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Multifractal estimation of NMR T_(2) cut-off value in low-permeability rocks considering spectrum kurtosis: SMOTE-based oversampling integrated with machine learning

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Petroleum Science 2023年第6期20卷 3411-3427页

作者： Xiao-Jun Chen rui-xue zhang Xiao-Bo Zhao Jun-Wei Yang zhang-Jian Lan Cheng-Fei Luo Jian-Chao Cai MOE Key Laboratory of Tectonics and Petroleum Resources Wuhan430074HubeiChina Department of Chemical Engineering and Analytical Science The University of ManchesterManchesterM139PLUK Jianghan Oilfied SINOPECQianjiang430063HubeiChina Hainan Branch of CNOOC Ltd Haikou570311HainanChina CNOOC EnerTech-Drilling&Production Co.CNOOC Central Laboratory(Zhanjiang) Zhanjiang524057GuangdongChina National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China

The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in petrophysical characterization of petroleum reservoirs. This study focuses on the systematic analysis of T_(2) spectra and T_(2) cut-off values in low-permeability reservoir rocks. Analysis of 36 low-permeability cores revealed a wide distribution of T_(2) cut-off values, ranging from 7 to 50 ms. Additionally, the T_(2) spectra exhibited multimodal characteristics, predominantly displaying unimodal and bimodal morphologies, with a few trimodal morphologies, which are inherently influenced by different pore types. Fractal characteristics of pore structure in fully water-saturated cores were captured through the T_(2) spectra, which were calculated using generalized fractal and multifractal theories. To augment the limited dataset of 36 cores, the synthetic minority oversampling technique was employed. Models for evaluating the T_(2) cut-off value were separately developed based on the classified T_(2) spectra, considering the number of peaks, and utilizing generalized fractal dimensions at the weight 0. The primary objective of this work is to gain insights into the relationship between the kurtosis of the T_(2) spectrum and pore types, as well as to predict the T_(2) cut-off value of low-permeability rocks using machine learning and data augmentation techniques.

关键词： Nuclear magnetic resonance Low-permeability porous media T_(2)cut-off value Fractal and multifractal Data augmentation Machine learning

Oxidative stress,epigenetic regulation and pathological processes of lens epithelial cells underlying diabetic cataract

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Advances in Ophthalmology Practice and Research 2023年第4期3卷 180-186页

作者： Zaoxia Guo Xiaopan Ma rui xue zhang Hong Yan Shaanxi Eye Hospital Xi'an People's Hospital(Xi'an Fourth Hospital)Affiliated People's Hospital of Northwest UniversityXi'anShaanxiChina Xi'an Key Laboratory of Stem Cell and Regenerative Medicine Institute of Medical ResearchNorthwestern Polytechnical UniversityXi'anShaanxiChina

Background:Cataract is a blinding disease *** is an age-related disease that mainly occurs in people over 65 years *** is also prevalent in patients with diabetes mellites(DM).The pathological mechanisms underlying diabetic cataract(DC)are more complex than that of age-related *** have identified that polyol pathway,advanced glycation end products(AGEs)and oxidative stress are the primary pathogenesis of *** recent years,molecular-level regulations and pathological processes of lens epithelial cells(LECs)have been confirmed to play roles in the initiation and progression of DC.A comprehensive understanding and elucidation of how chronic hyperglycemia drives molecular-level regulations and cytopathological processes in the lens will shed lights on the prevention,delay and treatment of *** text:Excessive glucose in the lens enhances polyol pathway and AGEs *** pathway causes imbalance in the ratio of NADPH/NADPt and NADH/*** in NADPH/NADPt ratio compromises antioxidant enzymes,while increase in NADH/NADt ratio promotes reactive oxygen species(ROS)overproduction in mitochondria,resulting in oxidative *** stress in the lens causes oxidation of DNA,proteins and lipids,leading to abnormalities in their structure and *** of proteins by AGEs decreases solubility of *** glucose triggered epigenetic regulations directly or indirectly affect expressions of genes and proteins in *** in autophagic activity,increases in fibrosis and apoptosis of LECs destroy the morphological structure and physiological functions of the lens epithelium,disrupting lens ***:In both diabetic animal models and diabetics,oxidative stress plays crucial roles in the formation of *** regulations,include lncRNA,circRNA,microRNA,methylation of RNA and DNA,histone acetylation and pathological processes,include autophagy,fibrosis and apoptosis of LECs also involved i

