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   17618篇
  免费   1472篇
  国内免费   1159篇
  2023年   218篇
  2022年   205篇
  2021年   300篇
  2020年   538篇
  2019年   626篇
  2018年   592篇
  2017年   703篇
  2016年   690篇
  2015年   450篇
  2014年   562篇
  2013年   1888篇
  2012年   389篇
  2011年   486篇
  2010年   426篇
  2009年   615篇
  2008年   801篇
  2007年   877篇
  2006年   821篇
  2005年   714篇
  2004年   606篇
  2003年   508篇
  2002年   459篇
  2001年   282篇
  2000年   266篇
  1999年   226篇
  1998年   179篇
  1997年   154篇
  1996年   123篇
  1995年   111篇
  1994年   102篇
  1993年   85篇
  1992年   63篇
  1991年   49篇
  1990年   49篇
  1989年   29篇
  1988年   40篇
  1987年   27篇
  1985年   390篇
  1984年   443篇
  1983年   354篇
  1982年   455篇
  1981年   447篇
  1980年   449篇
  1979年   396篇
  1978年   460篇
  1977年   365篇
  1976年   373篇
  1975年   286篇
  1974年   282篇
  1973年   244篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
Retardate use of retention strategies and the independence of color and form retention were compared with predictions of the Attention-Retention theory of retardate discrimination learning. Lists of two-choice discrimination problems were increased in length from one to capacity, which was defined through criterion retention across a 20-sec interval. It was demonstrated that (a) capacity and rate of adjustment of retentional strategy were directly related to intelligence, (b) at capacity limits the retention of problems in one dimension interfered with retention in a second dimension, and (c) results consistent with a capacity allocation strategy were obtained. The results were interpreted as reflecting short-term memory capacity constraints on the use of rehearsal.  相似文献   
932.
Human infants' discrimination of changes in internal and external elements of compound visual patterns was investigated in four experiments employing a familiarization-novelty paradigm in which visual reinforcing patterns were presented contingent upon rate of high-amplitude nonnutritive sucking. In Experiment 1, 4-month infants discriminated changes in the shape of internal, external and both internal and external figures. One-month infants discriminated external changes in both internal and external figures, but failed to show reliable response recovery when only internal figures were changed. Experiments 2 and 3 failed to explain the 1-month results on the basis of poor resolution of internal figures by showing comparable discrimination of small and large singly-presented figures and by failing to find improved internal discrimination with large separation between internal and external figures. In Experiment 4, 1-month infants showed response recovery to figure additions made adjacent to the initial figure, but not to internal additions. The results are interpreted in terms of attentiveness by young infants to external pattern elements and may indicate early processing of figure-ground information. The developmental differences observed suggest an increased breadth of attention to pattern elements.  相似文献   
933.
To assess the development of monocular slant perception as well as the relative effectiveness of different sources of information, children in first, third, and fifth grades and college adults were asked to make judgments of surface slant on the basis of monocular texture gradient information. Accuracy of judgment increased with increasing age. In addition, differences in gradient effectiveness were found. Compression gradients were relatively ineffective sources of information, whereas perspective and multiple gradients resulted in greater accuracy. The results suggest limitations on the specificity of certain forms of gradients.  相似文献   
934.
A total of 400 children at ages 5, 9, and 12 years were given a component selection task with stimuli differing in color and shape. Relative salience of these two stimulus components was manipulated across subjects in two ways: the standard shapes and colors from previous studies were compared with standard shapes in fluorescent colors, and the latter materials were compared with nonsense shapes in fluorescent colors. While fluorescence of color had little effect, the replacement of standard shapes with nonsense figures caused attention to be redirected from shape to color as the primary cue for learning. This effect was more pronounced at age 9 than at age 5. Apparently there is a greater tendency for older than for younger children to withdraw attention from a normally dominant component such as shape, when it is advantageous to adopt another feature such as color as the primary functional cue. An additional variable was integration of components (color within shape vs color as background for shape). Integration produced generally greater attention to color but did not affect the general pattern of salience effects.  相似文献   
935.
