全文获取类型
收费全文 | 22849篇 |
免费 | 682篇 |
专业分类
各国政治 | 915篇 |
工人农民 | 868篇 |
世界政治 | 1845篇 |
外交国际关系 | 777篇 |
法律 | 14032篇 |
中国共产党 | 2篇 |
中国政治 | 119篇 |
政治理论 | 4766篇 |
综合类 | 207篇 |
出版年
2020年 | 292篇 |
2019年 | 343篇 |
2018年 | 436篇 |
2017年 | 522篇 |
2016年 | 561篇 |
2015年 | 387篇 |
2014年 | 470篇 |
2013年 | 2231篇 |
2012年 | 554篇 |
2011年 | 591篇 |
2010年 | 476篇 |
2009年 | 511篇 |
2008年 | 592篇 |
2007年 | 643篇 |
2006年 | 622篇 |
2005年 | 539篇 |
2004年 | 541篇 |
2003年 | 575篇 |
2002年 | 518篇 |
2001年 | 892篇 |
2000年 | 836篇 |
1999年 | 663篇 |
1998年 | 352篇 |
1997年 | 299篇 |
1996年 | 269篇 |
1995年 | 263篇 |
1994年 | 308篇 |
1993年 | 270篇 |
1992年 | 436篇 |
1991年 | 478篇 |
1990年 | 430篇 |
1989年 | 458篇 |
1988年 | 420篇 |
1987年 | 453篇 |
1986年 | 431篇 |
1985年 | 450篇 |
1984年 | 380篇 |
1983年 | 422篇 |
1982年 | 317篇 |
1981年 | 308篇 |
1980年 | 235篇 |
1979年 | 321篇 |
1978年 | 233篇 |
1977年 | 197篇 |
1976年 | 174篇 |
1975年 | 162篇 |
1974年 | 185篇 |
1973年 | 169篇 |
1972年 | 146篇 |
1971年 | 139篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
251.
J W Fossett J D Perloff P R Kletke J A Peterson 《Journal of health politics, policy and law》1992,17(2):273-298
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
252.
253.
254.
255.
256.
The "mini-packer" syndrome. Fatal ingestion of drug containers in Baltimore, Maryland 总被引:1,自引:0,他引:1
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
257.
D A Hawley N H Haskell D G McShaffrey R E Williams J E Pless 《Journal of forensic sciences》1989,34(3):617-621
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
258.
259.
260.
Programme based on mathematical model of the process of dead body temperature changing was developed for estimation of postmortem interval. Automatic retrieval of problem solution was performed on programmable microcalculators of "Electronica MK-61" type using adaptive approach. Diagnostical accuracy in case of dead body being preserved in permanent cooling conditions is +/- 3%. 相似文献