全文获取类型
收费全文 | 10129篇 |
免费 | 201篇 |
国内免费 | 1篇 |
专业分类
管理学 | 1354篇 |
民族学 | 48篇 |
人才学 | 1篇 |
人口学 | 903篇 |
丛书文集 | 45篇 |
理论方法论 | 977篇 |
综合类 | 155篇 |
社会学 | 4657篇 |
统计学 | 2191篇 |
出版年
2023年 | 74篇 |
2021年 | 66篇 |
2020年 | 189篇 |
2019年 | 264篇 |
2018年 | 254篇 |
2017年 | 369篇 |
2016年 | 285篇 |
2015年 | 223篇 |
2014年 | 252篇 |
2013年 | 1805篇 |
2012年 | 345篇 |
2011年 | 296篇 |
2010年 | 259篇 |
2009年 | 226篇 |
2008年 | 283篇 |
2007年 | 283篇 |
2006年 | 242篇 |
2005年 | 203篇 |
2004年 | 199篇 |
2003年 | 175篇 |
2002年 | 182篇 |
2001年 | 204篇 |
2000年 | 185篇 |
1999年 | 170篇 |
1998年 | 151篇 |
1997年 | 146篇 |
1996年 | 144篇 |
1995年 | 126篇 |
1994年 | 111篇 |
1993年 | 145篇 |
1992年 | 160篇 |
1991年 | 132篇 |
1990年 | 140篇 |
1989年 | 119篇 |
1988年 | 116篇 |
1987年 | 115篇 |
1986年 | 105篇 |
1985年 | 95篇 |
1984年 | 120篇 |
1983年 | 104篇 |
1982年 | 98篇 |
1981年 | 68篇 |
1980年 | 102篇 |
1979年 | 114篇 |
1978年 | 77篇 |
1977年 | 85篇 |
1976年 | 76篇 |
1975年 | 88篇 |
1974年 | 71篇 |
1972年 | 62篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Charles W. Griffiths Chris Dockins Nicole Owens Nathalie B. Simon Daniel A. Axelrad 《Risk analysis》2002,22(4):679-688
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure. 相似文献
32.
Assessing reoffense risk with juvenile sexual offenders 总被引:1,自引:0,他引:1
This article summarizes a two-year study of juvenile sexual offenders in Washington. Both community-based and institution-based treatment programs were evaluated. A typical profile of the juvenile sexual offender is offered, as well as recidivism data from a mean 20-month follow-up period. 相似文献
33.
Abstract Agroforestry, the practice of raising crops and trees together in ways that are mutually beneficial, provides farmers with an alternative to more conventional farming practices. In this paper, we apply Bourdieu's concepts of “field” and “habitus” in an attempt to better understand the practice of farming and the role that agroforestry may have in farming systems. Analysis is based on qualitative and quantitative interviews of farmers and other key informants in two regions, Fox‐Wyaconda Watershed in northeast Missouri and Scott County in southeast Missouri. Within the field of farming, farmers emphasized the importance of economic, family and rental relations. Important habitus considerations include different interpretations of what constitutes farming and what constitutes forestry. Based on Bourdieu's theoretical framework, we offer three alternative paths of social change that may lead to more widespread utilization of agroforestry. 相似文献
34.
This paper reports on an evaluation of the Cornwall Young Carers project (jointly funded by social services and the Cornwall and Isles of Scilly Health Action Zone), conducted during the period 2000–2002. A diverse range of methodological approaches were adopted (comparative national statistics, local pilot study, monthly and quarterly data capturing instruments, and a service user focus group) in monitoring and evaluating the project's high level statements/outcomes. Four evaluative themes are discussed, namely: identification of young carers; assessment of young carers' needs; direct service provision; and partnership working. Recommendations and action steps are proposed with a view of informing future planning and service delivery, as well as developing an ethos of integrating evaluation into everyday practice for the Cornwall Young Carers Project. Overall, the project has made significant progress in meeting and exceeding its original targets. The fact that the project has been able to identify 202 new young carers over this period is a key milestone in demonstrating the critical need for the project's services. It is suggested that existing referrals are only the ‘tip of the iceberg’ for work with young carers in Cornwall. 相似文献
35.
36.
I. M. Endresen B. Ellertsen C. Endresen A. M. Hjelmen R. Matre H. Ursin 《Work and stress》1991,5(3):217-227
This study concerned the immunological correlates of stress and work. Self reported stress, emotional state, ego-strength, and defensiveness were examined in relation to measures of cellular immunity (T-cell response to Con A and number of T4 and T8 cells) and humoral immunity (concentrations of immunoglobulins and complement components in plasma) in a group of 96 Norwegian female bank employees. The analyses showed that workload, the stress factor with the highest group mean, was associated with number of T-cells, while strain due to body posture during work was related to concentrations of IgM and C3. Further, depression was significantly correlated with IgM concentration and T-cell number, and anxiety with C3 concentration. T-cell activity was the immunological parameter most consistently associated with psychological well-being, showing positive correlations with defensiveness and ego-strength and negative correlations with anxiety and depression. In conclusion, T-cell number and concentrations of IgM and C3 were sensitive to both work-related stress experience and emotional distress. Coping abilities, indicated by the MMPI Ego-strength scale and emotional distress, were reflected in T-cell activity; insufficient coping was associated with low T-cell activity. 相似文献
37.
38.
Rex Forehand Deborah J. Jones Gene H. Brody Lisa Armistead 《Journal of marriage and the family》2002,64(4):1012-1023
This study examined the unique and interactive roles of mother and teacher depressive symptoms in child adjustment in 277 African American single mother‐headed families, as well as whether the associations differed depending on the age and gender of the child. Findings revealed a significant association between maternal depressive symptoms and child depressive symptoms in girls, but not boys. Moreover, the combination of higher levels of both mother and teacher depressive symptoms was associated with the highest level of child depressive symptoms and, for younger children, externalizing symptoms. The importance of considering the multiple social contexts in which children interact is discussed. 相似文献
39.
40.