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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Histochemistry and cell biology 25 (1971), S. 152-162 
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei Hunden, Hausschweinen, Wistarratten und Albinomäusen wurde das Vorkommen von Arginin im Neurosekret des supraoptico-hypophysären Systems mit der von Rosselet angegebenen Fluoreszenzreaktion untersucht. Das Verfahren basiert auf der Bildung einer fluoreszierenden Verbindung durch Anlagerung eines im alkalischen Milieu entstehenden Umwandlungsproduktes des Ninhydrins an die Guanidogruppe des Arginins. Bei allen aufgeführten Spezies zeigte das neurosekretorische Material im Hypophysenhinterlappen eine positive Argininreaktion. Auch in den Zellen der Nuclei supraopticus und paraventricularis konnte bei allen Spezies mit Ausnahme der Maus Arginin nachgewiesen werden. Dagegen ließen sich mit der Methode bei keiner Spezies die Fasern des Tractus supraoptico-hypophyseus hervorheben. Die Argininspezifität der Reaktion wurde durch mikrospektrographische Untersuchungen bestätigt. Aus dem Nachweis von Arginin im Neurosekret des Schweines folgt, daß es sich bei dem neurosekretorischen Material nicht um die Hinterlappenhormone selbst, sondern nur um deren Trägerproteine handeln kann.
    Notes: Summary In the neurosecretory material of the supraoptico-hypophysial system of dogs, pigs, rats, and mice arginine was shown to occur by means of the method of Rosselet. This method is based on the fact that arginine reacts with a ninhydrin derivate to give a fluorescent compound which can be localized in histological sections. In all species investigated, the neurosecretory material in the pituitary posterior lobe has been found to give a positive reaction. In addition, arginine was found in the nerve cells of the supraoptic and paraventricular nuclei of all species except mice. In contrast, no arginine could be demonstrated in the tractus supraoptico-hypophyseus of any of the species investigated. The arginine specificity of the reaction was confirmed by microspectrographic investigations. From the finding that the neurosecretory material of pigs contains arginine it can be concluded, that this material is not identical with the posterior lobe hormones, because in the pig these hormones are free of arginine. It is thus likely that the neurosecretory material represents the carrier protein of the hormones.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Histochemistry and cell biology 21 (1970), S. 353-365 
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im Tanycytenependym des III. Ventrikels kommen bei der Wistarratte unspezifische, E 600-empfindliche und gegenüber p-Chlormercuribenzoat resistente Esterasen vor. Um diese Enzyme histochemisch weiter zu charakterisieren, wurde ihre Fähigkeit geprüft, verschiedene Naphthol-Carbonsäureester bei Anwesenheit von Lösungsvermittlern zu spalten. Es zeigte sich hierbei ein unterschiedliches Verhalten der Esterasen in Ganglienzellen und Tanycyten. In letzteren weist von verschiedenen homologen Carbonsäureestern des α-Naphthols der Buttersäureester die höchste Spaltungsrate auf; Acetatester der Naphthol-AS-Reihe ergeben unterschiedliche, aber stets schwächere Reaktionen als α-Naphthylacetat. Wie in früheren Untersuchungen wurden Unterschiede im Verhalten der Esterasen-Aktivität in Perikaryen und Fortsätzen der Tanycyten beobachtet. — Auf Grund der Befunde wird die Möglichkeit einer Einschaltung der Tanycytenesterasen in die Erregungsübertragung diskutiert.
    Notes: Summary In the Wistar rat, the tanycytes of the IIIrd ventricle contain unspecific esterases which are E 600 sensitive and are not inhibited by p-chlormercuribenzoate. To further investigate the character of these enzymes, their ability to split various naphtholcarbonic acid esters in the presence of organic solvents was tested. It was hereby established that the esterases of the tanycytes behave differently to those of the diencephalic nerve cells. In the tanycytes among various homologous carbonic acid esters of α-naphthol applied, α-naphthyl butyrate shows the highest splitting ratio; with acetate esters of AS-naphtholes differing but always weaker reactions are obtained than with α-naphthyl-acetate. As in a former study, behavioral divergencies of esterase activity in the tanycyte perikaria and processes were observed. — On the basis of these findings the possibility is discussed that the esterases of the tanycytes might play a role in synaptic transmission.
