Bibliographical noteFunding Information:
From the Departments of Laboratory Medicine and Pathology and Pediatrics. UniversiO' of Minnesota tlealth Sciences Center. Supported by grants from the National Institutes of Health (AM-18883 and AM-13083) and from Burroughs iYellcome. Reprint requests: ltenr), !t. Balfour. Jr.. M.D.. Box 437 Mayo Bldg.. University of Minnesota Health Sciences Center, Minneapolis. AIN 55455. 612-373-8898.