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   5753篇
  免费   1115篇
  国内免费   32篇
  6900篇
  2019年   71篇
  2018年   94篇
  2017年   91篇
  2016年   109篇
  2015年   87篇
  2014年   96篇
  2013年   506篇
  2012年   188篇
  2011年   215篇
  2010年   225篇
  2009年   286篇
  2008年   237篇
  2007年   269篇
  2006年   205篇
  2005年   184篇
  2004年   206篇
  2003年   218篇
  2002年   193篇
  2001年   188篇
  2000年   94篇
  1999年   151篇
  1998年   137篇
  1997年   102篇
  1996年   148篇
  1995年   107篇
  1994年   117篇
  1993年   112篇
  1992年   141篇
  1991年   131篇
  1990年   127篇
  1989年   112篇
  1988年   93篇
  1987年   80篇
  1986年   80篇
  1985年   73篇
  1984年   86篇
  1983年   49篇
  1982年   91篇
  1981年   69篇
  1980年   57篇
  1979年   62篇
  1976年   51篇
  1973年   49篇
  1972年   54篇
  1971年   50篇
  1968年   65篇
  1966年   53篇
  1964年   80篇
  1963年   73篇
  1962年   48篇
排序方式: 共有6900条查询结果,搜索用时 0 毫秒
971.
972.
973.
The performance of a rat provided with continuous opportunity to obtain reinforcing brain stimulation over a 20-day period is described in detail. The animal averaged 29.2 responses per min during the entire time. Testing session was terminated by experimenters, but a day-by-day analysis of behavior provided no evidence that the animal would have stopped responding.  相似文献   
974.
初级指挥官人格类型与PM领导行为类型有效性的关系   总被引:5,自引:0,他引:5  
通过对陆军初级指挥官人格心理类型与领导行为有效性的心理学研究 ,探讨个人的领导潜能、人格心理类型对领导行为有效性的影响。研究发现 :1方差分析表明 ,具有不同领导行为的指挥官在人格维度上存在明显的统计学差异。提示了指挥官的领导行为取向与人格因素有密切的关系。2卡方分析结果也表明 ,PM型行为的军官在其人格特征上具有“ESTJ”组合特征 ,而 pm型的军官则正好相反 ;另外 ,pm型的军官在成就动机上获得高分的人数最少。3系统聚类分析显示 ,“成就动机”、“感觉”和“判断”三种人格因素与军事指挥官完成整体领导职能有着更为密切的关系。  相似文献   
975.
Effects of d-amphetamine, chlorpromazine, and chlordiazepoxide on lever pressing under direct control of spaced-responding schedules were compared with effects on intercurrent drinking and wheel running in the rat. Drug effects on lever pressing were systematically related to dose and were consistent for all animals; drug effects on intercurrent behavior were generally different for each animal. In the case of lever presses, increasing doses of d-amphetamine first increased and then decreased response rate, increasing doses of chlorpromazine produced graded decreases in response rate, and doses of chlordiazepoxide up to 40 mg/kg produced no effect on response rate. These data are discussed in context with the concept of schedule control, and it is suggested that the behavioral pharmacology of intercurrent behavior be explored as a useful procedure in the experimental analysis of intercurrent behavior.  相似文献   
976.
977.
978.
979.
The effects of pentobarbital and d-amphetamine were assessed on key pecking by pigeons under conventional single-key multiple schedules and under two-key multiple schedules in which discriminative stimuli appeared on one key (stimulus key) while pecks on a second key (constant key) produced food. Pecks on the stimulus key had no scheduled consequences. A 60-second variable-interval schedule operated in one component of each multiple schedule: either extinction or a 60-second variable-time schedule operated in the alternate component. When the alternate-component schedule was extinction, a high rate of responding was maintained in the variable-interval component of the single-key schedule; responding on both keys was maintained in the variable-interval component of the two-key schedule. Pentobarbital increased responding in the variable-interval component of the single-key schedule and increased stimulus-key, but not constant-key responding in that component of the two-key schedule. When the alternate-component schedule was changed to variable time, responding declined in the variable-interval component of the single-key schedule; stimulus-key responding was no longer maintained under the two-key schedule. Pentobarbital decreased responding in the variable-interval component of both schedules. With an exception, d-amphetamine only decreased responding in the variable-interval component of the single- and two-key schedules both when the alternate-component schedule was extinction and when it was variable time. The results suggest that the effects of pentobarbital, but not d-amphetamine, depend on the nature of the contingency (stimulus-reinforcer, response-reinforcer) that maintains responding.  相似文献   
980.
Two pigeons had access to multiple concurrent schedules of reinforcement for 24 hours per day in their home cages. The variable-interval schedules comprising the multiple concurrent schedules were varied across 16 conditions. In three sets of conditions, one schedule was varied while its concurrent alternative and the concurrent schedules in the other component were held constant. Behavioral contrast was observed; that is, as the rate of reinforcement arranged by the varied schedule decreased, response rates on the constant schedules typically increased. These conditions formed part of two larger sets of conditions in which the concurrent schedules in one multiple-schedule component remained constant while the concurrent schedules in the other component were varied. Successive independence was found, in that behavior allocation during the constant component did not vary as a function of the reinforcer ratios in the varied component. Successive independence between components in multiple concurrent schedules is a robust result that occurs in closed economies and under conditions that promote behavioral contrast.  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