoma 26 (1969), S. 105-118 
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    Notes: Abstract Earlier studies have demonstrated convincing correlations between the distribution patterns of chiasmata and of U-type exchanges within bivalents. On the basis of this evidence and other considerations it has been proposed that these contrasting meiotic exchange events are related in origin, and that U-type exchanges, giving rise to bridge and fragment configurations, arise as errors in crossing-over and chiasma formation. This hypothesis is given further consideration in the present report and further correlated distributions of chiasmata and U-type exchanges are presented. These correlations involve the distribution patterns of exchanges between bivalents and between the two arns of one particular bivalent which is consistently marked by the presence of localised neocentric activity. The relationships of these exchange distributions to chromosome length are also investigated and as a result it becomes clear that a mutual dependence of the two types of exchange on chromosome length cannot account for the observed correlations. The total evidence relating to the hypothesis of a causal connection between chiasmata and U-type exchanges is reviewed and critically assessed.
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    Description / Table of Contents: Zusammenfassung 1. Spätlarvale Speicheldrüsen von Drosophila melanogaster wurden während 6–120 h im Abdomen adulter Wirte kultiviert und auf Veränderungen im Chromosomenarm III L geprüft. 2. Durch die Kultur in vivo werden vor allem zwei auffallende Puffs induziert, die in 68B und 78E lokalisiert sind. Diese zwei Loci zeigen in der Normogenese nie eine Puffaktivität. 3. Innerhalb einer Drüse treten nach Kultur in vivo große Unterschiede in der Puffgröße auf. Die Variabilität reicht vom inaktiven Band bis zum großen Puff. 4. Frequenz und Größe des Puffs in 68B sind von der Kulturdauer in vivo unabhängig. Dagegen erscheint der Puff 78E erst nach 12 h Kultur in höheren Frequenzen. 5. Die Aktivierung des Bandes in 68 B wird in frischgeschlüpften, nicht ausgefärbten Weibchen und in Männchen besonders gefördert. 6. Werden Vorderhälften — je nach Serie — aus 6–9 h alten Embryonen während 5–14 Tagen im Fliegenabdomen kultiviert, kann die spätere embryonale und die larvale Entwicklung und Differenzierung allein im Adultmilieu ablaufen. Mit Sicherheit konnten Speicheldrüsen, Imaginalscheiben, Fettkörper, Malpighische Gefäße und Muskelfasern identifiziert werden. Selbst in 4 h alten Embryonalspendern können sich nach Adultaufenthalt polytäne Speicheldrüsenchromosomen entwickeln. 7. Die Chromosomen in Speicheldrüsen aus embryonalen Spendern erreichen nach 11 Tagen Kultur im Adultabdomen, die für die Normogenese typische Endgröße. In vielen Kernen erfolgt noch ein zusätzliches Wachstum, das zu übergroßen („supergiant“) Chromosomen führt. 8. Im kultivierten embryonalen Material entwickeln sich, wie bei implantierten larvalen Speicheldrüsen, in den polytänen Chromosomen der 68B- und 78E-Puff.
    Notes: Abstract Salivary glands from late third instar larvae of Drosophila melanogaster were transplanted into the abdomens of adult female and male flies and were kept in this medium from 6 to 120 h. Changes in the puffing pattern of chromosome arm III L were studied after the culture in vivo. Two noticeable puffs are induced. They are located in 68 B and 78 E. Neither of these loci show activity during normal development. — Front halves of embryos (6 to 9 h of age) were also transferred into adults. After 5 to 13 days in vivo they are able to develop and differentiate larval structures. Salivary glands, imaginal discs, fat body, Malpighian tubules and muscle fibers could be identified. Even 4 h old embryos can form polytene salivary gland chromosomes after a 13 day culture. These chromosomes can reach sizes comparable with the maximal size in normal development. In some nuclei an extensive growth leads to “supergiant” chromosomes. The puffs in 68B and 78E are formed in the polytenic chromosomes from embryonic implants as in cultured larval salivary gland chromosomes.
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    Chromosoma 26 (1969), S. 130-139 
    ISSN: 1432-0886
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    Topics: Biology , Medicine
    Notes: Abstract In the progeny of a trisomic type for chromosome 6, Purple, a 16-chromosome type was obtained, which had a pair of new metacentric chromosome 6 in excess. The new metacentric chromosome 6 was shorter than any of the 14 chromosomes of normal barley complement and showed a heteropycnotic nature at late prophase in somatic mitosis. At metaphase I in the plants with 14+one metacentric chromosome 6 (2n=15) the chromosome configuration was exclusively 7II+1I indicating that the extra metacentric chromosome 6 could not associate with the normal chromosome 6. At diakinesis and metaphase I in the new 16-chromosome plants most of the sporocytes showed 8IIor 7II+2I. Neither tetravalents nor trivalents were observed at meiosis. The chromosome behaviour at anaphase I and later stages of meiosis was regular in general, resulted in a fairly high pollen fertility of about 61 per cent. Seed fertility however, was very low. The transmission rate of the new metacentric chromosome 6 through the pollen was extremely low in 16-chromosome plants. Possible origin of new basic number and B-chromosome in diploid level through trisomic condition was suggested (Summary see p. 138).
