首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3789篇
  免费   235篇
  国内免费   295篇
  4319篇
  2024年   10篇
  2023年   64篇
  2022年   59篇
  2021年   107篇
  2020年   179篇
  2019年   170篇
  2018年   188篇
  2017年   194篇
  2016年   203篇
  2015年   140篇
  2014年   172篇
  2013年   745篇
  2012年   98篇
  2011年   190篇
  2010年   111篇
  2009年   185篇
  2008年   177篇
  2007年   174篇
  2006年   135篇
  2005年   131篇
  2004年   128篇
  2003年   115篇
  2002年   91篇
  2001年   76篇
  2000年   74篇
  1999年   46篇
  1998年   54篇
  1997年   42篇
  1996年   24篇
  1995年   39篇
  1994年   26篇
  1993年   7篇
  1992年   11篇
  1991年   12篇
  1990年   9篇
  1989年   12篇
  1988年   9篇
  1987年   11篇
  1986年   6篇
  1985年   9篇
  1984年   15篇
  1983年   8篇
  1982年   13篇
  1981年   9篇
  1980年   7篇
  1979年   12篇
  1977年   4篇
  1976年   3篇
  1975年   7篇
  1974年   4篇
排序方式: 共有4319条查询结果,搜索用时 15 毫秒
911.
Video summarization is one of the key techniques to access and manage a huge chunk of videos. Video summarization is used to extract the effective contents of a video sequence to generate a concise representation of its content. The involvement of crowdsourcing models in recent years is effectively used by researchers in E-commerce domain to increase the quality of the data contents. In this paper, we present a video summarization framework based on users emotion while they watch videos by analyzing cerebral activities through Electroencephalogram (EEG) signals. Three emotions, namely happy, sad and neutral have been extracted from the EEG signals. Video frames have been synchronized with EEG signals and tagged with various emotions. Finally, a crowdsourcing model has been used for effective summarization of the videos. The qualitative assessment of video summarization has been conducted with the help of user ratings using online Google Forms application. EEG signals of 28 users have been recorded while video streams of different emotions. An average accuracy of 83.93% has been recorded in emotion classification using crowdsourcing. Output summarized videos include dynamic video skims and the corresponding audio stream for better understanding.  相似文献   
912.
在当前的互联网时代下,个体“在非工作时间使用通信技术处理工作”的现象已经非常普遍,并因其对个体日常工作生活适应可能产生的深远影响而受到研究者的广泛关注。基于对该领域已有研究文献的全面回顾,本文着重探讨了非工作时间使用通信工具处理对个体工作生活适应的“双刃剑”效应及效应发生的心理机制,并对该领域未来的研究方向进行了针对性的展望。  相似文献   
913.
Background/Objective: Lower levels in well-being have been observed in individuals with Major Depression (MDD) and Social Phobia (SP), but well-planned direct comparisons with control individuals, not suffering from a mental disorder, are lacking. Furthermore, MDD is highly comorbid with anxiety disorders, and SP with depressive disorders. This study is among the first to examine differences in well-being in individuals with a clinical diagnosis of MDD or SP compared to individuals with no such diagnosis and to test differences in well-being within the combined diagnostic categories respective with and without anxiety-depressive comorbidity. Method: Participants were 119 individuals with a diagnosis of MDD, 47 SP and 118 controls. Results: Results revealed that overall well-being as well as emotional, psychological, and social well-being were lower in the MDD and SP group compared to the control group. Individuals with comorbidity reported lower well-being than individuals without comorbidity. Conclusions: These findings have clinical implications as presence of comorbidity may require a different therapeutic approach than with no comorbidity.  相似文献   
914.
The State-Trait Anxiety Inventory for Children is a self-report instrument inspired on the State-Trait theory extended by Spielberger that measures a momentary state of anxiety (state) and a stable tendency to experience anxiety (trait). This study presents an exploratory adaptation of the Trait Scale and provides its psychometric properties for European Portuguese children and adolescents. The influence of sex and age were also explored. Our sample, composed of 402 participants aged 8–14 years, revealed a mean anxiety value of 28.37 (SD = 5.99). As expected, females revealed higher levels of anxiety than boys. Higher anxiety was obtained in our youngest group as compared to the oldest group. The exploratory factor analysis led to retaining only 16-items that presented acceptable adjustment to a one-factorial solution. Good indexes were obtained in the confirmatory analysis. The results also revealed good internal consistency and good test-retest reliability. Our results provide initial evidence that this scale is adequate to measure trait-anxiety in European Portuguese young people.  相似文献   
915.