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  • 13
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung An 40 männlichen Wistarratten wurden histochemisch differenzierbare Eigenschaften der unspezifischen Esterasen in den Tanycyten des III. Ventrikels, im Subfornicalorgan (SFO) und im Subcommissuralorgan (SCO) miteinander verglichen. Aus den Befunden geht hervor, daß die Esterasen des SFO in ihrem Verhalten denen der Tanycyten nahezu vollständig gleichen, während die Esterasen des SCO einen gänzlich anderen Typ verkörpern. Dieses Ergebnis könnte auf eine funktionelle Verwandtschaft von Tanycyten und Subfornicalorgan hinweisen.
    Notes: Summary In 40 male Wistar rats, a comparative study was made between the histochemically distinguishable properties of the unspecific esterases in the tanycytes of the third ventricle, in the subfornical organ (SFO) and in the subcommissural organ (SCO). The results show that the esterases of the SFO behave in an almost identical manner to those of the tanycytes, whereas the esterases of the SCO are of a completely different type. This finding could be an indication of a functional relationship between the tanycytes and the subfornical organ.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 49-62 
    ISSN: 1432-1912
    Keywords: Corticotropin-Releasing Factor ; Corticoids ; Median Eminence ; Rat ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In 465 female Wistar rats the influence of an i.m. injection of various natural or synthetic corticoids on the augmentation of “Gomori-positive” granules in the outer layer of the median eminence following bilateral adrenalectomy has been investigated. While the augmentation of the granules is not impaired by progesterone it is inhibited or completely blocked, depending on the dose and the manner of application, by 11-desoxycorticosterone, corticosterone, cortisol, 9α-fluorocortisol, prednisolone, triamcinolone, dexamethasone and fluoroformylone. The doses necessary to suppress the augmentation of the granules correspond to those shown by other authors to be required for blocking ACTH-secretion. The inhibitory effect of the investigated corticoids on the augmentation of the granules is related to their antiphlogistic potency. The findings suggest that the amount of the “Gomori-positive” granules in the outer layer of the median eminence of the rat might be used as a parameter of the activity of the corticotropin-releasing factor.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Journal of neurology 192 (1967), S. 246-264 
    ISSN: 1432-1459
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird an Hand von klinischen und tierexperimentell erhobenen Befunden zusammenfassend über das Vorkommen von ein-, mehr- und vielkernigen Riesenzellen im Liquor cerebrospinalis berichtet. Die verschiedensten Formen der Riesenzellen werden dargestellt, in mehrere Gruppen unterteilt und im einzelnen besprochen. Dabei wurde festgestellt, daß Riesenzellen (RZ) im Liquor pathologische, jedoch unspezifische Zellen sind, die vermutlich aus dem reticulohistiocytären Gewebe im Bereich der Leptomeninx gebildet werden und bei den verschiedensten, insbesondere jedoch chronischen, unspezifischen und spezifischen Erkrankungen und Begleitreaktionen des Gehirns und Rückenmarks im Liquor auftreten können. Die extrem großen, vielkernigen Riesenzellen vom Langhans-und Fremdkörper-Typ wurden besonders bei der Meningitis tuberculosa beobachtet, tierexperimentell erzeugt und vereinzelt auch bei anderweitigen Erkrankungen des Zentralnervensystems (ZNS) nachgewiesen, die durch körpereigene oder körperfremde Stoffe mitbedingt waren, welche in den Liquorraum gelangten und zu einer erheblichen meningealen Reaktion führten. Weitere Möglichkeiten der Entstehung von RZ werden dabei in Erwägung gezogen. RZ im Liquor cerebrospinalis sind funktionell aktive und biologisch vollwertige Zellen, die etwa mit den mononucleären Makrophagen gleichzusetzen sind. Sie können sowohl corpusculäre als auch kolloidale, körpereigene und körperfremde Stoffe oder Zerfallsprodukte phagocytieren, speichern und infolge ihrer fermentativen Potenzen strukturell umgestalten. Damit stellen die RZ im Liquor cerebrospinalis einen wichtigen Faktor im Abwehrmechanismus des ZNS dar.
