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   345篇
  免费   25篇
  370篇
  2020年   7篇
  2019年   6篇
  2018年   6篇
  2017年   6篇
  2016年   9篇
  2015年   16篇
  2014年   6篇
  2013年   49篇
  2012年   8篇
  2011年   12篇
  2010年   8篇
  2009年   16篇
  2008年   12篇
  2007年   16篇
  2006年   9篇
  2005年   15篇
  2004年   12篇
  2003年   16篇
  2002年   14篇
  2001年   9篇
  2000年   5篇
  1999年   4篇
  1998年   4篇
  1997年   3篇
  1996年   5篇
  1995年   7篇
  1994年   3篇
  1993年   2篇
  1991年   4篇
  1990年   6篇
  1987年   5篇
  1986年   2篇
  1985年   3篇
  1984年   3篇
  1983年   4篇
  1982年   6篇
  1981年   7篇
  1980年   3篇
  1979年   3篇
  1978年   6篇
  1976年   6篇
  1975年   1篇
  1974年   3篇
  1973年   4篇
  1972年   1篇
  1971年   5篇
  1968年   1篇
  1967年   3篇
  1966年   2篇
  1958年   1篇
排序方式: 共有370条查询结果,搜索用时 8 毫秒
281.
282.
283.
This study aimed to (a) assess relationships between the Children's Depression Inventory (CDI) and DSM-oriented depression and anxiety scales of the Youth Self Report, (b) develop reliable norms for the CDI, and (c) determine CDI cutoff scores for selecting youngsters at risk for depression and anxiety. A total of 3,073 nonclinical and 511 clinically referred children and adolescents from The Netherlands and Belgium were included. Results showed that CDI scores were significantly related to DSM-oriented symptoms of both depression and anxiety. CDI scores correlated highly with depression symptoms and moderately with anxiety symptoms. Norms for the CDI were determined by means of multiple regression analysis and depended on sex, age, and country. CDI cutoff scores for selecting individuals at risk for depression and anxiety as measured by the DSM-oriented depression and anxiety scales of the Youth Self Report were determined by means of multiple regression analysis and receiver operating characteristic analysis. A CDI score of 16 was found to have the most optimal balance between sensitivity and specificity for depression, whereas a score of 21 provided the best sensitivity and specificity for anxiety in a subsample of children. We conclude that the CDI is an effective instrument for screening depression and to a lesser extent anxiety in primary and secondary care centers, before applying further assessment of high-risk individuals.  相似文献   
284.
285.
286.
Les families de fumeurs ont étéétudiées à partir du comportement tabagique d'un grand échantillon représentatif des lycéens des 8* et 10* niveaux du centre de la Floride ( n = 1416). Des analyses multivariées ont révélé que le tabagisme de la mère, du père, de la soeur ou du frère aînés rendait compte de 12% de la variance de la décision de se mettre à fumer. Des analyses de régression multiple ont montré qu'une grande soeur fumeuse expliquait la plus grande part de la variance des fumeurs, suivie par la mère et par le père. L'influence du frère aîné n'est pas significative. La famille n'est pas significativement liée au maintien du tabagisme chez les lycéens.
Family smoking habits were examined as they related to the behaviour of a broad, representative sample of eighth and tenth grade students from central and south-central Florida ( n =1416). Multivariate analyses of variance revealed that 12% of the variance for smoking initiation (smoker) was accounted for by the smoking habits of mother, father, older sister, and older brother. Multiple regression analyses showed that older sister's smoking accounted for the greatest independent proportion of smoker variance, followed by mother's and father's smoking. Older brother's smoking habits did not contribute significant unique variance. Family smoking habits were not significantly related to the maintenance of students' smoking behaviour.  相似文献   
287.
288.
289.
Defeasible reasoning is concerned with the logics of non-deductive argument. As is described in the literature, the study of this type of reasoning is considerably more involved than the study of deductive argument, even so that, in realistic applications, there is often a lack of resources to perform an exhaustive analysis. It follows that, in a theory of defeasible reasoning, the order and direction in which arguments are developed, i.e. theprocedure, is important. The aim of this article is to show that debate is the most efficient procedure to argue in the presence of limited resources. To do so, there is first some general theory on defeasible argumentation, which is followed by an introduction to the problem of dialectical search. The problem of dialectical search is (or at least, should be) the essential issue in every theory on argumentation, and emerges at every occasion that involves adjudication on competing arguments. Starting with an example, it is explained that dialectical search can be best scheduled according to classical debating techniques, that work along well-tried methods. These methods (which include various forms of curtailment, interruption, and interpretation) have proven their value in keeping debating efforts within reasonable bounds. How they apply in a theory of formal argument, will be shown in this article.This research was made possible by SION, and is financed by NWO under contract number 612-316-019. Part of this research has been conducted at the Vrije Universiteit Amsterdam. This article contains fragments of Chapter 6 and Chapter 7 of the author's dissertation. Studies in Defeasible Argumentation (1993).  相似文献   
290.
In this paper, experiments are described in which brightness constancy was studied in a Ganzfeld environment. Luminance variation by means of neutral density filters was applied to stimuli consisting of a Ganzfeld with superimposed disks. To this end, a special-purpose apparatus was constructed. Sequential dichoptical brightness matches with a reference stimulus were carried out for the disks as well as the homogeneous surround. The results of these measurements indicate that (1) besides a clear tendency toward brightness constancy, small but systematic effects of the average luminance level are present and (2) the brightness of the Ganzfeld is hardly affected by the presence of the disks. Finally, it is shown that the experimental results can be modeled adequately in terms of a concept that involves an accumulation of contrast information.  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