气相色谱-串联质谱法分析尿和血中除草剂百草枯

目的建立尿和血中百草枯的离子交换固相萃取-气相色谱-串联质谱分析方法。方法尿样加内标乙基百草枯,用732阳离子交换树脂提取;血样加内标乙基百草枯,用三氯乙酸凝聚蛋白质后取上清液用732阳离子交换树脂提取。提取物用硼氢化钠在水溶液中碱性条件下还原,还原物用有机溶剂提取进行气相色谱-串联质谱法分析。结果尿和血中百草枯的提取率分别为76％和74％,检测限分别为2ng／mL和10ng／mL,尿添加百草枯100ng／mL和血添加百草枯500ng／mL水平的回收率分别为99．6±5．6％和99．3±7．6％（Mean±CV）。结论本文建立的分析方法灵敏度高,能够满足中毒致死案件检验及临床毒物检验的需要。     

氯硝安定在生物体内的代谢

目的推测氯硝安定在生物体内的主要代谢方式,检测其代谢产物。方法取5只Wistar大鼠,连续3d给每只大鼠灌胃氯硝安定（剂量分别为1、2、2mg）,收集灌胃后24h内尿液;给3只大鼠各灌胃2mg氯硝安定,2h后处死,取血液和肝组织等检材;收集3名口服5mg氯硝安定的志愿者24h内尿液。分别对不同检材进行处理后,气相色谱/质谱联用（GC/MS）检测。结果在大鼠阳性尿液和志愿者阳性尿液中,均检出7-乙酰氨基氯硝安定和7-氨基氯硝基安定;在大鼠血液中,主要检出氯硝安定和7-氨基氯硝基安定;在大鼠肝组织中,主要检出7-乙酰氨基氯硝安定,还有少量7-氨基氯硝安定和氯硝安定。结论氯硝安定进入生物体后,其7位硝基被还原为氨基,氨基接着被乙酰化,形成7-氨基氯硝基安定和7-乙酰氨基氯硝安定代谢物,其中7-乙酰氨基氯硝安定为主要代谢物。     

FUT2/01基因座在中国北方汉族人群中的多态性

目的调查STR基因座FUT2/01在中国人群中的基因结构特征及其在中国人群中的多态性分布特点,并对其法医学应用前景进行探讨。方法应用PCR方法扩增FUT2/01基因,DNA测序确定所有等位基因的序列;常规聚丙烯酰胺凝胶电泳调查中国人群中FUT2/01基因座的多态性分布,同时应用荧光标记引物进行自动化检测分析和基因型鉴定。结果DNA测序结果仅显示核心序列的重复数目变化所导致的长度差异;在所调查的中国汉族人群162例个体中共发现9种等位基因和28种基因型,系统的个体识别率为0.9639,父权排除率为0.6266。此外,荧光标记引物经自动化检测可对该基因座进行良好的分型。结论FUT2/01基因座在中国汉族人群中表现出高度的杂合性和个体特异性,在法医学鉴定中具有较高的应用价值。     

分散固相萃取法测定人体血液中曲马多含量

目的建立一种测定人体血液中曲马多含量的规范化方法。方法采取分散固相萃取,以乙腈为提取剂,用无水硫酸镁为脱水剂,应用PSA（乙二胺N丙基硅烷）和C18进行净化,在柱温：90℃保持1min,以20℃／min升至280℃,保持7min条件下进行分析。结果曲马多的浓度在2-10ug／ml范围内,质量浓度和峰面积呈线性关系,线性方程为y=1232975．3x773017．8,相关系数为0．9982,回收率在83．729／6～91．58％之间,相对偏差为3．05％。结论此方法准确、灵敏,稳定性好,且提取过程中不易出现乳化。     

有机炸药的气相色谱-串联质谱分析

应用气相色谱-串联质谱（GC／MS-MS）分别采用EI／MS、PCI／MS、NCI／MS以及EI／MS-MS、NCI／MS-MS的方法分析六种有机炸药,通过不同检测方法的检测限比较,建立了适用于法庭科学的有机炸药检测方法。     

The modern trends in alcohol, drugs and driving research

Research on alcohol, drugs and driving can be broadly separated into experimental and epidemiological studies. Every approach has its inherent advantages and disadvantages. Experimental studies can result in an interpretation by single cause, but can only identify potential risks, and the results can sometimes be of limited value because of the use of non-realistic doses or because of the drug use history or inter-individual differences of the volunteers. Recent studies have used higher, more realistic doses and paid more attention to the combination of alcohol and drugs and have shown that the chronic use of illicit drugs can be associated with some cognitive and/or psychomotor impairment, and can lead to a decrease in driving performance even when the subject is no longer intoxicated.Epidemiological studies include roadside surveys, studies in a subset of drivers, accident risk studies, responsibility analyses, surveys and pharmaco-epidemiological studies. Between studies, results may be incomparable due to testing different populations, different kinds of samples, etc. More large-scale roadside studies are conducted now.Advances in analytical toxicology have also contributed to a better understanding of the risks associated with driving under the influence. While older studies measured the inactive metabolite THC-COOH and did not show an increased risk in cannabis-positive drivers, more recent studies measured the active THC in blood and did show a concentration dependent increase in crash risk. The use of LC–MS/MS has allowed more broad-range screening as this technique can measure many different drugs in a small sample volume. While some older studies used saliva but had many analytical problems (including an insufficient sample volume in up to a third of the cases), newer methods of saliva sampling and analysis give better results. The use of saliva for roadside surveys allows non-invasive sampling, but the lack of correlation with the concentrations in blood makes interpretation of results difficult.The results of both epidemiological and experimental studies should be combined to obtain a good estimate of the impact of certain drugs on driving performance and accident risk. In 2006–07 a committee of international experts drafted guidelines for future research into drugs and driving. These have been taken on board by the DRUID project, a large-scale EU funded project on driving under the influence of drugs, alcohol and medicines.     

