title: Electron microscopic study of the tertiary structure of covalently closed polyoma virus DNA.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004279:DNA, Viral / Q000302:isolation & purification; D005557:Formaldehyde; D008854:Microscopy, Electron; D009691:Nucleic Acid Denaturation; D011120:Polyomavirus; D013696:Temperature
chemical_list: D004279:DNA, Viral; D005557:Formaldehyde