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Summary Intraperitoneal injection of allogeneic liver cells from 43-day-old male fetuses into normal 60-day female goat fetuses resulted in persistent hemopoietic chimerism in surviving recipients without clinical evidence of graft-versus-host disease. Transplantation of normal fetal liver cells into preimmunocompetent goat fetuses affected with -D-mannosidosis may provide an alternative strategy for evaluating hemopoietic stem cell transplantation in the treatment of human lysosomal storage diseases.  相似文献   

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Zusammenfassung Man kann «post-irradiation»-bedingtes Ablehnungsverhalten indirekt herbeifuhren, indem man Hirngewebe von abgerichteten Mäusen in den Peritonealraum der unabgerichteten Mause injiziert. Die «Empfänger» verhalten sich, als seien sie selbst dem Saccharinbevorzugungs-Test und anschliessend ionisierender Bestrahlung ausgesetzt worden. Wir haben zur Zeit noch keine stichhaltige Erklärung für diese interessante Beobachtung.

This work was done at the Radiation Research Laboratory, College of Medicine, University of Illinois, Chicago (Illinois, USA).  相似文献   

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Zusammenfassung Die i.p. Injektion von Endotoxin führt bei der Ratte zum vermehrten Auftreten von Mitosen in Mesothelzellen. Vereinzelt kommt es zur Verbreiterung der Interzellularräume, äusserst selten treten Siegelringzellen auf. Es wird vermutet, dass eine geringe endotoxinbedingte Zellschädigung den Stimulus zur Mesothelzellproliferation darstellt.  相似文献   

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Summary [14C]Orotic acid was rapidly distributed in blood after, both i.p. and s.c. injection but was not completely absorbed from the peritoneal cavity until 20 min after injection. S.c. injection should be an acceptable alternative to i.p. injection although the incorporation into the liver acid soluble- and RNA-fractions was somewhat delayed after the s.c. injection.This work was supported by grants from the Carl Trygger Foundation and the Foundation of Director Albert Påhlsson.  相似文献   

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Résumé Des organes de plantes ou d'animaux mis dans une suspension bactérienne synthétisent du RNA bactérien. Ce phénomène que nous avons appelé transcession est dû au transfert de DNA spontanément cédé par les bactéries vivantes aux cellules des organismes supérieurs. Dans le présent travail, il est démontré que le même phénomène peut avoir lieu naturellement lorsqu'une grenouille est sujette à une infection bactérienne.

We thank MissA. Cattaneo, MissJ. Henry for excellent technical assistance. This work was supported by a grant from the Fonds National Suisse de la Recherche Scientifique.  相似文献   

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Very little is known about the modulation of vanadium accumulation in cells, although this ultratrace element has long been seen as an essential nutrient in lower life forms, but not necessarily in humans where factors modulating cellular uptake of vanadium seem unclear. Using nuclear microscopy, which is capable of the direct evaluation of free and bound (total) elemental concentrations of single cells we show here that an NH4Cl acidification prepulse causes distinctive accumulation of vanadium (free and bound) in human Chang liver cells, concentrating particularly in the nucleus. Vanadium loaded with acidification but leaked away with realkalinization, suggests proton-dependent loading. Vanadyl(4), the oxidative state of intracellular vanadium ions, is known to be a potent source of hydroxyl free radicals (OH.). The high oxidative state of nuclei after induction of vanadyl(4) loading was shown by the redox indicator methylene blue, suggesting direct oxidative damage to nuclear DNA. Flow cytometric evaluation of cell cycle phase-specific DNA composition showed degradation of both 2N and 4N DNA phases in G1, S and G2/M cell cycle profiles to a solitary 1N DNA peak, in a dose-dependent manner, effective from micromolar vanadyl(4) levels. This trend was reproduced with microccocal nuclease digestion in a time response, supporting the notion of DNA fragmentation effects. Several other approaches confirmed fragmentation occurring in virtually all cells after 4 mM V(4) loading. Ultrastructural profiles showed various stages of autophagic autodigestion and well defined plasma membrane outlines, consistent with programmed cell death but not with necrotic cell death. Direct intranuclear oxidative damage seemed associated with the induction of mass suicide in these human Chang liver cells following vanadium loading and nuclear sequestration.  相似文献   

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Résumé Une immunité active au sarcome, produit par le cholanthrène de méthyle, a été obtenue en utilisant des cellules tumorales multinucléées, associées au virus de Sendai; les réactions ont été spécifiques à la tumeur. A la suite de ces injections, plus de 70% des souris furent résistantes aux trois inoculations, avec 105 cellules vivantes tumorales.  相似文献   

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Summary Spleen and marrow tissues were cross-transplanted between CBA and CBA/HT6 mice. The majority of karyotypes in the regenerated implants were of recipient origin indicating that these implants are chimeric structures with the stroma of donor origin providing a framework for the proliferation of the recipient's hemopoietic stem cell.Supported by NIH Grant AM25510-01 and DOE contract 79EV00899. R. Khademi is currently with University of Isfahan, Iran.  相似文献   

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V.S.V. induced polycaryocytes in rat embryonic fibroblasts, transformed by the Prague strain of Sarcoma Rous (XC cells). This fusion is strictly dependent on the expression of the viral genome and is probably due to the incorporation of viral antigens in the cell membrane. The integrity of cellular RNA synthesis is however not required. The fusion is probably due to a membrane structure characteristic of these transformed cells.  相似文献   

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The responsiveness of fetal mouse Leydig cells to catecholamines (epinephrine, norepinephrine), a beta-agonist agent (L-isoproterenol) and hCG was investigated in vitro. Fetal Leydig cells when freshly isolated were unable to respond to L-isoproterenol (10(-5) M). However, L-isoproterenol, epinephrine and norepinephrine significantly stimulated androgen production by fetal Leydig cells after 24 h of primary culture. Androgen production was increased in both conditions and to a greater extent by hCG. Propranolol blocked the stimulatory effect of L-isoproterenol and epinephrine. It is concluded that catecholamines can regulate fetal testosterone biosynthesis.  相似文献   

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Day 25 after insemination is a date of peculiar importance in the maturation of several organs in the Rabbit fetus. From day 25 onward the fetal liver stores increasing amounts of glycogen and the lung stores increasing amounts of lecithins, concomitant with sudden rise in the activity of lung phosphatidic-acid phosphohydrolase. Earlier studies on decapitated fetuses established that glycogen storage in the liver is dependent on a dual hormonal control, comprising a pituitary hormone like growth hormone or prolactin (some placental hormones share the same activity) and corticosteroids (Jost, 1961). Since the variations in endogenous corticosteroids do not seem to herald these liver or lung changes (Mulay et al., 1973), a study was made of growth hormone. Plasma immunoreactive growth hormone--determined with a heterologous Rat system (Kervran et al., 1976)--increases eightfold between days 23 and 25. During the same time plasma prolactin does not change according to McNeily and Friesen, 1978, and to unpublished data obtained with Dr McNeilly. In preliminary assays, Rat growth hormone was seen to increase phosphorylase "a" activity in the lung of 18.5 day-old Rat fetuses, thus anticipating normal development. We suggest that growth hormone plays a role in initiating liver and lung maturation.  相似文献   

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