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Effect of land use on soil nematode community composition and co-occurrence network relationship
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作者 Xiaotong Liu Siwei Liang +3 位作者 Yijia Tian Xiao Wang Wenju Liang Xiaoke Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2807-2819,共13页
Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,for... Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern China.Generic richness,diversity,abundance and biomass of soil nematodes was the lowest in crop land.The richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,respectively.No significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was different.Among the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were bacterivores.The proportion of fungivores in forest land was 20.8%lower than in fallow land.The network complexity and the stability were lower in crop land than forest land and fallow land.Soil pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest land.Soil nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow land.Land use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera. 展开更多
关键词 soil nematode trophic groups community composition co-occurrence network land use
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Machine learning prediction model for gray-level co-occurrence matrix features of synchronous liver metastasis in colorectal cancer
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作者 Kai-Feng Yang Sheng-Jie Li +1 位作者 Jun Xu Yong-Bin Zheng 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1571-1581,共11页
BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the ... BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the diagnosis of CRC.AIM To explore the risk factors for SLM in CRC and construct a visual prediction model based on gray-level co-occurrence matrix(GLCM)features collected from magnetic resonance imaging(MRI).METHODS Our study retrospectively enrolled 392 patients with CRC from Yichang Central People’s Hospital from January 2015 to May 2023.Patients were randomly divided into a training and validation group(3:7).The clinical parameters and GLCM features extracted from MRI were included as candidate variables.The prediction model was constructed using a generalized linear regression model,random forest model(RFM),and artificial neural network model.Receiver operating characteristic curves and decision curves were used to evaluate the prediction model.RESULTS Among the 392 patients,48 had SLM(12.24%).We obtained fourteen GLCM imaging data for variable screening of SLM prediction models.Inverse difference,mean sum,sum entropy,sum variance,sum of squares,energy,and difference variance were listed as candidate variables,and the prediction efficiency(area under the curve)of the subsequent RFM in the training set and internal validation set was 0.917[95%confidence interval(95%CI):0.866-0.968]and 0.09(95%CI:0.858-0.960),respectively.CONCLUSION A predictive model combining GLCM image features with machine learning can predict SLM in CRC.This model can assist clinicians in making timely and personalized clinical decisions. 展开更多
