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3.0T磁共振T2 mapping序列联合血清新饱食分子蛋白1水平检测在老年膝关节早期骨关节炎诊断中的应用价值
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作者 唐利 巩玉荣 +2 位作者 曾立叶 高艳芳 邓成哲 《实用医学杂志》 北大核心 2025年第8期1238-1242,共5页
目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据... 目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据X线结果将膝关节OA组分为早期组和非早期组,均接受3.0T MRI T2 mapping序列扫描检测膝关节软骨区域T2值,检测血清nesfatin-1水平,比较上述指标差异并采用ROC曲线分析其对老年膝关节早期OA的诊断价值。结果97例老年膝关节OA患者中,早期组35例,非早期组62例,OA组患者膝关节5个软骨区域的T2值及nesfatin-1血清均高于对照组(P<0.05),早期组均低于非早期组(P<0.05);膝关节软骨区域T2值和血清nesfatin-1水平单独诊断早期OA的AUC在0.774~0.871范围,联合诊断的AUC为0.939。结论3.0 T磁共振T2 mapping序列联合血清nesfatin-1水平检测对老年膝关节早期OA具有较高的诊断价值。 展开更多
关键词 膝关节早期骨关节炎 老年 磁共振 T2 mapping序列 新饱食分子蛋白1
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心脏磁共振T1 mapping在心肌病的应用及成像技术进展
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作者 邓佳 唐惠芳 +4 位作者 周宏 余莹 杨雯敏 周锦标 田进伟 《中国动脉硬化杂志》 2025年第2期154-162,共9页
随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临... 随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临床作用。本文旨在全面介绍T1 mapping在心肌病患者中的临床应用,归纳常用的扫描技术及其成像原理。 展开更多
关键词 心脏磁共振 T1 mapping 心肌病
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钆塞酸二钠增强MRI T1 mapping技术在肝细胞癌病理分级中的定量评估价值
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作者 韦孟 李光耀 +1 位作者 吴树剑 刘希胜 《齐齐哈尔医学院学报》 2025年第7期650-656,共7页
目的 探讨基于肝脏特异性对比剂钆塞酸二钠(Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid, Gd-EOB-DTPA)增强MRI T1mapping技术的定量参数在评估肝细胞癌(Hepatocellular carcinoma, HCC)病理分级中的价值。方法 选择2... 目的 探讨基于肝脏特异性对比剂钆塞酸二钠(Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid, Gd-EOB-DTPA)增强MRI T1mapping技术的定量参数在评估肝细胞癌(Hepatocellular carcinoma, HCC)病理分级中的价值。方法 选择2018年1月—2022年12月本院收治的34例HCC患者作为研究对象,根据Edmondson-Steiner病理分级标准,按病灶分为低级别组(Ⅰ~Ⅱ级)和高级别组(Ⅲ~Ⅳ级)两组,低级别组19例,高级别组15例。所有患者均接受平扫期和肝胆特异期的T1mapping成像。测量肿瘤实质、肿瘤整体、瘤周1cm区域及正常肝实质的T1弛豫时间。结合红细胞压积水平,计算肿瘤实质和肿瘤整体的细胞外容积分数(Extracellular volume, ECV)。比较各定量参数间的组间差异,并评估具有统计学意义的定量参数与病理分级的相关性。对于显著相关的指标,使用受试者工作特征(Receiver operating characteristic, ROC)曲线和曲线下面积(Area under the curve, AUC)评估其效能。结果 高级别组患者的肿瘤长径、瘤周1 cm增强前T1弛豫时间(T1pre)、肿瘤实质T1pre值、肿瘤实质增强后肝胆特异期T1弛豫时间(T1post)及肿瘤整体T1pre值均高于低级别组,差异具有统计学意义(P<0.05);相关性分析显示,病灶长径、瘤周1 cm T1pre值、肿瘤实质T1pre值、肿瘤实质T1post值及肿瘤整体T1pre值与HCC病理分级呈正相关(r=0.47、0.39、0.38、0.40、0.37,P均<0.05),其诊断效能AUC分别为0.758、0.726、0.709、0.719、0.691,联合模型的AUC为0.870。结论 基于Gd-EOB-DTPA增强MRI T1mapping技术的定量评估在HCC病理分级中具有重要价值。 展开更多
关键词 钆塞酸二钠 磁共振成像 T1 mapping 肝细胞癌 肿瘤分级
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Fine mapping of Pm71,a novel powdery mildew resistance gene from emmer wheat 被引量:2
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作者 Jiadong Zhang Hong Yang +10 位作者 Guohao Han Hongxing Xu Ruishan Liu Ningning Yu Ran Han Yaoxue Li Jiatong Li Yintao Dai Cheng Liu Yuli Jin Pengtao Ma 《The Crop Journal》 2025年第1期62-68,共7页
Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage... Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage resistance to powdery mildew over consecutive years.Genetic analysis of H1-707 at the seedling stage revealed a dominant monogenic inheritance pattern,and the underlying gene was designated Pm71.By employing bulked segregant exome sequencing(BSE-Seq)and using 2000 F2:3 families,Pm71 was fine mapped to a 336-kb interval on chromosome arm 6AS by referencing to the durum cv.Svevo RefSeq 1.0.Collinearity analysis revealed high homology in the candidate interval between Svevo and six Triticum species.Among six high-confidence genes annotated within this interval,TRITD6Av1G005050 encoding a GDSL esterase/lipase was identified as a key candidate for Pm71. 展开更多
关键词 Blumeria graminis BSE-Seq Disease resistance Fine mapping Triticum dicoccum
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基于T2^(*)mapping的业余马拉松运动员足踝部关节软骨损伤及其影响因素分析
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作者 高雅丽 兰晓川 +2 位作者 王舒 宋凌恒 陈伟 《磁共振成像》 北大核心 2025年第2期94-99,共6页
目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,... 目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,其中跑量<300 km/月的36例(中低跑量组),跑量≥300 km/月的12例(高跑量组)。所有受试者均进行单侧无症状踝关节的MRI扫描,扫描序列包括T2^(*)mapping多回波自旋回波(spin echo,SE)序列矢状位、质子密度加权成像脂肪抑制(proton density-weighted imaging fat-saturated,PDWI-FS)序列矢状位、冠状位、横轴位以及T1加权脂肪抑制成像(T1-weighted imaging fat-saturated,T1WI-FS)序列横轴位。沿关节软骨轮廓边缘勾画距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨作为感兴趣区(region of interest,ROI),获得相应的T2^(*)值。采用线性回归分析软骨T2^(*)值与年龄、BMI、跑龄的相关性,采用独立样本t检验分析不同跑量及不同性别间的软骨T2^(*)值差异。结果(1)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面及距骨面软骨T2^(*)值在性别上的差异均具有统计学意义(P=0.001、P<0.001、P=0.002、P=0.008、P=0.004);(2)高跑量组的距骨穹窿、后距下关节跟骨面软骨T2^(*)值高于中低跑量组(P=0.014、0.023),不同跑量的跟骰关节跟骨面及骰骨面、后距下关节距骨面软骨T2^(*)值的差异均无统计学意义(P=0.987、0.072、0.724);(3)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面、距骨面软骨T2^(*)值均与BMI呈正相关(r=0.376、0.384、0.300、0.422、0.455,P=0.005、0.004、0.019、0.001、0.001)。结论在业余马拉松运动员这一跑步群体中,与中低跑量相比,高跑量更有可能导致距骨穹窿、后距下关节跟骨面软骨损伤;而与较低的BMI相比,高BMI增加了距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨损伤的风险。 展开更多
关键词 业余马拉松 跑步 软骨 磁共振成像 T2^(*)mapping
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磁共振T2mapping技术在布氏杆菌性脊柱炎诊断中的应用
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作者 张小娟 胡娜 +2 位作者 李宇璞 赵鹏飞 乔鹏飞 《中国CT和MRI杂志》 2025年第4期172-175,共4页
目的研究旨在探讨磁共振T2mapping技术在布氏杆菌性脊柱炎定量诊断中的应用价值。方法对病例组42例布氏杆菌脊柱炎患者及对照组43例健康志愿者行腰椎常规MRI+T2mapping检查,测量病例组患者病变椎体、病变邻近正常椎体及对照组健康椎体的... 目的研究旨在探讨磁共振T2mapping技术在布氏杆菌性脊柱炎定量诊断中的应用价值。方法对病例组42例布氏杆菌脊柱炎患者及对照组43例健康志愿者行腰椎常规MRI+T2mapping检查,测量病例组患者病变椎体、病变邻近正常椎体及对照组健康椎体的T2mapping值,并进行统计分析。结果病例组42例患者中,男性中老年多见;病变以L4-L5椎体受累及侵犯相邻2个椎体多见;病变椎体附近软组织水肿发生率较高,约78.57%;椎旁脓肿发生率较低约27.27%;邻近硬膜囊受到压迫、椎管有效矢状径变窄约16.67%。病例组病变椎体的T2mapping值较病变邻近正常椎体及对照组健康椎体T2mapping值明显增高且差异有统计学意义(P<0.05)。病例组病变邻近正常椎体与对照组健康椎体T2mapping值相比较,差异无统计学意义(P>0.05)。结论T2mapping技术可以量化分析布氏杆菌性脊柱炎患者椎体的情况,对布氏杆菌性脊柱炎的诊断有重要参考价值。 展开更多
关键词 T2mapping 定量 布氏杆菌病 腰椎 脊柱炎
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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作者 Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests Database mapping Google Scholar HYPERLINKS DISPARITIES Unevenness
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T2 mapping不同测量方法在甲状腺相关眼病活动性评估中的应用
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作者 信雨晴 潘富强 +2 位作者 王亚磊 袁玉山 张杨 《中国CT和MRI杂志》 2025年第2期71-73,共3页
