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261.
A 27-year-old man was carrying in his digestive tract 99 packages each containing about 10 g of a 86% cocaine powder. The courier died by acute cocaine intoxication due to inflation and rupture of four packages during a flight from Bogotá to Rome. At the autopsy, the external examination was unremarkable. The internal examination showed edema and generalized congestion of the organs. Toxicological analyses were performed by gas chromatography-mass spectrometry after solid phase extraction using Bond Elut Certify columns and derivatization with BSTFA/TMCS. High levels of cocaine and benzoylecgonine were found in blood (4.0 microg/mL and 17.0 microg/mL), urine (152.0 microg/mL and 512.0 microg/mL), bile (99.8 microg/mL and 54.0 microg/mL), vitreous humor (7.1 microg/mL and 5.8 microg/mL), brain (7.5 microg/mL and 3.5 microg/mL), and hair (55.5 ng/mg and 27.7 ng/mg). The presence of the cocaine and its metabolite in the hair suggested that the man was a cocaine user.  相似文献   
262.
Glycated hemoglobin (HbA(1c)) has been demonstrated to be a useful marker for long-term glucose control in diabetes. This parameter characterizes each non-enzymatic fixation of glucose on hemoglobin. It is a useful test in addition to periodic glycemia controls since it reflects the mean glycemia of the past 60 days. We studied the conservation of HbA(1c) at 4 degrees C as a function of time with different anti-coagulants and preservatives (3, 6 months, 1 year). A total of 106 tests were performed using the high performance liquid chromatography (HPLC) method dedicated to the semi-automatic analysis of HbA(1c) (Bio-Rad) and we applied the method in forensic cases. Conservation at 4 degrees C was good for as long as 3 months in blood samples collected with fluoride and 6 months in samples collected in a dry or in a heparinized tube. In non-diabetic subjects, HbA(1c) reference values obtained from forensic samples were identical to those of living controls (3.5-6.25% of total hemoglobin). All positive HbA(1c) results were confirmed by a medical evaluation. This method was successfully applied to five forensic cases. In cases of increased acetonemia, acetone or isopropanol are easily measured. However, in some unexplained post-mortem circumstances, increased HbA(1c) permits to differentiate alcoholic or starvation ketoacidosis from the diabetic cases. Glycated hemoglobin should, therefore, be considered the forensic marker of choice in the post-mortem diagnosis of a diabetic disorder and demonstrates its usefulness in post-mortem validation.  相似文献   
263.
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.  相似文献   
264.
The study was performed to distinguish fatal from non-fatal blood concentrations of morphine. For this purpose, blood levels of free morphine and total morphine (free morphine plus morphine conjugates) in 207 cases of heroin-related deaths were compared to those in 27 drivers surviving opiate intoxication. The majority of both survivors and non-survivors were found to show a concomitant use of depressants including alcohol or stimulants. Blood morphine levels in both groups varied widely, with a large area of overlap between survivors (free morphine: 0-128 ng/ml, total morphine: 10-2,110 ng/ml) and non-survivors (free morphine: 0-2,800 ng/ml, total morphine: 33-5,000 ng/ml). Five (18.5%) survivors and 87 (42.0%) non-survivors exhibit intoxication only by morphine. In these cases, too, both groups overlapped (survivors-free morphine: 28-93 ng/ml, total morphine: 230-1,451 ng/ml; non-survivors-free morphine: 0-2,800 ng/ml, total morphine: 119-4,660 ng/ml). Although the blood levels of free or total morphine do not allow a reliable prediction of survival versus non-survival, the ratio of free/total morphine may be a criterion to distinguish lethal versus survived intoxication. The mean of the ratio of free to total morphine for all lethal cases (N=207) was 0.293, for those that survived (N=27) 0.135, in cases of intoxication only by morphine 0.250 (N=87) and 0.080 (N=5), respectively. Applying a cut-off of 0.12 for free/total morphine and performing ROC analyses, fatal outcome can be predicted in 80% of the cases correctly, whereas 16% of the survivors were classified as dead. Nevertheless, in this study, all cases with a blood concentration of 200 ng/ml and more of free morphine displayed a fatal outcome.  相似文献   
265.
本文评述了美国与东亚大国———中国、日本、俄罗斯、印度及东盟的关系,以及这些关系对东亚的影响,并着重分析了中国与东亚大国的关系。作者认为,中美关系肯定是未来东亚地区最重要的战略关系。中国的崛起促使创立东亚地区机制成为必要。多边合作是解决和克服双边低效的最直接的战略,因此,创立东亚共同体的想法具有很重要的意义。  相似文献   
266.
应暨南大学的邀请,2006年5月27-30日,印尼前国家领导人———印尼人民协商会议(MPR)主席、印尼国民使命党前任总主席、穆罕默迪亚前任总主席、现印尼国民使命党荣誉主席、印尼知名学者阿敏.赖斯教授(Prof.Dr.HM Amien Rais)对暨南大学进行了为期3天的学术访问,并被聘请为暨南大学客座教授。期间,阿敏.赖斯教授做了两场学术报告,分别就印尼民主化进程、中国印尼关系、国际形势等诸多问题发表了看法。参加学术报告会的有暨南大学东南亚研究所暨国际关系学系师生、印尼留学生、广东外语外贸大学印尼语专业师生和广州市、中山市、珠海市的印尼归侨代表等130人,东南亚研究所所长曹云华教授主持了学术报告会。现对其主要观点和看法进行整理,以飨广大  相似文献   
267.
环境对学习语言非常重要,充分利用社会大环境,创造良好的课堂小环境,发挥学生自然习得的作用,建立课堂教学与自然习得相结合的新教学体系,这是提高教学效果的重要途径。  相似文献   
268.
上海合作组织五周年宣言   总被引:1,自引:0,他引:1  
值此上海合作组织(以下简称“本组织”)成立5周年之际,本组织成员国元首——哈萨克斯坦共和国总统纳扎尔巴耶夫、中华人民共和国主席胡锦涛、吉尔吉斯共和国总统巴基耶夫、俄罗斯联邦总统普京、塔吉克斯坦共和国总统拉赫莫诺夫、乌兹别克斯坦共和国总统卡里莫夫在本组织诞生地——上海举行会议,声明如下:  相似文献   
269.
贫国与富国:基于治理理论的解释   总被引:1,自引:0,他引:1  
本文通过对荷兰与加纳、新加坡与牙买加、日本与尼日利亚等几组国家进行比较研究,指出国家贫富差别的主要原因在于治理,而非资源。  相似文献   
270.
规则与规则制定是美国联邦行政程序法中确定的一个重要的政府规制工具,本文对规则制定的发展史作了一个简要的回顾,对其实施过程中产生的问题作了分析与评估,并对其未来发展以及行政程序法的实施作了展望,对于我们了解规则制定与美国联邦行政程序法具有较大的作用。  相似文献   
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