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171.
Comparison of high order aberration after conventional and customized ablation in myopic LASIK in different eyes of the same patient 总被引:4,自引:0,他引:4
Purpose: To verify whether there exists any difference in higher order aberrations after undergoing myopic LASIK (laser in situ keratomileusis) with conventional ablation and customized ablation in different eyes of the same patient. Methods: This was a prospective randomized study of 54 myopic eyes (27 patients) that underwent LASIK using the Nidek EC-5000 ex-cimer laser system (Nidek, Gamagori, Japan). Topography-guided customized aspheric treatment zone (CATz) was used in the first eye of the patient (study group) and the other eye of the same patient was operated on with conventional ablation (control group). Higher order aberrations [root-mean-square (RMS) in the 5-mm zone] of both groups were observed with the Nidek OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar between two eyes of the same patient (t=?0.577, P>0.05). Results: Preoperatively, higher order aberrations (RMS in the 5-mm zone) in the CATz ablation and conventional groups were (0.3600±0.0341) μm and (0.2680±0.1421) μm, respectively. This difference was not statistically significant (t=1.292, P>0.05). Three months after LASIK, higher order aberrations (RMS in 5-mm zone) in the CATz ablation and conventional groups were (0.3627±0.1510) μm and (0.3991±0.1582) μm, respectively. No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (t=?0.047, P>0.05). However, a statistically significant increase in higher order aberrations was observed after conventional ablation (t=?5.261, P<0.05). A statistically sig-nificant difference was noted in the increase of higher order aberrations after LASIK between groups (t=?2.050, P=0.045). Con-clusion: LASIK with conventional ablation and topography-guided CATz ablation resulted in the same BSCVA (best specta-cle-corrected visual acuity) 3 month after LASIK. Higher order aberrations were increased, but the increase of higher order ab-errations after customized ablation treatment was less than that after conventional ablation. 相似文献
172.
Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 总被引:5,自引:0,他引:5
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 相似文献
173.
张升 《北京师范大学学报(社会科学版)》2007,(3):87-92
目前通行的浙本职名表与殿本职名表有较大的不同,这是由于两表的编排原则不一造成的。以殿本职名表为主,通过浙本职名表与殿本职名表的比较、参证、互补,更能全面真实地反映四库馆的机构与运作情况。四库馆的机构分为两大系统:其一为翰林院系统,专司《四库全书》的校阅与编修;其二为武英殿系统,专司《四库全书》的缮写、校对与装印。两者互不统属,但又互相配合,统归于总裁官掌控。四库馆中各馆职分工清晰,统属明确,环环相扣,构成一个有机的整体,有利于四库馆的良性运作,保证《四库全书》编修的顺利完成。 相似文献
174.
175.
文科综合实验教学示范中心建设的基本经验——基于协同理论的思考 总被引:1,自引:1,他引:0
文科综合实验教学示范中心的建设,是我国高等学校文科实验教学改革创新的重要成果。基于协同理论,对文科综合实验教学示范中心的孕育过程、决定因素和发展动力3个方面进行了深入思考,并总结了文科综合实验教学示范中心的建设经验。 相似文献
176.
177.
本文在介绍程序流程图及其绘制基本步骤的基础上,结合教学的实例,总结了程序流程图在相关内容教学中的应用。 相似文献
178.
反美主义目前已成为国际关系中的重要现象。韩国的反美主义已经成为影响韩国政治与外交的重要因素。其实质是一种反美情绪而非根深蒂固的意识形态敌对,源自韩国经济发展的促进、民主化的推动、民族主义的膨胀与美韩不平等关系的刺激。通过利益表达机制与媒体报道,韩国反美主义的社会影响与政治效应愈加明显。对美韩同盟、美韩关系、朝鲜半岛问题以及东北亚格局都有所影响。成为研究韩国外交政策不可或缺的元素。 相似文献
179.
肖升 《实验室研究与探索》2011,30(12):78-82
文科[1]综合实验教学中心的出现是典型的“自组织过程”的产物,是高等学校文科实验教学改革创新的重要成果.本文基于协同理论,对文科综合实验教学示范中心的建设工作进行了深入思考,总结了文科综合实验教学示范中心的建设经验及其蕴含的客观规律,阐述了文科实验教学“相变”过程及其“新相”的类型、重点剖析了中心存在的结构不完善的问题及其产生问题的根本原因,提出了破解问题的基本路径:更新高等教育观念;形成发展基本规则;建立相应保障机制和实现扁平化管理. 相似文献
180.
杜春华 《中国教育技术装备》2011,(24):25-26
高校宣传工作人员应该有意识、有目标地培养学生记者,并结合自己的工作进行有效的引导与管理,使学生记者在高校宣传工作中发挥积极的作用,为学校提高影响力、扩大知名度作出应有贡献。在此,笔者结合自己的工作谈一些新的想法和思考,并提出一些建议和意见。 相似文献