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101.
Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders.  相似文献   
102.
Objective: To examine components of family-centered care in families' stories about treatment decision making for their child with ADHD. Method: Twenty-eight families participated in qualitative interviews that addressed families' perspectives on (a) the treatment decision-making process, (b) the cause and impact of their child's symptoms, and (c) treatment goals and preferences. Results: The majority of families preferred to be primary or shared decision makers regarding treatment decisions. Families' perspectives on the cause of the child's symptoms varied and often were not consistent with a biomedical framework. Families described multiple areas of impairment on child, family relationships, and family functioning. Perspectives toward evidence-based treatments were mixed, with families also expressing interest in and pursuing interventions not delineated in current treatment guidelines. Conclusion: These findings reinforce the importance of eliciting families' perspectives and involving these important stakeholders in shared decision making as critical components of family-centered care for children with ADHD.  相似文献   
103.
The reform of the tarification according to activity is now in place with a "T2A" rate said to be 100%, ie the hospitals are paid based on the national tariffs for a stay in hospital. The reform will continue with a list of stays for which, each year, a single tariff between the public sector and the private sector is applied. This single tariff results from the "inter-sector tariff convergence" policy which is applied.  相似文献   
104.
The ability to discriminate between quantities has been observed in many species. Typically, when an animal is given a choice between two sets of food, accurate performance (i.e., choosing the larger amount) decreases as the ratio between two quantities increases. A recent study reported that elephants did not exhibit ratio effects, suggesting that elephants may process quantitative information in a qualitatively different way from all other nonhuman species that have been tested (Irie-Sugimoto et al. in Anim Cogn 12:193-199, 2009). However, the results of this study were confounded by several methodological issues. We tested two African elephants (Loxodonta africana) to more thoroughly investigate relative quantity judgment in this species. In contrast to the previous study, we found evidence of ratio effects for visible and nonvisible sequentially presented sets of food. Thus, elephants appear to represent and compare quantities in much the same way as other species, including humans when they are prevented from counting. Performance supports an accumulator model in which quantities are represented as analog magnitudes. Furthermore, we found no effect of absolute magnitude on performance, providing support against an object-file model explanation of quantity judgment.  相似文献   
105.
ObjectivesThe purpose of this study was to examine the effects of different scoring protocols used with instruments designed to assess motivation in line with Organismic Integration Theory (OIT; Deci & Ryan, 2002).DesignThis study used non-probability based sampling within a cross-sectional (survey) design.MethodsParticipants across four samples (N's ranged from 236 to 1200) completed either (a) the Behavioral Regulation in Exercise Questionnaire (BREQ), (b) the BREQ-2, or (c) the BREQ-2R in conjunction with a self-report assessment of physical activity behavior.ResultsParticipants endorsed more self-determined than controlled motives for physical activity. Identified regulation was the dominant correlate of more frequent physical activity behavior. The link between external regulation and physical activity was consistently weak. Multiple regression analyses revealed identified regulation was the strongest predictor of physical activity compared with other motives. Regression models using omnibus scoring protocols accounted for less variance in physical activity behavior in contrast to an item-aggregation scoring protocol.ConclusionsIdentified regulation may be a key source of physical activity motivation in adults. The scoring protocol used with OIT-based instruments represents an important consideration for advancing physical activity research.  相似文献   
106.
ObjectivesThis study examined youth ice hockey players' perceptions of individual feedback received from their coach, and the agreement and discrepancies between preferred and perceived coach feedback patterns, on athletes' perceptions of team motivational climate. The following research questions were answered: How does agreement in perceived and preferred coach feedback relate to task- and ego-involving motivational climate? How does the degree of discrepancy between perceived and preferred coach feedback relate to motivational climate? How does the direction of the discrepancy between perceived and preferred coach feedback relate to motivational climate?DesignThis study used non-probability based sampling within a cross-sectional (survey) design.MethodAthletes (n = 70) completed a self-report survey comprised of measures of coaching feedback and motivational climate. The data were examined using polynomial regression and response surface analysis.ResultsLinear associations were observed between coaching feedback and motivational climate, and unique associations between the perceived and preferred coach feedback discrepancies were distinctly related to increased perceptions of both task- and ego-involved motivational climates.ConclusionsThe type of feedback, purpose of the feedback, and agreement or discrepancy in perceptions and preferences for different feedback styles are important to understanding task- and ego-involved motivational climate in youth sport. Coaching programs should assist coaches in learning their athletes' preferences for positive and negative feedback in sport and matching these preferences with their individual feedback styles.  相似文献   
107.
A smile may communicate different communicative intentions depending on subtle characteristics of the facial expression. In this article, we propose an algorithm to determine the morphological and dynamic characteristics of virtual agent's smiles of amusement, politeness, and embarrassment. The algorithm has been defined based on a virtual agent's smiles corpus constructed by users and analyzed with a decision tree classification technique. An evaluation, in different contexts, of the resulting smiles has enabled us to validate the proposed algorithm.  相似文献   
108.
Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants.  相似文献   
109.
Although cognitive-behavioral treatments for schizophrenia and other psychotic disorders demonstrate strong results in clinical trials, not all patients respond to these treatments. Common challenges in psychotherapy with delusional patients include a mismatch between the therapist’s and the patient’s expectations about the purpose of therapy, the patient’s lack of motivation to reduce delusional beliefs in service of other goals, and the patient’s dependence on the delusions in order to preserve an intact sense of self. This case highlights the value of integrating a psychodynamic perspective with cognitive-behavioral interventions to address challenges in psychotherapy with chronically delusional patients.  相似文献   
110.
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