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   2459篇
  免费   259篇
  国内免费   206篇
  2024年   4篇
  2023年   46篇
  2022年   30篇
  2021年   53篇
  2020年   111篇
  2019年   147篇
  2018年   105篇
  2017年   159篇
  2016年   120篇
  2015年   87篇
  2014年   105篇
  2013年   446篇
  2012年   80篇
  2011年   102篇
  2010年   58篇
  2009年   129篇
  2008年   128篇
  2007年   112篇
  2006年   91篇
  2005年   106篇
  2004年   92篇
  2003年   75篇
  2002年   68篇
  2001年   68篇
  2000年   44篇
  1999年   34篇
  1998年   44篇
  1997年   38篇
  1996年   26篇
  1995年   54篇
  1994年   19篇
  1993年   8篇
  1992年   15篇
  1991年   8篇
  1989年   7篇
  1988年   10篇
  1987年   4篇
  1986年   3篇
  1985年   8篇
  1984年   11篇
  1983年   11篇
  1982年   5篇
  1981年   7篇
  1980年   12篇
  1979年   10篇
  1978年   6篇
  1977年   7篇
  1976年   3篇
  1975年   2篇
  1974年   4篇
排序方式: 共有2924条查询结果,搜索用时 15 毫秒
151.
We assessed the effects of time-on-task on cognitive control expressed by the CRN/Nc and the extent to which motivation modulates this relationship. We utilized two groups of participants, who were told that their performance would (evaluation condition) or would not (control condition) be evaluated online. Both groups performed a version of the Eriksen Flanker Task for 60 min. We observed classical vigilance lowering, manifested by a progressive performance decline with time-on-task, in the control, but not in the evaluation, condition. In the latter, performance remained stable throughout the task. ERP analysis indicated the same interaction in our main component of interest, the CRN/Nc, whose amplitude decreased from the first to the last period in the control condition but remained stable over time in the evaluation condition. To our knowledge, this study is the first to demonstrate the impact of motivation on monitoring processes as indexed by the correct response negativity, in the context of a prolonged task. Vigilance lowering caused by a repetitive and prolonged flanker task, results in compromised response control and compromised control of correct responses. Our results suggest that alterations in ACC functioning may underlie vigilance decline and can be viewed as evidence that the action monitoring functions of the ACC can be positively affected by motivation.  相似文献   
152.
153.
在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平(注意捕获、注意抑制),通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。  相似文献   
154.
155.
In the family‐based prevention science literature, family functioning, defined as positive parenting, parental involvement, family cohesion, family communication, parental monitoring of peers, and parent–adolescent communication, has been shown to ameliorate HIV risk behaviors in Hispanic youth. However, the majority of studies have relied solely on parent or adolescent reports and we know very little about parent–adolescent family functioning discrepancies. Therefore, the purpose of this study was to examine whether and to what extent parent–adolescent discrepancies in family functioning increased the risk of HIV risk behaviors, including substance use and sexual risk behaviors, and whether these associations vary as a function of acculturation and youth gender. A total of 746 Hispanic 8th grade youth and their primary caregivers were included in the study. Structural equation modeling findings indicate that parent–adolescent family functioning discrepancies are associated with an increased risk of Hispanic adolescent HIV risk behaviors, including lifetime and past 90‐day alcohol and illicit drug use, and early sex initiation. In addition, study findings indicate that results vary by acculturation and youth gender. Findings are discussed in the context of existing family‐based research and practice in preventing and reducing HIV risk behaviors among Hispanic youth and their families.  相似文献   
156.
