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111.
The transformation of functions refers to the untrained acquisition of stimulus functions among members of stimulus equivalence classes or relational frames. Although it is widely assumed that contextual control over the transformation of fuctions must exist, this has not yet been conclusively demonstrated in laboratory studies. Four experiments are reported in which (a) stimulus equivalence classes were established, (b) a conditional stimulus function was trained for one member of each of the classes, and (c) multiple-exemplar procedures were used to train and test for contextual control over the transformation of the stimulus function within the classes and to assess whether it generalized to new equivalence classes. Although a significant amount of training was required, the procedures ultimately resulted in the contextual control of function transformation for 9 of 10 participants and generalized contextual control for 4 of 5 participants.  相似文献   
112.
In karate, performance also depends on a correct body shape, and the repeatability of standardized movements conditions the effectiveness of techniques. The execution of mae-geri-keage (frontal snap kick) was studied in 13 karateka (1st-5th dan). The 3D trajectories of 13 body landmarks were analyzed by an optoelectronic instrument while each karateka performed 10 repetitions of the movement. For each karateka and repetition, the standard deviations of the spatial coordinates x, y, z for each landmark were computed. A total standard deviation of the single participant was also calculated. Two experienced karateka performed with the best repeatability (smaller standard deviation) while executing the studied kick. Generally, the best repeatability was observed in the horizontal plane. The lower variability was observed in hips and head. Ankle and knee of the dominant limb had the worse. The method could detect athletes particularly gifted for the discipline. Moreover, it could help in the identification of those parts of body that do not repeat the movement with the desired precision.  相似文献   
113.
This study describes a method of modeling human trunk and whole body backward bending and suggests a possible neural control strategy. The hypothesis was that the control system can be modeled as a linear feedback system, in which the torque acting at a given joint is a function of the state variables (angular positions and angular velocities). The linear system enabled representation of the feedback system by a gain matrix. The matrix was computed from the kinematics recorded by a movement analysis system and from the joint torques calculated by inverse dynamics. To validate the control model, a comparison was made between the angular kinematics yielded by the model and the experimental data. Moreover, for all subjects, the same relationships between feedback coefficients were found although gain values were different. The study showed that the feedback system is an appropriate model of the strategy from performing an accurate controlled trunk or whole body backward bending in the sagittal plane.  相似文献   
114.
We measured driving performance (lane-keeping errors, driving times, and glances away from the road scene) in a video driving simulator for 24 volunteers who each drove alone on a 10.6-km multicurved course while simultaneously placing calls on a mobile phone subscribed to a voice-activated dialing system. Driving performance also was measured for the same distance while participants manually dialed phone numbers and while they drove without dialing. There were 22% fewer lane-keeping errors (p<.01) and 56% fewer glances away from the road scene (p<.01) when they used voice-activated dialing as compared to manual dialing. Significantly longer driving times in both of the dialing conditions as compared to the No Dialing condition are discussed in terms of the hypothesis that drivers decrease driving speed to compensate for the demands of the secondary phone tasks.  相似文献   
115.
Correlations between scores on the Spence Children's Anxiety Scale, a questionnaire for measuring symptoms of anxiety disorders and a report of school functioning by teachers were computed for 317 primary school children and 13 teachers in The Netherlands. Analysis showed a small but significant negative correlation between scores for total anxiety and school functioning (r = -.20, p < .001). The finding is consistent with the notion that high symptoms indicating anxiety disorders in children are accompanied by less optimal functioning in school.  相似文献   
116.
The purpose of the present study was to examine the structure of empathy using a hierarchical approach, and to compare the dimensions of empathy with measures of social functioning, in order to contribute to the understanding of the nature of empathy. The dimensionality of the Interpersonal Reactivity Index, which comprises four subscales (empathic concern, perspective taking, fantasy and personal distress) was examined using confirmatory factor analysis. Relations with the Social Skills Inventory were also investigated. A sample of 127 applicants for places on nursing and social work undergraduate programs participated in the study. The study findings indicate that empathy is hierarchically organized, with one general dimension at the apex. The general factor is identical to empathic concern and this dimension overlaps to a great extent with perspective taking and fantasy. The findings also indicate that the general dimension constitutes an integrated entirety, with its main emphasis on emotional reactivity by also involving cognitive processes.  相似文献   
117.
Suggests various ways in which the concept of emotional intelligence (EI) can inform community research and action. Begins by defining EI and reviewing the growing body of research on its contribution to educational, health, and occupational outcomes. Next distinguishes between EI and the related concept of emotional and social competence. Then considers the connection between EI and several topics of interest to community action researchers including prevention and wellness promotion, implementation and dissemination of innovative programs, community development, and the value of diversity. Concludes by suggesting that the ecological perspective can help inform research and practice relating to EI.  相似文献   
118.
Nonspatial attentional shifts between audition and vision   总被引:2,自引:0,他引:2  
This study investigated nonspatial shifts of attention between visual and auditory modalities. The authors provide evidence that the modality of a stimulus (S1) affected the processing of a subsequent stimulus (S2) depending on whether they shared the same modality. For both vision and audition, the onset of S1 summoned attention exogenously to its modality, causing a delay in processing S2 in a different modality. That undermines the notion that auditory stimuli have a stronger and more automatic alerting effect than visual stimuli (M. I. Posner, M. J. Nissen, & R. M. Klein, 1976). The results are consistent with other recent studies showing cross-modal attentional limitation. The authors suggest that such cross-modal limitation can be produced by simply presenting S1 and S2 in different modalities and that central processing mechanisms are also, at least partially, modality dependent.  相似文献   
119.
Cross-modal illusory conjunctions (ICs) happen when, under conditions of divided attention, felt textures are reported as being seen or vice versa. Experiments provided evidence for these errors, demonstrated that ICs are more frequent if tactile and visual stimuli are in the same hemispace, and showed that ICs still occur under forced-choice conditions but do not occur when attention to the felt texture is increased. Cross-modal ICs were also found in a patient with parietal damage even with relatively long presentations of visual stimuli. The data are consistent with there being cross-modal integration of sensory information, with the modality of origin sometimes being misattributed when attention is constrained. The empirical conclusions from the experiments are supported by formal models.  相似文献   
120.
The authors examined whether 2 computational models of reading, the dual-route cascaded model (M. Coltheart, K. Rastle, C. Perry, R. Langdon, & J. C. Ziegler, 2001) and the connectionist 2-layer model (M. Zorzi, G. Houghton, & B. Butterworth, 1998), were able to predict the pattern that the length effect found in reading aloud is larger in German than in English (J. C. Ziegler, C. Perry, A. M. Jacobs, & M. Braun, 2001). The results showed that the dual-route cascaded model, which uses a serial mechanism for assembling phonology, successfully predicted this cross-language difference. In contrast, the connectionist model of Zorzi et al. (1998) predicted the opposite: a larger length effect in English than in German. Both the success of one model and the failure of the other highlight fundamental differences between 2 major classes of computational models.  相似文献   
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