中文摘要：

提出了一个数学模型，用于研究脉冲投放免疫因子对HBV传染病动力学的影响．通过利用脉冲微分不等式和比较定理，证明了HBV模型的无病周期解的存在性，给出了无病周期解的全局渐近稳定性和系统的持续性的充分条件．研究结果表明：短的投放周期或适当的免疫因子投放量可以导致HBV的清除．

英文摘要：

A mathematical modeL is proposed to study the transmission dynamics of hep atitis B virus （HBV） treated with impulsive releasing immune factor. Using the impulsive differential inequality and comparative theorem, the authors investigate the existence of infection free periodic solution of the impulsive HBV system, the sufficient conditions for the global asymptotic stability of the infection free periodic solution and for the permanence of HBV. Analysis results indicate that a short releasing period of the immune factor or a proper pulse releasing quantity leads to the eradication of the HBV.