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    Chromosoma 26 (1969), S. 140-147 
    ISSN: 1432-0886
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    Notes: Abstract The standard complement of Myrmeleotettix maculatus includes a pair of L 3 metacentric chromosomes but throughout the germ line of a structurally mutant male individual one of these had been replaced by two telocentrics. These chromosomes divided normally at mitosis and at meiosis paired completely with the arms of the remaining L 3. There was no tendency for the two terminal centromeres to fuse. At first anaphase the two rods usually segregated from the metacentric which resulted in the formation of a high percentage of balanced gametes. On the basis of this evidence and the morphological appearance of the centric region it has been concluded that the derived telocentrics evolved following misdivision through the inner zone of the metacentric centromere. In view of their apparent stability it has been proposed that, contrary to certain beliefs, centric fission may have played an important role during karyotype evolution in the Acrididae.
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    Chromosoma 26 (1969), S. 148-168 
    ISSN: 1432-0886
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    Notes: Abstract Karyotype analysis and morphometric measurement of the chromosomes of eleven species of Indian birds are described. The unequivocal identification of W chromosome in the females of five species of the present investigation further strengthens the generalisation that, at least in Carinatae, the sex chromosome constitutions are of ZZ and ZW types in males and females respectively. — The chromosomes of different species of birds so far worked out in each order have been compared using quantitative methods and tentative conclusions have been drawn regarding chromosomal affinities between species of different taxonomic categories.
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    Chromosoma 26 (1969), S. 41-75 
    ISSN: 1432-0886
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    Description / Table of Contents: Zusammenfassung 1. Die interphasischen Oogonienkerne von Gryllus domesticus enthalten mehrere kleine, kugelförmige DNS-Körper, die von Nukleolen umhüllt sind (Abb. 3 und 4). Während der Kernteilungen lockern sich die DNS-Körper in dünne Fäden auf (Abb. 5 und 6) und werden in vielen Fällen unsichtbar. Diese Fäden sind zusätzliche DNS-Elemente neben den 22 Metaphasechromosomen. Daher ist die Annahme, DNS Körper und X-Chromosomen seien miteinander identisch, hinfällig (vgl. dagegen Sotelo und Wettstein, 1964). In den älteren Oogonien vermindert sich die Anzahl der DNS-Körper zugunsten einer deutlichen Größenzunahme der wenigen Körper, die übrigbleiben. 2. Die Primäroocyten besitzen im Lepto- und Zygotänstadium meist nur noch einen einzigen, allerdings sehr viel größer gewordenen DNS-Körper. Dieser zerteilt sich im Pachy- und Diplotän vollständig in einzelne Fasern, die sich schließlich voneinander lösen und im Kernraum ausbreiten (Abb. 10 und 11). Mit der Entspiralisierung des DNS-Körpers läuft eine Vermehrung der Nukleolen parallel, die an den DNS-Fasern entstehen und sich mit diesen gemeinsam über weite Bereiche des Oocytenkerns verteilen (Abb. 11). Frühere Untersuchungen (Kunz, 1967) hatten ergeben, daß diese Nukleolen wie die multiplen Oocytennukleolen der Amphibien ringförmig gestaltet sind. Die den Nukleolen zugrunde liegende DNS geht bei Gryllus auf den DNS-Körper der frühen Stadien zurück. 3. Auf autoradiographischem Wege wurde ein gegenüber den Chromosomen asynchroner Thymidineinbau im DNS-Körper der Oogonien und Oocyten festgestellt (Abb. 7). 4. Laterale Lampenbürstenschleifen, die zuerst im Zygotän sichtbar werden, entstehen nicht nur in der weiblichen Meiose, sondern auch in den entsprechenden Prophasestadien der Männchen (Abb. 8). 5. Ein auffallendes, positiv heteropyknotisches Chromozentrum ist auch in den Spermatogonien und meiotischen Prophasestadien der Männchen enthalten (Abb. 8), ohne jedoch regelmäßig mit dem Nukleolus verbunden zu sein (Abb. 9 und 14). Es handelt sich hierbei nicht um einen akzessorischen DNS-Körper wie in den weiblichen Keimzellen, sondern um das univalente X-Chromosom. 6. Diploide somatische Zellen enthalten nur zu einem geringen Prozentsatz zwei Nukleolen; in den meisten Fällen sind die beiden Nukleolen zu einem einzigen Gebilde verschmolzen. Im Vorkommen zweier Nukleolen liegt zwischen Männchen und Weibchen kein signifikanter Unterschied vor. Das wird als Hinweis dafür gewertet, daß der Nukleolenbildungsort auf einem Autosomenpaar liegt, nicht auf den (beim Weibchen doppelt, beim Männchen nur in Einzahl vorhandenen) Geschlechtschromosomen. 7. In der Oogenese von Gryllus ist die Nukleolen-DNS in hohem Maße vervielfacht, während die übrigen Gene (in der G2-Phase) nur in vierfachem Satz vorliegen. Der Grund für die selektive Multiplikation der Gene des Nukleolenbildungsortes liegt wahrscheinlich darin, daß in der Oogenese die gesamte ribosomale RNS für einen vielzelligen Embryo aufgebaut werden muß, andererseits aber in der Keimbahn keine endo-mitotische DNS-Vermehrung möglich ist.
