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医源性胆管狭窄X线表现   总被引:1,自引:0,他引:1  
本文报道了13例医源性胆管狭窄,分析其影像表现。特点为:环形狭窄;线样狭窄,包括规则的和不规则的线样狭窄;闭塞性狭窄;胆管闭塞和胆管中断分离。ERCT和PCT对狭窄的形态,位置及长度显示优于CT和US。  相似文献   
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BackgroundHuman studies on exercise, cognition, and apolipoprotein E (APOE) genotype show that ε4 carriers may benefit from regular physical activity.MethodsWe examined voluntary wheel-running, memory, and hippocampal plasticity in APOE ε3 and APOE ε4 transgenic mice at 10–12 months of age.ResultsSedentary ε4 mice exhibited deficits in cognition on the radial-arm water maze (RAWM), a task dependent on the hippocampus. Six weeks of wheel-running in ε4 mice resulted in improvements on the RAWM to the level of ε3 mice. Hippocampal brain-derived neurotrophic factor (BDNF) levels were similar in ε3 and ε4 mice, and after exercise BDNF was similarly increased in both ε3 and ε4 mice. In sedentary ε4 mice, tyrosine kinase B (Trk B) receptors were reduced by 50%. Exercise restored Trk B in ε4 mice to the level of ε3 mice, and in ε4 mice, exercise dramatically increased synaptophysin, a marker of synaptic function.ConclusionsOur results support the hypothesis that exercise can improve cognitive function, particularly in ε4 carriers.  相似文献   
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The first universal hepatitis B vaccination program for newborns in the world was launched in Taiwan in July 1984. Most studies on the effectiveness of hepatitis B vaccination focused on the seroprevalence of HBs Ag among children under 14 years old. Only few studies focused on the seropositivity of anti-HBs among adolescents aged 15–18 years old. The present study aimed to evaluate the impact of the nationwide hepatitis B vaccination program on the immunity to HBV infection and the necessity of boost among adolescents. In this study including eight annual seroprevalence surveys from 2000 to 2007, 2342 college entrants (1589 15-year-olds in group I and 753 18-year-olds in group II) and 1851 university freshmen (18-year-olds in group III) participated. Subjects identified anti-HBs, HBs Ag and anti-HBc negative were given boost three doses of HBV vaccine. The HBs Ag seroprevalence was 11.6%, 3.5% and 1.0% for participants who were born before 1984, 1984–1986 and after 1986. The anti-HBs-seropositive rates were significantly higher in group II (83.1%) than in group I (53.0%) and group III (53.5%). All 572 participants who were seronegative for anti-HBs, HBs Ag and anti-HBc became anti-HBs-seropositive after catch-up vaccination. It is concluded that the anti-HBs-seropositive rate decreased to 50% in 15 years after vaccination, and boost vaccination was 100% effective. The necessity and age for boost among anti-HBs negative adolescents and the timing of the first immunization should be further evaluated.  相似文献   
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An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively.  相似文献   
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BACKGROUND: Oral submucous fibrosis (OSF) is a chewing habit-related pre-cancerous condition of the oral mucosa affecting predominantly south Asians. It is histopathologically characterized by epithelial atrophy and fibrosis of the subepithelial connective tissue. Fibrosis extends all the way into the muscle layer, leading to difficulty in mouth opening. However, the dynamics of extracellular matrix (ECM) remodeling with OSF progression is largely unknown. METHODS: Forty biopsy specimens of OSF and 10 of normal buccal mucosa were examined for expression/deposition modes of eight ECM molecules by histochemistry, immunohistochemistry, and in situ hybridization. RESULTS: In the early stage of OSF, tenascin, perlecan, fibronectin, collagen type III were characteristically enhanced in the lamina propria and the submucosal layer. In the intermediate stage, the ECM molecules mentioned above and elastin were extensively and irregularly deposited around muscle fibers. In the advanced stage, such ECM depositions decreased and were entirely replaced with collagen type I only. Their gene expression levels varied with progression of fibrosis, but the mRNA signals were confirmed in fibroblasts in the submucosal fibrotic areas. CONCLUSIONS: The results indicate that the ECM remodeling steps in OSF are similar to each phase of usual granulation tissue formation. Restricted mouth opening may be a result of loss of variety of ECM molecules including elastin into the homogeneity of collagen type I replacing muscle fibers.  相似文献   
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