全文获取类型
收费全文 | 9284篇 |
免费 | 106篇 |
国内免费 | 18篇 |
专业分类
教育 | 6273篇 |
科学研究 | 1042篇 |
各国文化 | 90篇 |
体育 | 995篇 |
综合类 | 6篇 |
文化理论 | 96篇 |
信息传播 | 906篇 |
出版年
2021年 | 70篇 |
2020年 | 122篇 |
2019年 | 176篇 |
2018年 | 237篇 |
2017年 | 253篇 |
2016年 | 218篇 |
2015年 | 153篇 |
2014年 | 216篇 |
2013年 | 1689篇 |
2012年 | 199篇 |
2011年 | 196篇 |
2010年 | 169篇 |
2009年 | 152篇 |
2008年 | 169篇 |
2007年 | 193篇 |
2006年 | 160篇 |
2005年 | 150篇 |
2004年 | 141篇 |
2003年 | 168篇 |
2002年 | 138篇 |
2001年 | 157篇 |
2000年 | 157篇 |
1999年 | 155篇 |
1998年 | 72篇 |
1997年 | 74篇 |
1996年 | 109篇 |
1995年 | 77篇 |
1994年 | 95篇 |
1993年 | 87篇 |
1992年 | 153篇 |
1991年 | 146篇 |
1990年 | 137篇 |
1989年 | 136篇 |
1988年 | 114篇 |
1987年 | 116篇 |
1986年 | 138篇 |
1985年 | 134篇 |
1984年 | 107篇 |
1983年 | 129篇 |
1982年 | 110篇 |
1981年 | 104篇 |
1980年 | 93篇 |
1979年 | 165篇 |
1978年 | 110篇 |
1977年 | 108篇 |
1976年 | 104篇 |
1975年 | 79篇 |
1974年 | 89篇 |
1972年 | 70篇 |
1971年 | 70篇 |
排序方式: 共有9408条查询结果,搜索用时 31 毫秒
992.
Elisa Ugarte Marigen Narea Daniela Aldoney David G. Weissman Paul D. Hastings 《Child development》2021,92(3):871-888
Latent class analysis and multigroup mediation were used with 8,860 families in Chile to identify risk groups varying in socioeconomic status, family structure, and maternal depression, to determine whether profiles differed in children’s development of externalizing problems (EP) from 35 to 61 months, and maternal parenting that predicted EP. Four groups were identified: one no-risk profile and three risk profiles, impoverished and undereducated, depressed and impoverished, and father-absent and impoverished. All classes differed in EP. Maternal emotional support and harsh parenting were differentially associated with the development of EP across the three risk groups, relative to the low-risk group. Thus, specific constellations of adversities differentially predicted children’s EP and socialization processes mediating links between risk and EP. Implications are discussed. 相似文献
993.
Danica G. Hays Stephanie A. Crockett Rebecca Michel 《Counselor Education & Supervision》2021,60(1):51-72
Counselor educators are well‐equipped to serve as academic leaders, yet little is known about what factors influence their engagement experiences. This grounded theory provides a theoretical model of academic leadership engagement based on interviews with 20 counselor educators with academic leadership experience. Implications for facilitating academic leadership engagement are provided. 相似文献
994.
Sarah G. Curci Linda J. Luecken Marisol Perez Rebecca M.B. White 《Child development》2021,92(5):1785-1800
Socioeconomically disadvantaged neighborhoods increase the risk for poor mental health among residents, yet protective factors may operate alongside risk. This study evaluated the influence of the prenatal neighborhood ethnocultural context on child behavior problems and maternal depressive symptoms. Prenatal maternal role expectations, prenatal culture-specific stress, and postpartum depression (PPD) symptoms were evaluated as mediators. Participants included 322 low-income, Mexican American mother-child dyads. Women (Mage = 27.8) reported on proposed mediators, maternal depressive symptoms, and child behavior problems at 4.5 years. Neighborhood Latinx concentration was obtained from census data. Higher Latinx concentration predicted fewer maternal depressive symptoms and child behavior problems, mediated through role expectations and PPD symptoms. Results suggest prenatal neighborhood context to impact later maternal and child mental health. 相似文献
995.
