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   751篇
  免费   34篇
各国政治   52篇
工人农民   61篇
世界政治   50篇
外交国际关系   28篇
法律   376篇
中国政治   4篇
政治理论   208篇
综合类   6篇
  2023年   6篇
  2020年   9篇
  2019年   26篇
  2018年   28篇
  2017年   22篇
  2016年   19篇
  2015年   21篇
  2014年   26篇
  2013年   99篇
  2012年   19篇
  2011年   23篇
  2010年   18篇
  2009年   26篇
  2008年   28篇
  2007年   27篇
  2006年   24篇
  2005年   24篇
  2004年   29篇
  2003年   13篇
  2002年   17篇
  2001年   21篇
  2000年   14篇
  1999年   15篇
  1998年   6篇
  1997年   11篇
  1996年   13篇
  1995年   5篇
  1994年   13篇
  1993年   15篇
  1992年   9篇
  1991年   16篇
  1990年   13篇
  1989年   9篇
  1988年   15篇
  1987年   4篇
  1986年   12篇
  1985年   12篇
  1984年   12篇
  1983年   9篇
  1982年   4篇
  1981年   6篇
  1980年   5篇
  1979年   7篇
  1978年   3篇
  1977年   5篇
  1976年   3篇
  1974年   3篇
  1973年   3篇
  1965年   2篇
  1964年   3篇
排序方式: 共有785条查询结果,搜索用时 15 毫秒
111.
Epidemiologic research often relies on existing data, collected for nonepidemiologic reasons, to support studies. Data are obtained from hospital records, police reports, labor reports, death certificates, or other sources. Medical examiner/coroner records are, however, not often used in epidemiologic studies. The National Institute for Occupational Safety and Health's Division of Safety Research has begun using these records in its research program on work-related trauma. Because medical examiners and coroners have the legal authority and responsibility to investigate all externally caused deaths, these records can be used in surveillance of these deaths. Another use of these records is to validate cases identified by other case ascertainment methods, such as death certificates. Using medical examiner/coroner records also allows rapid identification of work-related deaths without waiting several years for mortality data from state offices of vital statistics. Finally, the records are an invaluable data source since they contain detailed information on the nature of the injury, external cause of death, and results of toxicologic testing, which is often not available from other sources. This paper illustrates some of the ways that medical examiner/coroner records are a valuable source of information for epidemiologic studies and makes recommendations to improve their usefulness.  相似文献   
112.
113.
More than half the poor are not covered by Medicaid, the program designed to serve them. Louise Russell outlines a program that would make health care available to all of the poor.  相似文献   
114.
115.
116.
117.
Treatments for wife assaulters and their victims have been based on a variety of psychological and sociological theories. Tests of theory based on investigation of assailant and victim characteristics as well as evaluation of treatment effects based on empirical outcome studies have yielded diverse results. In reviewing the literature it appears that development of assailant typologies based on extent of psychopathology, severity of violence, and context of violence has potential utility in guiding future treatment decisions for assaulters. Further development of similar typologies for classifying responses of assaulted women could yield similar results. Population screening and matching programs to individual characteristics could be expected to improve clinical outcomes.  相似文献   
118.
The routine production of a cast of a shoe-print taken in soil provides information other than shoe size and gait. Material adhering to the surface of the cast represents the preservation of the moment of footprint impression. The analysis of the interface between the cast and soil is therefore a potentially lucrative source of information for forensic reconstruction. These principles are demonstrated with reference to a murder case which took place in the English Midlands. The cast of a footprint provided evidence of a two-way transfer of material between the sole of a boot and the soil of a recently ploughed field. Lumps of soil, which had dried on a boot, were deposited on the field as the footprints were made. Pollen analysis of these lumps of soil indicated that the perpetrator of the imprint had been standing recently in a nearby stream. Fibre analysis together with physical and chemical characteristics of the soil suggested a provenance for contamination of this mud prior to deposition of the footprint. Carbon/nitrogen ratios of the water taken from the cast showed that distilled water had been used thus excluding the possibility of contamination of the boot-soil interface. It was possible to reconstruct three phases of previous activity of the wearer of the boot prior to leaving the footprint in the field after the murder had taken place. This analysis shows the power of integrating different independent techniques in the analysis of hitherto unrecognised forensic materials.  相似文献   
119.
120.
Quartz sand surface texture analysis has been automated for the first time for forensic application. The derived Basic Image Features (BIFs) provide computer-generated texture recognition from preexisting data sets. The technique was applied to two distinct classification problems; first, the ability of the system to discriminate between (quartz) sand grains with upturned plate features (indicative of eolian, global sand sea environments) and grains that do not exhibit these features. A success rate of grain classification of 98.8% was achieved. Second, to test the ability of the computer recognition system to identify specific energy levels of formation of the upturned plate surface texture features. Such recognition ability has to date been beyond manual geological interpretation. The discrimination performance was enhanced to an exact classification success rate of 81%. The enhanced potential for routine forensic investigation of the provenance of common quartz sand is indicated.  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