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   23198篇
  免费   139篇
  2023年   21篇
  2022年   19篇
  2021年   44篇
  2020年   48篇
  2019年   67篇
  2018年   3547篇
  2017年   2873篇
  2016年   2331篇
  2015年   267篇
  2014年   148篇
  2013年   458篇
  2012年   692篇
  2011年   2500篇
  2010年   2590篇
  2009年   1534篇
  2008年   1821篇
  2007年   2261篇
  2006年   129篇
  2005年   326篇
  2004年   238篇
  2003年   197篇
  2002年   154篇
  2001年   62篇
  2000年   90篇
  1999年   46篇
  1998年   61篇
  1997年   52篇
  1996年   36篇
  1995年   24篇
  1994年   36篇
  1993年   26篇
  1992年   30篇
  1991年   22篇
  1990年   32篇
  1989年   26篇
  1988年   24篇
  1987年   22篇
  1986年   23篇
  1985年   28篇
  1984年   29篇
  1983年   24篇
  1982年   34篇
  1981年   30篇
  1980年   27篇
  1979年   30篇
  1978年   20篇
  1977年   20篇
  1976年   19篇
  1975年   19篇
  1973年   15篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
The use of rats as discriminative stimuli   总被引:1,自引:1,他引:0       下载免费PDF全文
A FREE OPERANT PROCEDURE WAS USED TO DETERMINE WHETHER OR NOT ONE RAT COULD DISCRIMINATE: (1) between the presence and absence of a second rat, and (2) between two other rats of the same species and sex. The subjects were four male Wistar rats. The discriminatory response was a bar press and food was used as reinforcement during training. Although there were wide individual differences in rate of learning, all subjects learned to make both discriminations.  相似文献   
62.
This paper presents the results from an investigation of the true probability distributions of the range of rank totals. A procedure for generating an approximation to the true distributions is also given. A comparison of the results of this approximation with an extensive criterion of generated true and sample distributions, and with other approximations is indicated. Accurate estimates of the critical ranges necessary to reach significance at three commonly used alpha levels, where the number of judges and items is less than or equal to sixteen, are presented in tabular form.  相似文献   
63.
The debate regarding the unitary versus multiple nature of the human person is examined with special attention to the division between conscious and unconscious. The roots of the unconscious are traced to the experience of alienation or feeling divided within. An existential analysis is provided in order to shed light on the nature of the unconscious. The experience of feeling divided within is explained as a metaphor that is taken literally. An existential-phenomenological explanation of the unconscious is provided which preserves the essential unity of the human person.  相似文献   
64.
The contents of 800 singles ads were examined. They were compared by the gender of the advertiser, the year of appearance (1991 and 1986), and the SES of the target readership (affluent and general). There were very few advertisers who listed themselves as black, so these ads were not included in the study. Gender differences were most important. Men were more likely to offer financial security and seek attractiveness. Women were more likely to offer attractiveness and seek financial security. The gender differences were in agreement with those reported for over a decade and from many geographical areas, although less than half of the advertisers mentioned either finances or attractiveness. Contrary to our hypotheses, the contents of mens' and womens' ads were more different in 1991 than they had been in 1986 and more in conformity with sexual stereotypes. Ads in a paper with an affluent readership were more likely to mention educational and financial status while ads in a paper with a readership throughout the metropolitan area were more likely to mention physical characteristics.  相似文献   
65.
This study investigated the effectiveness of using visual cues to highlight the seams of baseballs to improve the hitting of curveballs. Five undergraduate varsity baseball team candidates served as subjects. Behavior change was assessed through an alternating treatments design involving unmarked balls and two treatment conditions that included baseballs with 1/4-in. and 1/8-in. orange stripes marking the seams of the baseballs. Results indicated that subjects hit a greater percentage of marked than unmarked balls. These results suggest that the addition of visual cues may be a significant and beneficial technique to enhance hitting performance. Further research is suggested regarding the training procedures, effect of feedback, rate of fading cues, generalization to live pitching, and generalization to other types of pitches.  相似文献   
66.
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   
67.
The present study used a multitrait-multimethod technique [D.T. Campbell and D. W. Fiske (1959) “Convergent and Discriminant Validation by the Multitrait-Multimethod Matrix,” Psychological Bulletin, 56, 81–105] to examine Bem's [(1974) “The Measurement of Psychological Androgyny,” Journal of Consulting and Clinical Psychology, 42, 152–162] use of an instrumental-expressive dichotomy to conceptualize the Masculinity and Femininity scales of the Bem Sex Role Inventory as statistically orthogonal constructs. Results indicate that while perhaps reliable, masculinity and femininity lack clear convergent and discriminant validity. Therefore, Bem's contention that masculinity and femininity are orthogonal constructs is questioned. Results are discussed in light of trait- vs. method-driven research.  相似文献   
68.
State Medicaid programs are rapidly converting fee-for-service health delivery systems to managed care for people with disabilities. In theory, managed care models of health delivery will substantially improve the quality of care for people with disabilities, but in reality, few successful models exist. This period of transition holds both opportunities and challenges for psychologists in medical settings. Because Medicaid reforms for people with disabilities may herald similar reforms for both the public and the private sectors, psychology's response will determine its role in the future of health care delivery for this population. Changes in training and increased attention to outcomes research, innovations in practice, and advocacy will be the keys to success.  相似文献   
69.
Proponents of the projection strategy take an epistemic rule for the evaluation of English conditionals, the Ramsey test, as clue to the truth-conditional semantics of conditionals. They also construe English conditionals as stronger than the material conditional. Given plausible assumptions, however, the Ramsey test induces the semantics of the material conditional. The alleged link between Ramsey test and truth conditions stronger than those of the material conditional can be saved by construing conditionals as ternary, rather than binary, propositional functions with a hidden contextual parameter. But such a ternary construal raises problems of its own.  相似文献   
70.
Wolter  Frank 《Studia Logica》1997,58(2):229-259
This paper investigates partitions of lattices of modal logics based on superintuitionistic logics which are defined by forming, for each superintuitionistic logic L and classical modal logic , the set L[] of L-companions of . Here L[] consists of those modal logics whose non-modal fragments coincide with L and which axiomatize if the law of excluded middle p V p is added. Questions addressed are, for instance, whether there exist logics with the disjunction property in L[], whether L[] contains a smallest element, and whether L[] contains lower covers of . Positive solutions as concerns the last question show that there are (uncountably many) superclean modal logics based on intuitionistic logic in the sense of Vakarelov [28]. Thus a number of problems stated in [28] are solved. As a technical tool the paper develops the splitting technique for lattices of modal logics based on superintuitionistic logics and ap plies duality theory from [34].  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