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距骨不同区域骨小梁形态特征的Micro-CT评估
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作者 李磊 张凤珍 +10 位作者 尹兆正 伊钰营 申晓科 段博 王志强 任小燕 李琨 李志军 王奇娇 王星 张少杰 《中国组织工程研究》 北大核心 2026年第15期3946-3952,共7页
背景:距骨骨折治疗难度大,易出现多种并发症,导致预后不良,故需进一步了解距骨内骨小梁分布特征及其与骨折发生的关系。目的:利用Micro-CT技术对距骨标本进行扫描,观测骨小梁结构特征及形态计量学参数,探讨距骨不同区域的骨小梁差异,为... 背景:距骨骨折治疗难度大,易出现多种并发症,导致预后不良,故需进一步了解距骨内骨小梁分布特征及其与骨折发生的关系。目的:利用Micro-CT技术对距骨标本进行扫描,观测骨小梁结构特征及形态计量学参数,探讨距骨不同区域的骨小梁差异,为距骨骨折的预防、治疗及骨折机制研究提供依据。方法:选取53例成人距骨标本进行Micro-CT扫描,将影像资料导入Avata软件进行三维重建,通过对距骨头部、颈部、体部3个感兴趣区域内骨小梁的勾选与重建,观察其形态特征,并测量分析不同区域骨小梁形态计量学参数的差异。结果与结论:①距骨的Micro-CT扫描影像显示其头部和体部的皮质骨较薄,而颈部的皮质骨则相对较厚;颈部的骨小梁分布较为稀疏,而头部和体部的骨小梁则相对致密;②距骨骨小梁的骨体积、骨体积分数、骨小梁模式因子在头部与颈部、体部间比较差异均有显著性意义(P<0.05);距骨骨小梁的骨表面积、骨表面积组织体积比、骨小梁分离度、分形维数在颈部与头部、体部间比较差异均有显著性意义(P<0.05);距骨骨小梁的骨小梁厚度在体部与头部、颈部之间比较差异有显著性意义(P<0.05);距骨骨小梁的骨表面积骨体积比、骨小梁厚度、骨小梁连通性、骨小梁连接密度、各向异性程度、结构模型指数在颈部与头部、体部,头部与体部间比较差异均有显著性意义(P<0.05);③提示Micro-CT技术能够定量分析距骨不同区域骨小梁形态的计量学参数,距骨的骨小梁形态计量学参数存在区域性差异,颈部的骨小梁数量和强度较低,是最容易发生骨折的部位,从骨小梁分布特征说明了距骨骨折好发于颈部。 展开更多
关键词 距骨 micro-ct 骨小梁 区域差异 形态计量学参数
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Therapeutic effects of low-intensity transcranial focused ultrasound stimulation on ischemic stroke in rats:An in vivo evaluation using electrical impedance tomography
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作者 Jiecheng Guo Sixuan He +4 位作者 Li Yan Lei Wang Xuetao Shi Huijing Hu Le Li 《Neural Regeneration Research》 2026年第3期1183-1190,共8页
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to... Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke. 展开更多
关键词 animal model brain stimulation electrical impedance tomography evaluation impedance noninvasive treatment real-time monitoring REHABILITATION STROKE transcranial focused ultrasound stimulation
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基于Micro-CT分析大豆种子结构表型及构建种子重量预测模型 被引量:1
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作者 刘长斌 李远鲲 +3 位作者 郭民坤 樊江川 郭新宇 卢宪菊 《大豆科学》 北大核心 2025年第1期11-21,共11页
大豆是重要的粮油兼用作物,是植物蛋白质的重要来源,为明确大豆种子结构特征并构建种子重量预测模型,以42个不同大豆品种为材料,利用Micro-CT技术扫描测试样本,通过CT图像的处理解析,获取大豆种子的长度、宽度、厚度、体积、表面积、种... 大豆是重要的粮油兼用作物,是植物蛋白质的重要来源,为明确大豆种子结构特征并构建种子重量预测模型,以42个不同大豆品种为材料,利用Micro-CT技术扫描测试样本,通过CT图像的处理解析,获取大豆种子的长度、宽度、厚度、体积、表面积、种胚体积、表面积及空腔体积特征,人工称重测定单粒重量指标。系统分析种子形态特征及其与重量的相关关系,并对不同品种进行聚类分析,通过对多项形态表型和重量指标进行主成分分析,确定主要贡献指标,基于机器学习算法构建重量预测模型。结果表明:种子形态特征与种子重量显著相关,但种子形状特征对重量无显著影响;42个大豆品种可以分为4类,其中第一类品种蒙豆375和蒙豆60的种子大小和重量指标均显著高于其他3类品种。利用随机森林模型和偏最小二乘回归方法构建的重量预测模型效果优于单一指标的简单线性回归效果。其中,随机森林回归模型训练集和测试集的R^(2)分别为0.80和0.66,RMSE分别为0.017和0.021 g,偏最小二乘回归模型训练集和测试集的R^(2)分别为0.75和0.72,RMSE分别为0.019和0.020 g。研究结果为大豆种子外部形态和内部结构的研究提供了新的技术和方法,为大豆品种分类、产量和品质性状的评价提供理论和技术参考。 展开更多
关键词 micro-ct 大豆 结构表型 重量预测 模型构建 机器学习
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基于Micro-CT的土壤结构变化三维可视化量化表征方法
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作者 仲伟正 史卓林 +3 位作者 张合虎 康子涵 杨增玲 韩鲁佳 《农业机械学报》 北大核心 2025年第7期653-661,678,共10页
