全文获取类型
收费全文 | 70944篇 |
免费 | 2940篇 |
国内免费 | 25篇 |
专业分类
73909篇 |
出版年
2020年 | 697篇 |
2019年 | 890篇 |
2018年 | 1202篇 |
2017年 | 1211篇 |
2016年 | 1293篇 |
2015年 | 959篇 |
2014年 | 1132篇 |
2013年 | 5244篇 |
2012年 | 2111篇 |
2011年 | 2237篇 |
2010年 | 1419篇 |
2009年 | 1389篇 |
2008年 | 2001篇 |
2007年 | 2045篇 |
2006年 | 1840篇 |
2005年 | 1659篇 |
2004年 | 1522篇 |
2003年 | 1400篇 |
2002年 | 1536篇 |
2001年 | 2375篇 |
2000年 | 2356篇 |
1999年 | 1776篇 |
1998年 | 825篇 |
1997年 | 728篇 |
1996年 | 738篇 |
1993年 | 655篇 |
1992年 | 1480篇 |
1991年 | 1369篇 |
1990年 | 1369篇 |
1989年 | 1242篇 |
1988年 | 1211篇 |
1987年 | 1149篇 |
1986年 | 1224篇 |
1985年 | 1233篇 |
1984年 | 1047篇 |
1983年 | 949篇 |
1982年 | 677篇 |
1981年 | 657篇 |
1979年 | 1092篇 |
1978年 | 793篇 |
1975年 | 904篇 |
1974年 | 991篇 |
1973年 | 1068篇 |
1972年 | 894篇 |
1971年 | 855篇 |
1970年 | 749篇 |
1969年 | 801篇 |
1968年 | 1005篇 |
1967年 | 923篇 |
1966年 | 777篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
971.
9 stutterers and 9 nonstutterers were administered a dichotic digits test under conditions of free recall and directed attention. Analysis indicated right-ear preference for both groups and no differences between the free recall and directed listening conditions. Results are discussed in relation to previous studies in which dichotic digit-stimuli were presented to stutterers. 相似文献
972.
D J Schiano 《Perceptual and motor skills》1986,63(3):1151-1155
The parallel-lines illusion provides a prototypical example of visual-size assimilation, where the size of a test element is phenomenally skewed towards (or "averaged with") that of a context element. Most assimilation theories predict that distortion should decrease with spatial separation between context and test lengths. However, there is some disagreement about the nature of the function relating sizes of context and test elements and magnitude of assimilation. The present study tests the limits of assimilation in the parallel-lines configurations by observing the effects of a wide range of context/test size ratios, repeated over two disparate levels of spatial separation. The results replicate and extend 1979 findings by Brigell and Uhlarik, confirming that assimilation rises to a peak at midrange size ratios, only to decrease continuously as the ratios become more extreme. The functions were nonmonotonic and similar in shape for both levels of spatial separation, with an over-all decrease in distortion for configurations with the larger separation. 相似文献
973.
The purpose of the study was to document children's perception of parental exercise, relating these perceptions to (1) the self-reported parents' habits of exercise, and (2) the children's own activity patterns. The subjects were 198 students of both sexes, aged 12 to 14 yr. and enrolled in school Grades 7 to 9. A standard questionnaire assessed their perceptions of parental and personal physical activity. Both parents of each subject also reported their respective levels of habitual physical activity. Congruence between the children's perceptions and the self-reported exercise habits of the opposite-sex parent differed for boys and girls, increasing for boys and decreasing for girls between Grades 7 and 9. No significant associations were observed between the children's perception of parental exercise patterns and their own like habits. This suggests that during adolescence parental influences are minimized by other factors, personal or environmental. 相似文献
974.
In three experiments, subjects learned to classify dot patterns into three categories represented by either three, six, or nine exemplars. Following learning, subjects were tested on an additional set of patterns, which included patterns from the learning phase, the category objective prototypes, and new distortions of the objective prototypes. Also included in the test set were empirical prototypes and distortions of empirical prototypes. Empirical prototypes were derived by averaging feature values of category exemplars in the learning phase. The overall results revealed that empirical prototypes were classified more accurately than were objective prototypes. In addition, a pattern of convergence in error rates was observed for distortions of the objective and empirical prototypes as category set size increased, but this same pattern was not observed for the objective and empirical prototypes themselves. This lack of convergence for the prototypes is inconsistent with explanations of the category set size effect that rely on the central limit theorem. 相似文献
975.
Studied identification using a meta-contrast design. The first stimulus was the word 'I'. The second stimulus depicted an aggressor and a victim facing each other. The subliminal 'I' was flashed on either the victim or on the aggressor, or completely withheld. The subjects were 33 school children, aged 10–12 years. They also took a percept-genetic (PG) test of creativity, measuring willingness to return to and recognize early conceptions of a stimulus picture (a still-life). The results showed that the creative children reacted with less anxiety and defense when manipulated to identify with the aggressor than with the victim. The uncreative children showed the opposite reaction, namely a preference for the passive, surrendering victim. 相似文献
976.
977.
Roger J. Bowden 《Psychometrika》1986,51(2):313-325
It is commonly held that even where questionnaire response is poor, correlational studies are affected only by loss of degrees of freedom or precision. We show that this supposition is not true. If the decision to respond is correlated with a substantive variable of interest, then regression or analysis of variance methods based upon the questionnaire results may be adversely affected by self-selection bias. Moreover such bias may arise even where response is 100%. The problem in both cases arises where selection information is passed to the score indirectly via the disturbance or individual effects, rather than entirely via the observable explanatory variables. We suggest tests for the ensuing self-selection bias and possible ways of handling the ensuing problems of inference.The author would like to thank members of the Psychology Department at UWA for references on the illustrative example, namely the effects of sex-stereotyping on achievements in mathematics; thanks are also due to the anonymous reviewers whose comments resulted in material improvements to the paper. 相似文献
978.
979.
The authors contend that there are logical inconsistencies in a theory put forth by Michael Green and Daniel Wikler ("Brain death and personal identity," Philosophy and Public Affairs 1980 Winter; 9(2): 105-133) to justify the brain death concept of death. Green and Wikler had asserted that individuals cease to exist and are dead when the criteria for continuity in their personal identity are not met. Having argued that the theory of personal identity is misguided, Agich and Jones suggest that further research into the ontological foundation of brain death concepts should begin, not by rejecting medical or moral considerations, but by carefully defining the main competing concepts of brain death as brain stem death, cerebral death, death of the brain as a whole, and whole brain death, and then by relating these concepts to the ontological conditions for being a live individual or person. 相似文献
980.