哌仑西平抑制近视眼机制的研究

目的 观察哌仑西平对实验性近视的抑制作用,初步探讨其作用机制.方法 将出生后48 h内的纯种M99穗麻雄鸡的右眼缝上眼罩进行遮盖,分别在玻璃体内注入500 μg哌仑西平（MD＋P组）及10 μl生理盐水为阴性对照（SS组）,单纯遮盖作为空白对照（MD组）.同时观察单纯注入500 μg哌仑西平（P组）对正常眼（正常组）的影响.4周后进行验光.运用高效液相色谱（HPLC）联合电化学检测（EC）方法分析实验动物视网膜上多巴胺（DA）及其代谢产物多巴克（DOPAC）水平的变化.结果 MD组和正常组屈光度差异有统计学意义（P＜0.01）.MD组与正常组相比,视网膜DA及其代谢产物DOPAC水平明显降低（P＜0.01）,下降率大于40%.MD＋P组视网膜DA和DOPAC水平与正常组相比差异无统计学意义.结论 500 μg哌仑西平能够抑制实验性近视的产生和发展.哌仑西平可能作用于视网膜上毒覃碱受体（M受体）而引起DA改变,进而抑制近视的产生.     

瞳孔直径和调节刺激对年轻人正视眼单色高阶波阵面像差的影响

目的 探讨不同瞳孔直径下,调节对年轻正视眼单色高阶波阵面像差的影响.方法 干预性试验研究设计.使用光线追踪原理的波阵面像差仪测量12只年轻正视眼自然生理状态,在4.0、3.0、2.0 mm瞳孔直径下,0.00、1.00、2.00、3.00和4.00 D调节刺激下的单色波阵面像差.采用单因素方差分析及最小显著差法多重比较,对获得的数据进行统计学分析.结果 调节松弛下正视眼的总高阶像差、总彗差、总高阶散光、总球差和总三叶草像差的均方根值均随瞳孔直径减小而减小.在4.0、3.0、2.0mm瞳孔直径下,总彗差是调节松弛状态总高阶像差的最主要成分;总高阶像差仅在调节刺激达4.00 D时升高(P<0.05).瞳孔直径4.0 mm时,随调节刺激增加,4阶球差出现从大到小、从正值向负值的变化,但在瞳孔直径为3.0和2.0 mm时,4阶球差始终为正值.3阶水平方向三叶草像差在4.0、3.0、2.0 mm瞳孔直径下均表现出从负值向正值变化的规律.结论 不同瞳孔直径不同调节刺激下,正视眼各项单色高阶波阵面像差发生了不同规律和方向的变化.高阶像差在调节过程变化的意义和对不同注视距离视觉处理过程的作用有待于进一步研究,波阵面像差的研究将从单纯的消除向优化方向发展.     

微爆破模式对前房能量释放的影响

目的探讨超声乳化白内障手术中微爆破模式对前房能量释放与超声时间的影响。设计前瞻性随机对照临床研究。研究对象老年性白内障患者211例(226眼),随机分为微爆破组105例(113眼)与常规连续超声组106例(113眼)。方法两组患者行超声乳化白内障手术,微爆破模式组爆破幅度为30ms,负压为220mmHg,超声能量为60%;连续超声模式组负压为210mmHg,最大超声能量为60%。主要指标术中有效超声能量、超声时间,术后第1天的最佳矫正视力、角膜水肿程度。结果微爆破组和连续超声组,核硬度Ⅰ～Ⅲ级时,术中有效超声能量分别为(3.52±1.58)%,(17.10±7.77)%;超声时间分别为(0.17±0.29)分,(0.99±0.57)分,差异均有统计学意义。术后第1天的最佳矫正视力≥0.5者分别为75眼(79.8%),62眼(65.3%)。核硬度IV～V级时,术中有效超声能量分别为(3.95±1.22)%,(17.33±8.06)%;超声时间分别为(0.25±0.28)分,(1.35±0.79)分,差异均有统计学意义。术后第1天的最佳矫正视力≥0.5者分别为9眼(47.4%),7眼(38.9%)。所有术眼术后第1天角膜水肿程度,微爆破组均较连续超声组轻微。结论在超声乳化白内障手术中,运用微爆破模式,对乳化吸除Ⅰ～Ⅲ级核具有优势;对于IV～V级核,联合拦截劈核技术,也能明显减少前房内能量的释放。     

