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   83277篇
  免费   3403篇
  国内免费   38篇
  86718篇
  2020年   834篇
  2019年   1092篇
  2018年   1470篇
  2017年   1476篇
  2016年   1610篇
  2015年   1147篇
  2014年   1364篇
  2013年   6278篇
  2012年   2532篇
  2011年   2680篇
  2010年   1640篇
  2009年   1688篇
  2008年   2325篇
  2007年   2367篇
  2006年   2150篇
  2005年   1908篇
  2004年   1784篇
  2003年   1670篇
  2002年   1782篇
  2001年   2679篇
  2000年   2650篇
  1999年   1994篇
  1998年   939篇
  1997年   848篇
  1996年   838篇
  1995年   796篇
  1993年   772篇
  1992年   1667篇
  1991年   1535篇
  1990年   1519篇
  1989年   1408篇
  1988年   1397篇
  1987年   1312篇
  1986年   1375篇
  1985年   1436篇
  1984年   1201篇
  1983年   1099篇
  1982年   811篇
  1979年   1280篇
  1978年   923篇
  1975年   1026篇
  1974年   1152篇
  1973年   1261篇
  1972年   1081篇
  1971年   987篇
  1970年   886篇
  1969年   925篇
  1968年   1174篇
  1967年   1061篇
  1966年   925篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Public goods theories highlight an incentive system that rewards ‘free riding’ on the contributions of early contributors toward collective actions. However, because such theories focus on creation of the good, they may underestimate returns that accrue to early contributors subsequent to the good's realization. The concept of formative investment is introduced here to describe the extent to which organizations help to create public goods such as interorganizational linkages like participatory federations. Data from the CEOs of 48 organizations involved in a participatory federation were used to assess how an organization's level of formative investment is related to later patterns of dependency and interaction among federation members. Findings suggest that from a long‐term perspective, and for goods that involve communication and interaction, the incentive structure may not be so favorable for free riders. To the extent that organizations with high formative investment have the capability to envision the future and communicate that vision to potential federation partners, they may be able to both reduce free riding and secure for themselves advantageous positions in the subsequent network of relations.  相似文献   
63.
64.
65.
The token economy has been the primary model for the behavioral management of inpatient populations. However, this basically operant approach seldom emphasizes the development of cognitive-coping skills to help patients more effectively manage stressors that result in hospitalization. The Therapeutic Contract Program (TCP) is described as an inpatient-treatment strategy that is designed to help foster such cognitive-coping and self-control skills. While external structure is provided by components of this program, subprograms of the TCP have as their goal the development of internally-attributed coping skills and self-perceptions of competence. This preliminary report describes the structure of the TCP, as well as planned and in-progress measures of program participation and treatment outcome.  相似文献   
66.
67.
On understanding     
WHITELEY CH 《Mind》1949,58(231):339-351
  相似文献   
68.
69.
Three factors that have transformed perceptual research in the last fifty years are the digital computer, single-unit electrophysiology, and molecular biology. Amongst the developments in which members of the Experimental Psychology Society have been central are: the recognition of the role of optic flow in spatial vision; the demonstration that our perceptual systems contain parallel pathways extracting different information from the sensory array; the identification of specific detectors that can be selectively adapted in psychophysical experiments; and the transfer of the concepts of fourier analysis from audition to vision. The history of Opponent Process Theory offers an example where experimental psychologists have been misled by too simple an interpretation of physiological recordings.  相似文献   
70.
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