关键词 Colorectal cancer Synchronous liver metastasis Gray-level co-occurrence matrix Machine learning algorithm Prediction model
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Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia 被引量:1
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作者 Prayitno Abadi Ihsan N.Muafiry +8 位作者 Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi 《Earth and Planetary Physics》 EI CAS 2025年第1期101-116,共16页
This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signa... This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research. 展开更多
关键词 Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map
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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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基于MAP法的线路板重金属铜氨废水处理研究
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作者 黄常亮 《现代工程科技》 2025年第1期77-80,共4页
随着线路板的广泛应用,其在印刷过程中产生的铜氨废水的排放问题日益突出。铜氨废水中氨氮和铜离子对环境的危害较大,为了解决该问题,提出了一种MAP法和折点氯化法相结合的方法。该方法首先向铜氨废水中加入镁盐和磷酸盐,将氨氮转化为MA... 随着线路板的广泛应用,其在印刷过程中产生的铜氨废水的排放问题日益突出。铜氨废水中氨氮和铜离子对环境的危害较大,为了解决该问题,提出了一种MAP法和折点氯化法相结合的方法。该方法首先向铜氨废水中加入镁盐和磷酸盐,将氨氮转化为MAP沉淀,降低铜氨废水中氨氮的浓度,同时可以将MAP回收再利用;然后向剩余浓液中加入过量的NaClO溶液,进一步将溶液中的氨氮浓度降低,随着NaClO溶液的增加,反应液会逐渐呈碱性,而Cu^(2+)在碱性环境中会与OH-生成Cu(OH)_(2)沉淀,进而降低Cu^(2+)的浓度,从而使铜氨废水中的氨氮和Cu2+的浓度均符合《中华人民共和国环境保护法》的排放要求;最后通过纳氏试剂分光光度法和火焰原子吸收光度法检验反应后浓液中氨氮和Cu^(2+)的浓度。经过验证得知,该方法可以显著降低氨氮和Cu^(2+)的浓度。 展开更多
关键词 map 铜氨废水 氨氮回收 线路板 折点氯化法 环保排放标准
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Compiling molecular evidence from a tetraploid rose genome into a near-saturated map for the identification of pigment-related genes
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作者 Bixuan Cheng Yanlin Sun +6 位作者 Huihua Wan Kai Zhao Lidan Sun Le Luo Huitang Pan Qixiang Zhang Chao Yu 《Horticultural Plant Journal》 2025年第1期351-366,共16页
With their high economic value and cultural significance,modern roses are one of the most important ornamental plants.Because of their complicated genetic background and tetraploid nature,the creation of high-density ... With their high economic value and cultural significance,modern roses are one of the most important ornamental plants.Because of their complicated genetic background and tetraploid nature,the creation of high-density genetic maps of roses has been a challenge that has slowed the pace of molecular breeding for modern roses.The current construction of tetraploid genetic maps based on existing diploid rose genomes could lead to inaccurate marker information and genotyping results.Therefore,we generated the first high-quality tetraploid genome of Rosa chinensis‘Yunzheng Xiawei.'Utilizing Illumina,PacBio,and Hi-C sequencing technologies,we assembled a genome of 858.59 Mb with 14pseudo-chromosomes.Mode of inheritance analysis using