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1.
A fundamental prerequisite of population health research is the ability to establish an accurate denominator. This in turn requires that every individual in the study population is counted. However, this seemingly simple principle has become a point of conflict between researchers whose aim is to produce evidence of disparities in population health outcomes and governments whose policies promote (intentionally or not) inequalities that are the underlying causes of health disparities. Research into the health of asylum seekers is a case in point. There is a growing body of evidence documenting the adverse affects of recent changes in asylum-seeking legislation, including mandatory detention. However, much of this evidence has been dismissed by some governments as being unsound, biased and unscientific because, it is argued, evidence is derived from small samples or from case studies. Yet, it is the policies of governments that are the key barrier to the conduct of rigorous population health research on asylum seekers. In this paper, the authors discuss the challenges of counting asylum seekers and the limitations of data reported in some industrialized countries. They argue that the lack of accurate statistical data on asylum seekers has been an effective neo-conservative strategy for erasing the health inequalities in this vulnerable population, indeed a strategy that renders invisible this population. They describe some alternative strategies that may be used by researchers to obtain denominator data on hard-to-reach populations such as asylum seekers.  相似文献   
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Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
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To further characterize the incidence and morbidity of recurrent carotid stenosis, we reviewed 184 consecutive carotid endarterectomies performed in a university hospital between August 1983 and January 1988, in patients followed after operation with serial duplex ultrasonography. Recurrent stenosis of greater than 50% diameter reduction developed in eleven arteries (6.0%) at a mean interval of 10.2 +/- 7.8 months. Three of the eleven (1.6% of the total) had associated transient ischemic attack, and none had strokes. Restenosis was significantly more frequent in diabetic patients than in nondiabetic patients (13.3% vs 4.5%; p less than 0.05); and among patients whose primary stenoses had been symptomatic compared to asymptomatic (11.0% vs 1.5%; p less than 0.02). No statistically significant association with restenosis could be established for gender, hypertension, or smoking. Completion angiography and/or Doppler spectral analysis had been performed, and results were normal at the primary operation in 10 of the 11 patients. Only six of 184 arteries (3.3%) had vein patch closure, but none of these restenosed. Uneventful reoperation with patch closure was performed in three patients with transient ischemic attacks and two with preocclusive restenoses. Lesions were myointimal hyperplasia in four and atheroma in one. Three of the unoperated restenoses have shown regression on duplex scanning, but a fourth progressed to asymptomatic occlusion. Carotid restenosis is uncommon, even without routine use of vein patch angioplasty. Reoperation should be reserved for patients with associated symptoms or greater than 80% restenosis.  相似文献   
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The simultaneous occurrence of renovascular hypertension and an adrenocortical adenoma is a rare entity. The case of a 64-year-old woman who underwent an aortorenal bypass graft for renovascular hypertension requiring a multidrug antihypertensive regimen is presented. Persistently elevated blood pressures in the postoperative period prompted further workup for other causes of hypertension. Laboratory evaluation showed hyperaldosteronism and hyporeninemia despite enalapril administration. Abdominal computerized tomography (CT) revealed a left adrenal mass which, on surgical removal, was found to be a cortical adenoma. Subsequently, her antihypertensive therapy has been reduced to a single agent. Previous authors have described only four patients with malignant hypertension who had the rare clinical combination of renal artery stenosis and an aldosteronoma. This case reemphasizes the critical need for a thorough search for other surgically correctable lesions in those patients who remain severely hypertensive after the "definitive" operation.  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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Nosocomial diarrhea caused by Clostridium difficile causes significant morbidity and mortality in an increasing proportion of hospitalized patients annually. This case-control study of patients admitted to the hematology-oncology ward of a tertiary academic medical center over a 2-year period demonstrates that patients with Clostridium difficile-associated diarrhea (CDAD) were 22 times more likely than ward-matched controls with diarrhea to have received any antibiotic either during hospitalization or in the month preceding admission (p < 0.005), and they were nearly three times as likely as controls to have received a cephalosporin during the same period (p < 0.005). Diarrhea among lung cancer patients was approximately three times more likely to be caused by this organism than to be due to other causes (p = 0.04). A trend towards CDAD patients receiving higher numbers of different antibiotics during hospitalization (3.3 vs. 2.6, 95%CI −1.42–0.02, p = 0.06) was noted. Administration of interleukin-2 either during hospitalization or in the 30 days preceding admission was seven times more likely to have occurred in CDAD cases (p = 0.04), raising the question of whether or not this agent increases risk.  相似文献   
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