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31.
探讨肝纤维化形成过程转化生长因子-β及其受体的表达对胶原合成的影响。方法:采用免疫组化和斑点杂交技术,观察实验性大鼠肝纤维化过程肝内TGF-β1,TGF-βRⅡ和Ⅰ、Ⅲ型前胶原mRNA及其蛋白表达的动态变化。结果随着肝纤维化程度的加重,肝内TGF-β1、TGF-βRⅡ和Ⅰ、Ⅲ型前胶原mRNA及其蛋白表达均明显增加,组间比较均有显著差异(P〈0.05或P〈0.01)。TGF-β1与Ⅰ、Ⅲ型前胶原mR  相似文献   
32.
目的 :探讨小柴胡汤分解剂在体外及体内抗柯萨奇 B3病毒 (CVB3)及保护心肌细胞的作用。方法 :用小柴胡汤分解剂通过体外微量细胞培养 ,作用于被 CVB3直接损伤的细胞模型及经腹腔感染 CVB3m Balb/ c小鼠心肌炎模型 ,分析不同浓度分解剂的效应。结果 :在体外细胞上分解剂 A、B液自 1∶ 32稀释度对 vero细胞的毒性作用已丧失 ,至 1∶ 2 5 6稀释度时 ,仍能对抗 CVB3对细胞致病变作用。在体内分解剂 A、B液治疗组小鼠 35只 ,心肌炎发生率 37.14% ;而 2 0只对照组小鼠心肌炎发生率 5 9.1% ,两者有显著性差异 (χ2 =4.6 8,P <0 .0 5 ) ,在预防给药组更为明显 (P <0 .0 1)。结论 :小柴胡汤分解剂 A、B液在体内、体外均具有抗病毒及保护心肌的作用。  相似文献   
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Aneurysm of sinus of Valsalva dissecting into interventricular septum is a rare entity. We report one such case who was incidentally diagnosed by echocardiography to have this abnormality during evaluation of a clinically suspected isolated aortic regurgitation.KEY WORDS: Aneurysm – dissecting – sinus of Valsalva, Echocardiography  相似文献   
37.
Data from analgesic clinical trials have characteristics such as ordered categorical longitudinal responses with repeated measures, delay of effect with respect to analgesic plasma concentration, and right-hand censoring of response due to remedication. In order to determine the concentration-effect relationship of such data, we propose convolving an empirical function for plasma concentration, in the form of broken lines which connect each pair of neighboring observations, with a monoexponential function, to generate effect site concentration Effect site concentration and time are used, simultaneously, as independent variables in the fit of the model for the logit of the probability of having a specific pain relief (PR) score at each time point pre-remedication, via maximum likelihood. Using corresponding effect site concentration, the probabilities of having specific PR scores post-remedication are predicted via the concentration-response relationship established. The overall (pre- and post-remedication) predictions and corresponding standard errors for the responses are then estimated. Inference of the PR scoring, using a posterior method, is proposed. An illustration using real data is used to demonstrate these methods.  相似文献   
38.
Design and use of internal receiver coils for magnetic resonance imaging   总被引:2,自引:0,他引:2  
This review describes coils for MRI that are inserted into the body through natural orifices. It covers the design and implementation of small internal receiver coils for use in the pelvis and gastrointestinal tract. Normal anatomy delineated by the high resolution obtained by using these coils and the appearances in a number of disease states for each clinical application are described.  相似文献   
39.
Even at an early stage, hepatocellular carcinoma (HCC) in patients with cirrhosis is often deemed unresectable because of limited liver reserve. In these circumstances, liver transplantation (LTx) offers some hope for palliation or cure. The results of LTx for selected cirrhotic patients with HCC were analysed. The outcomes were compared with those of patients who underwent LTx for other forms of hepatic malignancy and those who underwent LTx for non-malignant conditions. Four hundred and eighty LTx were performed in 441 patients between January 1986 and December 1998. Twenty-eight LTx recipients (25 males, 3 females) of mean age 51 (14 63) yr had cirrhosis and HCC. Twenty-seven patients had underlying predisposing conditions (11 had hepatitis B, 10 had hepatitis C, 2 had hepatitis B and C, 1 had haemochromatosis, 1 had autoimmune hepatitis, 1 had alcoholic cirrhosis and 1 had alpha-1 antitrypsin deficiency). In 22 patients, HCC was diagnosed pre-LTx, and in 6 patients, the cancers were discovered incidentally. The average tumour size and number were 2.8 (0.4-11.5) cm and 1.3 (1-4), respectively. Two patients with known HCC died during and shortly after the LTx operation. Of the other patients, 3 died; 1 died of HCC recurrence 18 months post-LTx, 1 died of graft failure from recurrent hepatitis C and 1 died of fungal sepsis. Twenty-three (82%) patients survived to 22.5 (0.5-96) months post-LTx without HCC recurrence and with 1- and 3-yr actuarial patient survival rates of 87 and 76%, respectively. Equivalent survival rates of patients who underwent LTx for other malignancies (n = 11) were 82 and 46% (p = NS), and for those who underwent LTx for benign causes (n = 402), they were 77 and 73% (p = NS). All 15 patients with known HCC, who met the selection criteria now in use, survived. LTx can result in prolonged. cancer-free survival in a good proportion of patients with cirrhosis and HCC, particularly when the cancers are incidental, or when diagnosed pre-LTx, conforming to established selection criteria. An active LTx programme for this group of patients is justified.  相似文献   
40.
晚期肺癌73例外科治疗分析   总被引:1,自引:0,他引:1  
目的 总结近9a实施的肺癌手术203例,其中属于Ⅲb或Ⅳ期的晚期肺癌73例,旨在讨论晚期肺癌的手术指征,手术操作要点。方法 行全肺切除18例(左肺15例,右肺3例),肺叶切除54例,肺癌切除后复发余肺切除1例,经心包内处理肺血管17例,合并民房部分切除2例;支气管成形术13敢管隆凸成形术1例。结果 除1例因急性呼吸功能衰竭导致死亡外,其余均临床治愈,术后生存率1a内为95%,1a以不足2a为80%  相似文献   
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