[1] Univ N Carolina, Chapel Hill, NC 27515 USA
[2] Med Coll Virginia, Richmond, VA USA
[3] Univ Miami, Miami, FL 33152 USA
[4] Minnesota Clin Res Ctr, St Paul, MN USA
[5] Prince Wales Hosp, Randwick, NSW 2031, Australia
[6] Cidade Univ Zeferino Vaz, Campinas, Brazil
[7] Univ Dusseldorf, D-4000 Dusseldorf, Germany
[8] Hosp Gen Valencia, Valencia, Spain
[9] Univ Degli Study, Brescia, Italy
[10] Hosp Tronche, Grenoble, France
[11] Hoffmann La Roche Inc, Nutley, NJ 07110 USA