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   12237篇
  免费   372篇
各国政治   573篇
工人农民   515篇
世界政治   721篇
外交国际关系   379篇
法律   7904篇
中国共产党   3篇
中国政治   90篇
政治理论   2335篇
综合类   89篇
  2020年   155篇
  2019年   191篇
  2018年   269篇
  2017年   307篇
  2016年   292篇
  2015年   212篇
  2014年   223篇
  2013年   1232篇
  2012年   307篇
  2011年   322篇
  2010年   261篇
  2009年   287篇
  2008年   350篇
  2007年   295篇
  2006年   350篇
  2005年   308篇
  2004年   309篇
  2003年   282篇
  2002年   296篇
  2001年   428篇
  2000年   380篇
  1999年   284篇
  1998年   153篇
  1997年   163篇
  1996年   144篇
  1995年   146篇
  1994年   137篇
  1993年   162篇
  1992年   254篇
  1991年   275篇
  1990年   245篇
  1989年   238篇
  1988年   237篇
  1987年   250篇
  1986年   267篇
  1985年   266篇
  1984年   238篇
  1983年   236篇
  1982年   132篇
  1981年   123篇
  1980年   97篇
  1979年   138篇
  1978年   106篇
  1977年   97篇
  1976年   76篇
  1975年   89篇
  1974年   104篇
  1973年   95篇
  1972年   87篇
  1968年   84篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
In the wake of the Supreme Court's decision in Aviall—that potentially responsible parties (PRPs) are not permitted to seek contribution from other PRPs under CERCLA unless they have been sued or otherwise settled their CERCLA liability—PRPs and the courts have struggled to identify a remedy for those that voluntarily undertake cleanup of contaminated sites. The Atlantic Research decision resolves a conflict among the circuits and clarifies that PRPs voluntarily incurring cleanup costs pursuant to CERCLA, can maintain an action for cost recovery against other PRPs. The authors discuss the current legal landscape regarding actions for cost recovery as presented in Atlantic Research.  相似文献   
992.
Abstract: The Quantifiler® Duo DNA Quantification kit enables simultaneous quantification of human DNA and human male DNA as well as detection of inhibitors of PCR in a single real-time PCR well. Pooled human male genomic DNA is used to generate standard curves for both human (ribonuclease P RNA component H1) and human male (sex determining region Y) specific targets. A shift in the cycle threshold (CT) values for the internal positive control monitors the presence of PCR inhibitors in a sample. The assay is human specific and exhibits a high dynamic range from 0.023 to 50 ng/μL. In addition, the multiplex assay can detect as little as 25 pg/μL of human male DNA in the presence of a 1000-fold excess of human female DNA. The multiplex assay provides assessment of the DNA extract and guidance for the selection of the appropriate AmpFℓSTR® Amplification Kit to obtain interpretable short tandem repeat profiles.  相似文献   
993.
994.
The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.  相似文献   
995.
996.
997.
998.
999.
Although data are inconclusive, popular perception has linked military combat, posttraumatic stress disorder (PTSD), and criminal behavior. This paper discusses the multifactorial elements of this association that include both conscious and unconscious parameters of psychologic functioning. Testimony on combat-related PTSD has been presented in the courtroom to support veterans' claims of not guilty by reason of insanity (NGRI) and diminished capacity and for consideration during judicial sentencing. Because there is a known connection between the degree of combat involvement and PTSD, verification through collateral sources of the veteran's report of combat experiences is an important component of forensic assessment. The DSM-III-defined diagnosis of PTSD and the presence of a dissociative state have particular relevance in NGRI determinations. In other aspects of the judicial process demonstration of the absolute presence or absence of PTSD is often irrelevant and should be replaced by efforts to establish plausible links between provable combat experiences and the circumstances of the crime.  相似文献   
1000.
This paper investigates the performance of liability rules in two-party stochastic externality problems where negotiations are feasible and side payments are based on the realized level of externalities. Results show that an increase in polluter liability does not necessarily increase safety or efficiency in cases where the polluter is risk neutral. Complete polluter liability is found to yield Pareto optimality. When either party is risk averse, an increase in polluter liability may sometimes reduce safety and efficiency. If the polluter is risk neutral and the victim is risk averse, Pareto optimality is only achieved by assigning full liability on the polluter, i.e. giving the victim complete property rights to a clean environment. If the polluter is risk averse and the victim is risk neutral, no level of polluter liability is optimal. In this case, optimality can only be achieved through a contract on abatement activities, such that the risk-averse polluter receives a guaranteed payment regardless of the stochastic outcome.  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