目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最... 目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最重眼肌的信号较高区域勾画小的ROI,记为热点)、T2SS(单只眼肌热点层面的均值)及T2SO(单侧眼眶四条眼肌肌腹层面的均值),分析三者与CAS的相关性及其诊断效能。结果活动期T2HS、T2SS和T2SO均高于非活动期。三者均与CAS正相关,T2SO相关性最强(r=0.606,P<0.0001)。ROC曲线显示三者对TAO活动性分期均有一定的诊断效能,虽然结果显示T2SS诊断效能较优,AUC=0.833,截断值94.25ms时判断活动性敏感度为68%,特异度为91%,但Delong检验提示三者差异无统计学意义。结论T2 mapping序列的三种测量方法均可用于TAO的活动性评估,综合分析,T2SS较适合用于分期。 展开更多
关键词 GRAVES眼病 T2 mapping 磁共振成像 感兴趣区 活动性分期 动眼肌
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磁共振联合T2-mapping对电针治疗腰椎间盘突出症中短期疗效评价的价值分析
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作者 朱薇萍 吕莹 +2 位作者 徐婷 戴德纯 屠建春 《上海针灸杂志》 2025年第3期290-295,共6页
目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LD... 目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LDH患者各32例,分别设为A组和B组。两组治疗前后分别记录腰椎日本骨科协会(Japanese Orthopaedic Association,JOA)评估治疗分数、Oswestry功能障碍指数(Oswestry disability index,ODI)评分,进行腰椎MR扫描并测量突出椎间盘髓核T2值和突出部分面积。两组均对治疗后JOA改善率及治疗前T2值、突出面积进行相关性分析,并比较治疗后及随访时T2值和突出面积。结果A组治疗前、治疗后及随访时突出椎间盘髓核T2值均明显高于B组(P<0.05);A组治疗1个疗程后突出部分面积明显小于B组(P<0.05)。A组治疗后JOA评分改善率与治疗前突出椎间盘髓核T2值具有中度相关关系(P<0.05),与突出部分面积未见有线性相关关系(P>0.05)。结论通过MR常规序列联合T2-mapping观察突出椎间盘髓核T2值,在电针治疗LDH中短期疗效评价中存在一定的临床价值,其或可为成为LDH保守治疗方案选择的辅助指标之一。 展开更多
关键词 针刺疗法 腰椎间盘突出症 电针 T2-mapping T2值
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A general methodological framework for hazard assessment in remote mountain areas combining geomorphological mapping with UAV survey
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作者 Elena GAROVA Bogdan CHADROMTSEV +6 位作者 Alexander PEDANOV Pavel GREBENNIKOV Igor ILTUGANOV Pavel LOBANOV Pavel PONOMARJOVS Felix DRAESNER Sven FUCHS 《Journal of Mountain Science》 2025年第3期763-775,共13页
This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing... This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing techniques and is adaptable to different national standards,thus ensuring its applicability in a variety of contexts.The principal objective is to guarantee the safety of mountainous regions,particularly in the vicinity of essential infrastructure,where the scope for implementing structural measures is restricted.The framework commences with comprehensive geomorphological mapping,which facilitates the identification of past hazardous processes and potential future hazards.New technologies,such as uncrewed aerial vehicles(UAVs),are employed to create high-resolution DEMs,which are particularly beneficial in regions with limited data availability.These models facilitate the assessment of potential hazards and inform decisions regarding protective measures.The utilisation of UAVs enhances the accuracy and efficiency of data collection,particularly in remote mountainous regions where alternative remotely sensed information may be unavailable.The integration of modern approaches into traditional hazard assessment methods allows for a comprehensive analysis of the spatial distribution of factors driving mass wasting processes.This workflow provides valuable insights that assist in the prioritisation of interventions and the optimisation of risk reduction in high mountainous areas. 展开更多
