1. From the Department of Pathology, Rochester General Hospital, University of Rochester School of Medicine, Rochester, New York
2. From the Department of Pathology, University Hospital, Indiana University Medical Center, Indianapolis, Indiana
3. From the Department of Pathology, University Hospital, University of Virginia Medical Center, Charlottesville, Virginia
4. From the Department of Pathology, Barnes Hospital, Washington University School of Medicine, St. Louis, Missouri
5. St. John's Mercy Hospital, Washington University School of Medicine, St. Louis, Missouri
6. Department of Pathology, Cleveland Clinic, Case Western Reserve University School of Medicine, Cleveland, Ohio.