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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 16 (1974), S. 139-144 
    ISSN: 1432-0827
    Keywords: Dental enamel ; Iron ; Calcium ; Phosphorus ; Electron probe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract Using electron microprobe analysis, the surface layer of enamel of rat maxillary incisors was found to contain 10–30% Fe. The Ca and P concentrations in different areas of the enamel surface varied inversely with the Fe concentration. The Ca/P weight ratio was 1.8 in areas containing 10% Fe, but decreased to 1.0 in the most Fe-rich areas. The Fe concentration was highest at the prism boundaries, whereas the maximum concentrations of Ca and P were found within the enamel prisms. The concentrations of Fe in rat incisor enamel are among the highest values reported for any mineralized tissue.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 15 (1974), S. 111-123 
    ISSN: 1432-0827
    Keywords: Fluoride ; Calcium ; Phosphorus ; Bone ; Periosteum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une méthode d'estimation de la surface périostée de l'os en voie de minéralisation est mise au point et appliquée à des porcs recevant 2 mg de fluorure par Kg de poids et par jour pendant 10 mois. L'adjonction de fluor intervient significativement dans le cas d'une déficience en calcium et phosphore. La surface en voie de minéralisation est nettement réduite. Lorsque le calcium et phosphore sont normaux, l'addition de fluorure augmente nettement la surface en voie de minéralisation. Le microscope électronique à balayage permet de mettre en évidence au niveau de l'os une perte de l'orientation longitudinale des fibers et des surfaces poreuses irrégulières chez les animaux soumis au floor.
    Abstract: Zusammenfassung Zur Bestimmung der verkalkenden Oberfläche des Periosts wurde eine Methode entwickelt und bei Schweinen angewandt, welche während etwa 10 Monaten 2 mg Fluorid per kg Körpergewicht und per Tag erhalten hatten. Dieses zusätzliche Fluorid hatte eine signifikante Wirkung bei Calcium- und Phosphormangel. Die verkalkende Oberfläuche ging stark zurück, während jedoch, wenn kein Calcium- und Phosphormangel bestand, das zusätzliche Fluorid die verkalkende Oberfläche vergrößerte. Beobachtungen mit dem Raster-Elektronenmikroskop am Knochen zeigten, daß die Längsorientierung der Fasern fehlte und daß Knochen von mit Fluorid gefütterten Tieren unregelmäßige, poröse Oberflächen aufwiesen.
    Notes: Abstract A method for estimating periosteal bone-mineralizing surface was developed and applied to swine fed 2 mg of fluoride/kg of body weight/day for about 10 months. Added fluoride interacted significantly with calcium and phosphorus deficiency. Mineralizing surface was greatly reduced, whereas when calcium and phosphorus were adequate, added fluoride greatly increased mineralizing surface. Scanning electron microscope observations of bone disclosed loss of longitudinal orientation of fibers and irregular porous surfaces in bone from fluoride-fed animals.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 15 (1974), S. 181-188 
    ISSN: 1432-0827
    Keywords: Biopsy ; Bone ; Calcium ; Phosphorus ; Specific gravity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The specific gravities (SG) of bone samples taken from various parts of the skeleton of cattle and sheep were determined gravimetrically in an effort to establish which sites give the most reproducible and uniform results, so that between animals, or sequential within animals, comparisons may be made with maximum sensitivity. Samples obtained from the mandible of sheep and the rib of cattle and sheep were found to be too variable to be useful for most purposes. Best results were obtained using whole bones which are easily prepared, such as the tibial tarsal bones of cattle and sheep and the fibular tarsal bone of cattle. These bones gave within animal deviations of 0.012–0.024 SG units, when comparing left bone with right bone. Slightly higher values were obtained for coccygeal vertebrae from cattle and distal metacarpal condyles from sheep. SG was related to ash, calcium and phosphorus contents of coccygeal vertebrae of cattle and it is considered that, for survey work on the mineral status of the bones of cattle and sheep, the correlations are sufficiently high to make their determination unnecessary. This will enable radiation determined SG techniques to be applied to this type of work.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 259-279 
    ISSN: 1432-0827
    Keywords: Osteocyte ; Calvarium ; Histology ; Development ; Calcium ; Phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des cartes tissulaires ainsi que les caractéristiques et propriétés cellularires ont été relevées au cours d'une étude de microscopie optique du développement de la calotte cranienne de souris, avant la naissance, jusqu'au 26ème jour. Les population d'ostéocytes de moitiés droite et gauche de ces calottes sont semblables, mais décroissent avec le temps dans un volume donné. De petites plages limitées de matrice osseuse se colorent pour le phosphate (ou carbonate) de façon plus nette que la matrice environnante, qui se colore légèrement après coupe. Les divers types ostéocytaires se distinguent par les réactions histochimiques du calcium et du phosphate, qui sont associés dans les cellules osseuses de façon complexe, variant dans le temps et la localisation. Ces deux constituants ne sont pas toujours présent dans les cellules des diverses régions, ou dans la même localisation dans un type cellulaire donné. En tenant compte des changements visible dans les divers types cellulaires avec le temps, dans des régions données, une hypothèse de “charge” et “décharge” cellulaire est émise.
