1. Department of Emergency Medicine, School of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea
2. Kohwang Medical Research Institute, School of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea
3. Department of Biomedical Engineering, School of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea
4. Department of Dental Pharmacology, College of Dentistry, Dankook University, Chungnam 330-715, Republic of Korea