全文获取类型
收费全文 | 4010篇 |
免费 | 201篇 |
国内免费 | 1篇 |
专业分类
4212篇 |
出版年
2022年 | 24篇 |
2021年 | 43篇 |
2020年 | 73篇 |
2019年 | 97篇 |
2018年 | 114篇 |
2017年 | 129篇 |
2016年 | 140篇 |
2015年 | 89篇 |
2014年 | 98篇 |
2013年 | 446篇 |
2012年 | 182篇 |
2011年 | 185篇 |
2010年 | 114篇 |
2009年 | 105篇 |
2008年 | 165篇 |
2007年 | 153篇 |
2006年 | 151篇 |
2005年 | 152篇 |
2004年 | 138篇 |
2003年 | 107篇 |
2002年 | 120篇 |
2001年 | 74篇 |
2000年 | 70篇 |
1999年 | 77篇 |
1998年 | 58篇 |
1997年 | 62篇 |
1996年 | 55篇 |
1995年 | 41篇 |
1994年 | 36篇 |
1993年 | 37篇 |
1992年 | 53篇 |
1991年 | 37篇 |
1990年 | 29篇 |
1989年 | 35篇 |
1988年 | 30篇 |
1987年 | 37篇 |
1986年 | 28篇 |
1985年 | 49篇 |
1984年 | 45篇 |
1983年 | 42篇 |
1982年 | 43篇 |
1981年 | 48篇 |
1980年 | 28篇 |
1979年 | 30篇 |
1978年 | 34篇 |
1976年 | 31篇 |
1975年 | 26篇 |
1974年 | 24篇 |
1973年 | 30篇 |
1971年 | 28篇 |
排序方式: 共有4212条查询结果,搜索用时 0 毫秒
991.
Finch WH Chang M Davis AS Holden JE Rothlisberg BA McIntosh DE 《Behavior research methods》2011,43(4):942-952
Statistical prediction of an outcome variable using multiple independent variables is a common practice in the social and
behavioral sciences. For example, neuropsychologists are sometimes called upon to provide predictions of preinjury cognitive
functioning for individuals who have suffered a traumatic brain injury. Typically, these predictions are made using standard
multiple linear regression models with several demographic variables (e.g., gender, ethnicity, education level) as predictors.
Prior research has shown conflicting evidence regarding the ability of such models to provide accurate predictions of outcome
variables such as full-scale intelligence (FSIQ) test scores. The present study had two goals: (1) to demonstrate the utility
of a set of alternative prediction methods that have been applied extensively in the natural sciences and business but have
not been frequently explored in the social sciences and (2) to develop models that can be used to predict premorbid cognitive
functioning in preschool children. Predictions of Stanford–Binet 5 FSIQ scores for preschool-aged children is used to compare
the performance of a multiple regression model with several of these alternative methods. Results demonstrate that classification
and regression treesprovided more accurate predictions of FSIQ scores than does the more traditional regression approach.
Implications of these results are discussed. 相似文献
992.
Research suggests that exposure to sociocultural norms for idealized appearance can reduce both women's and men's body satisfaction. Despite comparable effects for both genders in the lab, in the “real-world” women's body satisfaction is chronically lower than men's. Real-world gender differences may arise from discrepancies in men's and women's everyday exposure to norms. Across eight studies using a variety of content analysis, survey, and experimental methods, we examine differences in sociocultural norms for ideal appearance pertaining to women and men in “daily life” contexts. We demonstrate that appearance norms encountered by women in daily life are more rigid, homogenous and pervasive than those for men, and that more messages implying the attainability of the ideal appearance are directed at women. Finally, experimental results show that homogeneous, rigid norms (like those typically encountered by women) are more harmful to body image than heterogeneous, flexible norms (like those typically encountered by men). 相似文献
993.
The diversity of nanotechnologies and of the governance challenges that their applications raise calls for exploration and
learning across different cases. We present an Upstream Oversight Assessment (UOA) of expected benefits and potential harms
of nanoparticles made of a synthetic polymer (PLGA) to improve vaccines for farmed salmon. Suggested by Jennifer Kuzma and
colleagues, an UOA may help identify and prioritise research needs, and it may support evaluations of the adequacy of relevant
existing regulatory frameworks. In this work, the UOA approach is modified and supported with elements from the uncertainty
analysis framework developed by Warren Walker and colleagues. Empirically, we draw on relevant available published literature
and insights generated in an ongoing nanoparticle salmon vaccine project, in which one of the authors participates. Nanotechnologies
have not previously been encountered in the regulatory context of fish vaccines, which in part raises unique challenges due
to prospective large scale vaccine use in semi-open aquatic systems. Strengthened through cooperation between ELSA and technology
researchers we found the UOA useful for an early mapping of benefits and concerns, and for identifying areas in need of further
research prior to a nanoparticle based salmon vaccine is developed and taken into use. We consider our approach to represent
one among several complementing initiatives that seek to contribute to early stage evaluations of possible negative side effects,
broadly conceived, in order to facilitate a more robust nanotechnology development. 相似文献
994.
G. Scott Davis 《The Journal of religious ethics》2019,47(2):417-424
This response suggests that in writing the history of ethics, it is important to take seriously what the principals wrote and believed, distinguishing it carefully from our own responses to their writings, or from subsequent uses to which their writings may have been put. For example, when reading Thomas Aquinas and Francisco de Vitoria on just war against non‐Christian peoples, forcible conversion and conquest are clearly condemned. Whatever the attitudes of their contemporaries, not to mention later thinkers up to the present, there is no foundation in Aquinas and Vitoria for holy war or “exceptionalism,” American or otherwise. 相似文献
995.
While prior research has examined the relationship between maternal depressive symptoms and child externalizing behaviors, little research has focused specifically on the moderating effects of observed parenting behaviors on this relationship. This study was conducted to investigate the role of emotionally maltreating parenting behaviors, which were hypothesized to exacerbate the strength of the relationship between maternal depressive symptoms and child behavior problems. Maternal depressive symptoms, child externalizing problems, and emotionally maltreating parenting behaviors were assessed in a community sample of 62 mother–child dyads (with children age 8–11 years). Results indicated the overall model was significant, after controlling for maternal race, as was the interaction between maternal depressive symptoms and emotionally maltreating parenting behaviors. Based on these findings, future research is needed to identify potential protective factors that may prevent depressive symptoms from negatively affecting parenting behaviors, with the attendant goal of decreasing risk for emotional maltreatment. 相似文献
996.
Viviane Valdes Anne E. Berens Charles A. Nelson III 《International journal of psychology》2021,56(5):729-738
To current study aimed to estimate the point prevalence and identify correlates of postpartum depression (PPD) in a sample of mothers in Dhaka. A total of 235 participants from low- and middle-SES neighbourhoods in Dhaka completed the Edinburgh Postnatal Depression Scale (EPDS) and other assessments of socioeconomic and psychological factors at 24 weeks postpartum. Regression models were fit to explore potential correlates of PPD. The estimated prevalence of high PPD risk in the current sample is 24.3%. In multivariable linear regression models, recent life events, perceived stress and household resources (e.g., access to cooking gas, telephone, furniture, electricity, television, etc.) were significantly associated with PPD. The association of social support with PPD when controlling for other variables was sensitive to the choice of social support measure, highlighting an important methodological issue. The point prevalence of PPD among poor, urban mothers in Bangladesh ranges from 12.3 to 28.5%, with psychological risk factors and household resources as strong correlates. 相似文献
997.
998.
999.
1000.
Charles Davis 《The Ecumenical review》1987,39(2):163-172