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   26767篇
  免费   774篇
各国政治   978篇
工人农民   1194篇
世界政治   1968篇
外交国际关系   896篇
法律   16436篇
中国共产党   36篇
中国政治   202篇
政治理论   5526篇
综合类   305篇
  2020年   335篇
  2019年   364篇
  2018年   579篇
  2017年   612篇
  2016年   730篇
  2015年   499篇
  2014年   540篇
  2013年   2428篇
  2012年   719篇
  2011年   743篇
  2010年   531篇
  2009年   631篇
  2008年   726篇
  2007年   771篇
  2006年   742篇
  2005年   983篇
  2004年   732篇
  2003年   641篇
  2002年   596篇
  2001年   942篇
  2000年   860篇
  1999年   712篇
  1998年   416篇
  1997年   339篇
  1996年   323篇
  1995年   302篇
  1994年   357篇
  1993年   323篇
  1992年   515篇
  1991年   574篇
  1990年   515篇
  1989年   525篇
  1988年   506篇
  1987年   516篇
  1986年   530篇
  1985年   500篇
  1984年   431篇
  1983年   453篇
  1982年   346篇
  1981年   343篇
  1980年   264篇
  1979年   344篇
  1978年   249篇
  1977年   211篇
  1976年   185篇
  1975年   185篇
  1974年   206篇
  1973年   193篇
  1972年   162篇
  1971年   152篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
For helpful suggestions and criticism I am grateful to Delf Buchwald (Göttingen), Malte Dießelhorst (Göttingen), Ralf Dreier (Göttingen), Bonnie Litschewski Paulson (Göttingen and St. Louis), Martin Schulte (Münster), Alexander Somek (Vienna), and Kenneth I. Winston (Boston). In correspondence, Walter Ott (Zurich) and Carola Vulpius (Dresden) responded in a most helpful way to my queries.  相似文献   
172.
173.
174.
This paper examines nine cases of “spinback,” the flow back to laboratories of technical advantage from technology transfer activities. The benefits revealed in the cases are discussed and assessed for their value to the participating laboratories and the scientists involved. The objective of this study was to explore and test the feasibility of undertaking a comprehensive study of the value of spinback in order to encourage support for technology transfer activities by middle management in a laboratory. Spinback is defined as the phenomenon by which scientists’ and engineers’ participation in technology utilization activities results in a technically valuable flow back to their laboratories or organizations, thereby increasing or improving techical capability. It was anticipated that this exploration would provide evidence that the phenomenon does occur, with important consequences for the organization.  相似文献   
175.
176.
This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP).  相似文献   
177.
The authors examine the characteristics of threatening and otherwise inappropriate communications sent to members of the U.S. Congress by a sample of 86 subjects, 20 of whom threatened assassination. We quote excerpts from these letters and provide quantitative data on such variables as the volume, duration, form, and appearance of such communications; the enclosures; the subjects' perceived relationships to the recipients; the thematic content of the communications; and the messages and threats communicated. Comparisons between 43 subjects who pursued encounters with members of Congress and 43 who did not revealed 17 factors associated with such pursuit. In this population, threateners were significantly less likely to pursue an encounter than inappropriate letter writers who did not threaten, regardless of the type of threat or the harm threatened. Inappropriate letters to members of Congress are compared with those directed to Hollywood celebrities. Mentally disordered persons writing to public figures often mention and sometimes threaten public figures other than those to whom the letters are addressed, which raises important issues regarding notification of endangered third parties and the sharing of information among protective agencies.  相似文献   
178.
With the rapid growth of cross-border competition among currencies, informed observers predict that the new monetary unions are virtually inevitable in many parts of the world. In fact, predictions of such alliances are misleading and almost certainly wrong. Monetary unions necessarily imply a measure of collective action in the issue and management of money. An alliance requires allies—other states with similar preferences and a disposition to act cooperatively. A survey of proposed monetary unions shows that willing partners among sovereign states are just not all that plentiful. Conceivably some governments could be attracted to less demanding forms of monetary alliance, depending on bargaining context. But prospects for many full new monetary unions are dim at best.  相似文献   
179.
In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling.  相似文献   
180.
Citizen suit provisions, which give proregulatory interests access to the federal courts, can be used by Congress to increase the courts' role in regulatory policy. I analyze 284 environmental regulation bills reported favorably out of committee and show that committee support for citizen suits is a function of the committee's policy goals and the political context in which the bills are generated. These findings indicate that Congress deliberately uses judicial procedures as instruments of political control and that scholars examining judicial policymaking must include legislative goals in the list of explanatory factors.  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