全文获取类型
收费全文 | 10022篇 |
免费 | 473篇 |
国内免费 | 12篇 |
专业分类
10507篇 |
出版年
2023年 | 76篇 |
2022年 | 63篇 |
2021年 | 124篇 |
2020年 | 214篇 |
2019年 | 202篇 |
2018年 | 291篇 |
2017年 | 280篇 |
2016年 | 338篇 |
2015年 | 223篇 |
2014年 | 284篇 |
2013年 | 1015篇 |
2012年 | 473篇 |
2011年 | 505篇 |
2010年 | 325篇 |
2009年 | 301篇 |
2008年 | 415篇 |
2007年 | 440篇 |
2006年 | 367篇 |
2005年 | 367篇 |
2004年 | 342篇 |
2003年 | 321篇 |
2002年 | 329篇 |
2001年 | 188篇 |
2000年 | 118篇 |
1999年 | 154篇 |
1998年 | 132篇 |
1997年 | 129篇 |
1996年 | 110篇 |
1995年 | 111篇 |
1994年 | 109篇 |
1993年 | 101篇 |
1992年 | 121篇 |
1991年 | 104篇 |
1990年 | 90篇 |
1989年 | 73篇 |
1988年 | 71篇 |
1987年 | 77篇 |
1986年 | 80篇 |
1985年 | 96篇 |
1984年 | 84篇 |
1983年 | 88篇 |
1982年 | 80篇 |
1981年 | 87篇 |
1980年 | 82篇 |
1979年 | 81篇 |
1978年 | 97篇 |
1977年 | 89篇 |
1976年 | 76篇 |
1975年 | 66篇 |
1974年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
When procedural artifacts are controlled, it has been difficult to demonstrate directed forgetting in pigeons. However, previous research with pigeons has not allowed for the reallocation of working memory (from forget items to remember items) on forget-cued trials as is possible in human directed forgetting experiments. In the present experiment, directed forgetting was found while controlling for procedural artifacts and allowing the pigeons to reallocate memory resources on forget trials. The results indicate that under these conditions, pigeons have active control over memory processing. 相似文献
132.
A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear. 相似文献
133.
Silvia A. Bunge Juliane Mauelshagen Thomas J. Carew 《Neurobiology of learning and memory》1997,67(3):259-263
Tail shock induces reflex sensitization inAplysiaand, in parallel, induces a number of modulatory effects in central neurons, such as increased excitability in tail sensory neurons (SNs) and facilitation of synaptic transmission from SNs to motor neurons. Both of these modulatory effects are mimicked by exogenous application of serotonin (5HT) or electrical stimulation of the tail nerve P9. In the present study we examined the activation thresholds for increased excitability and synaptic facilitation induced by either 5HT or P9 stimulation. We found that the concentration of 5HT sufficient to produce a significant increase in excitability produced no significant synaptic facilitation and, conversely, that the intensity of nerve stimulation sufficient to produce significant synaptic facilitation produced no excitability changes. This reversal of relative thresholds for these modulatory effects may reflect the differential access of exogenous 5HT and endogenous 5HT (released by tail nerve stimulation) to the SN cell body and synaptic terminals, respectively. 相似文献
134.
Lorraine G. Allan Shepard Siegel Chandani Kulatunga-Moruzi Thomas Eissenberg C. Andrew Chapman 《Attention, perception & psychophysics》1997,59(8):1327-1334
In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These experiments expand on previous research concerned with the role of luminance contrast in the induction of orientation-CCAEs by eliminating alternative explanations. 相似文献
135.
Mark A. Barnett Guy D. Vitaglione Kimberly K. G. Harper Steven W. Quackenbush Lee Ann Steadman Birgit S. Valdez 《Journal of applied social psychology》1997,27(15):1316-1334
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames. 相似文献
136.
This study of a sample of working women investigated where positive experiences were derived from in everyday life, focusing on the domains of work and nonwork (leisure). It examined how aspects of the situation, in terms of principal environmental influences in work and leisure, and the person, in terms of locus of control, were associated with positive subjective states and psychological well-being. The study employed questionnaires and also the experience sampling method. The results showed that both work and leisure were important for positive psychological states and that internal locus of control was associated with greater enjoyment, interest, feelings of immediate control, intrinsic motivation, life satisfaction, and affective well-being and a number of principal environmental influences. 相似文献
137.
Emmanuel Onifade Paul D. Harrison Thomas P. Cafferty 《Journal of applied social psychology》1997,27(5):439-452
This study examined the escalation problem within an attribution theory framework. Students read a case scenario containing causal attribution information that described a poorly performing project under their supervision. They made estimates of its future success, as well as a decision whether to continue it. Perceived stability of causality had the primary effect on expectancy of success. A project whose performance downturn was attributed to a stable cause had a lower expectancy. Locus of causality had a smaller but still significant effect. Project downturns attributed to internal causes had a lower expectancy. Expectancy of success was significantly correlated with project continuation decisions. Discrepancies between these results and those reported by Staw and Ross (1978) are accounted for in terms of Weiner's (1985, 1986) attributional analysis. 相似文献
138.
Thomas Holtgraves 《Memory & cognition》1997,25(1):106-116
Three experiments were conducted to examine whether people spontaneously remember the wording used to convey politeness. In all experiments, subjects heard statements varying in politeness that had been made by either a high-status (e.g., a professor) or equal-status (e.g., another student) speaker. Subjects’ incidental memory for these statements was then tested with either a recognition (Experiments 1 and 3) or a recall (Experiment 2) procedure. As expected, there was evidence of significant memory for wording that conveyed politeness, and subjects were more likely to remember forms that were incongruous with the speaker’s status. There was also some evidence that subjects encoded the politeness of a remark even when they were unable to recall the specific remark. The results demonstrate the role of the interpersonal dimension in the processing of language in context. 相似文献
139.
The philosophy of chemistry has been sadly neglected by most contempory literature in the philosophy of science. This paper argues that this neglect has been unfortunate and that there is much to be learned from paying greater philosophical attention to the set of issues defined by the philosophy of chemistry. The potential contribution of this field to such current topics as reduction, laws, explanation, and supervenience is explored, as are possible applications of insights gained by such study to the philosophy of mind and the philosophy of social science. 相似文献
140.
Thomas Wasow 《Journal of psycholinguistic research》1997,26(3):347-361
Explanations of the tendency to put long, complex constituents at the ends of sentences (end-weight) usually take the listener's perspective, claiming it facilitates parsing. I argue for a speaker-oriented explanation of end-weight, based on how it facilitates utterance planning. Parsing is facilitated when as much tree structure as possible can be determined early in the string, but production is easiest when options for how to continue are kept open. That is, listeners should prefer early commitment and speakers should prefer late commitment. Corpus data show that different verbs exhibit different rates of word-order variation that are systematically related to differences in subcategorization possibilities in just the way predicted by a strategy of late commitment. Thus, a speaker-based account of lexical preferences in word ordering does a better job of explaining variation in weight effects than a listener-based account. 相似文献