关键词 Geomorphological mapping Hazard assessment UAV Remote mountain areas Mitigation planning
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Effects of Rehabilitation Nursing Combined with Psychological Intervention Based on Mind Mapping Model on Emotional State and Treatment Compliance of Patients with Nephrotic Syndrome
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作者 Xiuju Huang Juan Zhang 《Journal of Clinical and Nursing Research》 2025年第3期64-69,共6页
Objective:To evaluate the value of rehabilitation nursing based on mind mapping model combined with psychological intervention for patients with nephrotic syndrome(NS).Methods:A total of 60 patients with NS who visite... Objective:To evaluate the value of rehabilitation nursing based on mind mapping model combined with psychological intervention for patients with nephrotic syndrome(NS).Methods:A total of 60 patients with NS who visited our hospital from January 2024 to December 2024 were selected as samples and randomly divided into groups.The observation group received rehabilitation nursing based on the mind mapping model combined with psychological intervention,while the control group received routine intervention.The differences in emotional scores,self-care ability scores,compliance,and complications were compared between the two groups.Results:The anxiety(SAS)and depression(SDS)scores of the observation group were lower than those of the control group,while the self-care ability scale(ESCA)score was higher than that of the control group(P<0.05).The compliance rate of the observation group was higher than that of the control group(P<0.05).The complication rate of NS in the observation group was lower than that in the control group(P<0.05).Conclusion:Rehabilitation nursing based on the mind mapping model combined with psychological intervention can enhance self-care ability,reduce negative emotions,and reduce complications in NS nursing,which is efficient and feasible. 展开更多
关键词 Nephrotic syndrome Psychological intervention Mind mapping model Rehabilitation nursing
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联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病肾功能的价值
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作者 李雪松 张庆娟 +2 位作者 余玉盛 周清清 张宏 《医学影像学杂志》 2025年第2期84-87,99,共5页
目的探讨联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病(CKD)肾功能的可行性。方法选取CKD患者81例,所有患者均行T_(2)WI、T_(1)-Mapping及T_(2)-Mapping扫描及肾功能生化检查。基于估算肾小球滤过率(eGFR)将患者分为轻、中及重度三组... 目的探讨联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病(CKD)肾功能的可行性。方法选取CKD患者81例,所有患者均行T_(2)WI、T_(1)-Mapping及T_(2)-Mapping扫描及肾功能生化检查。基于估算肾小球滤过率(eGFR)将患者分为轻、中及重度三组,测量肾脏T_(1)及T_(2)值并比较其组间差异及与eGFR的相关性。结果三组间肾皮质、髓质T_(1)值及髓质T_(2)值差异有统计学意义(F=8.353,9.431,10.090;P<0.05)。肾皮质T_(1)值、髓质T_(1)值及髓质T_(2)与eGFR存在相关性(r=-0.409,-0.389,0.372;P<0.05)。联合肾皮质、髓质T_(1)值及髓质T_(2)值在鉴别轻度与中、重度CKD的诊断效能最佳(AUC=0.869,P<0.001)。结论T_(1)-Mapping与T_(2)-Mapping对CKD肾功能评估具有一定参考价值;联合T_(1)-Mapping与T_(2)-Mapping可提高鉴别轻度与中、重度CKD的诊断效能。 展开更多
关键词 慢性肾病 肾功能评估 磁共振成像 定量技术
