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61.
GC/ECD检验生物检材中的氟乙酸钠   总被引:4,自引:1,他引:3  
建立对生物检材中氟乙酸钠的GC/ECD检验方法。用PFBBr作衍生化试剂,对氟乙酸钠或氟乙酰胺中毒后脏器中的氯乙酸(氯乙酸钠)进行衍生化,GC/ECD和GC/MS的分析。在1ml血中添加lμg1080,其回收率为76.2%,RSD为3.07(n=7);在1g肝中添加2μg的1080其回收率为84.4%,RSD为1.87(n=5)。研究的方法经动物试验和大量中毒案件的验证,效果较好。该方法已在中毒案件的检验中广泛应用。  相似文献   
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63.
This paper argues that the Chinese government’s ‘belt and road’ initiative – the Silk Roads vision of land and maritime logistics and communications networks connecting Asia, Europe and Africa – has its roots in sub-national ideas and practices, and that it reflects their elevation to the national level more than the creation of substantially new policy content. Further, the spatial paradigms inherent in the Silk Roads vision reveal the reproduction of capitalist developmental ideas expressed particularly in the form of networks, which themselves have become a feature of contemporary global political economy. In other words, the Silk Roads vision is more of a ‘spatial fix’ than a geopolitical manoeuvre.  相似文献   
64.
在国际学术界和国际政治领域,俄罗斯问题是一个很复杂的概念.之所以如此,远不只是俄国本身的文明结构之复杂性所致,更有西方的独特表述之原因.影响西方对俄罗斯问题表述的,是因为西方自身的欧洲中心论、欧美所建构的"西方"概念及其在国际和俄国所产生的反应、对俄罗斯问题进行斯拉夫-俄国-苏联学研究等,这些原因从不同方面促成了西方对俄罗斯问题的认知和判断远不同于俄国,既时有谬误,又始终有着主体意识、独特发现.  相似文献   
65.
作为地区研究层次的两个变量,地区主义与地区秩序之间有着不可分割的内在联系。地区主义的产生与发展,很大程度上源于国家的自愿选择与共识,这种运行方式维护了地区所有成员的利益,从本质上保证了地区秩序的有效性、合法性和持久性。从地区发展的实践来看,构建地区秩序的模式主要有外源强制型、内源强制型、外源合作型和内源合作型四种。地区主义的发展改变了地区各政治实体之间的互动关系,通过价值观念与地区认同、地区制度以及地区主义的政治经济影响等因素促使地区秩序逐步从外源强制型向内源合作型演进。  相似文献   
66.
The status of international agricultural research as a global public good (GPG) has been widely accepted since the Green Revolution of the 1960s and 1970s. While the term was not used at the time of its creation, the Consultative Group on International Agricultural Research (CGIAR) system that evolved at that time has been described as a ‘prime example of the promise, performance and perils of an international approach to providing GPGs’. Contemporary literature on international agricultural research as a GPG tends to support this view and focuses on how to operationalize the concept. This paper adopts a different starting point and questions this conceptualization of the CGIAR and its outputs. It questions the appropriateness of such a ‘neutral’ concept to a system born of the imperatives of Cold War geopolitics, and shaped by a history of attempts to secure its relevance in a changing world. This paper draws on a multi-sited, ethnographic study of a research effort highlighted by the CGIAR as an exemplar of GPG-oriented research. Behind the ubiquitous language of GPGs, ‘partnership’ and ‘consensus’, however, new forms of exclusion and restriction are emerging within everyday practice, reproducing North–South inequalities and undermining the ability of these programmes to respond to the needs of projected beneficiaries.  相似文献   
67.
This special issue should go a long way towards increasing the understanding of Peirce’s semeiotic and its applicability for solving problems in legal studies. In fact, the New Science of Semiotics should result in developing a rigorous and systematic methodology for legal studies making it a true semiotic science which I suggest calling “jurisology.”  相似文献   
68.
