全文获取类型
| 收费全文 | 642篇 |
| 免费 | 81篇 |
| 国内免费 | 30篇 |
专业分类
| 753篇 |
出版年
| 2025年 | 9篇 |
| 2024年 | 13篇 |
| 2023年 | 18篇 |
| 2022年 | 20篇 |
| 2021年 | 43篇 |
| 2020年 | 46篇 |
| 2019年 | 59篇 |
| 2018年 | 46篇 |
| 2017年 | 38篇 |
| 2016年 | 46篇 |
| 2015年 | 27篇 |
| 2014年 | 35篇 |
| 2013年 | 77篇 |
| 2012年 | 22篇 |
| 2011年 | 30篇 |
| 2010年 | 14篇 |
| 2009年 | 36篇 |
| 2008年 | 36篇 |
| 2007年 | 17篇 |
| 2006年 | 28篇 |
| 2005年 | 20篇 |
| 2004年 | 10篇 |
| 2003年 | 11篇 |
| 2002年 | 5篇 |
| 2001年 | 8篇 |
| 2000年 | 4篇 |
| 1999年 | 3篇 |
| 1998年 | 5篇 |
| 1997年 | 4篇 |
| 1996年 | 4篇 |
| 1995年 | 4篇 |
| 1994年 | 5篇 |
| 1993年 | 2篇 |
| 1992年 | 4篇 |
| 1991年 | 1篇 |
| 1990年 | 1篇 |
| 1987年 | 1篇 |
| 1985年 | 1篇 |
排序方式： 共有753条查询结果，搜索用时 15 毫秒
701.
This study investigated the age effects on the control of dynamic balance during step adjustments under temporal constraints. Fifteen young adults and 14 older adults avoided a virtual white planar obstacle by lengthening or shortening their steps under free or constrained conditions. In the anterior–posterior direction, older adults demonstrated significantly decreased center of mass velocity at the swing foot contact under temporal constraints. Additionally, the distances between the ‘extrapolated center of mass’ position and base of support at the swing foot contact were greater in older adults than young adults. In the mediolateral direction, center of mass displacement was significantly increased in older adults compared with young adults. Consequently, older adults showed a significantly increased step width at the swing foot contact in the constraint condition. Overall, these data suggest that older adults demonstrate a conservative strategy to maintain anterior–posterior stability. By contrast, although older adults are able to modulate their step width to maintain mediolateral dynamic balance, age-related changes in mediolateral balance control under temporal constraints may increase the risk of falls in the lateral direction during obstacle negotiation. 相似文献
702.
Previous research has indicated that muscle fatigue due to repeated bouts of physical activity can have negative residual effects on balance; however investigations using multi-joint forms of exercise involved in everyday settings and determination of how control of posture is altered during the physical activity itself are limited. The purpose of this investigation was to evaluate alterations in postural stability before, during, and after prolonged multi-joint STS exercise in healthy young adults. Center of pressure (COP) acquisitions were collected during repetitive STS exercise, while voluntary limits of stability (LOS) testing was performed before, immediately after, and 10 min after STS exercise. By 50% total STS exercise time, fatigue resulted in increased anterio-posterior (y) and medio-lateral (x) COP path lengths (p = 0.003 and p = 0.018 respectively) and an anterior shift of COP at seat-off towards the mid-foot (p = 0.010). No significant change in LOS mean amplitude was found after STS exercise; however a significant fatigue effect resulted in increased COPy sway velocity at maximal lean positions (p = 0.006), but returned to PRE values after 10 min of rest. Declines in postural stability during repetitive STS exercise was associated with reduced control of COP, as well as a reduced ability to stably control COP at extreme postural limits; however, 10 min was adequate in young adults for recovery. These results may have important implications for monitoring fall risk due to acute bouts of exercise induced muscle fatigue from repetitive multi-joint activities such as the STS. 相似文献
703.
