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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
104.
CT scans of 9 patients with orbital pseudotumor (bilateral in 6 and unilateral in 3) showed findings distinct from those observed in Graves' ophthalmopathy. In bilateral involvement, they ranged from localized mass lesions to complete obiliteration of normal orbital CT anatomical landmarks; diffuse or multifocal lesions involving the posterior globe and muscle insertions were most typical of the diagnosis. However, findings in unilateral psedotumor may be indistinguishable from orbital mass lesions other than Graves' ophthalmopathy. Serial CT scans were used to show progression of disease and response to treatment. 相似文献
105.
Resolution of human auditory analyser to tine-impulse signals in the noise has been studied AX method was put in the basis of the experiment. Signals were the sinusoid intercepts. Relationships between probability of erroneous distinguishing of the signals and untuning, signal/noise and number of periods in the frequency range from 150 to 4800 Hz. It has been shown that the accepting auditory properties are invariants to the time transformations, the wave number of the sinusoid being the determining characteristics of the stimulus. A concept of frequency--time band of the auditory system is introduced. Its width according to the experimental data depends on the signal/noise ratio. 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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A simple, accurate method for demonstrating very small areas of endothelium is described. Some possible fields for further investigation are suggested. An outline of the possible normal mechanism of endothelial regeneration is described. 相似文献
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