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中国阿尔茨海默病早期预防指南(2024) 被引量:1
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作者 林璐 马辛 +28 位作者 王刚 王虹峥 王志群 王志稳 王晓明 王惠芳 朱飞奇 乔立艳 刘肇瑞 齐志刚 汤彬 李坤成 李朝辉 肖世富 郁金泰 周显波 赵禾欣 赵忙所 赵红彬 顾耘 郭红 郭玲 郭起浩 富丽萍 雷敏 潘伟刚 徐勇 王军 阿尔茨海默病防治协会 《阿尔茨海默病及相关病杂志》 2024年第3期168-175,共8页
阿尔茨海默病是一种病因复杂的严重智力致残疾病,目前尚无有效的治疗方法。我国是世界上老年人口最多、增长最快的国家之一,也是阿尔茨海默病发病率较高的国家。因此,如何早期预防阿尔茨海默病的发生,是现今健康领域最重要的课题之一。... 阿尔茨海默病是一种病因复杂的严重智力致残疾病,目前尚无有效的治疗方法。我国是世界上老年人口最多、增长最快的国家之一,也是阿尔茨海默病发病率较高的国家。因此,如何早期预防阿尔茨海默病的发生,是现今健康领域最重要的课题之一。我们在国内外相关研究的基础上,通过文献循证、干预研究实践、案例分析、经验总结和专家咨询,结合中国老年健康和社会文化特点,体现中国传统医学、武术、养生以及社区组织优势,制订出具有中国特色的阿尔茨海默病早期预防指南,涵盖了个人、家庭和社会三个层面的预防策略,从积极生活态度、社会活动参与、认知训练、体育锻炼、戒烟限酒、营养、睡眠,血压、血糖、血脂管理,体重和其他慢病管理以及中医开展针对阿尔茨海默病的一级预防。本指南仅供个人、家庭和社会开展阿尔茨海默病预防时参考。 展开更多
关键词 阿尔茨海默病 早期预防 指南
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A deep convolutional neural network for diabetic retinopathy detection via mining local and long-range dependence 被引量:1
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作者 Xiaoling Luo Wei Wang +4 位作者 yong xu Zhihui Lai Xiaopeng Jin Bob Zhang David Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期153-166,共14页
Diabetic retinopathy(DR),the main cause of irreversible blindness,is one of the most common complications of diabetes.At present,deep convolutional neural networks have achieved promising performance in automatic DR d... Diabetic retinopathy(DR),the main cause of irreversible blindness,is one of the most common complications of diabetes.At present,deep convolutional neural networks have achieved promising performance in automatic DR detection tasks.The convolution operation of methods is a local cross-correlation operation,whose receptive field de-termines the size of the local neighbourhood for processing.However,for retinal fundus photographs,there is not only the local information but also long-distance dependence between the lesion features(e.g.hemorrhages and exudates)scattered throughout the whole image.The proposed method incorporates correlations between long-range patches into the deep learning framework to improve DR detection.Patch-wise re-lationships are used to enhance the local patch features since lesions of DR usually appear as plaques.The Long-Range unit in the proposed network with a residual structure can be flexibly embedded into other trained networks.Extensive experimental results demon-strate that the proposed approach can achieve higher accuracy than existing state-of-the-art models on Messidor and EyePACS datasets. 展开更多
关键词 image classification medical image processing pattern recognition
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GNAS mutations suppress cell invasion by activating MEG3 in growth hormone–secreting pituitary adenoma
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作者 CHAO TANG CHUNYU ZHONG +4 位作者 JUNHAO ZHU FENG YUAN JIN YANG yong xu CHIYUAN MA 《Oncology Research》 SCIE 2024年第6期1079-1091,共13页
Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of sm... Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive tumors.However,the role of GNAS mutations in the invasiveness of GHPAs is unclear.GNAS mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing procedure.The expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with RT-qPCR.MEG3 was manipulated in GH3 cells using a lentiviral expression system.Cell invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western blotting.Finally,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and invasiveness.The invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type GNAS.Consistently,the invasiveness of mutant GNASexpressing GH3 cells decreased.MEG3 is uniquely expressed at high levels in GHPAs harboring mutated GNAS.Accordingly,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell invasion.Mechanistically,GNAS mutations inhibit EMT in GHPAs.MEG3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in vivo.Our data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway. 展开更多
关键词 GHPAs GNAS mutation MEG3 Β-CATENIN EMT
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Fuzzy Control Optimization of Loading Paths for Hydroforming of Variable Diameter Tubes
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作者 yong xu xuewei Zhang +4 位作者 Wenlong Xie Shihong Zhang Xinyue Huang Yaqiang Tian Liansheng Chen 《Computers, Materials & Continua》 SCIE EI 2024年第11期2753-2768,共16页
The design of the loading path is one of the important research contents of the tube hydroforming process.Optimization of loading paths using optimization algorithms has received attention due to the inefficiency of o... The design of the loading path is one of the important research contents of the tube hydroforming process.Optimization of loading paths using optimization algorithms has received attention due to the inefficiency of only finite element optimization.In this paper,the hydroforming process of 5A02 aluminum alloy variable diameter tube was as the research object.Fuzzy control was used to optimize the loading path,and the fuzzy rule base was established based on FEM.The minimum wall thickness and wall thickness reduction rate were determined as input membership functions,and the axial feeds variable value of the next step was used as output membership functions.The results show that the optimized loading path greatly improves the uniformity of wall thickness and the forming effect compared with the linear loading path.The round corner lamination rate of the tube is 91.2%under the fuzzy control optimized loading path,which was increased by 47.1%and 22.6%compared with linear loading Path 1 and Path 2,respectively.Based on the optimized loading path in the experiment,the minimum wall thickness of the variable diameter tube was 1.32 mm and the maximum thinning rate was 12.4%.The experimental results were consistent with the simulation results,which verified the accuracy of fuzzy control.The research results provide a reference for improving the forming quality of thin-walled tubes and plates. 展开更多
关键词 Variable diameter tubes finite element simulation HYDROFORMING fuzzy control
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Geometric prior guided hybrid deep neural network for facial beauty analysis
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作者 Tianhao Peng Mu Li +2 位作者 Fangmei Chen yong xu David Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第2期467-480,共14页