Event-related potential (ERP) studies have attempted to discover the processes that underlie conscious visual perception by contrasting ERPs produced by stimuli that are consciously perceived with those that are not. Variability of the proposed ERP correlates of consciousness is considerable: the earliest proposed ERP correlate of consciousness (P1) coincides with sensory processes and the last one (P3) marks postperceptual processes. A negative difference wave called visual awareness negativity (VAN), typically observed around 200 ms after stimulus onset in occipitotemporal sites, gains strong support for reflecting the processes that correlate with, and possibly enable, aware visual perception. Research suggests that the early parts of conscious processing can proceed independently of top-down attention, although top-down attention may modulate visual processing even before consciousness. Evidence implies that the contents of consciousness are provided by interactions in the ventral stream, but indispensable contributions from dorsal regions influence already low-level visual responses.  相似文献   
916.
To examine whether anticipatory attention or expectancy is a cognitive process that is automatic or requires conscious control, we employed a paired-stimulus event-related potential (ERP) paradigm during the transition to sleep. The slow negative ERP wave observed between two successive stimuli, the Contingent Negative Variation (CNV), reflects attention and expectancy to the second stimulus. Thirteen good sleepers were instructed to respond to the second stimulus in a pair during waking sessions. In a non-response paradigm modified for sleep, participants then fell asleep while tones played. As expected, N1 decreased and P2 increased in amplitude systematically with the loss of consciousness at sleep onset; the CNV was increasingly more positive. Sleep onset latency was correlated with the amplitude of the CNV. The systematic attenuation of the CNV waveform at sleep onset and its absence in sleep indicates that anticipatory attention requires endogenous conscious control.  相似文献   
917.
Previous research has indicated an increase in stress levels and cognitive intrusions after natural disasters. These previous studies have not, however, assessed the impact disaster induced cognitive disruption has on human performance. In the present report, we investigated the impact of the 7.1 magnitude 2010 Christchurch, New Zealand earthquake on self-reported earthquake-induced cognitive disruption and its relationship to performance on the Sustained Attention to Response Task (SART). Participants who self-reported greater cognitive disruption induced by the earthquake also had higher levels of errors of commission during SART (r = .80, p < .001). This was even the case when controlling for earthquake-induced anxiety, depression, participant sex, and self-reported sleep amount. Post-disaster assessments need to include the impact of the events directly on cognitive self-regulation and conscious thoughts, in addition to more clinical constructs, such as anxiety and depression.  相似文献   
918.
919.
This review of 20 years of developmental research on Executive Functions (EF) offers a broad‐brushstroke picture that touches on multiple issues including: (i) findings from typical and atypical groups, from infancy to adolescence; (ii) advances in assessment tools and in statistical analysis; (iii) the interplay between EF and other cognitive systems (e.g. those involved in children's developing understanding of mind, and in their processing of reward signals); (iv) integration of cognitive and neuroscience perspectives on EF; and (v) environmental factors that have either a positive influence (e.g. training/intervention programmes; parental scaffolding) or a negative influence (e.g. maltreatment, neglect, traumatic brain injury) on EF. Of the several themes to emerge from this review, two are particularly important; these concern the need to adopt developmental perspectives and the potential importance for intervention work of research on social influences on EF. Specifically, the review highlights both developmental continuities (e.g. in the correlates of EF) and contrasts (e.g. in the nature of EF and its neural substrates) and calls for research that compares developmental trajectories for EF in different groups (e.g. children with autism versus ADHD). In addition, findings from both family‐based research and randomized controlled trials of school‐based interventions highlight the importance of environmental influences on EF and so support the development of interventions to promote EF and hence improve children's academic and social outcomes. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
920.
Background: Increasing numbers of HIV‐infected gay men acquire hepatitis C virus (HCV) co‐infection, which causes serious medical consequences. Treatment for HCV is associated with many severe side effects, in some cases psychological, and many patients subsequently fail to adhere, even when psychological services are utilised, to improve treatment adherence. Objective: This qualitative study aimed to explore the experiences of HIV‐infected gay men undergoing treatment for HCV in order to inform psychological services to better meet specific treatment needs of this population. Methods: Thirteen HIV‐infected gay men who had undergone HCV treatment were interviewed and a qualitative analysis was conducted. Participants described HCV and its treatments in the context of their relationships and lifestyles. Findings: Four domains emerged: HCV diagnosis and treatment; HCV treatment education; change in sense of self; and sexual risk‐taking. Adhering to treatment was a significant challenge for all participants and emerged across all domains. Discussion: Psychological services for this population of co‐infected gay men should assist this clinical population not only with adherence to hepatitis C treatment but should also be available at an earlier stage in the process to help patients make informed choices about whether or not to begin a course of treatment. Assessing factors such as coping strategies, treatment readiness and knowledge, self‐awareness, and level of risk‐taking, can guide clinicians in tailoring treatment and adherence planning for HIV/HCV‐co‐infected gay men.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号