K Tan1, C L Cheung2, C Y Yeung3, D Siu1, J Leung4, H K Pang5. 1. Department of Medicine, The University of Hong Kong. 2. Department of Pharmacology and Pharmacy, The University of Hong Kong. 3. Endocrine and Diabetes Centre, Hong Kong Sanatorium and Hospital. 4. Department of Medicine, Ruttonjee Hospital. 5. Department of Medicine, Pamela Youde Nethersole Eastern Hospital.