Facial beauty analysis is an important topic in human society.It may be used as a guidance for face beautification applications such as cosmetic surgery.Deep neural networks(DNNs)have recently been adopted for facial ... Facial beauty analysis is an important topic in human society.It may be used as a guidance for face beautification applications such as cosmetic surgery.Deep neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable performance.However,most existing DNN-based models regard facial beauty analysis as a normal classification task.They ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty analysis.To be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the decision.Inspired by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial parts.Additionally,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two branches.In model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric features.Experiments performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid network.To the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task. 展开更多
关键词 deep neural networks face analysis face biometrics image analysis
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Anoctamin 4 defines glucose-inhibited neurons in the ventromedial hypothalamus
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作者 Longlong Tu Yanlin He yong xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1177-1178,共2页
Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mai... Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body. 展开更多
关键词 inhibited MEDIAL ORGANS
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Dynamic SLAM Visual Odometry Based on Instance Segmentation:A Comprehensive Review
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作者 Jiansheng Peng Qing Yang +3 位作者 Dunhua Chen Chengjun Yang yong xu yong Qin 《Computers, Materials & Continua》 SCIE EI 2024年第1期167-196,共30页
Dynamic Simultaneous Localization and Mapping(SLAM)in visual scenes is currently a major research area in fields such as robot navigation and autonomous driving.However,in the face of complex real-world envi-ronments,... Dynamic Simultaneous Localization and Mapping(SLAM)in visual scenes is currently a major research area in fields such as robot navigation and autonomous driving.However,in the face of complex real-world envi-ronments,current dynamic SLAM systems struggle to achieve precise localization and map construction.With the advancement of deep learning,there has been increasing interest in the development of deep learning-based dynamic SLAM visual odometry in recent years,and more researchers are turning to deep learning techniques to address the challenges of dynamic SLAM.Compared to dynamic SLAM systems based on deep learning methods such as object detection and semantic segmentation,dynamic SLAM systems based on instance segmentation can not only detect dynamic objects in the scene but also distinguish different instances of the same type of object,thereby reducing the impact of dynamic objects on the SLAM system’s positioning.This article not only introduces traditional dynamic SLAM systems based on mathematical models but also provides a comprehensive analysis of existing instance segmentation algorithms and dynamic SLAM systems based on instance segmentation,comparing and summarizing their advantages and disadvantages.Through comparisons on datasets,it is found that instance segmentation-based methods have significant advantages in accuracy and robustness in dynamic environments.However,the real-time performance of instance segmentation algorithms hinders the widespread application of dynamic SLAM systems.In recent years,the rapid development of single-stage instance segmentationmethods has brought hope for the widespread application of dynamic SLAM systems based on instance segmentation.Finally,possible future research directions and improvementmeasures are discussed for reference by relevant professionals. 展开更多
