1. School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, P. R. China
2. Institute for Hepatitis and Virus Research, Hepatitis B Foundation, Doylestown, Pennsylvania 18902, United States
3. Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, Doylestown, Pennsylvania 18902, United States
4. Pharmabridge, Inc., Doylestown, Pennsylvania 18902, United States
5. Institute for Antiviral Research, Utah State University, Logan, Utah 84322, United States