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161.
Mycophenolate mofetil (MMF) used in a triple-drug regimen has been shown to decrease acute rejection rates, compared to a double-drug regimen. The impact of MMF on late acute rejection (LAR) episodes has not been well described. To investigate the risk of LAR (rejection > or = 6 months post-transplantation) data from the Scientific Registry of Transplant Recipients (SRTR) were used. We studied adult primary liver transplant recipients transplanted between June 1, 1995, and April 30, 2004, with hepatitis C virus (HCV) (n = 3356), hepatitis B virus (HBV) (n = 550) or a nonviral (n = 5740) primary cause of liver disease who were recorded as receiving continuous 3-(MMF + Tacro + steroids) versus 2-drug (Tacro + steroids) therapy for at least 6 months immediately post transplantation. Kaplan-Meier analysis showed significantly lower LAR rates 4 years post-transplant in 3- versus 2-drug HCV, HBV and nonviral disease patients. Multivariate regression confirmed 3- versus 2-drug therapy to be associated with a decreased risk of LAR. Late graft survival was significantly lower at 4 years post-transplant for patients with LAR 6-12 months post-transplantation versus patients with early rejection (78.0% vs. 87.0%, p < 0.001) and no rejection (88.1%, p < 0.001). Three-drug versus 2-drug therapy for a minimum of 6 months may offer a better treatment strategy to avoid the consequences and expense of LAR episodes.  相似文献   
162.
AIMS: To examine the effects of agents that alter potassium adenosine triphosphate (KATP) channel activity in beta-cells on cognitive function and counterregulatory hormone responses during acute hypoglycaemia, given the physiological similarities between the pancreatic beta-cell and the hypothalamic glucose-sensitive neurones (GSN) and the widespread distribution of sulphonylurea receptors in neuronal cells throughout the brain. METHODS: Ten healthy males were studied on four occasions and in random order underwent three stepped hypoglycaemic (plasma glucose aims: 3.4, 2.8, 2.4 mmol/l) and one euglycaemic (plasma glucose aim: 5 mmol/l) insulin clamps. Prior to each hypoglycaemic study, volunteers received either 10 mg glibenclamide, or 5 mg/kg diazoxide or placebo orally. Cognitive function, symptom scores and counterregulatory hormone responses were measured at each glycaemic level. RESULTS: There was no statistically significant effect of either drug on the symptoms generated or the counterregulatory hormonal response during hypoglycaemia. However, cognitive function was better preserved during hypoglycaemia in the glibenclamide-treated arm, particularly four-choice reaction time which deteriorated at a plasma glucose 2.5 mmol/l compared with 3.0 mmol/l with diazoxide (P = 0.015) and 2.9 mmol/l with placebo (P = 0.114). CONCLUSIONS: Single doses of pharmacological agents which alter membrane KATP channel activity do not affect the counterregulatory response to hypoglycaemia but may modify cognitive function during cerebral glucopenia. The unexpected effects of glibenclamide on cortical function suggest a novel action of sulphonylureas that warrants further investigation.  相似文献   
163.
妊娠性肝内胆汁淤积症(ICP)的主要特征是:母体难以忍受的瘙痒症,血清胆汁酸升高(≥10μmol/L)以及胎儿死亡风险的增加。最近,确定了一个与影响胎儿损害相关的界值,即血清胆汁酸≥40μmol/L。在一项双盲、安慰剂对照试验中,作研究了熊脱氧胆酸(UDCA)和地塞米松对瘙痒症、胆汁淤积的生化指标和胎儿并发症发生率的影响。为此,选取了130例患有ICP的妇女,随机分到UDCA组(1g/d,使用3周),地塞米松组(12mg/d使用1周,第2周、第3周使用安慰剂)和安慰剂组(使用3周)进行治疗。在治疗期间和治疗3周后对瘙痒症和胆汁淤积的生化指标进行分析。在分娩时记录胎儿的并发症(自发性早产,新生儿窒息,羊水、胎盘、胎膜的胎粪染色)。意向治疗分析显示仅在UDCA组中,丙氨酸转氨酶(ALT)(P=0.01)和胆红素(P=0.002)明显减少。在血清胆汁酸≥40μmol/L的ICP妇女的亚群分析中发现(n=34)UDCA对瘙痒症(减轻75%)、胆汁酸(下降79%)、ALT(降低80%)和胆红素(降低50%)也有明显效果,但对胎儿并发症发生率无影响。地塞米松并无减轻瘙痒症或降低ALT的作用,在降低胆汁酸和胆红素方面比UDCA效果差。  相似文献   
164.
目的:SCANDSTENT试验旨在评价西罗莫司洗脱支架(SES)在复杂冠状动脉病变中的应用。背景:与裸金属支架(BMS)相比,在简单冠状动脉病变中使用SES能够改善造影和临.床的结果,但是,有关在复杂病变中使用SES的安全性和有效性的证据有限。方法:322例有症状的复杂冠状动脉疾病患者被随机分配接受SES或BMS治疗。病变形态分别为全闭(36%)、分叉(34%)、开口(22%)或成角(8%)改变。主要终点为支架置入6个月后血管最小管腔直径的差别。  相似文献   
165.
To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions.  相似文献   
166.
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males.  相似文献   
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169.
The finer branches of the biliary tree (FBBT) contain a regenerative compartment. We hypothesized that preservation of the FBBT together with its microvasculature will lead to recovery of biliary damage and prolonged preservation of bile ductules during the development of chronic liver allograft rejection. The interlobular bile ducts, portal bile ductules and extraportal biliary cells with and without microvessels were studied in sequential biopsies in five patients who fulfilled the Banff criteria of early chronic rejection (CR) (imminence group). Biopsies of CR patients (n = 12) served as controls. Biopsies were double immunostained with CD34 (microvessels) and cytokeratin 7 (biliary structures). Proliferation and proangiogenic activity were assessed with Ki67 and VEGF-A immunostaining. Severe damage of bile ducts in the imminence group did not progress to significant bile duct loss. This was associated with a high proliferative activity in all biliary structures and preservation of the microvascular compartment. VEGF-A expression was increased in all but the reperfusion biopsies. In conclusion, both regenerative activity of the FBBT and an intact microvascular compartment are associated with less damage of the biliary tree and could therefore be prerequisites for biliary regeneration.  相似文献   
170.
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