全文获取类型
收费全文 | 2606篇 |
免费 | 41篇 |
专业分类
各国政治 | 126篇 |
工人农民 | 62篇 |
世界政治 | 152篇 |
外交国际关系 | 66篇 |
法律 | 1917篇 |
中国政治 | 21篇 |
政治理论 | 286篇 |
综合类 | 17篇 |
出版年
2020年 | 30篇 |
2019年 | 22篇 |
2018年 | 22篇 |
2017年 | 33篇 |
2016年 | 40篇 |
2015年 | 23篇 |
2014年 | 38篇 |
2013年 | 187篇 |
2012年 | 60篇 |
2011年 | 68篇 |
2010年 | 36篇 |
2009年 | 35篇 |
2008年 | 56篇 |
2007年 | 71篇 |
2006年 | 71篇 |
2005年 | 74篇 |
2004年 | 72篇 |
2003年 | 70篇 |
2002年 | 70篇 |
2001年 | 156篇 |
2000年 | 123篇 |
1999年 | 76篇 |
1998年 | 26篇 |
1995年 | 18篇 |
1994年 | 22篇 |
1993年 | 21篇 |
1992年 | 63篇 |
1991年 | 69篇 |
1990年 | 61篇 |
1989年 | 84篇 |
1988年 | 83篇 |
1987年 | 72篇 |
1986年 | 76篇 |
1985年 | 65篇 |
1984年 | 35篇 |
1983年 | 41篇 |
1982年 | 19篇 |
1981年 | 30篇 |
1979年 | 28篇 |
1978年 | 21篇 |
1977年 | 27篇 |
1976年 | 19篇 |
1975年 | 31篇 |
1974年 | 30篇 |
1973年 | 31篇 |
1972年 | 32篇 |
1971年 | 24篇 |
1970年 | 20篇 |
1969年 | 24篇 |
1968年 | 20篇 |
排序方式: 共有2647条查询结果,搜索用时 15 毫秒
811.
Cocaine in Wayne County Medical Examiner's cases 总被引:1,自引:0,他引:1
We determined the incidence of detection of cocaine or its metabolites in Wayne County (Michigan) Medical Examiner's cases from 1984 to 1987. Over this four-year period there was a significant (P less than 0.01) increase each year in evidence of recent cocaine use in this population, reaching 38.3% of all tested cases in 1987. Much of this increase was accounted for by homicide victims, especially those in their third or fourth decade of life, of whom 58.6 and 56.3%, respectively, tested positive in 1987. There was a large increase in recent cocaine use in teenage homicide victims in 1987, having previously changed little from 1984 to 1986. In victims of drug abuse, recent cocaine use also increased significantly (p less than 0.01) each year, reaching 47.6% in 1987, generally in combination with heroin. Although deaths attributed solely to cocaine were not as common, they also increased significantly each year from 4 in 1984 to 25 in 1987. Compared with the general population, those who use cocaine in Wayne County are more likely than those who do not to die prematurely, often as a result of violence. 相似文献
812.
E I Deriugina N I Drize L N Lemeneva E Iu Sadovnikova G A Udalov I L Chertkov 《Sudebno-meditsinskaia ekspertiza》1990,33(1):35-37
In this article serologic characteristics of monoclonal antibodies with anti-N specificity is given. Antibodies are directed to homologous sequence of N-form of A glycophorine (group-specific N-antigen) and B glycophorine, expressed both on N- and on M-erythrocytes. Higher titre and avidity of monoclonal antibodies with anti-N specificity in relation to erythrocytes with N-phenotype make it possible to detect N-antigen in material subjected to expert evaluation. 相似文献
813.
Government supported industry-university research centers: Issues for successful technology transfer
Dr. Michael D. Devine Dr. Thomas E. James Jr. Mr. Timothy I. Adams 《The Journal of Technology Transfer》1987,12(1):27-37
In order to increase the use of federally supported research and development to increase U.S. industrial competitiveness, new partnerships are being developed among the research producers, users, and funders. This paper summarizes the evolution of federal technology transfer models with particular attention to university-industry cooperative research centers sponsored by the National Science Foundation. The advantages and potential problems associated with such centers are presented and the implications for technology and innovation are discussed. 相似文献
814.
Deliberate ingestion of a corrosive acid is an unusual manner of death. Sulfuric acid, often used in electrical industry, chemical laboratories, and agriculture, is fatal at a dosage of 3.5-7.0 ml. The mortality rate is quite high, with only 35% recovery rate. Poisoning by sulfuric acid resembles other mineral acids in that the esophagus is more commonly spared while coagulative necrosis of the stomach is often apparent. A case involving the ingestion of sulfuric acid by a patient with a history of chronic psychiatric illness is presented. The pathological, clinical, and toxicological aspects of this case are discussed. 相似文献
815.
816.
Chronic alcoholic intoxication was found to result in changes in trace elemental structure of human hair and mongrel white rat hair. Reliable increase of iron, zinc, copper and manganese in hair of alcoholic patients and tendency to increase iron content in rat hair were detected. 相似文献
817.
818.
819.
A new isoelectric focusing method is described for phenotyping of esterase D in blood stains and hair roots. It permitted easy and rapid discrimination of six phenotypes determined by ESD*1, ESD*2 and ESD*7. Experiments showed it to be practicable in forensic stain work. In addition, this technique was also usable in phenotyping of ESD 5. 相似文献
820.
M Ota I Yonemura H Fukushima H Hasekura G Ishimoto Y Mizutani T Yamada 《Journal of forensic sciences》1987,32(6):1806-1810
A paternity test is presented in which a father and his two children possessed an extremely rare amorphic gene R-29 (r,---). One of the children was determined to be illegitimate at the first trial as her Rh phenotype was R2R2(ccDEE) and the father's phenotype was R1R1(CCDee). At the Court of Appeal, however, the rare Rh gene r(---) was shown to be inherited from the father to the appellant child through extended tests including her brother whose phenotype was also R2R2(ccDEE). She was acknowledged to be legitimate. 相似文献