全文获取类型
收费全文 | 6326篇 |
免费 | 297篇 |
出版年
2023年 | 50篇 |
2022年 | 50篇 |
2021年 | 99篇 |
2020年 | 105篇 |
2019年 | 154篇 |
2018年 | 216篇 |
2017年 | 201篇 |
2016年 | 253篇 |
2015年 | 170篇 |
2014年 | 202篇 |
2013年 | 769篇 |
2012年 | 311篇 |
2011年 | 349篇 |
2010年 | 204篇 |
2009年 | 199篇 |
2008年 | 302篇 |
2007年 | 254篇 |
2006年 | 221篇 |
2005年 | 197篇 |
2004年 | 195篇 |
2003年 | 203篇 |
2002年 | 169篇 |
2001年 | 111篇 |
2000年 | 119篇 |
1999年 | 90篇 |
1998年 | 81篇 |
1997年 | 72篇 |
1996年 | 49篇 |
1995年 | 45篇 |
1994年 | 56篇 |
1993年 | 31篇 |
1992年 | 67篇 |
1991年 | 49篇 |
1990年 | 72篇 |
1989年 | 66篇 |
1988年 | 62篇 |
1987年 | 43篇 |
1986年 | 54篇 |
1985年 | 59篇 |
1984年 | 54篇 |
1983年 | 41篇 |
1982年 | 48篇 |
1981年 | 40篇 |
1980年 | 33篇 |
1979年 | 49篇 |
1978年 | 30篇 |
1977年 | 27篇 |
1975年 | 22篇 |
1974年 | 20篇 |
1966年 | 20篇 |
排序方式: 共有6623条查询结果,搜索用时 15 毫秒
951.
Jolien van der Geugten Berno van Meijel Marion H. G. den Uyl Nanne K. de Vries 《Sexuality & culture》2017,21(4):1040-1061
The youth in Bolgatanga municipality in Ghana have relatively less knowledge of sexual and reproductive health (SRH) compared to the youth in other parts of Ghana. More fundamental knowledge is needed of the factors that influence young people to have protected and unprotected sex in specific social and cultural contexts, in order to protect them from adverse consequences, such as sexually transmitted diseases (STIs), HIV/AIDS and unintended pregnancies. This study therefore analyzed the conceptions and attitudes of the youth toward protected and unprotected sex, and particularly condom use, in Bolgatanga municipality. Semi-structured and focus group interviews were held with 71 young males and females and 17 adults. The results indicated that many of them lack a comprehensive knowledge of STIs, contraceptives and pregnancy, while a group of them had a negative attitude towards contraceptives. Not all parents, schools and organisations provide young people with a comprehensive education about SRH, and some even discourage such education because they believe it would encourage young people to have sex before marriage. In addition, young people also inform each other about SRH issues, sharing stories and personal experiences with their peers. The information they exchange is not always correct, however; sometimes it merely reflects their own personal preferences. The unequal power in the sexual relationships of young people—related to the traditional value system that gives men, but not women, “sexual freedom, both in and outside marriage”—is another determining factor for unprotected sex. 相似文献
952.
The aim of this study was to profile the psychological coping, learning potential and career-related interests of 251 candidates for operational force military selection for the South African National Defence Force (SANDF) – 26 of whom were successful in the selection. Data on their sense of meaning, learning potential and career-related interest were gathered using standardised measures supplemented with open-ended responses. The data were analysed to compare the profiles of the successful candidates against those not selected. The selected group showed significantly higher mean scores on meaningfulness and learning potential, and lower scores for career-related interest in law and medicine. Findings suggest that psychological coping, learning potential and career-related preference information can be used to refine the selection of operational force military candidates. 相似文献
953.
Social learning is predicted to evolve in socially living animals provided the learning process is not random but biased by certain socio-ecological factors. One bias of particular interest for the emergence of (cumulative) culture is the tendency to forgo personal behaviour in favour of relatively better variants observed in others, also known as the “copy-if-better” strategy. We investigated whether chimpanzees employ copy-if-better in a simple token-exchange paradigm controlling for individual and random social learning. After being trained on one token-type, subjects were confronted with a conspecific demonstrator who either received the same food reward as the subject (control condition) or a higher value food reward than the subject (test condition) for exchanging another token-type. In general, the chimpanzees persisted in exchanging the token-type they were trained on individually, indicating a form of conservatism consistent with previous studies. However, the chimpanzees were more inclined to copy the demonstrator in the test compared to the control condition, indicating a tendency to employ a copy-if-better strategy. We discuss the validity of our results by considering alternative explanations and relate our findings to the emergence of cumulative culture. 相似文献
954.
S. E. van Nieuwamerongen M. Mendl S. Held N. M. Soede J. E. Bolhuis 《Animal cognition》2017,20(5):907-921
We studied the social and cognitive performance of piglets raised pre-weaning either in a conventional system with a sow in a farrowing crate (FC) or in a multi-suckling (MS) system in which 5 sows and their piglets could interact in a more physically enriched and spacious environment. After weaning at 4 weeks of age, 8 groups of 4 litter-mates per pre-weaning housing treatment were studied under equal and enriched post-weaning housing conditions. From each pen, one pair consisting of a dominant and a submissive pig was selected, based on a feed competition test (FCT) 2 weeks post-weaning. This pair was used in an informed forager test (IFT) which measured aspects of spatial learning and foraging strategies in a competitive context. During individual training, submissive (informed) pigs learned to remember a bait location in a testing arena with 8 buckets (the same bucket was baited in a search visit and a subsequent relocation visit), whereas dominant (non-informed) pigs always found the bait in a random bucket (search visits only). After learning their task, the informed pigs’ individual search visit was followed by a pairwise relocation visit in which they were accompanied by the non-informed pig. Effects of pre-weaning housing treatment were not distinctly present regarding the occurrence of aggression in the FCT and the learning performance during individual training in the IFT. During paired visits, informed and non-informed pigs changed their behaviour in response to being tested pairwise instead of individually, but MS and FC pigs showed few distinct behavioural differences. 相似文献
955.
