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Changes of matrix metalloproteinases in the stroma after corneal cross-linking in rabbits

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 26-31页

作者： hong-zhen jia Xu Pang Xiu-Jun Peng Department of Ophthalmology the Sixth Medical Center of Chinese PLA General HospitalBeijing 100048China

AIM:To observe changes in the content of matrix metalloproteinases(MMPs)in the corneal stroma after corneal cross-linking(CXL)in rabbits,and further explore the corneal pathophysiological process after ***:Forty-two rabbits(42 eyes)were randomly divided into seven *** group served as the control group,while the other six groups were treated with *** concentrations of MMPs in corneal stroma were evaluated through parallel reaction monitoring at baseline and 3,7,15,30,90,and 180 d after ***:The levels of MMP-2 in the corneal stroma of rabbits were 0.76±0.07,2.78±1.39,4.12±0.69,2.00±0.29,2.00±0.30,1.22±0.18,and 1.35±0.18(10^(-9)mol/g)at baseline and 3,7,15,30,90,and 180 d after treatment,*** contents of tissue inhibitor of metalloproteinase-1(TIMP-1)were 1.83±0.26,7.94±0.58,6.95±2.64,3.81±0.48,3.07±0.92,1.72±0.19,and 1.69±0.74(10^(-9)mol/g),*** ratios of MMP-2/TIMP-1 were 0.42±0.33,0.36±0.20,0.62±0.10,0.54±0.15,0.68±0.13,0.71±0.10,and 0.68±0.09,*** CXL,the expression of MMP-2 and TIMP-1 in the rabbit corneal stroma was initially increased and subsequently *** levels of MMP-2 remained higher than those recorded at baseline 180 d after treatment,but it was not statistically *** levels of TIMP-1 returned to baseline levels at 90 d after *** ratio of MMP-2/TIMP-1 started to rise from 7 d after *** was significantly higher than that calculated at baseline 30-180 d after *** results for MMP-1,-3,-7,-9,-13,and TIMP-2 were ***:CXL can lead to changes in the content of MMP-2 and TIMP-1 in the rabbit corneal *** ratio of MMP-2/TIMP-1 remains higher versus baseline,indicating that MMP-2 is involved in the corneal pathophysiological process after CXL.

关键词： corneal cross-linking keratoconus rabbit riboflavin matrix metalloproteinase

Risk of anxiety and depression in patients with uveitis:a Meta-analysis

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International Journal of Ophthalmology(English edition) 2022年第8期15卷 1381-1390页

作者： Bei Cui hong-zhen jia Li-Xiong Gao Xiao-Fei Dong Senior Department of Ophthalmology the Third Medical Centre of Chinese People’s Liberation Army General HospitalBeijing 100039China Department of Ophthalmology No.967 Hospital of the Joint Logistics Support Force of the Chinese PLADalian 116000Liaoning ProvinceChina

AIM:To quantitatively evaluate the risk of anxiety and depression in patients with uveitis via performing a ***:Three electronic database(Pub Med,Embase,and Cochrane Library databases)were searched for studies recording data about uveitis and anxiety as well as depression simultaneously up to January *** incidence rate and standard mean difference(SMD)with a 95%confidence interval(95%CI)were calculated to analyse the association using random-effects models based on heterogeneity ***:In total,12 observational studies containing 874 patients with uveitis were *** results showed that there was a significant association between uveitis and anxiety(SMD=0.97,95%CI:0.39 to 1.54,P=0.0009)and depression(SMD=0.79,95%CI:0.51 to 1.07,P<0.00001).The overall morbidities of anxiety and depression in patients with uveitis were 39%and 17%,*** subgroup analysis,the heterogeneity actually came from different kinds of ***,the incidence rates of both anxiety and depression were relatively low in patients with anterior uveitis(33%and 15%),moderate in patients with infectious uveitis(46%and 22%),and high in patients with unspecified uveitis(59%and 35%).CONCLUSION:It is preliminarily indicated that patients with uveitis may have a high risk of anxiety and *** and psychologists should pay more attention to the psychological state when dealing with patients with *** high-quality studies with detailed direct data are needed to draw more precise conclusions.