超声乳化术后急性化脓性眼内炎的2例报告

【目的】探讨2例白内障超声乳化术后急性化脓性眼内炎的临床特点及防治方法。【方法】回顾中山大学中山眼科中心自1999年1月至2003年6月9630例施行白内障超声乳化吸除术的住院患者资料,分析术中去甲万古霉素的使用对急性化脓性眼内炎的预防作用,眼内炎患者的临床表现及治疗经过。【结果】术后发生眼内炎者共2例,发生率为0.021％;该2例患者通过前房冲洗、经睫状体平坦部后段玻璃体切除术及玻璃体腔内注药治疗,眼内炎得到控制,术后均保存了眼球及视力。【结论】超声乳化白内障吸除术后急性化脓性眼内炎的发生率很低;对于发生眼内炎的患者,及时的前房冲洗、后段玻璃体切除术联合玻璃体腔内注药可挽救眼球,并保存一定视力。     

角膜和全眼高阶波前像差的特点及年龄相关性变化的研究

Objective To investigate age-related changes in corneal and ocular monochromatic high-er-order aberrations and elucidate the distribution of corneal primary spherical in Chinese. Methods Using Traeey-iTrace visual function analyzer (EyeSys corneal topography combined with a ray-tracing aberrometer),113 normal eyes of 59 Chinese,mean age of 33.81+20.50 years (range,5-73 years),were evaluated for corneal and ocular monochromatic total higher-order aberrations (HOAs), primary spherical aberration (Z40),total spherical (TS),total coma (TC),and total trefoil aberration (TT) in the central 6mm diameter. Correla-tion analysis was also performed to assess the association between age and both corneal and oeular higher-order aberrations. Results The mean Zemike coefficient of Z40 was (0.27±0.07) ?m (range,0.130～0.451). Al-though corneal Z40 increased slightly with age,the correlation was small and insignificant (r =0.172,p =0.069 ). However, ocular Z40 had a positive correlation with age (r =0.545,p =0.000 ). Analyzer showed positive correlations with age for both corneal (r=0.499,p =0.000) and ocular (r=0.427,p =0.000) HOAs. Positive correlations were also observed between age and both corneal (r=0.149,p =0.021 ) and ocular (r=0.253,p =0.007) TC. Corneal and ocular TT (r =0.344,p =0.000; r=0.185,p =0.050,respectively) were increased with age. No significant correlation was found between corneal TS and age (r =0.180,p =0.057 ), but TS of the whole eye in-creased with age (r =0.560,p =0.000). There was a positive correlation between corneal and ocular HOAs (r =0.327,p=0.000),TC (r=0.233 ,p=0.013),and TT (r=0.481 ,p=0.000) aberration. Conclusions These re-suits also suggest that the ocular HOAs,TC,and TT increase with age,mainly because of the increase in corneal HOAs,TC,and TT; and the ZAO aberration increases with age,mainly because of the increase in Z40 in the internal optics. Individual variability in corneal primary spherical aberration was observed in Chinese.Therefore, preoperative measurement of corneal Z40 is crucial to the selection of aspheric IOL.     

