The widespread use of organophosphorus pesticides(OPs) poses a great threat to human health and has made the detection of OP residues in food an important task,especially in view of the fact that easy and rapid detect...The widespread use of organophosphorus pesticides(OPs) poses a great threat to human health and has made the detection of OP residues in food an important task,especially in view of the fact that easy and rapid detection methods are needed.Because OPs have inhibitory effects on the activity of α-naphthyl acetate esterase(ANAE) in plants,in this work we evaluated the possibility of detecting OPs in vegetables with ANAE extracted from commercial flour.The limits of detection(LODs) obtained for methamidophos,dichlorvos,phoxim,dimethoate,and malathion in lettuce samples with crude ANAE were 0.17,0.11,0.11,0.96,and 1.70 mg/kg,respectively.Based on the maximum residue limits(MRLs) for OPs in food stipulated by Chinese laws which are 0.05,0.20,0.05,1.00,and 8.00 mg/kg for methamidophos,dichlorvos,phoxim,dimethoate,and malathion,respectively,the esterase inhibition method with crude ANAE had sufficient sensitivity to detect the residues of dichlorvos,dimethoate,and malathion in lettuce,but it could not be used to guarantee the safety of the same samples if methamidophos or phoxim residue was present.The sensitivity of the method was improved by the use of esterase purified by ammonium sulfate salting-out.The LODs obtained for methamidophos and phoxim with purified esterase were lower than the MRLs for these OPs in food.This is a very promising method for the detection of OP residues in vegetables using crude or purified esterase because of its cheapness,sensitivity,and convenience.展开更多
通过对我院抗白血病有效方剂益气养阴方和补气养血方进行免疫功能测定,发现二方既可显著提高T淋巴细胞酸性非特异性酯酶染色(AN A E)阳性率(前者P<0.05,后者P<0.01),又可显著提高粒细胞吞噬率及吞噬指数(P<0.001)。说明二方不...通过对我院抗白血病有效方剂益气养阴方和补气养血方进行免疫功能测定,发现二方既可显著提高T淋巴细胞酸性非特异性酯酶染色(AN A E)阳性率(前者P<0.05,后者P<0.01),又可显著提高粒细胞吞噬率及吞噬指数(P<0.001)。说明二方不但有促进机体细胞免疫的作用,还有增强非特异性免疫的作用。提示二方在白血病治疗中的一个重要作用是可以增强机体的免疫功能。展开更多
I.INTRODUCTION The theory about 3 stages of embryonic hemopoiesis has been accepted by most investigators. Yolk sac is the first hemopoietic organ at the early stage of embryonic.
基金Project supported by the National Basic Research Program (973) of China (No.2009CB119000)the National Natural Science Foundation of China (Nos.20707022,41073090,and 30771255)the Zhejiang Provincial Natural Science Foundation of China (No.Y507220)
文摘The widespread use of organophosphorus pesticides(OPs) poses a great threat to human health and has made the detection of OP residues in food an important task,especially in view of the fact that easy and rapid detection methods are needed.Because OPs have inhibitory effects on the activity of α-naphthyl acetate esterase(ANAE) in plants,in this work we evaluated the possibility of detecting OPs in vegetables with ANAE extracted from commercial flour.The limits of detection(LODs) obtained for methamidophos,dichlorvos,phoxim,dimethoate,and malathion in lettuce samples with crude ANAE were 0.17,0.11,0.11,0.96,and 1.70 mg/kg,respectively.Based on the maximum residue limits(MRLs) for OPs in food stipulated by Chinese laws which are 0.05,0.20,0.05,1.00,and 8.00 mg/kg for methamidophos,dichlorvos,phoxim,dimethoate,and malathion,respectively,the esterase inhibition method with crude ANAE had sufficient sensitivity to detect the residues of dichlorvos,dimethoate,and malathion in lettuce,but it could not be used to guarantee the safety of the same samples if methamidophos or phoxim residue was present.The sensitivity of the method was improved by the use of esterase purified by ammonium sulfate salting-out.The LODs obtained for methamidophos and phoxim with purified esterase were lower than the MRLs for these OPs in food.This is a very promising method for the detection of OP residues in vegetables using crude or purified esterase because of its cheapness,sensitivity,and convenience.
文摘通过对我院抗白血病有效方剂益气养阴方和补气养血方进行免疫功能测定,发现二方既可显著提高T淋巴细胞酸性非特异性酯酶染色(AN A E)阳性率(前者P<0.05,后者P<0.01),又可显著提高粒细胞吞噬率及吞噬指数(P<0.001)。说明二方不但有促进机体细胞免疫的作用,还有增强非特异性免疫的作用。提示二方在白血病治疗中的一个重要作用是可以增强机体的免疫功能。
文摘I.INTRODUCTION The theory about 3 stages of embryonic hemopoiesis has been accepted by most investigators. Yolk sac is the first hemopoietic organ at the early stage of embryonic.
