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211.
Observers' perceptions of the three-dimensional structure of smoothly curved surfaces defined by patterns of image shading were investigated under varying conditions of illumination. In five experiments, observers judged the global orientation and the motion of the simulated surfaces from both static and dynamic patterns of image shading. We found that perceptual performance was more accurate with static than with dynamic displays. Dynamic displays evoked systematic biases in perceptual performance when the surface and the illumination source were simulated as rotating in opposite directions. In these conditions, the surface was incorrectly perceived as rotating in the same direction as the illumination source. Conversely, the orientation of the simulated surfaces was perceived correctly when the frames making up the apparent-motion sequences of the dynamic displays were presented as static images. In Experiment 6, moreover, the results obtained with the computer-generated displays were replicated with solid objects. 相似文献
212.
The effect of pyridoxine (Vitamin B-6) on dreaming was investigated in a placebo, double-blind study to examine various claims that Vitamin B-6 increases dream vividness or the ability to recall dreams. 12 college students participated in all three treatment conditions, each of which involved ingesting either 100 mg B-6, 250 mg B-6, or a placebo prior to bedtime for a period of five consecutive days. The treatment conditions were completely counterbalanced and a two-day wash-out period occurred between the three five-day treatment blocks. Morning self-reports indicated a significant difference in dream-salience scores (this is a composite score containing measures on vividness, bizarreness, emotionality, and color) between the 250-mg condition and placebo over the first three days of each treatment. The data for dream salience suggests that Vitamin B-6 may act by increasing cortical arousal during periods of rapid eve movement (REM) sleep. An hypothesis is presented involving the role of B-6 in the conversion of tryptophan to serotonin. However, this first study needs to be replicated using the same procedures and also demonstrated in a sleep laboratory before the results can be considered certain. 相似文献
213.
Gross M 《Journal of the history of the behavioral sciences》2002,38(1):27-42
Edward A. Ross, a key figure in the early history of American sociology, developed a conceptualization of natural and social changes of the material environment that is virtually forgotten today. In this paper, these topics are discussed and located vis-à-vis Ross's intellectual contemporaries and their general take on the nature/society relationship. It is argued that ecological and sociological ideas in the early twentieth century influenced one another and, in the case of Ross, produced a perspective of social change that tried to include the dynamics of nature. 相似文献
214.
M. H. Bond (2002), A. P. Fiske (2002), S. Kitayama (2002), and J. G. Miller (2002) joined D. Oyserman, H. M. Coon, and M. Kemmelmeier (2002) in highlighting limitations of the individualism-collectivism model of culture. Concern is warranted; nevertheless, individualism-collectivism helps structure discourse on the influence of culture on the mind. To avoid level-of-analysis entanglements, Oyserman et al. propose an integrative model that includes distal, proximal, and situated cultural features of societies and internalized models of these features, highlights the importance of subjective construal, and uses evolutionary perspectives to clarify the basic problems cultures address. Framed this way, it is clear that, depending on situational requirements, both individualism- and collectivism-focused strategies are adaptive; thus, it is likely that human minds have adapted to think both ways. 相似文献
215.
This study investigated the effect of cooperative learning on eighth grade students' performance in algebra. 54 boys and 57 girls in four middle-school mathematics classes of Grade 8 in the UAE participated. Over a 3-wk. period, two classes (57 students) were taught using a cooperative learning method, and the other two classes (54 students) were taught using the traditional lecture method. Analysis of covariance using pretest scores as a covariant showed no statistically significant increase in the algebra performance for students in the cooperative learning groups compared with the traditional groups. However, boys in the cooperative setting improved significantly on the performance test compared with boys in the traditional setting. 相似文献
216.
217.
Enumeration of briefly presented items by the chimpanzee (Pan troglodytes) and humans (Homo sapiens)
In this study, we compared the performances on an enumeration task (numerical labeling task) of 1 chimpanzee (Pan troglodytes) and 4 humans. In this task, two types of trials, with different exposure durations of the sample that was to be enumerated, were used. In the unlimited-exposure trials, the sample remained on until the subject made a choice. In the brief-exposure trials, the sample was presented for 100 msec and then was masked. The results show clear differences between the different species. The main differences had to do with accuracy during the unlimited trials and response times during the brief trials. Detailed analyses of the pattern of response times for the chimpanzee and of looking-back behavior during the task suggests that the enumeration process underlying the subject's performance was not counting but estimation. 相似文献
218.
The suffix effect has generally been viewed as reflecting an automatic component involving the terminal item and a component susceptible to top-down influences involving the preterminal items (Balota & Engle, 1981). Recent findings have raised questions about this widely accepted view of the suffix effect by showing that the terminal component is not insensitive to top-down influences (Bloom & Watkins, 1999). In the present study, we attempted to uncover the source of these contradictory findings by assessing whether the terminal item's susceptibility to top-down influences might depend on subjects' first-hand experience of the extent to which recall is affected by the suffix. Furthermore, we examined whether age differences in the suffix effect could be attributed to age-related declines in inhibitory processes. Our findings supported both predictions. 相似文献
219.
Tagliabue, Zorzi, Umiltà, and Bassignani (2000) showed that one's practicing of a spatially incompatible task influences performance in a Simon task even when the interval between the two tasks is as long as 1 week. In the present study, three experiments were conducted to investigate whether such an effect could be found in a cross-modal paradigm, whereby stimuli in the two tasks were presented in different modalities. Subjects performed either compatible or incompatible mappings in an acoustic spatial compatibility task and, after an interval of 5 min, 24 h, or 7 days, performed a visual Simon task. Results show that the spatially incompatible mapping task affected performance in the Simon task: The Simon effect was absent for all three intervals. This pattern is similar to the results of the Tagliabue et al. study, in which both tasks were performed in the same (visual) modality. Our findings disprove possible explanations based on episodic/contextual effects and support the hypothesis of a long-lasting spatial remapping that is not modality specific. 相似文献
220.
Psycholinguistic speech production models assume that lexical stress is stored and accessed separately during phonological encoding. We address the questions of the storage and computation of lexical stress in a case study of an Italian-speaking patient with an impairment of lexical stress assignment in naming, reading, and repeating single words. The patient's stress error pattern and his performance on tasks examining lexical stress in perception suggest an impairment in the retrieval of the stress pattern of irregular words. In contrast, his assignment of stress to nonstored phonological forms suggests that the computation of stress is unimpaired. 相似文献