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991.
Laboratory rats were used to investigate sex and strain differences in the effects of aggression on a cooperative behavior in which pairs learn to coordinate shuttling in a rectangular chamber. The level of aggression was manipulated by comparing males and females of the aggressive S3 strain and a less aggressive Sprague-Dawley-derived strain and by housing same-sex partners either together or individually (eight groups, n = 7 pairs per group). Hormone levels were stabilized by gonadectomy and daily injections of the appropriate sex hormone. The only serious coordination deficits were in individually housed males, associated with violent fighting and an extreme dominance/subordinance relationship that was not observed in females. All other groups readily learned and performed the coordination, with evidence that low and moderate levels of aggression could facilitate coordination by evoking species-typical behaviors that increased proximity, synchrony, and differentiation within pairs. The discussion focused on models of affiliative behavior in the study of aggression and the compatibility between moderate levels of aggression and cooperation. 相似文献
992.
The Brazelton Neonatal Behavioral Assessment Scale is the most widely used and accepted tool in the study of the behavior of the human newborn; yet there remains some controversy over the most appropriate way to score the results. The present research compares three a priori methods of scoring. The sample consisted of 43 infants: (a) 11 preterms, (b) 10 fullterms in intensive care, (c) 7 fullterms with sick mothers, and (d) 15 healthy fullterms. BNBAS exams administered to these four groups of infants were scored using the Als (1978), Lester, Als, and Brazelton (1982), and Jacobsen, Fein, Jacobsen, and Schwartz (1984) clusters. The data from these three methods were analyzed by means of one-way ANOVAs for group differences. In addition, a factor analysis on the BNBAS scores was also completed. These three approaches all detected differences between medically at-risk and healthy infants on those items assessing motor maturity and orientation. These results suggest that at this time no one scoring system can capture the richness of behavior of the newborn and address the question by researchers, clinicians, and parents. 相似文献
993.
994.
Male rats were either handled daily or left undisturbed (nonhandled) during the first 21 days of life. At weaning (Day 22) animals in each early treatment condition were assigned to two housing conditions, isolated or grouped, creating four early/late treatment conditions: Handled-Grouped (HG), Handled-Isolated (HI), Nonhandled-Grouped (NHG), and Nonhandled-Isolated (NHI). At maturity, all animals were tested in the latent inhibition (LI, Experiment 1) and the partial reinforcement extinction effect (PREE, Experiment 2) paradigms. In LI, animals receiving prior nonreinforced preexposure to a stimulus (PE) show subsequently retarded conditioning to that stimulus as compared to nonpreexposed (NPE) controls. In the PREE, partially reinforced (PRF) animals exhibit higher resistance to extinction as compared to continuously reinforced (CRF) controls. LI and PREE were obtained in the HG condition, but were impaired in NHG and HI animals. The pattern of impairment was different in the two conditions. The absence of LI in NHG males was due to increased suppression in the PE group, whereas in HI males, was due to decreased suppression in the NPE group. Likewise, the attenuation of the PREE in NHG males stemmed primarily from decreased resistance to extinction in the PRF group, whereas in HI males, it resulted from increased resistance to extinction in the CRF group. The combination of nonhandling and isolation led to the reinstatement of both LI and PREE: normal LI and PREE were obtained in the NHI animals. These results demonstrate that early rearing experience interacts with later experience differentially depending upon the later experience. 相似文献
995.
Richard A. Winett Eileen S. Anderson Laurie L. Desiderato Laura J. Solomon Melissa Perry Jeffrey A. Kelly Kathleen J. Sikkema Roger A. Roffman Ann D. Norman David N. Lombard Tamara N. Lombard 《Applied and Preventive Psychology》1995,4(4):233-245
Social diffusion theory has recently been recognized as a promising approach for large-scale disease prevention and health promotion efforts. This paper describes how principles and tactics from social cognitive theory, operant psychology, social psychology, social marketing, and the overarching stages of change model can be used to further develop the conceptual and strategic (technological) bases of social diffusion theory. Within an integrative framework, we discuss in detail more effective ways to train peer mediators of behavior change as one example of how social diffusion theory can benefit from this conceptual and strategic reformulation. We then further illustrate the use of peer mediators of change in human immunodeficiency virus (HIV) and cancer prevention intervention studies with both interventions training peer mediators to diffuse information, norms, and risk reduction strategies. Although the results of these studies showed reductions in high-risk behaviors across population segments, more closely following the framework discussed in this article should further increase the behavior change potential of future interventions based on social diffusion theory. 相似文献
996.
Rats with cannulas aimed at the posteroventral (PV) or ventrolateral (VL) areas of the caudate nucleus were trained on a conditioned emotional response (CER) task. Post-training microinjections of the indirect catecholamine agonist, d-amphetamine (5 micrograms), or of the dopamine D2 receptor agonist, LY171555 (1 microgram), into the PV area improved retention of a CER with a visual CS, but had no effect on a CER with an olfactory CS. Post-training injections of the same two drugs into the VL area improved retention of a CER with an olfactory CS, but had no effect on a CER with a visual CS. Post-training injections of the dopamine D1 receptor agonist, SKF38393 (0.5, 1.0, 2.0 micrograms), into either site had no effects on either CER. These findings suggest that different areas of the caudate nucleus mediate acquisition of CERs with different CSs, possibly implicating the topographically organized corticostriatal innervation in the acquisition of certain types of memories in the caudate nucleus. The findings also suggest that dopamine D2 receptors in the caudate nucleus are involved in the acquisition of these CERs. 相似文献
997.
