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681.
682.
Summary The changes in short-circuit current occurring when one or both solutions bathing the intestine of rat or guinea-pig mounted in flux chambers were recorded. The results with the guinea-pig can be explained in terms of diffusion potentials arising from the ionic replacements, and an electrogenic sodium pump, sensitive to ouabain, in the contraluminal membrane of the cell. In the rat, the situation is more complicated, and the enterocyte probably possesses an electrogenic sodium pump in the brush-border membrane. 相似文献
683.
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
684.
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
685.
Summary 4000 rads of mixed gamma neutron radiation administered to rhesus monkeys released a significant amount of histamine into their circulation. When the monkeys were treated with a mast-cell histamine depleter (compound 48/80) for 4 days and then irradiated, no increase in circulating histamine was seen. When 48/80 was given 20 min after irradiation, only a slight increase in histamine was seen, indicating that 4000 rads had released most of the mast-cell histamine. 相似文献
686.
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
687.
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
688.
Summary Genic activity in tetraploid members of the amphibian speciesOdontophrymus americanus is reduced to that of diploid ones. Loss of ribosomal genes, a mechanism suggested by others as a means of decreasing genetic activity, could be ruled out. The diploids and the tetraploids have almost identical proportions of their genomes complementary to (28s+18s) ribosomal RNA. 相似文献
689.
690.