1. Departments of Pediatrics and Physiology, University of Tennessee Health Science Center/LeBonheur Children's Medical Center, Memphis, Tennessee and Division of Pediatric Emergency Medicine, Children's Hospital Medical Center, Cincinnati, Ohio.
2. Department of Physiology, University of Tennessee Health Science Center, and LeBonheur Children's Medical Center, Memphis, Tennessee.
3. Departments of Pathology and Anatomy and Neurobiology, University of Tennessee Health Science Center, and LeBonheur Children's Medical Center, Memphis, Tennessee.
4. Department of Pediatrics, University of Tennessee Health Science Center, and LeBonheur Children's Medical Center, Memphis, Tennessee.