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The authors review the results of estimating platelet spontaneous aggregation by Wu and Hoak's method and by its modifications. They describe a modification of the procedure that essentially improves the accuracy of investigation, is sufficiently sensitive, simple, and rapid. Its informative value was confirmed in experiments with spontaneous platelet aggregation in rabbits with cholesterolemia.  相似文献   
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Study of the immunologic reactivity of 104 patients with chronic obstructive bronchitis revealed the deficiency of cellular immunity for the most part. The use of timoptin, sodium nucleinate and their combined application raised the clinical efficacy of the treatment of patients with chronic obstructive bronchitis, significantly reduced the concentration of medium-weight molecules in blood serum, and corrected immunity disorders.  相似文献   
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Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports. While at week 5 of gestation inhibin-A, activin-A and follistatin concentrations were similar to those at the follicular phase, all three increased progressively (P < 0.001) to maximal concentrations in week 36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately 22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/- 418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174 pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was undetectable (<12 pg/ml) between week 5-16 of gestation but increased slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was undetectable throughout pregnancy. Post-partum concentrations of inhibin-A (41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml), pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were substantially lower than at week 36 of gestation. The activin-A:follistatin ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more free activin-A is available in the maternal circulation during late pregnancy.   相似文献   
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Light and electron microscopy, histochemistry, histoautoradiography and vital staining were used to assess changes occurring in subcutaneous connective tissue surrounding a DMBA-containing pill in rats, samples being obtained at 2-week intervals until malignant fibrous histiocytoma became apparent. Initial tumor lesions developing against the background of alterative-inflammatory and reparative changes included apparently atypical pleomorphic cells showing cytologic signs of malignant transformation which remained virtually unchanged in developed sarcoma. The study, therefore, failed to identify the stage of "presarcoma". A complex of morphologic and functional characteristics of the atypical cells revealed their fibroblastic nature. Progression of tumor was associated with appearance of cells of histiocytic pattern (as evidenced by high activity of acid phosphatase and non-specific esterases, thin villus-like outgrowths of cellular membrane and well-developed Golgi complex) which pointed to pronounced structural and functional variability of poorly-differentiated neoplastic fibroblasts. Tumor revealed xanthomatous and multinuclear giant cells, too. Malignant fibrous histiocytoma is, therefore, poorly-differentiated polymorphocellular sarcoma of fibroblastic origin.  相似文献   
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