Ultrastruktur der Ovozyten vonOrnithodorus moubata,Murray (Ixodoidea:Argasidae) nach Triple-Fixation

Summary The triple-fixation (simultaneous fixation in a mixture of glutaraldehyde and osmium tetroxide and post-treatment in aqueous uranylacetate) is especially suitable for the demonstration of membranes and to distinguish different types of vesicles in the oocytes of the soft tickOrnithodorus moubata.

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Die Arbeit wurde vom Schweiz. Nationalfonds unterstützt.

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Frau S.Latscha-Stoller danke ich für ihre unentbehrliche technische Mitarbeit.     

Entwicklung der Symbiontenorgane einer Kleinzikade (Euscelis plebejus Fall.) nach Ausschaltung der Symbionten

Summary Embryos of the leafhopperEuscelis plebejus Fall. deprived of their intracellular symbionts are known to develop larval mycetomes of apparently normal topography late in embryogenesis. New experiments indicate that even the provisional mycetome preceding the larval structure is formed during early development of asymbiotic eggs.     

Die Treffermethode in der Messung der Parathyreozyten-Aktivität nach der Epiphysektomie

Résumé Par l'application de la méthode d'intégration aux points sur les clichés électronomicroscopiques, on a constaté l'hypertrophie des organelles cellulaires (mitochondries, le réticulum endoplasmique et l'appareil de Golgi) dans les cellules parathyroïdiennes de rats sacrifiés trois semaines après l'épiphysectomie.     

Untersuchungen der Pollenkörner vonAlnus rugosa (Du Roi) Spreng. im Interferenzmikroskop nach Nomarski

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.     

Verlust der Proliferationsfähigkeit der Hepatozyten nach subtotaler Hepatektomie

Summary After resection of 90% of liver tissue, no significant increase of thymidine-³H labelling or mitotic index of hepatocytes can be observed in rats. The minimum residual liver mass critical for inducibility of proliferation and, in consequence, essential for survival of rats is more than 10% and less than 18% of the total liver parenchyma.     

Proliferationen der Fischepidermis nach der Einwirkung von inhibitoren des glykolytischen Energiestoffwechsels

Summary When fluoride-ions or monoiodoacetate is added to the ambient medium, there occur in fish larvae after 12 h, and in eels after 24 h, in some places, solid epidermal proliferations. The effect of glycolysis inhibitors on epidermal mitotic activity might be due to an impairment of energy metabolism as it is nullified by a simultaneous application of inorganic diphosphate or by doubled O₂ partial pressure of 320 mm Hg.     

Ultrastruktur der Symbionten in Ovozyten vonOrnithodorus moubata,Murray (Ixodoidea:Argasidae) nach simultaner Glutaraldehyd-Osmiumfixierung und Nachbehandlung mit Uranylacetat (Triple-Fixation)

Summary The nucleoplasm of rickettsia-like microorganisms living in the oocytes of the soft tickOrnithodorus moubata is preserved by TF (triple-fixation) in a fine fibrillary form, resembling the results obtained by the standard-method for DNA-containing plasms.

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Die Arbeit wurde vom Schweiz. Nationalfonds unterstützt.

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Frau S.Latscha-Stoller möchte ich für ihre unentbehrliche technische Mitarbeit meinen besten Dank aussprechen.     

Teratogene Wirkung der N-Phthalyl-dl-glutaminsäure nach intraperitonealer Applikation bei der Maus

Summary Phthaloyl-dl-glutamic acid, a metabolite of thalidomide, was found to exert a teratogenic effect after i.p. administration to pregnant mice. The injected solution contained Tween 20 as solubilizer.     

Die Mitosehäufigkeit in der normalen Epidermis der Maus nach einmaliger DMSO-Einwirkung

Summary 12 h after local application of DMSO on the epidermis of the mouse, increased mitotic activity has been observed, the maximum occurring 24 h after the onset of the experiment. Subsequently a distinct reduction of the frequency of mitosis can be seen with a minimum occurring about 53 h after the beginning of experiment. The initial mean value is reached 12 h after.     