PolyOrigin indicated that modern roses show both quadrivalent and bivalent pairing.Based on this reference genome,high-density genetic maps were constructed using MSTmap with nearly saturated markers.Quantitative trait locus(QTL)analysis was conducted using WinQTLCart and R/qtl for flavonoids and carotenoids,and 11 QTL clusters were identified.By combining the genome annotation,phylogenetic analyses,and gene expression analyses,we were able to identify several key genes related to flavonoid and carotenoid biosynthesis.This study provides the basis for further genetic analyses of highly heterozygous tetraploid roses and could facilitate the progress of marker-assisted selection in modern roses. 展开更多
关键词 ROSA Tetraploid genome Tetrasomic inheritance Genetic linkage map Flower color
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Identification of long InDels through whole genome resequencing to fine map qIF05-1 for seed isoflavone content in soybean(Glycine max L. Merr.)
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作者 Jia Jia Huan Wang +5 位作者 Ximeng Yang Bo Chen Ruqian Wei Qibin Ma Yanbo Cheng Hai Nian 《Journal of Integrative Agriculture》 2025年第1期85-100,共16页
Soybean seed isoflavones are a type of secondary metabolites that can provide health and nutrition benefits for humans. In our previous study, a stable quantitative trait locus(QTL) qIF05-1 controlling the seed isofla... Soybean seed isoflavones are a type of secondary metabolites that can provide health and nutrition benefits for humans. In our previous study, a stable quantitative trait locus(QTL) qIF05-1 controlling the seed isoflavone content in soybean was detected on chromosome(Chr.) 05 in a recombinant inbred line(RIL) population from a cross of Huachun 2×Wayao. In this study, the parental lines were re-sequenced using the Illumina Solexa System with deep coverage. A total of 63,099 polymorphic long insertions and deletions(InDels)(≥15 bp)were identified between the parents Huachun 2 and Wayao. The InDels were unevenly distributed on 20chromosomes of soybean, varying from 1,826 in Chr. 12 to 4,544 in Chr. 18. A total of 10,002 long InDels(15.85% of total) were located in genic regions, including 1,139 large-effect long InDels which resulted in truncated or elongated protein sequences. In the qIF05-1 region, 68 long InDels were detected between the two parents. Using a progeny recombination experiment and genotype analysis, the qIF05-1 locus was mapped into a 102.2 kb genomic region, and this region contained 12 genes. By RNA-seq data analysis, genome sequence comparison and functional validation through ectopic expression in Arabidopsis thaliana, Glyma.05G208300(described as GmEGL3), which is a basic helix-loop-helix(bHLH) transcription factor in plants, emerged as the most likely confirmed gene in qIF05-1. These long InDels can be used as a type of complementary genetic method for QTL fine mapping, and they can facilitate genetic studies and molecular-assisted selection breeding in soybean. 展开更多
