全文获取类型
收费全文 | 16879篇 |
免费 | 1853篇 |
国内免费 | 5篇 |
出版年
2021年 | 169篇 |
2020年 | 274篇 |
2019年 | 596篇 |
2018年 | 583篇 |
2017年 | 718篇 |
2016年 | 721篇 |
2015年 | 575篇 |
2014年 | 585篇 |
2013年 | 1857篇 |
2012年 | 755篇 |
2011年 | 660篇 |
2010年 | 569篇 |
2009年 | 548篇 |
2008年 | 638篇 |
2007年 | 549篇 |
2006年 | 505篇 |
2005年 | 482篇 |
2004年 | 447篇 |
2003年 | 430篇 |
2002年 | 491篇 |
2001年 | 338篇 |
2000年 | 283篇 |
1999年 | 251篇 |
1998年 | 185篇 |
1997年 | 180篇 |
1996年 | 165篇 |
1995年 | 178篇 |
1994年 | 153篇 |
1993年 | 162篇 |
1992年 | 182篇 |
1991年 | 190篇 |
1990年 | 161篇 |
1989年 | 161篇 |
1988年 | 141篇 |
1987年 | 134篇 |
1986年 | 134篇 |
1985年 | 160篇 |
1984年 | 169篇 |
1983年 | 175篇 |
1982年 | 180篇 |
1981年 | 189篇 |
1980年 | 152篇 |
1979年 | 191篇 |
1978年 | 199篇 |
1977年 | 186篇 |
1976年 | 165篇 |
1975年 | 186篇 |
1974年 | 176篇 |
1973年 | 144篇 |
1972年 | 124篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Spatial frequencies and the cerebral hemispheres: contrast sensitivity, visible persistence, and letter classification 总被引:1,自引:0,他引:1
The hypothesis that the two cerebral hemispheres are specialized for processing different visual spatial frequencies was investigated in three experiments. No differences between the left and right visual fields were found for: (1) contrast-sensitivity functions measured binocularly with vertical gratings ranging from 0.5 to 12 cycles per degree (cpd); (2) visible persistence durations for 1- and 10-cpd gratings measured with a stimulus alternation method; and (3) accuracy (d') and reaction times to correctly identify digitally filtered letters as targets (L or H) or nontargets (T or F). One significant difference, however, was found: In Experiment 3, a higher decision criterion (beta) was used when filtered letters were identified in the right visual field than when they were identified in the left. The letters were filtered with annular, 1-octave band-pass filters with center spatial frequencies of 1, 2, 4, 8, and 16 cpd. Combining four center frequencies with three letter sizes (0.5 degrees, 1 degree, and 2 degrees high) made some stimuli equivalent in distal spatial frequency (cycles per object) and some equivalent in proximal spatial frequency (cycles per degree). The effective stimulus in the third experiment seemed to be proximal spatial frequency (cycles per degree) not distal (cycles per object). We conclude that each cerebral hemisphere processes visual spatial frequency information with equal accuracy but that different decision rules are used. 相似文献
102.
Mark D. Rapport Sheila O. Quinn George J. DuPaul Eugene P. Quinn Kevin L. Kelly 《Journal of abnormal child psychology》1989,17(6):669-689
This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic. 相似文献
103.
Anthony Spirito James Overholser Lori J. Stark 《Journal of abnormal child psychology》1989,17(2):213-221
This study investigated the most common precipitants of adolescent suicide attempts and the strategies used to cope with such problems. Adolescent suicide attempters were compared with both distressed and nondistressed nonsuicidal adolescents on problems reported and coping strategies utilized. All three groups reported four problems as occurring most frequently: school, parents, friends, or boyfriend/girlfriend. The suicide attempters and distressed controls reported problems with parents more frequently than did nondistressed controls, while this latter group reported problems at school more frequently than did suicide attempters or distressed controls. Suicide attempters used social withdrawal, problem solving, and emotional regulation more than did nondistressed controls, but not more frequently than distressed controls. Distressed controls used wishful thinking and resignation more than did suicide atempters. Results are discussed in terms of the similarities between suicide attempters and nonsuicidal distressed adolescents and the need to more closely investigate specific subgroups of suicide attempters. 相似文献
104.
Semantic priming in a lexical decision task was investigated with concurrent pretarget and posttarget primes. The posttarget prime also served as a pattern mask of the lexical decision target. Forward priming is defined as the presence of a semantically related pretarget prime and an unrelated posttarget prime. Backward priming is defined as the presence of a semantically related posttarget prime and an unrelated pretarget prime. Forward and backward priming were compared both when the nonword foils were "legal" and when they were "illegal" with respect to English orthography. Predictions were derived for two general approaches to word recognition: spreading-activation and expectancy-set theories. Both approaches assume that word representations occupy distinct, nonoverlapping locations in memory. Backward-prime facilitation was equivalent to forward-prime facilitation when nonword foils were illegal; however, backward-prime facilitation was not significant when nonword foils were legal. These results challenge both approaches. The proposed solution uses semantic-space (distributed) representations that are functionally unitized by a resonant matching (verification) process. 相似文献
105.
