1. From the Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 601 N Caroline St, JHOC 3245, Baltimore, MD 21287 (S.S., T.G.); Medical Research Institute of New Zealand, Wellington, New Zealand, and Artibiotics, Wellington, New Zealand (C.K.); and Stamford Hospital/Columbia University Vagelos College of Physicians & Surgeons, Stamford, Conn (J.J.).