全文获取类型
收费全文 | 3273篇 |
免费 | 206篇 |
专业分类
各国政治 | 329篇 |
工人农民 | 198篇 |
世界政治 | 389篇 |
外交国际关系 | 220篇 |
法律 | 1691篇 |
中国共产党 | 1篇 |
中国政治 | 18篇 |
政治理论 | 606篇 |
综合类 | 27篇 |
出版年
2023年 | 44篇 |
2022年 | 30篇 |
2021年 | 65篇 |
2020年 | 108篇 |
2019年 | 150篇 |
2018年 | 183篇 |
2017年 | 243篇 |
2016年 | 200篇 |
2015年 | 141篇 |
2014年 | 182篇 |
2013年 | 546篇 |
2012年 | 158篇 |
2011年 | 132篇 |
2010年 | 85篇 |
2009年 | 75篇 |
2008年 | 119篇 |
2007年 | 131篇 |
2006年 | 113篇 |
2005年 | 93篇 |
2004年 | 110篇 |
2003年 | 98篇 |
2002年 | 73篇 |
2001年 | 59篇 |
2000年 | 54篇 |
1999年 | 32篇 |
1998年 | 28篇 |
1997年 | 30篇 |
1996年 | 11篇 |
1995年 | 18篇 |
1994年 | 10篇 |
1993年 | 14篇 |
1992年 | 15篇 |
1991年 | 14篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1978年 | 4篇 |
1974年 | 7篇 |
1972年 | 6篇 |
1971年 | 4篇 |
1968年 | 4篇 |
1967年 | 5篇 |
1966年 | 6篇 |
1965年 | 4篇 |
排序方式: 共有3479条查询结果,搜索用时 31 毫秒
171.
172.
173.
174.
175.
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
176.
177.
Sípoli Marques MA Pinto Damasceno LM Gualberto Pereira HM Caldeira CM Pereira Dias BF de Giacomo Vargens D Amoedo ND Volkweis RO Volkweis Viana RO Rumjanek FD Aquino Neto FR 《Journal of forensic sciences》2005,50(3):587-592
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
178.
Alunni-Perret V Muller-Bolla M Laugier JP Lupi-Pégurier L Bertrand MF Staccini P Bolla M Quatrehomme G 《Journal of forensic sciences》2005,50(4):796-801
The authors report on their macro- and microscopy study of bone lesions made by a sharp force instrument (a single blade knife), and a sharp-blunt instrument classified as a chopping weapon (a hatchet). The aim of this work was to attempt to identify the instrument by analyzing the general class characteristics of the cuts. Each weapon was used on human bones. The results indicate that macroscopic analysis is more problematic. The microscopic analysis assessed that characteristics examined were effective in distinguishing sharp from sharp-blunt injury to the bone. The microscope facilitates analysis unachievable with macroscopic methods, some three-dimensional characteristics not visible to the naked eye being clearly defined with its use. Emphasis has been placed on the value of SEM as an anthropologist's tool in bone lesion injuries. 相似文献
179.
180.
Genetic variability of 16 Y-chromosome STRs in a sample from Equatorial Guinea (Central Africa) 总被引:3,自引:0,他引:3
Arroyo-Pardo E Gusmão L López-Parra AM Baeza C Mesa MS Amorim A 《Forensic science international》2005,149(1):109-113
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