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目的:评价改性壳聚糖滴眼液在白念珠菌性角膜炎动物模型中的治疗作用及安全性。方法:选取10只健康成年雌性新西兰白兔，以右眼为实验眼，采用角膜接触镜法建立浅层白念珠菌性角膜炎模型。经裂隙灯显微镜及角膜刮片显微镜检查结果初步判定造模成功的新西兰白兔，采用随机数字表法分为模型组和改性壳聚糖点眼组，根据真菌培养结果最终判定造模成功的模型兔，另选5只兔为正常对照组，不做处理。正常对照组和改性壳聚糖点眼组局部给予改性壳聚糖滴眼液点眼，每日6次，1周后改为每日4次，继续用药1周后停药；模型组不给予治疗。用药期间每天裂隙灯显微镜下观察各组角膜病灶及眼表变化，于造模后第1、7、14、21、28天行裂隙灯显微镜照相并进行眼部症状评分，并记录角膜愈合时间。停药后继续观察各组实验眼角膜情况2周。结果:8只模型兔实验眼角膜刮片显微镜检查结果为真菌菌丝和孢子阳性，培养分离的菌株与接种菌株一致，造模成功率为80%(8/10)。造模后第7、14、21天，模型组感染程度评分分别为(14.50±0.58)、(6.25±0.50)和(2.50±0.58)分，明显高于相应时间点改性壳聚糖点眼组的(7.25±1.26)、(2.75±0.50)和(1.25±0.50)分，差异均有统计学意义(均P<0.05)。模型组于造模后7 d内，角膜水肿明显加重，中央白色溃疡范围增大，造模后7～28 d角膜溃疡逐渐愈合，平均愈合时间为(24.5±2.6)d，最终遗留角膜瘢痕及新生血管。改性壳聚糖点眼组造模后7 d内角膜浸润明显减轻，造模后14 d角膜刮片镜检及真菌培养结果均为阴性，平均愈合时间为(13.5±1.3)d，明显短于模型组，差异有统计学意义(t＝7.47，P<0.01)。造模后28 d改性壳聚糖点眼组实验眼未见角膜炎复发，治愈率为100%。正常对照组局部用药期间未见眼睑结膜充血水肿及角膜损伤表现。结论:改性壳聚糖滴眼液治疗兔眼浅层白念珠菌性角膜炎模型安全、有效，眼表刺激性小。“,”Objective:To evaluate the clinical efficacy and safety of modified chitosan eye drops on rabbit Candida albicans keratitis model.Methods:Ten healthy female New Zealand rabbits were used to establish the superficial Candida albicans keratitis model by the corneal surface lens method in the right eye.Slit lamp microscopy and corneal scraping and microscopic examination were performed to preliminarily determine whether the keratitis model has been successfully established, the rabbits were then randomly divided into a model group and a modified chitosan group by the random number table method.The successfully established rabbit models which were determined by fungal culture results were retained.Five normal rabbits receiving no intervention served as a normal control group.The experimental eyes in the normal control and modified chitosan groups were treated with modified chitosan eye drops, Six times a day for one week, and subsequently four times a day for one week.No treatment was administered to the model group.The changes of corneal lesions and ocular surfaces were examined by slit lamp microscopy every day.At 1, 7, 14, 21 and 28 days after modeling, the eye condition and corneal clinical scores was assessed by slit lamp microscopy.The corneal conditions in each group was observed for two weeks after drug withdrawal.Results:The corneal scraping and microscopic examination results of eight rabbits models showed that the fungal hyphae and spores were positive.The fungal culture results showed that the separated pathogen was Candida albicans.The success rate of modeling was 80%(8/10). The clinical scores in the model group at 7, 14 and 21 days after modeling were 14.50±0.58, 6.25±0.50 and 2.50±0.58, respectively, and were significantly higher than 7.25±1.26, 2.75±0.50 and 1.25±0.50 in the modified chitosan group (all at P<0.05). In the model group, corneal edema was significantly aggravated, and the central white ulcer area was enlarged within seven days after modeling.Between 7 and 28 days after modeling, the corneal ulcer was gradually healed, while the central corneal scar and neovascularization were remained.The average healing time was (24.5±2.6)days.In the modified chitosan group, the corneal infiltration was significantly alleviated within seven days after modeling, and the fungal hyphae and spores of corneal scraping were negative on the 14th day after modeling.The average healing time in the modified chitosan group was (13.5±1.3)days, which was significantly shorter than that in the the model group (P<0.01). No recurrence of keratitis was observed in the modified chitosan group after two weeks of drug withdrawal.The cure rate was 100%.In the normal control group, the conjunctival hyperemia, corneal edema, and lesions were not observed during topical administration.Conclusion:The treatment with modified chitosan eye drop is effective in a rabbit superficial Candida albicans keratitis model, and have no obvious toxic effects on ocular tissues.