全文获取类型
收费全文 | 1271篇 |
免费 | 59篇 |
专业分类
各国政治 | 48篇 |
工人农民 | 90篇 |
世界政治 | 164篇 |
外交国际关系 | 55篇 |
法律 | 682篇 |
中国共产党 | 2篇 |
中国政治 | 18篇 |
政治理论 | 227篇 |
综合类 | 44篇 |
出版年
2023年 | 13篇 |
2022年 | 11篇 |
2021年 | 13篇 |
2020年 | 39篇 |
2019年 | 37篇 |
2018年 | 50篇 |
2017年 | 51篇 |
2016年 | 46篇 |
2015年 | 43篇 |
2014年 | 46篇 |
2013年 | 147篇 |
2012年 | 65篇 |
2011年 | 49篇 |
2010年 | 49篇 |
2009年 | 42篇 |
2008年 | 69篇 |
2007年 | 61篇 |
2006年 | 51篇 |
2005年 | 70篇 |
2004年 | 49篇 |
2003年 | 44篇 |
2002年 | 39篇 |
2001年 | 34篇 |
2000年 | 28篇 |
1999年 | 12篇 |
1998年 | 21篇 |
1997年 | 5篇 |
1996年 | 10篇 |
1995年 | 13篇 |
1994年 | 6篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 10篇 |
1989年 | 8篇 |
1988年 | 11篇 |
1987年 | 3篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 8篇 |
1981年 | 4篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 4篇 |
1972年 | 2篇 |
1967年 | 3篇 |
1963年 | 1篇 |
排序方式: 共有1330条查询结果,搜索用时 0 毫秒
971.
Betel quid (BQ) chewing, a common tradition in tropical areas, often poses a problem during collection and DNA analysis of buccal samples from many indigenous communities for population genetic studies and in forensic analysis of chewed BQ residues. This study evaluated the use of FTA card, a chemically treated filter paper, in collecting buccal samples from long-term BQ users and subsequent PCR-based analysis using nine STR markers. A low overall success rate of amplification was observed in the samples extracted using a standard organic extraction procedure (7%) as compared with those prepared using the FTA card (89%). The presence of inhibitors in liquid DNA samples was verified when control DNA failed to amplify in the presence of an equal volume of liquid BQ samples. The use of the FTA card is more practical during field sampling than handling tubes containing buccal swabs. 相似文献
972.
Bieschke ET Wallace MM De Forest PR Shaler RC Prinz M 《Journal of forensic sciences》2003,48(1):80-82
The FES short tandem repeat (STR) locus contains seven to 14 repeats of the tetranucleotide sequence ATTT. A novel 10 base pair dimorphism in the 5' flanking region of the FES locus was characterized in four broad populations: African-American, Hispanic, Caucasian, and Asian. The absence of the 10 base pair sequence, or (-) allele, was closely linked to FES STR alleles with 10 or fewer repeats. The presence of the 10 base pair sequence, or (+) allele, was closely linked to FES STR alleles with 12 or more repeats. The (-) and (+) alleles occurred equally often in FES STR allele 11. The nucleotide sequence (5'-GGCTGTTTTG-3') of the (+) allele, located 179 base pairs upstream of the FES STR, was determined to be consistent within and among the four populations. Statistical and sequence analysis confirmed the linkage between the two polymorphic sites. The results indicate that the exclusion rate of the FES locus is increased, above that for the STR alone, when both polymorphic characteristics are considered. 相似文献
973.
Coopman VA Cordonnier JA De Letter EA Piette MH 《Forensic science international》2003,134(2-3):115-119
This article describes the toxicological findings in a fatality due to an accidental inhalation of trichloroethylene which took place during wall coating of a poorly ventilated well using trichloroethylene. The man was wearing protective clothing and a mouthmask with adsorbent. He was found dead on the floor of the well 5h after descending. Trichloroethylene was added to the mortar to enhance drying. Identification and quantitation of trichloroethylene in the postmortem samples (blood, lung, liver, kidney, stomach content and bile) and identification of its metabolite trichloroacetic acid in urine was performed using static headspace gas chromatography with mass spectrometric detector. The compounds were separated on a CP-SIL 5CB Low Bleed/MS column using n-butanol as internal standard. The method was linear over the specific range investigated, and showed an accuracy of 104% and an intra-day precision of 11%. Trichloroethylene concentrations of 84mg/l in subclavian blood, 40mg/l in femoral blood, 72mg/kg in liver, 12mg/kg in kidney, 78mg/kg in stomach content, 104mg/l in bile and 21mg/kg in lung were found. Trichloroacetic acid was identified in the urine. 相似文献
974.
975.
976.
977.
978.
赵一德 《浙江青年专修学院学报》2005,(1):1-6
进入新世纪新阶段,国际形势画龙点睛在发生深刻变化.我国正处于改革发展的关键时期,共青团工作面临首难得的机遇和严峻的挑战. 相似文献
979.
980.