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991.
胸腺免疫抑制组分的抗变态反应作用   总被引:1,自引:0,他引:1  
整体实验表明,胸腺免疫抑制组分肌内注射1wk对大鼠被动皮肤过敏反应(8、20、50和125mg·kg-1)兔Arthus反应(4和12mg·kg-1)均有明显的抑制作用。体外实验表明,该药能抑制致敏豚鼠离体回肠平滑肌的过敏性收缩,IC50为446.7mg·L-1。上述结果表明,胸腺免疫抑制组分有抗Ⅰ和Ⅲ型变态反应的作用。  相似文献   
992.
依沙吖啶引产失败后用卡前列甲酯栓的疗效   总被引:2,自引:1,他引:1  
目的:观察35例中期妊娠用依沙吖啶1次羊膜腔注射引产失败后,再用卡前列甲酯栓的效果。方法:卡前列甲酯栓1mg,放置于阴道后穹窿,若3h后无宫缩,再放1次。结果:35例孕妇引产成功率100%。引产后24h内阴道流血量200±20mL。出现腹泻,恶心等不良反应各1例。结论:卡前列7甲酯栓用于对依沙吖啶中期引产失败后效果满意。  相似文献   
993.
One year prevalence rates far psychoactive substance use are reported based on a community survey in Hunan, Helongjiang and Jiangsu. Data were gathered on more than 14 000 respondents (15–65 years old). The drinking rates ranged from 58.3% to 82.6% for men and from 16.3% to 31.4% for women. Smoking rates ranged from 64.9% to 68.1% for men and from 0.1% to 20.5% for women. Most drinkers were light users and most smokers were heavy users, Illicit drug use was found in the Hunan site. For both frequency and quantity of psychoactive substance use, women are lighter consumers than males (except for the use of minor tranquilizers and analgesics). Psychosocial factors related to drinking and smoking are also investigated in this study.  相似文献   
994.
Spontaneous ovarian hyperstimulation mimicking an ovarian tumour   总被引:1,自引:1,他引:0  
Ovarian hyperstimulation syndrome in a spontaneous singletonpregnancy is exceedingly rare. We report a case of ovarian hyperstimulationpresenting as bilateral ovarian masses in association with spontaneouspregnancy, occurring in a woman with disturbed liver function.A possible mechanism is discussed.  相似文献   
995.
创面异体移植培养表皮细胞后存活的判定   总被引:1,自引:0,他引:1  
应用4种方法判定烧伤创面异体移植的培养表皮细胞存活情况:1.聚合酶链反应(PCR)查Y染色体特异性DNA片段;2.PCR扩增PMCT118长度多态性基因位点;3.PCR/SSOHLA-DQa分型;4.DNA指纹。共检测16例病人的27个活检标本,均证实有供者的DNA,最长时间为移植后92天。初步实验结果表明:培养表皮异体移植后可存活较长时间。  相似文献   
996.
采用微波炉中的谐振场和外辐射天线的平面波对冻存在-196℃的活细胞进行复温试验。结果表明:谐振场加温迅速但极不均匀,造成细胞大量死亡。平面电磁波微波泄漏大,效率低,加温时间过长,不能应用。本文阐述了微波对超低温细胞复温的可能性和现有微波仪不宜进行细胞复温的原因,并提出改进设计的建议。  相似文献   
997.
The time-dependent effects of Klebsiella pneumoniae endotoxin on hepatic cytochrome P450-dependent drug-metabolizing capacity (cytochrome P450 and b5 content, activity of aminopyrine N-demethylase, p-nitroanisole O-demethylase, aniline hydroxylase and benzphetamine N-demethylase) and on the pharmacokinetics of antipyrine have been determined in rats. Measurement of enzyme activity and antipyrine (after intravenous injection of 20 mgkg?1) were performed 2, 24 and 96 h after a single intraperitoneal injection of endotoxin (1 mgkg?1) and after repeated doses (once daily for 4 days). The contribution of tumour necrosis factor α (TNFα) to the endotoxin-induced changes was also examined in rats pretreated with granulocyte colony-stimulating factor (G-CSF). The systemic clearance of antipyrine and the activity of hepatic cytochrome P450-dependent drug-metabolizing enzymes were dramatically reduced 24 h after a single injection of endotoxin, but had returned to control levels by 96 h. The magnitudes of these decreases in these measurements after repeated doses of endotoxin were similar to those seen 24 h after the single dose. The systemic clearance of antipyrine correlated significantly with cytochrome P450 content and aminopyrine N-demethylase activity. In histopathological experiments, moderate hypertrophy of Kupffer cells was observed, with no evidence of severe liver-tissue damage. G-CSF pretreatment suppressed the increased plasma concentrations of TNFα produced 2 h after single endotoxin injection, but did not eliminate the endotoxin-induced decrease in the systemic clearance of antipyrine, suggesting that TNFα is not the sole component responsible for the reduction of cytochrome P450-mediated drug-metabolizing enzyme activity. These results provide evidence that a single intraperitoneal injection of 1·0 mgkg?1 K. pneumoniae endotoxin in rats reduces hepatic P450 and b5 levels, and reduces the activity of various cytochrome P450-mediated drug-metabolizing enzymes without causing severe liver-tissue damage. This suggests that the effect of endotoxin on hepatic cytochrome P450-mediated drug-metabolizing isozymes is non-selective.  相似文献   
998.
