1. From the Blood Transfusion Service (P.K.B., K.N.R., P.A.R.B., W.H.D., J.A.S., R.S.M.), the Division of Hematology (P.K.B., R.K.L., W.H.D.), the Department of Pathology (B.H.F., J.L., M.Y.C., J.R.S., J.H.), and the Division of Cardiology (E.S.L., R.L.G.), Massachusetts General Hospital, the Division of Hemostasis and Thrombosis (P.K.B., L.M.F., K.E.B., I.T., S.C.W.) and the Division of Hematology and Apheresis Service (B.J.C.), Beth Israel Deaconess Medical Center, and Harvard Medical School (P.K.B.,...