Objective To develop a method for speciation analysis of selenium in plant samples by H2O2-HNO3 microwave-assisted digestion-HGAFS. Methods Plant samples were prepared using H2O2-HNO3 by microwave-assisted digestion. The contents of soluble inorganic Se(IV)and Se(VI)in the samples were determined by HGAFS after separation most of the soluble organic compounds by XAD-2 resin column in HNO3 medium at pH=3. The contents of soluble Se,insoluble Se,inorganic Se (IV)and Se (VI)and organic Se could be calculated. Results The linear range and detection limit of Se(IV)were 0-80 ?g/L and 0.05 ?g/L respectively. The RSD for the total Se detection was 1.7%(n=5?雪. The total Se content in the reference standard substance obtained by this method agreed well with the reference value. Conclusion The method for preparation of plant samples using microwave-assisted digestion could avoid the loss of Se through volatilization. The pretreatment using XAD-2 resin could remove the interference of organic compounds on detecting results of Se(Ⅳ)in the plant samples,which could widen the application of the method in the speciation analysis. The analytical scheme of the method could determine the contents of total,soluble,insoluble,soluble inorganic Se(IV?雪?Se(VI?雪,and organic Se in plant samples. The method was simple and practical.

Objective To explore the expression of angiopoietin like protein-1(Ang-1)and angiopoietin like protein-2(Ang-2)in type 2 diabetes mellitus(T2DM)and its relationship with angiopathy.Methods Ang-1,Ang-2,FBG,FINS and HbA1c were meas-ured in 120 cases of T2DM,including 32 cases of macroangiopathy,52 cases of microangiopathy and 36 cases without angiopathy, and 50 healthy subjects with physical examination were selected as the control group.The detection results were compared between the two groups.Results Compared with control group,the Ang-1 level in the T2DM group was no statistical difference(P >0.05), but the Ang-2 level was significantly higher than that in the control group(t=2.6,P <0.01).The Ang-2 level in T2DM with com-plicating angiopathy was significantly higher than that in T2DM without angiopathy and closely correlated with the blood vessel number of angiopathy.The Ang-2 level in T2DM was significantly positively correlated with HOMA-IR and HbA1c(r=0.577 and 0.509,P <0.01),and there was no correlation between the Ang-1 level and HOMA-IR(P >0.05).Conclusion The Ang-2 level in the patients with T2DM is significantly increased,which is closely related with HbA1c and insulin resistance,furthermore Ang-2 may participate in the generation and development of pathogenesis in T2DM.