全文获取类型
收费全文 | 34237篇 |
免费 | 1521篇 |
国内免费 | 26篇 |
专业分类
35784篇 |
出版年
2020年 | 403篇 |
2019年 | 516篇 |
2018年 | 747篇 |
2017年 | 723篇 |
2016年 | 797篇 |
2015年 | 532篇 |
2014年 | 642篇 |
2013年 | 2780篇 |
2012年 | 1208篇 |
2011年 | 1206篇 |
2010年 | 693篇 |
2009年 | 782篇 |
2008年 | 1042篇 |
2007年 | 1044篇 |
2006年 | 898篇 |
2005年 | 790篇 |
2004年 | 781篇 |
2003年 | 722篇 |
2002年 | 726篇 |
2001年 | 1085篇 |
2000年 | 1089篇 |
1999年 | 807篇 |
1998年 | 363篇 |
1997年 | 331篇 |
1996年 | 319篇 |
1995年 | 335篇 |
1992年 | 635篇 |
1991年 | 592篇 |
1990年 | 571篇 |
1989年 | 547篇 |
1988年 | 539篇 |
1987年 | 485篇 |
1986年 | 484篇 |
1985年 | 535篇 |
1984年 | 438篇 |
1983年 | 404篇 |
1982年 | 312篇 |
1979年 | 476篇 |
1978年 | 330篇 |
1976年 | 319篇 |
1975年 | 361篇 |
1974年 | 434篇 |
1973年 | 461篇 |
1972年 | 399篇 |
1971年 | 342篇 |
1970年 | 317篇 |
1969年 | 334篇 |
1968年 | 416篇 |
1967年 | 370篇 |
1966年 | 357篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
G. C. Preston A. Dickinson N. J. Mackintosh 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1986,38(2):217-237
Three experiments used a discriminated operant procedure to study conditional discrimination learning in rats. The first experiment showed that rats were capable of learning a biconditional discrimination in which two contexts served as conditional cues signalling the reinforcement contingencies associated with two discriminative stimuli. The discrimination was learned equally well when one discriminative stimulus signalled food, the other its absence, and when one stimulus signalled food, the other extinction plus mild footshock.
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
62.
This research reports a first attempt to study adaptation to laterally displacing prisms in human infants of ages six to ten months. Twenty infants were tested over four days under conditions similar to those used in adult adaptation studies. Evidence was found of vigorous adaptation when infants were exposed to base-right prisms under conditions of active exposure. Detailed consideration is given to the conditions and methods of studying adaptation in infants and implications for adult studies. 相似文献
63.
64.
65.
66.
A high proportion of positive responses was obtained from students who participated in three different types of pre-college orientation programs. Small group approaches consistently elicited more favorable responses than assemblies or large groups. Greater faculty involvement resulted in participants' noting an increased academic emphasis. Participants believed they had benefited in some way from programs which varied considerably as to length, activities, organization, and purposes. 相似文献
67.
68.
69.
70.
Although message‐production theories often assume that goals behave dynamically to direct communication behavior, few studies consider the interconnectedness of goals and behavior throughout interactions. Here, the interrelationship of communication goals and tactics was examined through a sequential analysis of 47 conflict interactions between close friends or dating partners. It was posited that for both the initiators and resistors in a conflict, the importance of relational or other‐identity goals would be associated with the use of integrative tactics and the importance of instrumental or self‐identity goals would be related to the use of distributive tactics. We examined these predictions within and across partners. Analyses indicated that for both conflict initiators and resistors, the importance of a combination self/instrumental goal predicted the use of distributive tactics and the importance of an other‐identity goal lead to partner‐oriented tactics. For resistors, the importance of an instrumental goal was associated with the use of distributive tactics and the importance of a combination identity/relational goal was aligned with issue‐oriented tactics as well. Across partners, several significant patterns between one partner’s use of distributive or integrative tactics and the other partner’s goals were observed. Implications of the results for understanding conflict and message production are discussed. 相似文献