    Abstract: Zusammenfassung Anläßlich einer mikroskopischen Studie über die Entwicklung des Mäuse-Calvariums von der Pränatalperiode bis zu 26 Tagen nach der Geburt wurden auch die Gewebetopographie sowie die Charakteristica und Eigenschaften der Zellen aufgezeichnet. Die Osteocyten-populationen in der linken und rechten Hälfte des Calvariums waren sich gleich, nahmen jedoch bei einem gegebenen Volumen mit der Zeit ab. Kleine isolierte Stellen von Knochen-matrix konnten leichter auf Ph sphat (oder Carbonat) angefärbt werden, als die umgebende Matrix, welche sich wohl am Schnitt, nicht aber am ganzen Stück färben ließ. Die verschiedenen Typen von Osteocyten wurden aufgrund histochemischer Calcium- und Phosphat-reaktionen bestimmt. Calcium und Phosphat waren innerhalb der Knochenzellen auf komplexe Art miteinander verbunden, die je nach Zeit und Lagerung unterschiedlich war. Zellen in abgetrennten Bereichen enthielten nicht immer Calcium und Phosphat und beide waren bei einer bestimmten Zellenart auch nicht immer am gleichen Ort abgelagert. Aufgrund der an ausgewählten Stellen beobachteten, zeitlich bedingten Veränderungen innerhalb der verschiedenen Zelltypen wird vorgeschlagen, daß es sich dabei um eine Sequenz von “Ladung” und “Entladung” der Zellen handelt.
    Notes: Abstract Tissue maps, and cell characteristics and properties were recorded in a study under the optical microscope of the development of the mouse calvarium from pre-natal to 26 days. Osteocyte populations in left and right halves of the calvarium were similar, but decreased with time for a given volume. Small isolated areas of bone matrix stained for phosphate (or carbonate) in a more readily available form from that in the surrounding matrix, which could be stained after sectioning but failed to stain in bulk. Osteocyte types were defined on the basis of histochemical methods for calcium and phosphate, which were associated inside bone cells in a complex manner, varying with time and position. The calcium and phosphate were not always present within the cell in discrete regions and were not always present in the same place in a given cell type. On the basis of a study of changes in cell types with time in selected sites a sequence of “loading” and “unloading” is proposed.
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  • 5
    ISSN: 0570-0833
    Keywords: Displacement reactions ; Phosphorus ; Phosphorus ; Reaction mechanisms ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of phosphorus(v) compounds involving the mutual interconversion of tetra- and pentacoordinate species are discussed in a critical review emphasizing stereochemical implications of the reaction mechanism. This discussion includes the formation and decomposition of the stable oxyphosphoranes, the Michaelis-Arbusov, Perkov, and Wittig reactions, interconversions of phosphines and their oxides, and the nucleophilic displacements on phosphonium compounds. Reactions of phosphate esters and related compounds receive particular attention. All chemical arguments are derived by considering the effect of factors determining the relative stabilities of phosphorane derivatives, their rates of formation, decomposition and rearrangement by bond deformation or rupture and recombination processes, considerations which are uniformly applied on the basis of concepts developed in a preceding communication[2]. It is shown that a comprehensive mechanistic interpretation of the foregoing reactions requires substantial addition to available conceptual foundations such that, in many cases, present concepts and mechanisms must be revised.
