板层角膜移植联合自体角膜瓣填垫治疗边缘性角膜穿孔

目的:探讨用自体角膜瓣封闭角膜穿孔,联合板层角膜移植治疗边缘性角膜溃疡穿孔的临床疗效。方法:对17例(17眼)不同病因引起的边缘性角膜溃疡穿孔患者行自体角膜瓣填垫及板层角膜移植,术后对植片愈合、虹膜前粘连、继发青光眼、视力、免疫排斥反应进行观察。结果:随访3～12(平均6)mo,所有患者植片透明,未见排斥反应,层间积液2例至术后1mo吸收,前房轴深正常,虹膜粘连于角膜穿孔处3例,无继发青光眼。随访>3mo,视力较术前提高12眼,无进步5眼。结论:板层角膜移植联合自体角膜瓣填垫是治疗边缘性角膜穿孔的有效方法。     

Femtosecond laser deep lamellar keratoplasty

We aimed to develop a novel and effective technique for creating a smooth deep lamellar dissection of the cornea using a femtosecond (FS) laser for deep anterior lamellar keratoplasty (DALK), we conducted a retrospective eye bank study. Thirteen fresh human corneas were mounted on an artificial anterior chamber, and deep lamellar cuts were made with a 500-kHz VisuMax FS laser at a level of 50–80 mm anterior to the Descemet’s membrane (DM). A posterior diameter of 8 mm with a side cut angle of 110° was used for the anterior penetrating side cut. The anterior lamellar tissue was bluntly dissected. The residual posterior stromal beds and side cuts were examined with microscopy and intraoperative optical coherence tomography (OCT) and post-cut endothelial cell evaluations. All corneas revealed a smooth residual posterior stromal bed without any visible irregularities or ridges by microscopy and OCT imaging. Six corneas were suitable for post-cut endothelial cell evaluation 2 days after laser cut, with no significant endothelial cell loss post-laser and blunt dissection of the posterior stroma. FS laser deep lamellar keratoplasty utilizing an ultrafast laser to produce a smooth deep stromal dissection followed by blunt dissection and removal of the anterior stromal tissue yields a consistent and smooth residual stromal bed. The creation of a smooth lamellar dissection in the deep posterior cornea may result in more consistent DALK without the need for air bubble or manual baring of DM that has the risk for DM perforation.     

A prospective study investigating the long-term stability of changes in astigmatism following arcuate lamellar keratotomy (ALK): 3-year results

Introduction: The correction of low to moderate astigmatism is possible today by means of photoablation (PRK), while the treatment of moderate and higher astigmatism still involves refractive keratotomy. Experience has shown that cataract surgery, using modern tunnel techniques with self-healing incisions, results in earlier stability in both the refractive outcome and wound healing. In this study, we attempted to combine the advantages of lamellar keratotomy with those of a pair-wise T-incision as arcuate lamellar keratotomy (ALK). Patients and methods: The clinical outcome of 41 patients who underwent ALK was investigate in a prospective study over a period of 3 years. The pre- and postoperative investigations undertaken included the measurement of astigmatism using a Zeiss keratometer, uncorrected visual acuity, and corrected glare vision using a Humphrey autorefractor. All patients had astigmatism between 2.0 and 7.0 D. Together with a uniform arcuate incision, we used 7 mm (n = 26) and 8 mm (n = 15) mm zones for correction. Results: The average preoperative astigmatism was 4.01 ± 1.90 (median, 3.50) D. After a 3-year follow-up the average postoperative astigmatism was 1.59 ± 1.29 (median, 1.38) D. The astigmatic change induced (Jaffé) after 3 years was about 3.23 ± 2.23 (median, 3.16) D. The average uncorrected visual acuity (log MAR) before ALK was 0.20 ± 0.12 (median, 0.22) and after follow-up, 0.41 ± 0.14 (median, 0.39). Corrected glare vision before surgery was 0.23 ± 0.19 (median, 0.10) and afterwards, 0.25 ± 0.22 (median, 0.14). Conclusions: Arcuate lamellar keratomy (ALK) stood the test as a routine clinical procedure for correction of moderate astigmatism with stable postoperative functional outcomes. We did not find impairment of glare vision following this procedure.      

