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851.
Gender differences in the perception of medical school stressors, trait anxiety, and the sense of coherence were investigated in a longitudinal study in an Israeli medical school. The overall stressor score increased for both sexes from orientation to the second year of studies. The increase in the stressor score among women was due primarily to their increasing concern about professional status issues; for men, the academic demands factor contributed most to their increased overall stressor score. Trait anxiety increased and the sense of coherence decreased over time for both sexes. The gender difference in anxiety was significant in the first two stages, but disappeared in the third stage, indicating that although men had lower scores at all stages, their scores increased relatively more than women's over time. The findings suggest that the stressors of medical education have a negative effect on two personality resources needed to deal with life's demands.  相似文献   
852.
Children in kindergarten-first grades and fourth-sixth grades (6 and 10 years of age, respectively) participated in one of two experiments and performed either a simple motor task or (for older children only) a two-choice simultaneous discrimination task at two difficulty levels. Children received either positive, negative, or no peer comparison statements (describing how other children their age had allegedly performed) and either praise, silence (in Experiment 2 only), or criticism on a fixed-interval 20-second schedule throughout the task. Young children were more responsive to adult evaluation of their performance than to peer comparison. Expectancies created by peer comparisons affected older children's motor performance most if they received reinforcement contrary to the expectancy. In situations requiring greater cognitive ability, older children, particularly boys, responded to the performance expectancies created by positive peer comparison. Older boys, compared with older girls, seemed to be more sensitive to peer comparison and social reinforcement.  相似文献   
853.
The study described the abilities of a group of 15 moderately impaired aphasics and 15 normals to produce narrative discourse. The experimental tasks included telling stories, summarizing stories, and giving morals to stories. The data were analyzed in terms of sentential grammar, discourse grammar, and subjective ratings of content and clarity of language. The results showed that aphasics produced well-structured discourse. The language of the aphasics' discourse was reduced in both complexity and amount, as compared to that produced by normals. The reduction of language reflected selective reduction of hierarchically organized information. The findings of the study confirm the results of previous research on mildly impaired aphasics, which also showed preservation of discourse structure with selective reduction of information.  相似文献   
854.
A procedure for catheterizing the external iliac artery in nonhuman primates is described. This preparation can be used both for collecting blood samples and for infusing drugs. The preparation is well suited to long-term studies. Our experience indicates that, with appropriate maintenance, these catheters may remain patent for intervals of approximately 12 months.  相似文献   
855.
856.
Pigeons were trained on a multiple schedule in which the duration of access to grain reinforcement was varied independently in the two components. The relative response rate in one component was an increasing function of the relative duration of reinforcement in that component. The similarity of this interaction to that found in multiple schedules of different reinforcement frequency is discussed. Extinction data were also similar to those obtained after training on multiple schedules of different reinforcement frequency.  相似文献   
857.
Although many factors have been proposed and studied as causes of onset and termination of meals by humans, little attention has been paid to memory for what has previously been eaten. We propose that a principal determinant of meal onset and cessation in humans is memory of when a last meal was eaten and how much was consumed. Knowledge that one has just eaten a culturally defined complete meal may be sufficient grounds for refusal of further food. This hypothesis was tested by studying two densely amnesic patients who had almost no explicit memory for events that occurred more than a minute ago, and who, in particular, usually failed to remember that they had just eaten a meal. Both patients (on three occasions each) readily consumed a second lunch when it was offered 10 to 30 min after completion of the first meal, and usually began to consume a third meal when it was offered 10 to 30 min after completion of the second meal. These findings suggest that memory for what has recently been eaten is a substantial contributor to the onset or cessation of eating of a meal.  相似文献   
858.
The increased use of bone marrow transplantation (BMT) to treat a variety of cancers has led researchers to study psychological functioning of BMT patients. The majority of studies conducted, however, has focused on adjustment after transplantation. Cancer patients' use of coping strategies before undergoing this procedure may also relate to levels of psychological distress. Our aims were (1) to provide normative coping data, controlling for situation-specific variables with a homogeneous sample, targeted stressor, and fixed time point, using the Ways of Coping Questionnaire; and (2) to identify coping strategies associated with distress before high-dose chemotherapy. Subjects were 49 patients scheduled to receive high-dose chemotherapy and an autologous bone marrow transplant. Consistent with previous coping research, we found that escape-avoidance was related to psychological distress on several measures. Item endorsement analyses of the escape-avoidance subscale suggest that patients may have used more passive than active avoidance strategies. Subsequent participation in a longitudinal study was not affected by initial levels of avoidant coping.  相似文献   
859.
Thirty-two female undergraduates were presented with varied, mildly stressful incentives while the temperatures of their face and hands were recorded with infrared telethermography. There was an increase of hand skin temperature to film clips intended to generate a happy affect but cooling to threatening personal questions. There was no significant skin temperature change in response to cognitive tasks or fear eliciting film clips. Larger temperature changes occurred on the hands than on the face, and most subjects were cooler on the left side of the face and the left hand than on the right side of face and right hand.  相似文献   
860.
Golden hamsters received free shock (Experiment 1) or they were partially (Experiments 2 and 3) or continuously (Experiments 4 and 5) punished with mild electric shock for face washing, open rearing, or scrabbling. Punishment immediately and enduringly reduced the time engaged in scrabbling and the number and length of its bouts. Face washing was also clearly associated with shock, since effects specific to the contingency between face washing and shock were retained when shock was discontinued, but under some conditions punishment increased the number of bouts of face washing. Open rearing was the most refractory of the three activities to suppression and showed least evidence of retaining the effects of punishment. This pattern of results differs from that found previously when food reinforcement was given for the same activities. It is discussed in terms of constraints on performance of learned associations by a variety of response-specific and reinforcer-specific motivational factors.  相似文献   
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