    Additional Material: 2 Ill.
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  • 6
    ISSN: 1432-0827
    Keywords: Phosphorus ; Intestine ; Absorption ; Rickets ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'autoradiographie en microscopie électronique est utilisée pour déterminer la distribution du phosphore dans les cellules d'absorption du duodénum pour déterminer si une différence existe entre le rat rachitique, le rat normal et le rat rachitique traité par vitamine D. Pas de différence notable n'est observée en répartition de phosphate entre les groupes, mais l'animal rachitique obsorbe du phosphore et tous les groupes présentent une répartition différente de celle du calcium. On note un marquage des microvillosités, de l'appareil terminal de jonction, des mitochondries, du noyau, des vesicules denses et claires, ainsi que de l'ergastoplasme lisse et rugueux.
    Abstract: Zusammenfassung Die elektronenmikroskopische Autoradiographie wurde verwendet, um die Verteilung von Phosphor in den absorbierenden Zellen des Duodenum zu bestimmen und um jeglichen Unterschied festzustellen, der zwischen rachitischen, normalen und Vitamin D-behandelten rachitischen Ratten bestehen könnte. Die Phosphatverteilung variierte nur wenig zwischen den verschiedenen Diät-Gruppen, hingegen konnte das rachitische Tier Phosphat absorbieren, und alle Gruppen zeigten eine Verteilung, welche von derjenigen des Calciums abwich. Die Markierung konnte auf den Microvilli, dem Terminalgeflecht, den Mitochondrien, dem Zellkern, den hellen und dichten “core vesicles” (=Vesikeln mit hellem und dichtem Kern) und dem glatten und rauhen endoplasmatischen Reticulum gesehen werden.
    Notes: Abstract Electron microscopic autoradiography was utilized to determine the distribution of phosphorus within the absorptive cells of the duodenum and to determine any difference that might exist between the rachitic, normal and vitamin-D-treated rachitic rat. No great difference was noted in phosphate distribution among the various nutrition groups, but the rachitic animal was able to absorb phosphorus and all groups demonstrated a distribution different from that of calcium. Label was seen over the microvilli, terminal web, mitochondria, nucleus, dense and light core vesicles, as well as smooth and rough endoplasmic reticulum.
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  • 7
    ISSN: 1432-0878
    Keywords: C cells ; Sheep ; Calcitonin ; Calcium ; Phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les recherches combinées qualitatives et quantitatives indiquent chez la Brebis, et contrairement aux résultats acquis chez la Vache, que la parturition n'est pas accompagnée d'une décharge plus ou moins intense de calcitonine. La Brebis parturiente ne montre aucune variation significative de la calcémie et de la phosphatémie; sa thyroïde renferme des taux de calcitonine analogues à ceux rencontrés chez des brebis taries, non gestantes. Dans les mêmes conditions, l'examen au microscope électronique des cellules C permet encore de rendre compte d'activités de synthèse, de sécrétion et d'excrétion tout à fait normales.
    Notes: Summary A combination of qualitative and quantitative studies show that there is not an abrupt release of calcitonin at the time of parturition in the ewe; these results differ from those obtained by several authors in the parturient cow. At lambing time, ewes are neither hypocalcemic nor hypophosphatemic; thyroidal calcitonin content is similar in parturient and in dry non-pregnant ewes. In electron microscopic studies, synthesis and release of calcitonin from C-cells in ewes, slaughtered in the hours just after lambing, appear to be as usual. These results are discussed with regard to the syndrome of parturient paresis in ruminants.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 8 (1971), S. 73-82 
    ISSN: 1432-0827
    Keywords: Bone ; Calcium ; Phosphorus ; Sodium ; Magnesium ; Electron probe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'analyse par microsonde électronique, technique récente, a été peu utilisée pour l'étude du tissu osseux. Le rapport molaire Ca/P a été mesuré pour l'os normal et certains os pathologiques. Les résultats sont en accord avec ceux obtenus par les autres méthodes, en particulier la microradiographie. La microsonde électronique permet le dosage du sodium et du magnésium, constituants secondaires de l'os, à l'échelle microscopique. Nos observations mettent en évidence l'hétérogénéité de la distribution de ces éléments: concentration élevée dans l'os jeune (ostéone), moindre dans l'os interhaversien. Ces résultats sont en accord avec l'hypothèse de Neuman de l'absorption des ions sodium et magnésium à la surface du crystal d'apatite.