关键词： Oxidative stress Epigenetic regulation Autophagy Fibrosis Apoptosis Diabetic cataract

Short-term effects of intravitreal Conbercept injection combined with laser photocoagulation on macular edema secondary to ischemic retinal vein occlusion

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International Journal of Ophthalmology(English edition) 2021年第5期14卷 732-736页

作者： Zheng-Feng Liu Xing-Rong Wang Xiao-Yan zhang xue-Mei Pan rui-xue zhang Hong-Sheng Bi Ying Wen Medical School of Ophthalmology&Optometry Shandong University of Traditional Chinese MedicineJinan 250355Shandong ProvinceChina Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine Jinan 250002Shandong ProvinceChina Shandong Provincial Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Diseases Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Diseases in Universities of ShandongEye Institute of Shandong University of Traditional Chinese MedicineJinan 250002Shandong ProvinceChina

AIM:To observe changes in the best-corrected visual acuity(BCVA),central macular thickness(CMT),and central choroidal thickness(CCT)of patients with macular edema(ME)secondary to ischemic retinal vein occlusion(i RVO)following intravitreal Conbercept ***:This retrospective study included 33 eyes from 33 patients who received intravitreal injections of Conbercept for ME secondary to i *** were performed on a 3+pro re nata(3+PRN)*** of the patients were examined by fundus fluorescein angiography and spectral domain optical coherence tomography at the first *** photocoagulation was performed in the nonperfusion area of the retina of all eyes after the first ***,CMT,and CCT were observed before and after 6 mo of *** number of injections necessary to achieve improved vision was also ***:Following Conbercept treatment,the mean BCVA significantly improved from 0.81±0.39 at baseline to 0.41±0.25 and 0.43±0.29 log MAR in the third and sixth months,respectively(both P=0.000).The CMT of the patients at baseline was 556.75±98.57μm;304.78±68.53 and 306.85±76.77μm 3 and 6 mo after treatment,respectively(both P=0.000 vs baseline).The CCTs of the patients at baseline,3 and 6 mo after treatment were 304.63±57.83,271.31±45.53,and 272.29±39.93μm,respectively(P=0.026 and 0.035 vs baseline).No severe adverse event relevant to the therapy was noted,and the average number of injections delivered was ***:Intravitreal Conbercept injection combined with laser photocoagulation appears to be a safe and effective treatment for ME secondary to i RVO in the short-term.

关键词： Conbercept laser photocoagulation macular edema ischemic retinal vein occlusion

TRPM3/miR-204复合位点调控眼部疾病的研究进展

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国际眼科杂志 2021年第5期21卷 800-804页

作者：张瑞雪何媛西安医学院中国陕西省西安市710016 西安医学院第二附属医院眼科中国陕西省西安市710038

微小RNA(micro RNA,miRNA)是最主要的基因表达调控因子之一,涉及多种细胞、组织和器官的生长、发育、分化及凋亡等过程。TRPM3基因位于人类9号染色体的长臂,是钙通透性离子通道TRP家族M亚家族中成员之一。miR-204位于TRPM3内含子6上,通... 详细信息

微小RNA(micro RNA,miRNA)是最主要的基因表达调控因子之一,涉及多种细胞、组织和器官的生长、发育、分化及凋亡等过程。TRPM3基因位于人类9号染色体的长臂,是钙通透性离子通道TRP家族M亚家族中成员之一。miR-204位于TRPM3内含子6上,通过对靶mRNAs的切割或抑制其翻译参与转录后基因表达的调控。研究显示TRPM3/miR-204复合位点在白内障、青光眼、角膜新生血管、角膜损伤愈合、视网膜疾病、视神经疾病等眼部疾病的发生发展中起着重要的调控作用。本文从TRPM3/miR-204分子通路的生物学功能、在眼部的表达与调控以及其与多种眼部疾病的相关性研究进展进行综述。

