全文获取类型
收费全文 | 21499篇 |
免费 | 76篇 |
出版年
2021年 | 18篇 |
2020年 | 17篇 |
2019年 | 24篇 |
2018年 | 3501篇 |
2017年 | 2834篇 |
2016年 | 2263篇 |
2015年 | 211篇 |
2014年 | 103篇 |
2013年 | 168篇 |
2012年 | 621篇 |
2011年 | 2424篇 |
2010年 | 2536篇 |
2009年 | 1493篇 |
2008年 | 1722篇 |
2007年 | 2206篇 |
2006年 | 73篇 |
2005年 | 256篇 |
2004年 | 200篇 |
2003年 | 141篇 |
2002年 | 100篇 |
2001年 | 49篇 |
2000年 | 68篇 |
1999年 | 29篇 |
1998年 | 40篇 |
1997年 | 30篇 |
1996年 | 14篇 |
1995年 | 10篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 21篇 |
1991年 | 14篇 |
1990年 | 22篇 |
1989年 | 14篇 |
1988年 | 12篇 |
1987年 | 23篇 |
1986年 | 18篇 |
1985年 | 19篇 |
1984年 | 9篇 |
1983年 | 20篇 |
1982年 | 14篇 |
1980年 | 13篇 |
1978年 | 9篇 |
1977年 | 8篇 |
1976年 | 15篇 |
1975年 | 11篇 |
1974年 | 14篇 |
1973年 | 8篇 |
1972年 | 10篇 |
1971年 | 15篇 |
1968年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
81.
82.
Stanley J. Weiss 《Learning and motivation》1976,7(4):477-516
The associations formed in the components of a multiple schedule can be classified as (1) stimulus-response (S-R) associations and (2) stimulus-reinforcer (S-SR) associations. The present experiments sought to determine the individual contribution of these S-R and S-SR associations to stimulus control by manipulating them independently. Responses postponed shocks by 25 sec in the presence of a tone alone and a light alone in all experiments. The contingencies programmed in the absence of both tone and light established a reference for the S-R and S-SR associations in tone and in light. All four possible combinations of signalling response increase or decrease together with incentive increase or decrease were studied. Although the influence of the contingencies operating in the absence of tone and light was difficult to detect from response rates in tone or light, presenting tone and light together revealed clear effects. Response rates in tone and light together relative to those in either alone depended upon the contingency operating in the absence of tone and light. Stimulus-response and stimulus-reinforcer associations appeared to counteract each other when in opposition and combine together to enhance each other when in agreement. This suggested that the associations of a stimulus to response and to incentive combine algebraically in determining stimulus control. An algebraic analysis in terms of the S-R and S-SR associations conditioned to the stimulus elements comprising the training and test stimuli accounted for the observed patterns of data. 相似文献
83.
A group of 16 children from a normal community population was compared with two groups of 16 children referred for clinical evaluation of hyperactivity. These three groups were matched on age, sex, and race. One of the clinic groups was matched with the community sample on IQ and social class as well, while the children in the other clinic group were mentally retarded and of somewhat lower social class. All children were observed in a standardized playroom for two 15-minute sessions, one under free play instructions and the other under instructions restricting activity and toy-changing behavior. The two groups of children referred for evaluation of hyperactivity had significantly higher playroom activity scores than controls under both instructional conditions and significantly higher toy-change scores under restrictive instructions. Parental ratings of activity were also significantly higher in both clinic groups than in the community group. The mentally retarded clinic sample did not differ from the other clinic sample on any of the measures of activity or toy switching.A preliminary version of this article was presented at the meeting of the American Psychological Association, Chicago, Illinois, August 30, 1975, as part of a Symposium on Hyperactive Children: Assessment, Treatment, and Outcome. This research was supported by U. S. Public Health Service, Maternal and Child Health Project No. 916 and by Grants HD-03110 and ES-01104. 相似文献
84.
A software system for the administration of six different strategies of adaptive ability tests in a variety of formats was developed both on a large-scale time-sharing system and on a real-time minicomputer system. Factors influencing both hardware selection and software design are discussed. 相似文献
85.
86.
87.
88.
89.
90.