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   3919篇
  免费   188篇
  国内免费   3篇
  2020年   56篇
  2019年   67篇
  2018年   104篇
  2017年   122篇
  2016年   112篇
  2015年   68篇
  2014年   98篇
  2013年   489篇
  2012年   133篇
  2011年   133篇
  2010年   94篇
  2009年   90篇
  2008年   160篇
  2007年   141篇
  2006年   106篇
  2005年   123篇
  2004年   96篇
  2003年   98篇
  2002年   90篇
  2001年   42篇
  2000年   53篇
  1999年   49篇
  1998年   63篇
  1997年   42篇
  1996年   44篇
  1995年   41篇
  1994年   47篇
  1992年   54篇
  1990年   38篇
  1989年   42篇
  1988年   42篇
  1987年   36篇
  1986年   49篇
  1985年   38篇
  1984年   57篇
  1983年   41篇
  1982年   41篇
  1981年   46篇
  1980年   51篇
  1979年   40篇
  1978年   50篇
  1977年   56篇
  1976年   52篇
  1975年   57篇
  1974年   50篇
  1973年   56篇
  1972年   37篇
  1971年   35篇
  1970年   40篇
  1968年   42篇
排序方式: 共有4110条查询结果,搜索用时 31 毫秒
991.
The effects of perceptual motor training in children with learning disabilities have been hotly debated for many years. Proponents have included many of the pioneers in the fields of learning disabilities and motor development. Among the challenges perhaps the most sophisticated one has been the meta-analysis by Kavale and Mattson. Their conclusion was that perceptual motor training was not an effective intervention for children with disabilities. The purpose of this project was to analyze critically the Kavale and Mattson meta-analysis from the perspective of an adapted physical educator and to consider the validity of this meta-analysis when examining multiple interventions dealing with a multitude of disabilities. A critical analysis of all 180 studies question their conclusions.  相似文献   
992.
Describing memory for a nonverbal perceptual stimulus can impair recognition. This verbal overshadowing effect may occur when perceptual expertise exceeds verbal expertise, but previous evidence for this hypothesis has been strictly correlational. We conducted two experiments, exploring the relation between expertise and verbal overshadowing by manipulating perceptual and conceptual knowledge. Participants received perceptual training (categorizing mushrooms), conceptual training (lecture), or no training, then viewed a mushroom and described it or not. A recognition test followed. In Experiment 1, perceptual training increased susceptibility to verbalization relative to the no training condition. However, conceptual training did not insulate individuals from the verbal overshadowing effect. Experiment 2 was modified to enhance both forms of training. It replicated the finding that perceptual training increases vulnerability to verbal overshadowing, and indicated that, when sufficiently emphasized, verbalization may be useful following conceptual training. The results demonstrate the role that different forms of learning and expertise may play in mediating language influences on recognition memory.  相似文献   
993.
This article reports on a study of autobiographical memory in two older adults, wife and husband, over a retention interval of 20 years. The female participant kept a 20-year log of daily events. A sampling of events that varied in distinctiveness, from unique, one-of-a-kind events to routine, almost daily events, was used to examine cued recall using an incremental scoring system. Each event recalled was also rated on phenomenological scales of remembering versus knowing, rehearsal, and importance. The strongest effect on recall was the order of the cues, with an initial what cue, containing the content of the event, proving superior to cues containing who or where elements. When was the most effective second cue. The results demonstrate regularity in retention over time and highlighted the utility of this approach for understanding the factors that influence autobiographical memory performance.  相似文献   
994.
In gait research it has often been assumed that variability and stability are negatively correlated, where increases in variability are assumed to equate with increases in instability. The purpose of this paper is to illustrate that variability does not always equate with stability. To proof this point, a method was developed to directly assess stability and variability during the application of a visual perturbation at different walking speeds. Walking variability was measured by using the average standard deviation of the knee joint angle across the gait cycle. Walking stability was measured by the recovery time of the knee joint angle trajectory from the distortion induced by a visual perturbation that was delivered at the beginning of the stance phase. Five participants were required to walk at six different velocities on a treadmill (0.67, 0.80, 0.94, 1.07, 1.21, and 1.34 m/s). The coefficients of intraclass correlations for the experiment were 83% and 80% for the calculated stability and variability, respectively. The calculated stabilities were not sensitive to changes in walking speed (p>0.98). The calculated variability however decreased with increases in walking speed (p=0.004). No significant correlation between variability and stability was observed (r=-0.002). We suggest that gait stability is independent of variability during locomotion and should thus be measured independently.  相似文献   
995.
996.
