Global asymptotical properties for a diffused HBV infection model with CTL immune response and nonlinear incidence

This article proposes a diffused hepatitis B virus (HBV) model with CTL immune response and nonlinear incidence for the control of viral infections. By means of different Lyapunov functions, the global asymptotical properties of the viral-free equilibrium and immune-free equilibrium of the model are obtained. Global stability of the positive equilibrium of the model is also considered. The results show that the free diffusion of the virus has no effect on the global stability of such HBV infection problem with Neumann homogeneous boundary conditions.     

血清中皮质醇成分分析标准物质的研制

皮质醇是一种重要的肾上腺皮质激素,同时也是一种重要的临床诊断标志物,为保证检测结果具有溯源性、可比性和准确性,研制了血清中皮质醇成分分析标准物质。对血清样品进行分离、过滤、混匀、分装,进行均匀性检验、稳定性考察和定值分析。采用超高效液相色谱–同位素稀释串联质谱(UPLC–ID–MS/MS)法进行定值,混合健康男性血清和健康女性血清中皮质醇的定值结果分别为107.63 ng/g(U=1.44 ng/g,k=2),92.24 ng/g(U=1.68 ng/g,k=2)。采用CCQM–K63a比对样品对定值方法进行验证,测量结果在该比对参考值的不确定度范围内。研制的皮质醇成分分析标准物质符合国家一级标准物质技术要求。