全文获取类型
收费全文 | 1230篇 |
免费 | 65篇 |
专业分类
外交国际关系 | 42篇 |
法律 | 1206篇 |
中国政治 | 11篇 |
政治理论 | 3篇 |
综合类 | 33篇 |
出版年
2024年 | 4篇 |
2023年 | 25篇 |
2022年 | 57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 | 33篇 |
2013年 | 92篇 |
2012年 | 61篇 |
2011年 | 78篇 |
2010年 | 54篇 |
2009年 | 120篇 |
2008年 | 103篇 |
2007年 | 110篇 |
2006年 | 116篇 |
2005年 | 33篇 |
2004年 | 25篇 |
2003年 | 26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1295条查询结果,搜索用时 15 毫秒
61.
Sodium hypochlorite is an efficient reagent for removal of unwanted DNA from laboratory surfaces. Here, we tested two different chlorine wipes and compared their performance to a 0.9–1.8% hypochlorite solution. WipeClean Chlorine Disinfection wipes contain > 0.1 g sodium hypochlorite/kg, whereas WetWipe Chlorine Desinfection wipes contain > 1000 ppm active chlorine. Clean surfaces were contaminated with 10 µL 0.5 ng/µL of massively parallel sequencing libraries. The DNA was dried and left for 45 min before any treatment. The surfaces were cleaned using either 1) a 0.9–1.8% hypochlorite solution and clean wipes, 2) a WipeClean wipe, 3) a WetWipe, or 4) the surface was not cleaned. All experiments were repeated three times. Subsequently, the surfaces were swabbed using cotton swabs. DNA was extracted from the swabs and the DNA concentrations were determined in quadruplicates by real-time PCR. This protocol was repeated after the soft plastic wrapping around the wipes were left open or closed for several weeks. The results showed that the WipeClean wipes efficiently removed DNA for up to four weeks after the box with the wipes were opened, whereas the WetWipe wipes dried faster and gradually lost their cleaning effect. 相似文献
62.
目的探讨鞋内底不同部位接触DNA提取检出率。方法取100名20-30岁的志愿者,将其穿用过的运动鞋和皮鞋鞋垫设置成不同穿用时间组、不同材料鞋垫组、穿用后不同放置时间组,根据脚的形态学及运动力学特点,将鞋垫分成8个区域进行脱落细胞提取,并进行DNA进行检验。结果鞋垫上8个不同区域提取到的脱落细胞DNA分型检验效果不同。足弓外侧区(足引折弓除外)的接触DNA检出率最高;足弓内侧、第1趾骨区、第1跖骨区及足跟区次之;第2~5趾骨区、第2~3跖骨区、第4~5跖骨区不容易成功提取到接触DNA。结论鞋内底接触DNA检出率与接触时间、放置时间、鞋垫材质均相关,分区提取检验DNA更有针对性。 相似文献
63.
John Buckleton James Curran 《Forensic Science International: Genetics Supplement Series》2008,2(4):343-348
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
64.
65.
黄建平 《吉林公安高等专科学校学报》2008,23(6):60-64
DNA证据在刑事司法程序中有着独特的自身价值,但这并不意味着DNA证据就是完美无缺的“证据之王”。在当前我国的刑事司法领域中,关于DNA的鉴定和证据适用等方面还存在着诸多的问题。因此,我国应在DNA证据采信等环节上建立和完善相应规则,克服对DNA证据的盲目轻信。 相似文献
66.
67.
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
68.
69.
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
70.