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51.
Epidemiological studies designed to detect lung cancer risk and other health effects in communities surrounding arsenic-producing copper smelters were reviewed. The studies were about evenly divided in finding deleterious and 'beneficial' effects of arsenic. All of the studies had insufficient statistical power to detect the small increases in risk that may occur. Even the most powerful studies were not designed to detect relative risks less than about 1.2 and the majority of the studies had little power to detect risks under 2.0. Confidence intervals for the relative risks from these studies were not very useful in putting an upper bound on adverse effects of arsenic. Sources of bias and other difficulties with community health studies are also discussed. We argue that these studies may be a good and economical first investigation but, due to a lack of power, null findings do not rule out the possibility of excess risks that may be significant from a public health viewpoint. 相似文献
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The relationship between type of biopsy-mastectomy procedure and four sets of independent variables (physician, patient, hospital and tumor characteristics) was examined for 993 locally-staged breast cancer patients diagnosed between 1974 and 1981 in 13 counties of western Washington State. Time trends were also investigated. Cases were selected from records of a population-based cancer registry. The frequency of the two-step procedure, in which biopsy and surgery occur on different days, increased from 28 to 57% during the 8-year study period. Use of the two-step procedure was associated with younger age of the patient, less suspicious symptoms or mammogram results, younger physician cohorts and hospitals with government and health maintenance organization proprietorship. These relationships remained unchanged after controlling for potentially confounding variables. There were also substantial differences between individual hospitals in the frequency of the two-step procedure, suggesting differing schools of thought in different locales. 相似文献
54.
Biologic prosthesis reduces recurrence after laparoscopic paraesophageal hernia repair: a multicenter, prospective, randomized trial 总被引:18,自引:0,他引:18
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Oelschlager BK Pellegrini CA Hunter J Soper N Brunt M Sheppard B Jobe B Polissar N Mitsumori L Nelson J Swanstrom L 《Annals of surgery》2006,244(4):481-490
OBJECTIVE: Laparoscopic paraesophageal hernia repair (LPEHR) is associated with a high recurrence rate. Repair with synthetic mesh lowers recurrence but can cause dysphagia and visceral erosions. This trial was designed to study the value of a biologic prosthesis, small intestinal submucosa (SIS), in LPEHR. METHODS: Patients undergoing LPEHR (n = 108) at 4 institutions were randomized to primary repair -1 degrees (n = 57) or primary repair buttressed with SIS (n = 51) using a standardized technique. The primary outcome measure was evidence of recurrent hernia (> or =2 cm) on UGI, read by a study radiologist blinded to the randomization status, 6 months after operation. RESULTS: At 6 months, 99 (93%) patients completed clinical symptomatic follow-up and 95 (90%) patients had an UGI. The groups had similar clinical presentations (symptom profile, quality of life, type and size of hernia, esophageal length, and BMI). Operative times (SIS 202 minutes vs. 1 degrees 183 minutes, P = 0.15) and perioperative complications did not differ. There were no operations for recurrent hernia nor mesh-related complications. At 6 months, 4 patients (9%) developed a recurrent hernia >2 cm in the SIS group and 12 patients (24%) in the 1 degrees group (P = 0.04). Both groups experienced a significant reduction in all measured symptoms (heartburn, regurgitation, dysphagia, chest pain, early satiety, and postprandial pain) and improved QOL (SF-36) after operation. There was no difference between groups in either pre or postoperative symptom severity. Patients with a recurrent hernia had more chest pain (2.7 vs. 1.0, P = 0.03) and early satiety (2.8 vs. 1.3, P = 0.02) and worse physical functioning (63 vs. 72, P = 0.03 per SF-36). CONCLUSIONS: Adding a biologic prosthesis during LPEHR reduces the likelihood of recurrence at 6 months, without mesh-related complications or side effects. 相似文献
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Large-cell lymphoma of the spleen: CT appearance 总被引:2,自引:0,他引:2
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Hypersensitivity pneumonitis: evaluation with CT 总被引:4,自引:0,他引:4
Thirteen chest radiographs and computed tomographic (CT) scans obtained from 11 patients with hypersensitivity pneumonitis were reviewed. The CT findings were correlated with open lung biopsy findings in seven patients. The two patients with acute hypersensitivity pneumonitis showed air-space opacification on CT scans. An open lung biopsy, done in one of these patients, demonstrated noncaseating granulomas and filling of the air spaces with macrophages. The nine patients with subacute hypersensitivity pneumonitis showed small, rounded opacities and patchy air-space opacification on CT scans. These findings reflected the histologic findings, which consisted of interstitial pneumonitis, cellular bronchiolitis, and small, noncaseating granulomas. The six patients with symptoms for 12 months or longer also showed irregular linear opacities on CT scans, corresponding to areas of fibrosis. CT scans were superior to radiographs in helping to assess the type and extent of abnormalities, and high-resolution CT scans were superior to conventional CT scans. 相似文献
59.
沙赛普肽注射液的细菌内毒素检测 总被引:2,自引:0,他引:2
目的:用鲎试剂检测沙赛普肽注射液中的细菌内毒素。方法:采用鲎试法(LT)与家兔法(RT)对沙赛普肽注射液进行细菌内毒素检测。结果:两种方法检查结果一致,用直接稀释法排除细菌内毒素的干扰。结论:以鲎试法用于控制沙赛普注射液的热原方法可行。 相似文献
60.
The dental implications of bisphosphonates and bone disease 总被引:3,自引:0,他引:3