全文获取类型
收费全文 | 7159篇 |
免费 | 117篇 |
专业分类
7276篇 |
出版年
2021年 | 64篇 |
2020年 | 98篇 |
2019年 | 111篇 |
2018年 | 126篇 |
2017年 | 124篇 |
2016年 | 139篇 |
2015年 | 109篇 |
2014年 | 145篇 |
2013年 | 758篇 |
2012年 | 213篇 |
2011年 | 263篇 |
2010年 | 163篇 |
2009年 | 186篇 |
2008年 | 208篇 |
2007年 | 233篇 |
2006年 | 194篇 |
2005年 | 194篇 |
2004年 | 204篇 |
2003年 | 200篇 |
2002年 | 220篇 |
2001年 | 107篇 |
2000年 | 86篇 |
1999年 | 96篇 |
1998年 | 116篇 |
1997年 | 129篇 |
1996年 | 106篇 |
1995年 | 96篇 |
1994年 | 93篇 |
1993年 | 120篇 |
1992年 | 111篇 |
1991年 | 73篇 |
1990年 | 78篇 |
1989年 | 83篇 |
1988年 | 76篇 |
1987年 | 86篇 |
1986年 | 70篇 |
1985年 | 74篇 |
1984年 | 97篇 |
1983年 | 93篇 |
1982年 | 104篇 |
1981年 | 96篇 |
1980年 | 97篇 |
1979年 | 86篇 |
1978年 | 110篇 |
1977年 | 107篇 |
1976年 | 92篇 |
1975年 | 108篇 |
1974年 | 90篇 |
1973年 | 67篇 |
1971年 | 62篇 |
排序方式: 共有7276条查询结果,搜索用时 0 毫秒
141.
Craig A. Smith Carolyn J. Dobbins Kenneth A. Wallston 《Journal of applied social psychology》1991,21(15):1218-1244
Chronic illnesses such as rheumatoid arthritis (RA) have been linked to poor psychological adjustment, although individual differences in this relationship have been observed. This study examines the role of perceived competence as a mediator between RA and adjustment. Persons with RA (N= 208) were surveyed three times at 6-month intervals concerning several potential antecedents of adjustment (pain, psychosocial impairment, social support, and control beliefs), self-perceived level of competence, and level of adjustment (life satisfaction and depressive symptomatology). Within each observational period strong evidence was obtained for perceived competence as a mediator of adjustment. Longitudinally (across the year) the data were consistent with a mediational model, but strong evidence establishing mediation was not obtained. Implications of these findings, and the importance of examining the role of perceived competence in adaptation to chronic illness, are discussed. 相似文献
142.
William F. Chaplin 《Journal of personality》1991,59(2):143-178
143.
Previous research (Hall, Scholnick, & Hughes, 1987) suggested that cognitive word meanings denote six increasingly abstract and complex cognitive processes. In this paper, we further investigated two interrelated aspects of this framework. A set of 36 conversations with children aged 4:5 to 5 provided the data. In Study 1, issues related to the optimal ordering of levels were examined by comparing the original sequence with a restructured model. In Study 2, the hypothesis that, in addition toknow, other polysemous cognitive internal state words would be hierarchically organized was tested. The findings lent support to the restructured model, but rejected the hypothesis that polysemous words within the domain were characterized by equivalent,hhierarchically organized levels. We conclude by proposing that cognitive internal state words were related by complementarity of levels rather than equivalence.The research on which this paper is based was supported by a grant from the Carnegie Corporation of New York to William S. Hall. Data analysis was supported by the Computer Science Center at the University of Maryland, College Park. 相似文献
144.
Two experiments were performed that involved an initial word-identification task in which the acoustic signal was degraded by either 50% or 60% compression of the recorded words. A control group was tested at the original recording rate (0% compression). The compression manipulation was successful in increasing the number of identification errors. During the second stage of the experiments, words were read at a normal rate. In Experiment 1, the subjects indicated whether each word had appeared on the prior list, and in Experiment 2, the subjects estimated the number of times each word had been read on the prior list. The false-negative rate decreased and frequency ratings increased as a function of the number of prior presentations (one, two, or three) of the target words. The most interesting result was that the effect of repetitions was present even for words that had been misperceived. 相似文献
145.
William E. MacLean Jr. David N. Ellis Holly N. Galbreath Leslie F. Halpern Alfred A. Baumeister 《Journal of abnormal child psychology》1991,19(3):319-330
The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990. 相似文献
146.
In this paper we consider several issues about single-patient versus syndrome-based research in response to E. Zurif, D. Swinney, and J. A. Fodor's (1991, Brain and Cognition, 16, 198-210) criticism of A. Caramazza and W. Badecker (1989, Brain and Cognition, 10, 256-295). We argue that these authors have failed to provide convincing arguments in favor of syndrome-based research. In particular, we show that the specific example--a study by D. Swinney, E. Zurif, and J. Nicol (1989, Journal of Cognitive Neurosciences, 1, 25-37)--given by these authors as a demonstration of the usefulness of syndrome-based research to inform theories of normal language processing does not in fact serve this purpose. 相似文献
147.
William S. Pooler 《Sex roles》1991,25(9-10):569-576
In both 1985 and 1988, college student preferences for the sex of an only child were examined using social surveys. For both years, it was found that male students strongly prefer a male child, but that female students moderately prefer a female child. Gender of respondent accounted for most of the sex preference difference. The sex role attitude of agreement with having the wife retain her own name was the only other variable significantly related to sex preference. It is argued that differing male-female role expectations for women as wives and mothers partly explained the gender differences in sex preference for a child. 相似文献
148.
William Irons 《Zygon》1991,26(1):49-89
Abstract. This paper presents and criticizes. Alexander's evolutionary theory of morality (1987). Earlier research, on which Alexander's theory is based, is also reviewed. The propensity to create moral systems evolved because it allowed ancestral humans to limit conflict within cooperating groups and thus form larger groups, which were advantageous because of intense between-group competition. Alexander sees moral codes as contractual, and the primary criticism of his theory is that moral codes are not completely contractual but also coercive. Ways of evaluating Alexander's theory as well as modified versions of it are discussed. 相似文献
149.
William P. Hetrick Robert C. Isenhart Derek V. Taylor Curt A. Sandman 《Behavior research methods》1991,23(1):66-71
A software program written to collect real-time, observational data is described. The flexible program allows customized behavior codes and observational durations and simultaneously records both timed and counted events. The data are collected by means of single keystrokes, automatically stored to disk with 100th of a second resolution and summarized for each observational session. The program’s database files are dBASE III PLUS compatible and may be browsed, edited, or converted to ASCII files from the program’s main menu. Field testing demonstrated the efficiency and interobserver reliability of the program (for frequency,r=0.81; for durational behaviors,rs=0.89 and 0.96). The software operates on IBM XT/AT/PS 2s and most clones with PC/MS DOS version 2.0 or greater. 相似文献
150.
When measuring the same variables on different occasions, two procedures for canonical analysis with stationary compositing weights are developed. The first, SUMCOV, maximizes the sum of the covariances of the canonical variates subject to norming constraints. The second, COLLIN, maximizes the largest root of the covariances of the canonical variates subject to norming constraints. A characterization theorem establishes a model building approach. Both methods are extended to allow for Cohort Sequential Designs. Finally a numerical illustration utilizing Nesselroade and Baltes data is presented.The authors wish to thank John Nesselroade for permitting us to use the data whose analysis we present. 相似文献