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   6012篇
  免费   199篇
各国政治   323篇
工人农民   212篇
世界政治   470篇
外交国际关系   209篇
法律   3531篇
中国共产党   1篇
中国政治   43篇
政治理论   1376篇
综合类   46篇
  2020年   81篇
  2019年   94篇
  2018年   111篇
  2017年   138篇
  2016年   141篇
  2015年   109篇
  2014年   121篇
  2013年   724篇
  2012年   156篇
  2011年   155篇
  2010年   134篇
  2009年   124篇
  2008年   162篇
  2007年   161篇
  2006年   171篇
  2005年   151篇
  2004年   164篇
  2003年   149篇
  2002年   146篇
  2001年   205篇
  2000年   198篇
  1999年   148篇
  1998年   83篇
  1997年   67篇
  1996年   66篇
  1995年   70篇
  1994年   66篇
  1993年   61篇
  1992年   103篇
  1991年   109篇
  1990年   122篇
  1989年   104篇
  1988年   104篇
  1987年   96篇
  1986年   119篇
  1985年   125篇
  1984年   107篇
  1983年   97篇
  1982年   59篇
  1981年   63篇
  1980年   61篇
  1979年   60篇
  1978年   66篇
  1977年   41篇
  1976年   48篇
  1975年   55篇
  1974年   72篇
  1973年   62篇
  1972年   52篇
  1969年   47篇
排序方式: 共有6211条查询结果,搜索用时 15 毫秒
31.
32.
Quadratic pieces of fleece measuring 16 mm2 were soaked with 10 different blood-samples in the dilution steps of 1:1, 1:10, 1:100, 1:1000, respectively, and were tested in blood group typing and identification tests of forensic serology. The above spezified dilutions correspond with 5 microliters, 0.5 microliter, 0.05 microliter and 0.005 microliter of blood, respectively. The detection limit of the microspectrometric test for blood was the dilution 1:10, of the porphyrine test a dilution above 1:100, whereas the preliminary test for blood (peroxidase) succeeded always up to a dilution of 1:1000 and the species determination by the radial immunodiffusion test in agar gels succeeded in most cases op to a dilution of 1:1000. The detection limit of the anti-human globulin inhibition test was between the dilution steps 1:10 and 1:100 when non-titrated and undiluted anti-human globulin serum was used. Gc- and ABO-grouping were possible up to a dilution of 1:100 and were thus the most sensitive grouping systems. Phenotyping of the enzyme-systems and the Gm/Km-system usually required stains with considerably higher blood concentrations i.e. stains of undiluted blood.  相似文献   
33.
Telecommunications regulation has experienced a fundamentalshift from rate regulation to increased reliance on compelledaccess, perhaps best exemplified by the Telecommunications Actof 1996's imposition of no fewer than four new access requirements.Unfortunately, each access requirement is governed by a separateset of rules for determining both the scope and the price ofaccess. The resulting ad hoc regime has created difficult definitionalproblems and opportunities for regulatory arbitrage. In thisarticle we propose a system inspired by the discipline of mathematicsknown as graph theory that integrates all of the different formsof access into a single analytical framework. This system separatesdifferent access regimes into five categories: (1) retail access,(2) wholesale access, (3) interconnection access, (4) platformaccess, and (5) unbundled access. It also provides insightsinto how each type of access complicates the already difficultproblems of network configuration and management and introducesinefficient biases into decisions about network capacity anddesign. The approach we propose also provides insights intothe transaction cost implications of the different types ofaccess. Drawing on the Coasean theory of the firm, our approachexamines the tradeoffs between internal governance costs andthe external transaction costs of providing access to offera theory of network boundaries. This framework shows how accessregulation distorts networks' natural boundaries and providesa basis for evaluating whether private ordering through marketswould lead to more efficient network design.  相似文献   
34.
Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept® oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept® enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall ‘present’/‘not found’ reports calculated as true positives/(true positives + false negatives) were for the amfetamine specific assay 50%, methyl-amfetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques.  相似文献   
35.
36.
37.
Reviews     
R. W. Davies, ed., From Tsarism to the New Economic Policy. Continuity and Change in the Economy of the USSR. London and Basingstoke: Macmillan, 1990, xx + 417 pp., £45.00.

Alastair McAuley, ed., Soviet Federalism, Nationalism and Economic Decentralisation. Leicester and London: Leicester University Press, 1991, ix + 214pp., £38.00.

