全文获取类型
收费全文 | 5702篇 |
免费 | 254篇 |
出版年
2023年 | 42篇 |
2022年 | 31篇 |
2021年 | 47篇 |
2020年 | 110篇 |
2019年 | 111篇 |
2018年 | 151篇 |
2017年 | 151篇 |
2016年 | 204篇 |
2015年 | 143篇 |
2014年 | 122篇 |
2013年 | 620篇 |
2012年 | 258篇 |
2011年 | 321篇 |
2010年 | 192篇 |
2009年 | 220篇 |
2008年 | 248篇 |
2007年 | 286篇 |
2006年 | 224篇 |
2005年 | 218篇 |
2004年 | 231篇 |
2003年 | 235篇 |
2002年 | 205篇 |
2001年 | 120篇 |
2000年 | 105篇 |
1999年 | 105篇 |
1998年 | 105篇 |
1997年 | 79篇 |
1996年 | 83篇 |
1995年 | 78篇 |
1994年 | 87篇 |
1993年 | 57篇 |
1992年 | 76篇 |
1991年 | 43篇 |
1990年 | 51篇 |
1989年 | 34篇 |
1988年 | 23篇 |
1987年 | 38篇 |
1986年 | 35篇 |
1985年 | 39篇 |
1984年 | 33篇 |
1983年 | 53篇 |
1982年 | 42篇 |
1981年 | 32篇 |
1980年 | 29篇 |
1979年 | 40篇 |
1978年 | 45篇 |
1977年 | 30篇 |
1976年 | 30篇 |
1974年 | 13篇 |
1973年 | 13篇 |
排序方式: 共有5956条查询结果,搜索用时 15 毫秒
241.
McLeod P Reed N Dienes Z 《Journal of experimental psychology. Human perception and performance》2002,28(6):1499-1501
According to linear optic trajectory (LOT) theory, fielders use the direction of curvature of theoptic trajectory to control the way they run to intercept the ball. Data presented by D. M. Shaffer and M. K. McBeath (2002) as support for LOT theory show that the optic trajectory of balls that will fall behind the fielder provide the cue that LOT theory predicts would send the fielder running forward, not backward. In this article, the authors show that watching these balls would provide the fielder with the cue that the optic acceleration cancellation (OAC) theory of interception predicts would send the fielder running backward. It appears that the fielders studied by Shaffer and McBeath were following the cue predicted by OAC theory, not that predicted by LOT theory. 相似文献
242.
In a series of experiments, we examined the effect of perceptual objects on visual attentional processing in the presence of spatially cued attentional selection. Subjects made speeded judgments about two visual elements that were either both on the same object or on two different objects. Judgments were faster when the elements were on the same object than when they were on different objects, revealing an object advantage. Importantly, the object advantage remained even when either exogenous or endogenous spatial cues were used to direct the subjects' attention to a part of the display, contrary to earlier findings of other researchers. The object advantage, however, did disappear when the stimulus duration was shortened substantially. The results show that object-based selection is pervasive and is not diminished by the act of selective attention. The results are discussed in terms of their implications for the mechanisms that underlie attentional selection. 相似文献
243.
The authors argue against a purely behavioral definition of praise as verbal reinforcement in favor of the view that praise may serve to undermine, enhance, or have no effect on children's intrinsic motivation, depending on a set of conceptual variables. Provided that praise is perceived as sincere, it is particularly beneficial to motivation when it encourages performance attributions to controllable causes, promotes autonomy, enhances competence without an overreliance on social comparisons, and conveys attainable standards and expectations. The motivational consequences of praise also can be moderated by characteristics of the recipient, such as age, gender, and culture. Methodological considerations, such as including appropriate control groups and measuring postfailure outcomes, are stressed, and directions for future research are highlighted. 相似文献
244.
This study, using secondary data analysis, examined prospectively a mediation model of the relationship between acculturation and problem behavior proneness among 330 Hispanic children and adolescents from an urban school district in the southwest region of the United States. Acculturation was predicted to have an indirect, but positive, relationship to problem behavior proneness through parental involvement and self-esteem. The results partially supported the model and indicated that parental involvement, but not self-esteem, played a significant mediational role in children's problem behavior proneness. The individual indicators of problem behavior proneness among Hispanic youth were significantly interrelated, which is consistent with problem behavior theory as conceptualized by R. Jessor (1984) and R. Jessor and S. L. Jessor (1977). Findings from this study provide implications for future research and intervention designs. 相似文献
245.