Hair analysis for cocaine: factors in laboratory contamination studies and their relevance to proficiency sample preparation and hair testing practices

Since the introduction in 2001 of a urine-based detection method for recombinant erythropoietin (rHuEPO), transfusion-doping practices have regained interest. To address this problem, an efficient antidoping test designed to obtain direct proof of allogeneic blood transfusion was developed and validated. This test, based on flow cytometry analysis of red blood cell (RBCs) phenotypes, was used to determine the absence or the presence of numerous RBCs populations in a blood sample. A such, it may constitute a direct proof of an abnormal blood population resulting from homologous transfusion. Single-blind and single-site studies were carried out to validate this method as a forensic quality standard analysis and to allow objective interpretation of real cases. The analysis of 140 blood samples containing different percentages (0-5%) of a minor RBCs population were carried on by four independent analysts. Robustness, sensitivity, specificity, precision and stability were assessed. ISO-accredited controls samples were used to demonstrate that the method was robust, stable and precise. No false positive results were observed, resulting in a 100% specificity of the method. Most samples containing a 1.5% minor RBCs population were unambiguously detected, yielding a 78.1% sensitivity. These samples mimicked blood collected from an athlete 3 months after a homologous blood transfusion event where 10% of the total RBCs present in the recipient originated in the donor. The observed false negative results could be explained by differences in antigen expression between the donor and the recipient. False negatives were more numerous with smaller minor RBCs populations. The method described here fulfils the ISO-17025 accreditation and validation requirements. The controls and the methodology are solid enough to determine with certainty whether a sample contains one or more RBCs populations. This variable is currently the best indicator for homologous blood transfusion doping.     

Ethyl glucuronide: unusual distribution between head hair and pubic hair

Ethyl glucuronide (EtG) is a minor metabolite of ethanol that can be detected in hair. In some specific situations, head hair can be missing, and therefore, alternative anatomical locations of hair are of interest. In this study, paired hair specimens (head hair and pubic hair) from eight social drinkers were analyzed for EtG. Each sample was decontaminated by two dichloromethane bathes (5 ml) for 2 min. After cutting into small pieces, about 50 mg of hair was incubated in 2 ml water in the presence of 10 ng of EtG-d5, used as internal standard and submitted to ultra-sonication for 2 h. The aqueous phase was extracted by SPE using Oasis MAX columns. The hair extract was separated on an ACQUITY BEH HILIC column using a gradient of acetonitrile and formate buffer. Detection was based on two daughter ions: transitions m/z 221-85 and 75 and m/z 226-75 for EtG and the IS, respectively. This laboratory is using a positive cut-off at 50 pg/mg. All eight head hair specimens were negative for EtG at a limit of quantitation fixed at 10 pg/mg. Surprisingly, EtG was identified at high concentrations in pubic hair, in the range 12-1370 pg/mg. It appears, therefore, that it is not possible to document the drinking status of a subject by simply switching from head hair to pubic hair.     

C/S、B/S结构相结合的公安院校远程招生系统设计

本文提出了建立基于C/S、B/S体系结构相结合的公安院校远程招生系统,给出了总体设计方案,包括系统结构、系统模块功能和数据库表结构,提出了系统设计的原则,介绍了系统所采用的软件平台和所使用的基本技术。     

A TLC visualisation reagent for dimethylamphetamine and other abused tertiary amines

Application of citric acid/acetic anhydride reagent (CAR), a colour reagent selective for tertiary amines in solution, improves detection of abused tertiary amino drugs on the TLC plate. The plate is pretreated by a brief immersion in phosphoric acid/acetone solution to suppress colouration. After suppressing, the plate is sprayed with CAR and heated at 100 degrees C, causing tertiary amines to turn red purple within 3 minutes. The sensitivity of this new CAR method is 2.5 to 15-times greater than that of conventional detection with Dragendorff reagent for some of the tertiary amines dimethylamphetamine, methylephedrine, levomepromazine, chlorpromazine, caffeine, theophylline, theobromine and nicotine. This present method provides rapid TLC detection of abused tertiary amino drugs such as phenethylamine, phenothiazine, xanthine derivative, nicotine and narcotics.