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   2603篇
  免费   44篇
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
  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
901.
902.
On the basis of actual observations we elucidated the main processes occurring in the reparation of fractures in the skull base. The specificity of reparation was shown to be conditioned by the structure of base bones and of surrounding tissues as well as by the nature of blood supply to them. Criteria are suggested for the determination if the lesions were inflicted in life time and when.  相似文献   
903.
904.
Smith IK 《Time》2001,157(4):69
  相似文献   
905.
906.
Smith IK 《Time》2001,158(10):89
  相似文献   
907.
908.
The estimation of stature from of a variety of bones is an important aspect of forensic work. In order to obtain reliable results, it is important to have comparative data obtained from the same population group as the skeletal remains. However, lack of up to date information on the population groups of Southern Europe makes the estimation of stature from bones in this area subject to possible error. In this study, the stature of 104 healthy adults from Spain was measured, and an anteroposterior teleradiograph of the right lower and the right upper limb of every subject in the study was made in order to measure the lengths of the femur, tibia, fibula, humerus, cubitus and ulna. Pearson's regression formulae were obtained for both limbs. In males, we found the femur to be the most accurate predictor of stature (R = 0.851), whereas in females best results were obtained with the tibia (R = 0.876).  相似文献   
909.
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   
910.
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   
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