关键词 SOYBEAN seed isoflavone content whole genome re-sequencing long InDels fine map
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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 B˙ezier element stiffness mapping
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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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基于co-occurrence相似度的聚类集成方法 被引量:3
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作者 凌光 王明春 冯嘉毅 《计算机应用》 CSCD 北大核心 2011年第2期441-445,461,共6页
首先提出了一种基于属性值的co-occurrence相似度概念,通过对其进一步的研究,提出了3个等价性表述;然后对属性值之间的co-occurrence相似度进行引申,给出了数据对象之间co-occurrence相似度的定义,并将其成功应用到聚类集成方法中。利用... 首先提出了一种基于属性值的co-occurrence相似度概念,通过对其进一步的研究,提出了3个等价性表述;然后对属性值之间的co-occurrence相似度进行引申,给出了数据对象之间co-occurrence相似度的定义,并将其成功应用到聚类集成方法中。利用co-occurrence相似度在计算某个初始聚类结果中数据对象之间的相似度时,充分考虑了其他初始聚类结果和该初始聚类结果之间的相互影响和联系。实验表明,基于co-occurrence相似度的聚类集成(CSCE)方法能有效识别数据之间的细微结构,有助于提高聚类集成的效果。 展开更多
关键词 聚类集成 binary相似度 co-occurrence相似度 基于簇相似的划分算法 基于co-occurrence相似度的聚类集成
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融合Mind Map优势助力完善线上线下教学衔接--以园林树木学树种识别教学为例 被引量:2
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作者 刘艺平 贺丹 +1 位作者 李永华 张曼 《高教学刊》 2024年第1期78-81,共4页
疫情当前,线上线下混合式教学已经成为课程教学新模式。树种识别是园林树木学教学的重点和难点,也是教学目的之一。由于课程涉及的树种种类繁多,知识点琐碎,专业术语抽象,再加上课时少任务重,使得教师在教学过程中无法将所有树种的特征... 疫情当前,线上线下混合式教学已经成为课程教学新模式。树种识别是园林树木学教学的重点和难点,也是教学目的之一。由于课程涉及的树种种类繁多,知识点琐碎,专业术语抽象,再加上课时少任务重,使得教师在教学过程中无法将所有树种的特征逐一讲解到,学生在学习过程中也容易混淆,无法有效吸收知识点。因此,在课程的教学改革中,通过引入Mind Map帮助厘清知识框架,优化知识结构,搭建知识关联,不仅使教师授课过程更顺畅,而且能够激发学生在线学习的兴趣,促使学生养成“整理知识点”的良好习惯,使学习效率大幅度提高,从而创建高效的线上课堂,有效巩固混合式教学的教学效果。 展开更多
关键词 线上线下 园林树木学 Mind map 树种识别 混合式教学
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基于加权co-occurrence矩阵的聚类集成算法
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作者 柏建普 杨亚坤 《电子科技》 2012年第2期19-22,共4页
聚类集成是数据挖掘研究的一个热点。它是利用同一数据集的多个聚类划分集成在一起,以提高聚类分析的性能。当前相关研究大多没有考虑进行集成的聚类成员的质量,因此较差的成员会对集成结果产生不良影响。文中提出了一种基于加权co-occu... 聚类集成是数据挖掘研究的一个热点。它是利用同一数据集的多个聚类划分集成在一起,以提高聚类分析的性能。当前相关研究大多没有考虑进行集成的聚类成员的质量,因此较差的成员会对集成结果产生不良影响。文中提出了一种基于加权co-occurrence矩阵的聚类集成算法(WCSCE)。该方法首先计算出聚类成员基于属性值的co-occurrence矩阵,然后对聚类成员的质量进行简单评价并赋予权重,生成加权co-occurrence矩阵,进而产生集成结果。最后通过实验验证了该算法的有效性,并提高了聚类质量。 展开更多
关键词 聚类集成 co-occurrence矩阵 权重
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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:1
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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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MOLLI T1 mapping定量技术在儿童脑发育评估中的应用可行性探讨
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作者 杨雪 贾凤林 +6 位作者 马鑫茂 李学胜 李珮 张露 廖怡 宁刚 曲海波 《磁共振成像》 CAS CSCD 北大核心 2024年第11期32-38,共7页