Can Kabadayi Anastasia Krasheninnikova Laurie O’Neill Joost van de Weijer Mathias Osvath Auguste M. P. von Bayern 《Animal cognition》2017,20(6):1137-1146
The ability to inhibit unproductive motor responses triggered by salient stimuli is a fundamental inhibitory skill. Such motor self-regulation is thought to underlie more complex cognitive mechanisms, like self-control. Recently, a large-scale study, comparing 36 species, found that absolute brain size best predicted competence in motor inhibition, with great apes as the best performers. This was challenged when three Corvus species (corvids) were found to parallel great apes despite having much smaller absolute brain sizes. However, new analyses suggest that it is the number of pallial neurons, and not absolute brain size per se, that correlates with levels of motor inhibition. Both studies used the cylinder task, a detour-reaching test where food is presented behind a transparent barrier. We tested four species from the order Psittaciformes (parrots) on this task. Like corvids, many parrots have relatively large brains, high numbers of pallial neurons, and solve challenging cognitive tasks. Nonetheless, parrots performed markedly worse than the Corvus species in the cylinder task and exhibited strong learning effects in performance and response times. Our results suggest either that parrots are poor at controlling their motor impulses, and hence that pallial neuronal numbers do not always correlate with such skills, or that the widely used cylinder task may not be a good measure of motor inhibition. 相似文献
956.
This paper showcases the work of Third Space professionals in a complex higher education (HE) setting, and specifically its impact on the building of trust relationships and innovative approaches. It makes use of a case-study methodological approach, reflecting on the experiences of various stakeholders within pilot phases. The findings reveal challenges related to maintaining trust relationships, which can be threatened by technicist approaches. The reflective case study explores an innovative live-streaming project and the related pedagogical approaches by Instructional Design experts, as Third Space professionals, who have carved out a critical space within a HE setting. This investigation, and its related lessons, highlights that learning-and-teaching aspects, training and support, reconciliation of trust relationships, can be applied to Third Space professionals in other HE institutions. 相似文献
957.
The theory of evolution continues to be a bone of contention among certain groups of theistic believers. This paper aims to bring some light to the debate about it, by introducing a framework for epistemic appraisal which can provide a realistic and sober assessment of the epistemic credentials of the various parts of evolutionary theory. The upshot is a more nuanced epistemic appraisal of the theory of evolution, which shows that there are significant differences in epistemic standing between its various parts. Any serious conversation about the theory of evolution ought to reflect these facts. 相似文献
958.
959.
Mara van der Meulen Jolanda Veldhuis Barbara R. Braams Sabine Peters Elly A. Konijn Eveline A. Crone 《Cognitive, affective & behavioral neuroscience》2017,17(4):712-723
Media’s prevailing thin-body ideal plays a vital role in adolescent girls’ body image development, but the co-occurring impact of peer feedback is understudied. The present study used functional magnetic resonance imaging (fMRI) to test media imagery and peer feedback combinations on neural activity related to thin-body ideals. Twenty-four healthy female late adolescents rated precategorized body sizes of bikini models (too thin or normal), directly followed by ostensible peer feedback (too thin or normal). Consistent with prior studies on social feedback processing, results showed increased brain activity in the dorsal medial prefrontal cortex (dmPFC)/anterior cingulate cortex (ACC) and bilateral insula in incongruent situations: when participants rated media models’ body size as normal while peer feedback indicated the models as too thin (or vice versa). This effect was stronger for girls with lower self-esteem. A subsequent behavioral study (N = 34 female late adolescents, separate sample) demonstrated that participants changed behavior in the direction of the peer feedback: precategorized normal sized models were rated as too thin more often after receiving too thin peer feedback. This suggests that the neural responses upon peer feedback may influence subsequent choice. Our results show that media-by-peer interactions have pronounced effects on girls’ body ideals. 相似文献
960.
Andrea Schiavio Dylan van der Schyff Julian Cespedes-Guevara Mark Reybrouck 《Phenomenology and the Cognitive Sciences》2017,16(5):785-809
The subject of musical emotions has emerged only recently as a major area of research. While much work in this area offers fascinating insights to musicological research, assumptions about the nature of emotional experience seem to remain committed to appraisal, representations, and a rule-based or information-processing model of cognition. Over the past three decades alternative ‘embodied’ and ‘enactive’ models of mind have challenged this approach by emphasising the self-organising aspects of cognition, often describing it as an ongoing process of dynamic interactivity between an organism and its environment. More recently, this perspective has been applied to the study of emotion in general, opening up interesting new possibilities for theory and research. This new approach, however, has received rather limited attention in musical contexts. With this in mind, we critically review the history of music and emotion studies, arguing that many existing theories offer only limited views of what musical-emotional experience entails. We then attempt to provide preliminary grounding for an alternative perspective on music and emotion based on the enactive/dynamic systems approach to the study of mind. 相似文献