Veränderungen der Ploidiestufe von Leberparenchymzellen nach Hypophysektomie

Résumé Après l'hypophysectomie, chez les rats Wistar mâles, le nombre des cellules mononucléaires tetraploÏdes du foie s'abaisse de 70% à 28%, tandis que le nombre des octoploÏdes diminue de 19,8% à 0%.     

Ultrastrukturelle untersuchungen der juxtaepiphysären kapillaren nach perfusionsfixation

Summary Afger perfusion-fixation, the juxtaepiphyseal capillaries reveal endothelial cells with pores and without basement-membrane. Extravasates of erythrocytes are artefacts and are due to overexpanding of the endothelial cells in a loosened cartilage matrix.     

Beitrag zur Frage nach der Beteiligung lebender Stammzellen am Saftsteigen

Ohne Zusammenfassung     

Mesothelzellveränderungen nach der intraperitonealen Injektion von denaturiertem Phytohaemagglutinin

Summary After the i.p. injection of heat denatured PHA, mesothelial cell changes are similar to those found after the application of natural PHA. While vacuolization of mesothelial cells and signet ring cell formation is strongly marked after the injection of natural PHA, this reaction is minor if denatured PHA is used. Furthermore, the peritoneal fluid does not contain hyaluronic acid in detectable amounts.

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Die Untersuchungen wurden mit finanzieller Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt.     

Die Aktivität der alkalischen Phosphatase im Rattenharn nach Mastzelldegranulierung

Summary Alkaline phosphatase activity was determined in rat urine under normal conditions (80 animals) and following mast cell depletion (30 animals). A statistically significant increase in urinary APA was found after administration of the mast-cell depleting compound 48/80. This fourfold increase over normal activity is due to renal changes caused by shock.     

Morphometrische Untersuchungen an der Rattenleber — Parenchymzelle nach Anwendung verschiedener Fixationspuffer

Summary The effect of 2 fixatives, (1) s-Collidin buffered OsO₄, (2) phosphate buffered OsO₄, on the liver cell was studied by morphometric analysis. After fixation with solution 2, large areas of smooth endoplasmic reticulum were covered by electron-opaque deposits of glycogen. No such masking was noticed by using solution 1. Other cell organelles showed no significant differences in their relative volumes. By using fixative solution 2, decrease in glycogen can simulate relative volume increase of the smooth endoplasmic reticulum.

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Wesentliche Teile der vorliegenden Arbeit wurden von Frl. F.Stockmann der Medizinischen Fakultät der Universität Basel als Inaugural-Dissertation vorgelegt.     

Heterologe Transplantation von Tumoren nach Vorbehandlung der Wirtstiere mit radioaktiven Isotopen

Summary The investigation deals with the successful heterologous transplantation of the Mouse Crocker-Sarcoma on young rats, that were pretreated with the radioactive isotopes P³² and Au¹⁹⁸. The growth tendency of the tumours varies according to the character of the radioactive isotope, the mode of administration and the interval between the injection of the radioactive substance and the heterotransplantation.     

Veränderungen der aggressiven Handlungsbereitschaft männlicher Schwertträger,Xiphophorus helleri,nach sozialer Isolation (Fische,Poeciliidae)

Summary IfXiphophorus helleri males are kept in social isolation for 14–56 days, the fights for rank order position showed an increasing duration and intensity. These results support the idea of a spontaneous accumulation of attack readiness and are in contrast to the results in cichlid fishes. It is supposed that the different influence of social isolation to aggressive behaviour corresponds to different types of social organisation anp ecological adaptations.

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Mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Das Elektrovenogramm (Evg) der isolierten Flughautvene (Chiroptera)

Summary The electrovenogram of the isolated vein of the wing membrane (Chiroptera) exhibits two main irregularities in its diphasic action current—a fast initial wave before the beginning of the systole and a very protracted after-wave. Following this the rise and fall of potential run parallel with the contraction and dilatation of the vessels.     

Störungen der Zahnentwicklung bei Rattenembryonen nach Gaben von 6-Aminonicotinamid

Summary Application of 6-aminonicotinamide to rats during pregnancy produced malformations, resorption and retardation. A dose of 8 mg/kg 6-AN between day 12 and 17 of pregnancy can affect the development of teeth germ. Electron microscopic studies reveal disturbances of the epithelial part of the teeth germ only, with an extreme balooning of the perinuclear cistern.