Antimicrobial activity and biocompatibility of polyurethane and silicone catheters containing low concentrations of silver: a new perspective in prevention of polymer-associated foreign-body-infections. - Boswald,M.; Girisch,M.; Greil,J.; Spies,T.; Stehr,K.; Krall,T.; Guggenbichler,J.P. (Zentralblatt Bakteriologie, 1995)