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101.
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
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刘文典《庄子补正》一书,对《庄子》书中的衍、脱、讹、倒等疑误都给予了详尽的校勘和补充。有些意见中肯,可以据以订正原文;有些可备一说.极有参考价值。今就有关条目作一辨析整理,以益来者。 相似文献
109.
Yongqiang Sun Linghong Ni Yiming Zhao Xiao-Liang Shen Nan Wang 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(6):3156-3174
Although Massive Open Online Courses (MOOCs) attract millions of people to enroll in their courses, the completion rate for most courses is very low. A majority of MOOCs students are not fully engaged in MOOCs, thus leading them to quit in the early stage of the courses. Therefore, it is important to investigate students’ engagement in MOOCs. Drawing on self-determination theory and the theory of relationship quality, this study proposes a model that conceptualizes the MOOCs engagement as consisting of psychological engagement and behavioral engagement and explores the antecedents of students’ engagement in MOOCs. The research model is tested using data collected from 374 students of Chinese University MOOC. The results show that fulfillment of three basic psychological needs for autonomy, competence and relatedness have significant positive effects on intrinsic motivation, increasing students’ psychological engagement in MOOCs. Relationship quality significantly predicts students’ psychological engagement, and psychological engagement promotes behavioral engagement in MOOCs. Implications for research and practice as well as limitations of this study are discussed finally. 相似文献
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从实验队伍结构谈对实验人员的考评和激励机制的思考 总被引:1,自引:0,他引:1
从对实验队伍的年龄结构,职称结构、学历结构和职务结构的分析,提出了对实验人员的考核评估和激励机制的思考。 相似文献