关键词： anxiety depression uveitis Meta-analysis

Iontophoresis-assisted corneal crosslinking using 0.1% riboflavin for progressive keratoconus

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 717-722页

作者： hong-zhen jia Xu Pang zheng-Jun Fan Na Li Gang Li Xiu-Jun Peng Chinese PLA Medical School Beijing 100853 China Department of Ophthalmology Chinese PLA Navy General Hospital Beijing 100048 China

AIM：To report the clinical results of iontophoresis-assisted epithelium-on corneal crosslinking（I-CXL） using 0.1% riboflavin in distilled water for progressive keratoconus. METHODS：In this prospective clinical study, we examined 94 eyes of 75 patients with progressive keratoconus who were treated with I-CXL using 0.1% riboflavin in distilled water. Best correct visual acuity（BCVA）, Scheimpflug tomography, corneal topography, anterior segment optical coherence tomography, intraocular pressure, and endothelial cell density were evaluated at baseline and 1, 3, 6, 12, and 24 mo after ***：After 24 mo I-CXL, compared to the level at baseline, BCVA significantly improved 0.14±0.07（P=0.010）; mean keratometry signifi cantly decreased 0.72±1.97（P=0.021）; maximum keratometry significantly reduced 2.30±5.01（P=0.014）; central keratoconus index significantly reduced 0.04±0.08（P=0.007）. The demarcation line was visible in 83.1% of eyes at 1mo after treatment, with a depth of 298.95±51.97 μm, and gradually indistinguishable. One eye had repeat treatment. Intraocular pressure and endothelial cell density did not change ***：I-CXL using 0.1% riboflavin halts keratoconus progression within 24 mo, resulting in a significant improvement in visual and topographic parameters. Moreover, the depth of the demarcation line is similar to that previously reported in standard epithelium-off CXL procedures.

关键词： corneal cross-linking iontophoresis keratoconus distilled water riboflavin

Iontophoresis-assisted versus standard corneal crosslinking for progressive keratoconus

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Annals of Eye Science 2017年第1期2卷 28-34页

作者： hong-zhen jia Xu Pang zheng-Jun Fan Xiu-Jun Peng Department of Ophthalmology Chinese PLA Navy General HospitalBeijing 100048China

Background:To compare the safety and efficacy of iontophoresis-assisted epithelial-on corneal crosslinking(I-CXL)using 0.1%riboflavin-distilled water solution with standard epithelium-off corneal crosslinking(S-CXL)for progressive ***:In a retrospective analysis,progressive keratoconus patients treated with I-CXL(17 eyes of 17 patients)or S-CXL(13 eyes of 13 patients)were *** patients were followed up at least 12 *** patients underwent detailed ophthalmologic examinations involving pre-and postoperative visual acuity,topographic parameters and ***-and postoperative complications were ***:No statistically significant differences were observed between the two groups at baseline with respect to visual acuity,age and thinnest corneal thickness(TCT).The postoperative decreases of K1 and Kmean in the S-CXL group represented statistically significantly better results than in the I-CXL group(t=2.093 and 2.123,P=0.046 and 0.043,respectively).Alterations of other parameters showed no significant differences between the two *** were no failure cases in the two ***:I-CXL using 0.1%riboflavin-distilled water solution provided effective treatment for progressive keratoconus at 12-month ***,the decreases of K1 and Kmean caused by I-CXL were less than those by *** treatment time,postoperative patient pain and risk of infection in I-CXL are all less than those in S-CXL,I-CXL is unable to completely replace S-CXL for progressive keratoconus temporarily.

关键词： Keratoconus corneal crosslinking iontophoresis riboflavin

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平面柔性多体系统正碰撞动力学建模理论研究

计算力学学报 2010年第6期27卷 1042-1048页

作者：董富祥洪嘉振上海交通大学工程力学系上海200240

针对目前柔性多体系统碰撞动力学建模方法存在的不足,对影响碰撞动力学仿真的主要因素如柔性体建模和碰撞初始条件进行分析,建立起基于变约束的柔性体碰撞动力学方程。首先,为了解决子结构法在处理碰撞界面搜索时面临的难题,引入多体系... 详细信息

针对目前柔性多体系统碰撞动力学建模方法存在的不足,对影响碰撞动力学仿真的主要因素如柔性体建模和碰撞初始条件进行分析,建立起基于变约束的柔性体碰撞动力学方程。首先,为了解决子结构法在处理碰撞界面搜索时面临的难题,引入多体系统柔性体有限元描述方法,推导出凸形柔性体接触点间法向位移约束的二阶导数形式。其次,从碰撞引起的接触界面速度不连续机理出发,结合连续介质力学间断面理论,给出碰撞瞬时由物体本身物理性质决定的接触位置处速度跳跃公式。最后对两弹性圆盘低速碰撞问题进行数值仿真。结果表明本文提出的改进方法符合力学基本原理,仿真结果满足收敛性要求。

