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91.
Austin PC 《Multivariate behavioral research》2011,46(1):119-151
Propensity score methods allow investigators to estimate causal treatment effects using observational or nonrandomized data. In this article we provide a practical illustration of the appropriate steps in conducting propensity score analyses. For illustrative purposes, we use a sample of current smokers who were discharged alive after being hospitalized with a diagnosis of acute myocardial infarction. The exposure of interest was receipt of smoking cessation counseling prior to hospital discharge and the outcome was mortality with 3 years of hospital discharge. We illustrate the following concepts: first, how to specify the propensity score model; second, how to match treated and untreated participants on the propensity score; third, how to compare the similarity of baseline characteristics between treated and untreated participants after stratifying on the propensity score, in a sample matched on the propensity score, or in a sample weighted by the inverse probability of treatment; fourth, how to estimate the effect of treatment on outcomes when using propensity score matching, stratification on the propensity score, inverse probability of treatment weighting using the propensity score, or covariate adjustment using the propensity score. Finally, we compare the results of the propensity score analyses with those obtained using conventional regression adjustment. 相似文献
92.
Previous research has shown that rats can learn matching-to-sample relations with olfactory stimuli; however, the specific characteristics of this relational control are unclear. In Experiment 1, 6 rats were trained to either match or nonmatch to sample in a modified operant chamber using common household spices as olfactory stimuli. After matching or nonmatching training with 10 exemplars, the contingencies were reversed with five new stimuli such that subjects trained on matching were shifted to nonmatching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new exemplars. In Experiment 2, 9 rats were trained with matching procedures in an arena that provided for 18 different spatial locations for comparison stimuli. Five subjects were trained with differential reinforcement outcomes and 4 with only one type of reinforcer. Differential outcomes and multiple exemplars facilitated learning, and there was strong evidence for generalization to new stimuli for most rats that acquired several conditional discriminations. Performances with novel samples were generally above chance, but rarely reached the high levels obtained during baseline with well-trained stimulus relations. However, taken together, the data from the two experiments extend previous work, show that rats can learn both match and nonmatch relations with different experimental protocols, and demonstrate generalization to novel sample stimuli. 相似文献
93.
Despite evidence towards the risk for discrimination and acculturative stress that Arab American adolescents may face, the link between socio-cultural adversities and psychological well-being in this population has not been established. This study examined the role of socio-cultural adversities (discrimination and acculturative stress) and cultural resources (ethnic identity, religious support and religious coping) in terms of their direct impact on psychological distress. Using structural equation modeling, the proposed model was tested with 240 Arab American adolescents. The results indicated a strong positive relationship between socio-cultural adversities and psychological distress. Furthermore, this study supported a promotive model of cultural resources, where a negative association between cultural resources and psychological distress was found. Understanding the manner in which socio-cultural adversities and resources are linked to psychological distress can inform the development of culturally appropriate interventions that can effectively mitigate mental health concerns for understudied and vulnerable populations. 相似文献
94.
Michelle M. Martel Molly Nikolas Katherine Jernigan Karen Friderici Irwin Waldman Joel T. Nigg 《Journal of abnormal child psychology》2011,39(1):1-10
Attention-Deficit/Hyperactivity Disorder (ADHD) is a prime candidate for exploration of gene-by-environment interaction (i.e.,
G x E), particularly in relation to dopamine system genes, due to strong evidence that dopamine systems are dysregulated in
the disorder. Using a G x E design, we examined whether the DRD4 promoter 120-bp tandem repeat polymorphism, previously associated with ADHD, moderated the effects of inconsistent parenting
and marital conflict on ADHD or Oppositional-Defiant Disorder (ODD). Participants were 548 children with ADHD and non-ADHD
comparison children and their parents. Homozygosity for the DRD4 promoter 120-bp tandem repeat insertion allele increased vulnerability for ADHD and ODD only in the presence of inconsistent
parenting and appeared to increase susceptibility to the influence of increased child self-blame for marital conflict on ADHD
inattention. DRD4 genotypes may interact with these proximal family environmental risk factors by increasing the individual’s responsivity
to environmental contingencies. 相似文献
95.
