RT Journal Article SR Electronic T1 An Amplifier Providing Fixed Background Elimination and Contrast Enhancement in Scanning Systems JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 754 OP 760 VO 7 IS 10 A1 R. E. Clark A1 R. A. Shipley YR 1966 UL http://jnm.snmjournals.org/content/7/10/754.abstract AB