1. From the Department of Pathology, James H. Quillen College of Medicine, East Tennessee State University (Drs Pang and Ganote), the Department of Ophthalmology, James H. Quillen VAMC and the James H. Quillen College of Medicine (Dr Brown), and the Pathology and Laboratory Medicine Service, James H. Quillen VAMC and the James H. Quillen College of Medicine (Dr Youngberg), Johnson City, Tenn