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Ethical challenges posed by acquired immunodeficiency syndrome (AIDS) are described. A small minority of health-care workers are refusing to treat persons with AIDS because they fear exposure, and some hospitals known to care for AIDS patients are being avoided as sites for training in the health professions. Some patients also are avoiding institutions that care for AIDS patients. The United States Department of Labor and Department of Health and Human Services have issued safety guidelines for health-care workers; the guidelines are intended to protect workers and to convince them not to shun AIDS patients. Given the high cost of care for AIDS patients, the question of whether the nation can pay for the best possible care for every patient must be dealt with. Also, the right of an individual to confidentiality must be balanced against risk to the community. To deal compassionately and justly with AIDS, courageous leadership and serious discussion of ethical issues are needed.  相似文献   
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Diagnosis of chronic Q fever is difficult. PCR and culture lack sensitivity; hence, diagnosis relies mainly on serologic tests using an immunofluorescence assay (IFA). Optimal phase I IgG cutoff titers are debated but are estimated to be between 1:800 and 1:1,600. In patients with proven, probable, or possible chronic Q fever, we studied phase I IgG antibody titers at the time of positive blood PCR, at diagnosis, and at peak levels during chronic Q fever. We evaluated 200 patients, of whom 93 (46.5%) had proven, 51 (25.5%) had probable, and 56 (28.0%) had possible chronic Q fever. Sixty-five percent of proven cases had positive Coxiella burnetii PCR results for blood, which was associated with high phase I IgG. Median phase I IgG titers at diagnosis and peak titers in patients with proven chronic Q fever were significantly higher than those for patients with probable and possible chronic Q fever. The positive predictive values for proven chronic Q fever, compared to possible chronic Q fever, at titers 1:1,024, 1:2,048, 1:4,096, and ≥1:8,192 were 62.2%, 66.7%, 76.5%, and ≥86.2%, respectively. However, sensitivity dropped to <60% when cutoff titers of ≥1:8,192 were used. Although our study demonstrated a strong association between high phase I IgG titers and proven chronic Q fever, increasing the current diagnostic phase I IgG cutoff to >1:1,024 is not recommended due to increased false-negative findings (sensitivity < 60%) and the high morbidity and mortality of untreated chronic Q fever. Our study emphasizes that serologic results are not diagnostic on their own but should always be interpreted in combination with clinical parameters.  相似文献   
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Zinc‐alpha 2‐glycoprotein (AZGP1) is involved in lipid metabolism and was suggested as a candidate prognostic biomarker in prostate cancer. To evaluate the clinical impact and relationship with key genomic alterations in prostate cancer, AZGP1 expression was analyzed by immunohistochemistry on a tissue microarray containing 11,152 prostate cancers. Data on ERG status and PTEN, 3p13, 5q21 and 6q15 deletions were available from earlier studies. AZGP1 expression was strong in benign prostatic glands but absent in 38.0% of 8,510 interpretable prostate cancers. Reduced AZGP1 expression was associated with TPMRSS2:ERG fusions, both by FISH and immunohistochemical analysis (p < 0.0001 each). For example, AZGP1 was absent in 54.6% of 2,029 ERG IHC positive but in only 28.1% of 2,398 ERG negative cancers. Irrespective of the ERG status, reduced AZGP1 expression was tightly linked to high Gleason score, advanced pathological tumor stage, positive nodal status and early PSA recurrence (p < 0.0001 each). Reduced AZGP1 expression was also strongly associated with PTEN deletions. AZGP1 immunostaining was lacking in 62.7% of 842 PTEN deleted but in only 37.3% of PTEN non‐deleted cancers but retained strong prognostic influence in both subgroups (p < 0.0001 each). The prognostic role of AZGP1 expression was also independent of Gleason score, pT stage, pN stage, surgical margin status and preoperative PSA, irrespective of whether preoperative or postoperative variables were used for modeling. In conclusion, the results of our study demonstrate that reduced AZGP1 expression is strongly related to adverse prostate cancer prognosis, independently of established clinic‐pathological variables and PTEN deletions.  相似文献   
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OBJECTIVES: To document current bicycle helmet use in Winnipeg, Manitoba and nearby rural communities, and to identify target groups for a helmet promotion campaign. METHODS: Cyclist helmet use was observed between 28 May and 20 August 1996 at a sample of urban and rural locations. Age, gender, helmet use, riding companion(s), location type, correct helmet use, and use of headphones were recorded. Univariate and multivariate analyses were performed. Adjusted odds ratios with 95% confidence intervals were calculated from the final models. RESULTS: Altogether 2629 cyclists (70% male, 30% female) were observed: 2316 at 183 urban locations and 313 at 25 rural locations, with nearly equal numbers of children and adults observed. Overall helmet use was 21.3%, with lower use in males (18.9%) than females (26.3%), despite gender only being a significant variable on multivariate analysis for children under 8 years and adults. Urban helmet use was considerably higher (22.9%) than rural use (8.9%). Helmet use increased linearly as mean neighbourhood income increased, with a nearly fourfold difference in use between the highest and lowest income neighbourhoods. Children less than 8 years old and adults had the highest, and teenagers the lowest, use. Significant predictive variables were identified separately by age category to inform targeted programming. CONCLUSIONS: We documented low helmet use in our region, emphasizing the need for a regional helmet promotion campaign as well as future helmet legislation. A marked urban-rural difference in helmet use that has not been previously reported was also identified. Target groups for a future campaign include adolescents, males, rural cyclists, and those in lower income neighbourhoods.  相似文献   
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