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   2340篇
  免费   163篇
  2024年   5篇
  2023年   49篇
  2022年   39篇
  2021年   67篇
  2020年   86篇
  2019年   111篇
  2018年   138篇
  2017年   127篇
  2016年   131篇
  2015年   91篇
  2014年   116篇
  2013年   306篇
  2012年   172篇
  2011年   157篇
  2010年   76篇
  2009年   92篇
  2008年   103篇
  2007年   102篇
  2006年   72篇
  2005年   81篇
  2004年   63篇
  2003年   55篇
  2002年   47篇
  2001年   30篇
  2000年   23篇
  1999年   16篇
  1998年   18篇
  1997年   13篇
  1996年   12篇
  1995年   8篇
  1994年   5篇
  1993年   3篇
  1992年   8篇
  1991年   8篇
  1990年   7篇
  1989年   4篇
  1988年   6篇
  1987年   3篇
  1986年   4篇
  1985年   2篇
  1983年   5篇
  1982年   13篇
  1981年   4篇
  1980年   2篇
  1979年   4篇
  1978年   2篇
  1973年   5篇
  1972年   2篇
  1967年   2篇
  1966年   3篇
排序方式: 共有2503条查询结果,搜索用时 15 毫秒
21.
It has been established through several decades of research that children's home environments significantly influence their development. Many researchers have also been interested in expanding research beyond indirect measures of the home environment, such as socioeconomic status, to help understand the nature of specific environmental mechanisms which influence early behavior and cognitive development. The Home Observation for Measurement of the Environment (HOME) Inventory was developed to meet these needs. Specifically, HOME measures the quality of stimulation in a child's early family environment. Almost all studies of the approach's reliability and validity have been conducted with US samples. HOME is, however, being used in other countries. The authors report their findings from a study of whether the psychometric properties of HOME based upon US samples parallel those found in Costa Rica, and whether HOME discriminates between Costa Rican environments with different associations to child health and development. Focus centers upon the infant/toddler version of the HOME Inventory. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardization sample from Little Rock, Arkansas. The study found the HOME Inventory to be helpful in identifying children at risk for delayed development in this Latin American sample. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anemia in infancy, a condition associated with long-lasting developmental disadvantage.  相似文献   
22.
In this rejoinder to Tidwell and Corona Garrett (1994), the authors discuss three important aspects of the term at risk that help to clarify its meaning.  相似文献   
23.
In this paper, we show that, when lifting an object using a precision grip with the distal pads of the thumb and index finger at its sides, the perceived weight depends on the object’s surface texture. The smoother the surface texture, the greater the perceived weight. We suggest that a smoother object is judged to be heavier because the grip force, normal to the surface, required to prevent it from slipping is greater. The possibility of there being an influence of surface texture per se is excluded by a second experiment that employed a variant of the precision grip in which the thumb supports the weight of the object from underneath. With the grip oriented in this way, there is no need to match grip force to surface texture and, under these conditions, there is no effect of surface texture on weight perception. In the first two experiments, the test and comparison weights were lifted successively by the same hand. In a third experiment, the effect of surface texture was replicated for sequential lifts made with separate hands. Thus, the effect is not restricted to comparisons made with the same hand.  相似文献   
24.
Forty-two children (ages 6 to 12 years old) with moderate mental retardation to borderline intellectual functioning were studied in a laboratory playroom setting to determine whether children identified as ADHD (attention deficit hyperactivity disorder) or controls differed on activity and attentional measures. Children with ADHD were further divided into ADHD + conduct problems (ADHD + CD) and ADHD-only subgroups (with an ADHD-combined group comprising children of both subgroups). An interval recording system was used to code observations of independent play and a restricted academic task. Results indicated that the ADHD-combined group was significantly more vocal and engaged in a significantly greater number of toy changes than controls during independent play. Significant group differences were also noted during the restricted academic task, with the ADHD-combined and ADHD + CD groups more off-task and engaging in a greater number of toy touches than controls. Discriminant analyses found independent play measures to predict group membership in 70 percent of cases (ADHD-combined vs. controls), but in only 64 percent of cases using measures from the restricted academic task. No significant findings resulted when the ADHD subjects were further divided into two subgroups. Despite some inconsistent findings, such laboratory-based observations may be of value in the diagnosis of ADHD in children with moderate mental retardation to borderline intellectual functioning.  相似文献   
25.
