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  • 1995-1999  (10)
  • 1970-1974  (4)
  • 1965-1969  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    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.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 8-15 
    ISSN: 1432-0827
    Keywords: Insulin ; Bone ; Calcium ; Resorption ; Orthophosphate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'administration d'insuline cristallisée à des rats thyroparathyroidectomisés provoque une augmentation de la calcémie et de la phosphorémie. Le calcium plasmatique s'élève de façon linéaire entre 31 et 250 m Unités d'insuline/100 g de poids corporel. La courbe obtenue n'est guère différente de celle obtenue par extrait parathyroidien. L'administration simultanée d'insuline et d'extrait parathyroidien à des rats thyro-parathyroidectomisés agit sur la calcémie et la phosphorémie par un effet additif. Lorsque des os frontaux d'embryons de poulet sont cultivésin vitro en présence d'insuline cristallisée, le taux de résorption augmente. L'insuline augmente le taux de consommation en glucose des explants et induit une accumulation de citrate dans le milieu de culture. L'insuline stimule donc la résorption osseuse.
    Abstract: Zusammenfassung Der Plasmagehalt an Calcium und Phosphor bei thyroparathyreoidektomierten Ratten wurde durch die Verabreichung von kristallinem Insulin erhöht. Das Plasmacalcium verhielt sich zwischen 31 und 250 m Einheiten Insulin pro 100 g Körpergewicht linear. Die Steigung der erhaltenen Kurve ist nicht signifikant verschieden von derjenigen, die nach Parathyreoidea-Extrakt erhalten wird. Die gleichzeitige Verabreichung von Insulin und Parathyreoidea-Extrakt von thyroparathyreoidektomierten Ratten hatte eine kumulative Wirkung auf den Gehalt von Calcium und Phosphor im Plasma. Wenn Stirnbeine von Kükenembryos mit kristallinem Insulinin vitro kultiviert wurden, erhöhte sich die Resorptionsrate. Das Insulin steigerte den Glucoseverbrauch der Explantate und verursachte eine Anreicherung von Citrat im Kulturmedium. Die Ergebnisse deuten auf eine Stimulation der Knochenresorption durch Insulin.
    Notes: Abstract the administration of crystalline insulin to thyroparathyroidectomized rats raised their calcium and phosphorus plasma levels. The plasma calcium gave a linear response between 31 and 250 mU of insulin/100 g body weight. The slope obtained is not significantly different from that obtained with parathyroid extract. The simultaneous administration of insulin and parathyroid extract to thyroparathyroidectomized rats affected the calcium and phosphorus plasma levels in an additive fashion. When chick embryo frontal bones were cultivatedin vitro with crystalline insulin the rate of resorption increased. Insulin increased the rate of glucose consumption by the explants and induced the accumulation of citrate in the culture medium. It is concluded that insulin stimulates bone resorption.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 6 (1970), S. 133-142 
    ISSN: 1432-0827
    Keywords: Testosterone ; Dehydroepiandrosterone ; Glucosephosphate-dehydrogenase ; Glucose ; Bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les effets des androgènes (déhydroépiandrostérone et testostérone) sur le métabolisme des hydrates de carbone ont été étudiés en utilisant deux modèles expérimentaux. Le premier fait appel à la culturein vitro d'os embryonnaires d'oiseaux. Dans le deuxième modèle, on utilise des os non embryonnaires de mammifères, en cours d'ossification enchondralein vivo. Dans les deux cas, on note une augmentation de l'activité de la glucose-6-phosphate déhydrogénase et une oxydation différente de la glucose-1-14C et glucose-6-14C. Ces faits indiquent un changement dans le métabolisme du glucose allant vers la voie oxydative directe. En plus, le traitement provoque une hyperplasie de la couche hypertrophique dans l'épiphyse osseuse chez les souris prépubères.
    Abstract: Zusammenfassung Es wurden die Wirkungen von Androgenen (Dehydroepiandrosteron und Testosteron) auf den Kohlenhydratumsatz von Knochen mittels 2 experimenteller Modelle untersucht: einerseits anin vitro gezüchteten Bindegewebsknochen von Hühnerembryonen und andererseitsin vivo an nichtembryonalen Säugetierknochen mit endochondraler Ossifikation. In beiden Modellen läßt die Aktivitätszunahme der Glucose-6-phosphat-dehydrogenase und die unterschiedliche Oxydation von Glucose-1-14C und Glucose-6-14C eine Verschiebung des Glucosemetabolismus gegen den direkten oxydativen Abbau vermuten. Weiterhin erzeugt eine Behandlung mit diesen Hormonen eine Hyperplasie der hypertrophen Zellschicht an der Epiphysenplatte von vorpubertären Mäusen.
