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111.
RNA干扰(RNAi)是细胞内由双链RNA诱导降解与其配对的特定mRNA的过程。细胞内双链RNA在酶的作用下,形成20-25碱基大小的小干扰RNA(si RNAs),由si RNAs进一步掺入多组分核酸酶并使其激活,从而精确降解与si RNAs序列相同的mRNA,抑制该基因在细胞内的翻译表达。介绍了RNA干扰的分子机制、制备方法、以及RNA干扰技术在功能基因组学、微生物学、基因治疗和信号转导等研究领域里的应用。  相似文献   
112.
Fan ST  Lo CM  Liu CL 《Annals of surgery》2000,231(1):126-131
OBJECTIVE: To report the authors' experience with living donor liver transplantation in adults using right lobe liver grafts, performed by a modified technique. SUMMARY BACKGROUND DATA: The initial results of seven living donor liver transplants in adults using extended right lobe grafts were satisfactory, but serious complications occurred in two donors, and six recipients required repeat laparotomy. Another 11 similar operations were performed. Further evaluation was made with the aim of improving the postoperative outcome. METHODS: From December 1996 to August 1998, 11 patients underwent living donor liver transplantation using right lobe grafts. The first four patients underwent surgery using methods previously designed and the next seven underwent a modification designed to minimize devitalized tissues on the liver transection surface, improve hepatic venous drainage, and reduce the number of hepatic duct orifices. RESULTS: There were no donor deaths. Donor complications included cholestasis (n = 1) and minor wound infection (n = 1). All the first four recipients required a repeat laparotomy for infected necrotic liver transection surface (n = 1), acute pancreatitis (n = 1), hepatic vein thrombosis (n = 1), and leakage from one of the two bilioenteric anastomoses (n = 1). The patient with hepatic vein thrombosis died. In the last seven recipients, all of whom survived the operation, one required a repeat laparotomy with the discovery of a methicillin-resistant Staphylococcus aureus culture of fibrinous exudate at the left subphrenic peritoneum, and another had right hepatic duct stump necrosis. The latter was likely related to hypovolemic shock secondary to bleeding from the right saphenous vein on removal of a hemofiltration catheter. Comparison of the incidence of repeat laparotomy between the first four and the remaining seven recipients showed a significant trend of improvement. Combining the result of the seven patients reported previously, the improvement in terms of relaparotomy rate is significant. CONCLUSION: With modification of surgical technique, living donor liver transplantation in adults using right lobe liver grafts can become a relatively safe procedure.  相似文献   
113.
目的探讨孤立性纤维性肿瘤(SFT)的临床病理、免疫组化特征及鉴别诊断。方法报道一例肺的孤立性纤维性肿瘤,结合文献对本病的临床病理学特征进行探讨。结果临床主要表现为逐渐加重的胸闷、气急。X线胸片显示右下肺有一团块状阴影,边界清。肿瘤呈结节状,位于右下肺,紧靠肺膜下10cm×8cm×7cm,切面灰白,质嫩。镜下:肿瘤主要由短梭形细胞构成,有多种排列方式。免疫组化CD34阳性。结论SFT是一种少见的间质源性的梭形细胞肿瘤,须与多种其它梭形细胞肿瘤进行鉴别,免疫组化有助于鉴别诊断。约10%~30%的SFT具有恶性的生物学行为,表现为局部复发或远处转移,其组织构象并不能完全预测其预后,患者术后定期随访是必要的。  相似文献   
114.
波依定与洛汀新治疗不同中医证型高血压疗效比较   总被引:6,自引:0,他引:6  
目的:观察波依定与洛汀新对不同中医证型高血压的疗效是否具有中草药的某些特征,能否按中医辨证选择抗高血压药.方法:按照WHO的标准明确高血压诊断与分级,根据<中药新药临床研究指导原则>分为4型.216例患者随机分为两组,分别给予波依定与洛汀新治疗,疗程4周.分析对总体血压和不同证型血压的影响,以及对不同症状的疗效有无差异.结果:两种药物降低患者总体血压的幅度基本相同;但分层研究,对4种中医证型患者的血压的降低程度明显不同,洛汀新对肝火亢盛型血压降低幅度更明显,波依定对痰湿壅盛型比其它三型降压更好;对阴虚阳亢型和阴阳两虚型两组之间差异无显著性.对各种证型症状的改善作用也显示同样的结果.结论:抗高血压药对不同中医证型高血压的疗效不同,表明西药也同样具有中草药的某些特性,可以根据中医辨证选择抗高血压药.  相似文献   
115.
