A Phase 1 Study, in Cystic Fibrosis Patients, of the Safety, Toxicity, and Biological Efficacy of a Single Administration of a Replication Deficient, Recombinant Adenovirus Carrying the cDNA of the Normal Cystic Fibrosis Transmembrane Conductance Regulator Gene in the Lung. National Institutes of Health, Bethesda, Maryland