    Abstract: Zusammenfassung Die Mikroanalyse mittels Elektronensonde ist eine neue Technik für die Untersuchung von Knochen; die Bedingungen für eine richtige Interpretation der Resultate werden beschrieben. Das molare Ca/P-Verhältnis wurde in normalen und in drei pathologischen Knochen gemessen. Diese Messungen wurden in verschiedenen Regionen des corticalen Knochens durch-geführt. Die Resultate stimmen mit den durch Mikroradiographie erhaltenen überein. Mikroanalysen mittels der Elektronensonde ermöglichten es, die Verteilung von Na und Mg in den zwischenhaversschen und haversschen Geweben von corticalem Knochen Erwachsener zu untersuchen. Unsere Beobachtungen zeigen die heterogene Verteilung dieser Elemente. In Übereinstimmung mit der Hypothese der Ionen-Absorption an der Oberfläche des Apatitkristalles sind die Konzentrationen in jungen Knochen (Oesteonen) höher.
    Notes: Abstract Electron probe microanalysis is a recent technique for the study of bone and the conditions for the correct interpretation of the results are described. The Ca/P molar ratio was measured in normal and in three pathological bones. These measurements were carried out in different regions of cortical bone. The results are in agreement with the results obtained by microradiography. Microprobe analysis, however, allows the measurement of elements at the microscopic level. Electron probe microanalysis was used to study the distribution of sodium and magnesium in the interhaversian and haversian tissues of adult cortical bone. Observations show the heterogeneity of distribution of these elements. Concentrations are higher in young bone (osteons), in agreement with the hypothesis of ion absorption on the surface of the apatite crystal.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 8 (1971), S. 24-35 
    ISSN: 1432-0827
    Keywords: Bone ; Cartilage ; Epiphysis ; Calcium ; Phosphorus ; Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Les électrolytes ont été analysés dans le sérum et dans les tissues en voie de minéralisation, à des stades variables de calcification, chez des poulets et des pores normaux et rachitiques. L'humidité, les cendres et les matières organiques et déssèchées ont été analysées. Il apparait que d'autres électrolytes sériques, en plus du Ca, sont modifiés au cours du rachitisme. Le Mg et le P inorganique sont modifiés de façon variable au cours de l'avitaminose D. Des changements plus importants en contenu minéral des tissus sont observés dans les stades précoces de calcification que ceux que l'on a pu constater dans le sérum à des stades similaires, ce qui suggère un effet direct de l'avitaminose sur le tissu en voie de calcification. Quant au contenu du sérum, le dépôt de Ca est plus élevé dans les tissus d'animaux rachitiques par rapport aux témoins. Ceci n'est pourtant pas le cas du Mg ou du P inorganique, indiquant une affinité préférentielle du Ca pour le tissue rachitique. L'analyse gravimétrique de matières organiques et déssèchées des zones épiphysaires montre que les quantités de cartilage hypertrophique et en voie de dévelopment augmentent dans le cas de rachitisme, alors que le cartilage calcifié diminue, confirmant les observations histologiques antérieures. De manière inattendue, la proportion de cartilage au repos augmente au cours du rachitisme.
