全文获取类型
收费全文 | 51260篇 |
免费 | 1993篇 |
国内免费 | 20篇 |
出版年
2020年 | 528篇 |
2019年 | 725篇 |
2018年 | 931篇 |
2017年 | 979篇 |
2016年 | 1015篇 |
2015年 | 696篇 |
2014年 | 914篇 |
2013年 | 4039篇 |
2012年 | 1602篇 |
2011年 | 1669篇 |
2010年 | 1061篇 |
2009年 | 1026篇 |
2008年 | 1468篇 |
2007年 | 1517篇 |
2006年 | 1375篇 |
2005年 | 1192篇 |
2004年 | 1171篇 |
2003年 | 1085篇 |
2002年 | 1090篇 |
2001年 | 1536篇 |
2000年 | 1529篇 |
1999年 | 1146篇 |
1998年 | 557篇 |
1997年 | 507篇 |
1996年 | 486篇 |
1995年 | 495篇 |
1994年 | 475篇 |
1992年 | 964篇 |
1991年 | 882篇 |
1990年 | 950篇 |
1989年 | 834篇 |
1988年 | 855篇 |
1987年 | 793篇 |
1986年 | 801篇 |
1985年 | 774篇 |
1984年 | 667篇 |
1983年 | 653篇 |
1982年 | 483篇 |
1979年 | 779篇 |
1978年 | 589篇 |
1975年 | 644篇 |
1974年 | 711篇 |
1973年 | 753篇 |
1972年 | 578篇 |
1971年 | 576篇 |
1970年 | 492篇 |
1969年 | 571篇 |
1968年 | 699篇 |
1967年 | 644篇 |
1966年 | 539篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
Robert L. Savoy 《Attention, perception & psychophysics》1984,36(6):571-576
A McCollough effect was induced in subjects by having them view typical adapting stimuli binocularly for 5 min. In the control condition, the strength of the McCollough effect was measured 20 min after the end of the adaptation. The strength was measured during monocular and binocular viewing of a test pattern via a color cancellation technique. Monocular strengths for the two eyes of a given subject were equal to each other and slightly weaker than the binocular strength. In the test condition, 15 min of the 20 min between adaptation and testing were spent monocularly viewing black and white gratings of the same orientation and spatial frequency as the adapting gratings. The strength of the effect as measured ipsilaterally was markedly decreased from that in the control condition. The strength of the effect as measured with the contralateral eye showed only a small decrease from that of the control condition. This finding is relevant to various models of the McCollough effect and related color aftereffects, especially those that posit a “learning” type of mechanism between achromatic spatial channels (which exhibit clear interocular transfer of various achromatic effects) and monocular color channels. 相似文献
912.
A survey of academic psychologists was taken to determine present use of computers in instruction, willingness to use good education software, and kinds of potential uses of computers in psychology courses. A majority of the respondents reported using computers in instruction. Respondents indicated substantial willingness to adopt computer-based courseware. Respondents believed that a variety of uses, including classroom demonstrations and student experiments, would facilitate student learning. The results of the survey are compared with the instructional modules the task force is developing. 相似文献
913.
Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations is addressed. Sampling differences for small species occupying relatively small home ranges indicate that fewer locations may be sufficient to allow for a reliable estimate of home range. Intraspecific variability in social status (group member, loner, resident, transient), age, sex, reproductive condition, and food resources also have to be considered, as do season, habitat, and differences in sampling and analytical methods. Comparative data still are needed. 相似文献
914.
Rebecca Logsdon Larry Hochhaus Harold L. Williams O.H. Rundell Dale Maxwell 《Acta psychologica》1984,55(2):179-193
An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated. 相似文献
915.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents. 相似文献
916.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings. 相似文献
917.
918.
919.
B F Skinner 《Journal of the experimental analysis of behavior》1984,41(2):217-221
920.
Rats' lever pressing produced sucrose reinforcers on a variable-interval schedule where, in different conditions, the duration of a stimulus presented immediately after reinforcement was either correlated or uncorrelated with the duration of the current interreinforcement interval. Under the baseline schedule, in which no stimulus was presented, the minimum interreinforcement interval was 8 s and the mean postreinforcement pause of each subject approximated this value. Response rates increased slowly over the first 10 to 15 s and then remained roughly constant throughout the remainder of the interval. In both the correlated and uncorrelated conditions, the added stimulus resulted in the postreinforcement pauses lengthening to values in excess of the duration of the preceding stimulus. This resulted in a poststimulus pause which was, in most cases, roughly constant irrespective of the duration of the preceding stimulus, or of the reinforcement contingencies prevailing immediately after stimulus offset. Local response-rate patterns in the uncorrelated conditions were similar to those obtained under the baseline schedule in which no stimulus was presented. However, in the correlated condition local response rates increased across the remainder of the interreinforcer interval. Further, the rate of acceleration was inversely related to the duration of the preceding stimulus. These results show that a correlation between stimulus duration and the ensuing time to reinforcement can control behavior—a type of temporal control not previously reported. 相似文献