全文获取类型
收费全文 | 4706篇 |
免费 | 146篇 |
专业分类
各国政治 | 150篇 |
工人农民 | 213篇 |
世界政治 | 311篇 |
外交国际关系 | 177篇 |
法律 | 3134篇 |
中国政治 | 24篇 |
政治理论 | 820篇 |
综合类 | 23篇 |
出版年
2023年 | 37篇 |
2021年 | 26篇 |
2020年 | 57篇 |
2019年 | 76篇 |
2018年 | 103篇 |
2017年 | 97篇 |
2016年 | 115篇 |
2015年 | 68篇 |
2014年 | 89篇 |
2013年 | 411篇 |
2012年 | 114篇 |
2011年 | 135篇 |
2010年 | 94篇 |
2009年 | 120篇 |
2008年 | 117篇 |
2007年 | 116篇 |
2006年 | 122篇 |
2005年 | 82篇 |
2004年 | 102篇 |
2003年 | 108篇 |
2002年 | 85篇 |
2001年 | 208篇 |
2000年 | 207篇 |
1999年 | 149篇 |
1998年 | 61篇 |
1997年 | 60篇 |
1996年 | 54篇 |
1995年 | 52篇 |
1994年 | 59篇 |
1993年 | 52篇 |
1992年 | 118篇 |
1991年 | 106篇 |
1990年 | 132篇 |
1989年 | 121篇 |
1988年 | 136篇 |
1987年 | 129篇 |
1986年 | 100篇 |
1985年 | 106篇 |
1984年 | 80篇 |
1983年 | 71篇 |
1982年 | 52篇 |
1981年 | 47篇 |
1980年 | 40篇 |
1979年 | 50篇 |
1978年 | 36篇 |
1976年 | 30篇 |
1975年 | 28篇 |
1974年 | 39篇 |
1973年 | 28篇 |
1970年 | 27篇 |
排序方式: 共有4852条查询结果,搜索用时 15 毫秒
391.
A Linear Poisson Autoregressive Model: The Poisson AR(p) Model 总被引:1,自引:0,他引:1
Time series of event counts are common in political scienceand other social science applications. Presently, there arefew satisfactory methods for identifying the dynamics in suchdata and accounting for the dynamic processes in event countsregression. We address this issue by building on earlier workfor persistent event counts in the Poisson exponentially weightedmoving-average model (PEWMA) of Brandt et al. (American Journalof Political Science 44(4):823843, 2000). We developan alternative model for stationary mean reverting data, thePoisson autoregressive model of order p, or PAR(p) model. Issuesof identification and model selection are also considered. Wethen evaluate the properties of this model and present bothMonte Carlo evidence and applications to illustrate. 相似文献
392.
Raven KP Reay DT Harruff RC 《The American journal of forensic medicine and pathology》1999,20(1):31-36
Over a period of 9 months we examined a series of 50 deaths due to natural and unnatural causes in which there had been endotracheal intubation and chest compression during resuscitation at the scene or in the emergency department shortly before death. In 37 of 50 cases (74%) there were airway injuries directly resulting from the intubation procedure which we documented using a standardized protocol and photography. Specific airway injuries, ranging from petechiae to contusions, included oral injury (28%), posterior pharyngeal injury (16%), epiglottic injury (22%), piriform recess injury (12%), laryngeal and tracheal mucosa injury (64%), strap muscle hemorrhage (14%), and cutaneous injury of the neck (4%). In addition, we recorded the presence of facial (6%) and conjunctival petechiae (21%) and attributed these changes to resuscitative chest compression. No cases had associated fractures of the hyoid or thyroid cartilage. Based on our findings, we conclude that resuscitative intubation can cause artifactual injury that may mimic inflicted injuries caused by neck compression, including strangulation and neck holds. 相似文献
393.
John T. Scott 《The Journal of Technology Transfer》1999,24(1):37-54
The paper explains why the productivity of information technology (IT) in the service sector of the U.S. economy is increased by the provision of infratechnology. The size and growth of the service sector and its investment in IT are discussed, and a key fact and a key inference are developed. The fact: The absorption costs of IT are the vast majority of the IT investment costs to the service sector. The inference: Infratechnology investments are an efficient way to increase both private and social benefits of incurring the cost of implementing IT. 相似文献
394.
395.
396.
397.
398.
399.
400.