We describe an ecological momentary assessment (EMA) protocol designed to measure daily life experiences along several psychosocial dimensions (Social Conflict, Task Demand, Decisional Control, Negative Affect, and Arousal) hypothesized to be relevant for cardiovascular disease risk. In a large community sample, these assessments have been administered in conjunction with ambulatory blood pressure (ABP) monitoring and measures of subclinical cardiovascular disease. Several results have emerged that support the promise of this approach. First of all, each of these dimensions of experience appears to be a trigger for cardiovascular activation, with movement on each scale being associated with significant within-person changes in heart rate and blood pressure in the natural environment. Second, there appear to be individual differences in physiological responsiveness to these dimensions of daily experience, with such differences being associated in some cases with laboratory-based assessments of cardiovascular reactivity, as might be expected. Third, EMA ratings are associated in several instances with (between-person) stable individual differences in ABP readings. And finally, we have found that some of the characteristics defined by our EMA ratings are related to measures of subclinical atherosclerosis. Such effects appear to be mediated, in part, by ABP. The advantages of using EMA measures for capturing the effects of psychosocial stressors are highlighted by comparing the predictive validity of these daily life assessments to traditional global self-reports. We conclude by describing future plans for use of this type of assessment protocol for helping us to characterize psychosocial characteristics relevant to cardiovascular disease risk. Personality and social processes during daily living may have an important impact not only on psychological functioning but also on physical health and disease. In this article we review our recent work involving the assessment of daily experience as a means of better understanding the role of psychosocial stress in cardiovascular disease risk. First, we outline the rationale for our interest in daily experience sampling for examining these processes, and we describe the methods we have adopted for this purpose. Next, we review findings from a recent study in which we have used these approaches to examine the role of psychosocial stress on ABP and atherosclerosis in a community-dwelling sample. We compare our approach to more traditional (global self-report and laboratory-observation) methods for examining these relationships in humans, and we discuss potential future directions for use of daily experience sampling in studies of health and behavior.  相似文献   
997.
Crewmember performance before, during, and after spaceflight   总被引:1,自引:0,他引:1  
The development of technologies for monitoring the welfare of crewmembers is a critical requirement for extended spaceflight. Behavior analytic methodologies provide a framework for studying the performance of individuals and groups, and brief computerized tests have been used successfully to examine the impairing effects of sleep, drug, and nutrition manipulations on human behavior. The purpose of the present study was to evaluate the feasibility and sensitivity of repeated performance testing during spaceflight. Four National Aeronautics and Space Administration crewmembers were trained to complete computerized questionnaires and performance tasks at repeated regular intervals before and after a 10-day shuttle mission and at times that interfered minimally with other mission activities during spaceflight. Two types of performance, Digit-Symbol Substitution trial completion rates and response times during the most complex Number Recognition trials, were altered slightly during spaceflight. All other dimensions of the performance tasks remained essentially unchanged over the course of the study. Verbal ratings of Fatigue increased slightly during spaceflight and decreased during the postflight test sessions. Arousal ratings increased during spaceflight and decreased postflight. No other consistent changes in rating-scale measures were observed over the course of the study. Crewmembers completed all mission requirements in an efficient manner with no indication of clinically significant behavioral impairment during the 10-day spaceflight. These results support the feasibility and utility of computerized task performances and questionnaire rating scales for repeated measurement of behavior during spaceflight.  相似文献   
998.
This study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).  相似文献   
999.
The authors highlight the utility of distribution-analytical techniques in the study of individual differences and clinical disorders. Cognitive deficits associated with attention-deficit/hyperactivity disorder (AD/HD) were examined by using delta-plot analyses of performance data (reaction time and accuracy) obtained through the use of a prototypical conflict task, the Eriksen flanker task. In 20 children with AD/HD (compared with matched control participants), overall performance measures indicated a marginal performance deficit. Delta-plot analyses indicated that performance deficits associated with AD/HD involve response inhibition but not automatic response activation. In a within-subjects titration study, the response inhibition deficit was eliminated by methylphenidate treatment, but these effects were highly dose specific. The beneficial effect of methylphenidate was clarified further after correcting for inter-individual variation in sensitivity to medicine dosage.  相似文献   
1000.
This paper describes a hypothesis of Tronick's (2002) that positive and negative affect activation waves with changing amplitudes based on positive and negative lived experiences are the sources of persistent or regularly recurrent moods of feeling upbeat or downbeat. The characteristics of discrete affects, moods, and affect states are discussed in the light of a previous study based on clinical observation (Lichtenberg, Lachmann, and Fosshage 1996). The clinical experience theory underpinning that study is then compared with Tronick's Sanderian activation wave theory. A case example is presented, and the overall relevance of Tronick's theory to clinical work 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