Loren Graham, ed., Science and the Soviet Social Order. Cambridge, MA and London: Harvard University Press, 1990, ix + 443 pp., £27.95.

Ronald I. McKinnon, The Order of Economic Liberalization: Financial Control in the Transition to a Market Economy. Baltimore, MD, and London: The Johns Hopkins University Press, 1991. xii + 200 pp., £20.00. $32.00.

Mary McAuley, Bread and Justice: State and Society in Petrograd 1917–1922. Oxford: Oxford University Press, 1991, xviii + 461 pp., £45.00.

David Armstrong & Erik Goldstein, eds, The End of the Cold War. London: Frank Cass & Co Ltd, 1990. 216pp., £19.50.

Paul B. Stephan III & Boris M. Klimenko, eds, International Law and International Security: Military and Political Dimensions. A US‐Soviet Dialogue. Armonk, NY, and London: M. E. Sharpe, Inc., 1991, xxii + 362 pp., $90.00.

Richard F. Staar, Foreign Policies of the Soviet Union. Stanford, CA: Hoover Institution Press, 1991, xl + 352 pp., £14.95 p/b.

Robert O. Freedman, Moscow and the Middle East: Soviet Policy Since the Invasion of Afghanistan. Cambridge: Cambridge University Press, 1991, xi + 426 pp., £35.00 h/b, £14.95 p/b.

Galia Golan, Soviet Policies in The Middle East: From World War II to Gorbachev. Cambridge: Cambridge University Press, 1990, ix + 319 pp., £27.50 h/b, £10.95 p/b.

Brian McNair, Glasnost, Perestroika and the Soviet Media. London and New York: Routledge, 1991, x + 231 pp., £35.00.

Shams Ud Din, ed, Perestroika and the Nationality Question in the USSR. New Delhi: Vikas, 1991, xv + 145 pp., £15.95.

Ronald J. Hill & Jan Zielonka, eds, Restructuring Eastern Europe: Towards a New European Order. Aldershot: Edward Elgar, 1990, ix + 226 pp., £28.50.

Aleksa Djilas, The Contested Country: Yugoslav Unity and Communist Revolution 1919–1953. London: Harvard University Press, 1991, v + 259 pp., £27.95 h/b.

Bartlomiej Kamiriski, The Collapse of State Socialism: the Case of Poland. Princeton, NJ: Princeton University Press, 1991, xiv + 264 pp., $39.50 h/b, $14.95 p/b.

David Ost, Solidarity and the Politics of Anti‐Politics. Opposition and Reform in Poland since 1968. Philadelphia, PA: Temple UP, 1990, xi + 279 pp. $34.95.

Roman Laba, The Roots of SolidarityA Political Sociology of Working Class Democratisation. Princeton, NJ: Princeton UP, 1991, xii + 247 pp., $24.95.

Keith Sword, ed, The Soviet Takeover of the Polish Eastern Provinces, 1939–41. London: Macmillan (in association with the School of Slavonic and East European Studies), 1991, xxiii + 318 pp., £45.00.

William B. Husband, Revolution in the Factory: The Birth of Soviet Textile Industry, 1917–20. New York and Oxford: Oxford University Press, 1990, viii + 227 pp. £25.00.  相似文献   

38.
Book Review     
Radical myths and superpower relations in the 1980s

A review of Mark Kaldor, Gerard Holden, and Richard Falk (eds), The New Detente: Rethinking East‐West Relations, Verso, London, 1989.

Paul Taylor and A.J.R. Groom, Global Issues in the United Nations Framework, Basingstoke, Hampshire, The MacMillan Press Ltd., 1989.

Roger A. Coate, Unilateralism, Ideology, and US Foreign Policy: The United States in and out of UNESCO, Lynne Reinner Publishers, London, 1988.

Bary Buzan, Morten Kelstnip, Pierre Lemaitre, Elzbieta Tromer, and Ole Weaver, The European Security Order Recast: Scenarios for the Post‐Cold War Era, Pinter Publishers, London & New York, 1990, pp.x. 282, £8.95 pbk, £30 hbk.  相似文献   

39.
40.
A definitive explanation of "crib" or "cot" death remains unknown. An unusual incidental autopsy finding of agenesis of the corpus callosum in a case presenting as "near miss" sudden infant death syndrome (SIDS) is discussed. Hitherto, only a single case associated with SIDS has been reported in the literature. The condition may be easily missed outside the interest in neuropathology.  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