机械压实是导致土壤结构和功能改变,进而制约农业可持续发展的重要因素之一。本文采集砂土、壤土和粘土3种不同质地土壤,采用机械加压方式模拟制备了不同压实程度的土壤样品,并使用先进的Skyscan 1275 MicroCT系统进行样品扫描。比较了... 机械压实是导致土壤结构和功能改变,进而制约农业可持续发展的重要因素之一。本文采集砂土、壤土和粘土3种不同质地土壤,采用机械加压方式模拟制备了不同压实程度的土壤样品,并使用先进的Skyscan 1275 MicroCT系统进行样品扫描。比较了主动轮廓(AC)、标记分水岭(MBW)和K-means 3种不同算法对土壤孔隙和团聚体结构样品Micro-CT图像的分割效果,结果表明K-means图像分割算法最优。采用形态学分水岭算法和Canny边缘检测算法有效实现了土壤团聚体和孔隙个体的原位分离。基于K-means分割算法,优化提出了一种土壤物理结构Micro-CT原位、三维、可视化量化表征方法,原位三维可视化呈现了不同压实土壤样品孔隙和团聚体结构分布量化信息。Micro-CT成像表征结果与实验室分析结果具有很好的一致性。研究结果为土壤压实以及土壤结构数字化图谱等相关研究提供了快速分析方法。 展开更多
关键词 土壤压实 micro-ct 三维可视化 土壤结构 图像分割
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IN VIVO VALIDATION OF DUAL-MODALITY SYSTEM FOR SIMULTANEOUS POSITRON EMISSION TOMOGRAPHY AND OPTICAL TOMOGRAPHIC IMAGING
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作者 XIN WANG BIN ZHANG +4 位作者 XU CAO FEI LIU SHUANGQUAN LIU BAOCI SHAN JING BAI 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第2期165-171,共7页
We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast canc... We report on tests of combined positron emission tomography(PET)andfluorescence molecular tomography(FMT)imaging system for in vivo investigation on small animals.A nude mouse was inoculated with MD-MB-231 breast cancer cells which expressed redfluorescent protein(RFP).For FMT system,reflective illumination mode was adopted with full-angle data acquisition.[18F]-Fluorodeoxyglucose([18F]-FDG)was used as radioactive tracer for PET.Both data were acquired simultaneously and then reconstructed separately before fusion.Fluorescent tomography results showed exactly where the tumor was located while PET results offered more metabolic information.Results confirmed feasibility for tumor detection and showed superiority to single modality imaging. 展开更多
关键词 Dual-modality imaging positron emission tomography fluorescence molecular tomography
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基于计算视觉技术的固体推进剂Micro-CT数据挖掘算法
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作者 韩嘉禾 李濮舟 +4 位作者 文明杰 马金羽 王小英 初庆钊 陈东平 《固体火箭技术》 北大核心 2025年第3期450-460,共11页
固体推进剂内部微观结构复杂、组分分布多样,基于Micro-CT推进剂图像的数据分析与挖掘存在较大挑战。为此,构建了一种高效、准确的图像分析方法,以深入挖掘固体推进剂Micro-CT图像数据,推动微观结构与性能关联机制的研究。采用高分辨率M... 固体推进剂内部微观结构复杂、组分分布多样,基于Micro-CT推进剂图像的数据分析与挖掘存在较大挑战。为此,构建了一种高效、准确的图像分析方法,以深入挖掘固体推进剂Micro-CT图像数据,推动微观结构与性能关联机制的研究。采用高分辨率Micro-CT扫描两种推进剂样品,通过图像预处理、组分识别、密度估算和粒径分析等关键步骤,提取了推进剂密度、高氯酸铵(AP)颗粒粒径分布及各组分的空间分布特征,实现了推进剂内部微观结构的定量表征。结果表明,提出的图像分析算法能够精准识别推进剂内部主要成分,并提供可靠的密度(误差≤5%)和粒径评估(误差≤8%)结果。此外,研究对推进剂组分质心分布及其径向分布特征进行了定量分析,评估了各组分在基体中的分散/团聚状态,为推进剂配方优化、界面结合研究及贮存寿命评估提供了数据支持,为深入理解推进剂微观结构对性能的影响提供了科学依据。 展开更多
关键词 固体推进剂 micro-ct 数据挖掘 微观结构
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Role of photon-counting computed tomography in pediatric cardiovascular imaging 被引量:1
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作者 Arosh S Perera Molligoda Arachchige Yash Verma 《World Journal of Clinical Pediatrics》 2025年第1期55-62,共8页
Photon-counting computed tomography(PCCT)represents a significant advancement in pediatric cardiovascular imaging.Traditional CT systems employ energy-integrating detectors that convert X-ray photons into visible ligh... Photon-counting computed tomography(PCCT)represents a significant advancement in pediatric cardiovascular imaging.Traditional CT systems employ energy-integrating detectors that convert X-ray photons into visible light,whereas PCCT utilizes photon-counting