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   102742篇
  免费   4239篇
  国内免费   37篇
  2020年   1107篇
  2019年   1366篇
  2018年   1892篇
  2017年   1955篇
  2016年   2056篇
  2015年   1479篇
  2014年   1755篇
  2013年   8342篇
  2012年   3288篇
  2011年   3411篇
  2010年   2103篇
  2009年   2119篇
  2008年   2974篇
  2007年   2980篇
  2006年   2731篇
  2005年   2371篇
  2004年   2282篇
  2003年   2173篇
  2002年   2212篇
  2001年   3289篇
  2000年   3150篇
  1999年   2381篇
  1998年   1175篇
  1997年   1043篇
  1996年   1080篇
  1995年   986篇
  1993年   967篇
  1992年   1999篇
  1991年   1868篇
  1990年   1882篇
  1989年   1731篇
  1988年   1689篇
  1987年   1605篇
  1986年   1648篇
  1985年   1704篇
  1984年   1443篇
  1983年   1286篇
  1982年   942篇
  1979年   1515篇
  1978年   1109篇
  1975年   1220篇
  1974年   1355篇
  1973年   1465篇
  1972年   1217篇
  1971年   1143篇
  1970年   1018篇
  1969年   1036篇
  1968年   1303篇
  1967年   1173篇
  1966年   1059篇
排序方式: 共有10000条查询结果,搜索用时 390 毫秒
971.
Auditory sequential memory subtests of the Wechsler Preschool and Primary Scale of Intelligence and the McCarthy Scales of Children's Abilities were administered individually to 20 normal preschool children. Poor performance on the McCarthy words/sentences subtest suggests retention difficulties associated with isolated words in the absence of linguistic context. Correlations of only moderate strength and large unexplained variance indicate poor predictability between subtests despite similarities in content and procedural details.  相似文献   
972.
The purpose of this study was to determine whether videotaped demonstrations of an action which displayed only the motion pattern of a model's limb as compared with one which showed both form and motion provide sufficient information for modelling a given pattern of movement. Video-demonstrations of an arm-movement sequence which ended with a throwing action were shown to adult subjects whose task was to model precisely what they saw. Each demonstration lasted 6 sec. and was shown 6 times. It portrayed the arm of a model, who held a small ball, performing a sequence of movements (flexion and extension of the elbow) which ended in the ball being thrown about 2.5 m with a 'darts-style' action. Three types of demonstration were presented: one showed the whole arm in dark clothing against a light-coloured background, another showed the arm as the relative motion of patches of light situated at the shoulder, elbow, and wrist joints, and the third showed the arm as the relative motion of the upper and lower segments of the arm represented by strips of light-reflectant material. These were the stimuli for the between-groups experimental conditions. Goniometry techniques were used to compare the performance of subjects relative to the model. Analysis showed that the order of the preparatory sequence was correctly produced after 4 trials under all conditions. Range of arm movement in projecting the ball closely approximated that of the model after 4 trials in all conditions. The time taken for the arm to project the ball remained constant across trials under all conditions and was always slower than the demonstrated cadence.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
973.
A diverse set of findings from recent research suggests the value of visual imagery techniques in clinical practice.  相似文献   
974.
The effect of prohibiting the use of a preshot routine on free-throw shooting in competitive situations was investigated. 25 male high school basketball players were instructed to attempt 50 free throws alternating in blocks of 10 between the use of their preshot routine and shooting without it. To make the situation competitive, subjects were run in groups of five and their performance was recorded on a large easel placed to the side of the free-throw line. A significantly larger number of baskets were made in the preshot routine condition than without the routine. A competitive situation led to a greater decrement in baskets than had been reported in 1986 by Lobmeyer and Wassermen during noncompetitive free-throw shooting.  相似文献   
975.
Direct and indirect theories of perception differ on whether form perception depends on higher order invariants or on features in the retinal image. The present paper describes a demonstration that an object can be recognized through a higher order pattern (dynamic occlusion) without any of the object's features being displayed. Stimuli consist of computer stimulations of black wireframe objects moving in front of, and occluding, a random layout of point lights on a black background. In this way, no single videoframe of the stimuli displays any of the object's features, and motion of the amodal object in front of the light points is necessary for the form to become visible. The forms can also be recognized when isoluminous colours are used for background and point lights. Finally, it is noted that, if the observer can actively control the motion of the object, e.g., by moving a computer mouse, recognition is enhanced as in Gibson's (1962) experiment on active touch.  相似文献   
976.
