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   23218篇
  免费   1260篇
各国政治   1089篇
工人农民   1050篇
世界政治   1515篇
外交国际关系   769篇
法律   15590篇
中国共产党   2篇
中国政治   142篇
政治理论   4186篇
综合类   135篇
  2020年   476篇
  2019年   507篇
  2018年   650篇
  2017年   693篇
  2016年   775篇
  2015年   576篇
  2014年   636篇
  2013年   2459篇
  2012年   588篇
  2011年   623篇
  2010年   640篇
  2009年   661篇
  2008年   643篇
  2007年   655篇
  2006年   668篇
  2005年   560篇
  2004年   545篇
  2003年   495篇
  2002年   518篇
  2001年   873篇
  2000年   761篇
  1999年   636篇
  1998年   314篇
  1997年   245篇
  1996年   260篇
  1995年   248篇
  1994年   238篇
  1993年   235篇
  1992年   400篇
  1991年   432篇
  1990年   419篇
  1989年   396篇
  1988年   423篇
  1987年   399篇
  1986年   444篇
  1985年   423篇
  1984年   351篇
  1983年   329篇
  1982年   242篇
  1981年   234篇
  1980年   198篇
  1979年   319篇
  1978年   188篇
  1977年   156篇
  1976年   126篇
  1975年   171篇
  1974年   199篇
  1973年   156篇
  1972年   129篇
  1971年   117篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
All records from the Danish Medicolegal Council concerning drivers suspected for drug influences were examined for the 5 year period 1981-1985. 461 records were included, 62 women and 399 men. In 250 cases drugs from more than one of ten groups had been taken thus making 786 combinations of drug/driving. The major drug group was benzodiazepines, accounting for 65% of all drug intake. Opioids also contributed substantially, found in 38% of the cases. A traffic accident had occurred in 180 (39%) of the records. Drivers who had been taking antidepressives were involved in an accident in 67%, significantly above the mean. For benzodiazepines, the corresponding percentage was 43%, while for opioids it was only 23%, significantly below the mean. This striking difference has been demonstrated in most of the studies concerning drugs in traffic. It may support the hypothesis that opioids do not necessarily make driving dangerous, as do antidepressives, barbiturates and especially benzodiazepines.  相似文献   
162.
In the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.  相似文献   
163.
One of the remedies sought by state and local officials for the growing burden of federal mandates is a mandate reimbursement law. A major purpose of mandate reimbursement is to deter Congress from imposing excessive costs on state and local governments by making it fully accountable for its actions. The paper begins by extending the economic theory of grants to mandates and reimbursed mandates. It goes on to assess the benefits and costs of mandate reimbursement, and to distinguish mandates that should be reimbursed, should a reimbursement program prove desirable, from those that should not. Then, using the economic theory of grants and mandates, the paper compares reimbursed mandates with two alternatives for accomplishing the same objective, compensating grants and procedural rules. It concludes that the latter are more promising than mandate reimbursement.  相似文献   
164.
165.
166.
167.
This paper reviews China's recent efforts to enact a competitionpolicy (antitrust) law. We focus on three issues: (1) What isthe substance of the proposed law, and how does it differ fromexisting antitrust law in other countries, (2) How will thelaw be implemented or enforced, and how will those who mustimplement this law interpret their mandate, and (3) What willbe the likely effects of this law given China's unique historyand cultural heritage. We emphasize China's economic, legaland regulatory contexts in which an antitrust law may be enforced.Our central focus is the problem of establishing a substantiveand procedural legal framework that is incentive-compatiblewith economic efficiency and growth. The draft law could beimproved, both to increase its clarity and to make its enforcementmore consistent with the goal of achieving improvements in economicefficiency. Nevertheless, there is much merit in the draft,especially its strong focus on reducing anticompetitive practicesof state-owned enterprises (SOEs) and other government bodies.However, our major difficulty with the new law is that, in theabsence of a tradition of reliance on the rule of law, Chineseand foreign enterprises will find it very difficult to relyon the antitrust statute or the actions of the courts in Chinaas a basis for predicting the antitrust liability that mightresult from various business practices. Therefore, the principalvector by which antitrust law (or indeed any law) affects economicbehavior is absent from the Chinese scene. Unless the bureaucracythat enforces the new antitrust law actively pursues a policyof consistent enforcement based on written guidelines, staredecisis, or other sources of predictability, the substance ofthe statute itself will have little significance. That outcomewould represent a significant loss for the economic welfareof the Chinese people.  相似文献   
168.
This article surveys the voluminous economic literature on commoditybundling. While bundling has been widely studied, the vast majorityof the literature has focused on theoretical treatments of bundlingthat demonstrate a wide range of reasons why firms might engagein bundling. These papers generally contain restrictive assumptions,including assumptions regarding the existence of monopoly insome markets, and the nature of rivalry in others. The modelscontained in these papers also generally suppress the more obviousand ubiquitous reasons firms may use bundling. Moreover, thesemodels have not been subject to robustness checks, nor havetheir assumptions been tested empirically. This review of theeconomic literature generally confirms the US Solicitor General'sview in 3M v. LePage's regarding the underdeveloped state ofthe economics literature and its position that the US SupremeCourt should defer promulgation of antitrust standards for bundling.While the literature has demonstrated the possibility that bundlingcan generate anticompetitive harm, it does not provide a reliableway to gauge whether the potential for harm would outweigh anydemonstrable benefits from the practice. As a result, the widespreadapplication of the antitrust laws to bundling by firms can generatesignificant error costs by erroneously condemning or deterringefficient business practices. In the future, economists shouldseek to expand their understanding of both the anticompetitiveand procompetitive reasons firms engage in bundling. This willentail studying the reasons why bundling is adopted by firmswithout market power, relaxing the assumption of monopoly intheoretical models, and generating testable hypotheses and thedata to test them.  相似文献   
169.
170.
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