方法：将50只兔随机分成实验组及对照组，每组分别25只，建立兔角膜烧伤模型。实验组在角膜烧伤后当天行结膜瓣覆盖术。采用免疫组化法测定两组角膜碱烧伤后不同时间点MMP-9和TIMP-1的表达。

结果：MMP-9在角膜碱烧伤后的3d开始升高，14d达到最高，之后逐渐下降； 而TIMP-1在伤后即有表达，7d有所下降，于14d达到最低，21d达到峰值。实验组MMP-9的表达均明显低于对照组，且角膜碱烧伤后的3，14，21d和28d差异有统计学意义(P<0.05)； 而TIMP-1则明显高于对照组，且角膜碱烧伤后3，14d和21d差异有统计学意义(P<0.05)。

结论：角膜碱烧伤的病理损伤及修复过程中，MMP-9及TIMP-1的表达密切相关。结膜瓣覆盖治疗重度角膜碱烧伤的疗效确切。

METHODS: Rabbit cornea alkali-burns model was made, then 50 rabbits were randomly divided into experimental group(n=25)and control group(n= 25). At the same time the surgery of conjunctival flap covering was given to rabbits of the experimental group. The condition developing of alkali-burned cornea was observed by slit-lamp biomicroscopy, photography in two groups, and the expression of MMP-9 and TIMP-1 was identified by immunohistochemisty in different period.

RESULTS: Expression of MMP-9 increased on the 3^rd day, shown a peak on the 14^th day, and then decreased gradually. TIMP-1 expressed in the early phrase, and later, the level decreased on 7^th day. TIMP-1 level reached the lowest level on 14^th day, then increased and shown a peak on the 21^st day. MMP-9 level of the experimental group was significantly lower than that of the control group(the 3^rd, 14^th, 21^st, and 28^th day), while TIMP-1 level(the 3^rd, 14^th and 21^st day)was higher(P<0.05).

CONCLUSION: During the wound healing process, alkali-burned cornea has close relation with the expression of MMP-9 and TIMP-1. The treatment of conjunctival flap covering for the severe alkali-burned cornea was found to have good effect.