Michael L. Thomas Gregory G. Brown Virginie M. Patt John R. Duffy 《Educational and psychological measurement》2021,81(1):155
The adaptation of experimental cognitive tasks into measures that can be used to quantify neurocognitive outcomes in translational studies and clinical trials has become a key component of the strategy to address psychiatric and neurological disorders. Unfortunately, while most experimental cognitive tests have strong theoretical bases, they can have poor psychometric properties, leaving them vulnerable to measurement challenges that undermine their use in applied settings. Item response theory–based computerized adaptive testing has been proposed as a solution but has been limited in experimental and translational research due to its large sample requirements. We present a generalized latent variable model that, when combined with strong parametric assumptions based on mathematical cognitive models, permits the use of adaptive testing without large samples or the need to precalibrate item parameters. The approach is demonstrated using data from a common measure of working memory—the N-back task—collected across a diverse sample of participants. After evaluating dimensionality and model fit, we conducted a simulation study to compare adaptive versus nonadaptive testing. Computerized adaptive testing either made the task 36% more efficient or score estimates 23% more precise, when compared to nonadaptive testing. This proof-of-concept study demonstrates that latent variable modeling and adaptive testing can be used in experimental cognitive testing even with relatively small samples. Adaptive testing has the potential to improve the impact and replicability of findings from translational studies and clinical trials that use experimental cognitive tasks as outcome measures. 相似文献
996.
Joseph G. Eisenhauer 《Teaching Statistics》2021,43(1):21-27
Statistical methods are increasingly being used to integrate findings from the ever‐expanding universe of empirical research. Meta‐analysis encompasses various techniques for synthesizing summary statistics, and mega‐analysis pools raw data across studies. This paper offers an introduction to meta‐analysis and mega‐analysis that complements the study of analysis of variance (ANOVA). After a brief conceptual discussion, we provide simple numerical examples. 相似文献
997.
A bibliography is traditionally characterized by the judgments, bounded by explicit selection criteria, made by a single compiler. Because these criteria concern the attributes ascribed to a work and the needs of readers, bibliographic work is largely conceptual even across technological eras and domains. Yet, the development of networked information services, made possible by WWW infrastructure, has enabled very large numbers of people to discover, organize, and publish information, including bibliographies. Indeed, bibliographies, or at least bibliography-like artifacts, are a common genre of website, often published by people without specialized skills in information organization who follow non-rigorous selection procedures. Nevertheless, even if the items from these lists are poorly selected and described, this publishing activity is fundamentally important because it structures information locally, creating a patchy network of secondary access points. In turn, these access points enable information discovery, the formation and development of communities of interest, the estimation of document relevance by search engines, and so on. In sum, this activity, and the enabling technical infrastructure, invites bibliographies to take on new interactive possibilities. The aim of this article is to extend the traditional view of bibliography to encompass collaborative possibilities for wide, or narrow, participation in the shaping of bibliographies and the selection of items. This is done by examining the nature of bibliography on the Web, by proposing a conceptual model that opens bibliography to participatory practices, and by discussing a case study where a team sought to develop a bibliography of electronic resources. This examination reveals splendid opportunities for expanding the notion of bibliography with participatory policies while remaining true to its ancient roots. 相似文献
998.
An operational prototype inhomogeneous distributed database system has been built to provide homogeneous access for researchers and managers of science policy to data on research projects held in three countries. The architecture is sufficiently general not only to accommodate additional countries and databases on research projects, but also to provide a general framework for other international collaborative projects aimed at the provision of information. The design exhibits an optimal compromise between sufficient data to satisfy a retrieval request and the minimal data for transmission to maintain the database. 相似文献
999.
1000.