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991.
A reduced representation in the format of a barcode has been developed to provide an overview of the topological nature of a given protein structure from 3D coordinate file. The molecular structure of a protein coordinate file from Protein Data Bank is first expressed in terms of an alpha‐numero code and further converted to a barcode image. The barcode representation can be used to compare and contrast different proteins based on their structure. The utility of this method has been exemplified by comparing structural barcodes of proteins that belong to same fold family, and across different folds. In addition to this, we have attempted to provide an illustration to (i) the structural changes often seen in a given protein molecule upon interaction with ligands and (ii) Modifications in overall topology of a given protein during evolution. The program is fully downloadable from the website http://www.iitg.ac.in/probar/ .  相似文献   
992.
目的 分析政府补偿与监管机制改革对公立医疗卫生机构教学、科研以及学科建设的影响方法 通过对上海市闵行区的机构调查,收集并分析2008—2012年3所公立综合性医院和12家社区卫生服务中心的医学教育、科研项目、论文发表及重点学科建设状况的相关数据。结果 闵行区公立综合性医院和社区卫生服务中心的医学教育和科研能力有所提升,重点学科建设也有所加强;但仍然存在教学能力薄弱,科研水平层次偏低,缺乏高质量的重点学科等问题。结论 政府补偿与监管机制改革在一定程度上强化了公立医疗机构的医学教育、科研能力和学科建设,但未来需进一步加大对科教和学科建设的鼓励和支持力度。  相似文献   
993.
目的 归纳总结护理人员对患者实施关怀护理的组织环境因素,为护理管理者制定合理应对措施优化实施关怀护理的组织环境提供参考。方法 采用质性研究方法,对15名护理人员进行半结构式访谈,用现象学分析法进行资料分析。结果 护理人员在实际工作中感知到的对患者实施关怀护理的组织环境因素包括物理环境、心理环境、组织资源、组织制度和组织气氛。结论 关怀护理的良好实施需要组织环境的支持。  相似文献   
994.
兰科菌根真菌研究方法的概述   总被引:1,自引:0,他引:1  
兰科植物资源在全球分布广泛,其中有许多是重要的药用植物和名贵的珍稀花卉,由于具有较高的商业价值,受到各界人士的广泛关注。兰科植物生长习性的特殊性导致其在自然状态下繁殖率极低,因此难以满足市场的广泛需求。近年研究表明,几乎所有兰科植物都能与相应的菌根真菌建立共生关系,并且必须依赖于这些内生真菌才能完成其整个生活史。因而对菌根真菌在提高兰科植物生长速度和繁殖能力过程中机制的研究以及将研究成果运用于工业化育苗中将是缓解兰科植物市场供求紧张问题的关键。通过对近几年有关天麻和铁皮石斛等兰科植物的问题研究中所采用的研究方法加以阐述,以期对今后兰科菌根真菌的研究提供一定的参考。  相似文献   
995.
Fruit flies (Drosophila melanogaster) are an established model for both alcohol research and circadian biology. Recently, we showed that the circadian clock modulates alcohol sensitivity, but not the formation of tolerance. Here, we describe our protocol in detail. Alcohol is administered to the flies using the FlyBar. In this setup, saturated alcohol vapor is mixed with humidified air in set proportions, and administered to the flies in four tubes simultaneously. Flies are reared under standardized conditions in order to minimize variation between the replicates. Three-day old flies of different genotypes or treatments are used for the experiments, preferably by matching flies of two different time points (e.g., CT 5 and CT 17) making direct comparisons possible. During the experiment, flies are exposed for 1 hr to the pre-determined percentage of alcohol vapor and the number of flies that exhibit the Loss of Righting reflex (LoRR) or sedation are counted every 5 min. The data can be analyzed using three different statistical approaches. The first is to determine the time at which 50% of the flies have lost their righting reflex and use an Analysis of the Variance (ANOVA) to determine whether significant differences exist between time points. The second is to determine the percentage flies that show LoRR after a specified number of minutes, followed by an ANOVA analysis. The last method is to analyze the whole times series using multivariate statistics. The protocol can also be used for non-circadian experiments or comparisons between genotypes.  相似文献   
996.
997.
