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161.
目的:研究防风水提的最佳工艺条件。方法:以固形物量及其总多糖含量为考察指标,采用正交试验法,以提取时间(A)、加水量(B)、提取次数(C)为考察因素,每个因素设立3个水平进行试验。结果:各因素对防风水提液的固形物量均没有显著影响。因素C对总多糖的含量有显著影响,而因素A和B则无显著性差异。结论:最佳工艺为加水8倍量,提取3次,每次1 h。 相似文献
162.
Marta Concheiro Ana de Castro
scar Quintela Angelines Cruz Manuel Lpez-Rivadulla 《Forensic Science International Supplement Series》2007,170(2-3):156
The aim of this study was to assess the effectiveness of two current on-site oral fluid (OF) drug detection devices (OraLab and Dräger), as part of the Spanish participation in the Roadside Testing Assessment Project (ROSITA Project). The study was done in collaboration with the Spanish Traffic Police, in Galicia (NW Spain), during 2004 and 2005. A total of 468 drivers selected at the police controls agreed to participate through informed consent. In addition, saliva samples were collected and sent to the laboratory to confirm the on-site results. For this purpose, two different analytical liquid chromatography–mass spectrometry (LC–MS) methods were used to detect 11 drugs or metabolites in a 300 μL sample. Simultaneous analysis of morphine, 6-acetylmorphine, amphetamine, methamphetamine, MDA, MDMA, MDEA, MBDB, cocaine and benzoylecgonine was carried out using 100 μL of oral fluid, after an automated solid phase extraction. A different LC–MS method was performed to detect Δ9-THC in 200 μL of oral fluid using liquid–liquid extraction with hexane at pH 6. Both methods were fully validated, including linearity (1–250 ng/mL, 2–250 ng/mL) recovery (>50%), within-day and between-day precision (CV < 15%), accuracy (mean relative error < 15%), limit of detection (0.5 and 1 ng/mL), quantitation (1 and 2 ng/mL) and matrix effect. All of the positive cases and a random selection of 30% of the negatives were analyzed for confirmation analysis. Good results (sensitivity, specificity, accuracy, positive predictive value and negative predictive value > 90%) were obtained for cocaine and opiates by OraLab, and for cocaine by Dräger. However, the results for the other compounds could be improved for both detection devices. Differences in the ease of use and in the interpretation mode (visual or instrumental) were observed. 相似文献
163.
猪传染性胃肠炎病毒重组M蛋白免疫血清在病原检测中的应用 总被引:2,自引:0,他引:2
以纯化的猪传染性胃肠炎病毒(TGEV)重组M蛋白免疫新西兰兔,制备免疫血清,用间接ELISA测得免疫血清效价达1∶14 000。通过间接ELISA进行病原检测,表明制备的免疫血清与全病毒具有较好的特异性。用免疫血清进行病原间接免疫荧光检测,TGEV感染的细胞培养物中多数细胞在其胞浆和细胞膜上出现黄绿色闪亮荧光,且荧光强度强,而未接种病毒的细胞培养物未见有黄绿色闪亮荧光,表明用所制备的抗TGEV重组M蛋白的免疫血清进行病原间接免疫荧光检测具有较高的特异性,为TGEV准确快速诊断与鉴别奠定了基础。 相似文献
164.
刘颖 《陕西行政学院学报》2003,17(3)
心理测评手段由于它所具备的客观和标准等科学特征,已越来越被广泛用于人员招聘、人才选拔等重要管理领域。但我国心理测评尚处于起步阶段,仍存在许多问题。正视这些问题并加强应用领域的规范化管理,将对我国人力资源的市场化经营起到重要的促进作用. 相似文献
165.
兰良民 《陕西行政学院学报》2002,16(1)
词汇测试是语言测试的重要组成部分。要设计好英语词汇测试,应主要解决好两个问题,一是选择哪些词汇为代表;二是题目的设计形式。 相似文献
166.
孙若红 《辽宁公安司法管理干部学院学报》2003,(1):78-80
听力理解是语言多种能力的综合反映,任何一种能力的不足都会影响听力理解,阻碍听力水平的提高.本文通过分析IELTS听力测试内容的科学性和题型的多样性,论述了在课堂教学中采用真实听力材料和培养文化意识的必要性. 相似文献
167.
唾液中乙醇含量检测试剂条的研究 总被引:1,自引:0,他引:1
目的根据唾液和血液中乙醇含量相关性的实验结果,建立了一种简便快速、准确可靠的检测唾液中乙醇含量的方法。方法本方法利用酶学原理,将一定量乙醇氧化酶(ALO)和过氧化物酶以及底物四甲基联苯胺(TMB)固定于试剂条上,当样本中含有乙醇时,酶学反应使底物TMB显色,通过比对反应的不同颜色,对样本中乙醇质量浓度进行半定量。结果用本方法检测300个自愿者的唾液,和用GC/MS法对照检测志愿者唾液中的乙醇含量,定量结果基本一致。本产品检测过程仅需2min,其检测的阈值为0.1mg/mL,敏感度为96.5%,特异性为91%,准确性为94.7%。结论采用酶学方法制备的乙醇含量检测试剂条,通过显色反应对唾液中的乙醇含量进行半定量检测,其特点为快速简便、准确可靠,适合现场使用。 相似文献
168.
Charles P. Nemeth 《Forensic science international》1983,21(2):103-115
The polygraph is a machine which invades previously private regions in the human being. Its operation is often viewed simplistically and lacking in danger. Such naivete is the subject of this comment. The paper considers the mechanics of polygraph operation, and its theoretical basis; the legal admissibility of the polygraph in a variety of settings, and lastly the impact the polygraph has upon our private lives.Clearly, the polygraph intrudes on the private regions of each individual, and this frightening fact is cause enough to consider the human, social and constitutional implications of its use. The project considers the reliability factor of the polygraph and its questionable use in personnel and business settings; its use in disciplinary procedures and labor arbitration, as well as reviews its place in judicial process and criminal review.Most critically the paper attempts to arrive at a constitutional basis for restrictions on its use in the private sector. Ingenious arguments have been made by opponents of the polygraph, and this paper reviews the substance and content of these constitutional arguments. 相似文献
169.
170.
Screening Test for Shed Skin Cells by Measuring the Ratio of Human DNA to Staphylococcus epidermidis DNA 下载免费PDF全文
Hiroaki Nakanishi Ph.D. Takeshi Ohmori Ph.D. Masaaki Hara Ph.D. Shirushi Takahashi M.D. Ph.D. Akira Kurosu M.D. Ph.D. Aya Takada M.D. Ph.D. Kazuyuki Saito M.D. Ph.D. 《Journal of forensic sciences》2016,61(3):618-622
A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real‐time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples. 相似文献