    Notes: Abstract The early stages of female and male germ cells have been investigated in Feulgen squash preparations, in unfixed state with phase contrast optics and in the electron microscope. The DNA axes of the ring-shaped multiple nucleoli in the growing oocytes of Gryllus arise from compact DNA bodies which are found in oogonia of young larvae and in oocytes prior to the growth period. The nuclei of the early oogonia contain several little DNA bodies whereas young oocytes at leptotene, zygotene and pachytene have only one body which is bigger than at earlier stages (Pig. 3). At metaphase and anaphase during oogonial mitosis the DNA body has a filamentous shape distinguishable from the compact chromosomes (Fig. 5). In oogonia as well as at leptotene and zygotene stages, nucleoli are produced in the peripheral, uncoiled parts of each DNA body whereas the compact interior is completely free of nucleolar material (Figs. 4, 12). At pachytene, the whole DNA body begins to despiralize, and single DNA strands are released into the nucleoplasm. These strands form hundreds of multiple nucleoli which finally are dispersed in the germinal vesicle (Fig. 11). — Incorporation studies with radio-active thymidine have shown that DNA synthesis in the DNA body is not synchronous with the S-phase of the chromosomes (Fig. 7). — The DNA body is an own formation distinct from the sex chromosomes (in contrast to the opinion of Sotelo and Wettstein, 1964). Although the positive heteropycnotic X-chromosome in the germ cells of the male cricket is very similar to the DNA body of the female (Fig. 8), there is no regular contact between sex chromosome and nucleolus neither in spermatogonia nor in spermatocytes (Figs. 9, 14). In all probability, the site of the nucleolar organizer is autosomal. — It is suggested that the amplification of the nucleolar genes in Gryllus oocytes results in an accumulation of ribosomal RNA for use during the early cleavage stages of the embryo
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    Chromosoma 26 (1969), S. 169-187 
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    Notes: Abstract A conspicuous mass of extrachromosomal DNA (Giardina's body) is found in oogonia and oocytes of Dytiscid water beetles. Since in older oocytes this DNA is associated with numerous nucleoli, it seemed probable that the ovary might contain extra copies of the genes for ribosomal RNA (rRNA). This hypothesis has been confirmed by centrifugation and molecular hybridization studies. —In Dytiscus marginalis and Colymbetes fuscus a high density satellite DNA is found in somatic cells and in sperm. Hybridization experiments show that all of the rDNA, i.e., those sequences complementary to rRNA, are located in this satellite, although quantitatively they make up only a small fraction of the satellite. In both species the DNA isolated from ovariole tips is enriched with respect to the satellite. A parallel enrichment of the rDNA has been shown in ovariole tips of Colymbetes, but for technical reasons has not been examined in Dytiscus. —The following model is proposed. In somatic cells and sperm the rDNA is part of an extensive region of high density DNA in one or more chromosomes. In oogonia and oocytes the entire high density region is replicated extrachromosomally and appears cytologically as Giardina's body.
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  • 76
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    Notes: Abstract Chromosome measurements were performed in four species of snakes related at the level of suborder (Boa constrictor amarali, Xenodon merremii, Philodryas patagoniensis, Bothrops jararaca). The data obtained point out that pairs 1–3 were common to the four snakes and probably inherited from the ancestor of the suborder Serpentes. Pairs 5–8-W were characteristic of each snake; hence, it is possible to assume that they followed evolving after the appearing of the suborder Serpentes. Z-chromosomes were metacentric in B. constrictor amarali, X. merremii and B. jararaca and slightly submetacentric in P. patagoniensis. Area of these chromosomes varied from 8.6–10.6% of the haploid set in the four species studied.-The study of chromosome replication at the end of the S period points out that “shared chromosomes” have similar patterns of labeling. Therefore, it is proposed that the distribution of late replicating regions and heterochromatin in the genome is phylogenetically transmitted and probably genetically determined.—The analysis of the ending-sequence of chromosome replication shows that sex chromosomes finish earlier than macroautosomes. It is concluded that snakes probably have no mechanism of sex chromosome heterochromatinization in either sex. The absence of late replicating Z-chromosome in the males, favours the hypothesis that no mechanism of sex dosage compensation is acting in the suborder Serpentes.
