title: Observations on a freeze-dried prepration containing the scrapie agent.
mesh_terms: D000818:Animals; D001921:Brain / Q000382:microbiology*; D002725:Chloroform; D005612:Freeze Drying; D000432:Methanol; D051379:Mice; D011328:Prions / Q000302:isolation & purification*; D014020:Tissue Extracts; D014461:Ultracentrifugation
chemical_list: D011328:Prions; D014020:Tissue Extracts; D002725:Chloroform; D000432:Methanol