    Abstract: Zusammenfassung Die Elektrolyte im Serum und in mineralisierenden Geweben wurden zu verschiedenen Zeitpunkten der Verkalkung bei normalen Hühnern und Schweinen und bei solchen mit Vitamin D-Mangel analysiert. Wassergehalt, Asche, trockene und organische Substanz wurden ebenfalls gemessen. Die Ergebnisse zeigten, daß außer Ca auch andere Elektrolyte bei Rachitis verändert wurden. Mg und anorganischer P wurden durch den Vitaminmangel bei den beiden Gattungen verschiedenartig beeinflußt. In den Geweben wurde in den frühen Phasen der Verkalkung eine größere Änderung des Mineral-Spiegels gefunden, als dies zu übereinstimmenden Zeiten im Serum der Fall war, was auf eine direkte Wirkung des Vitaminmangels auf das verkalkende Gewebe schließen läßt. Im Verhältnis zum Serumspiegel wurde Ca in den Geweben der rachitischen Tiere zu einem größeren Grade als normal abgeschieden. Dies war nicht der Fall bei Mg oder anorganischem P, was einen Vorzug für Ca in den rachitischen Geweben anzeigt. Gravimetrische Analysen von organischer und trockener Substanz in epiphysischen Schichten zeigten, daß die Menge des proliferierenden und hypertrophischen Knorpels zunahm und daß verkalkter Knorpel bei Rachitis abnahm, gemäß klassischen histologischen Beobachtungen. achtungen. Ganz unerwartet war bei Rachitis eine verhältnismäßige Zunahme des ruhenden Knorpels festzustellen.
    Notes: Abstract Electrolytes were analyzed in serum, and in mineralizing tissues at varying stages of calcification, in normal and vitamin D-deficient chickens and pigs. Moisture, ash, and organic matter were also measured. Results revealed that in addition to Ca, other serum electrolytes were altered in rickets. Mg and inorganic P were diversely affected by the vitamin deficiency. Larger changes in mineral level were seen in the tissues in the early stages of calcification than were seen at corresponding times in the serum, suggesting a direct effect of the vitamin deficiency on the calcifying tissue itself. Relative to the serum level, Ca was deposited in the tissues of rachitic animals to a greater extent than in normal animals. This was not true for Mg or inorganic P, indicating a preferential affinity for Ca in the rachitic tissue. Gravimetric analyses of organic and dry matter in epiphyseal zones revealed that the amounts of proliferating and hypertrophic cartilage were increased, and calcified cartilage decreased, in rickets, in accord with previous histological observations. Unexpectedly, the proportion of resting cartilage was also increased.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Clinical and experimental medicine 156 (1971), S. 61-66 
    ISSN: 1591-9528
    Keywords: Bone resorption ; Phosphorus ; Parathyroid hormone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of a low phosphorus diet on bone resorption is studied in thyroparathyroidectomized rats. Bone resorption is estimated from the marrow cavity area of a cross-section of the tibia. The rate of calcium mobilisation from bone is estimated by serum specific activity of45Ca/40Ca after labelling of the diet. Bone resorption is increased by feeding a low phosphorus diet, suggesting a direct effect of hypophosphatemia stimulating bone resorption, independent of any action of parathyroid hormone.
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  • 11
    ISSN: 1432-0827
    Keywords: Bone ; Epiphyses ; Calcification ; Physiologic ; Phospholipids ; Phosphorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Neuf polets, âgés de huit semaines, ont reçu 1 mCi de32P orthophosphate par voi intrapéritonéale. Ils ont été sacrifiés 2, 14, 38, 86 et 169 heures asprès injection. Les épiphyses des os longs ont été prélevées et séparés en cartilage au repos, cartilage en voie de prolifération, cartilage en voie de calcification et os spongieux primitif. Les lipides sont extraits: chaque tissu est déminéralisé et les lipides sont extraits à nouveau. On détermine ainsi le contenu en lipides totaux et en phospholipides, ainsi que leurs divers types et l'activité spécifique relative: Le contenu lipidique total de tous les tissus épiphysaires est de 1,35 à 4,52% en poids sec de matrice déminéralisée. La fraction phospholipipidique constitue environ la moitié des lipides. Dans les régions à contenu élevé en calcium, plus de phospholipides sont extraits après déminéralisation qu'avant. Des phospholipides neutres constituten 80–90% des phospholipides totaux dans les extraits réalisés avant déminéralisation, et seulement 48–65% dans les extraits après déminéralisation. La quantité des phospholipides, éthanolamine et sérine, est variable dans les diverses zone épiphysaires. La quantité et les types de phospholipides et leur rapport avec le degré de calcification concordent avec les résultats publiés pour les tissus de veaux. Les courbes d'activité spécifique démontrent une activité réduite au niveau de cartilage au repos et des échange très actifs en phospholipides dans les trois autres zones épiphysaires. Les divers types de phospholipides ont des activités métaboliques nettement différentes les uns par rapport aux autres. Les modes d'échanges particuliers de la phosphatidyle ethanolamine, de la phosphatidyle sérine et de la phosphatidyle inositol, au niveau du cartilage en voie de prolifération et de calcification, suggérent un rôle spécial de ces lipides dans le mécanisme de las croissance et de la calcification.