The “factor” analyses published by Schultz, Kaye, and Hoyer (1980) confused component and factor analysis and led in this case as in many others to unwarranted conclusions. They used component analysis to develop factor models that were subjected to restricted (confirmatory) maximum likelihood analysis, but the final models for which good fits with the observed correlations were obtained were not common factor models. They were, however, discussed as such and conclusions drawn accordingly. When their correlation matrices are analyzed by the principal factors method, two factors are sufficient to account for the intercorrelations. These two factors generally support the a priori expectation of a difference between intelligence tasks and spontaneous flexibility tasks. They are also quite similar in younger and older subjects, when similarity is judged in terms of factor pattern. Factor loadings for the younger subjects, however, are much smaller than expectations based on the respective ranges of talent in the two groups of subjects or on past experience with similar tests in undergraduate student populations.  相似文献   
26.
Accuracy in the judgment of in-group and out-group variability   总被引:2,自引:0,他引:2  
The accuracy of in-group and out-group variability judgments was examined by comparing those judgments with the variability of self-ratings provided by random samples of group members. Following Park and Judd (1990), perceptions of both group dispersion and group stereotypicality were examined. Accuracy was examined both by within-subject sensitivity correlations and by simple discrepancies between perceived and actual variability estimates. In-group-out-group differences in sensitivity were shown, particularly for judgments of stereotypicality. These differences were related to differences in the degree to which out-group variability is underestimated relative to in-group variability (i.e., the out-group homogeneity effect). Out-group stereotypicality judgments were overestimated, supporting the view that out-group stereotypes are overgeneralizations. Whether dispersion judgments were over- or underestimated depended on their measurement.  相似文献   
27.
This paper outlines the theoretical influences that have led to our use of a consultation approach to work with children and families. Winnicott's notion of therapeutic consultation, the narrative approach in family therapy, the use of letters in therapeutic work and the two-plus-one model of therapeutic contact are discussed. A model of the consultation interview and process is presented together with examples of consultation letters responding to typical client expectations of the process.  相似文献   
28.
Differential-approach tendencies of individual incubator-hatched chickens and Japanese quail were assayed using one exemplar of each of the species maternal calls in a simultaneous-choice paradigm. Within 24 hr after hatching, the birds received several short periods of exposure to rotating mounts of an adult female chicken and quail, which emitted the species-appropriate call. All birds were then tested with calls alone over the following 2 to 4 days. The test stimuli were played from speakers located behind pressure-sensitive panels so that approach behavior was recorded when a bird pushed against one of the panels. Both the chickens and the quail, as groups, spent significantly more time attempting to approach the exemplar of their own species maternal call, although there was considerable variation in the magnitude of the approach difference among individuals within each species. Sources of variation in preference scores are analyzed, and a simulation is used to interpret individual differences in response scores. This type of preference test is useful for a number of applications, notably for studying the behavior of quail-chick nervous system chimeras.  相似文献   
29.
Using the method of paired comparisons, pairs of simultaneous horizontal or vertical lines, with one line above and one below or one on the left and one on the right of a fixation point, respectively, were presented tachistoscopically for length comparison. Space errors were found to have a pattern similar to that of time errors. The tendency to guess the comparative response from the absolute magnitude of stimuli is proposed as a basis for time and space errors. Manipulation of attentional scanning, which implies a more frequent usage of this guessing strategy for one of the two lines in a pair, was shown to affect space errors.  相似文献   
30.
Two naive human observers were conditioned to report on the slant of a 3.8-cpd sinusoidal grating viewed monocularly with a light-adapted eye and presented at various orientations extending from ?45 to +135 deg. The procedures used yielded a baseline measure of performance and measures obtained during conditioning, extinction, and reconditioning of the tilt-naming response. Both subjects learned rapidly, achieving a level of performance that permits efficient measurement of meridional differences in perceived orientation Ithe oblique effect) at a large number of angles.  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