The naturally occurring polyamines, eg, putrescine (butane- 1,4-diamine] are important for the regulation of both normal I ,4-diamine), spermidine [N-(3-aminopropyl)-N-(4-amino- and neoplastic cells1 They have high affinities for nucleic butyl)amine], and spermine [N,N'-di-(3-aminopropyl )butane- acids and exhibit a variety of effects on the biosynthesis and ... Published on 01 January 1983. Downloaded by google on 15/02/2016 18:46:44. ... View Article Online / Journal ...