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   1347篇
  免费   27篇
各国政治   74篇
工人农民   47篇
世界政治   86篇
外交国际关系   29篇
法律   907篇
中国政治   28篇
政治理论   196篇
综合类   7篇
  2021年   14篇
  2020年   18篇
  2019年   25篇
  2018年   24篇
  2017年   23篇
  2016年   33篇
  2015年   19篇
  2014年   18篇
  2013年   94篇
  2012年   37篇
  2011年   33篇
  2010年   32篇
  2009年   22篇
  2008年   42篇
  2007年   25篇
  2006年   23篇
  2005年   36篇
  2004年   47篇
  2003年   43篇
  2002年   31篇
  2001年   101篇
  2000年   68篇
  1999年   79篇
  1998年   40篇
  1997年   9篇
  1996年   7篇
  1995年   14篇
  1994年   7篇
  1993年   10篇
  1992年   26篇
  1991年   25篇
  1990年   41篇
  1989年   32篇
  1988年   37篇
  1987年   28篇
  1986年   19篇
  1985年   16篇
  1984年   11篇
  1983年   11篇
  1982年   16篇
  1981年   11篇
  1980年   7篇
  1979年   15篇
  1978年   9篇
  1976年   8篇
  1974年   7篇
  1973年   6篇
  1971年   10篇
  1970年   7篇
  1968年   6篇
排序方式: 共有1374条查询结果,搜索用时 15 毫秒
91.
A new method for diatom detection is described. It includes an ultrasonic irradiation procedure with the use of a tissue solubilizer. The method is easy to carry out and is less time-consuming than previous techniques.  相似文献   
92.
Methamphetamine in urine samples from abusers was detected by the latex agglutination inhibition reaction test with latex-antibody (Latex-Ab) and latex-methamphetamine (Latex-MA) reagents. Anti-methamphetamine antibody was produced in rabbits by immunization with bovine serum albumin (BSA)-methamphetamine conjugate. Latex particles were coated with antibodies or with rabbit serum albumin (RSA)-methamphetamine conjugate to obtain Latex-Ab and Latex-MA reagents, respectively. The results are read at 4-5 min after mixing the latex reagents. The sensitivity of this method for methamphetamine was 0.4 micrograms/ml urine. Methamphetamine analogs (methylephedrine, amphetamine, phentermine, methoxyphenamine, ephedrine, beta-phenylethylamine, OH-methamphetamine, OH-amphetamine, and OH-ephedrine) all cross-react in varying degrees, while glucosiurea and albuminurea give false positive results in the tests. Though attention must be paid to these effects this simple and rapid test is suitable for the mass screening of urine samples.  相似文献   
93.
94.
95.
96.
97.
98.
In this study, we analyzed allelic sequences of 10 novel Y-specific STR loci, DYS454, DYS510, DYS513, DYS520, DYS542, DYS544, DYS552, DYS561, DYS587 and DYS593, surveyed the distribution of haplotypes in a Chinese Han population. Extracted DNA was amplified with PCR, followed by a horizontal non-denaturing polyacrylamide gel electrophoresis with discontinuous buffer system. Purified alleles were sequenced on DNA sequencer (ABI Model 377) to verify the number of motif repeats. The number of alleles observed at each locus ranged from 3 to 8, yielding 102 haplotypes in 103 unrelated males samples. The allele diversity values for each locus ranged from 0.2099 (DYS544) to 0.7523 (DYS552). The haplotype diversity using all these loci was 0.9998. Our study revealed that they were valuable Y-specific markers for forensic applications.  相似文献   
99.
A criminal case was directed to a multidisciplinary forensic team for identification, concerning a victim whose head, having two gunshot wounds, had been separated by a sharp instrument and was recovered 6 months later. The purpose of this research was to determine the sex and age of the victim for human identification. Primarily, macroscopic examination of the skull, tooth, and DNA analysis was conducted for sex determination. A rough assessment of age was made from the skull based on anthropological findings, however a more definitive result of age estimation was determined utilizing dental morphology. The dental data showed an age range of 32-37 from the mineral examination and the formulation of microscopic measurements. The results obtained from the skull and dental analysis matched with the physical characteristics of the victim's body, the known personal data of this person, and with the superposition of the photos gathered by a formal request. Besides, the result of DNA profiling of the victim showed male gender and direct relationship with the victim's presumed wife and daughter. Generally, research on human identification consists of sex and age determination. The sex characteristics can be precisely proved from DNA tests. However, age can be estimated by skeletal, and dental analysis. In this case the performed sex and age analysis lead the research to the selective matching of the missing person's identity.  相似文献   
100.
Using the traditional scenario of tort conflict as an example, I argue that the marginal precautionary costs of injurers and victims are not constant, as was assumed by most previous researchers. The precedent of a liability rule has some natural externality on the precaution technology, and hence marginal cost, faced by future agents involved in torts. The adoption of legal rules therefore has a network effect, meaning that the present prevalent adoption of one rule increases the probability of its future adoption. Treating the dynamic evolution of legal rules as a random process, we are able to apply an established result in the literature of network economies to conclude the path-dependence, non-predictability, and potential inefficiency concerning the final legal rule to which the dynamics converge.  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