全文获取类型
收费全文 | 933篇 |
免费 | 61篇 |
国内免费 | 1篇 |
出版年
2024年 | 5篇 |
2023年 | 13篇 |
2022年 | 9篇 |
2021年 | 15篇 |
2020年 | 37篇 |
2019年 | 23篇 |
2018年 | 50篇 |
2017年 | 39篇 |
2016年 | 57篇 |
2015年 | 29篇 |
2014年 | 34篇 |
2013年 | 130篇 |
2012年 | 55篇 |
2011年 | 49篇 |
2010年 | 31篇 |
2009年 | 24篇 |
2008年 | 21篇 |
2007年 | 36篇 |
2006年 | 31篇 |
2005年 | 21篇 |
2004年 | 25篇 |
2003年 | 18篇 |
2002年 | 17篇 |
2001年 | 12篇 |
2000年 | 13篇 |
1999年 | 15篇 |
1998年 | 9篇 |
1997年 | 9篇 |
1994年 | 5篇 |
1993年 | 7篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 13篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 12篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1973年 | 9篇 |
1971年 | 4篇 |
1969年 | 5篇 |
1968年 | 6篇 |
1966年 | 5篇 |
排序方式: 共有995条查询结果,搜索用时 0 毫秒
171.
172.
Motion in depth results in radial optic-flow patterns. Forward motion results in radially expanding patterns, whereas backward motion generates contracting patterns. Radial optic-flow patterns are typically represented with a positive speed gradient, ie zero speed at the point of fixation, and maximum speed at the periphery. However, the actual speed profile in such a stimulus will depend upon the relative depth of objects in the scene. Using large-field stimuli (82 deg diameter) we determined relative sensitivities to radial expansion and contraction patterns and also to various types of speed gradients: positive, negative, random, and flat. We found that, even when large-field stimuli are used, observers are more sensitive to radially contracting patterns than to expanding patterns. Sensitivity to the positive speed gradient was not consistently different from either the negative or random gradients. Sensitivity to the flat gradient depended upon the speed of the stimuli. The finding of greater sensitivity to radial contraction is discussed in terms of the functional requirements involved in the use of optic-flow signals in maintaining balance. On the basis of the present findings, the utility of comparing psychophysical results based on thresholds against physiological data based on suprathreshold stimuli is also discussed. 相似文献
173.
Suicide deaths are often viewed as sudden and unexpected. Research examining bereavement responses to suicide are generally set within this conceptual framework. Twenty-two parents were interviewed about their bereavement experience following the suicide death of a young adult son or daughter. Data analyzed using narrative methods revealed the concept of preparedness. Three distinct preparedness narratives were identified, termed turbulent-relief, tragedy, and reflective plots. The data presented here highlights the way in which these different situations influence the resultant grief. Understanding preparedness for suicide assists in explaining the variety of grief responses in parents bereaved in this manner. 相似文献
174.
The children's gambling task (CGT [Kerr, A., & Zelazo, P. D. (2004). Development of “Hot” executive function: The children's gambling task. Brain and Cognition, 55, 148–157]) involves integrating information about losses and gains to maximize winnings when selecting cards from two decks. Both cognitive complexity and control (CCC) theory and relational complexity (RC) theory attribute younger children's difficulty to task complexity. In CCC theory, identification of the advantageous deck requires formulation of a higher-order rule so that gains and losses can be considered in contradistinction. According to RC theory, it entails processing the ternary relation linking three variables (deck, magnitude of gain, magnitude of loss). We designed two less complex binary-relational versions in which either loss or gain varied across decks, with the other held constant. The three closely matched versions were administered to 3–5-year-olds. Consistent with complexity explanations, children in all age groups selected cards from the advantageous deck in the binary-relational versions, but only 5-year-olds did so on the ternary-relational CGT. 相似文献
175.
The neural consequences of semantic richness: when more comes to mind, less activation is observed 总被引:1,自引:0,他引:1
Some concepts have richer semantic representations than others. That is, when considering the meaning of concepts, subjects generate more information (more features, more associates) for some concepts than for others. This variability in semantic richness influences responses in speeded tasks that involve semantic processing, such as lexical decision and semantic categorization tasks. It has been suggested that concepts with richer semantic representations build stronger attractors in semantic space, allowing faster settling of activation patterns and thus faster responding. Using event-related functional magnetic resonance imaging, we examined the neural activation associated with semantic richness by contrasting activation for words with high and low numbers of associates in a semantic categorization task. Results were consistent with faster semantic settling for words with richer representations: Words with a low number of semantic associates produced more activation than words with a high number of semantic associates in a number of regions, including left inferior frontal and inferior temporal gyri. 相似文献
176.