We have constructed a series of retroviral vectors in which the expression of antisense RNA targeted at the full length coding sequence of HIV-1 tat or rev was driven by three different promoters and in the context of double-copy or single-copy vectors. Jurkat cells transduced by these vectors were shown to express the expected tat or rev antisense RNA without alteration in cell proliferation or surface CD4 expression. After challenge with HIV, four patterns of protection were identified, with the degree of protection being determined primarily by the design of the expression system. In those patterns showing long-term complete protection, we could detect no HIV p24 in the culture supernatants or in the cells, and no HIV RNA or HIV proviral DNA (by PCR), during a 23-week follow-up. Experiments designed to rescue any live virus still formed in the culture after 20 weeks’ challenge demonstrated that, with some constructs, infectious virus could no longer be isolated, while with other constructs, only a low level of infectious virus was still being formed and providing a continuing virus challenge, although all other markers of infection remained undetectable. Our results demonstrated that antisense RNA expression driven by tRNA promoter in the context of a double-copy vector conferred better long-term protection against HIV infection compared to that driven by HIV LTR or MLV LTR promoters, and that the optimized vectors may be useful in developing a gene therapy against HIV-1 infection and AIDS.  相似文献   
999.
目的 探究扩散加权成像(diffusion weighted imaging, DWI)、体素不相干运动扩散加权成像(diffusion-weighted imaging of voxel incoherent motion, IVIM)参数与脑胶质瘤患儿肿瘤标志物水平相关性及诊断价值。方法 选取于我院进行诊断的疑似脑胶质瘤患儿89例,以病理检查为金标准,最终确诊脑胶质瘤患儿62例为观察组,其余27例为对照组。所有研究对象均进行DWI技术、IVIM技术检查,酶联免疫吸附实验法检测糖链抗原125(carbohydrate antigen 125,CA125)、表皮生长因子(epidermal growth factor, EGF)、癌胚抗原(carcinoembryonic antigen, CEA)水平,对比不同病情患儿表观弥散系数(apparent dispersion coefficient, ADC)、相对脑血容量(relative cerebral blood volume, rCBV)、真实水分子弥散系数(true water molecular dispersion coe...  相似文献   
1000.
目的 探讨可溶性白细胞分化抗原14(soluble cluster of differentiation antigen 14,sCD14)、血管生成素2(angiopoietin 2,Ang2)、C反应蛋白(C-reactive protein,CRP)与急诊创伤骨折伴多发伤患者病情转归的关系及意义。 方法 选取创伤骨折伴多发伤患者324例,根据患者出院时病情转归情况分为良好组(275例)、不良组(49例),比较2组一般资料、sCD14、Ang2、CRP水平,应用Pearson分析sCD14、Ang2、CRP与损伤严重程度评分(injury severity score,ISS)关系,采用Cox回归分析急诊创伤骨折伴多发伤患者病情转归的相关影响因素,采用受试者工作特征曲线(receiver operating characteristic,ROC)分析sCD14、Ang2、CRP对病情转归预测价值。 结果 不良组ISS评分高于良好组(P<0.05);不良组sCD14、Ang2、CRP高于良好组(P<0.05);sCD14(r=0.785)、Ang2(r=0.778)、CRP(r=0.842)与ISS评分呈正相关(P<0.05);sCD14、Ang2、CRP均是预后相关独立危险因素(P<0.05);sCD14、Ang2、CRP预测病情转归的ROC下面积(area under the curve,AUC)依次为0.813、0.757、0.749;挑选出预测敏感度最高(sCD14)、特异度最高(Ang2)的两个指标进行sCD14+Ang2的联合ROC分析显示,两者联合预测病情转归的AUC为0.935,大于任一单一指标(P<0.05)。 结论 sCD14、Ang2、CRP与急诊创伤骨折伴多发伤患者病情严重程度及病情转归有关,均可作为预测病情转归的标志物,但联合检测sCD14、Ang2能提高预测可靠性,为临床诊疗及护理提供更准确的参考信息。  相似文献   
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