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131.
Tarek Belal Tamer Awad Jack DeRuiter C. Randall Clark 《Forensic Science International Supplement Series》2008,178(1):61-82
A series of side chain regioisomers of 3-methoxy-4-methyl- and 4-methoxy-4-methyl-phenethylamines have mass spectra essentially equivalent to the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA), all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. The acetyl, propionyl and trifluoroacetyl derivatives of the primary and secondary regioisomeric amines were prepared and evaluated in GC–MS studies. The mass spectra for these derivatives were significantly individualized and the resulting unique fragment ions allowed for specific side chain identification. The trifluoroacetyl derivatives provided more fragment ions for molecular individualization among these regioisomeric substances. These trifluoroacetyl derivatives showed excellent resolution on a non-polar stationary phase such as Rtx-1. 相似文献
132.
This study is an extension of a previous evaluation of a program (Red Flag/Green Flag) in which children, parents, and teachers were exposed to a workbook and film designed to teach personal safety strategies for preventing sexual victimization or encouraging adult assistance through disclosure of such incidents. In the current investigation, only children and their teachers received this didactic training program. Children and teachers from neighboring schools were assigned to a Training or Control group. Self-reports from children, teachers, and parents, as well as guidance counselor incident reports, were obtained to evaluate outcome. Results indicated greater gains in general knowledge and prevention skills at post-training and 6-month follow-up for trained than control children. Some improvements were made by trained teachers and parents of trained children. Child reports of personal experiences and guidance counselor incident reports were in accord with the assistance component of the program. However, the pattern of reports across sources is difficult to interpret. The findings are discussed in light of salient issues regarding the content of training, child disclosure, and methodology. 相似文献
133.
采用RT-PCR方法对1株H9N2亚型禽流感病毒Ck/GS/2/99株RNA聚合酶基因PB2、PB1和PA分别进行了扩增,将其克隆到pGEM-T easy载体后进行序列测定与分析。结果表明,该株病毒的PB2、PB1和PA基因开放阅读框(ORF)分别由2280、2274和2 151个碱基组成,分别编码759、757和716个氨基酸。经同源性与系统发生树分析,该毒株RNA聚合酶基因PB2、PB1和PA与Ck/NX/4/99株的核苷酸和氨基酸同源性均在98%以上,另外这3个基因与Dk/HK/Y280/97、Sw/HK/9/98和Qu/HK/NT/28/99株的关系密切。 相似文献
134.
Kim English 《Journal of Quantitative Criminology》1993,9(4):357-382
This paper presents findings from the first study of female prisoners' self-reports of criminal activity. Using the criminal career paradigm to frame the analysis, self-reported estimates of crime participation and frequency rates were examined for eight felony crimes. Important similarities between women and men were found in overall patterns of crime. Specifically, a small proportion ofboth women and men described committing a large portion of the total crimes reported. These data also suggest that women and men are similar in violent crime participation — a finding that varies from the current literature. Once active in a crime type, women and men committed assault, theft, and forgery at significantly different rates; no gender differences were found in the annualized frequency rates of burglary, robbery, motor vehicle theft, fraud, and drug dealing. However, although statistical differences were not found in the overall frequency of drug dealing, specific patterns of drug dealing reflected considerable gender variation, with a larger proportion of the female sample committing very frequent (daily) drug dealing activity. The findings reflect the value of the criminal career paradigm for the study of gender differences. Future research should include largescale quantitative designs that allow detailed analyses of correlates of the distinct criminal career dimensions.Points of view are those of the author and do not necessarily reflect the official position of the U.S. Department of Justice.This research was funded in part by the National Institute of Justice, Grant 87-IJ-CX-0048. 相似文献
135.
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
136.
POPULATION: Population: Illinois Caucasian ( n =117), Illinois African American ( n =218), and Illinois Hispanic ( n =68). 相似文献
137.
138.
Eiichi Mikami Tsutomu Ohno Hiroshi Matsumoto 《Forensic Science International Supplement Series》2002,130(2-3):140-146
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
139.
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
140.