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    Chromosoma 26 (1969), S. 201-207 
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    Description / Table of Contents: Zusammenfassung Es wird über Messungen des linearen Dichroismus in den Chromomerenscheiben der Riesenchromosomen von Chironomus thummi mit einem Mikrospektralphotometer für Messungen mit polarisiertem Licht berichtet. Die Meßfläche betrug etwa 2 μm im Durchmesser. Die Ergebnisse zeigen, daß eine einheitliche Orientierung der DNS in den Chromomerenscheiben nicht vorhanden ist. Die Ergebnisse werden im Zusammenhang mit den in der Literatur erhobenen Befunden über die Orientierung der DNS-Moleküle in den Chromomerenscheiben diskutiert.
    Notes: Abstract Measurements of linear dichroism in the chromomeric bands of giant chromosomes of Chironomus thummi are reported. The measurements were performed by means of a microspectrophotometer specially designed for measuring with polarized light. The diameter of the measuring area was about 2 μm. As was revealed by the results there exists no uniform orientation of the nucleic acid molecules within the chromomeric disks. The results are discussed in connection with the findings stated in literature on the orientation of the nucleic acid molecules in the chromomeric bands.
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    Chromosoma 26 (1969), S. 254-258 
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    Notes: Abstract Freshly removed testis tubules are treated with hypotonic citrate solution and fixed in 3∶1 acetic alcohol without undue rupture. The material is transferred to 60% acetic acid and the resulting suspension is air-dried onto warm slides using a micropipette. Finally the slides are stained with lacto-acetic orcein. — Provided suitable storage is made, slides need not be prepared in the same week as fixation and this may facilitate the collection of material during field study.
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  • 79
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    Notes: Abstract A description is given of the puffing sequences of the giant polytene chromosomes from the footpads of Sarcophaga bullata, from Day 3 to Day 12 of pupation at 25° C. The chromosome puffing patterns are seen to be very precise and to occur in orderly sequence with respect to general developmental events. Particular puffs appear or regress in a continuous, orderly sequence. A few puffs remain throughout adult development. Most are puffed for a limited time only. In several cases puffed regions appear to “move along” the chromosome, suggesting sequential activity of adjacent genetic loci. Attempts are made to correlate chromosome puffing with specific cellular activities — cell growth, the sequential secretion of six cuticular layers (determined by electron microscopy), cuticle sclerotization and melanization, and eventual cell death. Preliminary observation of thoracic trichogen cell chromosomes show interesting similarities and differences in puffing patterns, when compared with footpad sequences.
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  • 80
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    Notes: Abstract The diploid chromosome number of two species of sidenecked turtles (Podocnemis unifilis and P. expansa) was found to be 28. Under normal culture conditions, half of the chromosomes of P. unifilis consistently show one or two clear secondary constrictions. In P. expansa, the incidence of cells with chromosomes bearing secondary constrictions and the number of such chromosomes per cell are less. Cells of two P. unifilis cell lines maintained a normal diploid karyotype for two years following their initiation. Then one cell line shifted to a hypodiploid mode of 27 and half of the population of the second line became pseudodiploid, the other half remaining diploid. A single six-month-old cell line from P. expansa has maintained a normal diploid mode through 10 passages.
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  • 81
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    Notes: Abstract The trichogen cell polytene chromosome maps for the Australian sheep blowfly Lucilia cuprina dorsalis R.-D. are presented. Correlations between the autosomal linkage groups and the polytene and mitotic chromosomes were accomplished using autosome-autosome and sex chromosome-autosome translocations. It is suggested that the sex chromosomes are largely inert.
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    Chromosoma 26 (1969), S. 259-269 
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    Notes: Abstract Both 6x Verbena aubletia (n=15) and 2x V. tenuisecta (n=5) form bivalents during meiosis, however, their 4x F1 hybrid (V. aubletia × V. tenuisecta) shows almost complete homoeologous pairing involving on average 19.74 out of its 20 chromosomes. In 10% cells there are 4IV+2II indicating that essentially there may be 4 homoeologous sets of 5 chromosomes each in the F1 hybrid. Evidently, V. aubletia is segmental allo-hexaploid involving 3 homoeologous genomes (A1A1 A2A2 A3A3). Whether its cytologically diploid behaviour is the result of a multivalent suppressor system or due to an acute property of preferential pairing, cannot be answered with certainty. In either case intergenomal homoeologies are totally suppressed resulting in bivalent pairing, meiotic isolation of the 3 genomes and institution of normal fertility.