Shiri Lev‐Ari 《Cognitive Science》2016,40(8):2050-2064
People differ in the size of their social network, and thus in the properties of the linguistic input they receive. This article examines whether differences in social network size influence individuals’ linguistic skills in their native language, focusing on global comprehension of evaluative language. Study 1 exploits the natural variation in social network size and shows that individuals with larger social networks are better at understanding the valence of restaurant reviews. Study 2 manipulated social network size by randomly assigning participants to learn novel evaluative words as used by two (small network) versus eight (large network) speakers. It replicated the finding from Study 1, showing that those exposed to a larger social network were better at comprehending the valence of product reviews containing the novel words that were written by novel speakers. Together, these studies show that the size of one's social network can influence success at language comprehension. They thus open the door to research on how individuals’ lifestyle and the nature of their social interactions can influence linguistic skills. 相似文献
704.
Temporal discounting (TD), the preference for earlier, smaller rewards over delayed, larger rewards, is a pervasive phenomenon that covaries with Big Five personality traits and Intelligence (IQ). This study provides novel insight by identifying correlates for IQ and Extraversion in the neural representation of TD preferences. An intertemporal choice task was employed, where offers were sequentially presented, distinguishing between one evaluation phase (first offer is presented) and one comparison phase (second offer is presented and values are compared). IQ correlated with responses of caudate nucleus to the subjective values of the offers, suggesting a role of cognitive abilities in modulating reward responses. Extraversion correlated with the strength of functional connectivity of a reward evaluation network centered on ventromedial prefrontal cortex. 相似文献
705.
706.
707.
在神经网络的最新取向下, 探讨阅读脑机制中背侧和腹侧通路的协作机制, 是解决语言认知神经科学多个理论问题共同面临的焦点。本项目拟通过两个脑功能成像实验, 建构汉字阅读的动态因果模型, 系统地考察汉字阅读的神经网络, 以及阅读网络中背、腹侧通路的协作机制。实验一利用快速适应实验范式的优点, 识别和考察汉字阅读涉及的认知成分所对应的功能脑区, 以及脑区联结形成的神经回路, 并建构汉字阅读的动态因果模型; 实验二进一步考察在刺激属性(语音和语义信息)和任务要求下阅读脑区的动态激活及相互作用。通过不同任务下的模型对比, 重点探讨阅读网络的脑区联结模式变化, 尤其是背、腹侧通路受刺激和任务影响时的协作机制。研究结果将为揭示阅读的神经生理模型、解决语言特异性脑区激活的争论等理论问题提供直接的证据, 还能为语言教学、阅读障碍矫治、以及临床应用提供理论基础与指导。 相似文献
708.
采用自编的大学生网络幸福感问卷、网络使用偏好问卷,对400名大学生进行测试,以探索大学生网络幸福感的特点及其与网络使用偏好的关系。结果表明：（1）大学生的网络幸福感总体处于中等偏上水平,网络使用偏好中休闲娱乐维度的得分最高,网络使用偏好类型中普通型居主导地位;（2）网络幸福感和网络使用偏好类型存在显著正相关,其中与休闲娱乐偏好的相关最高;（3）回归分析结果表明,休闲娱乐偏好对网络幸福感有正向预测作用,游戏偏好对网络幸福感中的便利感、活力感、自由感因子有预测作用。 相似文献
709.
710.
Peters JA Hoskins L Prindiville S Kenen R Greene MH 《Journal of genetic counseling》2006,15(6):477-489
The CEGRM was initially conceived as a simple, concise, visual representation of the social interaction domains of information, tangible services and emotional exchanges (Kenen, R., & Peters, J. (2001). J Genet Counsel, 10, 289–309). A blend of the genetic pedigree, genogram, and ecomap, the CEGRM was developed to facilitate contemporary genetic counseling goals. An exploratory pilot study of 20 subjects showed that it was feasible, comfortable and efficiently accomplished, and that the process was useful both for assessment and as an intervention with study participants (Peters, J. A., Kenen, R., Giusti, R., Loud, J., Weissman, N., & Greene, M. H. (2004). Am J Med Genet Part A, 130A, 258–264). Subsequently, we have extended the CEGRM to 150 women from hereditary breast/ovarian cancer (HBOC) families; three different investigators have successfully administered this tool. The preliminary findings from the exploratory study were confirmed in the larger sample. Engaging in the interactive, insight-promoting CEGRM process provides a novel tool for assessing the social context of genetic testing, and helping high-risk women better understand and integrate genetic information into their personal and family identities, health beliefs, and decisions. 相似文献