关键词 Dynamic SLAM instance segmentation visual odometry
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How Does a University’s Computer Science Strength and Location Impact Its Total ChatGPT News?
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作者 Eileen Zhan Sumith Gunasekera yong xu 《Open Journal of Applied Sciences》 2024年第10期2973-2984,共12页
As AI, starting with ChatGPT has become increasingly prevalent in academic discussions, school especially, colleges have become hotspots of AI activities and debates. Colleges have the responsibility of addressing not... As AI, starting with ChatGPT has become increasingly prevalent in academic discussions, school especially, colleges have become hotspots of AI activities and debates. Colleges have the responsibility of addressing not only the academic, integrity-based concerns of students using AI for their homework, but also as the forebearers of new learning and technology, how AI will change their students’ futures and careers. In this study, we will explore the different factors, such as Computer Science Score and location, that might affect how much a college discusses AI, ChatGPT specifically. To demonstrate the validity of our research, we used self-collected data with our methods detailed below. 展开更多
关键词 AI ChatGPT Computer Science Statistical Analysis Location Impact
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Background modeling methods in video analysis: A review and comparative evaluation 被引量:4
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作者 yong xu Jixiang Dong +1 位作者 Bob Zhang Daoyun xu 《CAAI Transactions on Intelligence Technology》 2016年第1期43-60,共18页
Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially v... Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially video surveillance. An excellent background model can obtain a good foreground detection results. A lot of background modeling methods had been proposed, but few comprehensive evaluations of them are available. These methods suffer from various challenges such as illumination changes and dynamic background. This paper first analyzed advantages and disadvantages of various background modeling methods in video analysis applications and then compared their performance in terms of quality and the computational cost. The Change detection.Net (CDnet2014) dataset and another video dataset with different envi- ronmental conditions (indoor, outdoor, snow) were used to test each method. The experimental results sufficiently demonstrated the strengths and drawbacks of traditional and recently proposed state-of-the-art background modeling methods. This work is helpful for both researchers and engineering practitioners. Codes of background modeling methods evaluated in this paper are available atwww.yongxu.org/lunwen.html. 展开更多
关键词 Background modeling Video analysis Comprehensive evaluation
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2023中国阿尔茨海默病数据与防控策略 被引量:24
