全文获取类型
收费全文 | 3428篇 |
免费 | 56篇 |
专业分类
各国政治 | 97篇 |
工人农民 | 93篇 |
世界政治 | 145篇 |
外交国际关系 | 95篇 |
法律 | 2649篇 |
中国政治 | 17篇 |
政治理论 | 351篇 |
综合类 | 37篇 |
出版年
2020年 | 33篇 |
2019年 | 34篇 |
2018年 | 54篇 |
2017年 | 42篇 |
2016年 | 63篇 |
2015年 | 28篇 |
2014年 | 51篇 |
2013年 | 245篇 |
2012年 | 86篇 |
2011年 | 132篇 |
2010年 | 79篇 |
2009年 | 61篇 |
2008年 | 108篇 |
2007年 | 121篇 |
2006年 | 106篇 |
2005年 | 84篇 |
2004年 | 121篇 |
2003年 | 113篇 |
2002年 | 108篇 |
2001年 | 150篇 |
2000年 | 134篇 |
1999年 | 103篇 |
1998年 | 20篇 |
1995年 | 17篇 |
1993年 | 27篇 |
1992年 | 62篇 |
1991年 | 83篇 |
1990年 | 85篇 |
1989年 | 91篇 |
1988年 | 95篇 |
1987年 | 89篇 |
1986年 | 75篇 |
1985年 | 77篇 |
1984年 | 67篇 |
1983年 | 58篇 |
1982年 | 24篇 |
1981年 | 20篇 |
1979年 | 30篇 |
1978年 | 33篇 |
1977年 | 22篇 |
1976年 | 27篇 |
1975年 | 28篇 |
1974年 | 37篇 |
1973年 | 37篇 |
1972年 | 35篇 |
1971年 | 36篇 |
1970年 | 38篇 |
1969年 | 32篇 |
1968年 | 27篇 |
1967年 | 18篇 |
排序方式: 共有3484条查询结果,搜索用时 15 毫秒
911.
Stephens BG Jentzen JM Karch S Wetli CV Mash DC 《The American journal of forensic medicine and pathology》2004,25(1):11-13
The National Association of Medical Examiners Committee on Cocaine-related Deaths recommends that the following guidelines be applied in the process of documenting, interpreting, and certifying potential cocaine-related fatalities. The committee cautions that the investigation of any drug-related death requires a complete investigation of the circumstances of death, the death scene, and past medical history. It is also necessary to have the results of the forensic toxicological analysis and those of a complete forensic autopsy examination prior to formulating an opinion as to the cause and manner of death. Cocaine should be considered the underlying cause of the death when 1 or more of the following is true: (1). the circumstances surrounding the death can be associated with an acute cocaine exposure and there are no supervening causes of death; (2). the immediate cause of death is directly due to a readily identifiable mechanism or disease such as a gunshot wound or a stroke, yet the acute use of cocaine was the direct underlying cause of the trauma or the disease process; and (3). chronic cocaine use leads to a disease that results in an ultimately fatal pathologic process leading to organ injury and death. The committee further cautions that reported drug levels may not directly relate to the toxic or lethal effects of the drug upon the patient. These guidelines are intended for use by practicing medical examiners and physicians who certify drug deaths, as well as providing education tools for students. 相似文献
912.
913.
Gunshot wounds of skin and long cortical bones inflicted by the special intelligence knife (NRS and NRS-2: special silent cartridges SP-3 and SP-4) from different distances were examined. Stereomicroscopy, emission spectral analysis, contact-diffusion method and regression- step-by-step analysis were made use of within the case study. A lack of mechanical, thermal or chemical impact from firing gas and of fire soot as well as presence of particles of rubber, copper and sealing varnish, i.e. the most informative shot products, were found to be the main distinctive features in the said wounds. The data obtained can be used in the differential diagnosis of a type and model of the used gun. 相似文献
914.
Denisova VV 《Sudebno-meditsinskaia ekspertiza》2004,47(6):36
The subject of the case study was blood of 8 fish species. It was examined within the ABO system. 68 tests of stains of fish blood mixed with human blood were made. It was shown as possible to differentiate between human blood and fish blood in mixed stains. 相似文献
915.
Issues related with the material-and-technical outfit of state forensic medical bureaus of Russia's defense ministry are under discussion. The present-day condition of their instrumentation degree is described; methods are suggested of how to build up the material-and-technical base by using the limiting form system with the "conclusive medicine" principles. 相似文献
916.
A comprehensive series of experiments was undertaken to find the reasons why the cigar-butt stuff, removed from accident places for investigation at forensic-biological laboratories, affects different sera. A number of such reasons were established. Methods are suggested to eliminate the cigar-butt impact with the aim of ensuring the most accurate results while determining the group adherence of saliva on the cigar-butts. 相似文献
917.
918.
Previously, we have developed different variants, for the expert use, of information technologies, i.e. of computer automated analytical systems, to ensure an effective analysis of huge bulwarks of molecular-genetic expert findings. The results obtained in the above research significantly advanced the possibilities of expert evaluation related with personality identification under the conditions of a big death toll; they also cleaned the ground for the introduction of such methodological approaches in the practice of investigations of emergency accidents involving huge death tolls. Described within the present case study is a practical experience of forensic medical identification of unrecognized remains in air crashes with huge human death tolls implemented through computer-assisted complex molecular-genetic tests on the basis of indirect DNA identification involving the establishment of blood relationship. 相似文献
919.
920.
Yegles M Labarthe A Auwärter V Hartwig S Vater H Wennig R Pragst F 《Forensic science international》2004,145(2-3):167-173
In previous investigations hair analysis for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) proved to be suitable for the detection of excessive alcohol consumption. The aim of this study was to compare EtG and FAEE concentrations in hair of alcoholics, social drinkers and teetotallers. Hair samples from 10 alcoholics in withdrawal treatment, 11 fatalities with documented excessive alcohol consumption, four moderate social drinkers who consumed up to 20 g ethanol per day, and three strict teetotallers were analysed. After external degreasing with n-heptane, extraction with a dimethyl sulfoxide/n-heptane mixture and headspace solid-phase microextraction of the extracts, four fatty acid ethyl esters (FAEEs) (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) were analysed by gas chromatography-mass spectrometry (GC-MS) with deuterated internal standards. EtG was determined by GC-MS/NCI after ultrasonication of the samples with H2O, cleanup by SPE with aminopropyl columns and PFP derivatisation. The following concentrations were measured for the four groups: teetotallers EtG < 0.002 ng/mg, FAEE 0.05-0.37 ng/mg, moderate social drinkers EtG < 0.002 ng/mg, FAEE 0.26-0.50 ng/mg, alcoholic patients EtG 0.030-0.415 ng/mg, FAEE 0.65-20.50 ng/mg and the fatalities with alcohol history EtG 0.072-3.380 ng/mg, FAEE 1.30-30.60 ng/mg. The results confirm that by using a cut-off value of the sum of FAEE > 1 ng/mg and/or a positive EtG result in hair, excessive alcohol consumption can be identified using hair analysis. However, no significant correlation between the EtG and FAEE concentrations in the positive cases could be shown. Segmental analysis of some of the specimens did not reveal the same distribution for EtG compared to FAEE in hair, and no chronological accordance compared to the self-reported alcohol consumption could be observed for both parameters. These different results of both methods are discussed in terms of differences between EtG and FAEE in mechanism of formation and incorporation into hair and elimination from hair. 相似文献