    Abstract: Zusammenfassung Neun achtwöchige Hühner erhielten intraperitoneal 1 mCi32P-Orthophosphat und wurden 2, 14, 38, 86 und 169 Std nach der Injektion getötet. Die Epiphysen der Röhrenknochen wurden seziert und ruhende, proliferierende und verkalkende Knorpel, sowie primäre Spongiosa voneinander getrennt. Die Lipide jeder Zone wurden extrahiert, jedes Gewebe wurde demineralisiert und die Lipide erneut extrahiert. Der Gehalt der Extrakte an Gesamtlipden und Phospholipiden sowie die Art der Phospholipide wurden bestimmt und die relative spezifische Aktivität: gemessen. Der Gehalt an Gesamtlipiden aller epiphysischen Gewebe betrug 1,35–4,52% des Trockengewichtes der demineralisierten Matrix. Phospholipide machten ungefähr die Hälfte der Gesamtlipide aus. In den Zonen mit hohem Calciumgehalt konnten mehr Phospholipide nach der Demineralisation als vorher extrahiert werden. Die neutralen Phospholipide entsprachen in vor der Demineralisation erhaltenen Extrakten 80–90% und in jenen nach der Demineralisation nur 48–65% der gesamten Phospholipide. Die Aethanolamin- und Serinphospholipidmengen variierten bedeutend in den verschiedenen Zonen der Epiphyse. Die Menge und die Art der Phospholipide und ihr Verhältnis in bezug auf Verkalkungsgrad waren in Einklang mit den Werten, die für das Kalb angegeben werden. Die Kurven der relativen spezifischen Aktivität zeigten ein träges metabolisches Muster im ruhenden Knorpel und einen sehr aktiven Phospholipidumsatz in den drei anderen Zonen der Epiphyse. Die verschieden gearteten Phospholipide zeigten untereinander merklich verschiedene metabolische Muster. Die speziellen Eigenschaften der Umsatzsmuster von Phosphatidyläthanolamin, Phosphatidylserin und Phosphatidylinositol in proliferierendem und verkalkendem Knorpel lassen vermuten, daß diese Lipide spezielle Funktionen im Wachstums- oder Verkalkungsprozeß ausüben.
    Notes: Abstract Nine eight-week old chicks were given32P orthophosphate, 1 mCi, intraperitoneally and killed 2, 14, 38, 86, and 169 hours after injection. Long bone epiphyses were dissected and separated into resting cartilage, proliferating cartilage, calcifying cartilages, and primary spongiosa. Lipids were extracted from each zone, each tissue was demineralized, and lipids were extracted again. The extracts were analyzed for total lipid and phospholipid content, types of phospholipids, and relative specific activity. Total lipid content of all epiphyseal tissues was 1.35 to 4.52% of the dry demineralized matrix weight. Phospholipid was about half the total. In the zones with higher calcium content more phospholipid was extracted after demineralization that before. Neutral phospholipids were 80 to 90% of the total phospholipids in predemineralization extracts and only 48 to 65% in extracts after demineralization. The amount of ethanolamine and serine phospholipids varied considerably in different epiphyseal zones. The amount and types of phospholipid and their relation to degree of calcification corroborated data reported for the calf. Relative specific activity curves revealed a sluggish metabolic pattern in resting cartilage and very active phospholipid turnover in the other three epiphyseal zones. The different types of phospholipids had markedly different metabolic patterns from each other. Special features of the turnover patterns of phosphatidyl ethanolamine, phosphatidyl serine, and phosphatidyl inositol in proliferating and calcifying cartilage suggest special roles of these lipids in the growth or calcification process.
