全文获取类型
收费全文 | 4015篇 |
免费 | 126篇 |
专业分类
4141篇 |
出版年
2021年 | 37篇 |
2020年 | 66篇 |
2019年 | 59篇 |
2018年 | 119篇 |
2017年 | 103篇 |
2016年 | 100篇 |
2015年 | 66篇 |
2014年 | 68篇 |
2013年 | 318篇 |
2012年 | 137篇 |
2011年 | 116篇 |
2010年 | 73篇 |
2009年 | 94篇 |
2008年 | 98篇 |
2007年 | 106篇 |
2006年 | 88篇 |
2005年 | 86篇 |
2004年 | 75篇 |
2003年 | 60篇 |
2002年 | 58篇 |
2001年 | 128篇 |
2000年 | 93篇 |
1999年 | 79篇 |
1996年 | 39篇 |
1993年 | 43篇 |
1992年 | 60篇 |
1991年 | 68篇 |
1990年 | 58篇 |
1989年 | 56篇 |
1988年 | 62篇 |
1987年 | 57篇 |
1986年 | 50篇 |
1985年 | 59篇 |
1984年 | 58篇 |
1983年 | 46篇 |
1982年 | 51篇 |
1981年 | 38篇 |
1979年 | 57篇 |
1978年 | 57篇 |
1977年 | 50篇 |
1976年 | 45篇 |
1975年 | 64篇 |
1974年 | 60篇 |
1973年 | 56篇 |
1972年 | 50篇 |
1971年 | 52篇 |
1969年 | 37篇 |
1968年 | 49篇 |
1967年 | 60篇 |
1966年 | 43篇 |
排序方式: 共有4141条查询结果,搜索用时 0 毫秒
911.
912.
Elementary school children scoring in the highest and lowest 26% or 27% of their classes on the Texas Physical Fitness test were compared for attitude toward physical education and self-concept. Data were collected on the Children's Attitude Inventory Toward Physical Education, a Game of Pairs for Preferences Among School Subjects, and the Children's Self-concept Scale. Analysis of variance indicated significant differences on all tests between boys high in fitness, girls high in fitness, boys low in fitness, and girls low in fitness. Subsequent Scheffé tests indicated that highly fit girls had significantly higher attitude and self-concept scores than boys low in fitness. Highly fit boys had higher self-concepts than boys low in fitness. No other group comparisons were significant. Pearson correlations indicated nonsignificant associations between fitness and attitude and self-concept for the four groups. 相似文献
913.
The effect of thalamic stimulation in processing of verbal stimuli in dichotic listening tasks: a case study 总被引:1,自引:0,他引:1
S C Bhatnager O J Andy E W Korabic R S Tikofsky V K Saxena R S Hellman B D Collier L D Krohn 《Brain and language》1989,36(2):236-251
In dichotic listening tasks, the (dominant) right ear's superiority in processing verbal stimuli has been attributed to its direct anatomic connection with the left dominant hemisphere. The role played by extralinguistic factors, such as attention and functional tuning of the associated cortical structures, has not been carefully examined. This investigation was undertaken to evaluate the effects of the left thalamic electric stimulation on the processing (recognition and recall) of dichotically presented CVC verbal stimuli in a patient being treated for chronic pain. We report the positive effects of electric stimulation (confirmed by increased subcortical metabolic activity using SPECT, a brain imaging technique) on the processing of dichotically presented verbal stimuli. 相似文献
914.
Twenty normal adults participated in two training sessions designed to teach eight novel object words and eight novel action words. Each subject received comprehension and production training and was probed at the end of each session to determine the ability to retrieve lexical items in a naming task. The probe data were also analyzed for phonological accuracy. Reaction time measures for the production probes were recorded to determine differences between action and object words in terms of retrieval difficulty. The results demonstrated a significant difference in early learning of action and object words during comprehension training and production training and in production probes. Object words tended to be learned more easily in both comprehension and production training, and they were retrieved correctly more often in production probes. There were no significant differences in the phonological accuracy between the word types. Reaction time data indicated significant differences in early as well as later learning between action and object words, with object words having significantly shorter rection times as compared with action words. Results are discussed in the context of prior research. 相似文献
915.
Prolonged exposure to a reciprocating motion that is tracked by the eyes results in diminished extent of perceived motion. Investigation of this effect showed that it becomes manifest only in perceived motion that is caused by ocular pursuit, but that it is not an eye muscle effect. It may consist in a changed evaluation of eye movements. The results throw some light on the relations between the processes that are caused by different stimuli for motion. 相似文献
916.
Charles W. Eriksen Nancy Morris Yei -Yu Yeh William O’hara Robert T. Durst 《Attention, perception & psychophysics》1981,30(4):375-385
Bjork and Murray (1977) have presented a feature-specific interactive channels model that predicts perceptual interference between letters presented simultaneously in visual displays. Maximum interference is predicted when a target letter is presented with an identical letter. In their experiment, Bjork and Murray found support for their model, but their results could have occurred artifactually from response biases of their subjects. Santee and Egeth (1980) used a different paradigm that eliminated the possibility of this particular response bias and reported that their data supported the feature-specific model. However, the present paper shows that analysis of their data by Santee and Egeth was incomplete and the comparisons inappropriate. In two experiments that used the Santee and Egeth paradigm, we failed to find support for the feature-specific model when more detailed analyses of the data were undertaken. In a third experiment, one that used the Bjork and Murray paradigm, but with control of response bias, no significant or suggestive evidence was found that feature similarity between noise and target letters affected recognition of the latter. 相似文献
917.
918.
919.
It is proposed that some distance cues are learned when a perceptual parameter that varies with observation distance is regularly associated with objects whose distances are perceived because another distance cue operates. If that is the way distance cues can come into existence, it may be possible to identify a parameter that varies with distance but is not a known distance cue and to show that it functions as one. The slope of regard with which an object on the ground is viewed is such a potential distance cue. Its angle varies approximately with the reciprocal of distance. An experiment was done that showed that this slope angle functions as a distance cue. Subjects who looked through a device that altered slope angles gave estimates of the dimensions of an object on the ground. Perceived sizes, which vary inversely with distance, were found to be altered in accordance with the altered slope angle. 相似文献
920.
By delivering the vertical synch pulse to the maskable interrupt, it is possible to supply the Apple with a functional on-board 60-Hz clock that operates virtually independently of the CPU. This modification makes it easier to program more complex experiments involving independent control over stimulus exposure duration and the timing of response latency. 相似文献