detectors that directly transform X-ray photons into electric signals.This direct conversion allows photon-counting detectors to sort photons into discrete energy levels,thereby enhancing image quality through superior noise reduction,improved spatial and contrast resolution,and reduced artifacts.In pediatric applications,PCCT offers substantial benefits,including lower radiation doses,which may help reduce the risk of malignancy in pediatric patients,with perhaps greater potential to benefit those with repeated exposure from a young age.Enhanced spatial resolution facilitates better visualization of small structures,vital for diagnosing congenital heart defects.Additionally,PCCT’s spectral capabilities improve tissue characterization and enable the creation of virtual monoenergetic images,which enhance soft-tissue contrast and potentially reduce contrast media doses.Initial clinical results indicate that PCCT provides superior image quality and diagnostic accuracy compared to conven-tional CT,particularly in challenging pediatric cardiovascular cases.As PCCT technology matures,further research and standardized protocols will be essential to fully integrate it into pediatric imaging practices,ensuring optimized diagnostic outcomes and patient safety. 展开更多
关键词 CARDIOVASCULAR Photon-counting detectors PEDIATRIC Photon-counting computed tomography Computed tomography
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micro-CT和有限元分析技术在手舟骨研究中的应用进展
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作者 吕远 张德洲 +11 位作者 钱海龙 王思敏 王超群 李琨 陈杰 白雪 赵海龙 张少杰 马渊 李志军 史君 王星 《局解手术学杂志》 2025年第2期168-173,共6页
手舟骨是手部的重要骨骼之一,在临床上损伤频发且治疗具有一定难度。因此,深入研究手舟骨的微观结构和生物力学特征对了解其损伤机制和优化治疗方案至关重要。微计算机断层扫描(micro-CT)技术提供了高分辨率的骨组织成像,而有限元分析... 手舟骨是手部的重要骨骼之一,在临床上损伤频发且治疗具有一定难度。因此,深入研究手舟骨的微观结构和生物力学特征对了解其损伤机制和优化治疗方案至关重要。微计算机断层扫描(micro-CT)技术提供了高分辨率的骨组织成像,而有限元分析则能帮助模拟手舟骨在不同生理和病理状态下的应力分布和行为模式。通过micro-CT技术获取手舟骨的高分辨率三维图像,能够用于构建手舟骨真实解剖结构的有限元模型,从而实现对手舟骨力学性能的精确模拟。这两种先进技术的融合为揭示手舟骨的结构功能关系及其损伤机制提供了新视角。因此,本文回顾了手舟骨的解剖学特征及其在不同状态下的生物力学行为,并重点讨论了micro-CT和有限元分析技术在手舟骨研究中的具体应用及其优势,通过综述近几年来的研究成果,为手舟骨相关疾病的诊断、治疗及预防提供新的科学依据和方法。 展开更多
关键词 手舟骨 微观结构 生物力学 micro-ct 有限元分析 基础研究 临床研究 研究进展
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基于Micro-CT技术的猪牛羊皮革内部结构分析
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作者 冯敏 杨海亮 +2 位作者 陈海相 岳亚雯 瞿金霞 《浙江理工大学学报(自然科学版)》 2025年第5期625-633,共9页
为无损观察并分析皮革的内部结构特征,首先采用微计算机断层扫描(Micro-computed Tomography,Micro-CT)获取猪、牛、羊皮革的二维图像,然后利用三维重构技术生成皮革的三维立体图像,最后通过Dragonfly软件的分割、增强和测量等图像处理... 为无损观察并分析皮革的内部结构特征,首先采用微计算机断层扫描(Micro-computed Tomography,Micro-CT)获取猪、牛、羊皮革的二维图像,然后利用三维重构技术生成皮革的三维立体图像,最后通过Dragonfly软件的分割、增强和测量等图像处理功能,对皮革样品进行任意虚拟切片处理,在不破坏样品的前提下,深入分析皮革内部的结构特征。结果表明:猪皮革内部的毛发毛囊以3个为1组,呈三角形排列;牛皮革纤维束粗大,乳头层与网状纤维层区分明显;羊皮革纤维束细小,毛发毛囊倾斜角度最小。猪、牛、羊皮革的不同毛发毛囊倾斜角度和深度的特征差异显著。该研究结果可为真皮革材质的鉴别提供基础数据和图像参考。 展开更多
关键词 micro-ct 皮革 三维结构 虚拟切片 毛囊
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Optical coherence tomography angiography in diabetic retinopathy:focusing on microvascular changes 被引量:4
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作者 Yang Xiongyi Yi Guoguo +5 位作者 Chen Yanxia Yang Siyu Ai Shibei Zheng Cong Cao Mingzhe Fu Min 《国际眼科杂志》 2025年第2期179-190,共12页
