[1] Duke Univ, Dept Pediat, Durham, NC 27706 USA
[2] Duke Clin Res Inst, Durham, NC USA
[3] Pfizer Inc, Dept Clin Pharmacol, New London, CT USA
[4] Eshelman Sch Pharm, Chapel Hill, NC USA
[5] Univ Calif San Diego, La Jolla, CA 92093 USA
[6] Cornell Univ, Weill Med Coll, New York, NY 10021 USA
[7] Univ Manchester, Manchester, Lancs, England