首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   204篇
  免费   22篇
  国内免费   8篇
  2024年   1篇
  2022年   1篇
  2021年   5篇
  2020年   4篇
  2019年   6篇
  2018年   9篇
  2017年   10篇
  2016年   5篇
  2015年   1篇
  2014年   3篇
  2013年   20篇
  2012年   5篇
  2011年   5篇
  2010年   7篇
  2009年   7篇
  2008年   7篇
  2007年   14篇
  2006年   11篇
  2005年   6篇
  2004年   10篇
  2003年   3篇
  2002年   3篇
  2001年   7篇
  2000年   2篇
  1999年   2篇
  1998年   3篇
  1996年   2篇
  1995年   2篇
  1994年   6篇
  1993年   6篇
  1992年   6篇
  1991年   1篇
  1990年   6篇
  1989年   4篇
  1988年   3篇
  1987年   1篇
  1986年   4篇
  1985年   4篇
  1984年   5篇
  1983年   3篇
  1982年   5篇
  1981年   4篇
  1980年   2篇
  1979年   5篇
  1978年   4篇
  1977年   3篇
  1976年   1篇
排序方式: 共有234条查询结果,搜索用时 15 毫秒
51.
通过对本地一所三级甲等医院进行的围手术期抗菌药物的干预对照研究,用SPSS软件对470个手术病例的调查资料进行了统计分析,加强抗菌药物的用药管理及进行用药干预,能在对住院时间和手术切口感染率无影响的同时,明显降低手术病例的药品费用,特别是抗茵药品的费用,减轻患者负担。  相似文献   
52.
The acquisition of a negative evaluation of a fictitious minority social group in spite of the absence of any objective correlation between group membership and negative behaviours was described by Hamilton and Gifford (1976) Hamilton, D. L. and Gifford, R. K. 1976. Illusory correlation in intergroup perception: A cognitive basis of stereotypic judgments. Journal of Experimental Social Psychology, 12: 392407. [Crossref], [Web of Science ®] [Google Scholar] as an instance of an illusory correlation. We studied the acquisition and attenuation through time of this correlation learning effect. In two experiments we asked for participants’ judgements of two fictitious groups using an online version of a group membership belief paradigm. We tested how judgements of the two groups changed as a function of the amount of training they received. Results suggest that the perception of the illusory correlation effect is initially absent, emerges with intermediate amounts of absolute experience, but diminishes and is eliminated with increased experience. This illusory correlation effect can be considered to reflect incomplete learning rather than a bias due to information loss in judgements or distinctiveness.  相似文献   
53.
大学生亲社会倾向、亲社会推理以及它们的相关模式   总被引:8,自引:0,他引:8  
《心理科学》2004,27(2):329-332
采用《亲社会倾向测量》和《亲社会推理客观测量》研究了17至20岁大学生的六类亲社会倾向和亲社会推理的状况。发现大学生将利他的亲社会倾向列为六类倾向中的首位,接下来依次是紧急的、情绪性的、依从的、匿名的和公开的亲社会倾向;在亲社会推理五种类型中大学生选择比率最高的是内化价值定向的推理,接下来依次是刻板定向、需要定向和享乐主义定向的推理,所占比率最低的是赞扬定向的推理;六类亲社会倾向与亲社会推理之间具有特定的棚关模式.利他的和匿名的亲社会倾向与内化价值定向和刻板定向的推理正相关、与享乐主义定向及赞扬定向的推理负相关,公开的亲社会倾向与赞扬定向的推理正相关、与需要定向的推理负相关。跨文化比较证实,中美大学生的上述三个方面表现出一定的差异。  相似文献   
54.
