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891.
Van Houten R Malenfant JE Zhao N Ko B Van Houten J 《Journal of applied behavior analysis》2005,38(3):289-301
The Florida Department of Transportation used a series of changeable-message signs that functioned as freeway guide signs to divert traffic to Universal Theme Park via one of two eastbound exits based on traffic congestion at the first of the two exits. An examination of crashes along the entire route indicated a statistically significant increase in crashes at the first eastbound exit following the actuation of the system. Furthermore, all of the crashes occurred in close proximity to the exit gore (the crosshatched area at exits that drivers are not supposed to enter or traverse) at the first exit. In Experiment 1, behavioral data were collected using an alternating treatments design. These data revealed that reassigning the exit signs was effective in producing a change in the percentage of drivers using each of the two exits. These data also showed that the reassignment of the theme park exit was associated with an increase in the percentage of motor vehicle conflicts that consisted of vehicles cutting across the exit gore. An analysis revealed that the method used for switching the designated or active theme park exit on the series of changeable-message signs led to the presentation of conflicting messages to some motorists, thus resulting in erratic driving behavior (cutting across the exit gore). In Experiment 2, the treatment evaluated the use of a phased method of switching the designated theme park exit to eliminate the delivery of conflicting messages. The new method for switching the designated theme park exit was not associated with an increase in motorists cutting across the exit gore. 相似文献
892.
We present a series of experiments in which human subjects were tested with a well-known combinatorial problem called the 15-puzzle and in different-sized variants of this puzzle. Subjects can solve these puzzles reliably by systematically building a solution path, without performing much search and without using distances among the states of the problem. The computational complexity of the underlying mental mechanisms is very low. We formulated a computational model of the underlying cognitive processes on the basis of our results. This model applied a pyramid algorithm to individual stages of each problem. The model's performance proved to be quite similar to the subjects' performance. 相似文献
893.
Kitts RL 《Adolescence》2005,40(159):621-628
Suicide among gay adolescents is a major public health concern, but it is still under-emphasized within mainstream healthcare. This article brings together information garnered from past studies, articles, and experiences to create a more in-depth understanding of why gay adolescents are at a higher risk for suicide. By creating a better understanding, this article attempts to push forward the significance of this issue and encourages physicians to take a more active role in suicide prevention. The article initially explores why issues involving homosexuality are seldom discussed and provides evidence for an increased risk in suicide among gay adolescents. By addressing major psychosocial issues faced by gay adolescents, it spends the majority of time facilitating an understanding of the increased risk. In this article "gay" refers to homosexual males and females, and bisexuals unless otherwise indicated. 相似文献
894.
Past research has suggested that children who stutter (CWS) may have less well-developed language skills than fluent children, and that such relative linguistic deficiencies may play a role in precipitating their disfluencies. However, data to support this position are primarily derived from results of standardized diagnostic inventories, which are originally designed to identify frank language impairment. Nonword repetition has emerged as a more sensitive measure of children's linguistic abilities. In this exploratory study, eight CWS (mean age 5:10, range 4:3-8:4) were compared to eight normally developing children (ND) (mean age 5:9, range 4:1-8:4) in their ability to repeat the nonwords of the Children's Test of Nonword Repetition. CWS performed more poorly than NS on measures of Number of Words Correct and Number of Phoneme Errors at all nonword lengths, although statistical differences were observed only for 3-syllable nonwords. When lexical stress of the nonwords was varied to a non-English stress pattern, all participants repeated the stimuli with less accuracy, and the CWS again exhibited more errors than NS. Fluency for the CWS group did not change systematically with increasing nonword length. These preliminary findings are interpreted in light of a number of extant theories of the underlying deficit in childhood stuttering. We conclude that children who stutter may have diminished ability to remember and/or reproduce novel phonological sequences, and that further investigation into this possibility may shed light on the emergence and characteristics of childhood stuttering. EDUCATIONAL OBJECTIVES: After completing this activity, the learner will: (1) be able to evaluate the research support for a linguistic component to stuttering; (2) describe the use of nonword repetition as an experimental and assessment device with children with SLI and children who stutter; (3) suggest future directions for research to further refine the potential role that linguistic encoding plays in the etiology and persistence of stuttering. 相似文献
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Li SC 《Psychological bulletin》2003,129(2):171-194
The author reviews reemerging coconstructive conceptions of development and recent empirical findings of developmental plasticity at different levels spanning several fields of developmental and life sciences. A cross-level dynamic biocultural coconstructive framework is endorsed to understand cognitive and behavioral development across the life span. This framework integrates main conceptions of earlier views into a unifying frame, viewing the dynamics of life span development as occurring simultaneously within different time scales (i.e., moment-to-moment microgenesis, life span ontogeny, and human phylogeny) and encompassing multiple levels (i.e., neurobiological, cognitive, behavioral, and sociocultural). Viewed through this metatheoretical framework, new insights of potential interfaces for reciprocal cultural and experiential influences to be integrated with behavioral genetics and cognitive neuroscience research can be more easily prescribed. 相似文献
897.
本文以智力的约定性为立论,把超越界定为智力的约定性的广度、深度和效度的大幅度提高。将斯腾伯格对智力的研究放到智力理论研究的历史过程中,对斯腾伯格的三元智力理论及成功智力理论对IQ的超越做了分析。指出传统IQ是学业差异约定,三元智力是多元权变约定,成功智力是人生成功约定,后者都是对前者的超越,成功智力是对IQ的再次超越。最后尝试性地提出智力约定性的“树”的隐喻。本文对智力理论的研究和教育实践有参考价值。 相似文献
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本文指出西方人格理论实际上是研究者建构的对人性的图解或模式,并对莱波曼的“人性的基本宗旨”加以改造,从五个维度对西方的四大主要人格理论的人性观作了剖析,指出:建立一个更加合乎现实的人格理论必须具有一种综合性的人性观。 相似文献