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1.
There is a large body of evidence for the role of thymosin peptides in immunogenesis and immunity. In this paper we report on the influence of prothymosin alpha 1 (ProT-alpha 1), a hormone-like peptide derived from the calf thymus, on humoral and cellular immune reactions in the rat. Young adults received intraperitoneal injections of ProT-alpha 1 in the periods before and after immunization with cellular and soluble antigens. ProT-alpha-treatment produced a dose-dependent increase of both humoral and cell-mediated immune responses. The thymus weight increased but not that of spleen. Treatment of nonimmunized rats with this polypeptide significantly elevated the number of CD4+ and decreased the number of CD8+ cells in the peripheral blood. The results suggest a potent immunostimulatory activity of ProT-alpha 1 and imply direct action of this polypeptide on T lymphocytes.  相似文献   
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Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning. We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to PTA.  相似文献   
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The Hemopump Cardiac Assist System is a relatively new intraarterial, axial-flow circulatory assist device that offers temporary left ventricular support to patients in refractory cardiogenic shock, without requiring major surgery for insertion. Use of the Hemopump is associated with a low complication rate. Device-related morbidity is extremely rare. Because the Hemopump is safe for use in community hospitals, the number of patients supported by this device is expected to increase. In this report, we present general guidelines for the care of patients supported by the Hemopump. We describe techniques for the management of afterload reduction, supravalvular dislodgement, device malfunction, ventricular ectopy, intracardiac shunting, and inflow cannula obstruction.  相似文献   
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We have studied the effect of soman intoxication on serum acute phase reactants (APR) levels, and the relationship of the APR and corticosterone concentrations and the immunosuppressive activity of the serum. One day after the injection of 1.8 LD50 soman the concentrations of 2-macroglobulin (2-MG) and 1-acid glycoprotein (AGP) in the serum of antidote protected rats increased 4- and 7-fold, respectively, whereas those of hemopexin (Hx), haptoglobin (Hp) and cysteine protease inhibitor (CPI) were two to three times higher than in the controls. A similar magnitude of increase of serum acute phase reactants levels was observed when 0.3 LD50 soman was administered at 24-h intervals over the 5-day period. The relationship of changes in the APR concentration, corticosterone level and immunosuppressive activity of the serum was also comparable to that observed in the acute phase response to tissue injury.  相似文献   
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Adrenocorticotrophic hormone (ACTH) is essential for developmental maturation of numerous organ systems during the fetal period and for adaptation to environmental challenges. Immunocytochemical and stereological methods were used in the present study to examine the effects of dexamethasone (Dx) administration during pregnancy on fetal rat pituitary ACTH-producing cells. Doses of 0.5, 0.5 and 1.0 mg Dx/kg body weight/day were given to the dams on 3 consecutive days starting on day 16 of gestation. Morphometric analysis of the ACTH-producing cells of fetuses at 21 days of gestation revealed significant inhibition by 24% and 27%, respectively, of cell volume and cell number after maternal Dx administration, whereas the volume of cell nuclei and volume density of ACTH-stained cells were insignificantly decreased. Immunocytochemical analysis showed reduced numbers, sizes and immunopositivity of ACTH cells of 21-day-old fetuses from Dx-treated dams as compared with the control group. Maternal Dx treatment in the period of intense differentiation of the hypothalamo-hypophyseal-adrenal system had an inhibitory effect on fetal function and proliferative activity of ACTH-producing cells at 21 days of gestation. Thus, inhibition of activity of fetal ACTH-producing cells may lead to adrenal suppression, modified activity of the hypothalamo-pituitary-adrenal axis and reduced body weight possibly causing lasting functional abnormalities.  相似文献   
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