Psychopathy is a robust predictor of overt physical aggression that may also be relevant to relational aggression (RA). This study was conducted to investigate the utility of psychopathic personality traits in the prediction of RA in a sample of 291 college students. Hierarchical multiple regression analyses indicated that both primary and secondary psychopathic traits explained additional variance in general/peer and romantic RA beyond physical aggressiveness. Consistent with previous research, no gender differences were found on either form of RA, challenging the popular stereotype of RA as a female behavior. Moreover, psychopathic traits were not differentially predictive of RA by gender or level of physical aggressiveness. Implications of these findings for research and clinical practice are discussed. 相似文献
96.
Subašić E Schmitt MT Reynolds KJ 《The British journal of social psychology / the British Psychological Society》2011,50(4):707-725
Common experience of injustice can be a potent motivator of collective action and efforts to achieve social change - and of such efforts becoming more widespread. In this research, we propose that the effects of co-victimization on collective action are a function of inclusive social identity. Experiment 1 (N= 61) demonstrated that while presence (compared to absence) of co-victimization positively predicted consumer (i.e., participants) willingness to act collectively in solidarity with sweatshop workers, this effect was mediated by inclusive social identity. In Experiment 2 (N= 120), the salience of inclusive social identity was experimentally manipulated and interacted with co-victimization to predict collective action. When inclusive social identity was salient, co-victimization enhanced collective action, including willingness to pay extra for products made ethically and in support of fair wages for workers. In contrast, collective action was attenuated when co-victimization took place in the absence of inclusive social identity. Implications for understanding when co-victimization is transformed into common fate and political solidarity with the disadvantaged are discussed. 相似文献
97.
Timothy Z. Keith Matthew R. ReynoldsLisa G. Roberts Amanda L. WinterCynthia A. Austin 《Intelligence》2011,39(5):389
Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these differences across age. Most broad abilities showed mean differences across the sexes, and all such differences varied across ages. Girls showed an advantage on the processing speed (Gs) first-order residual factor. Girls also showed advantages at some ages on free-recall memory, a narrow ability of long term retrieval (Glr). Boys showed a developmentally-related advantage on a visual-spatial ability (Gv) first-order residual factor, depending on age. Younger girls showed an advantage on short-term memory (Gsm). No statistically significant sex differences were shown on the latent comprehension-knowledge (Gc) factor, or on a second-order, latent g factor. Boys showed larger variances for several broad abilities, some substantial, but those differences were not statistically significant. 相似文献
98.
Kimberly Cuevas Kirby Deater‐Deckard Jungmeen Kim‐Spoon Amanda J. Watson Katherine C. Morasch Martha Ann Bell 《Developmental science》2014,17(2):224-238
Executive functions (EFs; e.g. working memory, inhibitory control) are mediated by the prefrontal cortex and associated with optimal cognitive and socio‐emotional development. This study provides the first concurrent analysis of the relative contributions of maternal EF and caregiving to child EF. A group of children and their mothers (n = 62) completed age‐appropriate interaction (10, 24, 36 months) and EF tasks (child: 24, 36, and 48 months). Regression analyses revealed that by 36 months of age, maternal EF and negative caregiving behaviors accounted for unique variance in child EF, above and beyond maternal education and child verbal ability. These findings were confirmed when using an early child EF composite‐our most reliable measure of EF – and a similar pattern was found when controlling for stability in child EF. Furthermore, there was evidence that maternal EF had significant indirect effects on changes in child EF through maternal caregiving. At 24 months, EF was associated with maternal EF, but not negative caregiving behaviors. Taken together, these findings suggest that links between negative caregiving and child EF are increasingly manifested during early childhood. Although maternal EF and negative caregiving are related, they provide unique information about the development of child EF. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=NPKXFbbrkps 相似文献
99.
100.
Espelage Dorothy L. Valido Alberto Robinson Luz E. Ingram Katherine M. El Sheikh America Woolweaver Ashley M. Koritz Laura Vincent Claudia G. Marquez Brion Walker Hill M. Svanks Rita Marmolejos Roslyn Reynoso Medina Courtney Meltsner Zeke Yalamanchi Kovida Pennefather Jordan 《Social Psychology of Education》2022,25(5):1177-1203
Social Psychology of Education - Creating effective school-wide safety mechanisms depends on understanding students' previous experiences of reporting, however, students may also be... 相似文献