Two research questions pertaining to the applicant age bias effect were addressed in this study: the effect of age-related information exposure on selection decisions and the issue of between-sample generalizability with reference to the age bias effect. Manager and student selectors made selection decisions after viewing one videotape of a simulated selection interview of either an old or a young job applicant. Before viewing the interview tape, half of each subject group was given an item of age-related information and the other half was given neutral information. The results showed that, under the neutral information condition, managers preferred hiring the young applicant for the low-status job, and students favored the old candidate for the high-status position. Under the age-related information condition, managers shifted to favoring the old candidate for the low-status job, and students preferred the young applicant for both the low- and high-status positions. Age discrimination in selection decisions and the lack of external validity of student results in selection research are then discussed.  相似文献   
977.
This study compared the performance on the WAIS and WAIS--R of 21 mentally retarded adults residing in an Intermediate Care Facility. Tests were administered in one order, the WAIS initially and the WAIS--R second, with approximately two years between testings. Significant differences were found on the WAIS and WAIS--R for Verbal, Performance and Full Scale IQs. This finding contrasts with the differences between the measures as reported in the WAIS--R manual.  相似文献   
978.
As more children with cancer survive, the importance of facilitating school reintegration as a part of maximizing the quality of life has become evident. Workshops have been presented to school personnel to acquaint them with the issues facing cancer patients and their families, but there are gaps in our knowledge of what school personnel really need or want to know. In this study, 18 teachers of children with cancer and 15 teachers with no prior contact with students with cancer completed a questionnaire designed to assess needs, beliefs, and priorities with regard to working with cancer patients in the classroom. Significant findings included: (a) a consensus that a certain core of information about medical/psychological issues would be useful, and presentation of such information by psychologists and medical personnel working with such families would be optimal; (b) teachers having cancer patients as students were less likely to see the adaptation of siblings as an important issue; (c) teachers associated working with a student with cancer with less stress and demands on their time than predictable from previous studies; and (d) cancer patients as a whole were rated as having fewer behavioral, emotional, and learning problems than randomly selected students without a major illness, suggesting a "halo effect" or contradiction of some literature. Preliminary findings are detailed and implications are discussed for those attempting to help teachers facilitate students' adjustment to school following diagnosis and treatment of cancer.  相似文献   
979.
19 pairs of third grade children from intact and single-parent families matched for sex, intellectual ability, and academic achievement were administered a brief self-concept measure. Teachers and parents rated the students' self-concept on similar measures. There were no significant differences in scores between the groups; however, within each group the teachers and parents consistently overestimated students' self-esteem.  相似文献   
980.
An Extended Two-Way Euclidean Multidimensional Scaling (MDS) model which assumes both common and specific dimensions is described and contrasted with the standard (Two-Way) MDS model. In this Extended Two-Way Euclidean model then stimuli (or other objects) are assumed to be characterized by coordinates onR common dimensions. In addition each stimulus is assumed to have a dimension (or dimensions) specific to it alone. The overall distance between objecti and objectj then is defined as the square root of the ordinary squared Euclidean distance plus terms denoting the specificity of each object. The specificity,s j , can be thought of as the sum of squares of coordinates on those dimensions specific to objecti, all of which have nonzero coordinatesonly for objecti. (In practice, we may think of there being just one such specific dimension for each object, as this situation is mathematically indistinguishable from the case in which there are more than one.)We further assume that ij =F(d ij ) +e ij where ij is the proximity value (e.g., similarity or dissimilarity) of objectsi andj,d ij is the extended Euclidean distance defined above, whilee ij is an error term assumed i.i.d.N(0, 2).F is assumed either a linear function (in the metric case) or a monotone spline of specified form (in the quasi-nonmetric case). A numerical procedure alternating a modified Newton-Raphson algorithm with an algorithm for fitting an optimal monotone spline (or linear function) is used to secure maximum likelihood estimates of the paramstatistics) can be used to test hypotheses about the number of common dimensions, and/or the existence of specific (in addition toR common) dimensions.This approach is illustrated with applications to both artificial data and real data on judged similarity of nations.  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