目的探讨改良回顾反转恢复(modified Look-Locker inversion recover,MOLLI)序列T1 mapping定量技术在定量评价儿童脑部发育中的价值。材料与方法纳入头部磁共振检查正常的儿童53例,使用优化后的MOLLI及磁化准备2快速采集梯度回波(magne... 目的探讨改良回顾反转恢复(modified Look-Locker inversion recover,MOLLI)序列T1 mapping定量技术在定量评价儿童脑部发育中的价值。材料与方法纳入头部磁共振检查正常的儿童53例,使用优化后的MOLLI及磁化准备2快速采集梯度回波(magnetization prepared 2 rapid acquisition gradient echoes,MP2RAGE)序列对每例受检者的36个脑区进行T1 mapping定量分析。评价两个序列所得各脑区T1值的一致性,比较两个序列各脑区T1值的差异,分析两个序列各脑区T1值与年龄之间的相关性。结果MOLLI序列和MP2RAGE序列除在双侧脑桥背侧、大脑脚组内相关系数(intra-class correlation coefficient,ICC)<0.8(P<0.001)外,其余脑区ICC均>0.8(P<0.001)。两个序列各脑区的T1值差异均有统计学意义(P<0.05,FDR校正),MOLLI组各脑区T1值高于MP2RAGE组。两个序列各脑区的T1值均与年龄呈负相关(P均<0.001)。结论优化后的MOLLI序列可用于儿童脑部发育的定量评价,与MP2RAGE序列一致性好,可较准确地量化脑区的T1值,为儿童神经系统的研究提供了新的方法选择。 展开更多
关键词 脑发育 儿童 磁共振成像 改良回顾反转恢复序列 T1 mapping 髓鞘
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MAP添加液对冰冻解冻去甘油红细胞保存的质量影响
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作者 杨剑豪 聂晓绚 +5 位作者 张莉莉 章舜玮 杜祎 邱颖婕 马庆 徐蓓 《中国输血杂志》 CAS 2024年第6期684-689,共6页
目的观察冰冻解冻去甘油红细胞悬浮于MAP添加液中对保存效果的影响,探索最佳保存方式。方法本研究将采集后d 3的400 mL全血,离心制备成浓缩红细胞,使用ACP 215全自动血细胞仪,加入40%复方甘油溶液,置于-65℃超低温冰箱中保存30 d,解冻... 目的观察冰冻解冻去甘油红细胞悬浮于MAP添加液中对保存效果的影响,探索最佳保存方式。方法本研究将采集后d 3的400 mL全血,离心制备成浓缩红细胞,使用ACP 215全自动血细胞仪,加入40%复方甘油溶液,置于-65℃超低温冰箱中保存30 d,解冻去甘油洗涤后,等量分离成两袋,以添加0.9%氯化钠溶液为对照组;添加MAP为实验组,两组保存于2~6℃冷藏条件下,分别于0、1、3、5、7、14 d取样检测血液学参数指标、溶血指标、细胞代谢指标,观察两组在14 d保存期内的质量变化情况。结果研究发现两组红细胞在解冻去甘油后6项质控项目包括容量、血红蛋白含量、游离血红蛋白含量、白细胞残留量、甘油残留量、无菌试验的检测值均符合《全血及成分血质量要求》(GB18469-2012);压积、红细胞计数、Hb洗涤后回收率、MCV符合《冰冻红细胞质量评价指标专家共识》检测限值,血小板残留量超过检测限值(≤1%);在14 d保存期内,两组的RBC、Hct、MCV和血红蛋白含量值无统计学意义;两组游离血红蛋白、溶血率和K+值随保存时间延长而增加,分别于3、5、7、14 d;3、5、7、14 d;14 d组间有统计学意义(P<0.05),两组红细胞渗透脆性于14 d组间有统计学意义(P<0.05);两组ATP、pH值随保存时间延长而下降,分别于3、5、7 d;1、3、5、7、14 d组间有统计学意义(P<0.05)。结论悬浮于MAP添加液中的冰冻解冻去甘油红细胞可将血液保存期延长至7 d,本研究为相关标准的制定提供参考依据。 展开更多
关键词 冰冻解冻去甘油红细胞 map ACP215 保存期 血液质量控制
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番鸭VIPR1和miR-317以及MAP3K7和miR-244靶向关系的研究
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作者 李丽 辛清武 +4 位作者 章琳俐 缪中纬 朱志明 梁阿政 郑嫩珠 《中国家禽》 北大核心 2024年第6期15-19,共5页
试验旨在验证番鸭就巢相关miRNA与靶基因靶向关系。试验利用miRanda、PITA和RNAhybrid三个软件的交集预测miR-317和miR-244靶基因,构建VIPR1-pmirGLO/MAP3K7-pmirGLO野生型和突变型双荧光素酶重组载体,将miR-317/VIPR1-Wt和miR-244/MAP3... 试验旨在验证番鸭就巢相关miRNA与靶基因靶向关系。试验利用miRanda、PITA和RNAhybrid三个软件的交集预测miR-317和miR-244靶基因,构建VIPR1-pmirGLO/MAP3K7-pmirGLO野生型和突变型双荧光素酶重组载体,将miR-317/VIPR1-Wt和miR-244/MAP3K7-Wt分别共转染至鸭胚成纤维细胞,检测双荧光素酶活性。结果显示:与miR-NC组相比,miR-317/VIPR1-Wt共转染组相对荧光值显著降低(P<0.05);VIPR1突变后,miR-NC组与miR-317组的相对荧光值不显著(P>0.05),说明突变后完全抑制miR-317对VIPR1的结合作用,VIPR1与miR-317之间存在相互结合作用。与miR-NC组相比,miR-244/MAP3K7-Wt共转染组相对荧光值无显著性差异(P>0.05);MAP3K7突变后,miR-NC组与miR-244组的相对荧光值差异不显著(P>0.05),表明MAP3K7与miR-244之间不存在相互结合作用。研究提示,miR-317与VIPR1存在确切靶向结合位点,即VIPR1是miRNA miR-317的靶基因,而miR-244与MAP3K7不存在靶向关系。 展开更多
关键词 番鸭 就巢 miR-317 miR-244 map3K7 VIPR1
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T2 mapping定量分析在慢性踝关节不稳患者术前与术后远期随访中的应用
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作者 尤云峰 韩晓兵 +4 位作者 程鸿琦 林雅萍 康晓强 彭伟生 黄莹 《分子影像学杂志》 2024年第12期1367-1371,共5页