AIM:To investigate the value of optical coherence tomography angiography(OCTA)indicators in the diagnosis of diabetic retinopathy(DR),and to provide patients with diabetic nephropathy(DN)with more sensitive OCTA scree... AIM:To investigate the value of optical coherence tomography angiography(OCTA)indicators in the diagnosis of diabetic retinopathy(DR),and to provide patients with diabetic nephropathy(DN)with more sensitive OCTA screening indicators to detect concurrent DR at an early stage.METHODS:A total of 200 patients who treated in the ophthalmology department of the Seventh Affiliated Hospital,Sun Yat-sen University from 2022 to 2023 were included,including 95 first-diagnosed DR patients and 105 patients without DR,and all patients underwent OCTA examination and a collection of demographics and renal function parameters.After a quality check,automated measurements of the foveal avascular zone area,vessel density(VD),and perfusion density(PD)of both 3 mm×3 mm and 6 mm×6 mm windows were obtained.RESULTS:Using random forest and multivariate Logistic regression methods,we developed a diagnostic model for DR based on 12 variables(age,FBG,SBP,DBP,HbA1c,ALT,ALP,urea/Scr,DM duration,HUA,DN,and CMT).Adding specific OCTA parameters enhanced the efficacy of the existing diagnostic model for DR(outer vessel density in 6 mm×6 mm window,AUC=0.837 vs 0.819,P=0.03).In the study of DN patients,the parameters in the 6 mm×6 mm window improved the diagnostic efficacy of DR(inner VD;outer VD;full VD;outer PD;full PD).CONCLUSION:The outer VD in the 6 mm×6 mm window can enhance the efficacy of the traditional DR diagnostic model.Meanwhile,compared with the 3 mm×3 mm window,the microvascular parameters in the 6 mm×6 mm window focusing on DN patients can be more sensitive to diagnosing the occurrence of DR. 展开更多
关键词 optical coherence tomography angiography(OCTA) diabetic retinopathy diabetic nephropathy prediction model
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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism 被引量:1
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作者 Yujie Yang Xinyi Li +7 位作者 Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo 《Neural Regeneration Research》 SCIE CAS 2025年第1期93-106,共14页
Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.... Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders. 展开更多
关键词 aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease PARKINSONISM positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2
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基于Micro-CT的针刺陶瓷基复合材料缺陷微观结构重构与表征
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作者 何乾强 刘明刚 +1 位作者 李嘉旺 孙士勇 《机械设计与制造工程》 2025年第5期29-33,共5页
针刺陶瓷基复合材料在航空航天等领域具有广阔的应用前景。针对针刺陶瓷基复合材料内部存在的微观缺陷,采用Micro-CT技术进行高精度检测,从微观层面观测分析针刺陶瓷基复合材料内部孔隙、纤维偏转和裂纹等缺陷。借助三维重构技术重构基... 针刺陶瓷基复合材料在航空航天等领域具有广阔的应用前景。针对针刺陶瓷基复合材料内部存在的微观缺陷,采用Micro-CT技术进行高精度检测,从微观层面观测分析针刺陶瓷基复合材料内部孔隙、纤维偏转和裂纹等缺陷。借助三维重构技术重构基体和纤维结构,分析了孔隙的分布特点和各区域孔隙的形成机理。基于孔隙形态结构,对孔隙分布位置与形态差异进行了准确表征,为进一步揭示材料内部微观缺陷对复合材料性能的影响奠定了基础。 展开更多
关键词 针刺陶瓷基复合材料 微观缺陷 micro-ct检测 缺陷表征
