乙酰半胱氨酸治疗丝状角膜炎的机制是（）

A.is a feature of wound healing
B.contains fibroblasts
C.contains thin-walled capillaries
D.often contains granuloma

A.is useful in myopic patients to avoid undercorrection
B.cannot be used in colour blind patients
C.is due to spherical aberration of the eye
D.red light is refracted less than green light
E.at completion of duochrome test，green letters should be clearer than red letters

A.aepitheloid cells
B.round cell infiltrate
C.Langhan’sgiant cells
D.Schauman’s bodies