ABSTRACT
A method for the determination of methylmercury in seafood has been developed using dispersive liquid-liquid microextraction followed by direct mercury analyzer. Total mercury was detected by direct mercury analyzer, and inorganic mercury was calculated by the difference. The parameters affecting the extraction efficiency, including the selection of extractant and dispersant, their volume ratio, concentration of HCl and NaCl have been optimized in this study. The results showed that CH2 Cl2 as extractant, ethanol as dispersant, Volume ration of 1:5, 1 mol/L HCl and 120 g/L NaCl were chosen. The detection limit and the dynamic liner range were 0. 10 μg/L and 0. 2-20 μg/L, respectively. The relative standard deviation was 6. 0% for eleven replicates at the spiked level of 2. 0 μg/L. The enrichment factor was 8. For total Hg determination, the detection limit and the dynamic liner range for methylmercury were 0. 10 μg/kg and 0. 2-50 μg/kg, respectively. The relative standard deviation was 2. 4%. The method was simple, fast and a little solvent needed. Some certified reference materials were analyzed to validate the accuracy of the proposed method, and the results were in good agreement with the reference value. Besides, the method was applied to the real samples with satisfactory results.
ABSTRACT
Objective To evaluate the angiographic findings and the therapeutic effect of thrombolysis in AMI (acute myocardial infarction) patients. Method A retrospective study were carried out in consecutive eighty-four inpatients with AMI treated with intravenous thrombolysis and coronary angiography was taken within a week after illness onset from January 2000 to August 2007. The patients were divided into successful recanalization group and non-recanalization group. Single factor χ2 test and multi-factor logistic regression analysis were applied to observe the relationship among the angiographic features of IRA (infarct-related artery including the number of stnosis, the location of stenosis, the severity of stenosis and the morphological changes) and treatment effect of intravenous urokinase thrombolysis. Results (1) Single factor χ2 test showed that location and the extent of lesion of IRA were eligible to enter the logistic regression formula (P ＜ 0.05),whereas the number of lesions and the severity of IRA's stenosis were not eligible to enter the logistic regression formula (P ＞ 0. 05). (2) Multi-factor logistic regression analysis showed that the extent of lesion of IRA was the only factor that had a negative impact on the therapeutic effect of intravenous thrombolysis.Conclusions The study shows that the extent of lesion of IRA is the only factor that has a negative impact on the therapeutic effect of intravenous thrombolysis; The number, the location of lesion and the severity of stenosis of IRA have no impact on the therapeutic effect of intravenous thrombolysis in AMI.