Imaging adenoviral-directed reporter gene expression in living animals with positron emission tomography. - Gambhir,S.S.; Barrio,J.R.; Phelps,M.E.; Iyer,M.; Namavari,M.; Satyamurthy,N.; Wu,L.; Green,L.A.; Bauer,E.; MacLaren,D.C.; Nguyen,K.; Berk,A.J.; et al. (Proc Natl Acad Sci USA, 1999)