全文获取类型
收费全文 | 3344篇 |
免费 | 106篇 |
专业分类
3450篇 |
出版年
2021年 | 36篇 |
2020年 | 38篇 |
2019年 | 56篇 |
2018年 | 88篇 |
2017年 | 75篇 |
2016年 | 93篇 |
2015年 | 67篇 |
2014年 | 66篇 |
2013年 | 342篇 |
2012年 | 117篇 |
2011年 | 139篇 |
2010年 | 78篇 |
2009年 | 87篇 |
2008年 | 112篇 |
2007年 | 131篇 |
2006年 | 105篇 |
2005年 | 117篇 |
2004年 | 116篇 |
2003年 | 112篇 |
2002年 | 101篇 |
2001年 | 56篇 |
2000年 | 70篇 |
1999年 | 67篇 |
1998年 | 51篇 |
1997年 | 46篇 |
1996年 | 49篇 |
1995年 | 47篇 |
1994年 | 42篇 |
1993年 | 41篇 |
1992年 | 51篇 |
1991年 | 29篇 |
1990年 | 54篇 |
1989年 | 51篇 |
1988年 | 45篇 |
1987年 | 46篇 |
1986年 | 33篇 |
1985年 | 37篇 |
1984年 | 43篇 |
1983年 | 30篇 |
1982年 | 43篇 |
1981年 | 35篇 |
1980年 | 40篇 |
1978年 | 45篇 |
1977年 | 25篇 |
1976年 | 32篇 |
1975年 | 37篇 |
1974年 | 25篇 |
1973年 | 36篇 |
1972年 | 23篇 |
1971年 | 21篇 |
排序方式: 共有3450条查询结果,搜索用时 15 毫秒
11.
Event-related potentials (ERPs), accuracy scores, and reaction times were used to examine the recognition of emotional expressions. Adults and 7-year-old children saw upright and inverted chromatic slides of the facial expressions of happiness, fear, surprise, and anger, and were asked to press a button for either "happy" or "angry" faces. A positive-going waveform (P300) was apparent at parietal scalp (Pz) and at left and right temporal scalp. Although the behavioral data were similar for both children and adults (e.g., both had more difficulty recognizing angry expressions than happy ones, and angry expressions were more difficult to recognize upside-down than were happy faces), the ERPs indicated that children responded differently than adults did to happy and angry expressions. Adults showed greater P300 amplitude to happy faces, while children showed greater P300 amplitude to angry faces. In addition, for adults, but not children, there were greater P300 amplitude responses at right vs. left temporal scalp. 相似文献
12.
Judith M. Lavelle Melbourne F. Hovell M. Patricia West Dennis R. Wahlgren 《Journal of applied behavior analysis》1992,25(4):885-892
The Colorado Occupant Protection Project (COPP) intervention provided police with brief instruction concerning the importance of citations for drivers' failure to use child safety seats and special coupons to accompany citations. Coupons were exchangeable by drivers for a safety seat and brief training in its use, plus a waiver of the $50 citation fine. Over 4.5 years of archival records were employed, using an ABA design and a comparison community to evaluate the program. Few tickets were issued for nonuse of safety seats during the 3-year baseline in either community. Citations for nonuse of safety seats increased to over 50 per month during the intervention period at the test site, whereas rates remained essentially zero at the comparison site. After the COPP intervention was removed at the intervention site, citation rates for nonuse of safety seats decreased to about 15 per month. Differences between intervention conditions and settings were statistically significant. During the intervention, officers were 44 times more likely to write citations than were controls. Results suggested that a behavioral program can increase police citation writing for child protection purposes. 相似文献
13.
Elizabeth Marie McGhee Nelson 《Journal of psycholinguistic research》1992,21(2):111-125
The purpose of this study was to investigate memory for metaphors by nonfluent bilinguals under different orientation conditions. In Experiment 1 beginning bilinguals were asked to either (1) translate into English the figurative meanings of metaphors in the second language (L2); (2) translate into English the literal meanings of these same metaphorical sentences; (3) translate these metaphorical sentences into English-no specific instructions as how to translate given; (4) translate into English a similar list of nonmetaphorical sentences; (5) copy in L2 the list of metaphorical sentences; or (6) copy in L2 the list of nonmetaphorical sentences. Subjects' memory for these sentences was measured on a cued recall test. In Experiment 2 monolingual subjects did language tasks similar to conditions 1, 5, and 6 in Experiment 1. In both experiments, recall was best in the first condition and worst in the fifth condition. In Experiment 1 recall was also poorer in the second condition than in the other translation conditions. The implication is that the task for this condition requires subjects to process materials in a counterintuitive manner. 相似文献
14.
