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   11867篇
  免费   326篇
各国政治   332篇
工人农民   671篇
世界政治   650篇
外交国际关系   358篇
法律   7742篇
中国共产党   34篇
中国政治   139篇
政治理论   2126篇
综合类   141篇
  2021年   67篇
  2020年   152篇
  2019年   141篇
  2018年   297篇
  2017年   273篇
  2016年   385篇
  2015年   256篇
  2014年   234篇
  2013年   903篇
  2012年   365篇
  2011年   374篇
  2010年   227篇
  2009年   316篇
  2008年   364篇
  2007年   378篇
  2006年   361篇
  2005年   675篇
  2004年   398篇
  2003年   266篇
  2002年   252篇
  2001年   371篇
  2000年   332篇
  1999年   273篇
  1998年   160篇
  1997年   120篇
  1996年   147篇
  1995年   121篇
  1994年   134篇
  1993年   131篇
  1992年   219篇
  1991年   269篇
  1990年   239篇
  1989年   230篇
  1988年   246篇
  1987年   224篇
  1986年   243篇
  1985年   210篇
  1984年   175篇
  1983年   172篇
  1982年   106篇
  1981年   125篇
  1980年   105篇
  1979年   111篇
  1978年   101篇
  1977年   82篇
  1976年   66篇
  1975年   78篇
  1974年   83篇
  1973年   88篇
  1971年   68篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
971.
This study examines public opinion in Costa Rica and El Salvador regarding regional integration in Central America. Recent efforts at regional integration as well as the response of the governments of the above countries to those efforts are reviewed. Public opinion toward regional integration is significantly more positive but less structured in El Salvador than in Costa Rica. Differences in the international and domestic contexts help to explain the differential responses in these two countries. Likewise, contextual factors help to account for differences between Central American and European publics in attitudes toward regional integration. Charles L. Davis is associate professor of political science at the University of Kentucky. His interests are Latin American politics and comparative political behavior. Matthew J. Gabel is assistant professor of political science at the University of Kentucky. His interests are European politics and the politics of regional integration. Kenneth M. Coleman is a former professor at the University of Kentucky, the University of North Carolina-Chapel Hill, and the University of New Mexico. His interests are Latin American politics and public opinion.  相似文献   
972.
Demographic and trend analysis of 881 consecutive suicides in blacks and whites is presented. For the years 1975 through 1984, the suicide rate was 15.1/100 000 and did not significantly change. White males were overrepresented in all age groups, had an overall suicide rate of 34.9, and showed a small but statistically significant increase in rate which was not accounted for by any specific age group. White females, in general, were represented in proportion to their prevalence in the population, and those ages 20 to 24 demonstrated an increasing suicide rate which was small. Black males were at highest risk in their twenties, showed no significant trends, and were also represented near their prevalence in the population. Black females of all ages were underrepresented, and had low suicide rates which decreased with time. No significant rate changes were noted for teenagers or the elderly. Firearms was the method of choice in all groups, although methods varied with age, race, and sex, and male children preferred hanging. Small but significant increases were noted for the prevalence of nondrug methods in females and carbon monoxide deaths in white males. Similarities and differences to larger scale studies are discussed. Suicide may have characteristics unique to given geographical areas and pervasive to all areas. The authors advocate study and publication of local data to clarify further the nature of suicide.  相似文献   
973.
974.
The armamentarium of the forensic thanatologist includes the examiner's subjective assessment of bodily changes together with comprehensive evaluation of environmental and associated factors to estimate the postmortem interval (PMI). Of the various objective means, postmortem accumulation of potassium in vitreous humor is a widely used gauge. In view of the considerable variability inherent in these techniques, an additional marker with greater accuracy would be a welcome supplement to these indices. We have developed a method of estimating PMI from the level of 3-methoxytyramine (3-MT) in the dorsal putamen of the brain. The supernatant of a sample of putamen, sonicated in 6 volumes (weight/volume) of 0.1 M perchloric acid and centrifuged at 51 000 times gravity for 10 min, was analyzed for 3-MT using high-pressure liquid chromatography with electrochemical detection. The change of 3-MT in the putamen is linearly related to the PMI (range: 5.5 to 60 h), irrespective of patient age (1 to 84 years). This observation is attributable to several factors, including high substrate (dopamine) concentration, preservation of catechol-O-methyl transferase activity, and an inactivation of monoamine oxidase activity, as a result of a decrease in tissue pO2.  相似文献   
975.
