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   13685篇
  免费   651篇
各国政治   544篇
工人农民   463篇
世界政治   1024篇
外交国际关系   411篇
法律   9221篇
中国共产党   1篇
中国政治   89篇
政治理论   2530篇
综合类   53篇
  2021年   86篇
  2020年   235篇
  2019年   281篇
  2018年   295篇
  2017年   372篇
  2016年   363篇
  2015年   301篇
  2014年   337篇
  2013年   1239篇
  2012年   312篇
  2011年   397篇
  2010年   346篇
  2009年   377篇
  2008年   372篇
  2007年   330篇
  2006年   359篇
  2005年   321篇
  2004年   332篇
  2003年   309篇
  2002年   311篇
  2001年   599篇
  2000年   517篇
  1999年   375篇
  1998年   214篇
  1997年   188篇
  1996年   150篇
  1995年   164篇
  1994年   187篇
  1993年   185篇
  1992年   269篇
  1991年   292篇
  1990年   271篇
  1989年   265篇
  1988年   276篇
  1987年   258篇
  1986年   316篇
  1985年   294篇
  1984年   233篇
  1983年   237篇
  1982年   136篇
  1981年   148篇
  1980年   105篇
  1979年   160篇
  1978年   101篇
  1977年   96篇
  1976年   84篇
  1974年   108篇
  1973年   87篇
  1972年   88篇
  1970年   73篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
We report a case of rapid death from thrombotic thrombocytopaenic purpura (TTP) in a young pregnant lady who developed full blown symptoms soon after caesarean section. Extensive intramyocardial confluent haemorrhages and widespread microthrombi in heart, brain, adrenals and kidney were found at autopsy. Thrombotic thrombocytopaenic purpura is an uncommon condition, which carries a high fatality rate if untreated. Awareness of this syndrome together with its high risk of sudden death underlines the importance of rapid diagnosis and treatment.  相似文献   
33.
A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.  相似文献   
34.
The polymerase chain reaction (PCR) method of specific gene amplification was used in casework to synthesize millions of copies of the polymorphic second exon of the human leukocyte antigen (HLA)-DQ alpha (or DQA1) locus from a variety of evidence samples. The HLA-DQ alpha allelic variants in the amplified deoxyribonucleic acid (DNA) were determined in a rapid non-radioactive test by hybridization to sequence-specific oligonucleotide probes in both the dot-blot and reverse dot-blot formats. This genetic typing system has been subjected to blind proficiency testing; the performance of this test in the analysis of experimentally mixed samples was also evaluated. As of August 1990, over 250 cases have been tested and more than 2000 individual evidence (bloodstains, semen stains, individual hairs, bone fragments, and tissue sections) and reference samples have been analyzed. The first 198 of these cases are summarized in this paper; in 65% of the cases with conclusive results a suspect was included, and in 35%, all suspects were excluded. Individual cases as well as some of the general issues relating to forensic science analysis and this genetic typing system are discussed. The high rate of exclusion reported here combined with the ability of PCR to type old evidence samples suggests the relevance of this genetic test for postconviction review; two cases in which the convicted suspect was excluded are discussed.  相似文献   
35.
36.
Conclusion So can the Scots learn from Woolf? The answer must be in the affirmative, for his review points up similar problems to those we encounter here. There is no room for complacency in the civil justice system in Scotland, particularly in the field of Information Technology, where court systems and expertise are sadly lacking. It is clear that there is a need for a system of case management in all civil courts, targeted in particular areas or on particular cases, but only after a rigorous reappraisal of court timetabling; and that the public will lose confidence in a civil justice system which does not meet their needs for speedy and affordable decisions, perhaps by turning their backs on it and seeking means of Alternative Dispute Resolution. As for written pleadings, perhaps the most that can be said is that the case for their complete abolition is “not proven”, but that thestatus quo should not be maintained is beyond reasonable doubt. Sheriff of Lothian and Borders at Edinburgh; Member, Sheriff Court Rules Council.  相似文献   
37.
The primary aim of this paper is to review the literature on preadolescent friendships in order to examine the relationship between preadolescent friendships and social support in adulthood. Social supports are important to health, both directly and as a stress buffer. Few studies, however, have specifically examined adult social supports from the perspective of their developmental precursors and critical developmental periods. Some data indicate that the preadolescent period may be of particular importance to the development of adult social skills and ties. Observational and empirical studies of preadolescent peer relationships, and in particular best friendships, suggest unique and critical contributions to adult social relatedness. Present research is suggestive but is insufficient to validate preadolescence as a critical period in adult social relatedness. Our review has implications for better understanding the mechanisms by which preadolescent friendships effect adult social support—an important mediator of the effects of stress on health. Further longitudinal study is needed.Received Ph.D. from University of Maryland. Research interests are social supports and psychological responses to trauma and disaster.Received M.D. from Yale University. Research interests are social supports and traumatic stress.  相似文献   
38.
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   
39.
Abstract. Palle Svensson in this issue of EJPR has objected to the characterisation of Danish voters made by Franklin and others who, in various publications, expounded the thesis that on issues of low salience, referendum votes tend to follow party lines. Svensson finds evidence that the Maastricht Treaty was not an issue of low salience to Danish voters in the ratification referendums conducted there, and gives other details of the evolution of public opinion regarding Europe that clarify the circumstances in which our thesis should apply. In the light of his arguments, this Comment presents a more nuanced version of the thesis that learns from the Danish case, and should be of greater utility than our earlier version in helping to interpret the role of government standing in referendum outcomes.  相似文献   
40.
A dissecting intramural haematoma of the coronary artery is an infrequent cause of sudden and unexpected death. Most cases are women and in a significant number of these women, the haematoma occurred at term to 80 days postpartum. Because the intimal rupture and communication with the lumen were not found in most of the cases, the site of rupture has been considered to be a vasa vasorum. The authors report on a case of one woman who was at a later postpartum period (106 days). The microscopic finding of the dissected coronary artery revealed two intimal tears in a section. The case showed that the dissecting intramural haematoma of the coronary artery is caused not only by the rupture of the vasa vasorum but also by the rupture of the intima.  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