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   4555篇
  免费   228篇
  国内免费   2篇
  2023年   42篇
  2022年   31篇
  2021年   65篇
  2020年   102篇
  2019年   116篇
  2018年   155篇
  2017年   151篇
  2016年   209篇
  2015年   118篇
  2014年   158篇
  2013年   534篇
  2012年   259篇
  2011年   258篇
  2010年   163篇
  2009年   143篇
  2008年   211篇
  2007年   200篇
  2006年   174篇
  2005年   157篇
  2004年   161篇
  2003年   150篇
  2002年   117篇
  2001年   102篇
  2000年   86篇
  1999年   76篇
  1998年   59篇
  1997年   56篇
  1996年   44篇
  1995年   49篇
  1994年   38篇
  1993年   42篇
  1992年   47篇
  1991年   33篇
  1990年   40篇
  1989年   23篇
  1988年   33篇
  1987年   23篇
  1986年   25篇
  1985年   23篇
  1984年   28篇
  1983年   21篇
  1982年   26篇
  1981年   14篇
  1980年   16篇
  1979年   24篇
  1978年   14篇
  1977年   19篇
  1974年   19篇
  1972年   14篇
  1970年   13篇
排序方式: 共有4785条查询结果,搜索用时 15 毫秒
41.
This research investigated the interplay between mood, disclosure language, and ad skepticism on consumers' recognition and evaluation of native advertising. During two online experiments, participants first received a mood manipulation and then read an article-style native advertisement. Results from both studies indicated that participants were more likely to recognize a native ad with an explicit rather than an implicit disclosure label, and a negative mood was more likely than a positive mood to drive participants to recognize the native ad. More importantly, participants in a positive mood evaluated a native ad with an implicit disclosure more favorably than an ad with an explicit disclosure. By contrast, participants in a negative mood responded more positively to a native ad with explicit disclosure compared to an ad with implicit disclosure. Study 2 demonstrated that the interaction between mood and disclosure language was further moderated by individuals' levels of ad skepticism. These results are believed to provide meaningful theoretical and practical implications to the field of native advertising and consumer behavior.  相似文献   
42.
Raven's Advanced Progressive Matrices (APM) Set I is a validated and brief test of fluid intelligence, ideal for use in busy clinical settings. However, there is a dearth of normative data allowing an accurate interpretation of APM scores. To address this, we present normative data from across the adult lifespan (18–89 years) for the APM Set I. Data are presented in five age cohorts (total N = 352), including two older adult cohorts (65–79 years and 80–89 years), which allows age-standardized assessment. We also present data from a validated measure of premorbid intellectual ability, which was absent from previous standardizations of longer forms of the APM. In line with previous findings, a striking age-related decline was noted, beginning relatively early in adulthood and most marked amongst lower-scoring individuals. Older adults did not demonstrate difficulty with specific test items or make an increased proportion of specific errors. Sex was not a significant predictor of performance. The data set is of particular use in the neuropsychological assessment of older adults, given the known susceptibility of fluid intelligence to both the effects of normal ageing and acquired brain injury in older age. The results are discussed in light of theories of neurological ageing.  相似文献   
43.
Two experiments examined mouse killing as a reinforcer of key pressing by rats that killed mice. In Experiment I, mouse-killing rats performed the key-pressing response when each press was reinforced with presentation of a mouse. Offered a choice between a key that yielded presentation of mice and one that did not, the rats preferred the key that yielded mice. When the contingency was reversed, the rats preferred the other key and continued to kill mice. In Experiment II, mouse-killing rats that did not kill rat pups performed a key-pressing response reinforced with presentation of mice on a variable-interval schedule. In tests for responding reinforced on that schedule with presentation of normal mice, anesthetized mice, dead mice, or rat pups, these rats that killed mice but not rat pups exhibited a decline in response rate when rat pups were the reinforcer. Altering the condition of the mice did not significantly affect performance.  相似文献   
44.
In two experiments, the effect of an illuminated response key on the acquisition of stimulus control by an airflow stimulus was assessed. In the first experiment, pigeons were given nondifferential training with airflow emerging from behind the response key in one of three conditions of illumination: trained to peck a lighted key, trained to peck an unlighted key with a houselight present, trained to peck a key in total darkness. After 10 days of training on a variable-interval schedule of reinforcement, all subjects were given a generalization test on airflow velocity. The gradients for subjects trained in the dark were sharp, while those for subjects trained in lighted conditions were shallow. In the second experiment, the effect of an irrelevant keylight on the acquisition of an airflow velocity discrimination was assessed. Two groups of pigeons were trained to discriminate two airflow velocities. One group was trained with a lighted response key and the other was trained to peck the response key in total darkness. The dark-trained subjects acquired the discrimination more rapidly. The results demonstrate that the acquisition of stimulus control by airflow with either a differential or nondifferential training procedure can be overshadowed by keylight.  相似文献   
45.
46.
47.
48.
49.
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
50.
PIGEONS ARE SENSITIVE TO THE SPATIAL ORGANIZATION OF COMPLEX VISUAL STIMULI   总被引:1,自引:0,他引:1  
Abstract— Two experiments investigated the role of spatial organisation in the discrimination and generalization of complex visual stimuli by pigeons. In Experiment 1, after pigeons had been trained to discriminate line drawings of four objects, they were tested with novel pictures in which the same component parts of the objects were spatially rearranged. The spatially scrambled pictures led to a dramatic drop in recognition accuracy, hut responding remained above chance. In Experiment 2, pigeons reached a high level of discriminative performance when required to choose among four different spatial arrangements of the same object parts. These results confirm Cerella's (1980) conclusion that pigeons discriminate the component parts of complex visual stimuli, but. unless it is assumed that the scrambling deleted or created emergent features, the results disconfirm his conclusion that spatial organization plays no role in pigeons' picture perception.  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