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131.
132.
A new DRB1 allele, DRB1*0902, has been identified in an individual of the Jing ethnic minority. Its sequence was confirmed by sequencing of PCR products and clones. This allele differed by three nucleotides from DRB1*09012 at positions 157, 161 and 166, and resulted in amino acid motif substitution from VAES to DAEY.  相似文献   
133.
The current study tested the hypothesis that circulating atrial natriuretic peptide (ANP) inhibits sympathetic outflow, as reflected in lumbar sympathetic nerve activity (LSNA), in NaCl-sensitive spontaneously hypertensive rats (SHR-S) and that this effect is exaggerated by high NaCl feeding. NaCl-resistant SHR (SHR-R) and Wistar-Kyoto (WKY) rats maintained on basal and high-NaCl diets were used as controls. Intravenous administration of ANP to conscious, freely moving rats with intact baroreflexes decreased blood pressure and LSNA in SHR-S, SHR-R and WKY rats maintained on basal or high-NaCl diets for 2-3 weeks. The depressor response to intravenous ANP was greater in 8% NaCl-fed SHR-S than in any other group; the LSNA response was greater in SHR-S on either diet than in any other group. Intracerebroventricular administration of ANP evoked small, transient sympatholytic responses in SHR-S on both diets and minimal responses in SHR-R and WKY rats; these responses could not be attributed to leakage of ANP into the peripheral circulation. Thus, circulating ANP has a sympatholytic effect in SHR-S that is not amplified by high-NaCl feeding and can be only partially accounted for by a central action.  相似文献   
134.
Subclavian artery lesion that is associated with low complication rate could be treated by percutaneous intervention effectively. However, the success of endovascular therapy for occlusive lesion may be limited by failure to cross with a guidewire. We describe the use of a system using optical coherence reflectometry for navigation and radiofrequency ablation to enable wire passage through subclavian artery occlusion that could not be crossed by conventional guidewires.  相似文献   
135.
Q Chen  P Sun  I Prigione  H Xie  S Ferrini 《Tumori》1992,78(2):79-86
In an attempt to construct bispecific monoclonal antibodies (bimAbs) able to target cytotoxic T lymphocytes against human hepatoma cells, an HGPRT-deficient mutant of the Hepama-6 hybridoma, which produces an antihuman-hepatoma mAb, was directly fused with splenocytes from Balb/C mice immunized by a polyclonal cytotoxic T-cell line. Hybrid hybridomas were selected in HAT medium, and their supernatants were directly screened for the ability to induce IL-2-cultured cytotoxic T lymphocytes to kill hepatoma cells in a 51Cr-release assay. The selected hybrid hybridoma, termed DQ-33, secretes a bimAb, which reacts with a CD3-associated determinant. When resting peripheral-blood lymphocytes were used as effector cells, virtually no cytolytic activity could be induced by DQ-33, whereas phytohemagglutinin-activated lymphocytes that had been expanded in vitro in IL-2-containing medium could be efficiently targeted against hepatoma cells. Targeting by DQ-33 bimAb was analyzed on different subsets of IL-2-cultured lymphocytes. It was evident that CD+4-8+ TCR alpha/beta+ and CD3+4-8-TCR gamma/delta+ lymphocytes were efficiently induced by bimAb to lyse human hepatoma cells, whereas no induction of cytolysis could be observed when CD3 + 4 + 8-TCR alpha/beta+ cells were used as effectors. DQ-33 bimAb was also able to induce lymphokine secretion (IL-2, GM-CSF and TNF-alpha) by all the different subsets of lymphocytes analyzed in the presence of target cells expressing the relevant antigen, independent of the expression of cytolytic activity.  相似文献   
136.
同步记录72例拟诊冠心病患者头胸导联(HC)及常规导联(wilson)心电图(ECG),并与冠脉造影结果对照。结果:HC与Wilson导联ECG对冠心病诊断的敏感性分别为88.9%与81.5%,特异性33.3%与27.8%,准确性75%与68.1%;二组导联对比无明显差异(P>0.05);对右心室梗塞、缺血及左心室后壁缺血.HC导联的敏感性(91.7%)及准确性(94.4%)均显著高于Wilson导联(12.5%、70.8%,P<0.01),并与冠状动脉病变程度呈高度正相关。HC导联优于Wilson导联。  相似文献   
137.
缺锌对大鼠力竭性游泳前后睾酮和锌水平变化的影响   总被引:5,自引:1,他引:4  
本实验动态观察了缺锌和缺锌后补锌对大鼠力竭性游泳前后辜丸和血清睾酮、锌水平以及游泳能力的影响。结果显示:缺锌造成大鼠游泳能力大大降低,补锌后明显增加。不论安静时还是力竭性游泳后12小时内,缺锌大鼠的血清和辜丸锌含量均显著低于对照和补锌大鼠。与对照和补锌大鼠相比,缺锌大鼠的血清和睾丸酮含量,安静时均较低,力竭性游泳后也呈现不同程度的降低。缺锌还造成大鼠辜丸重量的明显下降。结果表明,锌营养不良将损害运动能力。  相似文献   
138.
