1. Veterans Affairs Medical Center and Department of Medicine, Stanford University (R.M., D.L.), Palo Alto, California 94304
2. Department of Medicine, University of California-San Diego School of Medicine (D.L.S.), La Jolla, California 92093
3. Department of Medicine Columbia University College of Physicians and Surgeons (E.S.), New York, New York 10032
4. Department of Medicine, University of Chicago School of Medicine (M.E.), Chicago, Illinois 60637
5. Indiana University (C.A.Q.), Indianapolis, Indiana 46285