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OBJECTIVE: To assess the dose-response, safety, and efficacy of circumferential endoscopic ablation of Barrett's esophagus (BE) by using an endoscopic balloon-based ablation device (HALO360 System). DESIGN: This study was conducted in 2 serial phases (dosimetry phase and effectiveness phase) to evaluate a balloon-based ablation device that delivers a pre-set amount of energy density (J/cm2) to BE tissue. The dosimetry phase evaluated the dose-response and the safety of delivering 6 to 12 J/cm2. The effectiveness phase used 10 J/cm2 (delivered twice [x2]) for all patients, followed by EGD with biopsies at 1, 3, 6, and 12 months. A second ablation procedure was performed if BE was present at 1 or 3 months. Patients received esomeprazole 40 mg twice a day for 1 month after ablation, and 40 mg every day thereafter. Postablation symptoms were quantified by using a 14-day symptom diary (scale, 0-100). A complete response (CR) was defined as all biopsy specimens negative for BE at 12 months. SETTING: Eight U.S. centers, between September 2003 and September 2005. PATIENTS: Patients were 18 to 75 years of age, with a diagnosis of BE (without dysplasia), with histopathology reconfirmation of the diagnosis within 6 months of enrollment. RESULTS: In the dosimetry phase, 32 patients (29 men; mean age, 56.8 years) were enrolled. Median symptom scores returned to a score of 0 of 100 by day 3. There were no dose-related serious adverse events, and the outcomes at 1 and 3 months permitted the selection of 10 J/cm2 (x2) for the subsequent effectiveness phase of the study. In the effectiveness phase, 70 patients (52 men, 18 women; mean age, 55.7 years) were enrolled. Median symptom scores returned to a score of 0 of 100 by day 4. At 12 months (n = 69; mean, 1.5 sessions), a CR for BE was achieved in 70% of patients. There were no strictures and no buried glandular mucosa in either study phase (4306 biopsy fragments evaluated). CONCLUSIONS: Circumferential ablation of nondysplastic BE by using this balloon-based ablation device can be performed with no subsequent strictures or buried glands and with complete elimination of BE in 70% of patients at 1-year follow-up.  相似文献   
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Background  

Mental health problems have become more common among young people over the last twenty years, especially in certain countries. The reasons for this have remained unclear. The hypothesis tested in this study is that national trends in young people's mental health are associated with national trends in young people's labour market.  相似文献   
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Little is known of the influence race has on the development of leg ulceration, with most studies being performed in almost exclusively white populations. As part of a wider audit of leg ulcer services, health care professionals were contacted to give details of age, sex and ethnic background of all patients who attended for treatment of leg ulceration over a one year period in an area of west London. West London Health Care Trust provides services to a population of 275000 of whom 53000 have an ethnic background from the Indian subcontinent (South Asian).In all, 280 patients were identified, of whom 264 (94%) had details of age and sex. This gave a crude ascertainment rate of 1.02 per 1000 population. Of the 264 patients, five were classified as South Asians, with one patient classified as Afro-caribbean. The Mantel Haenzsel test demonstrated a significantly higher proportion of whites suffering from leg ulceration than South Asians, giving an odds ratio of 4.43, with 95% confidence intervals between 1.94 and 10.13 (P=0.0004). The expected frequency of South Asian patients should be 23, based on rates from the white population, of which 13 would be women and 10 men. Only five South Asian men were identified, and no Asian women with leg ulceration.Reasons for this low ascertainment are two-fold. Either there is a real difference between the white and South Asian populations, or South Asian patients are not presenting for treatment. Further work must be performed to determine whether this is an effect of low prevalence, or unmet need in the community.  相似文献   
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