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   52446篇
  免费   1334篇
  国内免费   17篇
  2020年   401篇
  2019年   493篇
  2018年   3998篇
  2017年   3331篇
  2016年   2894篇
  2015年   728篇
  2014年   730篇
  2013年   3047篇
  2012年   1673篇
  2011年   3429篇
  2010年   3164篇
  2009年   2148篇
  2008年   2642篇
  2007年   3125篇
  2006年   945篇
  2005年   1046篇
  2004年   1009篇
  2003年   906篇
  2002年   876篇
  2001年   939篇
  2000年   934篇
  1999年   724篇
  1998年   416篇
  1997年   359篇
  1996年   330篇
  1995年   341篇
  1994年   319篇
  1993年   303篇
  1992年   562篇
  1991年   549篇
  1990年   533篇
  1989年   499篇
  1988年   520篇
  1987年   477篇
  1986年   467篇
  1985年   486篇
  1984年   419篇
  1983年   366篇
  1982年   311篇
  1981年   315篇
  1979年   447篇
  1978年   357篇
  1977年   298篇
  1975年   341篇
  1974年   430篇
  1973年   421篇
  1972年   320篇
  1971年   316篇
  1968年   366篇
  1967年   317篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
871.
This study replicated the results of an earlier one in which college women showing psychological similarities to anorexics indicated an unrealistically larger body-image relative to controls but only if they were relatively thin. This kind of perceptual enhancement was not found when inanimate objects were rated. The proposal that an enhanced body image plays a dynamic role in motivating food restraint (and may increase the risk of becoming anorexic) was supported by an analysis of dieting strategies.  相似文献   
872.
The present study investigated the congruence between the factor structures of the learning environment and cognitive variables for mathematics and English courses in Grade 10. Three common factors were obtained in each course. Procedural characteristics and cognitive factors in mathematics were highly similar to the corresponding factors in English. However, the formative characteristics factor identified in mathematics was not congruent to the corresponding factor in English. Learning environment variables produced two factors. These factors resembled the congruent factor properties for the two courses when the learning environment and cognitive variables were factor analyzed together. Implications for learning and instructional research are mentioned.  相似文献   
873.
The Slade model for development of anorexia nervosa proposes that the female may seek success and control in her life by pursuing a thin body through dieting when faced with serious personal problems. Extending upon this model, the present program of research has sought to identify those characteristics of women generally at-risk for anorexia nervosa that would make dieting behavior especially successful, permitting the progression from food restraint into food aversion. The present studies considered whether heightened and stress-related inner stimulation could interfere with the at-risk woman's sensitivity to hunger sensations, thereby decreasing her motivation to eat. A series of analyses conducted within two studies indicated: (1) a relationship between elevated daily stress, concern over being over-whelmed by inner feelings, and a loss of discrimination regarding sources of inner feelings, (2) a tendency to narrow attentional focus when overloaded with excessive internal stimulation, and (3) diminished sensitivity to hunger sensations for women generally at-risk for anorexia nervosa given a narrowed attentional focus.  相似文献   
874.
B Küppers 《Psyche》1990,44(4):343-355
The author is an internist in a non-university hospital. He discusses the possibilities and limits of dealing with patients suffering from ulcerative colitis and Crohn's disease. He demonstrates the clinical importance of a psychoanalytic perspective with three case illustrations.  相似文献   
875.
876.
877.
This paper is a detailed critical study of Adolf Grünbaum's work on the Duhemian thesis. I show that (a) Grünbaum's geometrical counterexample to the (D1) subthesis is unsuccessful, even with minimal claims made for what the counterexample is supposed to show, and (b) the (D2) subthesis is not a reasonable one (and cannot correctly be attributed to Duhem). The paper concludes with an argument about the relation between the Duhemian thesis, concerning component hypotheses of a scientific theory, and the view that it is impossible to falsify entire theories conclusively.  相似文献   
878.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
879.
In this paper, we offer a Piagetian perspective on the construction of the logico-mathematical schemas which embody our knowledge of logic and mathematics. Logico-mathematical entities are tied to the subject's activities, yet are so constructed by reflective abstraction that they result from sensorimotor experience only via the construction of intermediate schemas of increasing abstraction. The ‘axiom set’ does not exhaust the cognitive structure (schema network) which the mathematician thus acquires. We thus view ‘truth’ not as something to be defined within the closed ‘world’ of a formal system but rather in terms of the schema network within which the formal system is embedded. We differ from Piaget in that we see mathematical knowledge as based on social processes of mutual verification which provide an external drive to any ‘necessary dynamic’ of reflective abstraction within the individual. From this perspective, we argue that axiom schemas tied to a preferred interpretation may provide a necessary intermediate stage of reflective abstraction en route to acquisition of the ability to use formal systems in abstracto.  相似文献   
880.
Converging operations on a basic level in event taxonomies   总被引:1,自引:0,他引:1  
Research on object concepts has identified one level of abstraction as "basic" in cognition and communication. We investigated whether concepts for routine social events have a basic level by replicating the converging operations used to investigate object concepts. In Experiment 1, subjects were presented with event names from a taxonomy and were asked to list the actions comprising the event. Many more actions were listed at the middle than at the highest taxonomic level, without a further increase at the most specific level, paralleling the pattern of superordinate-, basic-, and subordinate-level object concepts. From these action lists, brief stories were composed for each event. In Experiment 2, subjects made pairwise similarity judgments on the stories. The mean similarity of events increased with specificity, as expected. But differentiation of categories (within-category similarity compared to between-category similarity) was highest for super-ordinates, contrary to results with object categories. In Experiment 3, subjects were fastest in recognizing actions as belonging to events named at the basic level. In Experiment 4, subjects predominantly chose basic-level terms to name stories. We conclude that event taxonomies do show basic-level structure, albeit a less sharply defined and less stable structure than in object taxonomies. The benefits and hazards of extending models of object concepts to other entities, such as social events, are discussed.  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