关键词： TRPM3 micro RNA 眼部疾病基因表达调控

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综合聚类和上下文特征的高光谱影像分类

武汉大学学报（信息科学版） 2017年第7期42卷 890-896页

作者：鲍蕊薛朝辉张像源苏红军杜培军天津市地质调查研究院天津300191 南京大学卫星测绘技术与应用国家测绘地理信息局重点实验室江苏南京210023 南京大学江苏省地理信息技术重点实验室江苏南京210023 河海大学地球科学与工程学院江苏南京210098

常规高光谱影像逐像素分类往往没有考虑空间相关性,分类结果未体现地物的空间关联和分布特征。为了在分类中充分利用空间特征,利用聚类信息并结合隐马尔可夫随机场模型讨论了高光谱遥感影像光谱-空间分类方法。首先,在不同特征提取方法... 详细信息

常规高光谱影像逐像素分类往往没有考虑空间相关性,分类结果未体现地物的空间关联和分布特征。为了在分类中充分利用空间特征,利用聚类信息并结合隐马尔可夫随机场模型讨论了高光谱遥感影像光谱-空间分类方法。首先,在不同特征提取方法(最小噪声分离、独立成分分析和主成分分析)下,使用不同聚类方法(k-均值、迭代自组织分析算法和模糊c-均值算法)借助隐马尔可夫随机场获取优化的分割图;然后,采用4连通区域标记法对分割区域标记生成图像对象,并根据支持向量机的逐像素分类结果采用多数投票法对图像对象进行分类;最后,借助凹槽窗口邻域滤波技术改进分类结果,削弱"椒盐"现象。该方法综合了监督分类和非监督分类的优势,通过聚类引入地物空间相关性信息,通过隐马尔可夫随机场引入上下文特征,较好地弥补了单纯基于光谱信息分类的不足。

关键词：聚类隐马尔可夫随机场支持向量机高光谱影像光谱-空间分类多数投票

Common susceptibility loci in both systemic sclerosis and localized scleroderma identified using genetic analysis

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Chinese Medical Journal 2020年第19期133卷 2370-2372页

作者： Yun Li Wen-Jun Wang Wei-Wei Chen xue Fan Lu Cao Ze-Yu Xing Qi Zhen Qiong-Qiong Xu Chen-Yu Zhu Hui-Yao Ge Dian Chen rui-xue zhang Chang Shu Wei Du Shi-rui Chen Xie Yuan Hui zhang Xia Hu Xu-Ming Mao Qiu-Ning Sun Department of Dermatology Beijing Tian Tan HospitalCapital Medical UniversityBeijing 100059China Department of Dermatology No.1 HospitalAnhui Medical UniversityHefeiAnhui 230022China Department of Dermatology Chinese Academy of Medical Sciences Peking Union Medical CollegePeking Union Medical College HospitalBeijing 100730China Department of Dermatology University of PennsylvaniaPhiladelphiaPA 19104USA.

Scleroderma is an autoimmune fibrosing disorder that can be further subclassified as localized scleroderma(LSc)and systemic sclerosis(SSc).LSc is characterized by sclerotic and pigmented skin lesions,while SSc is a more generalized disorder of the connective tissue involving a number of *** is characterized by the thickening of dermal collagen bundles,fibrosis,and vascular abnormalities in the visceral organs.[1]Despite the differences in their morphologic features and clinical presentation,these two diseases do share some characteristics including endothelial cell dysfunction,T helper 2(Th2)cell dominance during immune activation and excess fibrosis of the skin with similar pathologic findings,leading to the hypothesis that SSc and LSc share an underlying mechanism of ***,multiple lines of evidence suggest that genetic factors may contribute to SSc susceptibility.

