title: Introduction.
authors.affiliation: a Section of hematology, department of internal medicine , Scott and White Clinic , Temple , Texas.
authors.forename: J B
authors.initials: JB
authors.lastname: Green
authors.affiliation: a Section of hematology, department of internal medicine , Scott and White Clinic , Temple , Texas.
authors.forename: A A
authors.initials: AA
authors.lastname: Trowbridge