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GPU-Enabled Isogometric Topology Optimization with Bezier Element Stiffness Mapping
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作者 Xuesong Li Shuting Wang +3 位作者 Nianmeng Luo Aodi Yang Xing Yuan Xianda Xie 《Computer Modeling in Engineering & Sciences》 2025年第2期1481-1514,共34页
Due to the high-order B-spline basis functions utilized in isogeometric analysis(IGA)and the repeatedly updating global stiffness matrix of topology optimization,Isogeometric topology optimization(ITO)intrinsically su... Due to the high-order B-spline basis functions utilized in isogeometric analysis(IGA)and the repeatedly updating global stiffness matrix of topology optimization,Isogeometric topology optimization(ITO)intrinsically suffers from the computationally demanding process.In this work,we address the efficiency problem existing in the assembling stiffness matrix and sensitivity analysis using B˙ezier element stiffness mapping.The Element-wise and Interaction-wise parallel computing frameworks for updating the global stiffness matrix are proposed for ITO with B˙ezier element stiffness mapping,which differs from these ones with the traditional Gaussian integrals utilized.Since the explicit stiffness computation formula derived from B˙ezier element stiffness mapping possesses a typical parallel structure,the presented GPU-enabled ITO method can greatly accelerate the computation speed while maintaining its high memory efficiency unaltered.Numerical examples demonstrate threefold speedup:1)the assembling stiffness matrix is accelerated by 10×maximumly with the proposed GPU strategy;2)the solution efficiency of a sparse linear system is enhanced by up to 30×with Eigen replaced by AMGCL;3)the efficiency of sensitivity analysis is promoted by 100×with GPU applied.Therefore,the proposed method is a promising way to enhance the numerical efficiency of ITO for both single-patch and multiple-patch design problems. 展开更多
关键词 Isogeometric analysis topology optimization GPU sparse system solver Bezier element stiffness mapping
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Assessment of plant diversity in the Surkhan-Sherabad Region,Uzbekistan by grid mapping
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作者 Inom JURAMURODOV Rustam URALOV +6 位作者 Dilmurod MAKHMUDJANOV LU Chunfang Feruz AKBAROV Sardor PULATOV Bakhtiyor KARIMOV Orzimat TURGINOV Komiljon TOJIBAEV 《Journal of Arid Land》 2025年第3期394-410,共17页
In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a th... In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups. 展开更多
关键词 grid mapping species richness collection density TAXONOMY dominant species life form therophyte Central Asia
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Power forecasting method of ultra-short-term wind power cluster based on the convergence cross mapping algorithm
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作者 Yuzhe Yang Weiye Song +5 位作者 Shuang Han Jie Yan Han Wang Qiangsheng Dai Xuesong Huo Yongqian Liu 《Global Energy Interconnection》 2025年第1期28-42,共15页
