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191.
The effects of irradiation on twin boundary migration in BCC Fe are studied by atomistic simulations. It is found that under the applied shear strain–stress, thermal spikes may create twinning dislocation loops (TDLs) at twin boundaries, so triggering twinning. Irradiation-generated clusters of point defect at twin boundaries may act as sources to nucleate TDLs. When a vacancy loop intersects with a twin boundary, the critical stress to activate a TDL is less than half of that required for a defect-free twin boundary. 相似文献
192.
Cognitive control is essential to flexible, goal-directed behavior under uncertainty, yet its underlying mechanisms are not clearly understood. Because attentional functions are known to allocate mental resources and prioritize the information to be processed, we propose that the attentional functions of alerting, orienting, and executive control and the interactions among them contribute to cognitive control in the service of uncertainty reduction. To test this hypothesis, we examined the relationship between cognitive control and attentional functions. We used the Majority Function Task (MFT) to manipulate uncertainty in order to evoke cognitive control along with the Revised Attention Network Test (ANT-R) to measure the efficiency and the interactions of attentional functions. A backwards, stepwise regression model revealed that performance on the MFT could be significantly predicted by attentional functions and their interactions as measured by the ANT-R. These results provide preliminary support for our theory that the attentional functions are involved in the implementation of cognitive control as required to reduce uncertainty, though further investigation is needed. 相似文献
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Subin Park Min-Hyeon Park Hyo Jin Kim Hee Jeong Yoo 《Journal of child and family studies》2013,22(4):559-568
The objective of this study was to examine (a) anxiety and depression symptoms in children with Asperger syndrome (AS) compared to children with attention-deficit/hyperactivity disorder (ADHD) and children with depressive disorder; (b) parental anxiety and depressive symptoms in the three groups; and (c) the association between the anxiety and depression symptoms of children and their parents. The emotional and behavioral problems of 56 children with AS (48 boys, 8 girls, mean age, 9.39 ± 2.01 years) were compared with 56 ADHD children and 56 depressive disorder children, matched for age and sex. Their parents’ anxiety and depression symptoms were also compared. Trait-anxiety and internalizing problems in AS children were higher than those in ADHD children and as high as those in depressive disorder children (F = 8.83, p < 0.001 and F = 8.21, p < 0.001). Parents’ anxiety and depression symptoms did not differ among the three groups, but correlations between maternal anxiety and depression and children’s emotional and behavioral problems were most prominent in the AS group. We suggest that the assessment and treatment of children with AS should involve detailed assessment, possible concomitant treatment for comorbid anxiety and depression, and parental education about the effect of parental emotional states on children. 相似文献
195.
郑进 《医学与哲学(人文社会医学版)》2013,34(14):89-91
救护车车载物品是院前急救的基础和保障,对院前急救的效率和质量具有十分重要的意义.本文总结并分析了美国救护车车载物品和院前急救的特点:更加注重院前急救人员的个人防护;更加注重对患者的救出;更加注重心脏按压板的运用;更加注重急救箱物品配置的科学性;更加注重对普通物品的利用;更加注重患者的转运.美国西雅图20世纪70年代抢救5 120例院外猝死患者,复苏成功至康复出院者达28.9%;我国上海医疗救护中心1999年抢救猝死患者4 374名,复苏成功率1.35%.我国院前抢救猝死的成功率明显低于美国,或与中美救护车车载物品的不同相关.了解美国救护车车载物品的特点,对我国的院前急救或有借鉴作用. 相似文献
196.
To examine the reciprocal relations between teacher–child relationships and children's behavior problems, the authors analyzed cross-lagged longitudinal data on teacher–child relationships and children's internalizing and externalizing problems using a structural equation modeling approach. The homeroom teachers of 105 first-year preschoolers aged 2–3 years filled in the Student–Teacher Relationship Scale and the Child Behavior Checklist/2–3, first at 3 months after the children's preschool entrance and then at the end of the first preschool year. Results showed significant cross-wave reciprocal relations between externalizing problems and teacher–child conflict and significant cross-wave relation from early internalizing problems to later teacher–child conflict. However, the cross-wave associations between internalizing and externalizing problems and teacher–child closeness were not significant. 相似文献
197.
Using data from an original two‐wave panel survey of California high school students and a two‐wave panel survey of high school students in Chicago, we find that different pedagogical approaches influence different forms of civic and political engagement. Specifically, controlling for prior levels of engagement and demographic factors, we find that open discussion of societal issues promotes engagement with political issues and elections. In contrast, service learning opportunities increase community‐based and expressive actions. Both kinds of opportunities promoted commitments to participatory citizenship. These patterns can teach us about the kinds of opportunities (both in school and out) that can shape adolescents' civic and political development. 相似文献
198.
David M. Sobel Jin Li Kathleen H. Corriveau 《Journal of cognition and development》2013,14(3):345-369
Two studies examined how 3–6-year-olds understand the process of learning. In study 1 examined how children spontaneously talk about learning via a CHILDES language analysis. Talk about the learning process increased between the ages of 3–5. Talk specifically about learning in terms of desire decreased during this period. This suggests the possibility that desire is important to children's initial understanding of learning, and children develop an understanding that various mental states including desire, attention, and intention, play a role in the learning process. In Study 2, we presented 4- and 6-year-olds with a set of stories designed to test their understanding of the role of these mental states. In both their judgments about whether someone learns and their justifications of their responses, younger children relied more on the character's desires whereas older children were more likely to integrate desire, attention, and intention together. These data suggest that children's understanding of the process of learning is developing during the early elementary school years. 相似文献
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