    Notes: Summary Clinical data and those from animal experiments on the occurrence in cerebrospinal fluid of giant cells containing one, several, or multiple nuclei are summarized. The various forms of giant cells are described, divided into several groups, and individually discussed. It was found that giant cells of cerebrospinal fluid are pathological, though unspecific cells probably derived from reticulohistiocytic tissue of the leptomeninx, and appearing in various diseases, mainly, however, in chronic, specific as well as unspecific disorders involving primarily or secondarily the brain and spinal cord. The extremely big multinucleate giant cells of the Langhans or foreign body type were predominantly observed in tuberculous meningitis. They could also be produced experimentally in animals and were found occasionally in other pathological states of the central nervous system in which endogenous or exogenous agents were participating by reaching the cerebrospinal fluid spaces and causing marked meningeal reactions. Additional mechanisms inducing the formation of giant cells are taken into consideration. Giant cells of cerebrospinal fluid are functionally active and biologically viable cells roughly equivalent to mononuclear macrophages. They are able to incorporate, store and, by virtue of their enzymes, structurally alter corpuscular and colloidal material or degradation products of endogenous or exogenous origin. The giant cells thus play an important part in the defense mechanisms of the central nervous system.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 100 (1974), S. 243-252 
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Carbon Monoxide Trace-Measurement ; 14C-Glucose ; CO Production ; Atmospheric Cycle of Trace Gases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Mit einer empfindlichen Analysenmethode, die auf die Reaktion CO+HgO→CO2+Hg basiert und den CO-Gehalt auf Grund der Absorption des freigesetzten Hg bei 2537 Å ermittelt, wurden im Gasraum über wachsenden Kulturen von Saccharomyces cerevisiae, S. oviformis, Escherichia coli, Aerobacter aerogenes, Pseudomonas spec. und Lactobacillus brevis 0.4–2.6 ppm CO nachgewiesen. Bei Lactobacillus arabinosus, Bacillus cereus var. mycoides und Aspergillus niger war eine CO-Bildung nicht meßbar. 2. Bei S. cerevisiae war die CO-Bildung bei Konzentrationen von 10–50 g Glucose pro Liter Medium am größten. Außerdem wurde die CO-Bildung proportional zum anfänglichen Sauerstoffgehalt im Gasraum über den Kulturen gefördert. 3. Mit 14C-markierter Glucose wurde nachgewiesen, daß CO aus Glucose entsteht. 4. Die CO-Bildung der untersuchten Mikroorganismen ist so gering, daß sie keine Bedeutung für den Kreislauf dieses Spurengases in der Atmosphäre hat.
    Notes: Summary 1. Growing cultures of Saccharomyces cerevisiae, S. oviformis, Escherichia coli, Aerobacter aerogenes, Pseudomonas spec. and Lactobacillus brevis produce trace amounts of CO (0.4–2.6 ppm) that can be detected in the gas space above the cultures using a sensitive analytical method based on the reaction CO+HgO→CO2+Hg. The liberated Hg is quantitatively measured by atomic absorption at 2537 Å. No CO could be detected above cultures of Lactobacillus arabinosus, Bacillus cereus var. mycoides and Aspergillus niger. 2. The maximum CO production by Saccharomyces was obtained with concentrations of 10–50 g glucose per liter medium. The amount of CO formed increased with the oxygen concentration in the gas space above the cultures. 3. Using 14C-glucose it was shown that S. cerevisiae forms CO from glucose. 4. The formation of CO by the microorganisms investigated is very small. The ratio of CO/CO2 produced is much smaller than in environmental air. Therefore it can be concluded that the production of CO by these microorganisms has probably no significance for the atmospheric cycle of this trace gas.
