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31.
目的:探讨重症急性呼吸综合征(SARS)与细菌性典型肺炎胸部CT特征的异同.方法:回顾性分析28例SARS胸部CT表现与细菌性典型肺炎做对比结果:本组28例患者肺部病变初期多为单发病灶,在右侧外带胸膜下常见。片状磨玻璃样密度病变影存在于各期,而细菌性典型肺炎未见、发病初期和进展期肺容积变小?而细菌性典型肺炎多无此特点。进展期大多数发展为双肺由下至上痛变、恢复期病变由最晚受侵部位消退,遗留纤维化多为最早发生病变部位?而典型肺炎多从近肺门侧开始吸收,进展期局限的肺段、肺叶发展至多个肺叶、肺段,进展较迅速。而细菌性典型肺炎多为单独的肺叶、肺段.恢复期由弥漫性多发病变转变为局限病变,部分病人有肺部纤维化发生,而细菌性典型肺炎大多数吸收较完全,不遗留肺纤维化。结论:SARS所存在的急性间质性肺炎和急性肺炎可利用CT动态检查较准确地与细菌性典型肺炙加以区别。 相似文献
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Scott Lozanoff Barbara A. Long David L. Singer John J. Deptuch 《Journal of clinical periodontology》1992,19(8):553-559
Deposits of dental plaque or calculus are typically quantified using planimetric techniques. However, error is introduced into a quantitative analysis of plaque deposits using these methods, since they require a significant amount of human intervention. The purpose of this study is to describe and validate a computerized imaging routine which has the potential to objectively identify material on dental roots and measure the area covered by these deposits. Dentiform teeth with simulated plaque were videorecorded. A computer routine was developed based on a flood-fill algorithm which analyzed images of the dentiform teeth and determined the amount of simulated plaque on their root surfaces. Results showed that the dentiform teeth and their simulated plaque patterns are duplicated by the imaging routine in a rapid and reliable fashion. The system shows a high degree of accuracy with an average error factor of only 0.58%. As well, the system enables precise reproducibility with an average error factor of only 0.71%. 相似文献
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Fifty-five students and staff at Robert Gordon's Institute of Technology completed a food frequency questionnaire and then weighed their food for one week. Several methods of calculating nutrient intakes from the questionnaire are compared to results from the weighed inventory. Intakes of energy and several nutrients calculated using estimated typical portion weights were less than those derived from the weighed inventory. Food groups contributing to the apparent under-estimation have been identified. A further method of calculation involved derivation of a factor for each food group such that the frequency estimated from the questionnaire multiplied by the factor equalled the average weight of the foods in that group that had been eaten. Using these factors instead of the typical portion weights resulted in closer agreement to the weighed inventory method, but the difference ranged from positive for some groups to negative for others. Use of separate factors for each group of subjects reduced the range of differences to the weighed inventory method. 相似文献
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A. T. McWILLIAMS 《Medical education》1988,22(2):99-103
Medical students are allocated little curriculum time for exposure to expert systems. ESTA, a computer model of an expert system, was developed to make best use of this time. The nature of the students' interaction with ESTA is described, and their reactions to the expert system concepts and the place of expert systems in medicine are presented. A discussion of these reactions draws some conclusions about teaching expert systems in particular, and computers in general, in the basic medical course. 相似文献
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药物构效关系研究与药物设计中常用计算机软件 总被引:3,自引:0,他引:3
分子力学、量子化学和分子图形学是研究有机药物分子电子特性、空间性质及其与受体相互作用的有力工具。现扼要介绍国内外较常用的量子化学和分子力学及分子图形学有关计算机程序的应用特性。 相似文献
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Summary: The Internet contains a vast amount of medically relevant information. In order to access this information, however, many networks require one to master applications written in UNIX, an operating system considered by many not to be user friendly. Although these tools may be available on the campus, it is difficult to teach their use unless there is some immediate benefit to the already busy user. From that standpoint, it is important for instructors to realize that common UNIX applications can be utilized as classroom tools to significantly enhance the learning experience by facilitating teacher/student communication. Also, whilst the student enjoys greater communication with the instructor (and with other students) he/she is also becoming adept at using information management tools. 相似文献