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   1229篇
  免费   62篇
外交国际关系   42篇
法律   1208篇
中国政治   8篇
政治理论   2篇
综合类   31篇
  2024年   4篇
  2023年   25篇
  2022年   60篇
  2021年   23篇
  2020年   38篇
  2019年   59篇
  2018年   32篇
  2017年   17篇
  2016年   37篇
  2015年   24篇
  2014年   31篇
  2013年   91篇
  2012年   61篇
  2011年   77篇
  2010年   53篇
  2009年   120篇
  2008年   103篇
  2007年   110篇
  2006年   116篇
  2005年   33篇
  2004年   24篇
  2003年   25篇
  2002年   31篇
  2001年   25篇
  2000年   21篇
  1999年   5篇
  1998年   8篇
  1997年   3篇
  1996年   7篇
  1995年   2篇
  1994年   7篇
  1993年   3篇
  1992年   1篇
  1991年   4篇
  1990年   5篇
  1989年   4篇
  1988年   2篇
排序方式: 共有1291条查询结果,搜索用时 15 毫秒
71.
DNA mixture interpretation is undertaken either by calculating a LR or an exclusion probability (RMNE or its complement CPI). Debate exists as to which has the greater claim. The merits and drawbacks of the two approaches are discussed. We conclude that the two matters that appear to have real force are: (1) LRs are more difficult to present in court and (2) the RMNE statistic wastes information that should be utilised.  相似文献   
72.
以旋毛虫(Trichinelaspiralis)国际标准虫种作对照,利用随意扩增的DNA多态性技术对国内的部分旋毛虫分离株进行了鉴定与分析。经5条引物的单扩增及复合扩增结果显示,中国的旋毛虫猪株为T.spiralis,犬株为T.na-tiva,猫株为T.nelsoni。  相似文献   
73.
建立的天津市法医DNA数据库系统 ,将DNA分析技术的高效性与计算机系统的储存、高效检索的功能有机结合 ,实现了从受案到结案及建库的全程标准化、规范化、网络化管理。该系统启用一年多以来 ,为本地区侦查机关提供了百余起案件的破案线索 ,在多起重特大刑事案件的串并侦破中发挥了关键作用 ,技术破案率明显提高  相似文献   
74.
张明  严华 《刑事技术》2003,(Z1):20-21
本文选择Promega公司的3个复合扩增系统对荆州地区汉族人群进行了基因频率调查,获得了9个STR基因座的群体遗传学参数,报告如下。1材料与方法1.1实验材料1.1.1样本146例汉族无关个体血样来自荆州市各县市区,系本实验室日常检案积累。1.1.2主要仪器设备eppendorf-5331型扩增仪(eppendorf公司);model-4001型电泳仪及SA-32型电泳槽(GIBCO公司)。1.1.3主要试剂Chelex-100(Bio-Rad公司);Taq酶(Promega公司);3个复合扩增试剂盒(Promega公司)。1.2实验方法1.2.1模板DNA的制备所有血样均用5%chelex-100快速提取DNA。1.2.2复合扩增扩增总体…  相似文献   
75.
毒鼠强诱导细胞DNA损伤的彗星电泳检测   总被引:1,自引:0,他引:1  
目的 研究毒鼠强对小鼠淋巴细胞和脑细胞DNA的损伤作用。方法 分离健康小鼠的淋巴细胞和脑细胞 ,以彗星电泳的方法测定不同浓度毒鼠强处理后的细胞DNA损伤。结果  1/2 0~ 1/2LD50 剂量组的毒鼠强均可引起淋巴细胞和脑细胞不同程度的DNA损伤 ,与对照组呈极显著性差异 (P <0 0 0 1)。结论 毒鼠强引起细胞DNA断裂损伤 ,并呈现明显的剂量 -效应关系。  相似文献   
76.
Competitive PCR assays were established for the mitochondrial DNA hypervariable region I and the human amelogenin locus. Using these assays, the copy numbers of DNA participating in PCR (amplifiable DNA) were quantified in tissues exposed to different environments. Human ribs, skin and nails were left in three exposure conditions (in the open air, in soil and in water). The amounts of amplifiable DNA in these tissues were quantified during a time period of up to two months. The amount of amplifiable DNA was well preserved in hard tissues (ribs and nails) regardless of the exposure conditions, whereas the soft tissues immersed in water showed a rapid decrease in amplifiable DNA. Strong PCR inhibition was observed in the DNA extracts obtained from buried bones. This phenomenon was clearly identified from an amplification failure of the internal standards in the competitive PCR. A preliminary examination to identify the PCR inhibitor suggested that the soil itself contributed to the inhibition. In addition, the amounts of amplifiable DNA in case samples were also investigated.  相似文献   
77.
