用一种含头尾相连DHBVDNA双体的质粒体内转染2日龄芙蓉鸭，大多数鸭（86％）产生了短暂病毒血症。血清DHBs／preSAg和DHBVDNA于转染后第9天出现，第12～14天达峰值，第28天时多数转阴；少数鸭的病毒血症可持续50天以上。转染鸭肝组织中也检测到复制中间型DHBVDNA的存在。用转染鸭病毒血症期的血清作磷钨酸负染电镜观察，找到了完整的DHBV病毒颗粒，并且用此血清腹腔注射1日龄鸭，60％的鸭被感染成功，证明体内转染后有生物活性的DHBV病毒颗粒的产生。该研究方法的建立．对于研究DHBV变异株．DHBV基因结构与功能的关系等，均有一定理论意义及应用价值。

In vivo transfection with a plasmid-linked tandem DHBV DNA dimer on 2-day old DHBV-free Furong ducklings was carried out. Most of the animals (86%) developed transient viremia. Serum DHBs/pre S Ag and DHBV DNA appeared on 9th day, reached to its peak on12th~14th day and disappeared on 28th after transfection. Whereas, there were a few ducks whose viremia persisted for more than 50 days. DHBV DNA replicative intermediates were alsofound in the liver tissue of transfected ducks. DHBV intact viral panicals were detected in viremic sera under electronic microscope. Intraperitoneal injection of the transfected ducks' viremic sera into 1-day old DHBV-free ducklings resulted in productive DHBV infection on 60% animals,demonstrating the production of biologically active virus after in via transfection. The establishmant of this method is valuable for the research of DHBV variant and the relation between DHBVgene structure and its function.