106.
Bengt O. Muthén 《Psychometrika》1989,54(3):385-396
The problem of detecting instructional sensitivity (item basis) in test items is considered. An illustration is given which shows that for tests with many biased items, traditional item bias detection schemes give a very poor assessment of bias. A new method is proposed instead. This method extends item response theory (IRT) by including item-specific auxiliary measurement information related to opportunity-to-learn. Item-specific variation in measurement relations across students with varying opportunity-to-learn is allowed for.This paper was presented at the 1987 AERA meeting in Washington, DC. This research was supported by grant OERI-G-86-003 from the Office of Educational Research and Improvement, Department of Education. The author thanks Michael Hollis and Chih-fen Kao for valuable research assistance, and appreciates valuable comments made by an anonymous reviewer. 相似文献
107.
Recall by expert medical practitioners and novices as a record of processing attention 总被引:1,自引:0,他引:1
G R Norman L R Brooks S W Allen 《Journal of experimental psychology. Learning, memory, and cognition》1989,15(6):1166-1174
Using recall of clinical protocols as a measure of expertise in medicine has yielded disappointingly small effects. Experiments using recall of clinical laboratory data are presented to provide an explanation. In one experiment, subjects either deliberately memorized or first diagnosed and then were incidentally asked for memory. With incidental instructions, experts recalled over twice as much data as did students, but with memorization instructions, student performance approximated that of experts. Experts also showed a large advantage over students in incidental recall of data that were not relevant to the problem solution. These results suggest that expert processing in this "discrete, independent inputs" domain requires effortful analysis with minimal reliance on default values, rather than relatively effortless pattern perception reported in highly visual areas of expertise. For this area, intentional memory is a misleading measure of expertise. However, incidental memory is a valuable measure of processing during diagnosis. 相似文献
108.
Current models of goal setting often fail to consider the potential negative effects of goal programs. Control over goal difficulty levels may be an important source of personal control in the workplace and psychological reactance may result from a shift in control over the setting of goals. The present experiment examined the effects of initial goal origin (assigned or self-set) and shifted goal origin (shifted or not shifted) on goal acceptance and attainment over two trial blocks of a verbal task. Several hypotheses based on psychological reactance theory were tested in a laboratory experiment with 160 college undergraduates. Overall analyses revealed significant interactions for goal acceptance and goal attainment over trial blocks. Simple effect analyses isolated this interaction for both dependent variables in a disordinal crossover pattern for the shifted origin groups over trial blocks, as expected. The discussion focuses on fitting these results into the current program guiding goal-setting research and on suggesting future avenues of research. Some implications for the application of goal setting are also discussed. 相似文献
109.
Responses to graphic horror films have been shown to be modified by a number of personality variables, and in particular, by gender-specific rules for social conduct. In earlier horror research it has been assumed that gender-specific responses are largely determined by biological gender. More recent research has focused on psychological patterns of gender identity that often transcend biological gender lines. This investigation sought clarification by examining the impact of individuals' self-perceived gender role and other personality characteristics on affective responses to horror. Subjects' perceptions of how same- and opposite-gender peers would respond to such materials were also assessed. Consistent with theoretical expectations, the findings revealed strong effects on the estimation of opposite-gender target's reactions as a function of both the rater's gender role characteristics and biological gender. Other personality factors were found to influence responses to horror only marginally, however. The results are discussed in terms of the gender role socialization model of affect. 相似文献
110.
James J. Jupp 《Counselling psychology quarterly》1989,2(4):441-450
Neurolinguistic programmers claim that individuals have preferred (primary) representational systems. These may be auditory, visual or kinesthetic and determine how a person views/deals with the world. Systems can be identified by observation of eye movements. In workshops programmers demonstrated strong associations between eye movements following questioning and types of questions and eye movement categories (assumed to identify systems) and other assessments of systems. Studies have evaluated these ‘workshop’ associations and found little support for their general occurrence. In these studies, it is possible that eye movements following questioning were influenced by artifacts which influence predicted association between these and other variables. An attempt was made to exclude these artifacts in this study. Except for subjects who had attended neurolinguistic workshops, results supported those obtained elsewhere. Possibly, associations in workshops occur as a result of expectational-contextual variables. 相似文献