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生活方式与儿童干眼相关性的研究进展 被引量:2
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作者 金子群 李从心 温莹 《国际眼科杂志》 CAS 北大核心 2023年第9期1503-1506,共4页
干眼是一种以泪膜稳态失衡为特征的多因素眼表疾病,产生的眼部不适和视力障碍严重影响人们的生活质量和工作质量。近年来随着环境、生活方式的改变,儿童干眼的发病率逐年上升,引发众多关注。干眼的发病受到遗传因素、非遗传因素的影响,... 干眼是一种以泪膜稳态失衡为特征的多因素眼表疾病,产生的眼部不适和视力障碍严重影响人们的生活质量和工作质量。近年来随着环境、生活方式的改变,儿童干眼的发病率逐年上升,引发众多关注。干眼的发病受到遗传因素、非遗传因素的影响,而非遗传因素如生活方式等可以通过人为干预进行改善。生活方式调整具有经济、安全、有效的特点,其对干眼发病风险的保护效力已被大量研究证实,故探明生活方式与儿童干眼的关联性具有十分重要的意义。相关研究分析了视频终端、角膜接触镜、低浓度阿托品滴眼液、睡眠不足、饮食等生活方式与儿童干眼的关系,本文对以上研究结果进行归纳并提出相关预防措施,为预防儿童干眼、延缓疾病发展提供理论依据。 展开更多
关键词 生活方式 儿童 干眼 危险因素 发病机制
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病理性近视并发黄斑裂孔玻璃体切除联合内界膜剥除术后疗效分析 被引量:8
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作者 李姣 张小燕 +3 位作者 原越 李从心 温莹 毕宏生 《国际眼科杂志》 CAS 北大核心 2021年第4期707-710,共4页
目的:探讨玻璃体切除联合内界膜剥除术治疗病理性近视黄斑裂孔的临床效果。方法:回顾性研究。选取2017-01/2019-01于我院确诊的高度近视黄斑裂孔患者18例19眼,将其分为病理性近视组(9例10眼)和非病理性近视组(9例9眼),均接受玻璃体切除... 目的:探讨玻璃体切除联合内界膜剥除术治疗病理性近视黄斑裂孔的临床效果。方法:回顾性研究。选取2017-01/2019-01于我院确诊的高度近视黄斑裂孔患者18例19眼,将其分为病理性近视组(9例10眼)和非病理性近视组(9例9眼),均接受玻璃体切除联合内界膜剥除术。术后随访3~23mo,观察两组患者末次随访时最佳矫正视力(BCVA)、视物变形症状及黄斑裂孔闭合情况。结果:末次随访时,病理性近视组术后BCVA提高6眼,不变2眼,下降2眼,黄斑裂孔完全闭合7眼(70%),裸露型闭合2眼(20%),未闭合1眼(10%);非病理性近视组术后BCVA提高6眼,不变2眼,下降1眼,黄斑裂孔完全闭合8眼(88%),裸露型闭合1眼(11%)。术前两组患者眼轴长度有明显差异,眼轴长度与末次随访时黄斑裂孔闭合率呈负相关(rs=-0.477,P=0.039)。结论:玻璃体切除联合内界膜剥除术治疗高度近视黄斑裂孔可有效改善最佳矫正视力,但病理性近视患者裂孔闭合率低于非病理性近视患者。 展开更多
关键词 病理性近视 黄斑裂孔 玻璃体切除术 内界膜剥除术 黄斑裂孔闭合 眼轴
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Adaptive finite element-element-free Galerkin coupling method for bulk metal forming processes 被引量:5
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作者 Lei-chao liU Xiang-huai DONG cong-xin li 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第3期353-360,共8页
An adaptive finite element-element-free Galerkin (FE-EFG) coupling method is proposed and developed for the numerical simulation of bulk metal forming processes. This approach is able to adaptively convert distorted F... An adaptive finite element-element-free Galerkin (FE-EFG) coupling method is proposed and developed for the numerical simulation of bulk metal forming processes. This approach is able to adaptively convert distorted FE elements to EFG domain in analysis. A new scheme to implement adaptive conversion and coupling is presented. The coupling method takes both advantages of finite element method (FEM) and meshless methods. It is capable of handling large deformations with no need of remeshing procedures, while it is computationally more efficient than those full meshless methods. The effectiveness of the proposed method is demonstrated with the numerical simulations of the bulk metal forming processes including forging and extrusion. 展开更多
关键词 Meshless method Adaptive coupling method Bulk metal forming Numerical simulation
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Automatic recognition of intersecting features of freeform sheet metal parts 被引量:2
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作者 Chun-jie ZHANG Xiong-hui ZHOU cong-xin li 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第10期1439-1449,共11页
This paper presents an approach for recognizing both isolated and intersecting geometric features of freeform surface models of parts,for the purpose of automating the process planning of sheet metal forming.The devel... This paper presents an approach for recognizing both isolated and intersecting geometric features of freeform surface models of parts,for the purpose of automating the process planning of sheet metal forming.The developed methodology has three major steps:subdivision of B-spline surfaces,detection of protrusions and depressions,and recognition of geometric features for sheet metal forming domain.The input geometry data format of the part is based on an IGES CAD surface model represented in the form of trimmed B-spline surfaces.Each surface is classified or subdivided into different curvature regions with the aid of curvature property surfaces obtained by using symbolic computation of B-spline surfaces.Those regions satisfying a particular geometry and topology relation are recognized as protrusion and depression(DP) shapes.The DP shapes are then classified into different geometric features using a rule-based approach.A verified feasibility study of the developed method is also presented. 展开更多
关键词 Feature recognition (FR) Freeform surface Feature intersection Sheet metal forming
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