综述了血指印和汗潜指印生物遗传标记的研究历史和现状,指印DNA检验面临的问题,包括现场污染,显现剂的影响,载体的影响等,并对指印DNA在法医学中的应用前景进行了展望。  相似文献   
78.
在实际检案中,经常遇到案发现场可获取的生物检材量微,在进行必要的种属检验、精斑确证实验、ABO血型检验等常规物证初检后,便无多余的生物检材移送DNA实验室进一步做法医DNA检验。因此,笔者通过对检案中遇到的上述微量物证检材的再行处理利用,在本实验室条件下,对其进行了TH01、HUMACTBP2、AluVpA、DIS80等位点的DNA-PCR分析,获得了良好的效果。使其在实际办案中更充分地发挥了证据作用,报告如下。1材料与方法检案中已经种属或ABO血型检验后的血痕、唾液斑(如烟蒂外层纸)浸泡凹板,加入300μl去离子水,…  相似文献   
79.
《Science & justice》2021,61(5):542-554
This study investigates the effectiveness of forensic evidence in UK volume crime investigations. The main aim was to identify characteristics of forensic evidence that influence its effectiveness in converting detections into criminal charges, as well as to critically consider the effectiveness of a recent service level agreement (SLA) implemented by Wiltshire Police, which aimed at reducing CSI attendance. The sample consisted of 445 police recorded cases received from Wiltshire Police. Presence or absence and location-related characteristics of fingerprint, DNA, and footwear evidence were evaluated on the effectiveness of forensic evidence and examined within the contexts of different volume crimes. Results showed a high level of correlation in converting detections into criminal charges where the presence of DNA, footwear, and multiple evidence types was recorded; and a positive correlation between forensic evidence ineffectiveness and presence of fingerprints, particularly in residential burglaries. Differences between individual offence types were expressed. The most prominent feature influencing the effectiveness of forensic evidence was found to be related to the movability of the exhibit associated with the recovered evidence, with DNA recovered from non-movable items presenting the strongest effectiveness. Cases processed after the implementation of the SLA did not show significant differences in forensic evidence effectiveness as compared to cases processed prior to the SLA, however, they demonstrated a lack in effectiveness of DNA evidence. The findings of the current research provide a better understanding of the contextual influences on the potential of forensic evidence and can support improvement of crime scene screening and CSI resource deployment.  相似文献   
80.
Studying dipterans at the scene of a death can provide essential information for interpreting the evidence and help to reconstruct the events happened to a corpse in the past. Molecular tools have been employed for identification at specific levels in the cases of cryptic species or poorly conserved specimens. Identification of specimens is essential in forensic entomology since each species has a specific growth rate, which determines the calculation of the minimum post mortem interval (minPMI). In addition, phylogeographic reconstruction within a species can help to differentiate the haplotypes from a geographic area, thereby helping to clarify the possible relocation of a corpse. The morphological identification of Sarcophagidae species is often difficult, especially for the females. This is an important Diptera family since some of its species are among the first to reach a corpse, especially in warm areas. In this study, we compared the sarcophagids found in human corpses in forensic cases in Alicante (southeast of Spain) with specimens collected from baited traps in the same area and surrounding provinces. In total, 189 specimens were collected, comprising 72 from forensic cases and 117 from baited traps. Molecular identification was conducted by sequencing the cox1 mitochondrial gene and analyzing the sequences using ABGD, GMYC, and BIN species delimitation methods. The median joining algorithm in the PopART program was used to construct phylogeographic networks. Eight species in the family Sarcophagidae were identified. The most widely collected species were Sarcophaga argyrostoma and Sarcophaga tibialis. The haplotype networks obtained for these species did not indicate a clear geographic distribution of haplotypes. The S. argyrostoma samples from Alcoy were clearly isolated. The results demonstrated that this method is useful for identifying Sarcophagidae samples in forensic investigations and it can be employed for minPMI estimation.  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