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151.
Peter Zimmermann Kai Vollack Barbara Haak Michelle Bretthauer Andrea Jelinski Marga Kugler Jessica Loidl Werner Pflug 《Forensic Science International: Genetics Supplement Series》2009,2(1):62-63
Within the initial step of the forensic DNA analysis process, the DNA extraction efficiency and especially the removal of potential PCR inhibitors is crucial for subsequent steps, e.g. quantification by real-time PCR and amplification of short tandem repeats (STRs). The protocol of the PrepFiler™ Forensic DNA Extraction Kit was optimized for the application on a Tecan liquid handling workstation Freedom EVO® 150. This modified application of the PrepFiler™ technology was compared with respect to DNA yield, sensitivity and the ability to remove potential PCR inhibitors to an established routine method working on the same liquid handling workstation based on ChargeSwitch® Technology (CST) from Invitrogen. 相似文献
152.
死亡大鼠组织中总RNA提取的质量控制及方法评价 总被引:1,自引:0,他引:1
目的探讨不同商品化试剂盒在提取组织总RNA过程中的优劣与适用范围,为实验室的质量控制提供依据。方法采用以膜提取技术为基础(SV total RNA isolation system)和以异硫氰酸胍/苯酚法为原理(TRIzol总RNA提取试剂盒)的两种试剂盒对死亡大鼠心、肝、脾、肺、肾、脑组织进行总RNA的提取与评价鉴定,并使用琼脂糖变性凝胶电泳和2100芯片生物分析仪对提取的总RNA进行完整性鉴定和质量控制评价。结果两种商品化试剂盒提取的总RNA纯度与得率均可满足实验要求。各组织脏器中总RNA得率依次为脾脏>肝脏>肾脏>大脑>肺脏>心脏。结论与TRIzol总RNA提取试剂盒相比,SV Total RNA Isolation System提取时对操作人员熟练度要求较低,2100芯片生物分析仪有望替代凝胶电泳技术用于总RNA提取时的质量控制。 相似文献
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156.
计算机取证是打击计算机犯罪的有效手段,传统的计算机取证大多采用事后分析的静态取证技术,证据的采集不够及时、全面,经恢复的数据可能是已经被篡改,因而法律效力低。可以运用一种将计算机取证技术与入侵检测技术结合的入侵动态取证系统,动态收集识别入侵证据,及时分析、提取证据至证据库中保存。此系统采用认证、加密、隔离等安全手段,确保了证据在传送、保存过程中的真实性、准确性及不可篡改性,使其成为有效的法庭证据,实现了计算机取证的及时性、智能性。 相似文献
157.
Benjamin Neimark 《The Journal of peasant studies》2013,40(2):423-445
The following article contrasts contemporary rosy periwinkle (Catharanthus roseus) extraction in southern Madagascar with original bioprospecting research conducted 50 years ago. My study shows how plant extraction firms have shifted their approaches by creating new labor forms, which devolve risk and increase exploitation in attempts to capture the valuable biogenetic material needed for drug discovery. The periwinkle symbolizes a complex picture of many dynamic barriers to capitalist penetration at work, including the natural, social and political. Over time, these barriers change and act in conjunction to provide a complex commodity chain expressing many exploitative labor relations of green capitalism. 相似文献
158.
To validate information on cannabis use, we investigated human hair and pubic hair for cannabinoids (THC and THC-COOH) by gas chromatography/mass spectrometry. Samples (100 mg approximately) were decontaminated with methylene chloride, then pulverized and dissolved in 1 ml 1 N NaOH for 10 min at 95 °C in the presence of 200 ng of deuterated standards. After cooling, samples were extracted by n-hexane/ethyl acetate after acidification with acetic acid. After derivatization of the dry extract by PFPA/PFP-OH, the drugs were separated on a 30-m capillary column and detected using selected-ion monitoring (m/z 377 and 459 for THC and THC-COOH, respectively). Forty-three hair samples were obtained from fatal heroin overdose cases. Among them, 35% tested positive for cannabinoids. Hair concentrations ranged from 0.26 to 2.17 ng/mg (mean, 0.74 ng/mg) and 0.07 to 0.33 ng/mg (mean, 0.16 ng/mg) of THC and THC-COOH, respectively. As is generally the case for other drugs detected in hair, metabolite concentration was always lower when compared to the parent drug concentration. In pubic hair, THC concentrations ranged from 0.34 to 3.91 ng/mg (mean, 1.35 ng/mg) and THC-COOH concentrations from 0.07 to 0.83 ng/mg (mean, 0.28 ng/mg). In most cases, the highest cannabinoid concentration was found in pubic hair, suggesting that this sample may be the more suitable for cannabis testing. 相似文献
159.
Testing human hair for drugs of abuse is a relatively new technique which requires control before being fully accepted in Justice applications. A consensus procedure was recently proposed to the four French Laboratories performing hair analysis for opiates and cocaine. Results of two independent controls have shown that the laboratories have performed very well quantitatively, using the recommended method. In order to compare these results with those obtained by other procedures, one sample was sent to 15 laboratories concerned with the analysis of human hair for drugs of abuse in Germany, Italy, Spain, and United States. Results from this study have indicated that the French recommended method is in accordance with the general procedures. 相似文献
160.
快速溶剂萃取技术是近几年出现的一种新的适用于复杂检材前处理的、高效、快速、简便、理想的萃取方法。快速溶剂萃取法的原理、特点、仪器装置与操作步骤、影响因素在刑事技术领域的应用。 相似文献