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   38562篇
  免费   1512篇
  国内免费   15篇
  2019年   384篇
  2018年   573篇
  2017年   571篇
  2016年   619篇
  2015年   457篇
  2014年   578篇
  2013年   2757篇
  2012年   1031篇
  2011年   1021篇
  2010年   708篇
  2009年   657篇
  2008年   972篇
  2007年   942篇
  2006年   867篇
  2005年   786篇
  2004年   746篇
  2003年   708篇
  2002年   753篇
  2001年   1232篇
  2000年   1223篇
  1999年   915篇
  1998年   417篇
  1997年   421篇
  1996年   415篇
  1992年   801篇
  1991年   751篇
  1990年   748篇
  1989年   677篇
  1988年   682篇
  1987年   650篇
  1986年   674篇
  1985年   658篇
  1984年   591篇
  1983年   517篇
  1982年   388篇
  1981年   386篇
  1979年   594篇
  1978年   480篇
  1977年   411篇
  1976年   409篇
  1975年   514篇
  1974年   631篇
  1973年   663篇
  1972年   498篇
  1971年   515篇
  1970年   462篇
  1969年   521篇
  1968年   622篇
  1967年   570篇
  1966年   554篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
201.
Age differences in short-term retroactive interference, unconfounded with age differences in rehearsal in the retention interval of the Brown-Peterson Task, were not found in a cross-sectional study of adults 18-32 and 64-78 years of age. Degree of retroactive interference was manipulated conjointly with distractor interval length (0-15 s). Individual memory span was assessed and used as the list length in order to achieve stimulus equivalence of memory loads across individuals and age groups. An attention-demanding matching task that adjusted itself in difficulty to the individual's attentional capacity was used as the distractor activity. Covert rehearsal during the retention interval was inferred using several measures, including a comparison of distractor task performance in the presence and in the absence of a memory load, and rehearsers were excluded from the primary analyses. We conclude that there is no interference proneness with increasing age in the present study.  相似文献   
202.
Surviving members of the Berkeley Older Generation Study were interviewed and tested with the Wechsler Adult Intelligence Scale in 1969-1970 and again in 1983-1984, when subjects' ages ranged from 73 to 93. Health was assessed by self-reports at both measurement periods. Although many individuals showed some decline in intellectual functioning, substantial individual differences were apparent at all age levels. More than one half of the subjects showed no reliable change, and a minority showed a reliable increase in verbal scores. The role of self-reported health has increasing importance in the maintenance of intellectual functioning in advanced old age.  相似文献   
203.
We investigated longitudinally the effects of a stroke on the social support systems and well-being of the patient's primary support person, both acutely and as the condition stabilized. Individuals who had suffered a first stroke and a primary support person participated in two waves of data collection, carried out in 6-month intervals beginning 7 weeks after the stroke. Our data show that the prevalence of depressive symptoms is from 2 1/2 to 3 1/2 times higher than rates found among representative samples of middle-aged and elderly populations. Mean level of depression did not change over time, although level of optimism declined significantly. Multiple regression analyses showed that levels of depression and perceived burden in support persons are highly related to aspects of the stroke such as its severity, and that demographic variables such as age and income play a relatively minor role in attenuating these relations in the acute adjustment phase. However, from 7 to 9 months after the stroke, well-established demographic variables such as health, income, and age were significant predictors of depression. Individuals who were older and who had good health and higher incomes were least depressed.  相似文献   
204.
Young and older adults were presented with pictures for study. Their recognition of the information was tested at five retention intervals: immediately, and 48 hr, 1 week, 2 weeks, and 4 weeks later. The main finding of interest was that picture recognition did not show an age-related decline until the 1-week retention interval.  相似文献   
205.
206.
The goal of the authors is to (a) create an awareness among counselors about the nature and prevalence of child sexual abuse, (b) examine myths and realities about the topic, and (c) present recommendations for interviewing suspected victims of child sexual abuse.  相似文献   
207.
208.
Legal and nonlegal factors influencing the civil commitment recommendations of psychologists and psychiatrists separately and as a whole were investigated using an experimental design. One hundred and seventy-six psychologists and psychiatrists made recommendations for or against commitment for a series of clinical vignettes wherein the five facets of commitment criterion, legal committability, clinical treatability, alternative resources and presence of psychosis were systematically varied. Results revealed that all facets contributed independently and in combination to the commitment decisions of participants as a whole. It was concluded that mental health professionals may utilize a variety of types of information, beyond the relevant legal criteria, in making actual decisions to initiate civil commitments.  相似文献   
209.
A software package called PAST (Programmer Assessment Software Tools) is described. PAST was designed as a research and diagnostic tool to analyze how programmers develop and test program code. PAST uses line changes between successive compiles to estimate a programmer’s cognitive processing. Line changes are highlighted and graphically presented between any two versions or compiles. Summary graphs and statistics across all versions also are provided. Applications of PAST for expanding our understanding of programming and applying it to research, teaching, and learning are discussed.  相似文献   
210.
High-resolution CRT displays are subject togeometric distortion: lines that are straight in the internal coordinates of the graphics software and hardware are curved when projected onto a plane in the observer’s line of sight. As the available resolution of CRT screens increases, it becomes more difficult to measure and correct for this distortion. We present a simple, highly accurate method for determining the mapping between internal coordinates and the viewing plane. It requires that an observer, using a calibration program, adjust triples of displayed points until they are collinear. A metal straightedge placed between the observer and the screen aids in this judgment. We describe the calibration of an IBM Enhanced Graphics Display in high-resolution mode (350 × 640 pixels), and illustrate how to use the estimated mapping to choose internal coordinates to draw undistorted figures that are accurate to within 0.5 pixel. The method can be used to assess or to correct the accuracy of visual displays. The method is relevant to experiments in spatial vision, spatial perception, perception of dot patterns, and any application in which geometrically accurate stimuli are required.  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