全文获取类型
收费全文 | 7128篇 |
免费 | 214篇 |
专业分类
各国政治 | 251篇 |
工人农民 | 400篇 |
世界政治 | 412篇 |
外交国际关系 | 311篇 |
法律 | 4623篇 |
中国政治 | 35篇 |
政治理论 | 1282篇 |
综合类 | 28篇 |
出版年
2023年 | 49篇 |
2021年 | 44篇 |
2020年 | 94篇 |
2019年 | 119篇 |
2018年 | 245篇 |
2017年 | 185篇 |
2016年 | 277篇 |
2015年 | 127篇 |
2014年 | 150篇 |
2013年 | 606篇 |
2012年 | 279篇 |
2011年 | 258篇 |
2010年 | 145篇 |
2009年 | 191篇 |
2008年 | 170篇 |
2007年 | 164篇 |
2006年 | 162篇 |
2005年 | 490篇 |
2004年 | 228篇 |
2003年 | 154篇 |
2002年 | 122篇 |
2001年 | 240篇 |
2000年 | 224篇 |
1999年 | 167篇 |
1998年 | 71篇 |
1997年 | 75篇 |
1996年 | 63篇 |
1995年 | 57篇 |
1994年 | 60篇 |
1993年 | 57篇 |
1992年 | 139篇 |
1991年 | 125篇 |
1990年 | 153篇 |
1989年 | 160篇 |
1988年 | 157篇 |
1987年 | 154篇 |
1986年 | 127篇 |
1985年 | 125篇 |
1984年 | 92篇 |
1983年 | 83篇 |
1982年 | 56篇 |
1981年 | 48篇 |
1980年 | 43篇 |
1979年 | 58篇 |
1978年 | 47篇 |
1975年 | 42篇 |
1974年 | 63篇 |
1973年 | 41篇 |
1971年 | 41篇 |
1970年 | 41篇 |
排序方式: 共有7342条查询结果,搜索用时 15 毫秒
21.
22.
This study examines the performance of chief federal prosecutors(U.S. attorneys) and their subsequent careers. In a sample of570 attorneys in office from 1969 to 2000, the length of prisonsentences is positively related to subsequent favorable careeroutcomes for U.S. attorneys. In contrast, conviction rates donot appear to affect the careers of U.S. attorneys. These resultsare consistent with longer total prison sentences beingpersonally beneficial to prosecutors, and prosecutorsmaximizing the length of prison sentences. Overall, the resultssuggest that sentence length, as opposed to convictions rates,is the relevant performance metric. 相似文献
23.
D.S.T Lo T.C Chao S.E Ng-Ong Y.J Yao T.H Koh 《Forensic Science International Supplement Series》1997,90(3):626
Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%). 相似文献
24.
25.
The enzyme activity of phosphoglucomutase (PGM) has been investigated in red cell haemolysates from 142 individuals and compared to the sub-type as determined by isoelectric focusing. The 10 phenotypes showed significant differences in PGM-activity which indicates that there is a correlation between the level of activity and the isolelectric point of homozygotes. No indication of silent alleles or alleles with reduced activity was found in this collective. 相似文献
26.
W D Haglund D G Reichert D T Reay 《The American journal of forensic medicine and pathology》1990,11(1):35-43
The Green River Murder Investigation in King County, Washington, is currently the longest active serial murder investigation in U.S. history. During its course, over 26 separate scenes with from one to five victims each have been processed. The experience of the authors is presented in order to acquaint other agencies with techniques of outdoor scene processing that have evolved during recovery of remains from Green River and other skeletal cases. 相似文献
27.
28.
J W Eisele J Frisino W Haglund D T Reay 《The American journal of forensic medicine and pathology》1987,8(3):208-209
The population-adjusted rate of teenage suicide in King County, Washington, was reviewed for the 26 years from 1959 to 1984. For the entire period, the rate did not change significantly. An abrupt change did occur during the middle of this period, but, for reasons discussed in the text, this may well represent a change in procedures and philosophy of death certification rather than a real change in rate. Reasons for the apparent discrepancy with national statistics are discussed. 相似文献
29.
Samuel T. Karnick Author Vitae 《Orbis》2007,51(1):174-187
30.
In the wake of the 1990 amendments to the Clean Air Act, localities across the United States initiated public information campaigns both to raise awareness of threats to air quality and to change behavior related to air pollution by recommending specific behavioral changes in the campaign messages. These campaigns are designed to reduce the health hazards associated with poor air quality and to avoid federal sanctions resulting from the failure to meet air quality standards. As in many other communities across the country, a coalition of government agencies and businesses initiated a public information campaign in the Atlanta metropolitan region to reduce certain targeted behaviors, mainly driving. A two‐stage model used to analyze data from a rolling sample survey shows that the centerpiece of the information campaign—air quality alerts—was effective in raising awareness and reducing driving in a segment of the population. When the overall information campaign was moderated by employers' participation in programs to improve air quality, drivers significantly reduced the number of miles they drove and the number of trips they took by car on days when air quality alerts were sounded. Public information campaigns can be successful in increasing awareness, but changing well‐established behaviors, such as driving, is likely to require institutional mediation to provide social contexts that support the behavioral change, as well. © 2003 by the Association for Public Policy Analysis and Management. 相似文献