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41.
腹主动脉瘤的外科治疗决策   总被引:1,自引:0,他引:1  
腹主动脉瘤破裂是最常见、最凶险的疾病之一。提高对其治疗的临床决策水平至关重要。比较传统开腹修复治疗和血管腔内修复治疗的优缺点,以最佳证据为指导,选出最佳方案应用于临床实践。以人为本,做出科学决策,从而降低医疗费用及提高疗效及患者生活质量。  相似文献   
42.
Distribution-free tests of stochastic dominance for small samples   总被引:1,自引:0,他引:1  
One variable is said to “stochastically dominate” another if the probability of observations smaller than x is greater for one variable than the other, for all x. Inferring stochastic dominance from data samples is important for many applications of econometrics and experimental psychology, but little is known about the performance of existing inferential methods. Through simulation, we show that three of the most widely used inferential methods are inadequate for use in small samples of the size commonly encountered in many applications (up to 400 observations from each distribution). We develop two new inferential methods that perform very well in a limited, but practically important, case where the two variables are guaranteed not to be equal in distribution. We also show that extensions of these new methods, and an improved version of an existing method, perform quite well in the original, unlimited case.  相似文献   
43.
Numbers are fundamental entities in mathematics, but their cognitive bases are unclear. Abundant research points to linear space as a natural grounding for number representation. But, is number representation fundamentally spatial? We disentangle number representation from standard number-to-line reporting methods, and compare numerical estimations in educated participants using line-reporting with three nonspatial reporting conditions (squeezing, bell-striking, and vocalizing). All three cases of nonspatial-reporting consistently reproduced well-established results obtained with number-line methods. Furthermore, unlike line-reporting—and congruent with the psychophysical Weber–Fechner law—nonspatial reporting systematically produced logarithmic mappings for all nonsymbolic stimuli. Strikingly, linear mappings were obtained exclusively in conditions with culturally mediated elements (e.g., words). These results suggest that number representation is not fundamentally spatial, but builds on a deeper magnitude sense that manifests spatially and nonspatially mediated by magnitude, stimulus modality, and reporting condition. Number-to-space mappings—although ubiquitous in the modern world—do not seem to be rooted directly in brain evolution but have been culturally privileged and enhanced.  相似文献   
44.
The authors demonstrate how collecting quantitative data via psychometrically sound quantitative instruments during the qualitative interview process enhances interpretations by helping researchers better contextualize qualitative findings, specifically through qualitative dominant crossover mixed analyses. They provide an example of this strategy, whereby a baseline was established using a quantitative scale and normative data to help interpret qualitative interviews, resulting in what they call a mixed methods interview. Philosophical and practical implications are discussed.  相似文献   
45.
Qualitative research is experiencing a resurgence within the field of psychology. This study aimed to explore the range of attitudes towards qualitative research in psychology held by students and academics, using the model of attitudes by Eagly and Chaiken as a framework. Twenty‐one psychology students and academics were interviewed about their attitudes towards qualitative research. Interviews were transcribed and analysed using thematic analysis. While qualitative research was described as inherent to the psychology profession and useful for generating rich data, some participants felt that this approach was not well respected or considered as legitimate as quantitative methods. Reflecting common misperceptions about qualitative research, participants also expressed concerns that qualitative research was too subjective and had limited generalisability. Furthermore, some participants felt that they lacked the skills and confidence necessary to conduct qualitative research. Large investments in time and resources were identified as barriers to undertaking qualitative research. Identifying attitudes towards qualitative research provides a basis for future work in dispelling myths, promoting attitudinal change and increasing both the use and teaching of qualitative approaches in psychology.  相似文献   
46.
萨顿提出的新人文主义观,分析批判了科学与人文的分裂对立,指出科学人性化是科学与人文融合的方法,其人性化的科学现有利于我们今天深度解读、审视医学的人性化,张扬价值理性,在实践中克服目前医学异化的倾向,开掘医学和人文融合的路径,实现医学人性化的真正回归。  相似文献   
47.
This fascinating autobiography and multifaceted case history in neuroscience research is accessible to laymen and potentially instructive to working scientists. Kandel takes the reader through his thought processes as he describes experiments that led to some of the past decades'' major neuroscience discoveries (some highlights of which are summarized in the review''s Appendix), and eventually to his Nobel Prize. The review analyzes some of the terminological and conceptual issues that have often inhibited communication between behavior analysts and neuroscientists, with special attention to some of Bennett and Hacker''s admonitions viewed from the perspective of language evolution and linguistics. The review then discusses opportunities for behavior analysts to collaborate with neuroscientists by applying behavioral contingency analysis to help specify the independent variables of neuroscience experiments described by Kandel. Finally, it examines Kandel''s provocative heuristics for locating important research problems, and the lessons that can be gleaned from the book regarding the attributes of potentially great achievers.  相似文献   
48.
改革开放的三十年所取得的成功的经验之一,就是找到一个适合中国国情的发展观,即从“发展是硬道理”到“发展是第一要务”从而确立了科学发展观。“发展是硬道理”向我们表明,在发展过程中,“软道理”要服从“硬道理”,无论在何种情况下,我们都是坚持马克思主义历史观,把经济发展看作是社会发展的基础,同时在经济发展中兼顾其他各个方面的发展。  相似文献   
49.
浅谈医学科研思维的逻辑性   总被引:2,自引:0,他引:2  
医学科研思维过程中最重要的就是医学假说的提出、验证,推理和遵守逻辑思维的过程。它以抽象的概念、判断、推理为思维形式,通过分析、综合、比较、分类等多种逻辑思维方法进行操作,以达到它的最终目的。逻辑思维能力对于医学科研工作者是至关重要的,医学科研工作者应该不断加强逻辑修养,不断提升科研思维水准。  相似文献   
50.
Redundant publication in biomedical sciences is the presentation of the same information or data set more than once. Forms of redundant publication include “salami slicing”, in which similar text accompanies data presented in disaggregated fashion in different publications and “duplicate or multiple publication” in which identical information is presented with a virtually identical text. Estimates of prevalence of the phenomenon put it at 10 to 25% of published literature. Redundant publication can be considered unethical, or fraudulent, when the author(s) attempt to conceal the existence of duplicate publication from editors and readers. Redundant publication in the area of clinical trials is potentially dangerous as it tends to overestimate the effects of interventions. The scientific community at large and governments should take urgent steps to safeguard the public from the possible effects of fraudulent multiple publications.  相似文献   
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