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   4734篇
  免费   9篇
  国内免费   1篇
  2018年   117篇
  2017年   104篇
  2016年   180篇
  2015年   98篇
  2014年   31篇
  2013年   79篇
  2012年   267篇
  2011年   257篇
  2010年   29篇
  2009年   27篇
  2008年   38篇
  2007年   37篇
  2006年   52篇
  2005年   1324篇
  2004年   670篇
  2003年   454篇
  2002年   140篇
  2001年   32篇
  2000年   14篇
  1999年   27篇
  1998年   9篇
  1996年   10篇
  1995年   9篇
  1994年   16篇
  1993年   7篇
  1992年   27篇
  1991年   44篇
  1990年   59篇
  1989年   44篇
  1988年   28篇
  1987年   44篇
  1986年   39篇
  1985年   32篇
  1984年   29篇
  1983年   23篇
  1979年   34篇
  1978年   13篇
  1977年   8篇
  1976年   11篇
  1975年   29篇
  1974年   34篇
  1973年   31篇
  1972年   25篇
  1971年   26篇
  1970年   18篇
  1969年   19篇
  1968年   17篇
  1967年   17篇
  1966年   17篇
  1965年   7篇
排序方式: 共有4744条查询结果,搜索用时 15 毫秒
901.
Genetic studies of stuttering in a founder population   总被引:2,自引:0,他引:2  
Genome-wide linkage and association analyses were conducted to identify genetic determinants of stuttering in a founder population in which 48 individuals affected with stuttering are connected in a single 232-person genealogy. A novel approach was devised to account for all necessary relationships to enable multipoint linkage analysis. Regions with nominal evidence for linkage were found on chromosomes 3 (P=0.013, 208.8 centiMorgans (cM)), 13 (P=0.012, 52.6 cM), and 15 (P=0.02, 100 cM). Regions with nominal evidence for association with stuttering that overlapped with a linkage signal are located on chromosomes 3 (P=0.0047, 195 cM), 9 (P=0.0067, 46.5 cM), and 13 (P=0.0055, 52.6 cM). We also conducted the first meta-analysis for stuttering using results from linkage studies in the Hutterites and The Illinois International Genetics of Stuttering Project and identified regions with nominal evidence for linkage on chromosomes 2 (P=0.013, 180-195 cM) and 5 (P=0.0051, 105-120 cM; P=0.015, 120-135 cM). None of the linkage signals detected in the Hutterite sample alone, or in the meta-analysis, meet genome-wide criteria for significance, although some of the stronger signals overlap linkage mapping signals previously reported for other speech and language disorders. EDUCATIONAL OBJECTIVES: After reading this article, the reader will be able to: (1) summarize information about the background of common disorders and methodology of genetic studies; (2) evaluate the role of genetics in stuttering; (3) discuss the value of using founder populations in genetic studies; (4) articulate the importance of combining several studies in a meta-analysis; (5) discuss the overlap of genetic signals identified in stuttering with other speech and language disorders.  相似文献   
902.
Children (2–13 years at time of injury) were interviewed four times about an injury that required hospital Emergency Room treatment, namely at 1 week, 6 months, 1 year, and 2 years. The consistency of children's reports was assessed and all children gave mostly the same information at each interview, although consistency was higher for older children and for injury rather than hospital details. Furthermore, details recalled at every interview were virtually always accurate while details that were sometimes omitted were a little less likely to be accurate. New information that was introduced after 6 months was more likely to be accurate than inaccurate but new information introduced at 1 or 2 years post‐injury was just as likely to be wrong as right (except for 12–13‐year‐olds). Implications for forensic situations are discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
903.
A framework for accounting for emotional phenomena proposed by Sokolov and Boucsein (2000) employs conceptual dimensions that parallel those of hue, brightness, and saturation in color vision. The approach that employs the concepts of emotional quality. intensity, and saturation has been supported by psychophysical emotional scaling data gathered from a few trained observers. We report cortical evoked potential data obtained during the change between different emotions expressed in schematic faces. Twenty-five subjects (13 male, 12 female) were presented with a positive, a negative, and a neutral computer-generated face with random interstimulus intervals in a within-subjects design, together with four meaningful and four meaningless control stimuli made up from the same elements. Frontal, central, parietal, and temporal ERPs were recorded from each hemisphere. Statistically significant outcomes in the P300 and N200 range support the potential fruitfulness of the proposed color-vision-model-based approach to human emotional space.  相似文献   
904.
