1. a Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
2. b Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
3. c Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, 2-3-10, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
4. d Biomaterials Laboratory, Korea Research Institute of Chemical Technology, P.O. Box 107, Yusung, Taejon 305-600, Korea
5. e Biomaterials Laboratory, Korea Research Institute of Chemical Technology, P.O. Box 107, Yusung, Taejon 305-600, Korea
6. f Biomaterials Laboratory, Korea Research Institute of Chemical Technology, P.O. Box 107, Yusung, Taejon 305-600, Korea
7. g Biomaterials Laboratory, Korea Research Institute of Chemical Technology, P.O. Box 107, Yusung, Taejon 305-600, Korea