全文获取类型
收费全文 | 7205篇 |
免费 | 747篇 |
国内免费 | 314篇 |
专业分类
8266篇 |
出版年
2024年 | 33篇 |
2023年 | 161篇 |
2022年 | 120篇 |
2021年 | 134篇 |
2020年 | 348篇 |
2019年 | 331篇 |
2018年 | 305篇 |
2017年 | 328篇 |
2016年 | 290篇 |
2015年 | 220篇 |
2014年 | 275篇 |
2013年 | 835篇 |
2012年 | 145篇 |
2011年 | 260篇 |
2010年 | 223篇 |
2009年 | 296篇 |
2008年 | 342篇 |
2007年 | 372篇 |
2006年 | 379篇 |
2005年 | 318篇 |
2004年 | 288篇 |
2003年 | 215篇 |
2002年 | 182篇 |
2001年 | 126篇 |
2000年 | 106篇 |
1999年 | 120篇 |
1998年 | 99篇 |
1997年 | 75篇 |
1996年 | 58篇 |
1995年 | 59篇 |
1994年 | 45篇 |
1993年 | 47篇 |
1992年 | 46篇 |
1991年 | 25篇 |
1990年 | 25篇 |
1989年 | 41篇 |
1987年 | 19篇 |
1985年 | 130篇 |
1984年 | 127篇 |
1983年 | 110篇 |
1982年 | 93篇 |
1981年 | 68篇 |
1980年 | 74篇 |
1979年 | 67篇 |
1978年 | 99篇 |
1977年 | 58篇 |
1976年 | 45篇 |
1975年 | 31篇 |
1974年 | 24篇 |
1973年 | 28篇 |
排序方式: 共有8266条查询结果,搜索用时 8 毫秒
151.
152.
An Ames (1951, Psychological Monographs, 65(1, Whole No. 324)) static trapezoidal window, under monocular view, was used to test young infants' responsiveness to pictorial depth. When adults view this display monocularly with the smaller side of the window rotated toward them, they report that the orientation of the display becomes ambiguous: When the head is moved, the window may appear to be in the fronto-parallel plane or either side may appear closer. The 7-month-olds we tested appeared to experience a similar ambiguity; they reached to the near side of the rotated trapezoidal window with significantly less consistency or directedness than infants in a control group tested with a rotated object that lacked pictorial depth information. When 5-month-olds were tested, however, they reached with equal consistency to the closer side of the trapezoidal window and of the control display, apparently uninfluenced by the pictorial depth information available in the trapezoidal window. Thus, sensitivity to the pictorial information for depth that is present in the trapezoidal window appears to develop after the age of 22 weeks. 相似文献
153.
154.
The present study tested the hypothesis that individuals with the Type A coronary prone behavior pattern focus their attention more on important tasks, and less on trivial tasks than do Type B's. The study used a paradigm in which some subjects worked on math problems (important task) and rated intervening mood items (trivial task), whereas others rated mood items they were to memorize (important task) and worked on intervening math problems (trivial task). All subjects were later tested on recall of mood items. Results indicated that Type A's performed better on math problems and recalled more fatigue-related mood items when the task was important than when it was trivial; for Type B subjects, there was no difference in the number of math problems solved correctly or number of mood items recalled between important and trivial task conditions. Moreover, Type A's reported greater fatigue when mood recall was the important task than when math was the important task, whereas fatigue ratings of Type B's did not differ across these conditions. The findings suggest that Type A's suppress their attention to fatigue-related symptoms only when symptoms are not the objects of focus. 相似文献
155.
The experiment tested a prediction, derived from the lexicalist model of grammar (J. Bresnan 1978, in M. Halle, J. Bresnan, & G. A. Miller (Eds.), Linguistic theory and psychological reality, Cambridge, Mass.: MIT Press, pp. 1–59), that difficulty in accessing a verb from the lexicon should impair the generation of the associated to-complement clause while not significantly affecting the generation of word-independent constructions such as questions. Four aphasic subjects with word-finding difficulties but relatively high BDAE ratings on grammatical ability were examined. A modified story completion paradigm was used to elicit the favored constructions. Consistent with the hypothesis, all subjects showed greater difficulty in generating to-complements. 相似文献
156.
Meryl J. Wall C. Woodruff Starkweather Helen S. Cairns 《Journal of Fluency Disorders》1981,6(4):283-298
This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering. 相似文献
157.
