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In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.  相似文献   
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Molecular genetic characterization of XRCC4 function   总被引:2,自引:0,他引:2  
XRCC4 is a generally expressed protein of 334 amino acids that is involved in the repair of DNA double-strand breaks and in V(D)J recombination, but its function is unknown. In this study, we have used a mutational approach and the yeast two-hybrid method to perform an initial characterization of this protein. We show that the XRCC4 protein is located in the nucleus. We also demonstrate that several potential phosphorylation sites are not required for XRCC4 function in a transient V(D)J recombination assay. In addition, we show that XRCC4 forms a homodimer in vivo with the homodimerization domain being located within amino acids 115-204. Finally, we define a core domain of XRCC4 that functions in V(D)J recombination and comprises amino acids 18-204. Potential functions of XRCC4 are discussed.   相似文献   
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恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
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目的:目前临床进行隧道法舌根射频治疗时,其作用参数的设置仍缺乏统一的标准,故通过计算机三维重建射频损伤区域,分析猪舌根射频损伤体积与射频能量、时间的关系,从中得出应用舌根隧道法射频治疗的最佳作用能级和作用时间。 方法:实验于2006-06/2007-05在上海交通大学耳鼻喉科研究所完成。将36只实验用猪以射频作用能级1,2,3,4,5,6随机分成6组,每组6头猪,各个猪舌的作用时间分别设置为2,5,10,15,20,25s。用Coblation射频发生仪及Reflex55刀头进行猪舌根射频操作。射频作用后的舌根组织行连续冰冻切片,苏木精-伊红染色后,进行序列组织切片的全貌二维图像采集,对拟重建的结构进行边界提取和图像分割。将提取分割图像导入Image-Pro Solution图像处理软件,利用3D Constructor插件进行三维重建,并根据设定参数进行体积计算。用SPSS10.0统计学软件对所测数据进行统计学分析。 结果:①作用能级固定时,舌根组织射频损伤体积随时间延长而增大,符合Logarithmic回归曲线。②作用时间固定时,舌根组织射频损伤体积随能级增大而增大,符合直线回归。③射频损伤体积随能量增大而增加亦符合Logarithmic回归曲线。④Coblation射频治疗系统在能级6时,在作用10s之前,损伤体积随作用时间增加而迅速增加,其后变化趋势平缓,超过20s后损伤体积无显著增加。 结论:①舌根区域射频治疗时,舌根组织射频损伤体积与时间或能量呈Logarithmic曲线相关,与能级呈直线相关。②Coblation射频治疗系统在能级6时,最佳作用时间范围为10-20s。  相似文献   
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BACKGROUND: Assays that detect human T-lymphotropic virus type I and type II antibody (HTLV-I/II) are widely used in the routine screening of blood donors. STUDY DESIGN AND METHODS: Four commercially available anti-HTLV-I (Fujirebio and Organon Teknika) or -HTLV-I/II assays (Murex and Ortho) were evaluated in various serum panels: A) HTLV-I-positive specimens (n = 41), confirmed by Western blot and polymerase chain reaction; B) a commercially available anti-HTLV-I/II panel; C) serial dilutions of sera from HTLV-I-positive individuals (n = 30), confirmed by immunofluorescence assay and Western blot: D) serial dilutions of HTLV-II-positive blood donors (n = 20), confirmed by Western blot and polymerase chain reaction, and E) sera from first-time blood donors (n = 1055). RESULTS: All four assays elicited reactions in all 82 HTLV-I- positive samples in Panels A, B, and C. Of 32 HTLV-II-positive specimens in Panels B and D, 31 (96.9%) reacted in the Organon Teknika assay and all 32 reacted in the remaining tests. Probit analysis of test results in Panels C and D indicated that the Fujirebio test was the most sensitive assay, followed by Organon Teknika, Ortho, and Murex. The specificities of Fujirebio, Murex, Organon Teknika, and Ortho tests in 1055 first-time blood donors were 99.9, 100, 99.6, and 99.9 percent, respectively. CONCLUSION: All four studied assays for detecting HTLV-I or HTLV-I/II antibodies are appropriate as screening tests.  相似文献   
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目的:观察针刺足三里、悬钟2穴对缺血性脑卒中脑血管功能的影响,分析其可能的作用机制,并对临床疗效做出评价。方法:选择2004-11/2006-05湖北中医药高等专科学校附属古城医院针灸科、荆州市第五人民医院中医康复科、荆州市第三人民医院中医科3单位缺血性脑卒中患者合适病例160例,采用查随机数字表的方法,将其随机分为对照组和针刺组,各80例。对照组采用现代医学常规干预方法进行治疗:卧床,保持呼吸道通畅,预防感染,控制颅内压、血压,维持水电解质平衡。针刺组在此基础上加针刺足三里、悬钟2穴,采用慢速捻转进针法针刺,留针20~30min,每隔5min行针1次。1次/d。两组患者治疗30d。并以经颅多普勒检测观察缺血性脑卒中患者治疗前后脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能的变化,同时以治疗前后神经功能缺损程度为指标评价其临床疗效。结果:160例病例全部进入结果分析。①针刺组与治疗前相比,脑血管舒缩反应能力明显加强,差异有显著性意义(t=2.97,P<0.05),且优于对照组(t=2.45,P<0.05)。②针刺组与治疗前相比,脑血流自动调节能力明显改善,差异有非常显著性意义(t=8.01,P<0.01),且优于对照组(t=7.67,P<0.05)。③针刺组与治疗前相比,大脑半球侧枝循环代偿功能得到加强,差异有显著性意义(t=3.15,P<0.05),且优于对照组(t=5.16,P<0.05)。④针刺组与治疗前相比,神经功能缺损积分明显降低,差异有非常显著性意义(t=4.83,P<0.01),且优于对照组(t=5.43,P<0.05)。结论:针刺足三里、悬钟2穴对缺血性脑卒中患者脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能有明显改善作用,并能促进神经功能的恢复。  相似文献   
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Hepatitis C: a review and update   总被引:1,自引:0,他引:1  
The hepatitis C virus is an RNA virus that is a major cause of acute and chronic hepatitis. It is contracted chiefly through parenteral exposure to infected material such as blood transfusions or injections with dirty needles. Those at highest risk for development of hepatitis C are injection-drug users, people who snort cocaine with shared straws, and health care workers who are at risk for needle-stick and other exposures. Although the incidence of acute hepatitis C infection has fallen dramatically in the United States during the past decade, the prevalence of infection remains high (approximately 2.7 million Americans) because chronic hepatitis C develops in about 75% of those infected. Both acute and chronic hepatitis C are asymptomatic in most patients. However, chronic hepatitis C is a slowly progressive disease and results in severe morbidity in 20% to 30% of infected persons. Chronic hepatitis C is associated with a host of extrahepatic manifestations, many of which may be seen by dermatologists. The most frequent of these are mixed cryoglobulinemia with leukocytoclastic vasculitis and porphyria cutanea tarda. (J Am Acad Dermatol 2001;44:159-79.) Learning objective: At the conclusion of this learning activity, participants should be familiar with the essentials of the virology of the hepatitis C virus and the major features of the human diseases caused by hepatitis C viral infection; the extrahepatic manifestations of hepatitis C viral infection, with particular emphasis upon dermatologic manifestations, including leukocytoclastic vasculitis, porphyria cutanea tarda, and lichen planus; and the current methods of management of hepatitis C and its extrahepatic manifestations.  相似文献   
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