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   205篇
  免费   16篇
各国政治   24篇
工人农民   11篇
世界政治   15篇
外交国际关系   8篇
法律   141篇
政治理论   22篇
  2023年   3篇
  2021年   4篇
  2020年   7篇
  2019年   6篇
  2018年   11篇
  2017年   18篇
  2016年   12篇
  2015年   11篇
  2014年   11篇
  2013年   22篇
  2012年   12篇
  2011年   13篇
  2010年   3篇
  2009年   3篇
  2008年   5篇
  2007年   9篇
  2006年   8篇
  2005年   12篇
  2004年   13篇
  2003年   15篇
  2002年   12篇
  2000年   1篇
  1999年   1篇
  1997年   2篇
  1994年   1篇
  1993年   1篇
  1991年   2篇
  1990年   1篇
  1984年   1篇
  1978年   1篇
排序方式: 共有221条查询结果,搜索用时 15 毫秒
131.
We report on the mitochondrial DNA (mtDNA) analysis of the supposed remains of Francesco Petrarca exhumed in November 2003, from the S. Maria Assunta church, in Arquà Padua (Italy) where he died in 1374. The optimal preservation of the remains allowed the retrieval of sufficient mtDNA for genetic analysis. DNA was extracted from a rib and a tooth and mtDNA sequences were determined in multiple clones using the strictest criteria currently available for validation of ancient DNA sequences, including independent replication. MtDNA sequences from the tooth and rib were not identical, suggesting that they belonged to different individuals. Indeed, molecular gender determination showed that the postcranial remains belonged to a male while the skull belonged to a female. Historical records indicated that the remains were violated in 1630, possibly by thieves. These results are consistent with morphological investigations and confirm the importance of integrating molecular and morphological approaches in investigating historical remains.  相似文献   
132.
133.
134.
135.
136.
137.
We study the impact of tenure in office on economic performance. We evaluate the relationships between tenure in office and GDP growth, public capital growth, and public capital productivity using data for Spanish regions during the period 1980?C1998. We find that tenure decreases the impact of public capital growth on GDP growth. Our results suggest that tenure affects GDP growth negatively through a decrease in public capital productivity.  相似文献   
138.
Short tandem repeats (STR)s have been the eligible markers for forensic animal genetics, despite single‐nucleotide polymorphisms (SNP)s became acceptable. The technology, the type, and amount of markers could limit the investigation in degraded forensic samples. The performance of a 32‐SNP panel genotyped through OpenArraysTM (real‐time PCR based) was evaluated to resolve cattle‐specific forensic cases. DNA from different biological sources was used, including samples from an alleged instance of cattle rustling. SNPs and STRs performance and repeatability were compared. SNP call rate was variable among sample type (average = 80.18%), while forensic samples showed the lowest value (70.94%). The repeatability obtained (98.7%) supports the used technology. SNPs had better call rates than STRs in 12 of 20 casework samples, while forensic index values were similar for both panels. In conclusion, the 32‐SNPs used are as informative as the standard bovine STR battery and hence are suitable to resolve cattle rustling investigations.  相似文献   
139.
140.
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