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71.
Although human complement‐dependent cytotoxicity (CDC) of α1,3‐galactosyltransferase gene‐knockout (GTKO) pig cells is significantly weaker than that of wild‐type (WT) cells, successful xenotransplantation will require pigs with multiple genetic modifications. Sera from healthy humans were tested by (i) flow cytometry for binding of IgM/IgG, and (ii) CDC assay against peripheral blood mononuclear cells and porcine aortic endothelial cells from five types of pig – WT, GTKO, GTKO transgenic for H‐transferase (GTKO/HT), WT transgenic for human complement regulatory protein CD46 (CD46) and GTKO/CD46. There was significantly higher mean IgM/IgG binding to WT and CD46 cells than to GTKO, GTKO/HT, and GTKO/CD46, but no difference between GTKO, GTKO/HT, and GTKO/CD46 cells. There was significantly higher mean CDC to WT than to GTKO, GTKO/HT, CD46, and GTKO/CD46 cells, but no difference between GTKO and GTKO/HT. Lysis of GTKO/CD46 cells was significantly lower than that of GTKO or CD46 cells. CD46 expression provided partial protection against serum from a baboon sensitized to a GTKO pig heart. GTKO/CD46 cells were significantly resistant to lysis by human serum and sensitized baboon serum. In conclusion, the greatest protection from CDC was obtained by the combination of an absence of Gal expression and the presence of CD46 expression, but the expression of HT appeared to offer no advantage over GTKO. Organs from GTKO/CD46 pigs are likely to be significantly less susceptible to CDC.  相似文献   
72.
异基因造血干细胞移植(hematopoieticcelltransplantation,HCT)后代谢综合征的发生主要由预处理导致的神经激素系统紊乱、血管内皮损伤、移植物的免疫和炎症作用以及继发的移植物抗宿主病及其治疗等引起。对代谢综合征及其组分(糖尿病、高血压、血脂紊乱等)的筛查可以尽早地调整治疗策略,控制危险因素的发生,进而降低远期的心血管疾病的发生率和致死率。为此,美国的研究人员回顾性分析了86例异基因HCT受者代谢综合征的发生情况,并与代谢综合征在普通人群中的流行情况进行比较。  相似文献   
73.
Objective To study the risk factors of infection of extended-spectrum beta-lactamases (ESBL) -producing strains and drug resistance of Enterobacteriaceae that infected burn patients. Methods A retrospective study was performed on clinical information of 92 patients with Enterobacteriaceae infection in our burn unit from January 2001 to December 2008. The distribution and drug resistance of Enterobacteriaceae , and the detection rate, drug resistance of ESBL-producing strains, and its risk factors of nosocomial infection were analyzed. Data were processed with Chi-square test. Results One hundred and nine strains of Enterobacteriaceae were isolated, with 38 (34.9%) strains of Enterobacter cloacae , 25 (22.9%) strains of Escherichia coli , 22 (20. 2%) strains of Klebsiella pneumoniae , 13 (11.9%) strains of Proteus mirabilis , and 11 (10. 1%) other strains of Enterobacteriaceae . Enterobacteriaceae were moderately or highly resistant to antibiotics except imipenem, resistance rate of which was less than 8. 0%. ESBL-producing strains accounted for 44. 0% in Escherichia coli , and 77. 3% in Klebsiella pneumoniae . Drug-resistance rate of ESBL-producing strains to antibiotics was obviously higher than that of non ESBL-producing strains. Length of hospital stay longer than 20 days, and use of the third-generation cephalosporin longer than 5 days, quinolone antibiotics longer than 7 days, and topical antibiotics longer than 5 days were the risk factors of nosocomial infection caused by ESBL-producing strains, comparing with non ESBL-producing strains, the difference was statistically significant (with χ2 value respectively 5.491 , 4.441, 15. 186, 4. 938 , P values all below 0. 05) . Conclusions Enterobacteriaceae strains in burn unit of our hospital are highly drug resistant, with high lactamase-producing rates, calling for intense monitor to control the risk factors that predispose the infection of ESBL-producing strains in order to lower the infection rate.  相似文献   
74.