Selina N. Emhardt Ellen M. Kok Halszka Jarodzka Saskia Brand-Gruwel Christian Drumm Tamara van Gog 《Cognitive Science》2020,44(9):e12893
Domain experts regularly teach novice students how to perform a task. This often requires them to adjust their behavior to the less knowledgeable audience and, hence, to behave in a more didactic manner. Eye movement modeling examples (EMMEs) are a contemporary educational tool for displaying experts’ (natural or didactic) problem-solving behavior as well as their eye movements to learners. While research on expert-novice communication mainly focused on experts’ changes in explicit, verbal communication behavior, it is as yet unclear whether and how exactly experts adjust their nonverbal behavior. This study first investigated whether and how experts change their eye movements and mouse clicks (that are displayed in EMMEs) when they perform a task naturally versus teach a task didactically. Programming experts and novices initially debugged short computer codes in a natural manner. We first characterized experts’ natural problem-solving behavior by contrasting it with that of novices. Then, we explored the changes in experts’ behavior when being subsequently instructed to model their task solution didactically. Experts became more similar to novices on measures associated with experts’ automatized processes (i.e., shorter fixation durations, fewer transitions between code and output per click on the run button when behaving didactically). This adaptation might make it easier for novices to follow or imitate the expert behavior. In contrast, experts became less similar to novices for measures associated with more strategic behavior (i.e., code reading linearity, clicks on run button) when behaving didactically. 相似文献
998.
Attention-Deficit/Hyperactivity Disorder (ADHD) is related to suboptimal decision making in experimental tasks and to real-life risk-taking behavior (RTB) such as substance abuse and unsafe traffic conduct. In this preregistered study, we tested whether these associations are mediated by need for cognition—the extent to which one tends towards, and enjoys, analytical thought. In a large sample of young adults (N = 463, Mage = 19.7 years), we tested whether need for cognition mediated the association between self-reported ADHD symptoms on the one hand and decision-making strategy complexity on an experimental gambling task and self-reported real-life RTB on the other hand. Preregistered confirmatory analyses indicated first that ADHD symptoms were positively associated with real-life RTB, but the association was not mediated by need for cognition. Second, ADHD symptoms were not related to decision-making strategy complexity, and need for cognition was not a significant mediator. Explorative analyses revealed that (a) need for cognition was associated with higher decision-making accuracy and slower reaction time; (b) need for cognition was related to inattentive but not to hyperactive/impulsive ADHD symptoms; (c) need for cognition was associated with health-related RTB but not interpersonal RTB; and (4) only the association between inattention and health-related RTB was mediated by need for cognition. We conclude that need for cognition is not a mediator in the association between ADHD symptoms and RTB. Additionally, we conclude that neither ADHD symptoms nor need for cognition predict decision-making strategy complexity. Implications for both future research and clinical practice are discussed. 相似文献
999.
Allison M. Tackman Erica N. Baranski Alexander F. Danvers David A. Sbarra Charles L. Raison Suzanne A. Moseley Angelina J. Polsinelli Matthias R. Mehl 《欧洲人格杂志》2020,34(5):753-776
Past research using the Electronically Activated Recorder (EAR), an observational ambulatory assessment method for the real-world measurement of daily behaviour, has identified several behavioural manifestations of the Big Five domains in a small college sample (N = 96). With the use of a larger and more diverse sample of pooled data from N = 462 participants from a total of four community samples who wore the EAR from 2 to 6 days, the primary purpose of the present study was to obtain more precise and generalizable effect estimates of the Big Five–behaviour relationships and to re-examine the degree to which these relationships are gender specific. In an extension of the original article, the secondary purpose of the present study was to examine if the Big Five–behaviour relationships differed across two facets of each Big Five domain. Overall, while several of the behavioural manifestations of the Big Five were generally consistent with the trait definitions (replicating some findings from the original article), we found little evidence of gender differences (not replicating a basic finding from the original article). Unique to the present study, the Big Five–behaviour relationships were not always comparable across the two facets of each Big Five domain. © 2020 European Association of Personality Psychology 相似文献
1000.
Christoph N. Herde Filip Lievens Duncan J. R. Jackson Ali Shalfrooshan Philip L. Roth 《International Journal of Selection & Assessment》2020,28(1):45-54
To promote diversity in organizations it is important to have accurate knowledge about subgroup differences associated with selection procedures. However, current estimates of subgroup differences in situational judgment tests (SJTs) are overwhelmingly based on range‐restricted incumbent samples that are downwardly biased. This study provides much‐needed applicant level estimates of SJT subgroup differences (N = 37,530). As a key finding, Black‐White differences (d = 0.66) were higher than in incumbent samples (d = 0.38). Overall, sex differences were small. Females scored higher for management jobs (d = ?0.13) and males scored higher for administrative jobs (d = 0.15). By analyzing applicant samples that do not suffer from range restriction, this study adds knowledge about subgroup differences in SJTs. 相似文献