关键词：平面柔性多体系统碰撞建模方法速度跳跃条件间断面

A recursive formulation based on corotational frame for flexible planar beams with large displacement

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Journal of Central South University 2018年第1期25卷 208-217页

作者： WU Tan-hui LIU Zhu-yong hong jia-zhen School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

A forward recursive formulation based on corotational frame is proposed for flexible planar beams with large *** traditional recursive formulation has been successfully used for flexible mutibody dynamics to improve the computational efficiency based on floating frame,in which the assumption of small strain and deflection is *** proposed recursive formulation could be used for large displacement problems based on the corotational *** means that the recursive scheme is used not only for adjacent bodies but also for adjacent beam *** nodal relative rotation coordinates of the planar beam are used to obtain equations with minimal generalized coordinates in present *** proposed formulation is different from absolute nodal coordinate formulation and the geometrically exact beam formulation in which the absolute coordinates are *** recursive scheme and minimal set of dynamic equations lead to a high computational efficiency in numerical *** examples are carried out to demonstrate the accuracy and validity of this *** all of the examples,the results of the present formulation are in good agreement with results obtained using commercial software and the published ***,it is shown that the present formulation is more efficient than the formulation in ANSYS based on GEBF.

关键词： recursive formulation multibody dynamics large displacement beam corotational frame

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中心刚体-柔性梁耦合系统离散模型的研究

计算力学学报 2009年第3期26卷 420-423页

作者：覃晓英洪嘉振上海交通大学工程力学系上海200240

采用数值仿真对由中心刚体、柔性梁组成的刚-柔耦合系统的动力学离散模型进行了研究。考虑到刚柔-耦合系统的控制方程没有精确解析解,只能寻求数值解,最广泛使用的离散方法是有限元,但其广义坐标数目过于庞大,因此本文探讨了采用经典结... 详细信息

采用数值仿真对由中心刚体、柔性梁组成的刚-柔耦合系统的动力学离散模型进行了研究。考虑到刚柔-耦合系统的控制方程没有精确解析解,只能寻求数值解,最广泛使用的离散方法是有限元,但其广义坐标数目过于庞大,因此本文探讨了采用经典结构动力学中不同边界的模态函数离散动边界下刚柔耦合动力学方程的可行性及各自的优劣,得到刚柔耦合系统的模态缩减规律。

关键词：刚-柔耦合系统离散有限元模态缩减

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柔性多体系统动力学研究现状与展望

计算力学学报 2008年第4期25卷 411-416页

作者：刘铸永洪嘉振上海交通大学工程力学系上海200240

对柔性多体系统动力学的研究现状进行了概括和总结,主要从柔性体建模方法、刚柔耦合动力学、接触碰撞问题、多物理场耦合、微分代数方程求解技术、控制方法、设计优化及软件开发和实验研究等几个研究方向进行总结,并对未来的研究方向做... 详细信息

对柔性多体系统动力学的研究现状进行了概括和总结,主要从柔性体建模方法、刚柔耦合动力学、接触碰撞问题、多物理场耦合、微分代数方程求解技术、控制方法、设计优化及软件开发和实验研究等几个研究方向进行总结,并对未来的研究方向做了展望。

关键词：柔性多体系统动力学建模理论计算方法试验研究

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温度场中的柔性梁系统动力学建模

振动工程学报 2006年第4期19卷 469-474页

作者：刘锦阳洪嘉振上海交通大学工程力学系上海200030

研究温度场下带集中质量的柔性梁系统的动力学问题。考虑几何非线性,在纵向变形与轴向伸长的关系式中计及了与横向变形有关的二次耦合项。考虑温度变化对系统动力学性态的影响,在本构关系式中计及了热应变。用假设模态法对各柔性梁进行... 详细信息

研究温度场下带集中质量的柔性梁系统的动力学问题。考虑几何非线性,在纵向变形与轴向伸长的关系式中计及了与横向变形有关的二次耦合项。考虑温度变化对系统动力学性态的影响,在本构关系式中计及了热应变。用假设模态法对各柔性梁进行离散,从虚功原理出发,根据各柔性梁之间的运动学约束关系,建立了带集中质量的柔性梁系统的动力学方程。仿真结果表明,即使在转速较低的情况下,随着集中质量的增大和温度的急剧变化,纵向变形的二次耦合项的影响不容忽视,此外,温度的变化还引起轴向变形和轴向约束力高频振荡。

关键词：温度场集中质量柔性梁系统几何非线性动力学