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981.
Four boys and 4 girls (3 to 5 years old) played with as many as three toys chosen from a set of six, and were then asked whether they played with each of the toys. After a baseline in which all children showed high levels of correspondence between reported and actual behavior, reports of play were differentially reinforced, first in an individual and then in a social context. Two children in the individual condition began to report play with all six toys, even though no more than three toys had been played with. When reports of play were reinforced in a group context, 5 children reported play with all six toys. When correspondence was subsequently reinforced, virtually complete correspondence returned and was maintained in a third noncontingent reinforcement condition. Correspondence and lack of correspondence were discussed in terms of self-tacting and distorted tacting or manding.  相似文献   
982.
With the aim of assessing four forms of therapy with adjustment-disordered outpatients, we randomly assigned 70 subjects to the following treatments: supportive psychotherapy (psychoanalytically oriented), viloxazine (an antidepressant), lormetazepam (a benzodiazepine), and S-adenosylmethionine (a methyl donor with antidepressive properties). A further group of 15 subjects received a placebo, orally administered. The trial lasted 4 wk. None of the treatments had clearly superior effects over others on scores on the Zung Self-rating Depression Scale. All produced a significant improvement. However, groups given S-adenosylmethionine and supportive psychotherapy had the highest mean scores.  相似文献   
983.
In this experiment, which is basically a replication of an earlier experiment done in 1988, we tested the hypothesis that the brain self-regulates its own arousal and activation. When subjects perform a putative right-hemisphere task (visuospatial), the effect of a supplementary information-processing load is supposed to lead to a delayed reaction. The opposite is supposed to be true in a putative left-hemisphere task (semantic). The former effect is supposed to be the result of increased arousal, the latter is that of increased activation. In the present experiment the reactions subject to experimental treatment are compared with control reactions of the same subject. This was not the case in the earlier experiment. Still other improvements of the experimental design were made. The results clearly confirm the earlier findings. Additional evidence is offered to strengthen the plausibility of the basic hypothesis.  相似文献   
984.
Seventeen spontaneous speech measures and scores on a naming test, employed to characterize the expressive performance of 121 aphasics, were subjected to a factor analysis. Five factors were obtained: (1) Syntactic ability, (2) Phonological paraphasia, (3) Neologistic paraphasia, (4) Articulatory impairment, and (5) Vocabulary. Relationships of the factors to naming error types were examined in order to elucidate the nature of some of the factors. Also, the relationships of the expressive factors to auditory comprehension tests were explored, such an exploration being relevant to the issue of the overlap between expressive and receptive functions.  相似文献   
985.
Although several studies have shown that social reprimands can function as punishers, no study reported to date has isolated any of the factors influencing reprimand efficacy. Three experiments were conducted to investigate several factors. Experiment 1 used an alternating treatments design and was conducted on two elementary school boys, one of whom was in a special education class. Results showed that verbal reprimands delivered with eye contact and firm grasp of the student's shoulders reduced disruptive behavior to a greater extent than did verbal reprimands delivered without eye contact and grasp. Both types of reprimand were more effective than a baseline condition during which disruptive behavior was ignored. Experiment 2 also used an alternating treatments design and was conducted on one elementary school boy. Results demonstrated that reprimands delivered from one meter away were considerably more effective than reprimands delivered from seven meters away. Experiment 3 used a reversal design and was conducted on two pairs of elementary school children, one a pair of boys and the other a pair of girls. Results demonstrated that reprimands delivered to just one member of the pair reduced the disruptive behavior of both members of the pair. Thus, the effects of reprimands “spilled” over to nonreprimanded students.  相似文献   
986.
Previous research has demonstrated that a sequence of tones that is alternated between ears is stretched out in echoic memory, as compared with monaural sequences. Although the stimulus onset asynchronies (SOAs) were the same in the interaural and monaural conditions, the perceptual onset asynchronies (POAs) differed by 24 msec. The present study investigated whether an analogous perceptual phenomenon exists for frequency-alternating tone sequences. It turned out that the POAs of coherent and even of streaming tone sequences were precisely the same as with nonalternating tone sequences.  相似文献   
987.