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  • 83
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    Chromosoma 26 (1969), S. 270-286 
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    Notes: Abstract A plant of Agave stricta Salm. (2n=60) has a bimodal complement of 10 L, 4 M and 46 S chromosomes. It is heterozygous for a paracentric inversion which involves the middle third of the long arm of one of the L chromosomes. It produces at anaphase I bridges and fragments and also loops and fragments, both single and double. Breakage and reunion at the sub-chromatid and at the chromatid level produce side-arm bridges and bridges and fragments respectively at anaphase I. A method is given, based on chiasma frequency, which will in certain cases of inversion heterozygosity provide a reasonable estimate of the position and the length in genetic map units of an inverted segment with respect to the whole chromatid arm.
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  • 84
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    Chromosoma 26 (1969), S. 287-297 
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    Notes: Abstract The production of a gregarization pheromone has been postulated in locusts, with effects on melanization of the hopper cuticle and increased chiasma frequency during meiosis in the adult on crowding or gregarization. Lack of chiasma-inducing effect of the pheromone on albino strains is correlated with the absence or deficiency of some of the products of the metabolic pathways of tyrosine. Some of these products, commercially obtainable, are the amino acids phenylalanine and tyrosine leading to both the melanization and sclerotization pathways; dopamine formed from dopa in the lastnamed pathway; three products of dopamine i.e. protocatechuic acid, noradrenaline and adrenaline. The injection of solutions of these metabolites into the haemolymph of solitary hoppers has shown that only dopa to some extent but noradrenaline to a large extent are effective in raising chiasma frequency in solitarised individuals of normal-coloured strains of Locusta, while in two albino strains, which differ genetically, the injection of dopa, dopamine, protocatechuic acid and noradrenaline proved effective; phenylalanine was effective in only one of these albino strains, while adrenaline was effective in neither. The chiasma-inducing effect of noradrenaline, common to the three strains, is accompanied in the normal-coloured strain by a greater retention of dark coloration during solitarization and by some attainment of the crowded type of morphometric ratios which is a third physical criterion of gregarization. The genetic blocks to the physical criteria of gregaria in the albino strains lie at the immediate level of dopa production or previous to this reaction; it may be construed that such a block in the solitaria of normal-coloured strains also lies at this early level, in this case being induced by too low a pheromone concentration.
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    Chromosoma 26 (1969), S. 298-311 
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    Notes: Abstract Autoradiographs show that tritiated leucine is incorporated into protein continually at an almost linear rate during meiotic prophase of lily microsporocytes in in vitro culture. Although label is mostly in the cytoplasm for the first hour, it becomes almost evenly distributed throughout the cell after a few hours. The amount of label decreases slightly, if at all, during a chase period extending through the rest of the prophase — a period of 3 to 4 days. — The incorporation of label was blocked by 95% by the protein inhibitor, cycloheximide, at a concentration of 3.5 × 10-6 M. In the presence of this inhibitor, meiosis was arrested at all stages through metaphase I and even later. After temporary inhibition, however, or in low drug concentrations, characteristic cytological abnormalities subsequently developed, depending on the meiotic stage at which the inhibition occurred. One important observation was that the formation of chiasmata between homologs could be blocked if the inhibition was applied during the late zygotene or early pachytene stages.
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    Chromosoma 26 (1969), S. 312-325 
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    Notes: Abstract Variations in the amounts of nuclear RNA present during interphase in Vicia faba were studied by microphotometric, autoradiographic and chemical methods. In one series of experiments, nucleic acid estimations were carried out on root meristem nuclei isolated from cells which had been partially synchronized by treatment with 5-aminouracil at 20 and 25° C. In a second series, root meristem nuclei isolated from untreated plants growing at 4, 20 and 25° C, were separated into fractions, containing different interphase stages, by sucrose density gradient centrifugation. — The results from the two series suggest that at 4 and 20° C there is a net increase in the amount of nuclear RNA during interphase which parallels the net increase in DNA. At 25° C, however, there is less RNA per nucleus and this remains at the same level throughout interphase resulting in an average increase in the DNA∶RNA ratio of 55%. — It is suggested that the balance between the synthesis and release of nuclear RNA may change not only within plants, at different stages of interphase, but also between plants according to the temperature at which they are grown.
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    Chromosoma 26 (1969), S. 326-336 
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    Notes: Abstract Relative amounts of DNA were determined on telophase nuclei by Feulgen cytophotometry for euploid taxa of birch (Betula) with somatic chromosome numbers of 28, 42, 56, 70, and 84. A direct correlation was found between observed DNA absorbance and chromosome number except for plants of B. papyrifera with 84 somatic chromosomes. The DNA density value for nuclei of the 84-chromosome plants fitted a 1∶2.25 ratio instead of the expected 1∶3.0 ratio. The DNA density value for these plants was calculated to be approximately equivalent to plants which would possess 63 somatic chromosomes. The average DNA value per chromosome was 2.73 for the 84-chromosome plants in contrast to 3.50 per chromosome in each of the lower euploids. Nuclear diameters of the 84-chromosome plants were directly related to chromosome number and not to DNA density value. The genomic number of Betula was considered to be x=7, rather than x=14, since a DNA value equivalent to 63 chromosomes is a multiple of 7 and not 14. Diploid birch species (2n=2x=28), therefore, would actually be tetraploids (2n=4x=28). The reduction in DNA content may be an adaptation for the establishment of higher ploidy in birches.
