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   25852篇
  免费   1592篇
各国政治   1052篇
工人农民   1121篇
世界政治   1852篇
外交国际关系   796篇
法律   17727篇
中国共产党   3篇
中国政治   176篇
政治理论   4560篇
综合类   157篇
  2021年   121篇
  2020年   528篇
  2019年   581篇
  2018年   739篇
  2017年   791篇
  2016年   849篇
  2015年   693篇
  2014年   736篇
  2013年   2629篇
  2012年   678篇
  2011年   781篇
  2010年   828篇
  2009年   835篇
  2008年   723篇
  2007年   694篇
  2006年   795篇
  2005年   632篇
  2004年   634篇
  2003年   550篇
  2002年   575篇
  2001年   973篇
  2000年   859篇
  1999年   696篇
  1998年   363篇
  1997年   285篇
  1996年   278篇
  1995年   310篇
  1994年   292篇
  1993年   277篇
  1992年   479篇
  1991年   499篇
  1990年   472篇
  1989年   467篇
  1988年   471篇
  1987年   405篇
  1986年   477篇
  1985年   483篇
  1984年   424篇
  1983年   370篇
  1982年   288篇
  1981年   256篇
  1980年   242篇
  1979年   337篇
  1978年   190篇
  1977年   159篇
  1976年   133篇
  1975年   155篇
  1974年   182篇
  1973年   136篇
  1972年   121篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
121.
122.
HIV infection is now perceived as the end stage of a chronic disease that is spreading most rapidly among blacks and Hispanics. The politics of the HIV epidemic in the 1980s were dominated by four interacting factors: fear and fascination; who had the disease and to whom it seemed to be spreading; the endemic problems of United States social policy; and the impact on policy of advances in scientific knowledge. This paper analyzes the political history of each of these factors and describes the dominant policies of the federal government and the states regarding HIV in the areas of surveillance, prevention, research, and financing. Four uncertainties will have a profound influence on the future politics of the HIV epidemic: how the states and the federal government will address the general problems of paying for the care of people with chronic diseases and providing access to care for the uninsured and the underinsured; the number and distribution of the sexual behaviors that transmit infection with HIV and the effectiveness of policies to persuade people to modify these behaviors; precisely who uses addictive drugs and the effectiveness of measures to change their behavior; and the natural history of the virus.  相似文献   
123.
124.
Postmortem changes in sulfide concentrations in body tissues were examined in autopsied rats exposed to hydrogen sulfide concentrations of 550 to 650 ppm, and in nonexposed rats and humans. Analyses were made by gas chromatography, following an extractive alkylation. Sulfide concentrations in the blood, liver, and kidneys of rats increased in both the exposed and nonexposed groups, depending on the lapse of time after death. On the other hand, the lung, brain, and muscle showed little or no change in sulfide concentration with elapse of time after death. The data obtained from human tissues were almost the same as those for rats, except data for blood, in which no or little increase of sulfide was observed.  相似文献   
125.
A 22-year-old Korean soldier, who had received blows to the neck and epigastrium from an officer 10 h earlier, suddenly died after massive hematemesis. He had been in relatively good health except for episodes of blood-tinged vomiting approximately 5 and 7 months prior to this event. Postmortem examination revealed angiodysplasia involving the gastroesophageal junction, and the stomach was distended with blood. No abnormal findings were present around the whole viscera, and the duodenum was free of blood. The pathologic significance of upper gastrointestinal angiodysplasia as a potential source of bleeding and a chronologic correlation between the trauma and bleeding are discussed.  相似文献   
126.
127.
128.
129.
De Vault  James M. 《Public Choice》2002,110(1-2):1-22
This study examines the unfair trade decisions of the InternationalTrade Commission (ITC) and how they have been affected by Congress.It begins by identifying the means Congress can use to influenceITC decisions and then estimates both the extent to which thesemeans have been used and the extent to which they have shaped theITC's behavior. The study reaches two conclusions. First, Congresshas tried to shape the ITC's behavior, but it has not tried tomicromanage this behavior. Second, while the ITC's behavior hasbeen influenced by Congress, congressional influence is not asimportant as other factors, such as statutory criteria.  相似文献   
130.
Presented in this paper are the initial results involving the use of the nose or outer ear as temperature measurement sites to determine the postmortem period of the human corpse. Simple mathematical models for both sites are developed based on cooling curves of five corpses. Analysis of errors between actual and calculated postmortem intervals suggest that in its present form, the described methods would not be suitable for use in accurately determining the time since death of human corpses.  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