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31.
Teaching of medical ethics 总被引:1,自引:0,他引:1
Teaching medical ethics in Manchester within the introductory course of obstetrics and gynaecology is a joint activity with the Centre for Social Ethics and Policy. This interdisciplinary teaching has evolved through lecture sessions with small-group discussions dealing with topics of interest in human reproduction. The small-group discussion have been replaced by an open debate conducted by the students. Their own involvement and participation and an exposure to the disciplines of the humanities has broadened their approach to different ways of problem-solving of these real issues. 相似文献
32.
K.M. SIVANANDAIAH V.V. SURESHBABU S.C. SHANKARAMMA 《Chemical biology & drug design》1995,45(4):377-379
Deprotection of the tert-butoxycarbonyl group during solid-phase synthesis of peptides can be conveniently and efficiently carried out using a neutral reagent, silicon tetrachloride/sodium iodide (iodotrichlorosilane). This simple and rapid method has been advantageously employed during the solid-phase synthesis of the pituitary hormone, oxytocin. 相似文献
33.
本文介绍了不同的影像色彩模式和影像文件常见存储格式的特点及其在应用上的优缺点,分析了影像色彩模式、文件存储的格式与影像质量、用途的关系。 相似文献
34.
文章针对目前医学生“网络成瘾症”的现状进行了分析,并指出了产生的原因和解决问题的办法,以求达到标本兼治。最后提出三点预防医学生“网络成瘾症”的对策:一是高校及其附属医院要为医学生营造宽松愉快的学习、生活环境;二是呼吁家长关注医学生身心发展的特殊规律,建立良好的家庭环境;三是建立和完善与网络社会相应的法律法规,规范医学生的网上行为。 相似文献
35.
36.
Objectives: To validate the accuracy of using probabilistic linkage for matching de‐identified ambulance records to a state trauma registry. Methods: This was a retrospective cohort analysis. Three thousand nine hundred nineteen true matches between ambulance and state trauma registry data from 1998 to 2003 were identified by deterministic matching on trauma identification number and verified by human review. Two thousand thirty‐eight ambulance records from trauma patients not meeting criteria for a true match, and an identical number of trauma registry records randomly selected from the one local county served by a different EMS provider, were included as nonmatches. There were 17 variables considered for linkage, which included the following: age, gender, race, county, hospital, date, rural setting, call and arrival times, mechanism, penetrating injury, vital signs, intubation, and intoxication. Probabilistic linkage was used to link the two data sets, using seven different combinations of common variables (maximum, 17; minimum, 4). The sensitivity and specificity of identifying true matches and nonmatches (95% confidence intervals [95% CI]) were calculated for each combination of variables. Results: Using all 17 available variables, 3,766 of 3,919 true matches were appropriately linked (sensitivity, 96.1%; 95% CI = 95.4% to 96.7%), with eight mismatches (specificity, 99.6%; 95% CI = 99.2% to 99.8%). Sensitivity fell below 95% with < 15 variables; however, sensitivity was very dependent on the inclusion of variables with high discriminatory power. Specificity remained >98% regardless of the number of variables included. Conclusions: Probabilistic linkage is a valid method for matching ambulance records to a trauma registry without the use of patient identifiers; however, the sensitivity of identifying true matches is critically dependent on the number and type of common variables included in the analysis. 相似文献
37.
作者结合实际工作经验简要论述了英文医学科技论文写作中词的选择与搭配的问题,并就如何提高英文写作水平提出了几点建议。 相似文献
38.
Among British-qualified doctors of 1974 and 1977, about 80% held postgraduate qualifications of some kind. The commonest qualifications were DRCOG, MRCP and MRCOG. There were considerable differences between medical schools in the numbers of qualifiers taking various examinations. Apart from the MRC Psych, DRCOG and Family Planning Certificate, qualifications were more commonly held by men than women. Tables show the type of work being done 9-13 years after leaving medical school by holders of various postgraduate qualifications; e.g. 60% of MRCP holders were working in medicine or a medical specialty and 84% of FRCS holders in general surgery or a surgical specialty. Discussion deals with the plurality, specificity, variability, perceived necessity, sufficiency, international utility and career significance of British postgraduate qualifications. 相似文献
39.
介绍了一种简单有效的维纳滤波器设计过程,并采用该过程对数字化X射线影像进行滤波,试验表明:维纳滤波器能在去除图像噪声的同时较好地保留图像细节,具有实际应用价值。 相似文献
40.
Margaret Sullivan Pepe Ziding Feng Gary Longton Joseph Koopmeiners 《Statistics in medicine》2009,28(5):762-779
Development of a disease screening biomarker involves several phases. In phase 2 its sensitivity and specificity is compared with established thresholds for minimally acceptable performance. Since we anticipate that most candidate markers will not prove to be useful and availability of specimens and funding is limited, early termination of a study is appropriate, if accumulating data indicate that the marker is inadequate. Yet, for markers that complete phase 2, we seek estimates of sensitivity and specificity to proceed with the design of subsequent phase 3 studies. We suggest early stopping criteria and estimation procedures that adjust for bias caused by the early termination option. An important aspect of our approach is to focus on properties of estimates conditional on reaching full study enrollment. We propose the conditional‐UMVUE and contrast it with other estimates, including naïve estimators, the well‐studied unconditional‐UMVUE and the mean and median Whitehead‐adjusted estimators. The conditional‐UMVUE appears to be a very good choice. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献