Jin Seok Kim, Ju In Eom, June-Won Cheong, Ae Jin Choi, Jin Koo Lee, Woo Ick Yang, and Yoo Hong Min*
Department of Internal Medicine, Brain Korea 21 Research Team of Nanobiomaterials for the Cell-Based Implants, Medical Research Center, Department of Pathology,Yonsei University College of Medicine, Seoul, Korea
*Requests for reprints: Yoo Hong Min, Department of Internal Medicine, Yonsei University College of Medicine, Seodaemun-ku, Shinchon-dong 134, Seoul 120-752, Korea.