全文获取类型
收费全文 | 2528篇 |
免费 | 157篇 |
国内免费 | 1篇 |
出版年
2024年 | 5篇 |
2023年 | 34篇 |
2022年 | 51篇 |
2021年 | 47篇 |
2020年 | 66篇 |
2019年 | 103篇 |
2018年 | 114篇 |
2017年 | 121篇 |
2016年 | 140篇 |
2015年 | 86篇 |
2014年 | 102篇 |
2013年 | 311篇 |
2012年 | 179篇 |
2011年 | 162篇 |
2010年 | 104篇 |
2009年 | 95篇 |
2008年 | 111篇 |
2007年 | 118篇 |
2006年 | 104篇 |
2005年 | 89篇 |
2004年 | 101篇 |
2003年 | 69篇 |
2002年 | 66篇 |
2001年 | 25篇 |
2000年 | 30篇 |
1999年 | 24篇 |
1998年 | 26篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 20篇 |
1994年 | 10篇 |
1993年 | 14篇 |
1992年 | 19篇 |
1991年 | 10篇 |
1990年 | 11篇 |
1989年 | 6篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 3篇 |
1973年 | 3篇 |
排序方式: 共有2686条查询结果,搜索用时 15 毫秒
271.
272.
Linda B. Hassing Brent J. Small Eva von Strauss Laura Fratiglioni Lars Bäckman 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(1):11-20
We examined cross-sectional differences and longitudinal changes in episodic memory performance related to impending death among a group of very old people, aged 90–101 years. Participants were assessed at 3 measurement points across a 6-year interval. Three groups were identified: those who survived the entire follow-up period (n =40), those who died before the first follow-up (n =44), and those who died after the first follow-up (n =14). Participants completed a battery of episodic memory tasks consisting of face recognition, word recognition, word recall, and object recall with selective reminding. Those who survived performed better than those who were going to die in object recall at baseline. A Cox regression analysis, controlling age, revealed that object recall performance was significantly related to subsequent mortality status. Longitudinal analyses demonstrated significant 3-year decline for both face recognition and object recall, but no evidence of differential decline as a function of mortality group. Thus, longitudinal changes in memory preceding death were not as pronounced as the corresponding cross-sectional differences in this very old sample. In general, the results suggest that mortality-related memory deficits are present in extreme old age, although these deficits are relatively small and task-specific. 相似文献
273.
274.
Laura Capitaine Katrien Devolder Guido Pennings 《Theoretical medicine and bioethics》2013,34(3):207-226
Recent developments in biogerontology—the study of the biology of ageing—suggest that it may eventually be possible to intervene in the human ageing process. This, in turn, offers the prospect of significantly postponing the onset of age-related diseases. The biogerontological project, however, has met with strong resistance, especially by deontologists. They consider the act of intervening in the ageing process impermissible on the grounds that it would (most probably) bring about an extended maximum lifespan—a state of affairs that they deem intrinsically bad. In a bid to convince their deontological opponents of the permissibility of this act, proponents of biogerontology invoke an argument which is grounded in the doctrine of double effect. Surprisingly, their argument, which we refer to as the ‘double effect argument’, has gone unnoticed. This article exposes and critically evaluates this ‘double effect argument’. To this end, we first review a series of excerpts from the ethical debate on biogerontology in order to substantiate the presence of double effect reasoning. Next, we attempt to determine the role that the ‘double effect argument’ is meant to fulfil within this debate. Finally, we assess whether the act of intervening in ageing actually can be justified using double effect reasoning. 相似文献
275.
Benito Arias Miguel Ángel Verdugo Patricia Navas Laura E. Gómez 《International Journal of Clinical and Health Psychology》2013,13(2):155-166
Although the presence of significant limitations in adaptive behavior constitutes one of the three necessary criteria for diagnosing intellectual disability, adaptive behavior structure has always been the subject of considerable controversy among researchers. The main goal of this study is to extend previous research results that provide further support to a multidimensional structure of conceptual, social, and practical skills compared to the unidimensional structure. One-factor and 3-correlated factors models as measured by 15 observable indicators were analyzed by means of confirmatory factor analysis (CFA), as well as their relationships with one second-order factor (i.e., adaptive behavior). To that end, 388 children with and without intellectual disabilities were assessed with the Diagnostic Adaptive Behavior Scale (DABS). Results of CFA indicated that the 3 first-order factors solution provides the best fit to the data. Reliability and validity of the multidimensional model were also analyzed through different methods such as the composite reliability and the average variance extracted. Finally, implications of these findings and possible directions for future research are discussed. 相似文献
276.
