全文获取类型
收费全文 | 2850篇 |
免费 | 52篇 |
专业分类
各国政治 | 126篇 |
工人农民 | 87篇 |
世界政治 | 163篇 |
外交国际关系 | 71篇 |
法律 | 2050篇 |
中国政治 | 27篇 |
政治理论 | 357篇 |
综合类 | 21篇 |
出版年
2020年 | 36篇 |
2019年 | 27篇 |
2018年 | 29篇 |
2017年 | 37篇 |
2016年 | 49篇 |
2015年 | 33篇 |
2014年 | 42篇 |
2013年 | 211篇 |
2012年 | 66篇 |
2011年 | 72篇 |
2010年 | 44篇 |
2009年 | 40篇 |
2008年 | 63篇 |
2007年 | 85篇 |
2006年 | 78篇 |
2005年 | 77篇 |
2004年 | 74篇 |
2003年 | 76篇 |
2002年 | 75篇 |
2001年 | 164篇 |
2000年 | 131篇 |
1999年 | 81篇 |
1998年 | 29篇 |
1997年 | 26篇 |
1995年 | 23篇 |
1994年 | 28篇 |
1993年 | 26篇 |
1992年 | 68篇 |
1991年 | 73篇 |
1990年 | 62篇 |
1989年 | 85篇 |
1988年 | 85篇 |
1987年 | 75篇 |
1986年 | 77篇 |
1985年 | 68篇 |
1984年 | 39篇 |
1983年 | 43篇 |
1981年 | 44篇 |
1980年 | 26篇 |
1979年 | 30篇 |
1978年 | 21篇 |
1977年 | 29篇 |
1975年 | 33篇 |
1974年 | 30篇 |
1973年 | 33篇 |
1972年 | 32篇 |
1971年 | 24篇 |
1970年 | 20篇 |
1969年 | 26篇 |
1968年 | 20篇 |
排序方式: 共有2902条查询结果,搜索用时 15 毫秒
961.
Adherence of forensic odontologists to the ABFO bite mark guidelines for suspect evidence collection
Boards and associations within forensic science have long been accepted as vehicles for the development and dissemination of protocols and recommendations for practice. Recent controversies surrounding bite mark analyses have brought the methods and practices of forensic dentists to the attention of both the courts and the media. In the mid-eighties the American Board of Forensic Odontology developed guidelines for bite mark analysis in response to unfavorable commentaries on the discipline by legal observers. The purpose of this study is to examine the adherence of board certified and noncertified forensic dentists to the guidelines for collection of evidence from bite mark suspects. A questionnaire was employed during an American Academy of Forensic Sciences meeting. Results showed that, in general, when the odontologists collected evidence they did adhere to the guidelines, although collection of salivary samples was not common. Of concern is the large number of odontologists who do not collect their own evidence from suspects. Police officers or other individuals often perform this task and therefore the guidelines must be disseminated to these groups to ensure that the maximum yield is obtained from bite mark evidence. A review of the materials used to collect evidence is also included with details of applications in forensic science. 相似文献
962.
TWGDAM validation of the AmpFlSTR Profiler Plus and AmpFlSTR COfiler STR multiplex systems using capillary electrophoresis 总被引:3,自引:0,他引:3
LaFountain MJ Schwartz MB Svete PA Walkinshaw MA Buel E 《Journal of forensic sciences》2001,46(5):1191-1198
Prior to forensic implementation, a profiling system requires validation following the recommendations presented by the Technical Working Group on DNA Analysis Methods (TWGDAM). In this work two such systems, AmpFlSTR Profiler Plus and AmpFfSTR COfiler have been validated according to the guidelines provided by TWGDAM. Profiler Plus and COfiler simultaneously amplify nine and six STR loci respectively; both also amplify a portion of the amelogenin gene. Performance of the two STR multiplex systems under conditions set forth by TWGDAM was robust and reproducible, indicating that these systems are suitable for use in forensic analysis. Additionally, specific sections of the TWGDAM validation guidelines are especially valuable in terms of familiarizing users with particular limitations of the systems prior to taking on casework. 相似文献
963.
Winecker RE Goldberger BA Tebbett IR Behnke M Eyler FD Karlix JL Wobie K Conlon M Phillips D Bertholf RL 《Journal of forensic sciences》2001,46(5):1221-1223
A method was developed for measuring cocaine and its metabolites, benzoylecgonine, ecgonine methyl ester, norcocaine, ecgonine ethyl ester, cocaethylene, and m-hydroxybenzoylecgonine, in breast milk by gas chromatography/mass spectrometry. Limits of detection for this method ranged from 2.5 to 10 ng/mL, and limits of quantitation ranged from 5 to 50 ng/mL. For each of the compounds measured by this method, linear response was demonstrated to 750 ng/mL. Breast milk was collected from 11 mothers who admitted to drug use during pregnancy and ten drug-free volunteers serving as control subjects. Cocaine was detected in six of the specimens obtained from drug-exposed subjects, and in none of the drug-free control subjects. In breast milk specimens where cocaine and one or more of its metabolites were detected, the concentration of parent compound was greater than any of the metabolites. The highest cocaine concentration found was over 12 microg/mL. Breast-fed infants of cocaine abusing mothers may be exposed to significant amounts of drug orally. 相似文献
964.
965.
966.
An electric charge device for self defense was evaluated on a volunteer. The device is safe for life and health of a healthy adult human. Moral aspects of such trials on humans are discussed. 相似文献
967.
968.
A series of screening tests showed that separation of polymerase chain reaction products and identification of D1S80 by capillary electrophoresis with the use of hydroxyethyl cellulose as the substituting screening template and double internal DNA reference is an accurate, rapid, and reliable method, fit for routine use. D1S80-allele frequencies for Caucasian population were determined in a population of 340 unrelated individuals living in the Ural region of Russia. The D1S80 genotypical frequencies in this population sample do not statistically deviate from the Hardy-Weinberg expectations. The discrimination power for this locus is 0.935. Significant deviations from the zero hypothesis of population homogeneity were detected by comparison of 4 Caucasian population samples. Differences in the frequencies of alleles 25, 30, and 31 seem to be the main cause of heterogeneity in paired comparison. 相似文献
969.
Akopov VI 《Sudebno-meditsinskaia ekspertiza》2001,44(2):33-35
Presents data on the number of unidentified corpses sent to the morgue of Bureau of Forensic Medical Expert Evaluations of the Rostov region and discusses the shortcomings in organization of medical criminalistic personality identification. Discusses some scientific problems investigated at Department of Forensic Medicine of Rostov State Medical University. 相似文献
970.
Gerasimov IV 《Sudebno-meditsinskaia ekspertiza》2001,44(4):32-34
Poisoning with methemoglobin toxins are not rare in forensic medical practice, but there is still no reliable method for measuring methemoglobin in cadaveric biological fluids and tissues. The author investigated factors affecting evaluation of natural amounts of methemoglobin in the blood, compared several methods for methemoglobin measurements, and developed qualitative characteristics indicating the presence of methemoglobin in cadaveric blood. A rational method for measuring methemoglobin in the blood, blood clots, and tissues is offered for forensic chemical and biochemical evaluations. 相似文献