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21.
The application of different methods of tissue culture, in particular, investigations on trophoblast cells outside the mother's body, opens new possibilities for understanding pathogenesis of premature interruption of pregnancy caused by the hormonal and metabolic disorders. To study the effects of various hormones (Choriogonien, estrone and estradiol) on the growth and development of trophoblast cells the method of tissue culture was applied. 683 histological preparations, obtained after incubating trophoblast tissues with and without hormones were examined. It was established that choriogonine in doses of 5-100 IU/L stimulated growth in trophoblast cells but 200-400 IU/L of hormone did not increase this stimulating effect. Estrone and estradiol added to incubated tissues in doses of 60-120 IU/L brought about no changes or else had a weak effect on development of cultivated tissues. When choriogonine (or estrone) was added to the trophoblast tissues together with blood serum taken from women in danger of premature interruption of pregnancy the negative effect of the serum on the development of the trophoblast cells was prevented. 相似文献
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beta-Ionone is found to stimulate considerably carotinoids synthesis in Blakeslea trispora. The stabilization of carotene-synthesizing ability of B. trispora in the presence of beta-ionine under prolonged incubation time is observed. Stabilization of polyribosomes in the presence of beta-ionine is observed when studying polyribosome content in B. trispora. A hypothesis is expressed on the existence of biochemical "receptors" as a linkage between synthesized protein and destroying mRNA. 相似文献
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VA Usmanov 《Canadian Metallurgical Quarterly》1976,70(6):57-63
On the first day of the development of acute coronary insufficiency there appears a spastic state of all the vascular system of the small intestine mesentery and a deceleration of the blood flow. On the third day after ligation of the coronary artery branch against the background of spasmed arterioles the alternation of sites of constricted and dilated capillaries, postcapillaries and venules was observed, i.e., there was a well pronounced spasticatonical state of the microcirculation bed vessels. On the fifth and seventh day the characteristic features were dilatation and decreased tonus of the venous part of the microcirculatory bed, redistribution of blood and more considerable disorders in microcirculation with aggregation and diapedesis of erythrocytes. 相似文献
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VP Chernobrovkin KD Kalantarov VA Sirokvashin EIu El''kind VP me?er 《Canadian Metallurgical Quarterly》1976,21(3):64-68
An index of completion of phagocytosis was studied for staphylococcus cultures of various biological activity in experiments with surviving polymorphonuclear leukocytes. Among the coagulase-forming staphylococci virulent strains proved to be nonviable in a lesser percentage of cases than the avirulent ones. Coagulase- and mannite-negative cultures proved to be most unstable. Staphylococcus toxin depressed the migration of polymorphonuclear leukocytes to the focus of irritation, inhibited ingestion of the virulent, and, to a lesser degree, of avirulent coagulase-forming staphylococci, but failed to influence the ingestion of coagulase-negative epidermal staphylococci. The influence of staphylotoxin on the phagocytosis completion index was either the minimal or absent entirely. 相似文献
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