1. Department of Chemistry, National Chung Hsing University, Taichung 403, Taiwan
2. Department of Medical Applied Chemistry, Chung Shan Medical University, Taichung 402, Taiwan
3. Department of Electrophysics, National Chiao Tung University, Hsinchu 300, Taiwan
4. Department of Applied Chemistry, National Chi Nan University, Puli 545, Taiwan
5. Department of Medical Education, Chung Shan Medical University Hospital, Taichung 402, Taiwan