3Felt O, Furrer P, Mayer JM, et al. Topical use of chitosan in ophthalmology: tolerance assessment and evaluation of prccorneal retention [J]. Int J Pharm,1999,180(2) :185-193.
4Shigemasa Y, Minami S. Application of chitin and chitosan for biomaterals[ J]. Biotechnol Genet Eng Rev, 1996,13:383-420.
5Messmer EP, Gottsch JD, Font RL: Blood staining of the cornea: a histopathologic analysis of 16 cases [ J ]. Cornea, 1984-1955,3 ( 3 ) : 205 -212.