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  • 17
    ISSN: 1573-3297
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Description / Table of Contents: Résumé La variance des scores du test d'intelligence verbale de Wechsler à l'intérieur de paires de jumeaux dizygotes a été comparée pour un groupe de jumeaux concordants et pour un groupe de jumeaux discordants pour chacun des quatre systèmes de groupes sanguins (ABO, MNSs, Rh, Duffy). On a trouvé une variance significativement supérieure chez les jumeaux discordants pour les systèmes Rh et Duffy. On envisage plusieurs explications possibles, mais il semble que la cause la plus probable soit le “linkage” entre la localisation du gène du groupe sanguin et d'un gène important pour l'intelligence verbale. ZUSAMMENFASSUNG-Die Intrapaarvarianz verbaler Intelligenztestscores (Wechsler) bei dizygoten Zwillingen mit übereinstimmender bzw. verschiedener Blutgruppe (ABO, MNSs, Rh, Duffy) wurde verglichen. Für zwei der vier untersuchten Blutgruppen (Rh und Duffy) wurde signifikant grössere Yarianz zwischen Zwillingen gefunden, die unterschiedlichen Blutgruppen angehörten. Verschiedene mögliche Erklärungen dieses Ergebnisses werden erwogen; “linkage” des Genortes für die betreffende Blutgruppe mit dem Locus eines der wichtigeren Gene für verbale Intelligenz wird als die wahrscheinlichste vorgeschlagen.
    Notes: Abstract Within pair variances of Wechsler verbal intelligence test scores have been compared for fraternal twins that are concordant and those that are discordant for each of four bloodgroup system (ABO, MNSs, Rh, Duffy). Significantly increased variances for twins discordant for the Rh system and for Duffy were found. Several possible explanations are considered but it is proposed that linkage between the bloodgroup locus and the locus of a major gene for verbal intelligence is the most likely cause.
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  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 122 (1971), S. 456-459 
    ISSN: 1432-0878
    Keywords: Neurosecretory material ; Carrier protein ; Arginine ; Phenanthrenequinone ; Pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Neurosekret im Hypophysenhinterlappen des Schweines enthält Arginin. Dieser in einer voraufgegangenen Untersuchung mit Hilfe der Ninhydrin-Reaktion erhobene Befund wird durch die vorliegende Mitteilung bestätigt, bei der zum Argininnachweis die Phenanthrenchinon-Reaktion benutzt wurde. Aus den Befunden ist zu folgern, daß das Neurosekret als Äquivalent der Trägerproteine anzusehen ist, da die Hormone selbst beim Schwein argininfrei sind.
    Notes: Summary By using the phenanthrenequinone-reaction it is shown that the neurosecretory material in the posterior lobe of the hypophysis in pigs contains arginine. This finding confirms results previously obtained by using the ninhydrine reaction. Since in pigs the hormones vasopressin and oxytocin are free of arginine, the findings indicate that the neurosecretory material represents the carrier proteins.
    Type of Medium: Electronic Resource
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  • 19
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 152 (1974), S. 411-421 
    ISSN: 1432-0878
    Keywords: Median eminence (rat) ; External zone ; Adrenalectomy ; CRF-neurophysin ; Immunoperoxidase histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In picric acid-formalin fixed, paraplast embedded median eminence sections from normal and bilaterally adrenalectomized rats, the amount of “Gomori-positive” neurosecretory material and the amount of protein, cross reacting against a porcine neurophysin-II antiserum were determined. In normal rats, “Gomori-positive” substances and neurophysin were confined to the internal zone of the median eminence. After adrenalectomy, however, “Gomori-positive” granules and a neurophysin-like protein also became apparent in the external zone. Their amount increases, if the animals are treated with DOCA from the 15th to the 21st day after the operation. The distribution of the neurophysin-like protein in the external zone is similar to that of the “Gomori-positive” granules. Since the granules are regarded as a morphological correlate of the corticotropin-releasing factor (CRF) it is assumed, that the protein, appearing in the external zone after adrenalectomy and cross-reacting against the neurophysin antiserum is a CRF-associated neurophysin. For this substance the name “CRF-neurophysin” is proposed.
    Type of Medium: Electronic Resource
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Psychometrika 35 (1970), S. 179-197 
    ISSN: 1860-0980
    Source: Springer Online Journal Archives 1860-2000
    Topics: Psychology
    Notes: Abstract A method of estimating the parameters of the normal ogive model for dichotomously scored item-responses by maximum likelihood is demonstrated. Although the procedure requires numerical integration in order to evaluate the likelihood equations, a computer implemented Newton-Raphson solution is shown to be straightforward in other respects. Empirical tests of the procedure show that the resulting estimates are very similar to those based on a conventional analysis of item “difficulties” and first factor loadings obtained from the matrix of tetrachoric correlation coefficients. Problems of testing the fit of the model, and of obtaining invariant parameters are discussed.
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