全文获取类型
收费全文 | 48129篇 |
免费 | 2020篇 |
国内免费 | 17篇 |
专业分类
50166篇 |
出版年
2020年 | 479篇 |
2019年 | 546篇 |
2018年 | 803篇 |
2017年 | 791篇 |
2016年 | 848篇 |
2015年 | 641篇 |
2014年 | 737篇 |
2013年 | 3328篇 |
2012年 | 1393篇 |
2011年 | 1373篇 |
2010年 | 876篇 |
2009年 | 791篇 |
2008年 | 1205篇 |
2007年 | 1188篇 |
2006年 | 1045篇 |
2005年 | 964篇 |
2004年 | 919篇 |
2003年 | 851篇 |
2002年 | 868篇 |
2001年 | 1599篇 |
2000年 | 1539篇 |
1999年 | 1109篇 |
1998年 | 493篇 |
1996年 | 418篇 |
1992年 | 1029篇 |
1991年 | 962篇 |
1990年 | 981篇 |
1989年 | 876篇 |
1988年 | 878篇 |
1987年 | 825篇 |
1986年 | 847篇 |
1985年 | 920篇 |
1984年 | 725篇 |
1983年 | 651篇 |
1982年 | 469篇 |
1981年 | 433篇 |
1979年 | 809篇 |
1978年 | 509篇 |
1977年 | 497篇 |
1976年 | 489篇 |
1975年 | 701篇 |
1974年 | 803篇 |
1973年 | 860篇 |
1972年 | 742篇 |
1971年 | 692篇 |
1970年 | 675篇 |
1969年 | 674篇 |
1968年 | 881篇 |
1967年 | 759篇 |
1966年 | 700篇 |
排序方式: 共有10000条查询结果,搜索用时 6 毫秒
911.
In two experiments, we assessed the ability of a feedback stimulus during helplessness training to reduce the performance deficits common to inescapable shock. In each experiment, four groups of rats were exposed to either escapable shock (E), inescapable shock with a feedback stimulus following shock termination (Y-FS), inescapable shock with no feedback stimulus (Y-NFS), or no shock (N). The feedback stimulus eliminated the interference effects of inescapable shock when tested with an FR-3 lever press escape task (Experiment 1) or on an FR-1 task with a 3-s delay between the response and shock termination (Experiment 2). These results suggest that stress-induced biochemical changes may mediate the interference effects seen in inescapably shocked rats. 相似文献
912.
Edward J Callen Wallace R McAllister Dorothy E McAllister 《Learning and motivation》1984,15(3):302-320
In two experiments, fear was conditioned to the situational cues in one compartment of a hurdle-jumping apparatus and was then extinguished. Subsequently, either one shock (Experiment 1) or three or nine shocks (Experiment 2) were given in a situation distinctively different from that in which conditioning and extinction had taken place. Although some associative strength between the situational cues and fear was shown to have remained after extinction, in neither experiment did the postextinction-shock treatment increase the fear elicited by these cues: Escape-from-fear performance was no better in the shocked groups than in control groups given no additional shock. Thus, the nonassociative hypothesis which postulates that inflating the value of the representation of the UCS with shock-alone presentations can reinstate the extinguished fear of a stimulus was not supported. Rather, the results showed that, after extinction, an increase in fear of a simulus depended on further conditioning to that stimulus. The data also indicated that the nonvisual components of the situational cues predominated over the visual component. 相似文献
913.
914.
915.
Unlike earlier tests of an oversimplified version of this model, the validity of W. Mobley's (1977, Journal of Applied Psychology, 62, 237-240) original turnover model was fully investigated. Constructs that were neglected in prior studies were assessed and previously examined constructs were operationalized with more reliable measures. Measures of all constructs in Mobley's model were obtained from a survey of 192 hospital employees. Turnover data were collected a year following survey administration. Following the theoretical causal ordering of Mobley's constructs, each construct was regressed on all causally prior constructs. In general, each construct was accurately predicted by the linear combination of predictors representing its causal determinants. In the majority of instances, the best predictor of a model construct was the construct's immediate causal antecedent. Further, an alternative model was evaluated and compared with Mobley's model using path analysis. 相似文献
916.
917.
918.
919.
Sandra R. Brown Ph.D. 《Pastoral Psychology》1984,33(2):136-140
This article acknowledging and celebrating William Barr Oglesby, Jr. as Pastoral Theologian of the Year for 1983, was originally published inPastoral Psychology 32(1) in Fall, 1983. As a result of some errors that inadvertently modified both the tone and the meaning of the text, we are republishing this article here in its entirety. 相似文献
920.
This study indicates that sales volume, stage in the product life cycle, profitability and turnover are all important predictors of the method and magnitude of financial rewards provided by high tech firms to R and D employees. The most favorable situational factors for R and D incentive compensation are a low sales volume high tech company, operating in the growth stage of the product life cycle, with high turnover rates, and capable of linking profitability to incentive rewards such as bonuses. 相似文献