中文摘要：

选取402例服用拉米夫定后出现乙型肝炎病毒（HBV）DNA反弹的慢性乙型肝炎（CHB）患者血清样品，应用荧光PCR法定性检测YMDD变异情况。402例中有309例（76．87％）检测出YMDD变异，其中120例为YVDD变异，74例为YIDD变异，115例为YVDD＋YIDD联合变异；309例YMDD变异患者中同时检测出变异株与野生株占69．26％（214／309），仅检测出变异株占30．74％（95／309）。另外，93例为YMDD野生型阳性。

英文摘要：

402 serum samples were collected from chronic hepatitis B（CHB） patients with HBV DNA rebounding after lamivudine treatment from outpatient clinic and wards of infection department. YMDD variations were detected by using fluorescent PCR. The variants with YMDD mutation were 309 out of the 402 patients（76. 87% ） ,mutation patterns detected in these patients included 120 YVDD ,74 YIDD and 115 mixed type （YIDD ＋ YVDD）. Of all 309 YMDD mutations detected, the YMDD mutant HBV strains coexisting with wild-type virus accounted for 69.26% （214/309） and only YMDD mutant HBV strains 30. 74% （95/309）. Besides, 93 out of the 402 patients were only detected wild-type virus.