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21.
舒胆合剂防治阻塞性黄疸肾功能障碍的作用机制   总被引:2,自引:0,他引:2  
目的 探讨在阻塞性黄疸(OJ)时舒胆合剂的抗内毒素及对肾功能的保护作用。方法 SD大鼠胆总管结扎后分3组,每组10只,分别用2mL舒胆合剂、乳果糖液(每100mL含乳果糖67g)、生理盐水灌胃,连用9d。假手术组10只,用2mL生理盐水灌胃。观察内毒素、血和肾组织中内皮素(ET)、一氧化氮(NO)的含量、一氧化氮合酶(NOS)活性及肾功能的变化。结果 舒胆合剂组与乳果糖组血内毒素、血和肾组织ET水平较生理盐水组明显降低,血和肾组织N0、NOS活性、内生肌酐清除率、肾皮质血流量较生理盐水组明显升高。结论 在OJ时,中药舒胆合剂有抗内毒素作用,并通过减少体内内毒素水平来降低体内ET水平,升高N0水平起到保护肾功能的作用。  相似文献   
22.
Objective: To make an epidemiological analysis of the effect of environment on extremely severe road traffic crashes (RTCs). Methods: Epidemiologic data of extremely severe RTCs associated with environmental factors, including weather, topography, road conditions and other traffic conditions in Mainland China during 2000-2001, were collected and analyzed. Results: ( 1 ) During 2000-2001, there were 3 365 extremely severe RTCs with 13 666 deaths, 12 204 injuries and a direct economical loss of 136 million RMB. ( 2 ) Most extremely severe RTCs occurred in fine weather days and in the daytime. The high occurrence sites were plain areas, horizontal and straight roads, Grade B and C roads, ordinary road segment, and asphalt, smooth and mixed roads. (3) Compared with other RTCs, extremely severe RTCs were more likely to happen under following conditions: on cloudy, snowing, misty and blustering days; in hill and mountainous areas; on crooked and sloping roads; on freeway, Grade A, B, and C roads; mixed roads; ordinary, bridge, narrow and transitional roads; sand and dirt-roads; without traffic control measures; night without lighting. (4) Extremely severe RTCs of mountainous area or crooked and sloping roads were most severe in terms of deaths and injures per crash. Conclusions: Extremely severe RTCs are closely related with environmental factors. Rational road programming, enhancing road establishment and improving road conditions are probably effective measures to reduce the road traffic injuries.  相似文献   
23.
本文报道尿道损伤46例,占同期泌尿系损伤的70%。分析尿道损伤手术术式和疗效,以尿道对端吻合最好.尿道会师牵引术亦有其优点。  相似文献   
24.
A cohort of 5180 patients with head and neck cancer, who were part of the tumor registry of the Surveillance, Epidemiology, and End Results area of western Washington State, was followed up for as many as 15 years to determine the risk of lung cancer. A sample of 522 patients from this cohort was interviewed to determine smoking history. Lung cancer developed in 356 (6.9%) of the 5180 patients. The overall annual incidence of lung cancer remained relatively constant between approximately 1.0% and 2.0% during the 15 years of follow-up. Men had an increased risk of lung cancer compared with women (relative risk [RR] = 1.56; 95% confidence interval [CI] = 1.18 to 2.03). Compared with patients with oral cavity cancer (RR = 1.00), the relative risk of lung cancer developing by the site of the index tumor was 0.63 (95% CI = 0.40 to 0.98) for lip, 1.12 (95% CI = 0.81 to 1.56) for intrinsic larynx, 1.73 (95% CI = 1.21 to 2.47) for oropharynx, 1.84 (95% CI = 1.16 to 2.92) for hypopharynx, and 2.28 (95% CI = 1.60 to 3.24) for extrinsic larynx. Among the 522 patients who were interviewed, men smoked more than women ( p < 0.0001), and patients with laryngeal or pharyngeal cancer smoked more than patients with cancer of the lip or the oral cavity ( p < 0.05). Among patients with head and neck cancer, the risk of lung cancer is highest for men and for patients with cancer of the pharynx or extrinsic larynx. These findings may be explained by differences in smoking consumption. (Otolaryngol Head Neck Surg 1997;116:630-6.)  相似文献   
25.