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Macular microvascular and structural changes on optical coherence tomography angiography in atypical optic neuritis 被引量:1
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作者 Chinmay Mahatme Madhurima Kaushik +2 位作者 Veerappan Rathinasabapathy Saravanan Karthik Kumar Virna M Shah 《World Journal of Methodology》 2025年第1期88-94,共7页
BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic im... BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic implications and longterm management strategies.Vascular and metabolic factors are being thought to play a role in such autoimmune neuro-inflammatory disorders,apart from the obvious immune mediated damage.With the advent of optical coherence tomography angiography(OCTA),it is easy to pick up on these subclinical macular microvascular and structural changes.AIM To study the macular microvascular and structural changes on OCTA in atypical optic neuritis.METHODS This observational cross-sectional study involved 8 NMOSD and 17 MOGAD patients,diagnosed serologically,as well as 10 healthy controls.Macular vascular density(MVD)and ganglion cell+inner plexiform layer thickness(GCIPL)were studied using OCTA.RESULTS There was a significant reduction in MVD in NMOSD and MOGAD affected as well as unaffected eyes when compared with healthy controls.NMOSD and MOGAD affected eyes had significant GCIPL thinning compared with healthy controls.NMOSD unaffected eyes did not show significant GCIPL thinning compared to healthy controls in contrast to MOGAD unaffected eyes.On comparing NMOSD with MOGAD,there was no significant difference in terms of MVD or GCIPL in the affected or unaffected eyes.CONCLUSION Although significant microvascular and structural changes are present on OCTA between atypical optic neuritis and normal patients,they could not help in differentiating between NMOSD and MOGAD cases. 展开更多
关键词 Optical coherence tomography angiography Atypical optic neuritis Macular microvascular changes Neuromyelitis optica spectrum disorders Myelin oligodendrocyte glycoprotein antibody disorder
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Renal angiomyolipomas:Typical and atypical features on computed tomography and magnetic resonance imaging 被引量:1
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作者 Andres Labra Giancarlo Schiappacasse +1 位作者 Diego Constenla Joaquin Cristi 《World Journal of Radiology》 2025年第2期11-20,共10页
Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is... Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is to discuss computed tomography(CT)and magnetic resonance imaging findings for both typical and atypical renal AMLs,along with their associated complications.AMLs are typically defined as solid triphasic tumors composed of varying amounts of dysmorphic and tortuous blood vessels,smooth muscle components and adipose tissue.In an adult,a classical renal AML appears as a solid,heterogeneous renal cortical mass with macroscopic fat.However,up to 5%of AMLs contain minimal fat and cannot be reliably diagnosed by imaging.Fat-poor AMLs can appear as hyperattenuating masses on unenhanced CT and as hypointense masses on T2WI;other AMLs may be isodense or exhibit cystic components.Hemorrhage is the most common complication,and AMLs with hemorrhage can mimic other tumors,making their diagnosis challenging.Understanding the variable and heterogeneous nature of this neoplasm to correctly classify renal AMLs and to avoid misdiagnosis of other renal lesions is crucial. 展开更多
