Department of Management Information System and Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung City 402, Taiwan, Department of Information Management, National Taichung University of Science and Technology, Taichung City 404, Taiwan, Institute of Nanotechnology, National Chiao Tung University, Hsinchu City 300, Taiwan and Department of Obstetrics and Gynecology, China Medical University and Hospital, Taichung City 404, Taiwan.