目的探讨T2 mapping定量分析评估慢性踝关节不稳患者术前与术后远期关节软骨退变情况。方法选取2021年1月~2022年6月我院收治的60例进行距腓前韧带(ATFL)修复或重建治疗的慢性踝关节不稳患者为研究对象,根据治疗方法将其分为ATFL修复组(... 目的探讨T2 mapping定量分析评估慢性踝关节不稳患者术前与术后远期关节软骨退变情况。方法选取2021年1月~2022年6月我院收治的60例进行距腓前韧带(ATFL)修复或重建治疗的慢性踝关节不稳患者为研究对象,根据治疗方法将其分为ATFL修复组(n=30)和ATFL重建组(n=30),另选择30例健康受试者作为对照组,ATFL修复组、ATFL重建组于术前和术后1年均进行MRI T2 mapping扫描和踝关节跖屈、背伸活动度以及疼痛视觉模拟评分(VAS)、美国足踝外科踝-后足功能系统(AOFAS)、踝关节Karlsson评分(KAFS)评估,对照组进行MRI T2 mapping扫描,测量和计算3组距骨顶前内侧、外侧和中央内侧、外侧以及后内侧、外侧软骨区域T2值。结果ATFL修复组术前距骨顶中央内侧及前内侧、外侧软骨区域T2值均高于对照组(P<0.05);ATFL修复组术后1年距骨顶中央内侧、外侧及前内侧、外侧软骨区域T2值均高于对照组(P<0.05);ATFL修复组术后1年距骨顶中央内侧及前内侧、外侧软骨区域T2值均高于术前(P<0.05)。ATFL重建组术前距骨顶中央内侧、外侧及前内侧、外侧软骨区域T2值均高于对照组(P<0.05);ATFL重建组术后1年距骨顶中央内侧、外侧及前内侧、外侧软骨区域T2值均高于对照组(P<0.05);ATFL重建组术后1年距骨顶中央外侧及前外侧软骨区域T2值均高于术前(P<0.05)。ATFL修复组与ATFL重建组术前、术后1年各软骨区域T2值比较差异均无统计学意义(P>0.05)。术后1年,ATFL修复组、ATFL重建组踝关节跖屈、背伸活动度均大于术前(P<0.05),VAS评分均低于术前(P<0.05),AOFAS、KAFS评分均高于术前(P<0.05)。结论慢性踝关节不稳患者在ATFL修复或重建治疗后仍会发生距骨软骨退变,主要是距骨顶前侧和中央,通过T2 mapping定量分析可评估慢性踝关节不稳患者术后距骨软骨退变情况。 展开更多
关键词 慢性踝关节不稳 磁共振成像 T2 mapping 随访
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传统武术套路训练对大学生武术运动员膝关节软骨影响的T2-mapping功能磁共振成像研究 被引量:3
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作者 邓成虎 王晨宇 +3 位作者 冉君 章瑶 李小明 夏薇 《影像科学与光化学》 CAS 2024年第3期219-225,共7页
目的:本研究旨在通过T2-mapping功能磁共振影像学技术对大学生武术运动员膝关节软骨进行定量评估,探究传统武术套路训练对大学生武术运动员膝关节软骨的影响。方法:选取9名年龄介于18~25岁之间的大学生武术运动员作为实验组,同时选取18... 目的:本研究旨在通过T2-mapping功能磁共振影像学技术对大学生武术运动员膝关节软骨进行定量评估,探究传统武术套路训练对大学生武术运动员膝关节软骨的影响。方法:选取9名年龄介于18~25岁之间的大学生武术运动员作为实验组,同时选取18名普通健康的大学生作为对照组。在相同条件下,对两组分别进行右膝关节的T2-mapping磁共振检查,并将膝关节软骨分为股骨内侧髁、胫骨内侧髁、髌软骨、股骨外侧髁及胫骨外侧髁5个感兴趣区,比较实验组与对照组之间T2值的差异,分析各组膝关节软骨不同感兴趣区T2值的变化。结果:(1)不论性别,实验组和对照组各个膝关节面软骨感兴趣区的T2值均未见显著性差异(P>0.05);(2)男性对照组、女性对照组以及女性实验组的膝关节各感兴趣区T2值两两之间均无统计学差异(P>0.05);(3)男性实验组膝关节股骨外侧髁与胫骨内侧髁、髌软骨的T2值差异具有统计学意义(P<0.05)。结论:T2-mapping技术可通过无创手段定量评估传统武术套路训练对大学生膝关节软骨的影响。在长期传统武术套路训练后,男性大学生武术运动员的膝关节出现了异质性改变,因此在训练过程中应该注意调整方案,以实现针对性保护。 展开更多
关键词 传统武术套路 大学生 膝关节 软骨 T2-mapping 磁共振成像
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DWI联合T2 mapping序列鉴别前列腺癌与前列腺增生价值评估 被引量:2
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作者 李茜玮 陈丽华 +2 位作者 王楠 林良杰 刘爱连 《磁共振成像》 CAS CSCD 北大核心 2024年第2期97-102,共6页
目的探讨扩散加权成像(diffusion-weighted imaging,DWI)联合T2 mapping序列鉴别前列腺癌(prostate cancer,PCa)与前列腺增生(benign prostatic hyperplasia,BPH)的价值。材料与方法回顾性分析本院行3.0 T MRI检查且经病理证实的56例PC... 目的探讨扩散加权成像(diffusion-weighted imaging,DWI)联合T2 mapping序列鉴别前列腺癌(prostate cancer,PCa)与前列腺增生(benign prostatic hyperplasia,BPH)的价值。材料与方法回顾性分析本院行3.0 T MRI检查且经病理证实的56例PCa患者及40例BPH患者资料。扫描序列包括T1WI、T2WI、DWI及T2 mapping序列。两名观察者分别测量两组病灶的表观扩散系数(apparent diffusion coefficient,ADC)值及T2值。采用组内相关系数(intra-class correlation coefficient,ICC)评估两名观察者测得参数值的一致性。采用独立样本t检验或Mann-Whitney U检验分析两组病例间ADC值及T2值的差异。Logistic回归用于分析差异具有统计学意义的参数及其与基线资料联合的诊断模型。采用受试者工作特征(receiver operating characteristic,ROC)曲线评估有差异参数及联合模型的诊断效能。采用DeLong检验比较ROC曲线下面积差异。采用Spearman相关系数分析ADC值与T2值相关性。结果两名观察者测量值一致性好(ICC>0.75)。PCa组的ADC值及T2值分别低于BPH组,差异具有统计学意义(P<0.01)。ADC值、T2值、ADC-T2及ADC-T2-年龄-总前列腺特异性抗原(total prostate specific antigen,TPSA)联合鉴别PCa与BPH的AUC值分别为0.843、0.830、0.896及0.927。DeLong检验显示ADC值与ADC-T2联合,ADC值、T2值、ADC-T2模型与ADC-T2-年龄-TPSA联合模型的ROC差异存在统计学意义(P<0.05)。ADC值与T2值呈正相关(r=0.331,P<0.01)。结论DWI及T2 mapping序列在鉴别PCa与BPH方面具有较好的价值,并且两序列联合临床指标时诊断效能提升,可为临床无创诊断PCa及BPH提供很好的指导意义。 展开更多
关键词 前列腺癌 前列腺增生 扩散加权成像 T2 mapping成像 磁共振成像 鉴别诊断
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