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891.
Previous work has demonstrated that infants' thresholds for a pure tone are elevated by a masker more than would be predicted from their critical bandwidths. The present studies explored the nature of this additional masking. In Experiment 1, detection thresholds of 6-month-old infants and of adults for a 1-kHz tone were estimated under three conditions: in quiet, in the presence of a 4- to 10-kHz bandpass noise at 40 dB SPL, and in the presence of the same noise at 50 dB SPL. The noise was gated on at the beginning of each trial. Adult thresholds were the same in all three conditions, indicating that little or no sensory masking took place in the presence of the noise. Infant thresholds were about 10 dB higher in the presence of the noise. We term this effect distraction masking. In Experiment 2, the effect of gating the noise on at trial onset was examined. Thresholds for the same tone were estimated in quiet and in the presence of the band-pass noise at 40 dB SPL, but the noise was presented continuously during the session. Under these conditions, distraction masking was still observed for infants. These findings suggest that a masker can have nonsensory effects on infants' performance in a psychoacoustic task.  相似文献   
892.
The current view that the Simon effect (Simon & Small, 1969) reflects stimulus-response compatibility (SRC) is questioned. Previous accounts of the Simon effect have overlooked stimulus congruity (SC), the correspondence relation borne by the two simultaneous aspects of the stimulus, a factor inevitably confounded in the Simon paradigm with irrelevant spatial S-R correspondence. The Hedge and Marsh (1975) reversal effect, replicated in Experiment 1, is reinterpreted as decisive evidence that the Simon effect is entirely accounted for by SC. Furthermore, in Experiment 2 irrelevant S-R correspondence was manipulated in the absence of any variation of SC, and the Simon effect vanished. It is concluded that the Simon effect, contrary to current opinion, represents a spatial variant of the Stroop effect and is irrelevant to the SRC issue. The view that mental operations proceed automatically at the stage of response determination loses one of its strongest empirical arguments.  相似文献   
893.
The patient was a 61-year-old female who suffered from the sudden attack of a speech disorder. The episodes of speech disorder lasted for less than 1 min, but occurred several times a day, paroxysmally. A CT revealed a low density area on the surface of the left frontal lobe and an EEG showed an abnormal wave at the frontoparietal area, more dominantly on the left. This condition was diagnosed as a kind of epilepsy. The paroxysmal speech disorder occurred very often during the 2 months after the first episode. However, with therapy using anticonvulsives and antibiotics, the condition began to improve after 4 months and disappeared completely after 6 months. It is assumed that the inflammatory change which occurred at the frontal lobe stimulated the supplementary motor area paroxysmally, and subsequently the speech disorder occurred as a kind of epilepsy.  相似文献   
894.
Using a variant of the minimal group paradigm (Tajfel and Turner, 1986), this study tested the effects of power, status and group numbers on intergroup behaviours and perceptions. Subjects (N = 160) were categorized into groups that varied on status (high or low), power (dominant or subordinate) and group numbers (majority or minority) variables within a 2 × 2 × 2 experimental design. Based on their evaluations of others' creative products, subjects distributed credit points to ingroup and outgroup others using the Tajfel matrices. Results showed that dominant group members were much more discriminatory and less parity oriented towards outgroup others than subordinate group members. High status group members were more discriminatory and less parity oriented than low status group members. Minority group members who were dominant and of high status were highly discriminatory and were unique in showing no parity whatsoever towards outgroup others. Subordinate low status minorities did not discriminate and were exceptional in showing out-group favouritism. Relative to group status and group numbers, group power seemed more predictive of actual discriminatory behaviour. Group status accounted for the greatest variance in social identification and intergroup perceptions measures. Results also showed that social categorization was sufficient to elicit more in-group than outgroup liking amongst all group members regardless of their position in the intergroup structure. Overall, this study indicated that power, status and group numbers independently and in combination, have a strong impact on intergroup behaviours and perceptions.  相似文献   
895.
