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951.
952.
The primary purpose of the present research was to relate questionnaire-assessed self-reported childhood happiness and events to adulthood happiness in 387 nonclinical participants. Although childhood happiness and adult happiness were found to be significantly correlated (r = .28, p < .001), there was little relationship between reported adult happiness and reported specific childhood events and circumstances. Childhood events and circumstances, however, were much more highly correlated with childhood happiness (R = .64). Thirty-four percent of the persons who said they were unhappy or very unhappy as a child, but only 9% who said they were happy or very happy as a child, reported that they were unhappy or very unhappy as adults. 相似文献
953.
The authors addressed balance control in children from the perspective of skill development and examined the relationship between specific perceptual and motor skills and static and dynamic balance performance. Fifty 11- to 13-year-old children performed a series of 1-legged balance tasks while standing on a force platform. Postural control was reflected in the maximum displacement of the center of mass in anterior-posterior and mediolateral directions. Simple visual, discrimination, and choice reaction times; sustained attention; visuomotor coordination; kinesthesis; and depth perception were also assessed in a series of perceptual and motor tests. The correlation analysis revealed that balancing under static conditions was strongly associated with the ability to perceive and process visual information, which is important for feedback-based control of balance. On the other hand, when greater task demands were imposed on the system under dynamic balancing conditions, the ability to respond to the destabilizing hip abductions-adductions in order to maintain equilibrium was associated with motor response speed, suggesting the use of a descending, feedforward control strategy. Therefore, like adults, 11- to 13-year-old children have the ability to select varying balance strategies (feedback, feedforward, or both), depending on the constraints of a particular task. 相似文献
954.
Reacquisition and transfer of Morse key tapping and finger circling under total peripheral feedback reduction were investigated. 23 medical students were tested. Kinesthetic and tactile feedback were reduced by compression block. The results showed that tapping performance was reacquired to 56.4% of normal and circling to 26.4% by the tenth preshift trials. Strong positive transfer was found for both tasks in Groups 1 and 2. This positive transfer indicated the existence of central, general programming operations. With trials alternating between the two tasks (Group 3) reacquisition curves followed the preshift trials for tapping and circling, showing absence of adverse emotional influence of the block technique. Marked individual differences in performance in the absence of peripheral information were observed, grouping Ss into two distinct categories. 相似文献
955.
In the present work the effect of two task variables on transfer were studied: shape of the track-circular or triangular; and target speed-constant or variable. One or both of these variables was changed on transfer. Experimental conditions were (a) 10 preshift and 10 post-shift trials, and (b) 20 single-trial alternations of two tasks. 22 groups of 12 Ss each were tested. Condition (a) showed positive transfer with single variable change and zero or negative transfer with simultaneous change in two variables, and condition (b) annulled all transfer effects. Results are discussed in terms of commonality between tasks and receptor and perceptual anticipation. 相似文献
956.
Rotations are fundamental to motor control, not only for orienting to stimuli but also in the joint articulations that underlie translational movements. Studying three-dimensional (3-D) rotations of the simplest joint system, the eye, has provided general insights into the neural control of movement. First, in selecting one 3-D eye orientation for each two-dimensional (2-D) gaze direction, the oculomotor system generates a behavior called Listing's law that constrains eye position to a 2-D plane, Listing's plane. This selection is made internally by an inverse kinematic transformation called the Listing's law operator. Second, the oculomotor system incorporates the inherent multiplicative relationship between rotational velocity and position to generate the 3-D movement and position commands required by Listing's law. Finally, the coordinate systems for these commands appear to align with Listing's plane rather than with anatomic structures. Recent investigations have revealed similar behavioral constraints in the orientations of the head and arm, suggesting that the neural mechanisms for Listing's law may have analogues in many motor systems. 相似文献
957.
This study investigated the influence of hemispheric specialization of function on the motor performance of the hands. Right-handed (n=17), ambidextral (n=21), and ambisinistral (n=12) subjects performed Fitts' (1954) reciprocal tapping task under two conditions with each hand. Conditions had the same index of difficulty but differed in movement precision. The left hand of righthanders was superior in the condition requiring the greatest amount of preprogramming. Conversely, the right hand was not superior in the condition having the greatest demand for feedback control. For ambidextrals, left-hand superiority in the relatively preprogrammed condition was also revealed. Ambisinistrals showed no significant difference between conditions with either hand. The results partially support the hypothesis that the motor performance of the hands mirrors the dominant processing mode of their contralateral hemisphere. Failure to find supportive evidence in ambisinistrals is consistent with the contention that they lack hemispheric specialization of function. 相似文献
958.
The study was designed to investigate target acquisition in the vertical plane with emphasis on establishing strategy differences associated with acquisition triggering methods. Eight subjects were tested. Measurements consisted of target acquisition time, eye-head latency differences, velocity of gaze, eyes and head, and head amplitude. Using 3-way repeated measures analyses of variance the results show that the strategy for acquisition of predictable visual targets in vertical plane with the head unrestrained significantly depended on (a) the direction of the gaze motion with respect to the gravity vector (i.e., there is significant up-down asymmetry), (b) the angular distance of the target, and (c) the method of triggering the command to acquire the target—external versus internal. The data also show that when vertical acquisition is compared with triggering methods in the horizontal plane there is a difference in overall strategy for the acquisition of targets with the same spatial distances from straight ahead gaze when both the eyes and head are used. Among the factors contributing to the difference in strategy for vertical target acquisition are the gravitational vector, the relationship of target displacement and vestibular activitation, biomechanical and neural control asymmetries, and the difference in the vertical field of view. 相似文献
959.
In this study, we utilized a large undergraduate sample (N = 536), oversampled for the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text revision [DSM–IV–TR]; American Psychiatric Association, 2000) obsessive–compulsive personality disorder (OCPD) pathology, to compare 8 self-report measures of OCPD. No prior study has compared more than 3 measures, and the results indicate that the scales had only moderate convergent validity. We also went beyond the existing literature to compare these scales to 2 external reference points: their relationships with a well-established measure of the five-factor model of personality (FFM) and clinicians' ratings of their coverage of the DSM–IV–TR criterion set. When the FFM was used as a point of comparison, the results suggest important differences among the measures with respect to their divergent representation of conscientiousness, neuroticism, and agreeableness. Additionally, an analysis of the construct coverage indicated that the measures also varied in terms of their representation of particular diagnostic criteria. For example, whereas some scales contained items distributed across the diagnostic criteria, others were concentrated more heavily on particular features of the DSM–IV–TR disorder. 相似文献
960.