Simple motor reaction times (right-handed) to tape-recorded consonant-vowel syllables were obtained from 12 subjects under two conditions of monotic stimulation: “expected” presentation (subject informed as to ear of presentation) and “random” presentation (ear of presentation varied randomly). Significantly faster left ear reaction times were obtained in the “expected” condition. The rank order of subjects' standard dichotic listening task scores correlated negatively with reaction time ear differences in the “expected” presentation condition. Results are discussed in terms of existing theories of response lateralization in simple reaction time tasks, and an expanded hypothesis is offered. Specifically, it is suggested that two or more distinct but potentially overlapping mechanisms may be responsible for observed asymmetries in monotic auditory perception. Both an attentional or lateralized motor response bias and an inherent lateralization of function may operate side by side, differentially activated by task demands, mode of stimulus presentation, and nature of stimuli. 相似文献
158.
Robert L. Hale 《Journal of School Psychology》1981,19(3):274-278
This study investigated the efficacy of predicting academic achievement as measured by the Wide Range Achievement Test using the factor scores of the Wechsler Intelligence Scale for Children-Revised as potential predictors. Both instruments were administered to 200 school children referred for psychological evaluations. Factor scores for the WISC-R were computed according to equations provided by Gutkin (1978). These factor scores then were regressed in a stepwise manner on the Reading, Spelling, and Arithmetic standard scores from the Wide Range Achievement Test. Stepwise regressions also were performed using the traditional Verbal and Performance IQs as the potential predictors. A comparison was made between the results obtained by use of the factors or the more common scores. The results indicated that the Freedom From Distractibility factor score significantly aided in the prediction of Reading and Spelling achievement and was of primary importance in predicting Arithmetic achievement. When the stepwise results using the different scores were contrasted, the factor scores accounted for appreaciably more variance in Arithmetic than did the traditional Verbal and Performance IQs. Derived regression equations are reported along with a discussion of the interpretability of the Freedom From Distractibility factor. 相似文献
159.
Effect of delay-interval stimuli on delayed symbolic matching to sample in the pigeon 总被引:4,自引:4,他引:0 下载免费PDF全文
In Experiment 1, food-deprived pigeons received delayed symbolic matching to sample training in a darkened Skinner box. Trials began with the illumination of the grain feeder lamp (no food sample), or illumination of this lamp, accompanied by the raising of the feeder tray (food sample). After a delay of a few seconds, the two side response keys were illuminated, one with red and one with green light, with positions counterbalanced over trials. Pecking the red (green) comparison produced grain reinforcement if the trial had started with food (no food); pecking red after a no-food sample or green after a food sample was not reinforced. Once matching performance was stable, four stimuli were presented during the delay interval, and their effects on matching accuracy were evaluated. Both illumination of the houselight and the center key with white geometric forms decreased matching accuracy, whereas presentation of a tone and vibration of the test chamber did not. In Experiment 2, pecking the red center key was reinforced with food according to a variable interval schedule. The effects of occasional brief presentations of the four stimuli used in the first experiment on ongoing pecking were assessed. The houselight and form disturbed key pecking, but the tone and vibration did not. Thus, stimuli that interfered with delayed matching also interfered with simple operant behavior. Implications of these results for theories of remembering are discussed. 相似文献
160.
Stimulus control of respondent and operant key pecking: A single key procedure 总被引:1,自引:1,他引:0 下载免费PDF全文
Marcucella H 《Journal of the experimental analysis of behavior》1981,36(1):51-60
Pigeons' responses to a uniformly illuminated response key were either reinforced on a variable-interval one-minute schedule of reinforcement or extinguished for one-minute periods. When 1.5 second signals were presented at the beginning of each component, so as to differentially predict reinforcement, the pigeons pecked at the signals, at rates higher than rates during the remainder of the component. When the brief signals were not differentially predictive of reinforcement, pecking in their presence decreased to near zero levels. Similar results were obtained with signals based upon colors and upon line orientations. Changes in rates of (unreinforced) pecking occurred during the signal whether pigeons responded differentially during the remainder of the component or not. Experiment II demonstrated that the presence of the signal correlated with extinction was not necessary for pecking to develop at the signal which preceded the component in which responding was intermittently reinforced. The experiments demonstrated a clear dissociation of respondent control from operant control of a response. In addition, operant behavior was shown to be relatively insensitive to differing rates of reinforcement, as compared to the sensitivity of respondent behavior to differing rates of reinforcement produced by the very same operant behavior. 相似文献