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991.
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Control of hypertension is well established for the primary prevention of stroke. Prior studies, on the other hand, conflict over whether hypertension remains a risk factor for recurrent stroke and if blood pressure reduction is associated with better outcomes in this subset of patients. We review current evidence regarding the role of BP lowering for primary and secondary prevention of stroke. Current evidence amassed from both primary and secondary prevention trials demonstrate that BP reduction is a crucial common element in overall reduction of stroke risk.  相似文献   
993.
Gallbladder cancer, the commonest malignancy of the biliary tract worldwide, is common in northern India. It can be clinically obvious, an unexpected finding at laparotomy, detected incidentally on histological examination or may be missed only to present with recurrence during follow up. US, CECT, uppeer gastro-intestinal endoscopy, and laparoscopy are useful for diagnosis and staging. We have adopted a 'middle path'--between pessimistic nihilism of the West and aggressive radicalism of Japan--of management, i.e., extended cholecystectomy for early disease confined to the gallbladder and hepato-dudodenal ligament, and non-surgical palliation for advanced disease. The aetiological role of gallstones in the causation of gallbladder cancer needs to be investigated to decide the place of prophylactic cholecystectomy, if any.  相似文献   
994.
Inhibition of cyclooxygenase-2 (COX2) by non-steroidal anti-inflammatory drugs (NSAID) is known to suppress skin carcinogenesis. It was further suggested that inhibition of COX2-derived prostaglandins by NSAIDs could reduce levels of putative endogenous ligands of peroxisome proliferator-activated receptor-beta (PPARbeta), and these ligands could potentiate tumorigenesis. However, it is currently unclear whether ligand activation of PPARbeta either inhibits or potentiates carcinogenesis. The present studies were designed to examine the mechanism of NSAID-mediated chemoprevention in skin, and, in particular, to determine the role of PPARbeta in this process. A two-stage skin carcinogenicity bioassay was performed using wild-type and PPARbeta-null mice that were fed either a control diet or one containing 0.32 g sulindac/kg diet. Significant inhibition of chemically induced skin carcinogenesis was observed in both wild-type and PPARbeta-null mice, and this was associated with a marked decrease in the concentration of skin prostaglandins including PGE(2) and PGI(2). Results from these studies demonstrate that inhibition of COX2 by dietary sulindac in mouse skin can effectively inhibit chemically induced skin carcinogenesis, and suggest that the mechanism underlying this chemopreventive effect is independent of PPARbeta. Additionally, results from these studies do not support the hypothesis that ligand activation of PPARbeta by COX-derived metabolites potentiates chemically induced skin carcinogenesis.  相似文献   
995.
The purpose of this study is to describe the evaluation of a sexual history-taking curriculum and correlates of student performance during a Clinical Skills Assessment. Reading assignments, small group discussions, a Saturday Sex workshop and performance on a Clinical Skills Assessment were evaluated. Students most favorably rated the workshop and least favorably rated the reading assignments. Eighty-four percent of students asked at least one sexual history question on the Clinical Skills Assessment. We were unable to identify any independent predictors of sexual history-taking behavior.  相似文献   
996.
Laparoscopic surgery is an established treatment modality for adrenal disease, especially pheochromocytomas. We describe the successful excision of an extra-adrenal pheochromocytoma using a novel transperitoneal, transmesocolic approach. The tumor was located inferior to the left renal hilum in the para-aortic region and was found bulging through the descending mesocolon at laparoscopy. The tumor was removed without mobilization of the descending colon.  相似文献   
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BACKGROUND: Skillful surgical care demands proper patient assessment and decision-making. These skills are honed through long hours and years of clinical practice. A decrease in work hours is reducing the number of cases managed by medical students and residents. We have developed a set of interactive, web-based teaching modules to help fill this gap. MATERIALS AND METHODS: The modules aim to teach surgical decision-making in a convenient, nonthreatening manner. Surgical case material is presented in a graphically rich environment, including video and sound to enhance realism. At the end of each web-page, the user must make a management decision. The correct answer is subsequently provided with immediate feedback. Medical students used and evaluated the modules during their surgical clerkships. Additionally, students took a pretest and 1-week delayed posttest after completing the modules to assess the program's efficacy. RESULTS: Eight modules involving pediatric and general surgery have been completed. Medical students gave high ratings to the quality of the modules and found the interactive format both engaging and educationally effective. Eighty-seven percent of medical students rated the program's educational value as above average to excellent. On pre- and posttest analysis, students' scores improved an average of 24.8% (P < 0.001). CONCLUSION: Students enjoy web-based educational material. Additional modules covering a range of surgical topics are in development. Web-based modules appear to be an effective clinical teaching tool, well-suited for integration into the clinical curriculum.  相似文献   
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