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  • 12
    ISSN: 0570-0833
    Keywords: Tetradentate ligands ; P ligands ; Arsenic ligands ; Phosphorus ; Arsenic ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of ligand shape on coordination numbers and geometry of coordination compounds has been studied using two tetradentate ligands containing phosphorus and arsenic. These tend to form five-coordinate complexes with trigonal bipyramidal structure [Fe(II), Co(I), Co(II), Rh(I), Ni(II), Pd(II), Pt(II)], but can also form six-coordinate complexes with octahedral structure [Fe(II), Ru(II), Os(II), Co(III), Rh(III), Pd(IV), Pt(IV)]. The magnetic properties and the stereochemistry of the complexes are explained by ligand field theory which predicts that, for metal ions with d6-electronic configuration, a low overall field strength should favor the formation of five-coordinate paramagnetic complexes while a high overall field strength should favor the formation of six-coordinate diamagnetic complexes. - This work provides further indication that the tendency of polydentate ligands to use all the potential donor atoms is not as pronounced as is generally believed. This is shown by the isolation of chromium(III) complexes in which the tetradentate ligands are, in fact, acting as tridentate, and by the isolation of mercury(II) complexes where only two of the four donor atoms of the polydentate ligand are actually bonded to the central metal atom.
    Additional Material: 9 Ill.
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  • 13
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 523-530 
    ISSN: 0570-0833
    Keywords: Semimetals ; Metallic structure ; Nonmetallic structure ; Antimony ; Arsenic ; Bismuth ; Phosphorus ; Tellurium ; Tin ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Measurements on semimetals have been continued. Studies of the dependence on temperature of various properties have provided details regarding the transition from the nonmetallic to the more metallic structure. A second-order transition has been found for tin at 170 °C, in which the c-axis remains unchanged, while the a-axis undergoes a small, discontinuous elongation.
    Additional Material: 13 Ill.
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  • 14
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 2 (1963), S. 646-654 
    ISSN: 0570-0833
    Keywords: Polyphosphanes ; Phosphanes ; Phosphorus ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: While silicon and sulfur, which are situated to the left and to the right of phosphorus in the periodic table, from numerous chain and cyclic Si-Si and S-S-compounds with varying numbers of members, until recently the polyphosphance chemistry has been limited to the two-membered compounds diphosphane P2H4 and its derivatives. A number of results obtained in studies on polyphosphanes carried out in recent years will therefore be discussed, which, together with some more recent work by other authors, have led to an expansion of our knowledge of the prepration and properties of straight and branched-chain as well as of cyclic and polycylic -P-P-systems.
    Type of Medium: Electronic Resource
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  • 15
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 617-621 
    ISSN: 0570-0833
    Keywords: Isocyanates ; Phosphorus ; Silicon ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several aminoaryl esters of phosphoric and thiophosphoric acids were prepared by the reaction of phosphorus pentahalides with nitrophenols, followed by catalytic hydrogenation, or by treating aminophenols with phosphorus trihalides and oxidation to pentavalent phosphorus. These amino esters were then converted into isocyanato esters by the action of phosgene. Isocyanates of phosphonates have been synthetized on the same principle, as well as via the Arbusov reaction of halogen-substituted isocyanates with trialkyl phosphites. The reaction of silicon halides or alkylhalogenosilanes with aminophenols yielded aminoaryl esters of silicic acid or its derivatives, which could also be treated with phosgene to convert them into isocyanato esters.
    Type of Medium: Electronic Resource
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  • 16
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 1 (1962), S. 652-656 
    ISSN: 0570-0833
    Keywords: β-Chloroethanephosphonic dichloride ; Phosphorus ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ethylene, phosphorus trichloride, and oxygen react together to give β-chloroethylphosphonic dichloride in good yields. Being a bifunctional acid chloride, this compound undergoes polycondensation reactions with other, at least bifunctional, compounds affording polyesters, polyamides, epoxy resins, etc. β-Chloroethylphosphonic dichloride also may be converted into vinylphosphonic dichloride, thus serving as a starting material for the preparation of vinylphosphonic acid and its derivatives. These undergo both homopolymerization and copolymerization with compounds containing olefinic double bonds. The products are used in the field of synthetic resins, for dressing textiles, and as protective surface coatings.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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