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    Chromosoma 26 (1969), S. 388-394 
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    Notes: Abstract The karyotypes of four passerine bird species are described: Robin (Turdus migratorius), family Turdidae; Brown Thrasher (Toxostoma rufum), family Mimidae; Blue Jay (Cyanocitta cristata), and Common Crow (Corvus brachyrhynchos), both family Corvidae. Diploid numbers and chromosome morphology of related species previously studied are compared with the results of the present study. Karyotypes of all the studied species have considerable similarities in the whole appearance and size grouping of the chromosomes within the karyotype, but detailed morphological analysis shows a clear difference between the karyotypes of the different species.
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    Chromosoma 26 (1969), S. 355-364 
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    Notes: Abstract Following specific incorporation of tritiated thymidine into the DNA of the macronucleus of Paramecium aurelia for varying periods of time the vast majority of silver grains in electron microscope autoradiographs are associated with the area containing the small bodies and matrix. At best only 5% of the silver grains overlying the macronucleus are attributable to the large bodies. This is consistent with the view that the large bodies are the nucleoli of the macronucleus.
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    Chromosoma 26 (1969), S. 365-387 
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    Notes: Abstract Lampbrush chromosomes isolated from the germinal vesicle of medium sized oocytes can be individually identified by differences in two characters: (1) chromosome regions rich in well developed loops, and (2) number and position of spheres. Actually the lateral loops are not all equally extended, but those which are inserted in a certain region of the axis of some chromosomes are more developed and sometimes are loaded with dense and copious matrix; chiasmata do not occur inside these regions. One or more spheres are present on eight chromosomes in the complement (chromosomes I–VI, VIII and X): the total number of spheres inserted on S. salamandra lampbrush chromosomes is the highest among the salamandrid species studied so far. These landmarks as well as the maximally developed normal loops are schematically drawn on the maps of the single lampbrush chromosomes. The length of the maps corresponds to the mean value of the lengths of each chromosome relative to that of chromosome XII, taken as 100 units long. Also bivalents from first metaphase spermatocytes have been analysed: they are generally ring-shaped with two terminal or subterminal chiasmata.
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  • 91
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    Description / Table of Contents: Zusammenfassung 1. In Nierenepithelzellkulturen von weiblichen Microtus agrestis wurde die Verteilung des chromosomalen Materials auf die Tochterkerne multipolarer Mitosen untersucht. Die Anzahl der von den Geschlechtschromosomen gebildeten Chromozentren pro Zellkern sowie photometrische Messungen der Feulgen-DNS wurden für die Bestimmung der Ploidie der Kerne benutzt. Durch Pulsmarkierung mit 3H-Thymidin wurden die Markierungsmuster von Kernen in der S-Periode ermittelt. 2. 3,55% aller Mitosen zeigen eine multipolare Spindelanordnung, davon 94% in tripolarer Form. DNS-Messungen an 21 tripolaren Mitosen ergaben 5mal einen diploiden (4c), 16mal einen tetraploiden (8c) Gesamtwert. 3. Der DNS-Gehalt der Tochterkerne tripolarer Mitosen (Ana-, Telo- und Rekonstruktionsphase) mit diploidem Gesamtwert entspricht einer Aufteilung in 1 diploiden und 2 haploide Kerne. Tripolare Mitosen tetraploider Zellen liefern vermutlich tetraploide, triploide, diploide und haploide Tochterkerne, und zwar 2mal im Verhältnis 4∶3∶1 und 6mal im Verhältnis 3∶3∶2. In diesen Fällen zeigen die Tochterkerne das gleiche Markierungsmuster (4–9 Std nach Pulsmarkierung). 4. In 2 Fällen, in denen der Gesamt-DNS-Gehalt tripolarer Mitosen abweichend von 4 c oder 8 c ist, ergibt die Auroradiographie eine ungleiche Markierung der Tochterchromosomengruppen. 5. Interphasenkerne mit 1 Chromozentrum bzw. 3 Chromozentren fallen in DNS-Verteilungskurven in den haploiden (1c) bzw. triploiden (3c) Bereich. Während vermutlich haploide Kerne nur vereinzelt zu finden sind, sind vermutlich triploide Kerne nicht allzu selten; sie liegen in den Präparaten meist paarweise nebeneinander und stimmen im DNS-Gehalt stets überein. Vermutlich triploide Kerne sind zur DNS Synthese fähig. Haploide Kerne in der S-Periode wurden nicht gefunden. 6. Unsere Befunde sprechen gegen eine zufällige Verteilung der Chromosomen auf die Tochterkerne multipolarer Mitosen. Sie legen vielmehr eine Sortierung und Aufteilung in komplette haploide Sätze oder Vielfache des haploiden Satzes nahe. 7. Die Möglichkeiten der somatischen Segregation homologer Chromosomen bei multipolaren Mitosen werden diskutiert. 8. Multipolare Mitosen entstehen häufiger in polyploiden Zellen als in diploiden. Die Möglichkeit der Entstehung polyploider Zellen durch Zellverschmelzung und synchrone Mitose der Kerne mehrkerniger Zellen weist auf die Ausbildung multipolarer Spindeln in Zellen mit einem Überschuß an Zentriolen hin.
