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   23773篇
  免费   1377篇
各国政治   1072篇
工人农民   1116篇
世界政治   1578篇
外交国际关系   836篇
法律   16088篇
中国共产党   2篇
中国政治   137篇
政治理论   4200篇
综合类   121篇
  2023年   120篇
  2021年   135篇
  2020年   518篇
  2019年   568篇
  2018年   746篇
  2017年   777篇
  2016年   863篇
  2015年   626篇
  2014年   678篇
  2013年   2524篇
  2012年   695篇
  2011年   731篇
  2010年   683篇
  2009年   733篇
  2008年   699篇
  2007年   706篇
  2006年   689篇
  2005年   576篇
  2004年   587篇
  2003年   510篇
  2002年   537篇
  2001年   870篇
  2000年   800篇
  1999年   647篇
  1998年   307篇
  1997年   241篇
  1996年   262篇
  1995年   249篇
  1994年   239篇
  1993年   230篇
  1992年   414篇
  1991年   416篇
  1990年   426篇
  1989年   407篇
  1988年   439篇
  1987年   377篇
  1986年   421篇
  1985年   427篇
  1984年   335篇
  1983年   303篇
  1982年   235篇
  1981年   204篇
  1980年   187篇
  1979年   280篇
  1978年   163篇
  1977年   128篇
  1976年   110篇
  1975年   128篇
  1974年   165篇
  1973年   112篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
Offender assessment and classification is becoming an increasingly important part of correctional supervision and intervention. Over the last several decades, several different methods and “generations” of offender classification have emerged. Of most value appear to be third-generation, actuarial, dynamic risk/need assessments. With any new correctional strategy, however, there is a need to investigate the use of these risk/need assessments on offender subgroups in order to inform issues, such as reliability and prevalence of criminogenic risk factors. The present study utilized data that were gathered using the Level of Service Inventory-Revised (LSI-R). Results and comparisons of these assessments were investigated and presented for Native American and non-Native American offenders as well as male and female offenders. Discussion of the results, implications, and recommendations for further research are presented.  相似文献   
74.
75.
76.
What Do Prosecutors Maximize? Evidence from the Careers of U.S. Attorneys   总被引:1,自引:0,他引:1  
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 prosecutors’maximizing 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   
77.
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   
78.
79.
A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53-73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI/Pvu II, and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 +/- 7.2%. An example for the application of MZ 1.3 to paternity testing in an incest case is given. The probe can be used with radioactive or non-radioactive detection systems. An approach is presented to compare polymorphic fragment patterns from individuals obtained by independent gel runs on the basis of relative band positions (RBP) and calculated in a computerized analysis.  相似文献   
80.
Good gas chromatography (GC) separation of molecules is essential for clean gas chromatography/mass spectrometry (GC/MS) confirmation of compounds. The trifluoro derivatives of ephedrine (E) and methamphetamine (MA) coelute on dimethyl silicone capillary columns, such as DB-1, which are most commonly used by chromatographers. Methods are described to separate E and MA to aid GC/MS confirmations of methamphetamine, ephedrine, or both E and MA together, whichever may be present in Enzyme Immunoassay (EIA)-analyzed amphetamine-positive urine samples. The use of the heptafluoro derivatives of E and MA on a DB-1 column, or the trifluoro derivatives of E and MA on a DB-17 column, is suggested for good gas chromatographic separation.  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