关键词 Kidney neoplasms ANGIOMYOLIPOMA Classic angiomyolipoma-fat poor angiomyolipoma tomography X-ray computed Magnetic resonance imaging
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Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography
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作者 WU Min CAO Kailei +4 位作者 XIAO Weirong YU Zetai CAO Jierong DING Qingjun LI Jinhui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期164-170,共7页
The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an ... The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution. 展开更多
关键词 CONCRETE external sulfate attack damage evolution situ X-ray computed tomography
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3D tomographic analysis of equatorial plasma bubble using GNSS-TEC data from Indonesian GNSS Network
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作者 Ihsan Naufal Muafiry Prayitno Abadi +5 位作者 Teguh N.Pratama Dyah R.Martiningrum Sri Ekawati Yuandhika GWismaya Febrylian FChabibi Gatot HPramono 《Earth and Planetary Physics》 EI CAS 2025年第1期127-136,共10页
Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other s... Equatorial Plasma Bubbles(EPBs)are ionospheric irregularities that take place near the magnetic equator.EPBs most commonly occur after sunset during the equinox months,although they can also be observed during other seasons.The phenomenon significantly disrupts radio wave signals essential to communication and navigation systems.The national network of Global Navigation Satellite System(GNSS)receivers in Indonesia(>30°longitudinal range)provides an opportunity for detailed EPB studies.To explore this,we conducted preliminary 3D tomography of total electron content(TEC)data captured by GNSS receivers following a geomagnetic storm on December 3,2023,when at least four EPB clusters occurred in the Southeast Asian sector.TEC and extracted TEC depletion with a 120-minute running average were then used as inputs for a 3D tomography program.Their 2D spatial distribution consistently captured the four EPB clusters over time.These tomography results were validated through a classical checkerboard test and comparisons with other ionospheric data sources,such as the Global Ionospheric Map(GIM)and International Reference Ionosphere(IRI)profile.Validation of the results demonstrates the capability of the Indonesian GNSS network to measure peak ionospheric density.These findings highlight the potential for future three-dimensional research of plasma bubbles in low-latitude regions using existing GNSS networks,with extensive longitudinal coverage. 展开更多
关键词 EPB Indonesian GNSS Network 3D tomography
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Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease
