[1] PENN STATE UNIV,MILTON S HERSHEY MED CTR,DEPT PHYSIOL,HERSHEY,PA 17033
[2] MAYO CLIN & MAYO FDN,DEPT LAB MED,ROCHESTER,MN 55901
[3] MAYO CLIN & MAYO FDN,DEPT SURG PATHOL,ROCHESTER,MN 55901
[4] UNIV TEXAS,HLTH SCI CTR,DEPT OPHTHALMOL,SAN ANTONIO,TX 78284
[5] VET ADM HOSP,DIV HEMATOL,LOUISVILLE,KY