1 Division of Diabetes Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN 37232.
2 Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549; roger.unger@utsouthwestern.edu.
3 Department of Medical Service, Veteran's Administration North Texas Health Care System, Dallas, TX 75216.
4 Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549.