title: Class II defective avian sarcoma viruses: comparative analysis of genome structure.
mesh_terms: D001355:Alpharetrovirus / Q000235:genetics*; D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D002478:Cells, Cultured; D002642:Chick Embryo; D004247:DNA / Q000235:genetics; D003673:Defective Viruses / Q000235:genetics*; D005347:Fibroblasts; D005814:Genes, Viral; D006378:Helper Viruses / Q000235:genetics; D009154:Mutation; D009693:Nucleic Acid Hybridization; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic
chemical_list: D012367:RNA, Viral; D004247:DNA