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71.
A significant decline of CD3 cell detected by rosettes and a significant increased of B cell populations were observed. The total CD3+, helper CD4+ and suppressor CD8+ T-cell subsets showed no significant variation em relation to sex, age thymectomy and corticotherapy by monoclonal antibodies.  相似文献   
72.
73.
The role of donor and recipient factors in initial renal graft non-function   总被引:1,自引:0,他引:1  
ATN is a deleterious problem in the outcome of kidney transplantation. This complication is usually related to multiple factors including donor parameters, surgical technique, ischemic time, and recipient variables. In order to develop prophylactic measures, out of 430 kidney transplants performed in our Department, a series of 90 consecutive cadaveric renal allografts has been considered in this study. The overall incidence of IGNF was 23/90 (25.5%). Kidneys from MOD revealed a lower rate of IGNF (7/35 = 20%) when compared with organs from SOD (16/55 = 29%, P = NS). No difference was noted when kidneys were removed together with heart and/or liver and/or pancreas. Out of the donor factors, only CID was significant (17 +/- 9 hours in IGNF v 11 +/- 10 hours in patients with IGF, P = less than .05). Analysis of data concerning the fate of paired kidneys revealed two cases of IGNF in both kidneys from the same donor v 14 cases of IGNF in only one of the two paired grafts (P = NS). We conclude that: 1. Donor factors are clearly associated with a minority of IGNF. 2. The introduction of multiorgan procurement programs does not complicate early function. 3. Recipient factors (immunological events and intraoperative fluid management) provides important additive effects on initial graft nonfunction.  相似文献   
74.
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata.  相似文献   
75.
The EUROCAT programme is a concerted action of the European Economic Community for the epidemiologic surveillance of congenital anomalies. Surveillance is based on a network of regional registries coordinated by a central registry. The programme started in 1979 and by 1987, 23 centres were participating, covering together more than 300,000 births per year. The surveillance process implies the selection of the anomalies possibly associated with environmental teratogens or mutagens, the definition of abnormal variations in the rate of these anomalies (the alarms), the establishment of base-line rate and the continuous monitoring of rate. The programme is evaluated by reference to four criteria: the sensitivity of the system in detecting teratogens or mutagens, the specificity of alarms, the rapidity in warning of alarm and in investigating their causes, and the programme efficiency expressed as its cost-utility ratio.  相似文献   
76.
The paper demonstrate the surgical approach used by the authors to implant the AMS 700CX penile prosthesis. Pre- and postoperative management are also discussed.  相似文献   
77.
Some studies on energy metabolism of men and women in Third World countries suggested that their basal metabolic rate (BMR) is lower compared to BMRs of people in Northern European and American countries. It is, however, not clear whether this results from ethnic factors, climate or adaptation to, for instance, a low energy intake. A study on energy requirements of people from Third World countries has therefore been performed. People with different ethnic backgrounds participated; they were divided into four ethnic groups: 8 African males, 7 Asian males of Mongolian origin (Asian-M), 8 Asian males of Caucasian origin (Asian-C) and 7 European males, who formed the control group. The participants from outside Europe had spent at least 3 months in the Netherlands. All participants consumed a diet (12 per cent of energy from protein, 22 per cent from fat and 66 per cent from carbohydrate) during 8 d. The dietary energy given to each individual was estimated to maintain energy equilibrium during the experiment. The last 3 nights and 2 days were spent in an indirect whole-body calorimeter. Two 24-h energy expenditure (24hEE) measurements were performed on each subject. The environmental temperature inside the calorimeter was 22.0-24.5 degrees C. Physical activity was light, mainly sedentary, with 75 min bicycling at 15 W. The Asian subjects had a significantly lower body weight and fat-free mass than the Europeans. Energy requirement (ER), 24hEE and EE during the night (8 h sleep) was lower in the Asian and African subjects compared to the Europeans, but the difference only reached significance for the Asian-C and African males. When ER, 24hEE and EE-night were expressed in relation to body weight and fat-free mass the Asian groups showed a higher ER and higher EE than the Europeans. This result is contrary to findings of others and may be caused eg, by a higher body weight and fat-free mass of the European controls. Comparison of EE-night with BMR estimated from FAO/WHO/UNU equations showed that the EE-night was consistently lower by about 9 per cent. This suggests that EE during the night may not be predicted by the BMR estimated by widely used equations. This study does not give conclusive evidence that an ethnic factor is involved in energy metabolism in humans.  相似文献   
78.
79.
The neutrophil (PMN) receptor for formylated peptides such as N-formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP) is involved in binding and subsequent response to certain chemotactic stimuli. The receptor on human PMN has been reported to consist of several glycoprotein components, ranging in size from 43-94 kDa. Furthermore, FMLP receptors on human PMN have been shown to contain both high and low affinity states. In this study, the receptor was purified by subjecting solubilized PMN plasma membrane components to FMLP-affinity chromatography, and was found to be comprised of four components, one of 68 kDa, and the others of 94, 48, and approximately 40 kDa. Only the 68, the 94, and the approximately 40 kDa components specifically bound a radioiodinated FMLP analogue. To further characterize these components, a battery of monoclonal antibodies reactive against the FMLP receptor was prepared. Seven monoclonal antibodies were selected on the basis of their reactivity with the 68 kDa receptor component. Some of these antibodies also cross-react with the 48 kDa component, suggesting that the 68 and the 48 kDa receptor moieties are immunologically related. These antibodies reacted with normal human neutrophils, but not with lymphocytes, or unstimulated HL-60 cells. Furthermore, the presence of 20 nmol of FMLP inhibited the binding of five of the anti-receptor antibodies to whole PMN. These results suggest that the epitopes recognized by these five antibodies may possibly be involved in FMLP binding.  相似文献   
80.
The time-dependent release by human alpha-thrombin of the physiological variants of fibrinopeptide A, i.e. fibrinopeptide A-3-phosphate (FPAP) and des-Ala-fibrinopeptide A (FPAY), has been measured in order to study the kinetic pathway for their hydrolysis. The best-fit kinetic model for the release of FPAP and FPAY is consistent with a simple pseudo first-order reaction, as observed with FPA. These findings indicate that FPAP and FPAY are also released from intact fibrinogen before release of FPB. The values of the specificity constants, i.e. k(at)/Km, for the enzymatic reaction between thrombin and the various alpha-chains showed that AP alpha- and AY alpha-chain are hydrolyzed with a 0.2-and 0.4-fold higher specificity constant respectively than that of A alpha-chain. Such minor differences observed with the various chains suggest that the 1-3 NH2-terminal residues of the chain do not significantly contribute to the catalytic efficiency of thrombin toward the alpha-chains of fibrinogen.  相似文献   
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