[1] HARVARD UNIV,SCH MED,DEPT MED,BOSTON,MA 02115
[2] JOHNS HOPKINS UNIV,SCH MED,DEPT BIOPHYS,BALTIMORE,MD 21205
[3] JOHNS HOPKINS UNIV,SCH MED,DEPT CELL BIOL & ANAT,BALTIMORE,MD 21205
[4] JOHNS HOPKINS UNIV,SCH MED,DEPT MOLEC BIOL & GENET,BALTIMORE,MD 21205
[5] HARVARD UNIV,SCH MED,DEPT PATHOL,BOSTON,MA 02115