The development of wind power clusters has scaled in terms of both scale and coverage,and the impact of weather fluctuations on cluster output changes has become increasingly complex.Accurately identifying the forward... The development of wind power clusters has scaled in terms of both scale and coverage,and the impact of weather fluctuations on cluster output changes has become increasingly complex.Accurately identifying the forward-looking information of key wind farms in a cluster under different weather conditions is an effective method to improve the accuracy of ultrashort-term cluster power forecasting.To this end,this paper proposes a refined modeling method for ultrashort-term wind power cluster forecasting based on a convergent cross-mapping algorithm.From the perspective of causality,key meteorological forecasting factors under different cluster power fluctuation processes were screened,and refined training modeling was performed for different fluctuation processes.First,a wind process description index system and classification model at the wind power cluster level are established to realize the classification of typical fluctuation processes.A meteorological-cluster power causal relationship evaluation model based on the convergent cross-mapping algorithm is pro-posed to screen meteorological forecasting factors under multiple types of typical fluctuation processes.Finally,a refined modeling meth-od for a variety of different typical fluctuation processes is proposed,and the strong causal meteorological forecasting factors of each scenario are used as inputs to realize high-precision modeling and forecasting of ultra-short-term wind cluster power.An example anal-ysis shows that the short-term wind power cluster power forecasting accuracy of the proposed method can reach 88.55%,which is 1.57-7.32%higher than that of traditional methods. 展开更多
关键词 Ultra-short-term wind power forecasting Wind power cluster Causality analysis Convergence cross mapping algorithm
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Doline susceptibility mapping using multisource data in the karst aquifers of Saldaran mountain,High Zagros Belt
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作者 Peyman MOHAMMADI-AHMADMAHMOUDI Somaiyeh KHALEGHI Mohsen EHTESHAMI-MOINABADI 《Journal of Mountain Science》 2025年第2期422-435,共14页
Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of ... Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of dolines.In this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology map.Only 8 parameters have been inputted to the model which had correlation with dolines.In this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for modelling.The results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate class.Also,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab aquifers.Also,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,respectively.Accurate evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model. 展开更多