PURPOSE: Prostate-specific membrane antigen (PSMA) is a cell surface protein that is overexpressed in prostate cancer, including hormone-refractory and metastatic disease. Our goal in this study was to develop a series of PSMA-based imaging agents for clinical use. EXPERIMENTAL DESIGN: We have synthesized and evaluated the in vivo biodistribution of two radiolabeled urea derivatives that have high affinity for PSMA in severe combined immunodeficient mice harboring MCF-7 (breast, PSMA-negative), PC-3 (prostate, PSMA-negative), and LNCaP (prostate, PSMA-positive) xenografts. Radiopharmaceutical binding selectivity and tumor uptake were also evaluated in vivo using dedicated small animal positron emission tomography, single photon emission computed tomography, and gamma scintigraphic imaging devices. N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-[(11)C]methyl-L-cysteine ([(11)C]DCMC K(i), 3.1 nmol/L) and N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-[(125)I]iodo-L-tyrosine ([(125)C]DCIT K(i), 1.5 nmol/L) were synthesized using [(11)C]CH(3)I and with [(125)I]NaI/Iodogen, respectively.RESULTS: At 30 minutes postinjection, [(11)C]DCMC and [(125)I]DCIT showed tumor/muscle ratios of 10.8 and 4.7, respectively, with clear delineation of LNCaP-derived tumors on imaging. MCF-7- and PC-3-derived tumors showed significantly less uptake of [(11)C]DCMC or [(125)I]DCIT. CONCLUSION: These results show the feasibility of imaging PSMA-positive prostate cancer using low molecular weight agents.  相似文献   
116.
目的:探讨针刺导气法治疗急性腰扭伤的临床价值.方法:将60例急性腰扭伤患者随机单盲分为两组,观察组30例,在针刺得气的基础上施以导气法治疗;对照组30例,在常规针刺得气后留针20 min.3 d后观察疗效.结果:观察组痊愈率为86.7%,对照组为43.3%,观察组痊愈率明显优于对照组(P<0.01).结论:针刺导气法是治疗腰扭伤的一种较好的方法.  相似文献   
117.
三叉神经痛是指三叉神经分布范围内反复出现的阵发性短暂剧烈疼痛。罹患此病,轻者影响正常生活,重者痛不欲生。患者自觉痛如刀割、锥刺、火灼、电击、常伴有同侧面部肌肉抽搐,一般无感觉缺失等神经传导功能障碍。并常见到有激发点(扳机点)的存在,即如在刷牙、洗脸、进食、言语等动作时,接触三叉神经分布区某一部皮肤或粘膜等,均可激发疼痛发作。  相似文献   
118.
目的:评价时间分辨荧光免疫技术与斑点金免疫层析技术在实际工作中的应用。方法:采用两种方法同时检测88份标本血清,并进行结果比对。结论:二者存在Kappa值高度一致,但DICA法灵敏度不高,有一定的误检率。因而仅适合于筛查、床边检验、和家庭检验。而TRFIA法则以其更灵敏、特异性更强、可定量分析的优点将在医院临床检验中得到更好的应用。  相似文献   
119.
120.
PURPOSE: Recent studies have highlighted that the p53 codon 72 polymorphism plays a crucial role in modulating wild-type p53 apoptotic capacity, and as such may influence the response to chemotherapy. Thus, the purpose of this study was to investigate whether the p53 codon 72 polymorphism might influence pathologic response to neoadjuvant chemotherapy in primary breast cancer. EXPERIMENTAL DESIGN: One hundred and ten operable breast cancer patients received anthracycline-based neoadjuvant chemotherapy and p53 codon 72 polymorphism status was analyzed by PCR-RFLP. RESULTS: The distribution of initial clinical stage, tumor size, estrogen receptor or progesterone receptor status, menopausal status, or erbB2 expression was not significantly different among the polymorphic variants. However, we found that only 13% (3 of 23) of patients with the Pro/Pro variant had a good pathologic response, defined as a complete pathologic response or minimal residual disease. In comparison, 40% (22 of 55) or 37.5% (12 of 32) of patients with the Pro/Arg or Arg/Arg variant had a good pathologic response (P = 0.019). Moreover, patients with the Pro/Pro variant were more likely to have a positive axillary lymph node status than those with the Pro/Arg or Arg/Arg variant (P = 0.007). Furthermore, in multivariate analysis, p53 codon 72 polymorphism was found to be a strong predictor of pathologic response (odds ratio 6.7, 95% confidence interval, 1.4-31.2; P = 0.016). CONCLUSION: Our study indicates that breast cancer patients with the Pro/Pro variant may be less sensitive to anthracycline-based treatment than those with the Pro/Arg or Arg/Arg variant and suggests that analysis of p53 codon 72 polymorphism may provide a simple predictive marker for selecting the right breast cancer patients to anthracycline-based neoadjuvant chemotherapy in clinical setting.  相似文献   
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