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   1085篇
  免费   24篇
各国政治   48篇
工人农民   46篇
世界政治   61篇
外交国际关系   25篇
法律   795篇
中国政治   21篇
政治理论   106篇
综合类   7篇
  2023年   4篇
  2022年   5篇
  2021年   9篇
  2020年   18篇
  2019年   25篇
  2018年   24篇
  2017年   23篇
  2016年   32篇
  2015年   18篇
  2014年   17篇
  2013年   77篇
  2012年   30篇
  2011年   29篇
  2010年   23篇
  2009年   19篇
  2008年   28篇
  2007年   16篇
  2006年   17篇
  2005年   28篇
  2004年   42篇
  2003年   37篇
  2002年   25篇
  2001年   101篇
  2000年   67篇
  1999年   73篇
  1998年   35篇
  1997年   4篇
  1996年   3篇
  1995年   8篇
  1994年   4篇
  1993年   7篇
  1992年   21篇
  1991年   18篇
  1990年   39篇
  1989年   26篇
  1988年   29篇
  1987年   23篇
  1986年   14篇
  1985年   13篇
  1984年   8篇
  1983年   8篇
  1982年   11篇
  1981年   8篇
  1980年   4篇
  1979年   11篇
  1978年   7篇
  1973年   2篇
  1971年   4篇
  1970年   3篇
  1968年   2篇
排序方式: 共有1109条查询结果,搜索用时 15 毫秒
951.
952.
The relationship between knowledge and power is examined in this article in terms of the social science literature base on Arab countries. It is argued that knowledge imposes normative constraints on the exercise of power, and the exercise of power is dependent on the lack of knowledge. This is examined in terms of the knowledge base on Iraq and Palestine, the two countries in the Arab world most decimated in the post-World War II era by the exercise of external power politics. The study is organized in three phases: (1) delimiting the population of scholarly literature in the social sciences on the Middle East by country; (2) drawing representative samples of scholarly literature on Iraq and Palestine from this population; and (3) content analysis of the samples. Jacqueline S. Ismael is a professor of social work at The University of Calgary. She has published a number of articles and monographs on social change in the Middle East, as well as several works on Canadian social policy. She is co-author with Tareq Y. Ismael ofThe People’s Democratic Republic of Yemen: The Politics of Socialist Transformation (1986),Government and Politics in Islam (1986),Politics and Government in the Middle East andNorth Africa (1991), andThe Gulf War and the New World Order (1994). Her most recent work isKuwait: Dependency and Class in a Rentier State (1993). Tareq Y. Ismael is a professor of political science at The University of Calgary. He has written extensively on Middle East politics, the international relations of the Middle East, and ideology in the Arab world. His recent publications includeInternational Relations of the Contemporary Middle East (1986),Middle East Studies: International Perspectives on the State of the Art (1990),The Communist Movement in Egypt (1990),Politics and Government in the Middle East and North Africa (1991), andThe Gulf War and the New World Order (1994).  相似文献   
953.
The effect of carbon monoxide (CO) inhalation on plasma levels of uric acid and hypoxanthine in rats was investigated. Exposure to 3% CO caused respiratory arrest within about 2 minutes. The plasma uric acid level of CO-treated rats increased to 157% above that of ether-treated rats. When rats were exposed to 1% or 0.8% CO, the exposure periods until the onset of respiratory arrest were prolonged, and plasma uric acid levels at respiratory arrest were further elevated. Plasma uric acid levels at respiratory arrest increased with prolongation of the exposure periods. Under our experimental conditions, hypoxanthine or xanthine was not detected in plasma of CO-treated rats. These results are discussed in relation to the hyperuricemia in hemorrhagic shock or hypoxemia: CO-induced hyperuricemia can be attributed to the stimulated degradation of adenine nucleotides under tissue anoxia, and thus could be an excellent parameter of tissue anoxia.  相似文献   
954.
955.
956.
957.
The effectiveness of a given age determination technique can better be assessed by testing the standards on unknown specimens. A test of this nature was carried out to evaluate the authors' previously published phase method for age estimation from the sternal extremity of the rib. A sample of 15 test ribs was judged by 25 physical and forensic anthropologists with varying levels of education and experience. The judges were asked to match the rib to the phase it most closely resembled by comparing it with the photographs from the original study. The results indicated that interobserver error based on experience was minimal, and nearly all of the participants averaged within one phase of the ideal. Variation appeared to be greater among the ribs than among the judges, yet no consistent association could be made between this variation and factors such as cause of death, antemortem medical history, drug or alcohol abuse, and occupation.  相似文献   
958.
p- and o-Aminomethamphetamine were synthesized as haptens to be coupled with carrier protein at the benzene ring of methamphetamine. Immunogens were prepared by the glutaraldehyde method or the MBS (N-(m-maleimidobenzoyloxy)succinimide) type cross-linking reagent method. In particular, immunization with p-aminomethamphetamine-bovine serum albumin (BSA) conjugate prepared by the glutaraldehyde method gave an anti-methamphetamine antiserum having a low cross-reactivity with methylephedrine. With the antiserum, three kinds of immunoassays for methamphetamine were established. An enzyme immunoassay (EIA) and an enzyme-linked immunosorbent assay (ELISA) were developed with alkaline phosphatase (ALP) as a label enzyme. The amount of antibody bound ALP conjugate was determined by its activity in dephosphorylating p-nitrophenyl phosphate in EIA and nicotinamide adenine dinucleotide phosphate (NADP+) in ELISA. The range of methamphetamine measurable by ELISA was 0.025-0.5 ng/well and its sensitivity was superior to that of EIA (0.3-300 ng/tube). A latex agglutination inhibition reaction test (LAIRT) was also developed for the mass screening method of urine samples. The sensitivity of this method for methamphetamine was 0.1 micrograms/ml urine.  相似文献   
959.
Changes in methemoglobin (Met-Hb) concentrations during storage of whole blood or mixtures of blood and a cryoprotectant at refrigerated or various freezing temperatures were examined using blood samples from nitrite-administered rats and from autopsy cadavers. When whole blood was stored at 3 degrees C, Met-Hb reduction was observed in blood samples from nitrite-administered rats and in the blood from a victim poisoned by a weed killer containing some oxidant. When samples were stored at -30 degrees C, Met-Hb formation by autoxidation was inevitably observed in blood samples stored as whole blood, whereas addition of a cryoprotectant to whole blood could prevent Met-Hb formation in all the blood samples. When whole blood was stored at -80 degrees C or -196 degrees C, Met-Hb concentrations were practically stable until at least 30 days regardless of the initial values except in the control rat blood samples stored at -80 degrees C which showed slight formation of Met-Hb. From the results obtained, both the storage with a cryoprotectant at -30 degrees C and that without any additions at -80 degrees C or -196 degrees C proved to be suitable for long-term storage of blood samples from autopsy cadavers for Met-Hb determination.  相似文献   
960.
The spectrophotometric method for the determination of carboxyhemoglobin (HbCO) in blood reported by Fretwurst and Meinecke was modified so as to give the same values of percentage HbCO (HbCO%) as those determined by the oxygen electrode method. Values of HbCO% of nine practical samples determined by both the oxygen electrode method and the present method were nearly identical regardless of the presence of methemoglobin (Met-Hb) in blood. The present method is suitable for forensic practice.  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