全文获取类型
收费全文 | 61509篇 |
免费 | 2512篇 |
国内免费 | 21篇 |
出版年
2020年 | 588篇 |
2019年 | 779篇 |
2018年 | 1066篇 |
2017年 | 1070篇 |
2016年 | 1143篇 |
2015年 | 828篇 |
2014年 | 967篇 |
2013年 | 4557篇 |
2012年 | 1826篇 |
2011年 | 1994篇 |
2010年 | 1233篇 |
2009年 | 1223篇 |
2008年 | 1780篇 |
2007年 | 1787篇 |
2006年 | 1632篇 |
2005年 | 1447篇 |
2004年 | 1333篇 |
2003年 | 1258篇 |
2002年 | 1348篇 |
2001年 | 2004篇 |
2000年 | 1985篇 |
1999年 | 1491篇 |
1998年 | 728篇 |
1997年 | 635篇 |
1996年 | 634篇 |
1993年 | 563篇 |
1992年 | 1259篇 |
1991年 | 1176篇 |
1990年 | 1147篇 |
1989年 | 1048篇 |
1988年 | 1031篇 |
1987年 | 987篇 |
1986年 | 1057篇 |
1985年 | 1070篇 |
1984年 | 893篇 |
1983年 | 816篇 |
1982年 | 590篇 |
1981年 | 588篇 |
1979年 | 957篇 |
1978年 | 689篇 |
1975年 | 786篇 |
1974年 | 838篇 |
1973年 | 933篇 |
1972年 | 786篇 |
1971年 | 739篇 |
1970年 | 657篇 |
1969年 | 685篇 |
1968年 | 876篇 |
1967年 | 798篇 |
1966年 | 667篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
301.
Different patterns of cognitive slowing produced by Alzheimer's disease and normal aging 总被引:2,自引:0,他引:2
Aging has previously been shown to produce a generalized proportional slowing of all cognitive operations. In contrast, the present results suggested that Alzheimer's disease produces a disproportionate reduction in the speed with which patients carry out one or more mental operations. The tasks that demented patients found particularly difficult involved either a self-directed search of their lexicon or the use of familiarity information. 相似文献
302.
Adult age differences in the effects of sentence context and stimulus degradation during visual word recognition 总被引:1,自引:0,他引:1
D J Madden 《Psychology and aging》1988,3(2):167-172
I investigated adult age differences in the efficiency of feature-extraction processes during visual word recognition. Participants were 24 young adults (M age = 21.0 years) and 24 older adults (M age = 66.5 years). On each trial, subjects made a word/nonword discrimination (i.e., lexical decision) regarding a target letter-string that was presented as the final item of a sentence context. The target was presented either intact or degraded visually (by the presence of asterisks between adjacent letters). Age differences in lexical decisions speed were greater for degraded targets than for intact targets, suggesting an age-related slowing in the extraction of feature-level information. For degraded word targets, however, the amount of performance benefit provided by the sentence context was greater for older adults than for young adults. It thus appears that an age-related deficiency at an early stage of word recognition is accompanied by an increased contribution from semantic context. 相似文献
303.
Structural integration of the Affect Balance Scale and the Life Satisfaction Index A: race, sex, and age differences 总被引:1,自引:0,他引:1
In this research we examined race, sex, and age differences in the factorial structure of Liang's (1985) model of subjective well-being that integrates the Affect Balance Scale and the Life Satisfaction Index A. In particular, we viewed the covariance structure of the items as a function of several parameter matrices. We analyzed the factorial invariance by testing hypotheses involving the equivalence constraints of one or more parameter matrices with regard to the following: White and Black subsamples, men and women, and the young-old and the old-old. Data for the research came from the 1974 Harris National Council on Aging Survey, Myths and Reality of Aging in America. Analysis of covariance structures, or LISREL, was used to assess the factorial invariance. Replicated race differences were found in the factorial structure, but sex and age differences were not found. Consistent race differences were found for the second-order factor loadings for negative affect. 相似文献
304.
We evaluated the effects of an 8-week progressive muscle-relaxation therapy regimen on the headache activity of 10 elderly tension-headache subjects. Posttreatment assessment at 3 months revealed significant decreases in overall headache activity (50% or greater) in 7 subjects. Significant clinical or statistical prepost differences, or both, were also found for the number of headache-free days, peak headache activity, and medication index. This is the first prospective study of tension headache in an elderly population, and, unlike previous retrospective studies, it suggests that relaxation therapy may be an effective intervention in the treatment of such headaches. 相似文献
305.
Anthony J. Goreczny Phillip J. Brantley Ray R. Buss William F. Waters 《Journal of psychopathology and behavioral assessment》1988,10(3):259-267
Although stress and anxiety have long been assumed to play an exacerbatory role in asthma, no study has systematically documented that daily exacerbations of asthma symptoms are related to stress and/or anxiety. In this study, 24 airways obstruction patients (12 asthmatics and 12 chronic obstructive pulmonary disease patients) were instructed to monitor the severity of daily respiratory symptoms. In addition, subjects recorded their daily anxiety level and the number and perceived impact of daily stressors. The results showed that although there were differences between high- and low-stress days for both groups, there were no differences between groups on symptom severity or between high- and low-anxiety days, as measured by the State-Trait Anxiety Inventory (STAI). Thus, although the number and impact of daily stressors were found to be directly associated with the severity of asthma symptoms, anxiety does not appear to have a direct role in the exacerbation of asthma. The findings failed to support the anxiety theory of asthma but provided an explanation for the poor results obtained in previous treatment studies which employed anxiety management with asthmatics. 相似文献
306.
Gregory J. Boyle 《Journal of psychopathology and behavioral assessment》1988,10(3):205-215
Two multidimensional mood-state inventories, the Profile of Mood States (POMS) and the Eight State Questionnaire (8SQ), were administered to 289 Australian college undergraduates. Intercorrelations for the combined 14 subscales were subjected to a higher-order factor analysis in order to elucidate the central clinical states within the mood-state sphere. Results suggested four major state dimensions pertaining to Neuroticism, Hostility/Anger, Vigor, and a combined Extroversion/Arousal-Fatigue entity. Both three- and five-factor solutions were taken out for comparative purposes. Furthermore, separate higher-order factorings of the POMS on normative samples of 350 male and 650 female psychiatric outpatients were conducted, corroborating three of the four central state dimensions, at least in the case of females. The implications of these findings for behavioral assessment are discussed.This study was supported by a Research Development Grant awarded to the author by the University of Melbourne. 相似文献
307.
Johnston JM 《The Behavior analyst / MABA》1988,11(1):1-9
A comparison study is an experiment whose primary purpose is to compare directly (regardless of experimental design) at least two different procedures for changing behavior or two or more components of such a procedure. This paper argues that, in spite of their popularity, such studies typically lead to inappropriate inferences with poor generality based on improper evidence gathered in support of the wrong question, thus wasting the limited experimental resources. The discussion considers problems concerning the functions of comparison studies, the nature of the comparisons that are attempted, the generality of their findings, and the limited role that they can play in technological research. 相似文献
308.
309.
Ellen J. Frank 《Sex roles》1988,19(1-2):107-118
310.