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11.
BACKGROUND: The precise mechanisms involved in islet xenograft rejection remain unknown. The purpose of the present study was to determine cellular mechanisms responsible for islet xenograft rejection in the liver to facilitate finding a procedure for prevention of immune rejection. METHODS: Hepatic mononuclear cells (MNC) as well as splenocytes, peripheral blood MNC, and thymocytes from streptozotocin-induced diabetic mice (BALB/c) rejecting the intrahepatic rat (Lewis) islet xenografts were isolated and examined by two-color FACS analysis. RESULTS: The characteristic finding of the hepatic MNC from the mice rejecting islet xenografts compared with mice receiving isografts was a significant increase in the yield as well as in the percentage of the cells expressing CD3+ interleukin-2 receptor (IL-2R) alpha- beta+, CD3+ CD8alpha+ beta+, and T cell receptor (TCR) alphabeta+ lymphocyte function-associated antigen-1+. The expression of CD3 and TCR alphabeta of these T cells was found to be of intermediate intensity (TCR(int) cells). The expansion of these TCR(int) cells occurred predominantly in the liver. There was no significant difference in the cells expressing CD3+ IL-2R alpha+, CD3+ CD4+, CD3+ TCRgammadelta+, CD3- IL-2Rbeta+ (natural killer cells), and B220+ (B cells). In vivo administration of anti-IL-2Rbeta monoclonal antibody directed to the expanded cells produced a prevention of rejection. CONCLUSIONS: These findings suggest that islet xenograft rejection in the liver from rat to mouse is an event for which the TCR(int) cells are responsible.  相似文献   
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AIM: This study of trimetasidine effects on plasmic hemostasis and blood biochemistry in patients with chronic heart failure (CCF) of NYHA functional class II-III. MATERIALS AND METHODS: This study enrolled 30 patients (24 males and 6 females) aged 40-72 years with class II-III CCF, postinfarction cardiosclerosis and ejection fraction under 40%. Previously the patients received perindopril (the inhibitor of angiotensin converting enzyme) in daily dose 2-4 mg, on-demand digoxin and diuretics. Trimetasidine was given in a daily dose 60 mg for 6 months. Before and after the treatment the patients' blood was examined for: levels of factors VII and X of antithrombin III coagulation, soluble fibrinomonomeric complexes (SFMC), fibrinogen, glucose, uric acid, creatinines, total cholesterol, high density lipoprotein, triglycerides, AST, ALT, LDH, acid phosphotase, gamma-GT, sodium, potassium, activated partial thrombin time. RESULTS: Initially, the patients had a 23.9% increase in the levels of factors VII and X, a 14.3% decrease of antithrombin III, 29.8 and 227.6% rise in concentrations of fibrinogen and SFMC, respectively, compared to controls. Aftertreatment values of fibrinogen, factors VII and X, SFMC fell by 21.1, 17 and 35.5%, respectively. The thrombin time arose by 17.9% (p > 0.05). Insignificant inhibition was registered in the activity of acid phosphotase and gamma-GT. Glucose, AST, ALT, LDH levels remained unchanged. Plasma creatinine tended to lowering. Total cholesterol insignificantly increased at high levels of HDL cholesterol (p > 0.05) and reduced levels of triglycerides (p > 0.05). CONCLUSIONS: Trimetasidine therapy, given after conventional treatment with diuretics, digoxin, inhibitor of angiotensin-converting enzyme, aspirin has a beneficial effect in patients with circulatory deficiency through improving hemostatic and biochemical parameters.  相似文献   
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Palladium was deposited galvanostatically and potentiostatically from complex chloride solutions at various cds and potentials. The properties of the deposits were studied by a number of methods. The roughness measured with a mechanical profilometer strongly increased upon reaching the limiting cd in agreement with the general theory of the influence of mass transport control on the electrodeposition of metals.The particle size of the Pd-powders obtained above the limiting cd decreased steadily with increasing current density of deposition. In contrast to this, the BET-surface area as well as the catalytic activity (determined by measuring the acceleration of the rate of hydrogenation of cyclohexene) went through a maximum. The latter occurs in the region where the deposit consists of both the α and β H-Pd phases.The metal was deposited on a Pd-electrode as well as on a suspension of active carbon. The maximum catalytic activity was in both cases comparable to that of a non-electrolytic Pd-test catalyst.  相似文献   
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Using the Scatchard analysis of 125J-EGF binding it was shown that plasma membranes of gastric and small intestinal epithelial cells contain approximately 20 times less EGF-receptors (EGF-R) than liver cells. Investigation of the phosphorylation activity of EGF-R-kinase was performed in vitro on plasma membranes from intestine, intestinal tumours and liver cells. The main protein phosphorylated at tyrosine in the tumours was p34 but the intensity of EGF-R autophosphorylation and its total protein-tyrosine kinase activity were reduced (as compared with small-intestinal and liver cell membranes). In the tumours of the colon induced by DMH an increased binding of 125J-EGF has been observed as compared with normal colonic enterocytes and increased number of EGF-R was clearly demonstrated. Phosphorylation of p34 in the intestinal membranes proceeds much more intensively than that of EGF-R.  相似文献   
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OBJECTIVES: The association of anti-HBs immunoglobulins and anti-HBV vaccine could increase the immunogenicity of the latter. The aim of this prospective randomized trial was to compare the immunogenicity of anti-HBs vaccination and serovaccination in alcoholic patients with cirrhosis. METHODS: Alcoholic patients with cirrhosis were randomized in 2 groups: a) Vaccination group: 3 i.m. injections of GenHevac B followed by one booster at month 9; b) Serovaccination group: same vaccination schedule followed by one i.m. injection of anti-HBs immunoglobulins (500 IU). RESULTS: Twenty-five patients (17 males and 8 females, mean age 56 years) were included in the study: 13 received a vaccination and 12 received a serovaccination. After 12 months, the seroconversion rates were 69% and 67% in vaccination and in serovaccination groups, respectively. The predictive factors of non responsiveness were as following: Child B cirrhosis, low number of CD8, a high CD4/CD8 rate, the existence of HLA DR7 antigen, and the absence of HLA DR1 antigen. CONCLUSION: In alcoholic patients with cirrhosis, serovaccination does not increase the immunogenicity of anti-HBs vaccination and should not be recommended.  相似文献   
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The classic conservative approach for thermal process design can lead to over-processing, especially for laminar flow, when a significant distribution of temperature and of residence time occurs. In order to optimize quality retention, a more comprehensive model is required. A model comprising differential equations for mass and heat transfer is proposed for the simulation of the continuous thermal processing of a non-Newtonian food in a tubular system. The model takes into account the contribution from heating and cooling sections, the heat exchange with the ambient air and effective diffusion associated with non-ideal laminar flow. The study case of soursop juice processing was used to test the model. Various simulations were performed to evaluate the effect of the model assumptions. An expressive difference in the predicted lethality was observed between the classic approach and the proposed model. The main advantage of the model is its flexibility to represent different aspects with a small computational time, making it suitable for process evaluation and design.  相似文献   
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