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   24782篇
  免费   497篇
各国政治   903篇
工人农民   1602篇
世界政治   1590篇
外交国际关系   851篇
法律   14627篇
中国共产党   2篇
中国政治   75篇
政治理论   5455篇
综合类   174篇
  2020年   210篇
  2019年   250篇
  2018年   1519篇
  2017年   1495篇
  2016年   1359篇
  2015年   341篇
  2014年   342篇
  2013年   1692篇
  2012年   574篇
  2011年   1283篇
  2010年   1280篇
  2009年   909篇
  2008年   1120篇
  2007年   1100篇
  2006年   443篇
  2005年   442篇
  2004年   551篇
  2003年   551篇
  2002年   403篇
  2001年   681篇
  2000年   623篇
  1999年   507篇
  1998年   294篇
  1997年   251篇
  1996年   221篇
  1995年   230篇
  1994年   267篇
  1993年   219篇
  1992年   340篇
  1991年   368篇
  1990年   327篇
  1989年   346篇
  1988年   320篇
  1987年   341篇
  1986年   339篇
  1985年   332篇
  1984年   301篇
  1983年   327篇
  1982年   265篇
  1981年   241篇
  1980年   179篇
  1979年   252篇
  1978年   173篇
  1977年   158篇
  1976年   137篇
  1975年   125篇
  1974年   137篇
  1973年   124篇
  1972年   115篇
  1971年   99篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
231.
This paper provides a brief biography of Luke S. May (1886-1965), whose pioneering work in forensic science in the United States has not received full recognition. May began as a private detective in Salt Lake City, Utah, shortly after the turn of the century and later established his own agency, the Revelare International Secret Service, which he moved to Seattle, Washington, in 1919. Although basically self-taught in scientific matters, May built a solid reputation among police agencies and attorneys in the Pacific Northwest and Western Canada as a serious and effective scientific investigator in the era before public crime laboratories. This reputation as "America's Sherlock Holmes" also led to his being consulted on the establishment of the first American crime laboratory at Northwestern University in Chicago, Illinois, and on a laboratory for the Royal Canadian Mounted Police at Regina, in Saskatchewan, Canada. He contributed to a landmark case of court acceptance of toolmark identification, invented specialized instruments, and founded an institute to teach scientific criminal investigation to police officers. His earliest associates were John L. Harris and J. Clark Sellers, both of whom became recognized document examiners on the West Coast and were followed by a second and a third generation of practitioners.  相似文献   
232.
233.
234.
In this article we examine how increasing the reimbursement of physicians and expanding Medicaid eligibility affect access to care for children in Cook County, Illinois, which overlies Chicago. Using Medicaid claims and other data at the zip-code level, we compare the places where Medicaid children live with the places where all the physicians who treat children and those who accept Medicaid patients have their practices. Our findings suggest that the recent changes in legislation are unlikely to benefit extremely poor children, who are more likely to live in depressed inner-city areas, where there are few physicians. "Near-poor" children whose homes are dispersed throughout the county, who are now eligible for Medicaid as a result of the recent changes, are likely to see improvements in their access to care. Further changes in policy, aimed at enhancing the capacity of institutions providing care, could improve access for the children of the inner city.  相似文献   
235.
236.
237.
We report seven fatalities resulting from the ingestion of illicit drugs packaged in condoms, rubber balloons, or plastic bags which were observed in the last 4 years at the Office of the Chief Medical Examiner, State of Maryland. All the victims, with the exception of one, were men ranging in age from 19 to 37 years. There was no racial predominance. No drug paraphernalia was found at any scene. In two cases, seizure-like activity was documented. One victim had recently returned from Nigeria; therefore, Lassa fever was initially suspected. Two of the victims were "body packer" contrabanders who had just arrived from Africa. They used body cavities to hide large amounts of heroin to avoid U.S. Customs. The other five cases were "mini-packers," small-time illicit drug dealers who had swallowed a single bag of cocaine to avoid police detection. The possible mechanism of leaking or rupture of the latex container is discussed.  相似文献   
238.
During preliminary examination of the body of a homicide victim, a peculiar red "fiber" was noticed and recovered. Initially believing this to be a carpet fiber, the item was subjected to fiber analysis. It was found to be a short coiled particle not like any known natural or synthetic fabric fiber. Subsequent examinations determined this "fiber" to be the larva of a common freshwater midge (Diptera; Chironomidae). Chironomid larvae have been observed on other bodies recovered from freshwater environments. Entomological studies of this organism have led to the conclusion that the presence of chironomid larvae indicates submersion of the body.  相似文献   
239.
240.
So far, the law in the Federal Republic of Germany still allows the injection of fresh-cell preparations from animals as a roborant to increase the vitality of the organism and to strengthen the body's immune defense system. The use of "sicca-cell" preparations was provisionally forbidden in 1987 by the Federal Health Organization (Bundesgesundheitsamt; BGA). Prohibition of fresh-cell injections would have exceeded the authority of this office, although the same serious reservations also applied in the case of this treatment method. Several publications that have appeared since 1955 have reported serious complications of this therapy, some life-threatening and some even lethal. Two further cases are now added: (1) A woman aged 69 had been receiving treatment with cell injections for 9 years. Immediately after an injection of sicca cells she collapsed and was hospitalized; 7 days thereafter she developed an ascending paralysis with increasing inability to swallow or breathe. She died 25 days after the injection as a consequence of central and peripheral respiratory failure. Autopsy revealed the alterations typical for acute Landry-Guillain-Barré-Strohl syndrome. (2) A 76-year-old healthy woman had been receiving treatment with fresh-cell preparations for several years. After an injection of cell suspensions a painful local swelling was observed. The symptoms were interpreted as the consequence of an iatrogenic local hematoma, and repeated punctures were performed to obtain blood. The patient was transferred to a surgical department for further therapy. Two days after the injection she suddenly died with signs of acute cardiovascular failure. Autopsy revealed the signs of a fulminating clostridial infection and also the characteristic signs of Landry-Guillain-Barré syndrome with involvement of the autonomic nervous system. In both cases the development of an inflammatory process in the peripheral nervous system could be interpreted as an immune-mediated allergic disease, related to the repeated injection of heterologous antigenic material containing nervous tissues. This hypothesis would also explain the two other cases already published and would be consistent with the observed perivenous leukoencephalopathy of the central nervous system. The human disease pictures correspond to the well-established animal models of EAEM (experimental allergic encephalomyelitis) and EAN (experimental allergic neuritis). The pathogenesis is discussed; the major role of the central and peripheral nervous system is stressed, with special reference to the risk of acute autonomic failure. The need for specific autopsy techniques for the investigation of the entire nervous system, including spinal cord, roots, spinal ganglia and peripheral nerves with sympathetic chains, is raised.  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