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   55970篇
  免费   1326篇
  国内免费   11篇
  2018年   3896篇
  2017年   3189篇
  2016年   2734篇
  2015年   603篇
  2014年   574篇
  2013年   3487篇
  2012年   1406篇
  2011年   3218篇
  2010年   3012篇
  2009年   1983篇
  2008年   2506篇
  2007年   2884篇
  2006年   741篇
  2005年   815篇
  2004年   749篇
  2003年   719篇
  2002年   651篇
  2001年   1195篇
  2000年   1177篇
  1999年   870篇
  1998年   396篇
  1996年   501篇
  1995年   471篇
  1994年   464篇
  1993年   432篇
  1992年   897篇
  1991年   800篇
  1990年   808篇
  1989年   706篇
  1988年   711篇
  1987年   690篇
  1986年   692篇
  1985年   674篇
  1984年   600篇
  1983年   499篇
  1982年   390篇
  1981年   406篇
  1979年   566篇
  1978年   427篇
  1976年   387篇
  1975年   528篇
  1974年   518篇
  1973年   583篇
  1972年   558篇
  1971年   496篇
  1970年   442篇
  1969年   426篇
  1968年   536篇
  1967年   454篇
  1966年   441篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
971.
Errors in a serial choice-reaction time experiment employing two-finger chord responses to alphabetic stimuli are shown to be distributed in a significantly non-random fashion. Two factors are postulated which are relevant to prediction of the error response. These are the presence or absence of a common finger, and the difference in finger separation, between the actual and the required response. It is suggested that the chord response is coded in terms of a pattern (the distance between the two response components). Responses which mirror the correct response about the centre of the hand are also shown to be significantly more frequent.  相似文献   
972.
In behavior studies of genetically timid and normal dogs it was possible to focus on nervous non-performing animals in a search for agents which might attenuate the overriding anxiety which causes these animals to become rigid, aversive-avoiding or bizarre in the presence of humans. Of the drugs tested, chlordiazepoxide (Librium, Roche), 75 to 200 mg per dog per day, was most effective in alleviating the anxious condition. Sometimes the drug had the effect of getting the animal over a “threshold” so that he continued to perform (bar-pressing) indefinitely after once started through the aid of chlordiazepoxide. This is considered an example of both schizokinesis and autokinesis which Gantt first described and associated with drug action utilizing conditional response techniques.  相似文献   
973.
974.
975.
Constraint redundancy (Rc) was varied in order to manipulate the statistical structure of sets of patterns. Measures of pattern features and Rc were related to the categorization by Ss who had experienced different types of preexposure to sets of patterns from the same stimulus domain. Both Rc and pattern measures were related to the categories produced by Ss in a schematic-concept-formation (SCF) task.  相似文献   
976.
977.
978.
979.
980.
A Systems Dilemma   总被引:1,自引:0,他引:1  
The current shift of interest, reflected in public policy, from the production of goods to the provision of services, has caused a major re-examination of the nature of the services the individual can expect from his society. This re-examination is producing a number of insights, some of them shocking. In particular, we are learning that many of the systems we have created to deliver services are, in the name of “progress” and “civilization,” contributing to the conditions of human distress they were designed to alleviate. Much has been written lately about how service systems of one kind or another subvert their announced goals—how a welfare system perpetuates poverty, or how the medical profession creates iatrogenic illness. There has not been very much written, however, about how several systems inadvertently combine in their day to day operations in such a way as to frustrate each others' activities, and how, in so doing, they destroy in varying degrees the lives of people, or render it difficult for them to improve their lives. We have all been much too tightly locked in our own niches by training, experience, and various types of private interest to see this kind of interlock. It comes into sharp perspective only when one studies the problems of a single person in terms of his total life space, his “ecology.” This paper represents an effort to describe one such situation in a family as viewed from a community health services program designed to approach human crises as ecological phenomena, and to explore and respond to them within this framework. We have found that the best way to organize our view of the environmental field people move in is according to the diverse systems which make it up, so we have labeled our theoretical base “ecological systems theory.” ( 1 ) What is of particular interest to the behavioral scientist in the situation described is that neither individual nor family diagnosis, nor the contributions of the larger systems (in this case a housing system and a system of medical care) will, if viewed separately, explain the state of the man in question. Only when the contributions of all of these systems are made clear, and their interrelationships explored, do the origins of the phenomena described begin to emerge.  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