全文获取类型
收费全文 | 7357篇 |
免费 | 474篇 |
专业分类
各国政治 | 351篇 |
工人农民 | 235篇 |
世界政治 | 487篇 |
外交国际关系 | 237篇 |
法律 | 5128篇 |
中国政治 | 40篇 |
政治理论 | 1314篇 |
综合类 | 39篇 |
出版年
2020年 | 162篇 |
2019年 | 171篇 |
2018年 | 184篇 |
2017年 | 218篇 |
2016年 | 220篇 |
2015年 | 199篇 |
2014年 | 191篇 |
2013年 | 783篇 |
2012年 | 158篇 |
2011年 | 175篇 |
2010年 | 214篇 |
2009年 | 229篇 |
2008年 | 170篇 |
2007年 | 166篇 |
2006年 | 169篇 |
2005年 | 170篇 |
2004年 | 187篇 |
2003年 | 169篇 |
2002年 | 146篇 |
2001年 | 312篇 |
2000年 | 252篇 |
1999年 | 227篇 |
1998年 | 101篇 |
1997年 | 65篇 |
1996年 | 69篇 |
1995年 | 80篇 |
1994年 | 88篇 |
1993年 | 89篇 |
1992年 | 153篇 |
1991年 | 161篇 |
1990年 | 148篇 |
1989年 | 161篇 |
1988年 | 123篇 |
1987年 | 140篇 |
1986年 | 126篇 |
1985年 | 135篇 |
1984年 | 104篇 |
1983年 | 118篇 |
1982年 | 83篇 |
1981年 | 79篇 |
1980年 | 56篇 |
1979年 | 109篇 |
1978年 | 71篇 |
1977年 | 60篇 |
1976年 | 51篇 |
1975年 | 47篇 |
1974年 | 57篇 |
1973年 | 59篇 |
1972年 | 45篇 |
1968年 | 42篇 |
排序方式: 共有7831条查询结果,搜索用时 0 毫秒
171.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined. 相似文献
172.
173.
Sophia K. Chiu M.D. M.P.H. Jessica F. Li M.S.P.H. Kurt B. Nolte M.D. 《Journal of forensic sciences》2020,65(4):1324-1327
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls. 相似文献
174.
175.
Raymond B. Firehock John A. Gentry Julia W. Rogers James M. Simon Jr 《Intelligence & National Security》2018,33(5):774-783
The literature on intelligence analysis contains many references to the ‘review process’, the mechanism by which analysts’ drafts are converted into corporate products. Analysts whose drafts consistently navigate the process quickly and smoothly are regarded as star performers. Divining the practical meaning of organizational definitions of ‘good’ analysis and the personal preferences of specific senior reviewers is not easy, however. Analysts occasionally commit their understanding of reviewers’ stylistic preferences to paper, effectively providing style guides to help others. This essay presents and explains the development and implications of one such guide, which was designed to help analysts in CIA’s Office of Strategic Research in the early 1970s. 相似文献
176.
Which European Union actors are most powerful in the governance of the euro crisis? The euro crisis has reignited the classic debate between intergovernmentalists, who tend to stress the coercive power of dominant member states in the European Council, and supranationalists, who maintain that through the use of institutional power, the Commission, and the European Central Bank turned out the “winners” of the crisis. This article argues that euro crisis governance is best understood not just in terms of one form of power but instead as evolving through different constellations of coercive, institutional, and ideational power that favored different EU actors over the course of the crisis, from the initial fast‐burning phase (2010–2012), where the coercive and ideational power of Northern European member states in the European Council was strongest, to the slow‐burning phase (2012–2016), when greater influence was afforded supranational actors through the use of ideational and institutional power. 相似文献
177.
Philip B. Whyman 《The Political quarterly》2018,89(2):298-305
It is becoming increasingly accepted, not least by the Prime Minister and opposition leadership, that the negotiation of a comprehensive trade relationship with the EU is necessary to prevent the UK economy falling off a ‘cliff edge’. This concern is shaping the UK's strategy towards negotiations with the EU and has provided at least part of the motivation for the UK to consider requesting a transition period to facilitate the Brexit process. But how accurate are these fears? What evidence is there for the existence of a ‘cliff edge’? How disastrous would it be for the UK to revert to trading with the EU on the same basis as most other countries in the world, namely according to World Trade Organisation rules? This article seeks to address these issues and it highlights a number of implications for policy makers which flow from understanding the available evidence a little more clearly. 相似文献
178.
The Department of Government at Essex University provided a favourable environment for the development of Anthony King's work. While his primary interest was the UK, his intellectual interests were far broader in scope and informed by comparative insights. His key work was on political leadership, but he also made crucial contributions on other issues such as ungovernability. He had a particular concern with the quality of government, reflected in the Blunders book he wrote with Ivor Crewe. 相似文献
179.
180.
What drives the polarisation and moderation of opinions? Evidence from a Finnish citizen deliberation experiment on immigration 下载免费PDF全文
MARINA LINDELL ANDRÉ BÄCHTIGER KIMMO GRÖNLUND KAISA HERNE MAIJA SETÄLÄ DOMINIK WYSS 《European Journal of Political Research》2017,56(1):23-45
In the study of deliberation, a largely under‐explored area is why some participants polarise their opinion after deliberation and why others moderate them. Opinion polarisation is usually considered a suspicious outcome of deliberation, while moderation is seen as a desirable one. This article takes issue with this view. Results from a Finnish deliberative experiment on immigration show that polarisers and moderators were not different in socioeconomic, cognitive or affective profiles. Moreover, both polarisation and moderation can entail deliberatively desired pathways: in the experiment, both polarisers and moderators learned during deliberation, levels of empathy were fairly high on both sides, and group pressures barely mattered. Finally, the low physical presence of immigrants in some discussion groups was associated with polarisation in the anti‐immigrant direction, bolstering longstanding claims regarding the importance of presence for democratic politics. 相似文献