The biomechanical effects of disc injury on flexion-extension were investigated in nine fresh porcine functional spinal units. Under 12 N-m in extension and 6 N-m in flexion, the range of motion among intact specimens were 23.11 degrees -33.29 degrees (mean = 26.07 degrees , SD = 3.25 degrees ), which shifted to 28.04 degrees -38.46 degrees (mean = 31.69 degrees , SD = 3.50 degrees ) when discs were injured. Similarly, the neutral zones among intact and disc injured specimens were 4.88 degrees -12.75 degrees (mean = 9.32 degrees , SD = 2.60 degrees ) and 9.50 degrees -24.43 degrees (mean = 16.80 degrees , SD = 4.69 degrees ) respectively. To obviate the differences between tested specimens, the changes of neutral zone and the range of motion after disc injury were normalized and expressed as ratios as compared to the same items before disc injury. The neutral zone ratio ranged from 1.29 to 3.18 (mean = 1.87, SD = 0.55, p < 0.01). For range of motion, it ranged from 1.13 to 1.42 (mean = 1.22, SD = 0.09, p < 0.01). The change of flexibility coefficient, however, was statistically insignificant in either flexion or extension. The model presented defines the range of motion, the neutral zone as well as the flexibility coefficient under a specific load. It suggests that major spinal instability can be elicited by a minimum flexion-extension moment, as reflected by a profound change of the neutral zone, after disc injury.  相似文献   
139.
Between March 1984 and February 1991, six orthotopic liver transplantations were performed at the Chang Gung Memorial Hospital in Taiwan. The indications for transplantation were Wilson's disease (5 patients) and biliary atresia (1 patient). Donors and recipients were matched only for size and ABO blood group compatibility, and the recipient operations were performed without the use of a venovenous bypass. Arterial reconstruction was carried out by end-to-end hepatic artery anastomosis (4), thoracic aortic conduit (1), or interposition of an iliac artery graft (1), whereas biliary reconstruction was accomplished by a choledochocholedochostomy using a T-tube stent (4) or a choledochocholedochostomy using an external cholecystostomy without stenting (2). Biliary complications occurred in three patients, and all required additional surgery. The average duration of donor-liver cold ischemia, operating time, and blood loss during surgery were 7 h and 50 min (range, 4.5–9 h), 13.5 h (range, 11.8–17h), and 4,385 ml (range, 750–12,000 ml) respectively. The immunosuppressive regimens included a cyclosporinsteroid combination (n=2) and a triple-drug combination (n=4). All except one of the surviving patients experienced at least one rejection episode that was reversed by a methyl-prednisolone bolus and/or recycle. One patient developed a primary cytomegalovirus (CMV) infection that responded well to Ganciclovir treatment. Two of the patients died, one of injuries sustained in a traffic accident 3 years after transplantation, and the other of massive upper gastrointestinal bleeding. The overall survival value at 3 months was 83%, and the follow-up period ranged from 3 months to 7 years. All of the survivors have achieved complete rehabilitation and currently enjoy an excellent quality of life with normal liver function. Althought the present study involved a small number of cases, our results indicate that liver transplantation can be successfully achieved in a high proportion of patients with acceptable morbidity, mortality, and cost in an Asian setting. The extreme shortage of donor organs is currently the most important obstacle limiting the application of liver transplantation in Taiwan.Presented at The Second International Symposium on Treatment of Liver Cancer. Taipei, 3–4 February 1991  相似文献   
140.
Use of cocaine concurrently with alcohol is prevalent among cocaine addicts. Cocaine has been shown to inhibit phytohemagglutinin- and ConA-induced proliferation of T-lymphocytes, NK cell cytotoxicity, and phagocytic activity of peritoneal macrophages. In some studies no effects of cocaine on the immune response have been observed, although on the contrary, others show it increased the NK cell activity and serum antibody response to T-dependent antigen. Effects of cocaine on the immune system may be mediated by its neurostimulatory action on the hypothalamo-pituitary-adrenal axis. ACTH, beta-endorphine, and corticosterone released under the action of cocaine exert various inhibitory effects on the immune function. We studied the immunotoxic effect of cocaine, combination of cocaine with ethanol, and cocaethylene, a derivative formed from cocaine and ethanol in the body, on the mitogen-stimulated production of cytokines by splenocytes. C57BL mice were injected twice daily with 20 mg/kg cocaine or equivalent dose of cocaethylene and received a liquid Lieber-DeCarli diet containing ethanol (26% of total calories) or isocaloric amount of maltose-dextrin. After 3 weeks of treatment, cocaine and cocaethylene caused a significant decrease of the spleen weight and total number of splenocytes. In splenocytes isolated from the cocaine- or cocaethylene-treated mice, mitogen-stimulated production of gamma-interferon, tumor necrosis factor, and interleukin-2 was suppressed, in all cases more severely when cocaethylene was used. Thus, formation of cocaethylene during simultaneous consumption of cocaine and ethanol may enhance the immunotoxicity of cocaine.  相似文献   
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