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作者 Hao Ding Yuan-Yuan Fang +5 位作者 Wen-Jie Fan Chen-Yu Zhang Shao-Fei Wang Jing Hu Wei Han Qiao Mei 《World Journal of Gastroenterology》 SCIE CAS 2025年第3期62-72,共11页
BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD patients.Yet,it poses a significan... BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD patients.Yet,it poses a significant challenge due to its limited accessibility through conventional endoscopic methods.AIM To establish a noninvasive radiomic model based on computed tomography enterography(CTE)for MH assessment in SBCD patients.METHODS Seventy-three patients diagnosed with SBCD were included and divided into a training cohort(n=55)and a test cohort(n=18).Radiomic features were obtained from CTE images to establish a radiomic model.Patient demographics were analysed to establish a clinical model.A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic features.The diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),respectively.RESULTS Of the 73 patients enrolled,25 patients achieved MH.The radiomic-clinical nomogram had an area under the ROC curve of 0.961(95%confidence interval:0.886-1.000)in the training cohort and 0.958(0.877-1.000)in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone,as demonstrated by DCA.CONCLUSION These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients. 展开更多
关键词 Crohn’s disease Computed tomography enterography Mucosal healing NOMOGRAM Radiomics
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Upper crustal azimuthal anisotropy and seismogenic tectonics of the Hefei segment of the Tan-Lu Fault Zone from ambient noise tomography 被引量:1
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作者 Cheng Li HuaJianYao +4 位作者 Song Luo HaiJiang Zhang LingLi Li XiaoLi Wang ShengJun Ni 《Earth and Planetary Physics》 2025年第2期253-265,共13页
The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structur... The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas. 展开更多
关键词 ambient noise tomography azimuthal anisotropy upper crust seismogenic structure the Tan-Lu Fault Zone Hefei segment
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3种根管封闭剂充填效果的Micro-CT评估
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作者 黄日鸿 曾祥倪 +3 位作者 蒋丽 张立霞 朱静雅 何飞 《华西口腔医学杂志》 北大核心 2025年第5期722-727,共6页
目的应用Micro-CT评价3种生物材料根管封闭剂iRoot SP、C-Root SP及GuttaFlow Bioseal(GFB)的根管充填效果。方法选取60颗单根单管离体前磨牙,截冠使工作长度统一为12 mm,机用镍钛根管预备至30号06锥度。样本随机分成6组,使用3种根管封... 目的应用Micro-CT评价3种生物材料根管封闭剂iRoot SP、C-Root SP及GuttaFlow Bioseal(GFB)的根管充填效果。方法选取60颗单根单管离体前磨牙,截冠使工作长度统一为12 mm,机用镍钛根管预备至30号06锥度。样本随机分成6组,使用3种根管封闭剂、2种充填法进行根管充填,分别为iRoot SP+单尖法充填、C-Root SP+单尖法充填、GFB+单尖法充填、iRoot SP+超声活化单尖法充填、C-Root SP+超声活化单尖法充填、GFB+超声活化单尖法充填。对充填样本进行Micro-CT扫描,Mimics 22.0软件进行根管系统三维重建,计算根管整体充填率及根冠1/3、根中1/3、根尖1/3的分段充填率。结果3种根管封闭剂的整体充填率均大于90%。单尖法根管充填时,GFB的根管整体充填率、根冠1/3及根中1/3段充填率均低于iRoot SP、C-Root SP(P<0.01),iRoot SP与C-Root SP充填率间的差异均无统计学意义(P>0.05)。超声活化单尖法根管充填时,GFB的根管整体充填率及各段充填率均低于iRoot SP、C-Root SP(P<0.01),iRoot SP与C-Root SP充填率间的差异均无统计学意义(P>0.05)。2种充填方法对比,除C-Root SP单尖法充填时根尖1/3充填率低于超声活化单尖法(P<0.01),GFB单尖法充填时根冠1/3充填率高于超声活化单尖法(P<0.01)外,其余充填率间的差异均无统计学意义(P>0.05)。结论3种生物材料根管封闭剂使用单尖法及超声活化单尖法充填根管的整体充填率良好,其中iRoot SP与C-Root SP的充填效果相似,相比GFB具有更好的充填质量。C-Root SP配合超声活化单尖法能提高根尖段充填率。 展开更多
