1. Oral Cancer Research Center, Changhua Christian Hospital, Changhua 500, Taiwan, R.O.C.
2. School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung 40201, Taiwan, R.O.C.
3. Post Baccalaureate Medicine, National Chung Hsing University, Taichung 40201, Taiwan, R.O.C.