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   19157篇
  免费   1281篇
各国政治   885篇
工人农民   913篇
世界政治   1367篇
外交国际关系   689篇
法律   12879篇
中国共产党   2篇
中国政治   128篇
政治理论   3473篇
综合类   102篇
  2023年   83篇
  2021年   93篇
  2020年   449篇
  2019年   474篇
  2018年   603篇
  2017年   634篇
  2016年   713篇
  2015年   542篇
  2014年   584篇
  2013年   2129篇
  2012年   520篇
  2011年   557篇
  2010年   579篇
  2009年   617篇
  2008年   562篇
  2007年   559篇
  2006年   572篇
  2005年   478篇
  2004年   512篇
  2003年   407篇
  2002年   455篇
  2001年   708篇
  2000年   647篇
  1999年   511篇
  1998年   280篇
  1997年   212篇
  1996年   217篇
  1995年   225篇
  1994年   204篇
  1993年   222篇
  1992年   330篇
  1991年   332篇
  1990年   319篇
  1989年   300篇
  1988年   327篇
  1987年   287篇
  1986年   339篇
  1985年   337篇
  1984年   269篇
  1983年   239篇
  1982年   185篇
  1981年   169篇
  1980年   160篇
  1979年   230篇
  1978年   119篇
  1977年   100篇
  1976年   82篇
  1975年   97篇
  1974年   128篇
  1973年   87篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
61.
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   
62.
63.
64.
65.
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   
66.
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   
67.
One case of the erroneous administration of deslanoside and high level of drug in antemortem plasma and postmortem specimens has been reported owing to the unusual surrounding circumstances. Deslanoside in antemortem plasma was determined by FPIA and the analysis was done by HPLC in the postmortem tissue samples. The analytical results and methods used in the examinations are discussed in the following paper.  相似文献   
68.
69.
Bloodstains were made with 200 microliters blood on each of 11 different common substrates to examine the effect of the stain carrier on the amount and quality of DNA recoverable. High-molecular-weight DNA was extracted from all samples after 2 days. The yield of DNA from each sample varied considerably, not only between the different stain carriers but also within a given category. With a DNA yield of up to 10 micrograms, paper, glass, nylon, wood, smooth leather and wool gave the best results, followed by blue denim and wallpaper (up to 6 micrograms), cotton fabric and carpeting (up to 4 micrograms) and suede (up to 2 micrograms). For several stain carriers the DNA-containing solution was contaminated by chemical substances, which in the case of the blue denim, suede, and carpet samples inhibited the digestion of the DNA with restriction enzymes and prevented DNA typing. The different textures of the stain carriers tested and (as for varying yields on the same carrier) the differing degree of loss of DNA during extraction and the physiological variation in the number of leukocytes in human blood are discussed as possible reasons for the wide range of variation in the amounts of DNA it was possible to extract.  相似文献   
70.
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