目的 比较高风险患者腹主动脉瘤(abdominal aortic aneurysm,AAA)手术治疗(opensurgical repair,OSR)与腔内治疗(endovascular aneurysm repair,EVAR)的效果,探讨高风险患者AAA治疗方式的选择.方法 利用(customized probability index,CPI)危险评分方法[1]筛选出我院1998年至2008年高风险患者55例,比较OSR组(20例)与EVAR组(35例)围手术期及术后近期结果.结果 OSR组随访率100%,平均随访6年3个月.EVAR组随访率94%,平均随访5年10个月.(1)手术时间高风险患者EVAR组(3.1±0.6)h短于OSR组[(4.9±0.9)h(P<0.05)];(2)EVAR组术中出血、ICU时间和住院时间均短于OSR组(P<0.01);(3)围手术期死亡率EVAR组(2.86%)明显低于OSR组(15.00%);(4)术后并发症发生率EVAR组(17%)明显低于OSR组(40%);(5)EVAR组术后并发症主要为内漏(8.57%);(6)OSR组并发症主要为心脏相关性疾病(25%).结论 EVAR对于高风险患者AAA的治疗可以更少的导致围手术期心血管事件的发生,降低围手术期的死亡率和并发症发生率.CPI可以相对准确评估血管手术围手术期死亡率和并发症的发生率,可用于指导围手术期的治疗策略.  相似文献   
75.
76.
近肾动脉腹主动脉下段闭塞症的手术方法探讨   总被引:2,自引:0,他引:2  
目的探讨近肾动脉腹主动脉下段闭塞症(juxtarenal aortic occlusion)的手术治疗方法。方法总结自1995年以来作者收治的27例腹主动脉末端闭塞症的临床治疗,术中暂时阻断肾上主动脉(平均7min),纵行切开主动脉,迅速清理近肾主动脉病灶,缝合上段纵行切口后改为肾动脉下主动脉阻断,完成人工血管主-股动脉转流手术。结果术后22例触及股动脉和胭动脉搏动,术后7d患肢缺血症状均得以改善。手术后3月复查,患肢缺血症状消失,25例阳痿现象得到改善,彩色超声显示血管吻合口及人工血管内均未见血栓。25例获得1年以上的随访,吻合口通畅率为100%;18例获得5年以上随访,吻合口通畅率为94.4%。结论将肾上主动脉暂时阻断后纵行切开主动脉,迅速去除病灶,主动脉缝合成型,然后在肾下主动脉阻断后完成主-股动脉转流是治疗腹主动脉末端闭塞性疾病较好的手术方案。  相似文献   
77.
目的探讨胆道镜下液电碎石术联合B超治疗胆道术后残留结石临床价值和疗效。方法将82例术后肝内胆管残留结石患者分为两组,胆道镜辅以术中B超经T管窦道液电碎石取石治疗肝内胆管术后残石42例为治疗组。以胆道镜取石40例患者为对照组。结果治疗组结石取净率显著高于对照组(P〈0.05),平均手术时间、手术次数、住院时间和平均住院费用等明显优于对照组(P均〈0.05)。两组患者手术后均无严重并发症。结论胆道镜下液电碎石术联合术中B超治疗术后肝内胆管残留结石,具有定位准确、创伤小、安全有效、可重复操作等优点,值得临床推广使用。  相似文献   
78.