    Notes: Abstract In kidney epithelial cultures from female Microtus agrestis, 3,55% of all mitoses are multipolar, 94% of them tripolar. Feulgen photometric measurements of 21 tripolar mitoses reveal a total DNA amount corresponding to the mitotic diploid value (4c) in 5 cases, and to the tetraploid value (8c) in 16 cases, Diploid tripolar mitoses divide into one daughter nucleus with a diploid DNA value (2c) and two nuclei each with a haploid DNA value (1c). Most tetraploid tripolar mitoses divide into one daughter nucleus with a diploid DNA value (2c) and two nuclei with a triploid DNA value (3c). Also the sex chromosomes are distributed to the daughter nuclei in the relation of 2∶3∶3. This can be seen in anaphase figures as well as in interphase nuclei presumably derived from tripolar mitoses, showing chromocenters according to the number of X-chromosomes. In two cases of tripolar tetraploid mitoses the resulting nuclei have a haploid, a triploid and a tetraploid DNA value. The DNA replication pattern is always identical in the daughter nuclei of diploid and tetraploid tripolar mitoses. — Our observations suggest segregation and distribution of haploid chromosome sets or multiples of haploid sets to the daughter nuclei of multipolar mitoses. They also show a possible way of formation of haploid and triploid cells in a basically diploid tissue. Presumably triploid nuclei (with 3 chromocenters) are capable of DNA synthesis.
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  • 92
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    Notes: Abstract When the fourth chromosome of Drosophila melanogaster is attached, as the result of an induced translocation, to 21A in 2L or 60E in 2R, its tip exhibits a marked capacity to pair end-to-end with the tips of the other chromosomes. In each of the translocations, about 59 per cent of the contacts involving the tip of 4 were with the tip of X. If this pairing preference reflects structural similarity, the tip of 4 is much more like the tip of X than that of any other chromosome. The significance of this phenomenon is discussed with respect to the standard pattern of end-to-end association in the Oregon-R wild-type stock that provided the control preparations. In the 4-2L rearrangement, the interaction of chromosome 4 with the tip of 2L (101E with 21A) led to pronounced puffing in subdivisions 21A and B, as was most strikingly manifested when the distal segments of 2L failed to synapse and the homologue of paternal origin showed a large puff whereas that of maternal origin (not carrying the fourth chromosome) remained unpuffed.
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    Chromosoma 26 (1969), S. 427-448 
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    Notes: Abstract A fine structural analysis of apolar mitosis induced by chloral hydrate was made on Haemanthus katherinae Bak. endosperm. Under the influence of chloral hydrate MTs disappear initially and then are formed de novo. Kinetochore fibers grow away from kinetochores and their formation is asynchronous for all chromosomes in the set and also for sister kinetochores. Bundles of MTs forming kinetochore fibers converge toward one of the poorly defined polar regions during formation of kinetochore fibers (metaphase) and in motionless kinetochores. Such MTs increasingly diverge when kinetochores move during anaphase. The relation of ER to formation of MTs is evident and briefly discussed. A continuous transition exists between NE and ER during formation and disintegration of the NE. Some theoretical aspects of these problems were also discussed.
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  • 94
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    Notes: Abstract Cytological studies on telophase and early prophase in roottip cells of several plant species (Allium cepa, 2n=16; four Crepis species, including Crepis capillaris, 2n=6; Callitriche hermaphroditica, 2n=6; Nigella arvensis, 2n=12; Secale cereale, 2n=14) revealed that chromosome ends are attached two by two forming chains of chromosomes (interphase associations). In these chains homologous chromosomes are presumably located adjacent to each other. In Crepis capillaris it was observed that the two nucleolar chromosomes form a separate ring one end attached to the ring of the four remaining chromosomes and the other end attached to the nucleolus. It is proposed that these end-to-end attachments have significance for chromosome pairing in meiosis. The adjacent location of homologous chromosomes in the interphase associations would facilitate rapid and regular synapsis.