Laura E. Maphis Denise M. Martz Shawn S. Bergman Lisa A. Curtin Rose Mary Webb 《Body image》2013,10(3):361-368
Sixty-eight percent of U.S. adults are overweight/obese, and this epidemic has physical, psychosocial, and behavioral consequences. An internet sample of adults (N = 2997) perceiving themselves as larger than ideal in clothing size reported their body mass index (BMI), relative clothing size (RS; discrepancy between current and ideal size), and avoidance behaviors. Exploratory factor analysis of 10 avoidance items produced social avoidance and body display avoidance factors. A relative importance analysis revealed RS as a better predictor than BMI for avoidance. A hierarchical multivariate analysis of covariance found RS to predict both avoidance constructs. The relationship between RS and both avoidance constructs was stronger for women than men, and for younger as compared to older participants. Caucasians reported more body display avoidance than African Americans. This suggests that personal dissatisfaction with body size may deter involvement in varied life events and that women are especially avoidant of activities that entail displaying their bodies. 相似文献
277.
In this paper, we use mixed methods to develop a taxonomy of poverty and vulnerability to study the situation of children and their households in rural Ethiopia over time. The taxonomy is built using qualitative data from Young Lives, a long-term study of childhood poverty, with the specific purpose of analysing the context of children’s life trajectories using both quantitative and qualitative data. The approach aims to yield insights into changes over time as well as to reflect multiple dimensions and consider issues of current well-being and future ‘well-becoming’. It potentially allows for the identification of underlying mechanisms that influence and determine life trajectories. Until recently, quantitative and qualitative approaches towards the analysis of chronic and transient poverty have developed in isolation with little cross-disciplinary interaction. In this paper, we add to this body of research by using a mixed-method approach to develop a hybrid taxonomy of child poverty and well-being that can be used for a dynamic analysis. The paper also complements existing research and evidence on child poverty and well-being in the context of Ethiopia. 相似文献
278.
Decades of research on the concreteness effect, namely better memory for concrete as compared with abstract words, suggest it is a fairly robust phenomenon. Nevertheless, little attention has been given to limiting retrieval contexts. Two experiments evaluated intentional memory for concrete and abstract word lists in three retrieval contexts: free recall, explicit word-stem completion, and implicit word-stem completion. Concreteness effects were observed in free recall and in explicit word-stem completion, but not in implicit word-stem completion. These findings are consistent with both a bidirectional version of the relational-distinctiveness processing framework (Ruiz-Vargas, Cuevas, & Marschark, 1996) and a second framework combining insights from dual coding theory (Paivio, 1971, 1986) and the transfer appropriate processing framework (Roediger, Weldon, & Challis, 1989). Also, consistent with the relational-distinctiveness framework, the second experiment suggested that concreteness effects might depend on relational processing at encoding: Concreteness effects were observed in explicit memory for related word lists but not for unrelated word lists. 相似文献
279.
Drew Walker Laura Mickes Daniel Bajic Charles R. Nailon Timothy C. Rickard 《Journal of applied research in memory and cognition》2013,2(1):25-32
Children are exposed to multiple training tasks that are intended to support acquisition of basic arithmetic skills. Surprisingly, there is a scarcity of experimental research that directly compares the efficacy of those tasks, raising the possibility that children may be spending critical instructional time on tasks that are not effective. We conducted an experiment with 1st through 6th grade children comparing two arithmetic training tasks that are widely used: answer production training and fact triangle training. Results show that answer production training produces substantial fluency gains, whereas fact triangle training does not. Further, we show that, despite theoretical considerations that suggest otherwise, fact triangle training does not produce more flexibly applicable learning. Implications for memory representation, arithmetic fluency training, and broader educational strategy are discussed. 相似文献
280.