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131.
本文研究了一种同时测定生物样品中二氯苯醚菊酯、氯氰菊酯、杀火菊酯、溴氰菊酯的方法,并详细介绍了试管提取净化的过程。在安装电子捕获检测器的气相色谱仪上,选择不同极性的色谱柱和优选操作参数,能使上述4种杀虫剂达到基线分离,并在20~25分钟内同时完成分析。添加生物样品肝、胃,脑、血中的回收率达到70~90%;变异系数在±0.03~0.08范围。应用本文建立的方法,对中毒兔(溴氰菊酯和杀灭菊酯)各脏器均检出了原体杀虫剂,并成功地运用于一些法庭中毒案件的鉴定。  相似文献   
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POPULATION: Population: Illinois Caucasian ( n =117), Illinois African American ( n =218), and Illinois Hispanic ( n =68).  相似文献   
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An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography–mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F254 plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm×150 mm, 5 μm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.  相似文献   
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This paper deals with the police officer's or police doctor's ability to find drivers under the influence of drugs. We have also studied whether the protocol on the driver's previous histories of drug intake is useful for directing the chemist in his analytical approach to revealing intoxicants in the suspects' body fluids. A comprehensive procedure for screening traffic-hazardous drugs in the urine was found necessary and is described. By using this method, we have studied the incidence of drunken drivers with detectable medicinal or illicit agents. The results demonstrate that 91% of those drivers found by the officer or doctor of the police to be on intoxicants other than ethanol, carried some kind of traffic-hazardous drug in their body fluids, and that the doctor was a better judge than the police in identifying these offenders. By using a series of chemical methods for drug screening, we found that every third driver suspected of drunken driving due to ethanol, but not to other intoxicants, held some kind of a traffic-hazardous drug substance in his urine; benzodiazepines and cannabinoids were the most common findings. The data imply that 34% of these suspects revealed their intakes of traffic-dangerous intoxicants. We conclude that the judgements of both the officer and doctor of the police are needed for an efficacious detection of drivers under the influence of drugs. Moreover, the results infer that the chemist has to screen for intoxicants to reveal these in a suspect driver. We also conclude that drugs, particularly the benzodiazepines or cannabinoids, may be commonly encountered in drunken drivers, suspected of being inebriated by ethanol but no other toxicants.  相似文献   
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Yan H  Xiang P  Bo J  Shen M 《法医学杂志》2007,23(6):441-443
目的建立测定血液中美西律(mexiletine)的液相色谱-串联质谱联用法(LC-MS/MS)。方法采用简便的乙腈蛋白沉淀法对血液进行预处理,应用Allure PFP Propyl液相柱分离,用电喷雾正离子模式离子化,多反应监测模式对美西律进行分析。结果美西律与内标纳洛酮分离良好,在0.02~10.00μg/mL内线性关系良好,相关系数为0.9999,回归方程为y=0.0283x-0.0151,日内与日间精密度的RSD均小于15%,最低检测限为0.01μg/mL。结论建立的LC-MS/MS方法简单、灵敏、可靠,可同时适用于美西律临床药物监测和法医毒物分析的需要。  相似文献   
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Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators.  相似文献   
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