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931.
Summary Desheathed rabbit vagus nerve has been found to form cyclic AMP when incubated with adenosine. This accumulation of cyclic AMP is inhibited by theophylline but not by antiadrenergic agents, anticholinergic agents or local anaesthetics. Depolarizing media are not able to promote cyclic AMP accumulation in this preparation.Acknowledgment. We gratefully acknowledge Mr.G. Jones for valuable discussion, MrsM. Moosmayer and Mr.S. Ferrara for expert technical assistance and Swiss National Science Foundation for grant support (Nr. 3.478.0.75). 相似文献
932.
933.
Summary Stimulation of aminopyrine demethylation induced in rats by oral or i.p. administration of phenobarbital was partially inhibited in animals receiving daily treatments of 2×200 mg/kg gum Arabic p.o. 相似文献
934.
G Barchewitz F Binon A Cier H Tuchmann-Duplessis 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1980,291(4):409-411
When orally administered, 5-(3-diméthylamino propyliden)-benzofuro [2,3-c] benzoxepin-1, which antagonizes several biogenic amines, is slightly sedative and has also endocrinological properties in the Rat, induces the appearance of localized lesions of uterine stroma in 2 to 16% of the animals. The cytological picture could suggest a tumorogenesis. In fact, these lesions represent a non-tumoral reactional hyperplasia with nuclear abnormalities due to a hormonal stimulation. 相似文献
935.
Effect of conditioned media on nerve cell differentiation 总被引:2,自引:0,他引:2
M. Sensenbrenner G. G. Jaros G. Moonen B. J. Meyer 《Cellular and molecular life sciences : CMLS》1980,36(6):660-662
Summary Glial conditioned medium strongly stimulates the morphological maturation of cultured neuronal cells, while fibroblast and meningeal conditioned media have weaker effects.Acknowledgment. We acknowledge the expert technical assistance of Mrs M.F. Knoetgen. 相似文献
936.
G. H. Rossmanith J. Unsworth R. D. Bell 《Cellular and molecular life sciences : CMLS》1980,36(1):51-53
Summary Small-amplitude sinusoidal displacements, in the frequency rang 4–100 Hz, were applied to intact whole frog sartorius muscle whilst in a state of tetanus. At low frequencies the muscle, was observed to do oscillatory work, while at higher frequencies it tended towards elastic behaviour. Frequency-response plots obtained were compared with those from other muscle preparations. Results were interpreted in terms of mechano-chemical transduction properties of muscle.The authors wish to thank the Australian Research Grants Commission for provision of the laser, and L. I. Patterson for construction of the mechanical apparatus. 相似文献
937.
Retroviral antigens on gs- chf- leukocytes 总被引:1,自引:0,他引:1
It has recently been suggested that the endogenous retroviruses present in many different species might be involved during stimulation of the immune system of their hosts. We have now studied the expression of two avian retroviral antigens p27 and gp85 in chicken lymphoid cells by indirect immunofluorescence (IIF) and by complement-dependent microcytotoxicity (CDM). We have now found that these viral antigens are expressed in peripheral blood leukocytes of adults and embryos and in splenic and bursal lymphocytes of Spafas gs- chf- chickens but they are not expressed in fibroblasts cultured from the feather follicles of the same individual adult birds nor in fibroblasts cultured from embryos of the same flock. The differential expression of viral antigens in leukocytes may be related to a specific property or function of these cells. 相似文献
938.
R Catania W Streiff P Lubet 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(3):203-205
Study of solubility of neurosecretory products in Crepidula fornicata shows that the presence of ethanol in the fixative is incompatible with good fixation. This character permits the choice of a more effective extraction technique. An experimental study in organ culture shows that the action of differentiation of brain appears in the extract obtained by this method. 相似文献
939.
Site specific integrative recombination of bacteriophage lambda involves unequal partners. The minimal phage att site is composed of approximately 240-base pairs and four distinct binding sites for Int protein, at least three of which are crucial for function. This 'donor site' recombines efficiently with a smaller 'recipient site' that lacks the extensive interactions with Int protein. 相似文献
940.