In this article, the author problematizes the process of humanizing education in the era of perestroika and glasnost. Identifying herself as a democratic socialist, Kohli invites her Soviet colleagues to acknowledge the criticisms of liberal capitalism before they move headlong in that direction. In deconstructing such taken-for-granted concepts as individualism, democracy, market economy, and community, Kohli suggests that both the West and the East could benefit from re-visiting their respective revolutionary traditions at this crucial historical time.  相似文献   
896.
Normative data on position sense in the knee joint were obtained from a population of young adults (N = 46, mean age: 22). Kinaesthetic and visual evaluation of the knee joint angle was measured in crossmodal and intramodal matching tasks. In terms of absolute errors, the scores, although similar in both crossmodal tasks, were significantly lower in the unimodal matching task; the subjects' laterality had no significant effects. In terms of signed errors, the scores had opposite polarities between the kinaesthetic-visual and the visual-kinaesthetic tasks; moreover, the kinaesthetic intramodal task showed an obvious laterality bias. The angle reference value was found to affect the magnitude and sign of error variably depending on the task. The smallest errors were observed around the resting position in crossmodal matching, whereas they increased monotonically from extension to flexion in unimodal kinaesthetic matching. The data are interpreted in terms of the underlying physiological mechanisms and psychophysical determinants. Some clinical and sport applications are suggested.  相似文献   
897.
Describes (a) the effects of a social-influences-based drug prevention program (the Midwestern Prevention Project) on the mediating variables it was designed to change and (b) the process by which the effects on mediating variables changed use of drugs (tobacco, alcohol, and marijuana). Students in 42 middle schools and junior high schools in Kansas City, Missouri, and Kansas City, Kansas, were measured in the fall of 1984 (N = 5,065) and again 1 year later (N = 5,008) after 24 of the schools had been through the program. Compared to students in control schools, students in program schools became less likely to express belief in the positive consequences of drug use, less likely to indicate that they would use such drugs in the future, more likely to report that their friends were less tolerant of drug use, and more likely to believe that they were better able to communicate with their friends about drug or school problems. Change in perceptions of friends' tolerance of drug use was the most substantial mediator of program effects on drug use. There was evidence that intentions to use and beliefs about the positive consequences of use may also mediate program effects on drug use.  相似文献   
898.
Spontaneous behavior of kittens (Felis catus) was filmed from birth until the end of Month 5 and coded according to Piagetian criteria of sensorimotor intelligence (SI) and object permanence (OP). Data revealed that Stages 2, 3, and 4 of SI were reached at Days 10, 26, and 45, respectively, whereas Stages 2, 3, and 4 of OP were reached at Days 31, 37, and 41, respectively. Spontaneous search behavior was exhibited both in searching for an object that disappeared and in hiding while moving toward a target object. From Day 45 on, search behavior was integrated into a playful social interaction in the form of hide-and-seek. Hence, kittens' spontaneous activity provided them with contexts in which OP was necessary for activity. Lastly, it is proposed that the mobility of both social and physical objects triggered circular activity in this species.  相似文献   
899.
900.
Physical inactivity has increasingly affected public health in the United States during the COVID-19 pandemic as it is associated with chronic diseases such as arthritis, cancer, and heart disease. Contingency management has been shown to increase physical activity. Therefore, the present study sought to evaluate the effects of an escalating schedule of monetary reinforcement with a reset contingency on physical activity, as compared between 2 counterbalanced groups in which a monetary deposit of $25 was either required (deposit group) or not (no-deposit group). Twenty-five adults wore Fitbit accelerometers to monitor step counts. An ABA reversal design was used; in the 2 baseline phases, no programmed contingencies were in place for step counts. During intervention, step goals were set using a modified 70th percentile schedule with a 7-day window: Reaching the first goal would result in $0.25, and incentives increased by $0.25 for each subsequent day in which the goal was met. Failure to reach a goal resulted in a reset of the monetary incentive value to $0.25. Ten out of 12 participants from the deposit group were determined to be responders to intervention, whereas 8 out of 13 participants from the no-deposit group were determined to be responders to intervention. Overall, there were no significant differences between the groups' step counts. However, the deposit group's intervention was cheaper to implement, which suggests that deposit contracts are a viable modification for physical activity interventions.  相似文献   
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