Although laparoscopic cholecystectomy (LC) has become the gold standard for the management of gallstone disease, the application of laparoscopic common bile duct exploration (LCBDE) for choledocholithiasis has been slower. The aim of this study is to determine the feasibility and effectiveness of LCBDE. A retrospective cohort study was conducted to compare LCBDE (n = 82) with conventional common bile duct exploration (CCBDE) (n = 75) and endoscopic sphincterotomy (EST) (n = 80) in the management of choledocholithiasis. All our LCBDEs were performed through choledochotomy with T-tube placement. The mean operative time of the LCBDE group (124 +/- 48 minutes) was not significantly longer then the CCBDE group (118 +/- 35 minutes), while the postoperative hospitalization was shorter in both the LCBDE (8 +/- 5 days) and EST (9 +/- 4 days) groups than in the CCBDE (13 +/- 6 days) group. In the LCBDE group, 14 patients (17.1%) required postoperative choledochoscopy to clear residual stones through the T-tube tract. The only mortality occurred in the CCBDE group. The morbidity rate was 3.7% (3/82) in the LCBDE group, including bile leakage in 1 case and bile peritonitis in 2 cases; 6.7% (5/75) in the CCBDE group, including atlectasis in 2 cases, sepsis in 1, and wound infection in 2. There were 2 cases of postoperative pancreatitis (2.5%; 2/80) in the EST group. The difference in the average number of sessions needed for complete clearance of choledocholithiasis in each group was statistically significant (EST, 1.46 +/- 0.67; LCBDE, 1.23 +/- 0.42; and CCBDE, 1.09 +/- 0.28; P < 0.0001). Our results suggested that EST and LCBDE tended to require more therapeutic sessions then CCBDE, although these sessions were less invasive. The benefits of LCBDE include minimal invasiveness, concurrent treatment of gallbladder stone and CBD stones in a single session, and a shorter postoperative hospital stay. However a longer learning curve is needed. Selection of the most suitable therapeutic option for individual patients by an experienced surgeon gives the most benefits to patients.  相似文献   
79.
渤海鱼类和头足类异尖科线虫幼虫感染情况调查   总被引:5,自引:0,他引:5  
[目的 ]调查渤海鱼类和头足类异尖科线虫幼虫感染情况 .[方法 ]对渤海 2 5种鱼 2 90尾和 3种头足类 10 8尾进行剖检 .[结果 ]发现 19种鱼 15 6尾和 1种头足类 8尾感染异尖科线虫幼虫 6种 ,计73 2 7条 .从 15种鱼 (N =191)中的 12 1尾 ( 63 4 % )和一种头足类 (N =5 4 )中的 8尾 ( 14 8% )体内检出简单异尖线虫幼虫 5 992条 ,占总数的 81 8% ,4种鱼是本幼虫的新发现宿主 .其余 13 3 5条幼虫中 ,15 4( 2 1% )条为鲔蛔线虫B型幼虫 ,采自 4种鱼 2 3尾 ;10 13 ( 13 8% )条为鲔蛔线虫C型幼虫 ,采自 13种鱼79尾 ;164( 2 2 % )条为宫脂线虫中国V型幼虫 ,采自 4种 2 0尾鱼 ;2种鱼感染针蛔虫幼虫 3条 ;仅发现 1条伪新地蛔虫幼虫 .  相似文献   
80.
DNA amplification by Polymerase Chain Reaction (PCR) of a repetitive sequence specific for Mycobacterium tuberculosis, from clinical samples of extra pulmonary origin were evaluated. The 123 base pair fragment of the insertion element IS 6110 in Mycobacterium tuberculosis was amplified. A total of 50 samples were analysed by PCR and compared with culture on Lowenstein-Jensen medium (LJ) and the clinical findings of the patient. Out of the total 26 samples were positive by PCR, while only seven grew the bacilli in culture. 24 samples were negative by PCR and culture. All the seven samples that grew the bacilli on culture were positive by PCR. In remaining 19 cases that were positive by PCR but did not grow the bacilli clinical features, radiological findings and Mantoux test were strongly suggestive of M. tuberculosis. All the amplification negative cases had no positive evidence of tuberculosis but were being followed up. When correlated with culture and clinical history the sensitivity of PCR for the diagnosis of active tuberculosis was 100%. However, the specifity was only 55.8% as culture on LJ (Gold Standard) was positive in only 7 samples out of 26 samples that were positive by PCR.KEY WORDS: DNA Amplification, IS 6110, Mycobacterium tuberculosis.  相似文献   
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