The research reported in this paper was designed to assess the feasibility of using a novel apparatus (a so-called ski-movement simulator) in the study of the acquisition of gross cyclical motor skills and further to develop analytic techniques appropriate to the movements involved. Three such methods are discussed: (1) the mean absolute deviation from the middle position as a measure of the ‘amplitude’ of the movement; (2) an auto-correlation coefficient as a measure of the ‘timing’ of the movement; (3) a cross-correlation coefficient as a measure of the ‘smoothness’ of the movement.Progress in learning - as shown by the measures of amplitude and smoothness- showed the expected trend, in that performance improved throughout the whole of the duration of the experiment (four consecutive days), but the rate of improvement gradually decreased. The largest effects were found for the ‘amplitude’ measure, which had the drawback that the ultimate level of performance was constrained by the body weight of the subject. The ‘smoothness’ measure did not suffer from this disadvantage and its suitability as a measure designed to evaluate gross skill acquisition in a laboratory situation is discussed.The ‘timing’ measure did not follow the same trend and reasons for this finding are proposed. Overall, it would seem that the different measures have varying usefulness in the study of skill acquisition and it is therefore advisable to study them separately.  相似文献   
988.
Olfactory dysfunction in man: anatomical and behavioral aspects   总被引:2,自引:0,他引:2  
We reviewed studies examining the olfaction of patients with brain damage for the purpose of discerning correlations between disordered structure and function. Patient samples included those with neurological disorders and neurosurgical interventions and recording of spontaneous or elicited neuronal activity. Brain areas involved in olfaction include the olfactory bulbs, the orbitofrontal and medial temporal cortices, the thalamus, and the amygdala. Despite recent advances in olfactory anatomy, understanding of how these structures are related to olfactory detection, discrimination, and recognition continues to be limited. Inadequate localization of brain lesions and lack of comprehensive behavioral assessment have thus far prevented a detailed account of the organization of olfaction in the human brain.  相似文献   
989.
An archival study was done of 500 medical records from a community clinic serving a low income predominantly Hispanic area of Los Angeles. The data collected included demographic characteristics and presented symptoms or reasons for visit, as well as diagnosis and treatment. The greatest number of patient visits were made for family planning services. A large porportion of the patients who received initial family planning services failed to return to the clinic for follow ups or additional supplies. A total of 208 pregnancy tests were performed in 151 of the 500 cases sampled. Of these, 152 were positive. The most frequently stated reason for requesting pediatric services was for physical exams, accounting for 30% of the visits. It should be noted that the discontinuity of care and insufficient utilization of preventive care seen in these results deserve serious attention by medical clinic administrators. The rate of patients who do not return for family planning after the initial visit is worrisome. A greater effort to attract women to family planning services at the time they request pregnancy verification could reduce the need for abortion of unwanted pregnancy. The data also indicate that changes in the wording of certain questions commonly asked of clients may be needed. This study allowed service providers to obtain important information about their performance, their needs, and the future direction that their services might take. This type of analysis is relatively low in cost and can yield important benefits, espicially if done on a periodical base in a search for policy implications.  相似文献   
990.
In our recent efforts to understand individual variation in the language acquisition process, the existence and nature of the communicative behaviors that differentiate reticent from talkative children have been virtually ignored. This study provides a preliminary investigation of this issue by analyzing the spontaneous language produced by four children who varied in degree of talkativeness in free-play dyadic interactions with a total of 28 different adults. Both structural complexity and discourse features analyses of the children's language revealed significant, difference between the talkative and reticent children. A further question considered the influence of the children's degree of talkativeness on their adult conversational partners. While the structural complexity of the adults' language was not influenced by child talkativeness, several discourse parameters did reveal significant adjustments. Implications for the concept of reticence and for language acquisition theory are explored.  相似文献   
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