Off-task behavior, correct answering, and participation during beginning reading instruction were recorded for two low-achieving first-grade children during two different rates of teacher presentation. A slow-rate presentation (A) was compared with a fast-rate presentation (B) in an ABABAB design. In slow-rate presentation, there was a delay between the children's response and introduction of the next task. In fast-rate presentation, there was no delay. A new teacher taught during the final AB phases, which allowed for a brief replication. Both teachers were reminded on a fixed-interval 90-sec schedule throughout all phases of the experiment to praise the subjects, thus preventing a confounding of social praise and rate of teacher presentation. Fast-rate presentation was accompanied by a lower per cent occurrence of off-task behavior for both Subjects 1 and 2. For Subject 1, correct answering and participation were more frequent during all three fast-rate phases. For Subject 2, correct answering and participation were more frequent during the fast-rate phases after the first reversal.  相似文献   
936.
The Fishbein regression model (B ≈ BI ≈ (Aact)w0 + (NBs)w1) is designed to predict behavior (B) from attitudes (Aact) and normative beliefs (NBs). Using a variation of theAjzen and Fishbein (Journal of Experimental Social Psychology, 1970,6, 466–487) method, potential limitations of the model were investigated. It was found that certain situational factors were capable of altering the nature of the model significantly. Aact carried a nonsignificant regression weight when the participant had had no prior direct experience with the act and carried a significant weight when the participant had had experience with the act. NB carried a nonsignificant weight under competitive motivational set conditions and a significant weight under cooperative set conditions. These findings raise the question of the generality of the Fishbein model, since different prediction models were required by different situational conditions. The hypothesized association between attitude and behavior appears to be dependent on prior experience with the behavior, while the association between norms and behavior seems to be dependent on consistency between personal motivation and perceived social expectations.  相似文献   
937.
938.
939.
To investigate the development of verbal rehearsal strategies and selective attention in learning disabled children, Hagen's Central-Incidental task was administered to younger learning disabled (M CA = 8.68 years) and normal (M CA = 8.62 years) boys in Experiment 1 and to intermediate (M CA = 10.18 years) and older (M CA = 13.48 years) learning disabled boys in Experiment 2. Also, in Experiment 2, an experimentally induced verbal rehearsal condition was included to determine its effects on serial recall and selective attention performance. In Experiment 1, the serial postion curve of the normals revealed both a primacy and a recency effect, whereas that of the learning disabled revealed a recency effect only. In Experiment 2, both the intermediate and the older learning disabled exhibited both primacy and recency effects under both standard and rehearsal conditions. A developmental analysis of central recall for the three learning disabled groups revealed constant age-related increases in overall central recall and in primacy recall. That the normals recalled more central, but not more incidental, information than the learning disabled in Experiment 1 suggests that the learning disabled are deficient in selective attention. Correlational findings suggest that the selective attention of the learning disabled improves with age. The results were interpreted as support for the hypothesis of a developmental lag in the learning disabled population.  相似文献   
940.
Methods of increasing learning efficiency through a blocking technique were examined in young children. An experimental group of children was trained on an initial task with one relevant dimension, followed by redundancy training in which an incidental dimension also became relevant. A control group given only redundancy training was compared to this group to test how much the experimental subjects blocked or screened out the incidental dimension. In order to increase blocking, three methods were used: a preset transfer problem, an overtraining on the initial task, and a delay following training. The most important finding was increased blocking through the Preset Condition. Overtraining and Delay Conditions had no effect. In addition, more slow learners on the initial task learned about the incidental dimension than fast or intermediate learners. Also, fewer subjects given form on the initial task learned about the incidental dimension than those given color. The Combined Blocking, Delay, and Overtraining group showed partial blocking, while the Preset group demonstrated complete blocking. No developmental differences occurred. The results were interpreted using a modification of Trabasso and Bower's attention model (Attention in learning: Theory and research. New York: Wiley, 1968).  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