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   201篇
  免费   20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 93 毫秒
141.
142.
143.
144.
145.
146.
A rapid and highly species-specific real-time polymerase chain reaction (PCR) assay has been developed for the detection of capercaillie DNA (Tetrao urogallus) in meat and meat mixtures. The method combines the use of capercaillie-specific primers, that amplify a 142bp fragment of the mitochondrial 12S rRNA gene, and a positive control primer pair that amplifies a 141bp fragment of the nuclear 18S rRNA gene from eukaryotic DNA. SYBR(?) Green dye or TaqMan(?) fluorogenic probes were used to monitor the amplification of the target genes. Results obtained with the use of TaqMan(?) probes as detection platform increased the specificity of the real-time PCR assay in comparison with the results obtained using SYBR(?) Green. The proposed real-time PCR assay represents a rapid and straightforward method for the accurate identification of capercaillie that could be used by law enforcement agencies as a tool for the control of poaching and illegal trade of meat from this protected species.  相似文献   
147.
This paper describes a sensitive UPLC-MS/MS method for quantification of methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in single empty puparial case of Lucilia sericata. Larvae were reared on substrates spiked with different concentrations of methadone (0-4 μg/g). Methadone was quantified in puparia reared on high concentrated substrates (0.8-4 μg/g). The major metabolite of methadone (EDDP) was not detected, confirming rapid elimination of metabolites by the larvae before pupation. The effects of methadone on the development of L. sericata were also investigated. No effect on sex ratio was detected. A significant difference was calculated for emerged adults but no trends could be observed. Concerning the developmental curve, a significant difference was observed between control and high methadone concentrations using the Kolmogorov-Smirnov test.  相似文献   
148.
Population frequencies for the eight Y-STR loci included in the "minimal haplotype" from Y-STR Haplotype Reference Database (YHRD) plus other eight Y-STRs (DYS434, DYS435, DYS436, DYS437, DYS438, DYS439, GATA H4 and GATA A10) were obtained for a sample of 133 males from four main geographical areas in the Pyrenees (Spain): Vall D'Aran (Lérida), Cerdanya (Gerona), Alt Urgell (Lérida) and Jacetania (Huesca). Haplotype diversities were estimated in the four populations.  相似文献   
149.
As a grave is an anomalous environment and differs from its surroundings, criminal investigators employ different techniques for locating, recovering, and analyzing clandestine graves. In this study were identified the fungi found in the soil under corpses in decomposition with an aim at relating the copresence of human remains and different fungal species. Were isolated the fungi in three ways: soil washing, serial dilutions, and moist chamber growth. Dichotomomyces cejpii, Talaromyces trachyspermus, Talaromyces flavus, and Talaromyces sp. were the representative species found—with those belonging to the ammonia group, whose fungi are the first in the succession of cadaver decomposition directly in the ground. The mycobiota found at the present study area clearly differs to mycobiota identified in control sample and from previously described species for other areas of Buenos Aires Province, Argentina. Further forensic examples of this type are needed to develop fully the detailed use of mycology as a forensic tool.  相似文献   
150.
We herein report the case of a 36‐year‐old man who died suddenly after a fight with another man. Forensic investigations included unenhanced computed tomography, postmortem angiography, autopsy, histology, neuropathology, toxicology, and biochemistry and allowed a traumatic cause of death to be excluded. An electrocardiogram recorded some years prior to death revealed the presence of an early repolarization pattern. Based on the results of all investigations, the cause of death was determined to be cardiac arrhythmia and cardiac arrest during an emotionally stressful event associated with physical assault. Direct third party involvement, however, was excluded, and the manner of death was listed as natural. The case was not pursued any further by the public prosecutor.  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