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1.
A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning.  相似文献   
2.
In a case of suicidal application of electricity differences between the rectal temperature of the body and the suspected time of death were observed.In order to answer the question whether an electric current from hand to hand over >30 min led to a rise in body temperature FEM-based computer simulations and animal experiments were carried out. Both resulted in a warming of the soft parts in the arm without warming the body core. Thus a temperature-based estimation of the time since death can also be used in cases with electricity as the cause of death. Besides, in the animal experiment we found a spontaneous rise in the body core temperature even without application of electricity which may be a reason for the typical temperature plateau after death.  相似文献   
3.
Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept® oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept® enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall ‘present’/‘not found’ reports calculated as true positives/(true positives + false negatives) were for the amfetamine specific assay 50%, methyl-amfetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques.  相似文献   
4.
This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.  相似文献   
5.
An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm3, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H+], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d3-THC + H+]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r2 = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette® collection, 26 of the 40 cases had an undetectable THC.  相似文献   
6.
中国现行侦检关系受制于线型诉讼结构,存在诸多弊端而有待完善。但是,“侦检一体化”模式不符合中国侦检关系模式的设置,不具备实践可行性。对此,应当加强检察机关对侦查活动的监督、制约,并且对于拒绝监督与制约的,予以惩戒。同时增强辩方力量,实现审前程序控辩平衡。  相似文献   
7.
Classroom The increased use of information technology in schools is generally perceived as a positive, dynamic step into the future. By providing IT facilities for all children throughout their education we are affording them access to a wider range of career opportunities and educational experiences. Feminists have long debated the extent to which technology can be exclusionary for women because of its construction as a masculine domain, emphasizing 'masculine' characteristics of mastery, skill and control. By focusing on the music classroom, Armstrong explores gender and the compositional process and the effects of an overtly technological approach to composition. In the early part of the essay, she draws on Sherry Turkle's early work based on observations of male and female computer programmers. Despite observing a variety of computational styles Turkle concluded that, although technology allowed for this diversity, computer culture did not, noting that many females preferred a style that did not favour the canonical, plan-oriented, abstract thinkers who 'constitute an epistemological elite'. In her own research, Armstrong found that girls often became alienated from their own creative work because the culture of the music classroom appears to privilege a particular style of working. By focusing on the singing voice and the corporeal, Armstrong draws on aspects of cyberfeminism to illustrate how girls can transcend and subvert this masculine culture.  相似文献   
8.
检测体液中氰含量的荧光光度法研究   总被引:1,自引:2,他引:1  
本文报道了应用取代反应检测体液中氰含量的荧光光度法。探讨了检测的具体方法和有关条件对检测的影响。检测了正常人血、尿液和唾液中氰含量,并检测了小鼠氰化物染毒死亡后血中氰含量。研究表明,本法不但可检测体液中致死量的氰化物含量,亦可检测体液中正常氰含量。  相似文献   
9.
乡土秩序的失落——对流动人口犯罪的社会学思考   总被引:1,自引:0,他引:1  
流动人口犯罪的原因及其防治机制不能从流动人口群体以外的范围内去寻找 ,必须深入到生成流动人口的具体社会结构中去探寻。该社会结构主要有二方面要素 :城乡二元格局 ;户籍管理体制和现存的庞大剩余劳动力。流动人口犯罪的基础性原因是存在于流动人口群体中的乡土秩序在城市中的失落 ,以及由此而产生的流动人口生存与发展预期的落空。要解决这些问题 ,必须寻找一个重建秩序之路 ,也就是经过小城镇化而达到全面的城市化。其目标是消除两种秩序的差别和对立 ,直至建立最大限度遏制流动人口犯罪的新型秩序。  相似文献   
10.
本实验应用单克隆抗人精子抗体和酶标记羊抗人精子抗体,采用ELISA方法确定精子抗原成份的存在。对10份新鲜精液,15份精斑进行了验测,其结果阳性率为100%。新鲜精液(精子数约10,000万个/ml)稀释100万倍,精斑浸出液稀释50万倍,均可出现阳性。对唾液斑、尿斑、乳汁斑、阴道斑、汗斑及输精管结扎的精液均为阴性。实验结果表明,本法检验精子抗原具有灵敏度高,特异性好的优点。  相似文献   
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