全眼球冷冻保存角膜的板层角膜移植

全眼球液氮冷冻保存法是一种长期保存角膜材料的方法,在板层角膜移植中可收到与新鲜角膜相仿的临床效果。取全眼球液氮冷冻保存的角膜为３５例角膜病变患者实施了板层角膜移植术,术后随访１～３年,角膜透明率（包括半透明率）９７％,３４眼术后视力均有不同程度提高。同时介绍了全眼球液氮冷冻保存方法的操作技术     

飞秒激光辅助的大气泡法深板层角膜移植术治疗圆锥角膜后视觉质量

目的 观察飞秒激光辅助的大气泡法深板层角膜移植术(deep anterior lamellar keratoplasty,DALK)治疗圆锥角膜的视觉质量.方法 使用自身对照观察法,纳入30例(50眼)圆锥角膜患者,均行飞秒激光下大气泡法DALK治疗,随访1 a观察疗效.结果 30例(50眼)患者均顺利完成手术,术后早期术眼角膜植片均透明,角膜生理厚度恢复,植片与植床后弹力层贴合较好;术后7d、1个月、6个月、1 a患眼裸眼视力、最佳矫正视力均高于术前(均为P＜0.05),术后不同时间点间差异均无统计学意义(均为P＞0.05).术后不同时间点角膜曲率、角膜散光均较术前显著降低,角膜最薄点厚度较术前显著增加(均为P＜0.05),术后7d、1个月、6个月、1 a间各指标差异均无统计学意义(均为P＞0.05).术前内皮细胞密度为(2989.34±294.52)个·mm.,术后1 a为(2821.19±325.51)个·mm-2,角膜内皮细胞丢失率为(5.62±0.56)％,术后7d、1个月、6个月、1 a间差异不显著(均为P＞0.05).术中未见并发症发生;术后1眼伤口哆开,1眼缝线松弛,1眼发生基质层免疫排斥反应,未见其他并发症发生.结论 圆锥角膜行飞秒激光辅助的大气泡法DALK治疗,疗效确切,安全性高,是中晚期患者较佳的术式选择.     

微波提取法对槟榔中槟榔碱的提取率的影响

目的探讨提高槟榔中槟榔碱提取率的方法。方法用微波提取法提取槟榔碱,用薄层扫描仪检测以考察方法的可行性。结果槟榔碱的提取率明显提高。结论本方法具有快速、省时、节能等诸多优点,可适用于槟榔碱的工业化大生产。     

Pulmonary surfactant: No mere paint on the alveolar wall

Abstract The gas-liquid interface within the alveolus is completely lined with a complex mixture of lipids and unique proteins termed pulmonary surfactant, which both reduces surface tension and permits it to vary directly with the radius of curvature. In this way it minimizes the work of breathing and permits alveoli of different sizes to exist in equilibrium. However, surfactant does far more in that it also controls fluid balance in the lung and appears to play a key role in host defence. Either a deficiency in surfactant or an aberrant surfactant results in atelectasis and oedema. The surfactant system is very dynamic: alveolar surfactant phosphatidylcholine, the principal component, having a half life of only a few hours, with as much as 85% being recycled. Although distortion of the alveolar type II cell is now accepted as the principal stimulus for release, much remains to be discovered of modulating factors and intracellular signalling in the control of surfactant homeostasis. Likewise, many questions remain concerning the control of synthesis of the surfactant phospholipids, neutral lipids and proteins and their assembly into the tubular myelin form of alveolar surfactant, the refining of the monolayer with breathing, the control of re-uptake of different components into the type II cells and the roles of the proteins.     

薄层扫描法测定玉台净注洗液中苦参碱的含量

目的:建立玉台净注洗液中苦参碱含量测定方法.方法:用薄层扫描法测定苦参碱的含量.结果:苦参碱在0.5～2.5 μg间线性关系良好,r=0.9996,平均回收率为98.3%.结论:所建方法简便、准确、重现性好,适用于该制剂的质量控制.     

Full-thickness lamellar keratoplasty. A histologic study in human eyes

Four human eyes, obtained 38 days to 5 years after full-thickness lamellar keratoplasty, were studied by light microscopy for evidence of fibroblast proliferation and collagen formation between the donor Descemet's membrane and the recipient stromal bed. There was delayed healing in the membrane to stroma interface, but at the graft margins a relatively normal stroma-to-stroma healing response was evident. Even in the five-year specimen, bridging of recipient collagen to donor Descemet's membrane was noted only where it was associated with subgraft vascularization. All donor endothelium had disappeared. These studies indicate that in human eyes, retention of Descemet's membrane results in a weaker total graft-host bond than provided by conventional lamellar keratoplasty. In addition, this altered healing may predispose to pseudoanterior chambers that may decrease visual acuity and diminish the theoretical optical advantages of a smooth Descemet's membrane in the graft host interface.