1. From the Departments of Imaging & Interventional Radiology (J.F.G., D.K.W.Y., F.X., D.W.), Medicine & Therapeutics (M.H., B.T.), and Chemistry (P.G., S.L.L.), Prince of Wales Hospital, The Chinese University of Hong Kong, 30-32 Ngan Shing St, Shatin, NT, Hong Kong.