title: [Changes of toxicity assessment using LD50 values].
authors.forename: Takeshi
authors.initials: T
authors.lastname: Morita
mesh_terms: D000818:Animals; D005260:Female; D017408:Guidelines as Topic; D007928:Lethal Dose 50; D008297:Male; D051381:Rats; D018675:Toxicity Tests / Q000379:methods* / Q000592:standards