Complex relationships exist between eating behaviour and personal and environmental factors. Rural and urban geographic contexts seem to play a role in eating behaviour, and therefore deserve a deeper study. A healthy eating behaviour and the conditions that promote it are a major issue in the promotion of adolescent health. The study aims to investigate the associations between the area of residence (urban vs. rural), self‐regulation strategies (TESQ‐E) and eating behaviours among children and adolescents. A total of 11,820 adolescents (50.6% girls) participated in the study, with a mean age of 13.30 years (SD= 2.13). Nine countries (The Netherlands, United Kingdom, Poland, Portugal, Denmark, Romania, Germany, Finland and Belgium) completed a questionnaire in the school context, asking about the use of self‐regulation strategies, eating behaviour awareness/care and sociodemographic questions such as age, gender and residential area. Both areas of residence (urban vs. rural) are associated with eating awareness/care in Romania and Portugal, controlling for age, gender and self‐regulation strategies. In some European countries at least, and most probably around the world, health promotion should focus on an ecological approach that includes the understanding of the effect of both environmental factors and personal skills on eating behaviour/awareness.  相似文献   
157.
The present study examined the role of alerting in modulating attentional bias to salient events. In a global/local processing task, participants were presented with a large arrow (global level) comprised of smaller arrows (local level) pointing in the same or opposite directions and had to indicate the direction of the large or small arrows in different blocks. Saliency of the global and local levels was manipulated, creating global-salient and local-salient conditions. Alerting signals were presented in half of the trials prior to the target. Results revealed a double dissociation in the effects of alerting on global/local interference effects. In a global salient condition, alerting increased global interference and decreased local interference. In a local salient condition, alerting reduced global interference and increased local interference. We demonstrate that within a single task, alerting can increase and reduce conflict based on perceptual saliency. These findings help to better understand disorders like hemispatial neglect in which both arousal and attention to salient events are impaired. These results also challenge previous theories suggesting that alerting acts to increase conflict interference. We argue that alerting is an adaptive mechanism that diverts attention to salient events, but comes at a cost when selective attention to less salient details is required.  相似文献   
158.
The survival processing paradigm has recently drawn attention to the functional aspects of memory functioning. The survival effect, characterized by better memory performance when information is processed in a survival context, as compared with a variety of controls, is now well established in healthy populations. The main goal of this study was to test this paradigm in a group of cognitively impaired older adults and elderly; their data were compared to the data obtained in a group of healthy older adults and elderly. Seventeen cognitively impaired and 17 healthy participants performed a typical survival task using a blocked within‐subject design procedure and free recall as the memory test. The healthy older adults and elderly performed better on this memory task as well as on other tests included in a neuropsychological evaluation protocol. Importantly, both groups benefited from survival processing. These results provide further support for the power of survival processing, extending this phenomenon to cognitively impaired aging participants. The data also suggest that the survival effect is not simply a form of deep processing. Potential applied considerations are presented.  相似文献   
159.
The multisensory response enhancement (MRE), occurring when the response to a visual target integrated with a spatially congruent sound is stronger than the response to the visual target alone, is believed to be mediated by the superior colliculus (SC) (Stein & Meredith, 1993). Here, we used a focused attention paradigm to show that the spatial congruency effect occurs with red (SC-effective) but not blue (SC-ineffective) visual stimuli, when presented with spatially congruent sounds. To isolate the chromatic component of SC-ineffective targets and to demonstrate the selectivity of the spatial congruency effect we used the random luminance modulation technique (Experiment 1) and the tritanopic technique (Experiment 2). Our results indicate that the spatial congruency effect does not require the distribution of attention over different sensory modalities and provide correlational evidence that the SC mediates the effect.  相似文献   
160.
The objective of this study was to extend the probability of treatment benefit method by adding treatment condition as a stratifying variable, and illustrate this extension of the methodology using the Child and Adolescent Anxiety Multimodal Study data. The probability of treatment benefit method produces a simple and practical way to predict individualized treatment benefit based on pretreatment patient characteristics. Two pretreatment patient characteristics were selected in the production of the probability of treatment benefit charts: baseline anxiety severity, measured by the Pediatric Anxiety Rating Scale, and treatment condition (cognitive-behavioral therapy, sertraline, their combination, and placebo). We produced two charts as exemplars which provide individualized and probabilistic information for treatment response and outcome to treatments for child anxiety. We discuss the implications of the use of the probability of treatment benefit method, particularly with regard to patient-centered outcomes and individualized decision-making in psychology and psychiatry.  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