Dr. John Collier traced the discoveries that elucidated the structure and function of the anthrax toxin in his talk "Anthrax Toxin," which was part of the Microbiology Graduate Program Seminar Series at Yale School of Medicine on February 23, 2012. Dr. Collier, Professor of Microbiology and Immunobiology at Harvard University, began by noting the advantages to studying anthrax pathogenesis in a biosafety level-1 lab. This designation does not merely facilitate his research, but also reflects a larger trend of basic research being leveraged to develop translational applications. Basic research on toxin structure has led to the development of a vaccine by Dr. Collier's group. Next-generation prophylactics also may stem from recent discoveries uncovering a role for cellular cofactors that mediate toxin function. Finally, basic research into the toxin substructure has facilitated efforts to change the receptor tropism to target dysregulated cells for therapeutic purposes. The urgency around biodefense agents makes the choice of research priorities a salient issue. As such, this author submits that basic research occupies a unique and lucrative niche driving clinical applications.  相似文献   
998.
Animal models are of critical importance in biomedical research. Although rodents and lagomorphs are the most commonly used species, larger species are required, especially when surgical approaches or new medical devices have to be evaluated. In particular, in the field of perinatal medicine, they are critical for the evaluation of new pharmacologic treatments and the development of new invasive procedures in fetuses. In some areas, such as developmental genetics, reproductive biotechnologies and metabolic programming, the contribution of ruminants is essential. The current report focuses on some of the most outstanding examples of great biomedical advances carried out with ruminant models in the field of perinatal research. Experiments recently carried in our research unit using ruminants are also briefly described.  相似文献   
999.
Increasingly, US‐sponsored research is carried out in developing countries, but how US Institutional Review Boards (IRBs) approach the challenges they then face is unclear. METHODS: I conducted in‐depth interviews of about 2 hours each, with 46 IRB chairs, directors, administrators and members. I contacted the leadership of 60 IRBs in the United States (US) (every fourth one in the list of the top 240 institutions by National Institutes of Health (NIH) funding), and interviewed IRB leaders from 34 (55%). RESULTS: US IRBs face ethical and logistical challenges in interpreting and applying principles and regulations in developing countries, given economic and health disparities, and limited contextual knowledge. These IRBs perceive wide variations in developing world IRBs/RECs' quality, resources and training; and health systems in some countries may have long‐standing practices of corruption. These US IRBs often know little of local contexts, regulations and standards of care, and struggle with understandings of other cultures' differing views of autonomy, and risks and benefits of daily life. US IRBs thus face difficult decisions, including how to interpret principles, how much to pay subjects and how much sustainability to require from researchers. IRB responses and solutions include trying to maintain higher standards for developing world research, obtain cultural expertise, build IRB infrastructure abroad, communicate with foreign IRBs, and ‘negotiate’ for maximum benefits for participants and fearing ‘worst‐case scenarios’. CONCLUSIONS: US and foreign IRBs confront a series of tensions and dilemmas in reviewing developing world research. These data have important implications for increased education of IRBs/RECs and researchers in the US and abroad, and for research and practice.  相似文献   
1000.
徐宝凤  马进  代静  王斌  胡文东  冯正直 《生物磁学》2012,(32):6371-6375
目的:探讨并系统追踪研究新入伍战士在两年军营生活期间性格特征以及心理健康发展特点,揭示新兵入伍初期个性发展规律,为进一步筛查精神障碍易感新兵提供理论依据。方法:选取2010年某部冬季应征入伍新兵,采用问卷法对1366名新入伍男性战士在入伍第一年和第二年分别进行卡特尔十六种个性因素测验(16PF)的测试,采用分组测试和配对样本t检验进行统计分析。结果:研究表明,新入伍战士在第一年和第二年之间在稳定性、恃强性、兴奋性、有恒性、敢为性、怀疑性、幻想性、世故性、忧虑性、实验性、独立性、自律性和紧张性13种初级因素存在显著性变化,在适应焦虑型、内向外向型、感性用事与安详机警性、怯懦与果敢型、心理健康因素以及新环境成长能力因素等六项次级因素也有显著性差异,不同的学历和家庭背景也存在显著的变化。结论:本研究结果提示,入伍战士在两年军营生活期间其性格特征和心理健康特点均发生明显变化,而随着战士入伍时间的变化,对于部队生活的逐渐适应,其个性特征以及心理健康特点都出现了一定的变化规律,了解掌握这些心理健康发展的变化规律将有助于更科学地指导部队心理卫生服务工作,保证和提高军队战斗力。  相似文献   
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