关键词 根管充填 根管封闭剂 iRoot SP C-Root SP GuttaFlow Bi-oseal micro-ct
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Comparison of the effect of ranibizumab in retinal vein occlusion and macular edema with different optical coherence tomographic patterns 被引量:1
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作者 Yue Xu Yue-Cong Yin +3 位作者 Ze-Yu Song Xiao-Yu Zhou Jia-Ju Zhang Juan Liang 《International Journal of Ophthalmology(English edition)》 2025年第2期275-282,共8页
AIM:To explore the morphological and functional parameters to evaluate the effectiveness of intravitreal injections of ranibizumab(IVR)in treating macular edema(ME)secondary to retinal vein occlusion(RVO).METHODS:This... AIM:To explore the morphological and functional parameters to evaluate the effectiveness of intravitreal injections of ranibizumab(IVR)in treating macular edema(ME)secondary to retinal vein occlusion(RVO).METHODS:This retrospective study involved 65 RVO patients(65 eyes)who received IVR and were followedup for more than 3mo.ME was categorized into cystoid macular edema(CME),diffuse retinal thickening(DRT),and serous retinal detachment(SRD)according to optical coherence tomography(OCT)images.The comparison of best corrected visual acuity(BCVA;logMAR)and central macular thickness(CMT)among different follow-up points and those among 3 groups were performed by Kruskal-Wallis test.The correlation between BCVA and baseline parameters during treatment was analyzed using Spearman correlation analysis.RESULTS:BCVA tended to improve in all groups,with marked improvement in CME and DRT groups.CMT showed the greatest reduction after 1wk,and remained stable over the following 3mo.DRT patients had the worst BCVA and the highest CMT at baseline,but the differences became smaller after IVR treatment.CMT in SRD group was significantly better than in CME and DRT groups 3mo after IVR.Most patients of CME and SRD groups transitioned to a normal pattern at 3mo follow-up.DRT patients were most likely to transform into the other morphological groups,while SRD patients showed minimal transitions.BCVA at baseline was identified as the most important prognostic indicator in all 3 groups.Additionally,DRT patients with a longer clinical course,higher CMT and central retinal vein occlusion(CRVO)tend to exhibit worse BCVA after treatment.In addition,CRVO patients are more likely to have worse BCVA at 2 and 3mo follow-up compared with branch retinal vein occlusion(BRVO)patients in CME group.SRD patients with higher baseline CMT were prone to experiencing worse BCVA after treatment.CONCLUSION:The effectiveness of IVR is strongly correlated with baseline BCVA in all 3 groups.Baseline parameters including clinical course,CMT,and RVO position are also useful in predicting the BCVA at different time points after treatment. 展开更多
关键词 retinal vein occlusion optical coherence tomography serous retinal detachment cystoid macular edema diffuse retinal thickening
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