When a judgment task evokes unbiased estimates (i.e. the errors in individual judgments are distributed randomly around the true value), mathematical aggregation of individual estimates, even by a simple arithmetic mean, often will outperform all group members. However, when a task evokes biased estimates, mathematical aggregation does not perform so well. In this study, simulated data were accumulated to specify the expected' accuracy of mathematical aggregation relative to the accuracy of observed judgment of individual group members under varying conditions of task bias. Three types of judgment tasks were employed: (1) single-estimate, holistic tasks, (2) multiple-estimate, ranking tasks, and (3) multi-cue, decomposed tasks. Findings indicated across all task types that a large percentage of judgment-making group estimates formed strictly by computing the arithmetic mean of individual estimates performed better than their most capable members when a judgment task evoked little or no bias, a result particularly pronounced for ranking tasks. When the task was more greatly bias-evoking, a large percentage of parallel groups performed more poorly than average (or median) members, again a pattern more starkly evident for ranking tasks. These results suggest that the extent to which a judgment task evokes bias in a population of prospective group members is an important explanatory variable deserving much greater attention in the study of group performance. For example, an assertion about the efficacy of a particular group intervention based on a reliable demonstration of group performance as accurate as the most capable members may be unfounded when a task evokes no bias, since the baseline standard under such conditions should be much higher. By selecting tasks and populations that jointly produced highly biased estimates, researchers can lower the performance floor enough to detect (with reasonably small samples of groups) experimental effects should they occur. 相似文献
15.
James Lindemann Nelson 《Theoretical medicine and bioethics》1992,13(4):319-328
Mary Anne Warren's claim that there is room for only one person with full and equal rights inside a single human skin ([1], p. 63) calls attention to the vast range of moral conflict engendered by assigning full basic moral rights to fetuses. Thereby, it serves as a goad to thinking about conflicts between pregnant women and their fetuses in a way that emphasizes relationships rather than rights. I sketch out what a care orientation might suggest about resolving gestational conflicts. I also argue that the care orientation, with its commitment to the significance of the partial and the particular, cannot be absorbed within standard, impartialist moral theory. 相似文献
16.
The costs produced by invalid precues can depend on the spatial relationship between the cued location and the target location. If oculomotor programs mediate attention shifts, then the effect of varying the spatial relation between the cue and target should be the same for covert orienting (indexed by manual responses) and saccadic responses. We found this to be true only for central precues. With central precues, both manual and saccadic costs were greater when cue and target occurred on opposite sides of the vertical meridian than when they occurred on the same side. With peripheral precues, there were no meridian effects in either response condition, but there was a significant dissociation in the pattern of saccadic and manual costs. For manual responses costs were greater when the target was eccentric relative to the cue, whereas for saccades costs were greater when the cue was eccentric to the target. These results provide additional support for the idea that different orienting mechanisms are engaged by central and peripheral precues. They further suggest that the relationship between oculomotor and attentional orienting may depend on the nature of the precue, with the potential for interdependence being greater with central precues. 相似文献
17.
D A Nelson 《Journal of comparative psychology (Washington, D.C. : 1983)》1989,103(2):171-176
Estimate the amount of frequency variation that affected individual and species recognition by song in territorial male field sparrows with field playbacks of neighbors' songs lowered in frequency in 6 increments between 324 and 1296 Hz. Males gave strong responses to neighbors' songs that had been lowered by about 400 Hz, which is about 11% of the mean midfrequency in field sparrow song. Territorial responses were eliminated when neighbors' songs were lowered by more than about 900 Hz. Thus, there is a fairly narrow range of frequencies within which field sparrow songs can vary while functioning in communication. Ss' responses appear to be constrained by the normal range of song frequency variation within the species, but the range of variability within songs of individuals did not influence the degree of frequency shift required to render neighbors' songs unfamiliar. 相似文献
18.
19.
John M. Eiler Walter W. Nelson Craig C. Jensen Steven P. Johnson 《Behavior research methods》1989,21(1):53-58
Using bar code technology to automate data collection provides a rapid and reliable alternative to paper-and-pencil tracking or keyboard entry into pocket or laptop computer. An array of bar code symbols is printed on a data menu, with a unique symbol corresponding to each possible observation. Bar code symbols are scanned using hand-held readers, which record the event, log the observation time, and store data for transfer to a personal computer. Advantages of the bar code monitoring system include: (1) ease of use by staff with minimal technical training, (2) reduced data entry errors and increased entry speed, (3) reliable portable operation, and (4) low-cost hardware. While the bar code system described here is used for behavioral monitoring in a residential treatment setting for the developmentally disabled, with minimal modification this system can be adapted for use in a wide variety of research and clinical applications. 相似文献
20.
Patricia J. Krantz Steven E. Rams Land Lynn E. McClannahan 《Behavioral Interventions》1989,4(3):171-189
In this study, an autistic youth served as peer prompter for three other autistic adolescents. The peer prompter encouraged the other boys to talk about sports, a topic frequently discussed by typical teenagers. A multiple-baseline design across participants was used to assess the effectiveness of the peer-prompting procedure. During baseline, the youth rarely talked about sports, although all three had previously completed a sports-appreciation class and had displayed large pre-to-post gains on a paper-and-pencil test. During intervention, when a peer prompted sports discussions, all three youth engaged in much more sports-related conversation. Generalization measures indicated that: (1) the youth engaged in sports discussions in groups, as well as in the dyads that characterized the training situation; (2) they talked about sports in a setting other than the training setting; (3) they discussed sports with their peers when an unfamiliar teacher was present; and (4) they continued to discuss sports when training tapes and behavioral contracts between the teacher and the peer prompter were withdrawn. Previously, it has been common to use nonhandicapped or less-handicapped peers as tutors; this study demonstrates that an autistic youth may also effectively serve as a prompter who assists his schoolmates in acquiring conversational skills that contribute to their normalization. 相似文献