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   3265篇
  免费   87篇
各国政治   168篇
工人农民   99篇
世界政治   227篇
外交国际关系   127篇
法律   2189篇
中国政治   30篇
政治理论   490篇
综合类   22篇
  2021年   27篇
  2020年   58篇
  2019年   55篇
  2018年   67篇
  2017年   75篇
  2016年   77篇
  2015年   49篇
  2014年   67篇
  2013年   293篇
  2012年   88篇
  2011年   91篇
  2010年   49篇
  2009年   51篇
  2008年   78篇
  2007年   98篇
  2006年   87篇
  2005年   94篇
  2004年   95篇
  2003年   80篇
  2002年   89篇
  2001年   161篇
  2000年   131篇
  1999年   82篇
  1998年   32篇
  1996年   24篇
  1995年   23篇
  1994年   26篇
  1993年   23篇
  1992年   65篇
  1991年   70篇
  1990年   69篇
  1989年   86篇
  1988年   84篇
  1987年   75篇
  1986年   81篇
  1985年   67篇
  1984年   40篇
  1983年   48篇
  1982年   22篇
  1981年   32篇
  1979年   31篇
  1978年   22篇
  1977年   29篇
  1976年   23篇
  1975年   34篇
  1974年   31篇
  1973年   32篇
  1972年   33篇
  1971年   27篇
  1969年   24篇
排序方式: 共有3352条查询结果,搜索用时 15 毫秒
941.
In the present study, shots from different ranges were fired using a non-choked pump-action shotgun (Hugsan) of calibre 12 with a bore length of 52cm and pellets of various sizes. The aim of the study is range estimation from the distribution of pellets.Using pellets of 2, 3.5, 5 and 8mm size, 5 shots were fired from: 0.7, 0.8, 0.9, 1, 2, 3, 5, 10, 15, 20 and 25ms. The maximum distance between the pellets in vertical and horizontal direction was measured. Statistical evaluation of the data revealed a highly significant correlation for each pellet type; the constant values a and b were calculated to be used in the linear regression equation y=a+bx.As a conclusion, the linear regression equation as well as table data may allow range determination within acceptable ranges of error for the same barrel length and diameter for the same cartridge type. Under identical conditions they may also provide information for pellets of comparable size.  相似文献   
942.

Instructions for Authors

Instructions for Authors  相似文献   
943.
Sex determination of a corpse can be problematic in cases where the body is damaged. Useful criteria would assist in the identification of sex in such cases. The goal of this study is to determine the usefulness of the external occipital protuberance (EOP) in the determination of sex, especially in lateral cranium radiographs. The types and configurations of the EOP were investigated on normal lateral cranium radiographs of 1000 subjects (500 males and 500 females) and 694 dry-skull remains (371 males and 323 females) from a 16th Century Anatolian population for the purpose of sex determination. In the radiographic examination, the incidence of less prominent (Type 1) EOP is found to be 85.4% in females whereas 17.8% in males. The spine type (Type 3) EOP is found to be 63.4% in males and to be 4.2% in females. On the other hand, studies of dry-skull remains revealed the incidence of Type 1 EOP to be 67.5% in females and Type 3 EOP to be 55.2% in males. The crest type (Type 2) EOP is approximately equal in both sexes and is found to be less valuable for sex determination in both groups.  相似文献   
944.
The human ear: its role in forensic practice   总被引:4,自引:0,他引:4  
The human ear has much to offer investigators in relation to many areas of forensic practice including forensic pathology, anthropology, identification and facial reconstruction and yet its full potential is often overlooked. This review paper explores current knowledge related to the human ear drawing attention to those situations where the ear could play a valuable role in a forensic investigation.  相似文献   
945.
946.
The risk of human immunodeficiency virus (HIV) transmission following a bite injury is important to many groups of people. The first are those who are likely to be bitten as an occupational risk, such as police officers and institutional staff. Another group are represented by the victims and perpetrators of crimes involving biting, both in attack and defense situations. The possibility of these bites transmitting a potentially fatal disease is of interest to the physicians who treat such patients and the legal system which may have to deal with the repercussions of such a transmission. Bite injuries represent 1% of all emergency department admissions in the United States, and human bites are the third most common following those of dogs and cats. The worldwide epidemic of HIV and acquired immunodeficiency syndrome (AIDS) continues, with >5 million new cases last year and affecting 1 in 100 sexually active adults. A review of the literature concerning human bites, HIV and AIDS, HIV in saliva, and case examples was performed to examine the current opinion regarding the transmission of HIV via this route. A bite from an HIV-seropositive individual that breaks the skin or is associated with a previous injury carries a risk of infection for the bitten individual.  相似文献   
947.
Stab-resistant body armour is now becoming a standard item of equipment for police officers in the United Kingdom. In the UK these are usually required to have a stab resistance as specified by the Police Scientific Development Branch KR42 standard [G. Parker, PSDB Stab Resistant Body Armour Test Procedure, Police Scientific Development Branch, Publication No 10/93, 1993]. There are several other test standards, all of which specify that body armour must resist penetration by a specific blade type delivered at a specific energy level or range of levels. However, the actual range of energy levels specified varies over almost an order of magnitude and the basis for these levels is not clearly defined. This paper describes tests to determine the energy range and characteristics of stabbing actions that might be directed against stab resistant body armour by an assailant. The energy and velocity that can be achieved in stabbing actions has been determined for a number of sample populations. Volunteers were asked to stab a target using an instrumented knife that measured the axial force and acceleration during the stabbing. The maximum energy obtained in underarm stabbing actions was 64 J whilst overarm stabbing actions could produce 115 J. The loads produced on contact with the target often approached 1000 N.  相似文献   
948.
949.
950.
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