When the underlying distribution is discrete with a limited number of categories, methods for interval estimation of the intraclass correlation which assume normality are theoretically inadequate for use. On the basis of large sample theory, this paper develops an asymptotic closed-form interval estimate of the intraclass correlation for the case where there is a natural score associated with each category. This paper employs Monte Carlo simulation to demonstrate that when the underlying intraclass correlation is large, the traditional interval estimator which assumes normality can be misleading. We find that when the number of classes is 20, the interval estimator proposed here can generally perform reasonably well in a variety of situations. This paper further notes that the proposed interval estimator is invariant with respect to a linear transformation. When the data are on a nominal scale, an extension of the proposed method to account for this case, as well as a discussion on the relationship between the intraclass correlation and a kappa-type measure defined here and on the limitation of the corresponding kappa-type estimator are given.The authors wish to thank the Editor, the Associate Editor, and the three referees for many valuable comments and suggestions to improve the clarity of this paper. The works for the first, the third, and the fourth authors were partially supported by grant #R01AR43025-01 from the National Institute of Arthritis and Musculoskeletal and Skin Diseases.  相似文献   
55.
Genetic counseling for Gaucher disease is complicated by the vast degree of clinical heterogeneity encountered in the disorder. Recent advances in our understanding of the molecular genetics of Gaucher disease are particularly relevant to genetic counseling. Although the identification of mutations in the glucocerebrosidase gene has enabled genotypic screening of Gaucher patients, the ability to reliably predict patient outcome on the basis of DNA studies is often limited. An appreciation of both the spectrum of clinical manifestations in Gaucher patients and the limitations of the available genotypic information is necessary when counseling patients, families and at-risk individuals.  相似文献   
56.
A family of solutions for linear relations amongk sets of variables is proposed. It is shown how these solutions apply fork=2, and how they can be generalized from there tok3.The family of solutions depends on three independent choices: (i) to what extent a solution may be influenced by differences in variances of components within each set; (ii) to what extent the sets may be differentially weighted with respect to their contribution to the solution—including orthogonality constraints; (iii) whether or not individual sets of variables may be replaced by an orthogonal and unit normalized basis.Solutions are compared with respect to their optimality properties. For each solution the appropriate stationary equations are given. For one example it is shown how the determinantal equation of the stationary equations can be interpreted.  相似文献   
57.
Three methods for dual scaling of successive categories data are formulated. They are mathematically equivalent, and provide an appropriate technique to determine stimulus values and category boundaries on a joint scale, a problem that Nishisato's method (1980a) failed to handle. This study was supported by the Natural Sciences and Engineering Research Council of Canada (Grant No. A7942) to S. Nishisato. Comments on the earlier draft from anonymous reviewers were most helpful and much appreciated.  相似文献   
58.
A distinction is drawn between redundancy measurement and the measurement of multivariate association for two sets of variables. Several measures of multivariate association between two sets of variables are examined. It is shown that all of these measures are generalizations of the (univariate) squared-multiple correlation; all are functions of the canonical correlations, and all are invariant under linear transformations of the original sets of variables. It is further shown that the measures can be considered to be symmetric and are strictly ordered for any two sets of observed variables. It is suggested that measures of multivariate relationship may be used to generalize the concept of test reliability to the case of vector random variables.  相似文献   
59.
A measure of multiple rank correlation,T y.12 2, is proposed for the situation with no tied observations in the variables. The measure is a weighted average of two squared Kendall taus. It is shown thatT y.12 2 is equivalent to a statistic previously proposed by Moran and thus a new interpretation is given to Moran's statistic.The author wishes to thank Nancy Anderson, Willard Larkin, and Kent Norman for their helpful comments.  相似文献   
60.
The validity of a test is often estimated in a nonrandom sample of selected individuals. To accurately estimate the relation between the predictor and the criterion we correct this correlation for range restriction. Unfortunately, this corrected correlation cannot be transformed using Fisher'sZ transformation, and asymptotic tests of hypotheses based on small or moderate samples are not accurate. We developed a Fisherr toZ transformation for the corrected correlation for each of two conditions: (a) the criterion data were missing due to selection on the predictor (the missing data were MAR); and (b) the criterion was missing at random, not due to selection (the missing data were MCAR). The twoZ transformations were evaluated in a computer simulation. The transformations were accurate, and tests of hypotheses and confidence intervals based on the transformations were superior to those that were not based on the transformations.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号