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   18931篇
  免费   597篇
各国政治   754篇
工人农民   1341篇
世界政治   1049篇
外交国际关系   707篇
法律   11148篇
中国政治   52篇
政治理论   4403篇
综合类   74篇
  2021年   56篇
  2020年   200篇
  2019年   218篇
  2018年   1492篇
  2017年   1465篇
  2016年   1321篇
  2015年   330篇
  2014年   266篇
  2013年   1352篇
  2012年   439篇
  2011年   1141篇
  2010年   1272篇
  2009年   890篇
  2008年   971篇
  2007年   941篇
  2006年   294篇
  2005年   334篇
  2004年   442篇
  2003年   396篇
  2002年   273篇
  2001年   379篇
  2000年   338篇
  1999年   289篇
  1998年   200篇
  1997年   143篇
  1996年   125篇
  1995年   172篇
  1994年   169篇
  1993年   151篇
  1992年   218篇
  1991年   208篇
  1990年   195篇
  1989年   214篇
  1988年   182篇
  1987年   208篇
  1986年   182篇
  1985年   204篇
  1984年   167篇
  1983年   171篇
  1982年   136篇
  1981年   125篇
  1980年   93篇
  1979年   151篇
  1978年   108篇
  1977年   97篇
  1976年   76篇
  1975年   68篇
  1974年   77篇
  1973年   78篇
  1972年   60篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
981.
A 37-year-old woman was found dead severely charred in the bedroom of her house. The autopsy revealed as cause of death a strangulation of the neck. On the basis of the decomposition of the body the experts were asked for a statement on the duration of burning. There seems to be only little medicolegal experience on the duration of burning to a defined state of decomposition. Based on observations during cremations published in the literature and experimental burnings a burning time of approximately 20 minutes (after temperatures of more than 700 degrees C had been reached) is supposed to be sufficient to produce the present state of the body.  相似文献   
982.
The impact of crime prevention on commercial burglary in a section of Portland, Oregon is assessed. Using time series analysis, and a control area for comparison, some of the problems of previous crime prevention research are addressed. The results of the study discussed show that not only was there a significant reduction in commercial burglary, but the effect persisted. Several rival hypotheses which could explain this reduction are rejected and suggestions for future research are offered.  相似文献   
983.
The public choice literature contains little formal analysis of the bureaucratic choice of production modes — public or private — of publicly funded services. An important question to be addressed is why some governmental bodies choose to provide a publicly funded service with publicly owned and operated production units whereas other governmental bodies contract with private firms to provide the same publicly funded service. This paper is the first formal attempt to remedy this gap in the literature. We develop a theoretical explanation of the government decision maker's choice between public and private production modes based on utility maximizing behavior. We then examine empirically this choice employing logit analysis. The empirical results, which include several tests for robustness, confirm our theoretical explanation. The results are significant and suggest that non-monetary constraints are an important factor affecting this choice of production modes and that monetary constraints are less influential.  相似文献   
984.
An integrative, ecological model developed by Belsky (1980) implies that to understand child abuse researchers must examine factors at four levels: the individual, the family, the environment, and the culture. This study compared abusive and nonabusive parents at three of these four levels. At the individual level, abusers were found to have lower self-esteem than controls. Also, male abusers were likely to be relatively impulsive and hostile. At the level of the family, abusers described their children as more troublesome than control parents, but they did not perceive them as developmentally delayed. At the level of the environment, abusers identified more intense life stressors than nonabusers. Results of this investigation supported Belsky's argument that child abuse involved multiple factors and levels.  相似文献   
985.
Stidham  Ronald; Carp  Robert A. 《Publius》1988,18(4):113-125
This study explores regionalism in the appointment and decisionmakingpatterns of federal district judges. We begin with an examinationof the general appointment strategies of Ronald Reagan, JimmyCarter, and other recent presidents. The role of local constraintsin this process is emphasized. Next, the behavior of federaldistrict judges appointed by recent presidents is analyzed bycomparing levels of support for civil rights and civil libertiesclaims in cases decided during the 1977–1985 period. TheReagan appointees' support scores are compared with those ofjudges appointed by Carter and other recent Democratic and Republicanpresidents. Comparisons are made in the nation as a whole andalso across circuits and states. Our findings indicate thatthe Reagan appointees are less supportive of civil rights andliberties claims than judges named to the bench by Carter orother recent Democratic and Republican presidents.  相似文献   
986.
Post mortem tissue samples from various human organs (skin, muscle, liver, kidney, brain) were stored at room temperature for a period of one year. During this time the samples were regularly histologically tested. Without any pretreatment of the samples a histological preparation and identification was no longer possible after only a few hours. By the use of a rehydration solution consisting of absolute ethanol (30 ml), aqua dest. (50 ml) and 0.2 M phosphate buffer pH 7.0 (20 ml) a reconstitution and identification was again possible. Further immunhistochemical examinations were also unaffected by the solution. The use of microwave stimulation allowed a reduction of the rehydration process from 24 hours to only 4 hours.  相似文献   
987.
A reversible technique is presented in which the root morphology of missing teeth in skeletonized human remains can be reconstructed for the purpose of radiographic comparison and postmortem identification. In this technique, which is based upon pilot studies with skeletonized mandibles of archival remains, the alveolar socket walls are sealed with a coat of cyanoacrylate cement and injected with a mixture of vinyl polysiloxane and barium sulfate. Radiographs are produced with the radiopaque mixture in place, which highlights the antemortem morphology of the roots. Subsequently, the impression material is removed, resulting in no gross alteration of the evidence. The radiographs made with this technique, as well as the impressions, can be stored for later use at a trial or pending the discovery of antemortem dental evidence.  相似文献   
988.
Between 1987 and 1989 there were approximately 5,000 cases of fatal and injury-sustained road traffic accidents, of which 2.3-3.0% were alcohol related (blood alcohol levels greater than the legal limit of 80 mg% ethanol). The offenders of alcohol-related accidents are mostly Chinese (> 79%), male (> 98%), and more often 30-40 years old. The majority of the alcohol-related accidents (> 74%) took place between 8 P.M. and 4 A.M. in fine weather and light traffic. Rear-end, head-on, and side-on collisions comprised > 60% of all the alcohol-related accidents, and losing control of vehicles approximately 30%. Drunken driving cases for the same period that were not accidents showed a number of characteristics similar to those for accidents. In Singapore, motorcycle riders and pedestrians are more prone to road fatality than other road-user groups. International comparisons of road fatalities per 100,000 population gave Singapore one of the lowest accident rates (8.1-8.4) as compared with countries such as Australia, the United Kingdom, the United States, New Zealand, Canada, and Japan.  相似文献   
989.
990.
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