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    Chromosoma 26 (1969), S. 449-468 
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    Notes: Abstract Seeds of Plantago insularis Eastw. which were irradiated with gamma rays yielded 37–67% semi-sterile plants. Twenty-four out of sixty-four of these plants were heterozygous for one or more chromosomal rearrangements. Twothirds of these were translocations, and one-third were inversions. Homozygous lines for four translocations were established. The karyotypes of these provide chromosome markers either at pachynema or in mitotic divisions, or both. Breakage positions were usually located within hetrochromatic segments or at the ends of heterochromatic regions (72.6% of all breaks), and half of all breaks occurred at the juncture of the centromere with the proximal heterochromatin. The consequences of proximal breakage were non-random, in that 93% of such breaks resulted in translocations and only 7% in inversions, whereas more than half of breaks in non-centromeric regions became involved in inversions. The individual chromosomes differed in the types of breakage and of aberrations produced, and these differences appeared correlated with length ratios of heterochromatic segments flanking the centromeres.
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    Notes: Abstract The intrachromatidal distributions of achromatic lesions (AL) and chromatid breaks (B′) on 10 sections of equal length of the chromatids from the centromere to the distal end are investigated. Formally they can be described by Poisson-distributions. The maximum of the frequencies of AL and B′ is located in the distal half of the chromatids. The distributions are interpreted with restitutional action.
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    Chromosoma 26 (1969), S. 469-474 
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    Notes: Abstract Experiments were carried out to study if chromatid breaks induced by nitrosoguanidine in combination with some known radiomimetics and X-rays interact with each other. It has been seen that nitrosoguanidine induced breaks exhibit full interaction in production of isochromatid breaks and interchanges with diepoxybutane, ethylmethane sulfonate and ethyleneimine but fail to do so with X-rays though the effects were additive. This has been interpreted to indicate that nitrosoguanidine produced aberrations have both, temporal and qualitative similarities with those of diepoxybutane, ethylmethane sulfonate and ethyleneimine and not with those induced by X-rays.
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    Chromosoma 27 (1969), S. 1-19 
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    Notes: Abstract The study of mitotically unstable B-chromosomes (supernumeraries) of two grasshopper species confirmed a suggestion made earlier (Nur, 1963) that the instability should always be associated with a tendency of the B's to increase in frequency. Among 780 Camnula pellucida (Scudder) males from California, 105 had B's. In the testes of these males the number of B's varied from follicle to follicle and ranged between 0 and 4. Because of this variation, the number with which each male started to develop could not be determined. However, the relatively low frequency of males with B's and the regular meiotic behavior of the latter suggested that most of the 105 males started with a single B. Cytological analysis of the cells of the gastric caeca of 31 males whose testes contained B's confirmed this suggestion by showing that only one male had two B's in these cells; all the rest had one. In the testes of the 74 other males the mean number of B's ranged from 0.89–2.50, but only two males had means higher than 2.00. The observed ratio of one male with two B's to 30 with one, suggested that only the two males with the highest means started to develop with two B's and that the other 72 males all started with one. Since the mean for the 72 males was 1.37 B's per male, it was concluded that during the development of the testes of these males the mean increased by 37%. The males with B's had fewer follicles in their testes and apparently had also a lower frequency of normal sperm. — The analysis of the testes of Locusta migratoria L. males from Japan gave results which agreed with those from C. pellucida.
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    Chromosoma 27 (1969), S. 86-94 
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    Notes: Abstract In this paper the Authors decribe the karyogram of three species of Scincidae (Chalcides chalcides chalcides, Chalcides ocellatus tiligugu, and Mabuya striata). The diploid number of these species is 2n=28. It is not possible to subdivide the chromosome set in micro- and macrochromosomes or to recognize the heterochromosomes morphologically. Ch. ocellatus and M. striata have very similar karyograms; that of Ch. ch. chalcides is different in that chromosomes 6, 7, 8, 9, and 10 are acrocentric. Pericentric inversion is probably involved in the karyotypic evolution of these species.
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    Chromosoma 27 (1969), S. 64-85 
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    Notes: Abstract The autosomal salivary gland chromosome puffing patterns of Drosophila simulans are described and compared with the puffing patterns of the sibling species D. melanogaster. During the late third larval instar and the prepupal period the patterns of puffing activity of these two species are similar — approximately 50% of the puffs common to both species showing identical activities. The remaining puffs differ in their timing of activity, or in their mean sizes, or in both of these parameters. A number of puffs (14) found in D. simulans have not been regularly observed in the Oregon stock of D. melanogaster but are active in other D. melanogaster strains. One puff (46 A) of D. melanogaster was absent from D. simulans and forms a heterozygous puff in hybrids, when the homologous chromosomes are synapsed. When the homologues are asynapsed a puff at 46 A is restricted to the melanogaster homologue. The puff at 63E on chromosome arm 3L is considerably smaller in D. simulans than in D. melanogaster and this size difference is autonomous in hybrids. Other puffs not common to both species behave non-autonomously in the species hybrid, even when the homologous chromosomes are asynapsed.
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