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   1929篇
  免费   132篇
各国政治   183篇
工人农民   126篇
世界政治   223篇
外交国际关系   103篇
法律   1075篇
中国政治   4篇
政治理论   344篇
综合类   3篇
  2023年   29篇
  2022年   17篇
  2021年   43篇
  2020年   63篇
  2019年   73篇
  2018年   111篇
  2017年   153篇
  2016年   120篇
  2015年   84篇
  2014年   101篇
  2013年   279篇
  2012年   92篇
  2011年   72篇
  2010年   40篇
  2009年   39篇
  2008年   66篇
  2007年   68篇
  2006年   63篇
  2005年   62篇
  2004年   65篇
  2003年   68篇
  2002年   58篇
  2001年   55篇
  2000年   32篇
  1999年   25篇
  1998年   13篇
  1997年   20篇
  1996年   9篇
  1995年   8篇
  1994年   4篇
  1993年   6篇
  1992年   9篇
  1991年   9篇
  1990年   8篇
  1989年   9篇
  1988年   8篇
  1987年   7篇
  1985年   4篇
  1984年   4篇
  1983年   4篇
  1982年   5篇
  1979年   4篇
  1978年   4篇
  1974年   3篇
  1973年   7篇
  1972年   7篇
  1971年   11篇
  1968年   4篇
  1966年   3篇
  1965年   2篇
排序方式: 共有2061条查询结果,搜索用时 281 毫秒
81.
Allele and genotype frequencies for three recently described short tandem repeat loci D1S1656, D12S391, and D18S535 were determined in a population sample from Asturias (North Spain). The loci were amplified using a fluorescence based PCR method and were typed automatically. No deviation from Hardy-Weinberg expectations were observed. The three loci proved to be highly discriminating and the allele frequencies observed are similar to those of the other European populations that have been typed for these loci to date.  相似文献   
82.
83.
ABSTRACT

This paper analyzes simultaneous strikes during the first half of the 20th century in North America. The transformation of production in copper, lead, zinc, and silver mining districts determined the formation of a working class that operated between Mexico and the United States. Therefore, the labor conflicts combined market circumstances and management-imposed homologation of work structures across firm divisions with the international coordination of miners. The paper describes the emergence, growth, and demise of a regional industrial system.  相似文献   
84.
“Albeit democratic, their coat of arms has pride of place”. Thus Romualdo Nogués defined, in 1890, Spanish collectors of bourgeois origin who had joined the ranks of the aristocracy. A few years later, in 1924, the Duke of Alba’s maiden speech at the Academia de Bellas Artes de San Fernando justified his personal artistic worthiness on the basis of his ancestors’ collecting activities and the artworks they had amassed.

These two examples set the scene for the research questions studied in this monographic issue. The present introduction offers a bird’s eye view of the phenomenon and continues with a few remarks about the House of Osuna which, as is well known, occupied a pivotal position in Spanish nobility during the whole of the second half of the nineteenth century.  相似文献   

85.
86.
This ecological study examined the association between seven socioeconomic indicators (GDP, unemployment rate, female labor force participation rate, alcohol expenditure, marriage rate, percentage of births outside of marriage, and indictable crime rate) and total, male, and female rates of suicide and suicide plus undetermined death in Ireland during the period 1968-2000. Analysis of the data expressed as absolute values showed highly significant associations between the socioeconomic indicators and the total, male, and female suicide rates. However, these associations were explained by the strongly trended data. The trended nature of the data was removed by using year-to-year differences. Analysis of the first-differenced data showed that none of the socioeconomic indicators was associated with the total, male, or female suicide rates with the exception of indictable crime, which had a significant independent effect on the female suicide rate (coefficient = 2.0, p < .01) but not on suicide plus undetermined death. This study highlights the need to use econometric methods in time-trend analyses, the lack of age-sex specific exposure data in this area, and the challenge of understanding trends in suicide in their socioeconomic context.  相似文献   
87.
88.
A clear positive case for anabolic steroids doping was confounded by alleged urine tampering during doping control procedures. Review of the chain of custody showed no flaws, but nevertheless the athlete was adamant that the urine sample should be analyzed for DNA in order to support her contention that she was not the donor of the sample. The results obtained showed that the urine sample that scored positive for steroids contained nuclear DNA that could not be matched to the DNA obtained from the athlete's blood. On the other hand, the same urine sample contained mitochondrial DNA whose nucleotide sequences spanning the hyper variable regions HV1 and HV2 proved to be identical to those determined in mitochondrial DNA amplified from the athlete's blood. The occurrence of an extraneous genotype is compatible with exogenous nuclear DNA admixture to the athlete's urine. Alternatively, taking in consideration the mitochondrial DNA, we could not exclude that a sibling or a maternal relative of the athlete could have acted as a donor of the urine utilized for doping control and DNA analysis. Both situations point to possible tampering of the urine by the athlete. Adjudication at CAS maintained previous national and international federation decision that there was no proof of a chain of custody flaw to justify the athlete's allegation of urine substitution after collection.  相似文献   
89.
90.
Nine Y-STR loci from the "minimal haplotype" included in Y-STR Haplotype Reference Databases (YHRD) together with eight additional Y-STRs (DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10) were analyzed in a sample of 101 males from Equatorial Guinea living in Madrid. Haplotype and allelic frequencies were calculated and genetic diversities were estimated for each genetic system as well as for the whole haplotype. An unexpected high frequency (6%) of intermediate alleles (13.2 and 14.2) was found in DYS385. For DYS19, two alleles were found in one sample. Another sample failed to amplify with DYS393 primers using either PowerPlex Y System (Promega Corporation) or the Y-PLEXtrade mark 12 (Reliagene, New Orleans, LA) commercial kits. Comparison between Equatorial Guinea and another African population (Mozambique; South East Coast) revealed a significant pairwise Phi(st) value between them (Phi(st)=0.03309; P=0.00000).  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