title: Electron microscopic study of involuting thymus of "lethargic" mutant mice.
mesh_terms: D000367:Age Factors; D000818:Animals; D002462:Cell Membrane; D002467:Cell Nucleus; D003896:Desmosomes; D004847:Epithelial Cells; D008214:Lymphocytes; D008264:Macrophages; D051379:Mice / Q000254:growth & development*; D008854:Microscopy, Electron; D009154:Mutation; D010587:Phagocytosis; D013950:Thymus Gland / Q000166:cytology* / Q000187:drug effects / Q000254:growth & development