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Purpose To determine the efficacy of a cystoscopic approach, as definitive treatment of ureteral fistulae, after failure of antegrade ureteral stent insertion.Methods Of 43 ureter fistulae encountered over 4 years, 10 postoperative and/or postradiotherapy fistulae could not be stented via an antegrade approach alone. A cystoscopic approach was used, with the antegrade approach available as back-up, if necessary.Results In two patients the ureteral orifice could not be visualized cystoscopically, thus precluding the retrograde approach. In the eight remaining patients, the retrograde approach alone never allowed successful stenting. In six patients, combined antegrade and retrograde approaches permitted stent insertions. In three of those six patients, a complex catheterization procedure was necessary. In two patients the combined approach failed altogether. Therefore, 6 of 10 patients underwent a successful stenting procedure with the combined approach; all ultimately closed the fistula.Conclusion Antegrade stent insertion remains the treatment of choice for ureteral leaks. If the antegrade approach fails, the retrograde approach alone is not likely to be successful. Instead, a combination of both approaches often does succeed.  相似文献   
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Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
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Molecular epidemiology of hepatitis B virus infections in Denmark.   总被引:3,自引:0,他引:3  
BACKGROUND: Denmark has a low incidence of acute hepatitis B (HBV) infections but the impact of an increasing number of immigrants with chronic HBV infection on HBV transmission is unknown. OBJECTIVES: To characterise individuals with chronic and acute HBV infection in a defined region and to examine the importance of different risk groups for the current HBV transmission. METHODS: During 2000-2001 all consecutive HBV infected individuals routinely diagnosed through the regional HBV serology laboratory in the County of Funen were classified according to ethnicity, presumed route of transmission and stage of infection based on clinical data mainly supplied by the requesting physician. HBV DNA was sequenced and subjected to phylogenetic analysis. RESULTS: Of 309 identified cases, 91 (29%) were classified as acute infection. HBV DNA sequencing was possible in 54 (59%) of these cases. Phylogenetic analysis showed that HBV isolated from injecting drug users (IDUs) was identical or closely related. Among acute cases acquired in Denmark 89% (74/83) were seen in IDUs (65) or in individuals presumably exposed to IDUs (nine) and phylogenetic analysis corroborated the assumption of IDU related transmission in every case with available sequence data. Among 83 ethnic Danes who acquired their HBV infection in Denmark, no new cases of transmission from immigrants were detected. CONCLUSION: Injecting drug use was the single most important factor for hepatitis B transmission in Denmark. The current Danish vaccination strategy is unable to protect IDUs from HBV infection and IDUs pose a greater risk of HBV transmission to the general population than immigrants.  相似文献   
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A further modification of the standard RPHA technique (Hepatest, Wellcome Reagents) for the detection of HBsAg is described. This modification does not require a centrifugation step which is required by the other modifications that have been described previously and consequently takes a little longer to perform. It does, however, retain the advantages of increased sensitivity and decreased costs which are also features of the other modifications. A series of 939 routine clinical specimens were used to evaluate the method described and to evaluate a new RIA kit for the detection of HBsAg (Hepatube, Wellcome Reagents). Of 53 specimens found to be positive for HBsAg by RIA, 50 (94% were detected by the modified Hepatest RPHA as opposed to 47 (89%) by the standard technique.  相似文献   
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OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed.  相似文献   
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