For the last several centuries, most jurisdictions using capital punishment have had formal or informal rules that prohibit the execution of the mentally ill. In this article, the procedures for such exclusions in Florida are examined. The article begins by attempting to answer the question of why legislators and judges, at least nominally, have prohibited the execution of the mentally ill. Next, Florida's criteria for defining and procedures for excluding mentally ill prisoners are examined and found to be vague. We then turn attention to the ethical problems created by the statute and its implementation that face the participating psychiatrists and the profession. These problems are compounded because the physician's findings are not acted upon by politically neutral authorities and the inmate has no opportunity to challenge the findings with his own panel of experts. Finally, since any exclusion of the mentally ill from execution is temporary and the patient will be executed if he recovers, the dilemmas facing the treatment staff if the death sentence is not commuted to life imprisonment before treatment are discussed.  相似文献   
976.
冯友兰是中国近现代史上著名的哲学家和哲学史家。他从中国文化和中国社会发展方向的前提出发,比较中西文化之间的差异,形成了关于文化问题和社会发展问题的一系列观点。他所提出的以“文化类型”说、“继往开来”说和“道统新续”说为内容的“文化三说”观,对于妥善处理中西文化冲突与融合过程中的时代性和民族性的关系,以及如何弘扬中国传统文化的精华与吸收外国文化的长处等问题,仍然具有积极的现实启迪意义。  相似文献   
977.
Chloroquine concentrations in blood and tissues were examined in overdose and non-overdose cases to determine appropriate ranges for interpretation. Twenty-nine literature overdose cases and 8 non-overdose literature cases were compared with this laboratory's findings. The results indicate significant postmortem redistribution of chloroquine. Combining this laboratory's results and the literature results indicates that using a liver concentration of 150 mg/kg as a cutoff between overdose and non-overdose concentrations properly identified 30 of the 34 published cases containing liver chloroquine and 19 of the 20 presented cases.  相似文献   
978.
A simple and rapid method for the isolation of seven synthetic pyrethroid insecticides (methothrin, fenpropathrin, cyhalothrin, permethrin, cypermethrin, fenvalerate, deltamethrin) with a solid phase extraction (SPE), utilizing Sep-Pak C18 cartridges, from human urine and plasma is presented. The detection of the insecticides was performed using a wide bore capillary gas chromatograph (GC) with flame ionization detection (FID). The insecticide-containing samples mixed with 70% methanol were directly applied to the cartridges and eluted with 2 ml chloroform. The recoveries using the cartridges were between 90-102% for urine and 81-93% for plasma. Mixing samples with 70% methanol prior to extraction, seems very useful for the screening of synthetic pyrethroid insecticides.  相似文献   
979.
A technique is described for the typing of glyoxalase I (GLO I) and the subtyping of phosphoglucomutase-1 (PGM-1) from the root sheath cells of a single forcibly removed hair. This procedure does not require sample preparation and does not alter the morphological characteristics of the hair. The combined discrimination probability (DP) of the two markers taken together is 0.90 for whites and 0.89 for blacks. GLO I can be typed after four weeks, and PGM-1 can be typed after eight to fifteen weeks in hairs maintained at room temperature. Hairs mounted with Permount showed loss of enzyme activity and loss of band sharpness.  相似文献   
980.
Do we know the lethal dose of cocaine?   总被引:1,自引:0,他引:1  
  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