    Notes: Abstract An investigation on the effects of androgens (dehydroepiandrosterone and testosterone) on the carbohydrate metabolism of bone was carried out with two experimental models: avian embryonic membranous bone cultivatedin vitro, and mammal non-embryonic bone of endochondral ossificationin vivo. In both models, the increase in glucose-6-phosphate dehydrogenase activity and the differential oxidation of glucose-1-14C and glucose-6-14C suggest a shift in glucose metabolism toward the direct oxidative pathway. In addition, treatment with these hormones produces hyperplasia of the hypertrophic cell layer at the epiphyseal plate of prepubertal mice.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1573-675X
    Keywords: Apoptosis ; CD95 (Fas/APO-1) ; NF-κB/Rel ; T lymphocytes.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The activity of NF-κB/Rel transcription factors can inhibit the apoptosis induced by TNF, UV or cancer therapy drugs in a number of cell types, including human T lymphocytes. Furthermore, the NF-κB/Rel inducer, phorbol-12-myristate-13-acetate (PMA), has been reported to suppress the CD95-induced apoptosis of human T lymphocytes. To verify whether the survival-enhancing effect of PMA required NF-κB/Rel activity, we generated two Jurkat cell sublines (AL.7 and AL.8) transfected with a pCMV4-IκBα construct, and two (AL.3 and AL.5) with the void pCMV4 vector. Compared to wild type, AL.3 and AL.5 cells, the AL.7 and AL.8 sublines displayed markedly lower amounts of NF-κB/Rel nuclear complexes and a reduced expression of a κB-controlled CAT reporter gene after 1 and 4 h of incubation with PMA, respectively. All the five cell types displayed negligible levels of apoptosis when cultured with medium or PMA alone; when stimulated with the mAb CH-11, the AL.7 and AL.8 sublines displayed apoptotic responses only slightly (〈0.5 fold) higher than control cells. On the other hand, the salvage activity of PMA was partially impaired in the AL.7 and AL.8 sublines. PMA inhibited apoptosis by 〉85% in wild type, AL.3 and AL.5 cells and by 〈60% in the AL.7 and AL.8 sublines; the apoptosis percentages in the mAb CH-11 + PMA cultures of the IκBα-transfected cells were 〉4-fold higher than in control cells. We conclude that the inhibition of the CD95-induced apoptosis by PMA relies on both NF-κB/Rel-dependent and -independent mechanisms. The partial contribution of these nuclear factors to the suppression of apoptosis indicates that the NF-κB/Rel activity can influence the extent of the CD95-induced T cell death.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 2 (1968), S. 133-144 
    ISSN: 1432-0827
    Keywords: Dehydroepiandrosterone ; Testosterone ; Embryo ; Tissue culture ; Frontal bone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les os frontaux d'embryons de poulet, de 12 jours de développement, cultivés sur coagulum de plasma avec sulfate de déhydroépiandrostérone (DS) en concentration 1 mM, montrent hyperplasie du périoste et synthèse augmentée du matrice osseuse. Ces phénomenes ne son pas vus quand on emploie les os frontaux de 11 jours de développement. La testostérone produit les mêmes effets que le DS. Le deux steroïdes semblent agir directement sur l'os selon on peut le déduire des conditions expérimentales. L'activité de la phosphatase alcaline des frontaux d'embryons de poulet de 12 jours de développement est augmentée de manière significative quand les rudiments son cultivés dans un milieu qui contient DS ou testostérone. Dans ces deux cas: a) on peut révéler l'activation de l'enzyme par des expériences de cinétique enzymatique et b) les vélocités maximes apparantes ont une grande correlation avec le logarithme des doses employées. Quand les deux steroïdes son essayés en conditions semblables, les deux produisent la même augmentation de l'activité phosphatasique.
    Abstract: Zusammenfassung Wenn Stirnknochen von 12 Tage alten Hühnerembryonen in vitro auf koaguliertem Plasma mit Zusatz von 1 mM Dehydroepiandrosteronsulfat gezüchtet werden, so zeigen sie eine Hyperplasie des Periostes und eine erhöhte Synthese des Osteoidgewebes. Diese Erscheinung trifft nicht zu, ween 11 tägige Stirnknochen in gleicher Weise gezüchtet werden. Mit Testosteron werden gleiche Effekte wie mit Dehydroepiandrosteronsulfat erzielt. Aus den gewählten Versuchsverhältnissen kann abgeleitet werden, daß beide Steroide direkt auf den Knochen zu wirken scheinen. Die Aktivität der alkalischen Phosphatase im Stirnknochen des 12 Tage alten Hühnerembryos ist signifikant erhöht, wenn die Knochenansätze in einem Dehydroepiandrosteron oder Testosteron enthaltenden Medium gezüchtet werden. In beiden Fällen ergeben enzymkinetische Untersuchungen einerseits eine Aktivierung des Enzyms, andererseits eine gute Korrelation der erhaltenen scheinbaren Maximalgeschwindigkeiten mit dem Logarithmus der verwendeten Dosen. Bei gleichzeitiger Prüfung bewirkten beide Steroide gleichzeitig eine ähnliche Aktivitätszunahme der alkalischen Phosphatase.
