1. From the Veterans Affairs Medical Center (R.D.F., R.L.A., C.M., R.J., C.F., P.K., S.S., V.P.), Georgetown University School of Medicine (R.D.F., R.L.A., P.K., S.S., V.P.), Department of Health & Human Services (R.K.), and George Washington University (R.L.A., C.F.), Washington, DC.