全文获取类型
收费全文 | 29880篇 |
免费 | 803篇 |
专业分类
各国政治 | 1572篇 |
工人农民 | 1157篇 |
世界政治 | 2411篇 |
外交国际关系 | 1153篇 |
法律 | 17404篇 |
中国共产党 | 3篇 |
中国政治 | 247篇 |
政治理论 | 6440篇 |
综合类 | 296篇 |
出版年
2020年 | 365篇 |
2019年 | 434篇 |
2018年 | 586篇 |
2017年 | 681篇 |
2016年 | 717篇 |
2015年 | 529篇 |
2014年 | 614篇 |
2013年 | 3226篇 |
2012年 | 699篇 |
2011年 | 816篇 |
2010年 | 666篇 |
2009年 | 691篇 |
2008年 | 770篇 |
2007年 | 787篇 |
2006年 | 766篇 |
2005年 | 671篇 |
2004年 | 702篇 |
2003年 | 744篇 |
2002年 | 616篇 |
2001年 | 1109篇 |
2000年 | 1029篇 |
1999年 | 867篇 |
1998年 | 482篇 |
1997年 | 393篇 |
1996年 | 356篇 |
1995年 | 343篇 |
1994年 | 395篇 |
1993年 | 358篇 |
1992年 | 533篇 |
1991年 | 591篇 |
1990年 | 552篇 |
1989年 | 541篇 |
1988年 | 539篇 |
1987年 | 577篇 |
1986年 | 571篇 |
1985年 | 550篇 |
1984年 | 503篇 |
1983年 | 529篇 |
1982年 | 394篇 |
1981年 | 367篇 |
1980年 | 298篇 |
1979年 | 418篇 |
1978年 | 292篇 |
1977年 | 246篇 |
1976年 | 231篇 |
1975年 | 234篇 |
1974年 | 244篇 |
1973年 | 226篇 |
1972年 | 194篇 |
1971年 | 181篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
861.
J. Michael Angstadt 《政策研究评论》2020,37(2):244-259
As the emergence of nongovernmental conservation efforts generates conflict among various stakeholders, the causal story that each party articulates regarding conservation and the causes of land degradation reflects their unique interests. This study uses existing literature to evaluate causal stories surrounding a contemporary conservation effort: Montana's American Prairie Reserve. Through qualitative review of web‐based documents and newspaper articles, it generates a preliminary account of key stakeholders' causal stories. The case study suggests that parties who might be disadvantaged by ascribing responsibility for environmental harms in an adversarial fashion may instead elect to articulate causal stories that are more neutral than existing approaches might forecast. The study concludes by suggesting that further development of causal story literature may enable it to better address contemporary conservation efforts. 相似文献
862.
The U.S. electric power sector has experienced a substantial shift of the generation mix since the turn of the century, moving from heavy reliance on coal‐powered generation to one drawing more from natural gas and, more recently, renewables. This transition has been forged by a mix of macroeconomic factors (recession and recovery); technological breakthroughs (horizontal drilling coupled with hydraulic fracturing; improvements in natural gas plant efficiency); clean energy policies at federal, state, and local levels of government; and private sector demands for carbon‐free energy sources. These factors have combined to reduce carbon emissions from electric power generation substantially this century. In this article we examine the extent of this transition, its causes, as well as the distinct American institutional factors steering it, including energy and environmental federalism, electoral politics, and the political economy of clean energy policy enactment and resistance. 相似文献
863.
864.
Folk Johanna B. Brown Larry K. Marshall Brandon D. L. Ramos Lili M. C. Gopalakrishnan Lakshmi Koinis-Mitchell Daphne Tolou-Shams Marina 《Journal of youth and adolescence》2020,49(1):238-251
Journal of Youth and Adolescence - Court-involved youth exhibit high rates of psychiatric symptoms, substance use, and delinquency, yet little is known about the contributing roles of caregiver and... 相似文献
865.
Mastrotheodoros Stefanos Van der Graaff Jolien Deković Maja Meeus Wim H. J. Branje Susan 《Journal of youth and adolescence》2020,49(1):119-135
Journal of Youth and Adolescence - Parent–adolescent conflict can be intense, yet parents and adolescents do not always agree on the intensity of conflict. Conflict intensity tends to change... 相似文献
866.
Walter C. Ladwig III 《Legislative Studies Quarterly》2020,45(3):469-493
Why do political parties in parliamentary systems undertake actions, such as joining a coalition government, that will entail significant costs for their members in subsequent elections? Recent research points to the incentive structures faced by differentially positioned members of a parliamentary party: unlike backbenchers, MPs who hold a ministerial portfolio can use the prerequisites of executive office to shield themselves from the costs of governance. This article tests the theory of executive particularism by examining the electoral fortunes of government ministers in India. Sitting government ministers are found to outperform other candidates; however, tests of causality fail to demonstrate that holding a ministerial portfolio causes this electoral benefit. Instead, it appears that a candidate’s electoral performance enhances the likelihood of being granted a ministerial portfolio in the first place. This finding raises questions about the generalizability of claims that party elites can use ministerial office to shield themselves from the costs of governing. 相似文献
867.
Hayter Christopher S. Rasmussen Einar Rooksby Jacob H. 《The Journal of Technology Transfer》2020,45(1):1-8
The Journal of Technology Transfer - University technology transfer is often associated with formal transmission of science-based inventions, for instance through the licensing of patented... 相似文献
868.
Cerver-Romero Elvira Ferreira João J. Fernandes Cristina 《The Journal of Technology Transfer》2020,45(3):780-805
The Journal of Technology Transfer - This paper explores current trends in knowledge spillover research using scientometric analysis of all papers published in journals indexed in the Web of... 相似文献
869.
870.
Marloes E. M. Vester M.D. Ph.D. Kurt B. Nolte M.D. Ph.D. Gary M. Hatch M.D. Chandra Y. Gerrard M.P.H. B.S. Reinoud D. Stoel Ph.D. Rick R. van Rijn M.D. Ph.D. 《Journal of forensic sciences》2020,65(5):1568-1573
Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs. 相似文献