The mirror effect refers to a rather general empirical finding showing that, for two classes of stimuli, the class with the higher hit rates also has a lower false alarm rate. In this article, a parsimonious theory is proposed to account for the mirror effect regarding, specifically, high- and low-frequency items and the associated receiver-operating curves. The theory is implemented in a recurrent network in which one layer represents items and the other represents contexts. It is shown that the frequency mirror effect is found in this simple network if the decision is based on counting the number of active nodes in such a way that performance is optimal or near optimal. The optimal performance requires that the number of active nodes is low, only nodes active in the encoded representation are counted, the activation threshold is set between the old and the new distributions, and normalization is based on the variance of the input. Owing to the interference caused by encoding the to-be-recognized item in several preexperimental contexts, the variance of the input to the context layer is greater for highthan for low-frequency items, which yields lower hit rates and higher false alarm rates for high- than for low-frequency items. Although initially the theory was proposed to account for the mirror effect with respect to word frequency, subsequent simulations have shown that the theory also accounts for strength-based mirror effects within a list and between lists. In this case, consistent with experimental data, the variance theory suggests that focusing attention to the more difficult class within a list affects the hit rate, but not the false alarm rate and not the standard deviations of the underlying density, leading to no mirror effect.  相似文献   
905.
Orienting attention involuntarily to the location of a sensory event influences responses to subsequent stimuli that appear in different modalities with one possible exception: orienting attention involuntarily to a sudden light sometimes fails to affect responses to subsequent sounds (e.g., Spence & Driver, 1997). Here we investigated the effects of involuntary attention to a brief flash on the processing of subsequent sounds in a design that eliminates stimulus-response compatibility effects and criterion shifts as confounding factors. In addition, the neural processes mediating crossmodal attention were studied by recording event-related brain potentials. Our data show that orienting attention to the location of a spatially nonpredictive visual cue modulates behavioural and neural responses to subsequent auditory targets when the stimulus onset asynchrony is short (between 100 and 300 ms). These findings are consistent with the hypothesis that involuntary shifts of attention are controlled by supramodal brain mechanisms rather than by modality-specific ones.  相似文献   
906.
Much research within decision-making has used the standard gambling paradigm, where decision outcomes depend only on chance. Many real life decisions, however, imply personal control over decision outcomes. This paper addressed the question of how internal controllability influences decision-making. Internal controllability is assumed (i) to enhance unrealistic optimism and (ii) to result in a better cost:benefit ratio. Both tendencies support each other and predict an enhanced attractiveness for internal and controllable choice options. Participants read a scenario and made a decision afterwards. Results supported the prediction: decision-makers take the option they can personally control. This finding widens the narrow perspective inherent in much previous research based on the gambling paradigm.  相似文献   
907.
The authors describe the development of the Religious Occupations and Stress Questionnaire (ROS), which attempts to fill the need for an appropriate measure of the stress experienced by individuals in religious occupations. The ROS has 4 stress‐related subscales (General Stress. Occupational Stress, Identity/Image Stress, and Gender Issues Stress) and a Coping subscale. Results of reliability and validity studies of the ROS with male and female Protestants, Catholics, and Jews who were in religious occupations indicated high internal consistency, test‐retest reliability, and construct validity.  相似文献   
908.
Anxiety, nausea and vomiting before, during and after chemotherapy administration were studied in 50 cancer patients. In addition, patient responses to the Autonomic Perception Questionnaire (APQ) and their relation to the anxiety, nausea and vomiting scores was studied. Anticipatory anxiety occurred in 66% and anticipatory nausea in 40% of the patients; 14% showed anticipatory vomiting. The number of patients reporting anxiety decreased to 38% after chemotherapy, whereas nausea and vomiting increased to 47 and 49%, respectively. APQ scores correlated significantly with anxiety and nausea reports during all time periods, but not with the frequency of vomiting.  相似文献   
909.
Sleep in the dove Zenaida asiatica   总被引:1,自引:0,他引:1  
Electrographic and behavioral observations were made in five adult birds of the genus Zenaida asiatica. Five different vigilance states were quantitated: (1) Active waking (Aw) was characterized by constant behavioral activity; the nuchal electromyogram was tonically active with bursts associated to movements. The electroencephalographic pattern was low voltage and high frequency. (2) Quiet waking (Qw) was characterized by diminished behavioral activity and the EEG pattern was similar to that of Aw. (3) Drowsiness (D) was characterized by behavioral calm. Frequency of cerebral activity diminished progressively, but there were short periods of desynchronization corresponding to brief awakenings. (4) Slow wave sleep (SWS); during this period there was behavioral rest and EEG pattern of continuous slow waves and the nuchal EMG was tonically reduced. Spindles of sleep were not observed. (5) Paradoxical sleep (SP), behaviorally characterized by phasic manifestations consisting of noddings originated by rapid falling down of head and bursts of rapid eye movements. EEG activity was like that of waking state. EMG activity was maintained at the same level as during SWS but sometimes it decreased lightly. Total atonie was not observed. Sleep percentages were higher when recordings were done during the nocturnal period.  相似文献   
910.
The present article interprets mindfulness from the point of view of the effects of language and cognition on human action. Relational Frame Theory is described to show how human suffering is created by entanglement with the cognitive networks made possible by language. Mindfulness can be understood as a collection of related processes that function to undermine the dominance of verbal networks, especially involving temporal and evaluative relations. These processes include acceptance, defusion, contact with the present moment, and the transcendent sense of self. Each of these components of mindfulness are targeted in Acceptance and Commitment Therapy, and there is some evidence that they underlie the therapeutic changes induced by this approach. The relation between the present approach to mindfulness and other approaches is discussed.  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