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881.
882.
A rapid and accurate method, combining solid-phase extraction and second-order derivative spectrophotomety approaches, is developed for the simultaneous determination of diquat (DQ) and paraquat (PQ) in blood, tissue and urine samples. Supernatant resulting from the precipitation of protein (with trichloroacetic acid) in plasma and tissue or Amberlite IRA-401 resin treated urine are passed through a mini-column packed with Wakogel gel (Silica gel). Analytes are then eluted with a non-organic solvent, 0.2mol/l HCl solution containing 2mol/l NH(4)Cl. UV spectrum of the eluent in 220-350nm range provides effective screen to detect the presence of DQ and/or PQ. In the presence of DQ or PQ alone, the analyte present is quantitated by conventional zero- or second-order derivative spectrophotometry. The calibration curve in the 0.1-5.0mg/l range for either analyte obeys Beer's law. When both DQ and PQ are present, their concentrations are determined by the peak amplitudes of their respective second-derivative spectra after the addition of alkaline dithionite reagent. Interference is negligible when the DQ/PQ concentration ratio is within the 5.0-0.2 range.Using a 2-ml of sample size, the detection limits for DQ and PQ in plasma are 0.02 and 0.005mg/l. The corresponding detection limits for urine samples (10ml sample size) are 0.004 and 0.001mg/l. Recoveries of DQ and PQ in triplicate plasma and urine samples spiked with 0.5mg/l of analytes are 93 and 85%. The precision of the proposed method resulting from triplicate study of spiked urine samples varies from 3.2 to 4.6% at 0.5mg/l of DQ and PQ, respectively.  相似文献   
883.
Allele frequencies for the eight STRs included in the GenePrint PowerPlex 1.2 kit were obtained from three population groups that are resident in the United Arab Emirates (UAE); 228 unrelated UAE individuals, 194 unrelated Indian individuals and 197 unrelated Pakistani individuals were analysed.  相似文献   
884.
885.
886.
This study uses longitudinal data to identify risk markers for reassault among batterer program participants. Data are from 308 men and their partners collected at five, 3-month intervals. Time-varying situational and behavioral risk factors, as well as time-invariant individual characteristics, are examined. The most influential risk markers, in terms of relative risk and level of statistical significance, were time-varying: 2 measures of the man's drunkenness during the follow-up interval in which the reassault occurred (OR: 3.5-16.3; p > .0005). Other included time-varying batterer characteristics had no significant effect on reassault. Two significant time-invariant batterer risk factors were (1) severe psychopathology and (2) a history of non-domestic-violence arrest, both measured at intake. Results suggest that batterers' drinking behavior after program intake may provide an important and easily observed marker for risk of reassault and that prediction of reassault with individual risk factors at program intake remains problematical.  相似文献   
887.
888.
Almost all European countries are member countries of Interpol, the World Customs Organisation and the United Nations. Some of them are Benelux and Schengen countries, and 15 are EU Member States. With this in mind, Europe can be considered, in policing terms, as being made up of a series of concentric and overlapping circles. The map shows overlapping institutional sources, territorial remits, functional specialisations and strategic emphasis. This article focuses on recent developments in European police co-operation, as well as judicial co-operation. International law enforcement co-operation is more and more influenced by basic political developments. Based on a rather complex, and sometimes confusing patchwork of institutions, there is a growing influence of intergovernmental based new developments. In particular prevention and combating organised crime are the main reasons for new and more professional ways of improved horizontal co-operation.  相似文献   
889.
家兔死后眼玻璃体液锌、镍含量与 PMI关系的研究   总被引:6,自引:3,他引:3  
Gong ZQ  Xu XM  Zeng XB  Sun YG  Wang DW 《法医学杂志》2001,17(3):129-131
目的寻找一种精确推定PMI的方法。方法应用电感耦合等离子体质谱(ICP-MS),检测了家兔死后96小时内眼玻璃体液锌、镍元素含量,探讨其与PMI的相关性。结果家兔死后24h内眼玻璃体液锌、镍元素含量与PMI显著相关,可作为推定早期PMI的参考指标,其二项式回归方程分别为y=0.1404x2-1.3351x+3.8298(R2=0.9202)、y=0.0043x2-0.0596x+0.2665(R2=0.9103)。结论家兔眼玻璃体液中Zn、Ni元素含量变化是推定早期PMI的参考指标之一。  相似文献   
890.
线粒体 DNA突变与心肌病关系的研究进展   总被引:1,自引:0,他引:1  
Lu JJ  Lu HL 《法医学杂志》2001,17(4):242-243
人类某些疾病与线粒体DNA(mtDNA)基因组缺陷有关.本文就mtDNA突变与缺血性心肌病和肥厚型心肌病关系的研究加以回顾.目前的研究大多认为心肌缺血缺氧致氧化磷酸化紊乱,产生氧自由基损伤mtDNA,以及缺氧致氧化磷酸化过度诱导而损伤mtDNA,慢性损伤积累终致mtDNA片断缺失或点突变,主要表现出mtDNA5.0kb、7.4kb缺失及细胞色素b(cytb)基因上C15452A点突变;tRNA基因保守序列突变,致肌肉收缩蛋白合成缺陷,缺陷的收缩蛋白持续而无效的收缩可能会增加心肌对ATP的代谢需求,因此导致心肌肥厚.  相似文献   
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