1. Department of Medicine; University of Arizona Cancer Center; Tucson Arizona 85724-5024
2. Department of Nutritional Sciences; University of Arizona; Tucson Arizona 85721
3. University of Arizona Mel and Enid Zuckerman College of Public Health; Tucson Arizona 85724
4. Division of Research; Kaiser Permanente Northern California; Oakland California 94612
5. Department of Physiology; University of Arizona; Tucson Arizona 85721