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   641篇
  免费   17篇
各国政治   38篇
工人农民   27篇
世界政治   16篇
外交国际关系   18篇
法律   467篇
中国政治   13篇
政治理论   77篇
综合类   2篇
  2024年   38篇
  2023年   151篇
  2022年   2篇
  2021年   37篇
  2020年   7篇
  2019年   3篇
  2018年   15篇
  2017年   10篇
  2016年   14篇
  2015年   9篇
  2014年   8篇
  2013年   59篇
  2012年   15篇
  2011年   22篇
  2010年   22篇
  2009年   23篇
  2008年   19篇
  2007年   32篇
  2006年   13篇
  2005年   10篇
  2004年   17篇
  2003年   4篇
  2002年   6篇
  2001年   5篇
  2000年   10篇
  1999年   10篇
  1998年   6篇
  1997年   5篇
  1996年   6篇
  1995年   4篇
  1994年   9篇
  1993年   5篇
  1992年   8篇
  1991年   9篇
  1990年   4篇
  1989年   5篇
  1988年   4篇
  1987年   5篇
  1986年   5篇
  1984年   4篇
  1983年   2篇
  1982年   4篇
  1981年   2篇
  1976年   2篇
  1975年   1篇
  1973年   1篇
  1971年   1篇
  1970年   1篇
  1968年   1篇
  1956年   1篇
排序方式: 共有658条查询结果,搜索用时 31 毫秒
51.
52.
The use of pyrolysis mass spectrometry (Py-MS) and statistical analysis of mass spectra is introduced as a method for “finger-printing” strains of Streptococcus salivarius. The objective is to provide correlative evidence regarding the identity of suspects in cases of assault or rape involving bite-marks. The results of the analysis of isolates from two individuals are presented, illustrating the differentiation of S. salivarius at strain level according to the origin of the isolate.  相似文献   
53.
54.
55.
Sex determination is a key analysis that forensic anthropologists perform in order to construct a biological profile of human remains. The techniques used in forensic investigations must meet the Mohan or Daubert criteria, for admissibility in a court of law. In this study, the precision and accuracy of 21 morphological characteristics of the skull were tested on a modern sample of 50 adult crania of European White ancestry. The following craniofacial features are identified as high-quality traits, defined by intraobserver error or=80%: mastoid size, supraorbital ridge size, general size and architecture, rugosity of the zygomatic extension, size and shape of the nasal aperture, and gonial angle. Ninety-six percent accuracy and 92% precision were achieved using 20 traits in combination. Fisher's exact probability tests revealed no significant differences (p=0.05) in the levels of precision or accuracy between age categories. Sex-related bias in accuracy was found for the following cranial features: ramus symphysis (p=0.009), zygomatic extension (p=0.0016), and occipital markings (p=0.0013). These traits demonstrated a greater tendency to be scored male than female.  相似文献   
56.
The formation and initial efforts of the Academy of Criminal Justice Sciences Accreditation and Standards Committee are described. The rationale for the accreditation guidelines adopted by the Academy is explained. Further efforts of the Committee to achieve the goal of the designation of the Academy as the accreditation agency for postsecondary criminal justice education programs are set forth.  相似文献   
57.
This paper examines the role that basic research plays in the strategies pursued by industry in their interactions with federal labs. It draws on questionnaire-based data of 229 federal laboratory-industry joint R&D projects with 219 companies and 27 laboratories. The study documents the relative importance of basic research in the success of the interactions by comparing the incidence of basic research on several indicators of success. The study shows that, even though projects involving basic research tend to have higher costs, they also have a high percentage of product outputs in the short term. Typical high payoff strategies for partnership were those in which the company performed several technical roles and the federal laboratory was more narrowly focused. The authors gratefully acknowledge the support of the National Science Foundation, Research on Science and Technology Program, Contract No. 9220125. The views expressed here are the authors' and do not necessarily reflect those of the National Science Foundation or any other institution.  相似文献   
58.
59.
劳动力市场人才资源的配置问题是小城镇服务业发展中急需解决的重要问题之一。本文从用人单位满意度分析的基础上,采用模糊综合评价法对当前小城镇服务业劳动力需求与人才培养对接问题现状进行了评价,发现劳动力市场人才资源的配置与人才培养供给之间出现了严重的失衡。人才培养只有遵循劳动力市场需求,动态地调整培训方案与体系,才能够健康持续地发展。  相似文献   
60.
Let’s suppose we were in the early Twentieth Century,trying to answer the question:What will be the most important things that will happen in this century?You may think about the"rise of the United States,"or the long-lived British Empire.  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