cAMP反应元件结合蛋白(CREB)在正常发育大鼠视皮层的表达研究

正常视觉信息输入对初期视皮层的发育和修饰至关重要。视觉发育的特点是存在一个关键期 ,在此期内控制信息输入将导致皮质联系的显著变化。转录因子 -c AMP反应元件结合蛋白 ( CREB)在多种有机体的信号传导通路中的枢纽作用和其参与长时程突触可塑性的生理活动提示 ,它可能参与了在视皮层发育中发挥重要作用的分子机制。本研究应用免疫组织化学方法和 Western blot技术 ,对 P14、P2 2、P3 0、P45和 P90年龄组 Sprague-Dawley大鼠视皮层内 CREB的免疫反应性进行观察和分析。结果证明 ,CREB在视皮层各层内的蛋白表达时程与视觉发育的关键期一致 ,其免疫反应性在 P2 2至 P45期间达到高水平 ,成年后的蛋白表达出现下调。结论 :视觉可塑性降低的同时存在 CREB表达的显著改变 ,但该蛋白表达改变与突触传递和可塑性的关系尚待阐明     

cAMP反应元件结合蛋白(CREB)在单眼剥夺弱视大鼠视皮层中的表达研究

目前已对突触可塑性的基本特性有了相当程度的认识 ,但对其发育中神经元可塑性的内在分子机制尚待进一步阐明。不少研究提示 ,c AMP反应元件结合蛋白 ( CREB)在学习、记忆和长时程增强 ( LTP)过程中参与长时程突触的可塑性调节 ,推测其在视觉系统可塑性中也发挥着重要作用。本研究通过建立幼年大鼠单眼剥夺弱视模型 ,应用免疫组织化学方法 ,对视觉发育关键期末 ( P45 )大鼠和成年 ( P90 )大鼠视皮层中 CREB和 p CREB的免疫反应性进行观察、比较和分析。结果 :视觉发育关键期内进行单眼视觉剥夺对大鼠视皮层内总 CREB的蛋白表达没有产生显著影响 ,而 p CREB在 P45大鼠的剥夺眼对侧视皮层单眼反应区的 / 、 层中的蛋白表达较剥夺眼同侧视皮层的相应区域弱 ,该差异在该年龄大鼠的双眼反应区及成年后大鼠视皮层内不存在。结论 :CREB可能通过该磷酸化形式在视觉系统可塑性中发挥作用     

角膜和全眼高阶波前像差的特点及年龄相关性变化的研究

Objective To investigate age-related changes in corneal and ocular monochromatic high-er-order aberrations and elucidate the distribution of corneal primary spherical in Chinese. Methods Using Traeey-iTrace visual function analyzer (EyeSys corneal topography combined with a ray-tracing aberrometer),113 normal eyes of 59 Chinese,mean age of 33.81+20.50 years (range,5-73 years),were evaluated for corneal and ocular monochromatic total higher-order aberrations (HOAs), primary spherical aberration (Z40),total spherical (TS),total coma (TC),and total trefoil aberration (TT) in the central 6mm diameter. Correla-tion analysis was also performed to assess the association between age and both corneal and oeular higher-order aberrations. Results The mean Zemike coefficient of Z40 was (0.27±0.07) ?m (range,0.130～0.451). Al-though corneal Z40 increased slightly with age,the correlation was small and insignificant (r =0.172,p =0.069 ). However, ocular Z40 had a positive correlation with age (r =0.545,p =0.000 ). Analyzer showed positive correlations with age for both corneal (r=0.499,p =0.000) and ocular (r=0.427,p =0.000) HOAs. Positive correlations were also observed between age and both corneal (r=0.149,p =0.021 ) and ocular (r=0.253,p =0.007) TC. Corneal and ocular TT (r =0.344,p =0.000; r=0.185,p =0.050,respectively) were increased with age. No significant correlation was found between corneal TS and age (r =0.180,p =0.057 ), but TS of the whole eye in-creased with age (r =0.560,p =0.000). There was a positive correlation between corneal and ocular HOAs (r =0.327,p=0.000),TC (r=0.233 ,p=0.013),and TT (r=0.481 ,p=0.000) aberration. Conclusions These re-suits also suggest that the ocular HOAs,TC,and TT increase with age,mainly because of the increase in corneal HOAs,TC,and TT; and the ZAO aberration increases with age,mainly because of the increase in Z40 in the internal optics. Individual variability in corneal primary spherical aberration was observed in Chinese.Therefore, preoperative measurement of corneal Z40 is crucial to the selection of aspheric IOL.