关键词 Doline susceptibility mapping UAV photogrammetry Karst aquifers Generalized linear model(GLM) High Zagros Belt
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DTI联合T2 mapping在神经根型颈椎病神经根损伤定量评价中的应用
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作者 赵锐荣 张凤翔 张芳 《影像技术》 2025年第1期50-56,67,共8页
目的:探讨弥散张量成像(DTI)联合T2 mapping技术在定量评价神经根型颈椎病患者神经根损伤中的应用价值。方法:对82例神经根型颈椎病患者与30例健康志愿者进行颈椎间盘常规MRI、DTI、T2 mapping及T1 Vibe检查。测量所有受试者神经根的各... 目的:探讨弥散张量成像(DTI)联合T2 mapping技术在定量评价神经根型颈椎病患者神经根损伤中的应用价值。方法:对82例神经根型颈椎病患者与30例健康志愿者进行颈椎间盘常规MRI、DTI、T2 mapping及T1 Vibe检查。测量所有受试者神经根的各序列参数,包括FA(各向异性分数)、ADC(表观扩散系数)、AD(轴向扩散系数)、RD(径向扩散系数)及T2值。利用VAS评分对患者进行疼痛学评分。比较患者受压神经根与健康志愿者神经根的各序列参数值差异,并分析各序列参数值与VAS评分的相关性。结果:神经根型颈椎病患者的患侧神经根较健侧及健康志愿者神经根FA值显著减低,ADC、AD、RD、T2值显著升高(P<0.05)。患侧神经根FA平均值与VAS评分呈中度负相关(r=-0.544),ADC、AD、RD、T2平均值与VAS呈正相关(ADC:r=0.457;AD:0.249;RD:0.390;T2:r=0.497)(P<0.05)。ROC曲线分析显示,当DTI所有参数与T2值联合时,曲线下面积(AUC)最大,为0.980,对应的敏感度为95.3%,特异度为94.6%。结论:DTI及T2 mapping技术可以用于评价神经根型颈椎病患者颈神经根损伤,且当DTI与T2 mapping联合使用时可获得最佳诊断效能。 展开更多
关键词 磁共振成像 弥散张量成像 T2图谱 定量分析 颈神经根
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磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值 被引量:1
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作者 唐毅 张辉 +1 位作者 黄恺 黎本丰 《中国CT和MRI杂志》 2024年第4期163-165,共3页
目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我... 目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我院进行体检的64例健康者为对照组,受试者均行磁共振T1rho序列、T2 mapping技术扫描,测量受试者T2值及T1ρ值,探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。结果观察组股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值均明显高于对照组(P<0.05),重度退变亚组患者股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值显著高于轻度退变者(P<0.05);观察组股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于对照组(P<0.05),重度退变亚组患者股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于轻度退变亚组患者(P<0.05);磁共振T1rho序列在膝关节早期软骨退变中早期诊断及严重程度评估中的的诊断ROC值及特异度明显高于T2 mapping技术(P<0.05),但后者具有更高的敏感度(P<0.05)。结论磁共振T1rho序列、T2 mapping技术均能有效反映膝关节早期软骨退变中软骨组织学成分变化情况,还可为膝关节软骨退变严重程度评估提供客观依据,二者具有一定互补价值。 展开更多
关键词 磁共振T1rho序列 T2 mapping技术 膝关节 早期软骨退变 诊断
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MR T2^(*)mapping成像技术定量评价腰椎小关节炎软骨损伤 被引量:2
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作者 陈吉 张晨 +1 位作者 张濒 黄磊涛 《中国组织工程研究》 CAS 北大核心 2024年第30期4866-4870,共5页
背景:腰椎小关节炎是引起下腰痛的一个主要原因,目前主要依靠MRI进行初步定性诊断,但仍有一定漏诊、误诊的概率发生,因此MR T2^(*)mapping成像技术有望成为定量检查腰椎小关节炎软骨损伤的重要检测手段。目的:探讨MR T2^(*)mapping成像... 背景:腰椎小关节炎是引起下腰痛的一个主要原因,目前主要依靠MRI进行初步定性诊断,但仍有一定漏诊、误诊的概率发生,因此MR T2^(*)mapping成像技术有望成为定量检查腰椎小关节炎软骨损伤的重要检测手段。目的:探讨MR T2^(*)mapping成像技术在定量分析腰椎小关节炎软骨损伤退变中的应用价值。方法:收集南京医科大学第四附属医院2020年4月至2022年3月门诊或住院合并下腰痛共110例患者,设为病例组;同时招募无症状志愿者80例,设为对照组。对所有纳入对象L1-S1的小关节行3.0 T MR扫描,获取T2^(*)mapping横断位图像和T2WI图像,分别对所有小关节软骨进行Weishaupt分级及T2^(*)值测量,收集数据并行统计学分析。不同小关节Weishaupt分级之间小关节软骨T2^(*)值比较采用单因素方差分析。结果与结论:①经统计分析发现,病例组腰椎小关节软骨T2^(*)值(17.6±1.5)ms明显较对照组(21.4±1.3)ms降低,差异有显著性意义(P<0.05);②在病例组中,随着腰椎小关节Weishaupt分级增加,小关节软骨T2^(*)值也呈逐渐下降趋势,且这种差异有显著性意义(P<0.05);③提示T2^(*)mapping能够较好地显示腰椎小关节软骨损伤的早期病理变化,腰椎小关节软骨的T2^(*)值能够定量评估腰椎小关节的软骨损伤程度;T2^(*)mapping成像技术能为影像学诊断腰椎小关节炎软骨早期损伤提供很好的理论依据,具有重要的临床应用价值。 展开更多
关键词 腰椎小关节炎 T2^(*)mapping T2^(*)值 小关节软骨退变 下腰痛
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