1. Department of Medicine, University of California School of Medicine, Los Angeles, California; the Department of Medicine, University of Washington School of Medicine, Seattle, Washington; and the Department of Medicine, University of New Mexico School of Medicine, Albuquerque, New Mexico.
2. Department of Medicine, University of California School of Medicine, Los Angeles, Calif ornia.
3. Department of Medicine. University of Washington School of Medicine, Seattle, Washington.
4. University of New Mexico School of Medicine, Albuquerque, New Mexico.