Nonnormality and divergence in posttreatment alcohol use: reexamining the Project MATCH data "another way." 总被引:1,自引:0,他引:1
Witkiewitz K van der Maas HL Hufford MR Marlatt GA 《Journal of abnormal psychology》2007,116(2):378-394
Alcohol lapses are the modal outcome following treatment for alcohol use disorders, yet many alcohol researchers have encountered limited success in the prediction and prevention of relapse. One hypothesis is that lapses are unpredictable, but another possibility is the complexity of the relapse process is not captured by traditional statistical methods. Data from Project Matching Alcohol Treatments to Client Heterogeneity (Project MATCH), a multisite alcohol treatment study, were reanalyzed with 2 statistical methodologies: catastrophe and 2-part growth mixture modeling. Drawing on previous investigations of self-efficacy as a dynamic predictor of relapse, the current study revisits the self-efficacy matching hypothesis, which was not statistically supported in Project MATCH. Results from both the catastrophe and growth mixture analyses demonstrated a dynamic relationship between self-efficacy and drinking outcomes. The growth mixture analyses provided evidence in support of the original matching hypothesis: Individuals with lower self-efficacy who received cognitive behavior therapy drank far less frequently than did those with low self-efficacy who received motivational therapy. These results highlight the dynamical nature of the relapse process and the importance of the use of methodologies that accommodate this complexity when evaluating treatment outcomes. 相似文献
177.
Enriching the environment of alphaCaMKIIT286A mutant mice reveals that LTD occurs in memory processing but must be subsequently reversed by LTP
下载免费PDF全文
![点击此处可从《Learning & memory (Cold Spring Harbor, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Parsley SL Pilgram SM Soto F Giese KP Edwards FA 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(1-2):75-83
alphaCaMKII(T286A) mutant mice lack long-term potentiation (LTP) in the hippocampal CA1 region and are impaired in spatial learning. In situ hybridization confirms that the mutant mice show the same developmental expression of alphaCaMKII as their wild-type littermates. A simple hypothesis would suggest that if LTP is a substrate for learning, then enriching the environment should cause learning-dependent changes in wild-type mice that have LTP. Such changes would not be seen in LTP-deficient alphaCaMKII(T286A) mutants. Excitatory synaptic currents in CA1 neurons, recorded with patch clamp in brain slices, revealed that enrichment induces an increase in glutamate release probability and a decreased miniature current amplitude. Confocal microscopy also showed dendritic spine density to be reduced. However, contrary to the hypothesis above, these enrichment-induced changes occur only in the mutant mice and are not detectable in wild-type littermates. We suggest that enrichment induces alphaCaMKII-independent changes in both wild-type and mutant mice. Such changes may be subsequently reversed in wild-type animals via alphaCaMKII-dependent mechanisms, such as LTP. Reversal of plasticity has long been hypothesized to be essential for the hippocampus to maintain its role in memory processing. The inability to reverse plasticity in alphaCaMKII(T286A) mutant mice would then result in impairment of spatial learning. 相似文献
178.
Predicting having a best friend in young children: individual characteristics and friendship features 总被引:1,自引:0,他引:1
In this study, the authors investigated the characteristics that predict best friend status in young children. One hundred and twenty-four preschool, kindergarten, and first-grade children identified their "best friend" and up to four "other friends" in their class. Teachers completed a questionnaire about each friendship to determine positive and negative features of the relationships. First, the authors used individual characteristics to predict if a child had a best friend. The variables age, gender, and peer acceptance predicted that a child would have a best friend. Second, positive friendship features positively predicted best friendships in analyses of all friendship pairs. Best friendships are meaningful relationships to children even at this young age and offer children more positive experiences than do other friendships. 相似文献
179.
Meier BP Hauser DJ Robinson MD Friesen CK Schjeldahl K 《Journal of personality and social psychology》2007,93(5):699-710
"God" and "Devil" are abstract concepts often linked to vertical metaphors (e.g., "glory to God in the highest," "the Devil lives down in hell"). It is unknown, however, whether these metaphors simply aid communication or implicate a deeper mode of concept representation. In 6 experiments, the authors examined the extent to which the vertical dimension is used in noncommunication contexts involving God and the Devil. Experiment 1 established that people have implicit associations between God-Devil and up-down. Experiment 2 revealed that people encode God-related concepts faster if presented in a high (vs. low) vertical position. Experiment 3 found that people's memory for the vertical location of God- and Devil-like images showed a metaphor-consistent bias (up for God; down for Devil). Experiments 4, 5a, and 5b revealed that people rated strangers as more likely to believe in God when their images appeared in a high versus low vertical position, and this effect was independent of inferences related to power and likability. These robust results reveal that vertical perceptions are invoked when people access divinity-related cognitions. 相似文献
180.
The literature on pain and aggression has indicated that pain elicits aggression. However, research has generally examined pain as a situational variable and focused less on the dispositional ability of an individual to tolerate pain. The dearth of research on pain tolerance and aggression appears to contradict the existing theory on the aggression‐eliciting effect of pain, in that studies have found a positive relationship between pain tolerance and aggression. The purpose of this study was to determine whether the relationship between pain tolerance and aggression is moderated by sex and whether the positive relationship could be explained by masculine gender role conformity. A sample of 195 collegiate men and women completed trait measures and a laboratory assessment of pain tolerance. Results indicated that correlations between pain tolerance and trait aggression were significant and positive for men but not women. However, when men's conformity to masculine gender role was controlled for, the relationship between pain tolerance and trait aggression was nil and nonsignificant. Results are discussed in reference to socialization and maintenance of masculine status. Aggr. Behav. 35:422–429, 2009. © 2009 Wiley‐Liss, Inc. 相似文献