关键词： organs susceptibility spite

影像学技术应用于阿尔茨海默病早期诊断的研究进展

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中国康复理论与实践 2017年第5期23卷 534-538页

作者：黄蕊华学思张兰首都医科大学宣武医院药物研究室北京市神经药物工程研究中心北京脑重大疾病研究院神经变性病教育部重点实验室北京市100053

对阿尔茨海默病(AD)的临床诊断主要根据临床病史,但敏感性和准确性有限。正电子发射计算机断层显像技术可通过葡萄糖代谢成像以及生物标记物成像较为准确地早期诊断AD;磁共振成像技术则通过结构成像以及功能成像,为AD的早期诊断和鉴别... 详细信息

对阿尔茨海默病(AD)的临床诊断主要根据临床病史,但敏感性和准确性有限。正电子发射计算机断层显像技术可通过葡萄糖代谢成像以及生物标记物成像较为准确地早期诊断AD;磁共振成像技术则通过结构成像以及功能成像,为AD的早期诊断和鉴别诊断提供基础。近年来,多模态成像技术将放射学与核医学紧密结合,可更为准确地诊断AD。

关键词：阿尔茨海默病正电子发射型计算机断层显像技术磁共振成像示踪剂综述

窄谱中波紫外线对银屑病皮损热休克蛋白27、60、90α、90β影响的研究

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医学与哲学（B） 2016年第10期37卷 62-65页

作者：张瑞雪张庆瑞戴逸楠牟村锦州医科大学辽宁锦州121000 解放军第202医院辽宁沈阳110003

探讨窄谱中波紫外线(NB-UVB)局部照射治疗银屑病患者前后,对皮损组织HSP27、HSP60、HSP90α、HSP90β表达的影响。采用免疫组化法检测20例银屑病患者皮损区治疗前后及10例正常人皮肤中HSP27、HSP60、HSP90α、HSP90β的表达情况。发现... 详细信息

探讨窄谱中波紫外线(NB-UVB)局部照射治疗银屑病患者前后,对皮损组织HSP27、HSP60、HSP90α、HSP90β表达的影响。采用免疫组化法检测20例银屑病患者皮损区治疗前后及10例正常人皮肤中HSP27、HSP60、HSP90α、HSP90β的表达情况。发现在银屑病皮损中,HSP60、HSP90α、HSP90β表达明显升高,与健康对照组比较,差异有统计学意义(P0.05)与治疗前比较,差异有统计学意义(P<0.05)。在银屑病皮损中,HSP27表达降低,与健康对照组比较,差异有统计学意义(P<0.05),NBUVB治疗后表达虽有所升高,但与健康对照组比较,差异仍有统计学意度(P<0.05);与治疗前比较,差异有统计学意义(P<0.05)。热休克蛋白在银屑病的发病过程中具有重要作用,并且不同的热休克蛋白在银屑病的发生发展中发挥的作用不尽相同。NB-UVB可通过调控热休克蛋白的表达,对银屑病起到有效的治疗作用。

关键词：银屑病热休克蛋白窄谱中波紫外线

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青少年学生心理资本与生活事件相关性分析

中国现代医学杂志 2017年第5期27卷 112-116页

作者：刘丽张瑞雪刘堃锦州医科大学护理学院辽宁锦州121001

目的了解青少年学生心理资本与自评负性生活事件严重程度(以下简称生活事件)现状,分析两者之间的相关性为进行有效的健康干预提供依据。方法采用便利、随机、分层及整群抽样相结合的方法运用青少年自评生活事件量表和心理资本问卷对1 10... 详细信息

目的了解青少年学生心理资本与自评负性生活事件严重程度(以下简称生活事件)现状,分析两者之间的相关性为进行有效的健康干预提供依据。方法采用便利、随机、分层及整群抽样相结合的方法运用青少年自评生活事件量表和心理资本问卷对1 100例学生进行问卷调查。结果心理资本总分和自信与生活事件总分、人际关系、学习压力、受处罚、健康适应和其他维度均呈负相关,相关系数为-0.217^-0.092;韧性与生活事件总分、人际关系、学习压力、健康适应和其他维度均呈负相关相关系数为-0.189^-0.073。生活事件严重等级不同的学生心理资本得分不同;多元回归结果显示,自信维度是生活事件及其各维度的控制变量。结论心理资本和自评生活事件严重程度有关,针对经历不同生活事件的学生提供有效的个体化干预,提高学生的心理资本可增强其应对生活事件的能力。

关键词：青少年学生生活事件心理资本