首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5220篇
  免费   126篇
管理学   920篇
民族学   41篇
人才学   1篇
人口学   406篇
丛书文集   22篇
理论方法论   614篇
综合类   68篇
社会学   2623篇
统计学   651篇
  2023年   47篇
  2022年   28篇
  2021年   36篇
  2020年   102篇
  2019年   164篇
  2018年   148篇
  2017年   222篇
  2016年   153篇
  2015年   145篇
  2014年   156篇
  2013年   842篇
  2012年   208篇
  2011年   249篇
  2010年   169篇
  2009年   146篇
  2008年   160篇
  2007年   193篇
  2006年   172篇
  2005年   162篇
  2004年   163篇
  2003年   129篇
  2002年   147篇
  2001年   123篇
  2000年   96篇
  1999年   93篇
  1998年   66篇
  1997年   68篇
  1996年   55篇
  1995年   52篇
  1994年   45篇
  1993年   61篇
  1992年   54篇
  1991年   50篇
  1990年   51篇
  1989年   52篇
  1988年   50篇
  1987年   39篇
  1986年   41篇
  1985年   29篇
  1984年   51篇
  1983年   38篇
  1982年   42篇
  1981年   41篇
  1980年   37篇
  1979年   31篇
  1978年   25篇
  1977年   19篇
  1976年   20篇
  1975年   20篇
  1974年   13篇
排序方式: 共有5346条查询结果,搜索用时 562 毫秒
101.
Biomonitoring programs for urinary chromium (Cr) typically attempt to evaluate occupational exposure via the inhalation route. This study investigated whether Cr can be detected in the urine of people following the ingestion of soils that contain relatively high concentrations of chromium in chromite ore processing residue (COPR). To evaluate the reasonableness of using urinary monitoring to assess environmental exposure, six volunteers ingested 400 mg of soil/day (low-dose group), two others ingested 2.0 g of soil/day (high-dose group) for 3 consecutive days, and one person ingested a placebo on each of 3 days. The soil and COPR mixture contained concentrations of total chromium (Cr) and hexavalent chromium [Cr(VI)] of 103 ± 20 and 9.3 ± 3.8 mg/kg, respectively. Therefore, the low-dose group ingested 41 μg Cr/day [including 3.7 μg Cr(VI)] and the high-dose group ingested 206 μg Cr/day [including 18.6 μg Cr(VI)] on each of 3 consecutive days. All urine samples were collected and analyzed individually for total Cr on the day prior to dosing, during the 3 days of dosing, and up to the first void 48 h after the last dose. No significant increases in urinary Cr excretion were found when background excretion data were compared with data following each of the 3 days of dosing or in daily mean urine concentrations of the high- vs the low-dose groups. It appears that Cr present in a soil and COPR mixture at Cr doses up to 200 μg/day is not sufficiently bioavailable for biomonitoring of urine to be informative. These results are consistent with previously published findings suggesting that incidental exposure to dusts and soils containing comparable levels of Cr will not result in increased concentrations of Cr in urine.  相似文献   
102.
Urban Ecosystems - Residential yardscapes are at the forefront of human interaction with nature for those living in urban areas across Europe and North America. In recent years a significant amount...  相似文献   
103.
Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light...  相似文献   
104.
105.
Statistics and Computing - Finite Gaussian mixture models are widely used for model-based clustering of continuous data. Nevertheless, since the number of model parameters scales quadratically with...  相似文献   
106.
During imminent threat crises, such as natural disasters, publics have minutes to decide how to respond after receiving a warning. This study advances understanding of publics’ crisis communicative and noncommunicative behaviors in the context of tornadoes through combining and extending two theories: the social-mediated crisis communication (SMCC) model and the situational theory of problem solving (STOPS). Findings from a survey of Southeast U.S. residents (n = 1,585) indicate that STOPS is internally consistent and accurate at measuring its intended outcomes of communicative action in problem solving. However, the STOPS measures do not have a significant relationship with the desirable outcome for imminent threat crisis communication: individuals following government’s protective action guidance about tornadoes. In comparison, the expanded SMCC model predicts individuals’ self-reported compliance. Finally, variables from the SMCC model and tornado-specific variables were integrated into the STOPS model to explain individuals’ communicative engagement. Implications for theory and public relations practice are discussed.  相似文献   
107.
Objective: Despite declining cigarette smoking rates in the US, there is a continued need for tobacco prevention education campaigns to reach young adults. Recognizing the need for improved tobacco control messaging, the University of Texas (UT) System engaged The University of Texas at Austin Center for Health Communication to develop a brand and message that would strengthen tobacco control efforts at its 14 institutions. Methods: This article describes the iterative process involved in creating a brand for tobacco control, including an environmental scan, identifying potential message themes, and creating and refining logos. Results: This article highlights the process of developing a system-wide tobacco control brand. Specifically, the process included coordinating an interdisciplinary team with content and design experts, and presenting ideas to stakeholders for serial feedback and refinement, among others. Conclusions: Ultimately, this project offers a model for other systems of higher education interested in pursuing similar initiatives.  相似文献   
108.
This article presents some of the community-based artwork of a group of men with learning disabilities, who aimed to challenge some of the misconceptions associated with learning disabilities. People with learning disabilities regularly face many forms of direct and indirect stigma. The consequences of such negative perceptions may affect individuals’ social relationships and ensure that barriers are strengthened which prevent their full inclusion. The men in this project used a series of visual and creative methods to challenge some of these misconceptions by telling stories through art, demonstrating skill through photography, using poetry to talk about sexual identity and improvising drama and filmmaking to challenge stigma, and through sculpture expressed their voices. Thus, by doing so, they were able to challenge some of the stigma associated with learning disabilities, indicating that community-based arts research is a valuable way in which to promote the voices of people with learning disabilities.  相似文献   
109.
The use of the term ‘high conflict’ to describe a wide range of family dynamics after separation and divorce has increased significantly over the years. At the moment, no consensus on the definition of high conflict exists. Lack of definitional clarity hinders the ability for legal and mental health professionals to assess, identify, and effectively intervene with this population. Based on a rapid evidence assessment of 65 empirically based social science studies relevant to high conflict, this article positions high-conflict separation and divorce using an ecological transactional model to better understand risk factors and indicators associated with these families. Authors propose a more comprehensive definition that captures the complexity and interactions of various risk factors and indicators on multiple levels. Positioning high-conflict families using an ecological model identifies several points of intervention professionals can use and the fundamental need for collaboration among stakeholders for effective intervention.  相似文献   
110.
This study examined the parallel mediational processes between sensation seeking and parental rules on alcohol, in the emergence of heavy episodic drinking (HED) in adolescents. Data were drawn from a U.K. clustered randomized control trial (control arm only, N ≈ 6,300, Mage at baseline = 12.5). Using parallel process latent growth curve analysis, stricter parental rules at baseline were found to be associated with greater declines in sensation seeking over time and a lower risk of HED at follow‐up (+33 months). Higher initial levels of sensation seeking predicted a faster relaxation of parental rules and a greater risk of HED. By maintaining strict rules about alcohol, parents may promote a positive reduction in sensation seeking and a lower risk of HED.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号