Purpose: The multifunctional cytokine, transforming growth factor β1 (TGF-β), plays an important role in the development of injury-associated intimal hyperplasia (IH). Strategies to suppress local TGF-β activity may have a clinical potential to prevent restenosis caused by IH. Photodynamic therapy (PDT) involves the local generation of cytotoxic free radicals by light activation of photosensitizer dyes and has been shown to inhibit experimental IH. This study investigated whether PDT-generated free radicals can affect TGF-β activity in a biologic system using vascular smooth muscle cells (SMCs).Methods: The release and activation of TGF-β by injured SMCs in culture was compared between mechanical injury and PDT. Mechanical injury was induced with a rubber policeman, and PDT was performed with the photosensitizer chloroaluminum sulfonated phthalocyanine (5 μg/ml) and 675 nm laser light at subtherapeutic 10 J/cm2 and the in vivo therapeutic dose of 100 J/cm2. Cell viability was assessed by the tetrazolium salt conversion assay, and active and total (active + latent) TGF-β was determined by enzyme-linked immunosorbent assay in the conditioned media of SMCs 24 hours after treatment. Functional TGF-β activity was assessed by inhibition of endothelial cell mitogenesis.Results: Both forms of injury severely reduced (p < 0.0005) SMC viability to less than 15%. In untreated SMC conditioned media, only 14.5% of the total TGF-β was active (27.7 ± 8.7 pg per 1 × 105 cells). However, after mechanical injury and PDT with 10 J/cm2, there was a significant increase (p < 0.02) in active TGF-β (60.1 ± 10.1 pg and 48.6 ± 21.0 pg, respectively), despite a total reduction of approximately 50%. In contrast to this result, PDT with 100 J/cm2 did not result in increased levels of active TGF-β (8.1 ± 3.5 pg), despite having similar levels of total TGF-β. Consequently, the conditioned media of SMCs that had 100 J/cm2 PDT did not inhibit endothelial cell mitogenesis as compared with the conditioned media of SMCs with mechanical injury and 10 J/cm2 PDT (p < 0.0002).Conclusions: This report describes two novel findings: (1) injury to SMCs in vitro induces the conversion of biologically latent TGF-β to active TGF-β; and (2) the therapeutic PDT dose interferes with this injury activation process. This study substantiates the concept of local cytokine inhibition by PDT in a biologic system and provides new insights into the mechanisms of PDT-mediated inhibition of experimental IH. (J Vasc Surg 1997;25:1033-43.)  相似文献   
26.
杨光  蔡振杰  王晓武  郑奇军  胡军 《医学争鸣》2002,23(20):1905-1907
目的 总结原位心脏移植术后急性排异反应的监测。方法 2000-01/2002-04施行11例原位心脏移植手术,结合临床表现、心电图、超声心动图、化验检查及心内膜活栓等检查,对心脏移植术后急性排异反应的监测进行分析。结果 采用临床症状+心电图+超声心电图+心肌血清学检测综合判断有6次急性排异反应,行心内膜活检证实Ⅰb级2次,Ⅲa级3次;术后常规行心内膜活检21次,仅发现急性排异反应Ⅰa或Ⅰb级5次。结论 急性排异反应是关系到心脏移植术后患者康复及愈后的重要因素,因此要及时、有效地进行监测;心内膜心肌活检是诊断急性排异反应敏感可靠的方法,但为有创性检查,有一定的并发症风险,其他多项无创性检查可作辅助指标,因此急性排异反应监测应把无创性检查与心内膜心肌活检有机地结合起来。  相似文献   
27.
28.
目的 观察逆转录病毒转病毒白细胞介素 10 (vIL 10 )基因在体内的表达。方法 用MSCVneo vIL 10重组体在体外转导CBA (H 2 K)小鼠的造血干细胞 (HSCs) ,给经致死照射(90 0rads)的 2 0只同基因CBA(H 2 K)小鼠注入经MSCVneo vIL 10转染的HSCs ,2× 10 6HSCs/只。酶联免疫吸附测定 (ELISA)、逆转录 聚合酶链反应 (RT PCR )、Westernblot分析vIL 10的表达。结果 移植MSCVneo vIL 10转染HSCs的 2 0只小鼠 ,移植后 8周用ELISA检测 ,其中 15只小鼠血清的vIL 10浓度为 :2 70~ 13 40ng/L ,5只小鼠血清的vIL 10为阴性。 12周后有 2只小鼠vIL 10测不出 ,13只小鼠长时间表达vIL 10达 6个月。对照组小鼠血清vIL 10均为阴性。RT PCR和Westernblot证实小鼠的器官均有vIL 10的mRNA和蛋白的表达。结论 逆转录病毒能有效地将vIL 10基因导入造血干细胞并在体内长时间表达。  相似文献   
29.
应用不经胸食管钝性剥离拔脱术治疗26例咽下癌与高位食管癌,效果良好,术后5例发生开发症,其中颈部吻合口痿3例,暂时性咳呛1例,腹部切口局限裂开1例。手术死亡率7.6%(2/26)。介绍了手术方法,对不经胸施术、胃体缝缩、颈部食管胃Gambee氏吻合法应用进行了讨论。  相似文献   
30.
老年疝环充填式无张力疝修补术的应用   总被引:1,自引:0,他引:1  
目的:探讨老年人疝环充填式无张力疝修补术的近期疗效。方法:对35例次老年人疝环充填式无张力疝修补术的临床资料进行回顾性分析。结果:平均手术时间40min,住院天数3-7d。术后8-30h均能下床活动。全部未使用镇痛药物。并发症:急性尿潴留1例,恶心呕吐1例,术后低热2例。切口感染率及近期复发率均为0。结论:疝环充填式无张力疝修补术具有操作简便、创伤小、恢复快、无张力、低复发率、适应症宽的优点而成为老年腹股沟疝的理想术式。  相似文献   
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