Since 1960, it has been demonstrated by various analytical procedures that high concentrations of arsenic were present in Napoleon's hair. Various authors, indicating that the detected arsenic levels are a consequence of external contamination, have challenged the results of these examinations. We have tested two strands of hair, referenced as Noverraz and Grand Maréchal Bertrand. Samples were incubated 6 h in water at 90 °C, and arsenic speciation was carried out by HPLC–ICP/MS. The residue was injected on a cation-exchange PRP-X200 column that allows the detection of arsenobetaine and on an anion-exchange PRP-X100 column to test for the mineral forms. In these conditions, the inorganic species As(III), As(V) and their metabolites (DMA and MMA) were separated. Analysis of hair samples highlighted massive amounts of total arsenic (42.1 and 37.4 ng/mg). Arsenical species found in the two samples of analyzed hair are distributed in the following: As(III) 31.1 and 44.7%; As(V) 66.3 and 53.2%; DMA 0.42 and 0.15%. Traces of MMA were detected, and 2% of the species could not be identified. These results prove that more than 97% of the arsenic found in the hair of Napoleon is in inorganic form, which is consistent with a chronic intoxication to arsenic.  相似文献   
69.
A rapid and sensitive method using LC-MS/MS triple stage quadrupole for the determination of traces of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, “ecstasy”), 3,4-methylenedioxyethamphetamine (MDEA), and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair, blood and urine has been developed and validated. Chromatography was carried out on an Uptisphere ODB C18 5 μm, 2.1 mm × 150 mm column (Interchim, France) with a gradient of acetonitrile and formate 2 mM pH 3.0 buffer. Urine and blood were extracted with Toxitube A® (Varian, France). Segmented scalp hair was treated by incubation 15 min at 80 °C in NaOH 1 M before liquid–liquid extraction with hexane/ethyl acetate (2/1, v/v). The limits of quantification (LOQ) in blood and urine were at 0.1 ng/mL for all analytes. In hair, LOQ was <5 pg/mg for MA, MDMA, MDEA and MBDB, at 14.7 pg/mg for AP and 15.7 pg/mg for MDA. Calibration curves were linear in the range 0.1–50 ng/mL in blood and urine; in the range 5–500 pg/mg for MA, MDMA, MDEA and MBDB, and 20–500 pg/mg for AP and MDA. Inter-day precisions were <13% for all analytes in all matrices. Accuracy was <20% in blood and urine at 1 and 50 ng/mL and <10% in hair at 20 and 250 pg/mg. This method was applied to the determination of MDMA in a forensic case of single administration of ecstasy to a 16-year-old female without her knowledge during a party. She suffered from hyperactivity, sweating and agitation. A first sample of urine was collected a few hours after (T + 12 h) and tested positive to amphetamines by immunoassay by a clinical laboratory. Blood and urine were sampled for forensic purposes at day 8 (D + 8) and scalp hair at day 60 (D + 60). No MDMA was detected in blood, but urine and hair were tested positive, respectively at 0.42 ng/mL and at 22 pg/mg in hair only in the segment corresponding to the period of the offence, while no MDA was detectable. This method allows the detection of MDMA up to 8 days in urine after single intake.  相似文献   
70.
目的研究甲基苯丙胺及其代谢物苯丙胺在家兔体内的毒物代谢动力学行为。方法GC/MS法测定家兔灌胃甲基苯丙胺后不同时间点血、尿中甲基苯丙胺和代谢物苯丙胺浓度,采用3P97程序进行房室模型拟合以及毒物代谢动力学参数计算。结果甲基苯丙胺和苯丙胺在家兔体内的毒物代谢动力学过程均呈一级动力学特征,符合二室开放模型。甲基苯丙胺在家兔体内Cm ax为1.457 mg/L±0.094 mg/L,Tm ax为1.557h±0.078h,t1/2 ka、t1/2α和t1/2β分别为0.384h±0.052h、1.614h±0.036h和3.007h±0.430h,CL为1.769 L/h/kg±0.114 L/h/kg。甲基苯丙胺的毒物代谢动力学方程为:C t=2.767 e-0.746 t+1.454 e-0.234 t+4.119 e-1.746 t。结论甲基苯丙胺在家兔体内吸收、消除和代谢都较快。建立的甲基苯丙胺毒物代谢动力学方程和参数可为甲基苯丙胺分析的合理取样、从血药浓度推断服毒时间以及甲基苯丙胺滥用的法医学鉴定提供理论依据。  相似文献   
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