TY - RPRT TI - Imaging gene expression: principles and assays. AU - S S Gambhir AU - J R Barrio AU - H R Herschman AU - M E Phelps DO - 10.1016/s1071-3581(99)90083-1 UR - https://pubmed.ncbi.nlm.nih.gov/10327107/ ID - 10327107 ER -