    Notes: Abstract Chick embryo frontal bones at 12 days of development, cultivated in vitro on plasma clots with dehydroepiandrosterone sulfate in a concentration 1mM, exhibit periosteal hyperplasia and increased synthesis of osteoid tissue. These phenomena are not observed when 11-day frontals are cultivated in similar conditions. Testosterone produces the same effects as dehydroepiandrosterone sulfate. Both steroids seem to act directly on bone as can be inferred from the experimental conditions employed. The alkaline phosphatase activity of chick embryo frontal bones at 12 days of development is significantly increased when the rudiments are cultivated in a medium containing dehydro-epiandrosterone or testosterone. In both cases a) enzyme kinetics experiments revealed that there is activation of the enzyme and b) the apparent maximum velocities obtained are hihgly correlated with the logarithm of the doses employed. When assayed simultaneously, both steroids were found equally active in promoting the increase in alkaliue phosphatase activity.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Theory of computing systems 7 (1973), S. 323-337 
    ISSN: 1433-0490
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract This paper is about the causality structure of systems in Hilbert spaces. While treatments on the subjects are usually confined to systems which enjoy properties such as linearity, boundedness, or nonpredictive behavior, here, all these properties play no essential role. As a consequence, new and more general results are obtained. These results concern the concepts of causality, anticausality, and crosscausality, and give necessary and sufficient conditions to decompose a general system into the sum of causal, anticausal, and crosscausal components.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1434-601X
    Keywords: PACS:26.20.+f Hydrostatic stellar nucleosynthesis – 25.60.Dz Interaction and reaction cross sections
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: The loss of 8Li recoil nuclei in 7Li(d,p)8Li has been measured using different backings and 7LiF target thicknesses as well as different deuteron energies. The results confirm essentially recent TRIM calculations. The losses are large (about 13%) for the combination of thin targets and heavy backings at E d=0.80 MeV and increase with decreasing deuteron energy. The implications on the cross sections for 7Li(d,p)8Li and 7Be(p,γ)8B are discussed.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1434-601X
    Keywords: 25.70-z ; 24.30.Cz ; 25.70.Lm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract γ-rays are measured in coincidence with the dissipative complex fragments from the35Cl +64Ni reaction at 7.7 A MeV. Theoretical γ-ray coincidence spectra are determined through a fitting procedure using the contribution of the excited fragment statistical γ-decay calculated by means of the CASCADE code. Whereas the expected statistical spectra fit very well the data in the energy regionE ν=2 to 8 MeV, above this energy another emission mechanism in addition to the statistical decay has to be considered in order to reproduce the experimental spectra. Simulations based on the Vlasov equation suggest that this emission could come from the decay of dipole strength excited in the intermediate dinuclear system.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Archives of environmental contamination and toxicology 35 (1998), S. 302-308 
    ISSN: 1432-0703
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Notes: Abstract. For nearly 50 years, the fingernail clam (Musculium transversum) was believed to be virtually eliminated from the Illinois River. In 1991, workers began finding substantial populations of M. transversum in the Illinois River including several beds in and around the highly polluted Chicago Sanitary District. In order to determine if populations of M. transversum from polluted sites exhibited any genetic response to the high levels of toxins and to examine the genetic structure of several populations of M. transversum for any changes due to the population crash, starch-gel electrophoresis was performed on M. transversum from three Illinois River localities and four Mississippi River basin locations. The sampled populations produced an inbreeding coefficient (FIS) of 0.929, indicating that the populations were highly inbred. The results of a suspected founder effect due to a bottleneck was suggested by an FST= 0.442. The isozyme Glucose-6-phosphate isomerase-2 (Gpi-2) produced allelic frequency patterns that were consistent with expected patterns of a pollution-tolerant allele. Polluted sites exhibited elevated frequencies of Gpi-2 100 whereas nonpolluted sites exhibited elevated frequencies of Gpi-2 74 . This frequency pattern suggested that natural selection was occurring in populations under severe toxic pressures, leading to an increase in the frequency of the allele Gpi-2 100 . Therefore, Gpi-2 100 is a possible pollution-tolerant mutation in M. transversum.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1434-601X
    Keywords: PACS: 25.70.-z Low and intermediate energy heavy-ion reactions – 24.30.Cz Giant resonances – 23.20.-g Electromagnetic transitions – 25.70.Lm Strongly damped collisions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter sets that are in good agreement with each other.
    Type of Medium: Electronic Resource
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