Document 0177 DOCN M9440177 TI Trypsin in poliovaccine manufacture [letter] DT 9404 AU Hayflick L SO Lancet. 1994 Mar 5;343(8897):611. Unique Identifier : AIDSLINE MED/94150217 DE Animal *Cells, Cultured Cytological Techniques Haplorhini Human HIV Infections/ETIOLOGY *Poliovirus Vaccine *Trypsin LETTER JOURNAL ARTICLE SOURCE: National Library of Medicine. NOTICE: This material may be protected by Copyright Law (Title 17, U.S.Code).