Previous studies have found that priming a target like cerr-o ("hill") with an unmasked stem-homograph (e.g., cerr-ar, "to close") or with an unmasked allomorph of a stem-homograph (e.g., cierr-a, "he/she/it closes") has an inhibitory effect on target recognition. We report evidence from stem-homograph priming studies that implicate both morphological parsing and lexical selection processes at the lemma level. We argue that stem-homograph inhibition is the product of lexical selection mechanisms that are engaged just when a fully ambiguous stimulus (here, an inflectional stem) must be assigned one of its viable interpretations in order to afford conscious perception of lexical identity. 相似文献
246.
The primary purpose of the study was to identify event-based prospective-memory tasks that provide sensitive and reliable tools for assessing effects of normal aging in prospective-memory performance. Four prospective-memory tasks were selected from the literature or were newly developed, with the tasks differing on various dimensions that, for theoretical reasons or based on previous evidence, might determine task sensitivity to age effects on prospective-memory performance: perceptual saliency of prospective target events, frequency of occurrence of prospective target events, complexity of prospective-memory instructions, and provision of feedback after prospective-memory errors. Two of the four tasks yielded large and robust age effects on prospective-memory performance. Correlational analyses suggested that these age effects on prospective-memory performance were mediated, at least in part, by a reduced ability of older adults to maintain prospective intentions in a highly activated state and not by age effects on basic mental speed alone. 相似文献
247.
Simon TR Anderso M Thompson MP Crosby A Sacks JJ 《Suicide & life-threatening behavior》2002,32(1):42-50
Data from a nationally representative sample of 5,238 U.S. adults were used to examine the extent to which physical assault victimization was associated with suicidal ideation or behavior (SIB). The results from multivariable logistic regression analyses indicate that physical assault victimization was positively associated with SIB after adjusting for sociodemographic characteristics and alcohol use (OR = 3.6; 95% CI = 2.4-5.5). Those who were injured during the most recent physical assault (OR = 2.7; 95% CI = 1.2-6.0) and those who were assaulted by a relative (OR = 3.4; 95% CI= 1.0-11.0) or intimate partner (OR = 7.7; 95% CI = 2.7-22.5) were significantly more like to report SIB than victims who were not injured or were assaulted by a stranger. Also, those who were victimized but not injured (OR = 5.6; 95% CI = 3.8-8.2) and those who were victimized by a stranger (OR = 2.9; 95% CI = 1.4-6.0) were more likely to report SIB than non-victims. These results highlight the need for legal, medical, mental health, and social service providers to address the co-occurrence of violent victimization and suicidal ideation, particularly, but not exclusively, victimization by family members and intimates. 相似文献
248.
Sokoloff G Blumberg MS 《Journal of comparative psychology (Washington, D.C. : 1983)》2002,116(3):240-246
Infant Syrian golden hamsters (Mesocricetus auratus) do not exhibit endogenous heat production before 3 weeks of age and do not huddle effectively during cold exposure, gaining little thermoregulatory benefit from the presence of multiple littermates. In contrast, infant Norway rats (Rattus norvegicus) produce heat endogenously and are effective at maintaining elevated body temperatures by huddling. Therefore, the ineffective huddling of infant hamsters may be due to the absence of endogenous heat production. The huddling behavior of infants in mixed huddles of 8-day-old hamsters and weight-matched 4-5-day-old rats was observed to explore this possibility. The results indicate that hamsters, even when cold, effectively gain access to heat-producing rats, supporting the idea that endothermy contributes to the behavior of huddling by providing heat to each individual and thermal stimuli to other infants to support aggregation. 相似文献
249.
250.
This paper reviews the literature on performance on standard neuropsychological tests among individuals with posttraumatic stress disorder (PTSD). Of 19 studies, 16 reported impairment of attention or immediate memory (or both); however, most of these studies included PTSD patients with significant psychiatric comorbidity, so that the extent to which the observed deficits are specifically attributable to PTSD remains unclear. Other potential confounds, including medical illness, substance abuse, and motivational factors, further preclude definitive conclusions at present. Results of structural and functional neuroimaging studies of PTSD are also summarized. Two studies have reported correlations between hippocampal volume and cognitive findings in PTSD patients; functional studies have indicated specific findings in limbic regions, although the relationship of these results to neuropsychological performance remains to be explored. 相似文献