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Prediction of choledocholithiasis using a pocket microcomputer   总被引:4,自引:0,他引:4  
A computerized method, using a small pocket computer, has been used to predict the presence of choledocholithiasis in a prospective series of 239 patients undergoing cholecystectomy. From an initial data base of 424 patients 36 factors were evaluated and the most important 2 of these were determined by multivariate analysis for use in the prospective analysis. Satisfactory operative cholangiograms were a prerequisite to evaluation of the statistical method and were obtained in 90.4 per cent of cases. Using the computerized method a common bile duct stone would have been overlooked in only 1 patient but 17 unnecessary explorations would have been carried out. The overall accuracy of the computerized method was 92.5 per cent. When the method was applied to a further study of 97 patients from a separate centre the overall accuracy was 85.6 per cent. If the method was used to aid selective use of operative cholangiography, cholangiograms would be performed in 20 per cent and stones would be overlooked in less than 1 per cent.  相似文献   
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Federal regulations prescribe distinct protections for children participating in research studies. Procedures for collecting tissue specimens from children solely for research purposes must pose no more than a minor increase over minimum risk, thereby limiting the approvable correlative biologic studies to evaluate molecularly targeted agents in children with cancer. Ethical issues arise when approvable correlative studies are a mandatory component of an early-phase pediatric clinical trial of new anticancer agents. The National Cancer Institute Cancer Therapy Evaluation Program sponsored a workshop in 2002 to discuss tissue collection for correlative biologic studies in early-phase childhood cancer clinical studies of molecularly targeted agents. Workshop participants recommended the following: (1) tissue specimens for correlative studies should provide vital clinical and scientific results to qualify for early-phase pediatric study consideration; (2) parents should receive a realistic appraisal of the risks, requirements, and potential for benefit of phase I protocol participation; (3) investigators should clearly distinguish clinically necessary procedures from research procedures of no benefit to the child to improve correlative study informed consent; and (4) participation in correlative research studies included in clinical trials generally should be voluntary. The need to acquire important biologic data regarding new molecular agents will challenge the ingenuity of pediatric cancer researchers, necessitating the application of highly sensitive laboratory assay methods, new imaging procedures, and preclinical models of childhood cancer. Such innovative methods can allow necessary scientific information to be obtained while simultaneously respecting the protections appropriately afforded to children participating in research studies and minimizing the burden of research participation for children with cancer and their families.  相似文献   
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Individual larvae, pupae, female adults, and adult body parts of Anopheles arabiensis Patton and An. gambiae Giles were stored for 1 mo either in isopropanol at room temperature, over a desiccant at room temperature, or at -70 degrees C. DNA was extracted, digested with EcoR1 restriction enzyme, subjected to electrophoresis in agarose gel, transferred to filters, then hybridized to a 32P-labeled rDNA probe. There was no difference among storage treatments in the proportion of correctly identified samples. First instars were not identifiable. Pupae and female adults were more likely to be identified than earlier life history stages. Nonetheless, the probe identified greater than 75% of second instars, 94% of third instars, and 74% of fourth instars. There were no differences between the species in the proportion of identifiable samples for any life history stage.  相似文献   
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This article updates a paper published in this journal more than a decade ago. We detail the ensuing decade's developments in the treatment of obesity, reviewing innovations, established techniques, and the current status of behavior modification. We evaluate newer developments, such as anorectic drugs, very low calorie diets, and intragastric balloon bezoars, and we describe other approaches to the treatment of obesity, such as residential and comprehensive outpatient programs. We conclude by recommending a multidisciplinary approach to this complex problem.  相似文献   
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