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作者 徐勇 王军 +13 位作者 王虹峥 王延江 刘肇瑞 郁金泰 周知 彭丹涛 顾栢俊 李坤成 侯清华 马辛 王晓明 王志稳 王惠芳 汤彬 《阿尔茨海默病及相关病杂志》 2023年第3期175-192,共18页
本报告汇总了阿尔茨海默病及痴呆相关领域现有的最新数据,分析了我国阿尔茨海默病的流行病学、疾病负担、诊断治疗、风险因素、康复护理和疾病筛查等各方面的现状、问题以及趋势,针对目前中国民众和政策制定者最关心的问题,例如:阿尔茨... 本报告汇总了阿尔茨海默病及痴呆相关领域现有的最新数据,分析了我国阿尔茨海默病的流行病学、疾病负担、诊断治疗、风险因素、康复护理和疾病筛查等各方面的现状、问题以及趋势,针对目前中国民众和政策制定者最关心的问题,例如:阿尔茨海默病基本数据是怎样的?为什么知晓率相对提高,但是患者就诊愿望相对不高?如何采用有效的措施来应对,等等,提出了目前阿尔茨海默病的防控策略。特别强调了要大力开发经过验证的早期筛查和诊断工具,提供更有效治疗的创新药物,以及鼓励和建立全国性属地化社会互助支持网络。本报告期望能对医学专业人士、患者、家属和照护者、政府政策制定人员、养老机构等有所帮助,能为阿尔茨海默病的防治工作提供支撑,为相关卫生政策的制定提供依据和建议,有助于提高公众对阿尔茨海默病的认识,以期缓解我国阿尔茨海默病疾病的整体负担,推动我国健康老龄化的实现。 展开更多
关键词 中国阿尔茨海默病数据 老龄化 老年痴呆 诊断与治疗 防控 策略 社会支持
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2022年中国阿尔茨海默病知晓与需求现状调查 被引量:5
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作者 徐勇 王军 +8 位作者 王虹峥 李坤成 王慧芳 王晓明 汤彬 乔立艳 李缨 李鹏 马辛 《阿尔茨海默病及相关病杂志》 2022年第4期265-277,共13页
目的:为了更加全面了解我国老年性痴呆(阿尔茨海默病)防治工作的现状及发展趋势,更加精准地为防治工作提供政策咨询及对策建议,开展了本次阿尔茨海默病知晓与需求现状调查。对象与方法:通过线上问卷,对18岁以上普通成年居民进行调查,居... 目的:为了更加全面了解我国老年性痴呆(阿尔茨海默病)防治工作的现状及发展趋势,更加精准地为防治工作提供政策咨询及对策建议,开展了本次阿尔茨海默病知晓与需求现状调查。对象与方法:通过线上问卷,对18岁以上普通成年居民进行调查,居民来自全国各个省市自治区和港澳台地区,调查总样本为20671人。结果:被调查人群阿尔茨海默病的总知晓率为95.9%,经统计学标化后为91.5%。不同人群对阿尔茨海默病的总知晓率存在一定差异;认为阿尔茨海默病或老年痴呆病可以预防的比例是87.9%;被调查居民觉得居家照护患者遇到的困难最主要表现在精力不够、照护能力不足和缺少专业的失智养老服务机构;患者的最主要的照护者是配偶,占47.9%,对阿尔茨海默病康复治疗内容了解的仅占23.3%;对合理安排患者营养知晓率为39%,在被调查人群中,主动愿意去医院就诊的比例只有12.9%,其中农村居民和低学历居民主动就诊愿望较低。结论:本次调查结果为更加精准地制定阿尔茨海默病防治对策,提供了重要的科学依据。 展开更多
关键词 调查 阿尔茨海默病 知晓率 需求现状
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硬段结构对含二硫键自修复聚氨酯性能的影响 被引量:3
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作者 张阳 周雨琪 +3 位作者 段文鹏 李博 许勇 孙妮娟 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第4期8-16,共9页
硬段结构的研究对指导制备兼顾力学性能与自修复性能的聚氨酯弹性体具有重要的意义。文中分别以4,4'-二苯基甲烷二异氰酸酯(MDI)、4,4'-二环己基甲烷二异氰酸酯(HMDI)、甲苯二异氰酸酯(TDI)、异佛尔酮二异氰酸酯(IPDI)及双(2-... 硬段结构的研究对指导制备兼顾力学性能与自修复性能的聚氨酯弹性体具有重要的意义。文中分别以4,4'-二苯基甲烷二异氰酸酯(MDI)、4,4'-二环己基甲烷二异氰酸酯(HMDI)、甲苯二异氰酸酯(TDI)、异佛尔酮二异氰酸酯(IPDI)及双(2-羟基乙基)二硫醚(HEDS)为硬段部分,聚己内酯二元醇为软段部分,制备了一系列含脂肪族二硫键的自修复聚氨酯,探究了不同异氰酸酯、硬段含量和扩链剂对其力学性能与自修复性能的影响。结果表明,对于异氰酸酯结构来讲,脂环族异氰酸酯制备的自修复聚氨酯具备更好的力学性能与自修复性能;对于脂环族异氰酸酯体系聚氨酯的硬段含量而言,一定范围越高,二硫键与氢键的含量也越高,越有利于材料的力学性能与自修复性能;对于扩链剂结构来讲,脂肪族二硫键主要是促进较高温度条件下的自修复性能,对于室温自修复性能起到的作用有限。 展开更多
关键词 脂肪族二硫键 自修复 聚氨酯 硬段
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MicroRNA-92a在胰腺癌中的表达及对肿瘤生长的影响 被引量:7
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作者 许勇 李波 +4 位作者 林强 钟昌桃 刘东 程愿 钟云昌 《中国现代医学杂志》 CAS 2019年第3期52-56,共5页
目的探讨人胰腺导管腺癌(PDAC)中microRNA-92a(miR-92a)的表达及对肿瘤细胞生长的影响。方法实时荧光定量聚合酶链反应(qRT-PCR)检测PDAC组织中miR-92a的表达水平;慢病毒转染PANC-1细胞构建miR-92a稳定敲除模型,克隆形成与流式细胞仪检... 目的探讨人胰腺导管腺癌(PDAC)中microRNA-92a(miR-92a)的表达及对肿瘤细胞生长的影响。方法实时荧光定量聚合酶链反应(qRT-PCR)检测PDAC组织中miR-92a的表达水平;慢病毒转染PANC-1细胞构建miR-92a稳定敲除模型,克隆形成与流式细胞仪检测细胞增殖凋亡;通过裸鼠皮下种植瘤模型检测下调miR-92a表达对肿瘤体内生长的影响;PCR及Western blotting检测miR-92a下游靶点DOC-2/DAB2结合蛋白(DAB2IP)在体外培养细胞中的表达水平;免疫组织化学检测DAB2IP在移植瘤组织中的表达水平。结果 miR-92a在PDAC组织中表达水平高于癌旁组织(P <0.05);miR-92a高表达的胰PDAC者肿瘤体积较miR-92a低表达者更大(P <0.05);下调miR-92a的表达能够抑制胰腺癌PANC-1细胞体外增殖能力,促进细胞凋亡,并抑制PANC-1细胞裸鼠皮下种植瘤的生长;下调miR-92a表达提高了PANC-1细胞内DAB2IP的表达水平及移植瘤组织内DAB2IP的表达水平(P <0.05)。结论 miR-92a在胰腺癌中表达升高,下调miR-92a的表达能使DAB2IP的表达下调而发挥抗肿瘤生长作用。 展开更多
关键词 胰腺肿瘤 MICRORNAS DOC-2/DAB2结合蛋白
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医疗设备消毒在新型冠状病毒肺炎救治中的重要性 被引量:5
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作者 雍旭 徐旭 《中国医疗设备》 2020年第S01期3-4,6,共3页
医疗设备表面的清洁消毒不规范易导致交叉感染的风险。在当前新冠疫情下,各家医院都在为疫情防治工作积极准备。通过分析近年来医疗设备的消毒方式、消毒频率、消毒剂的选择及消毒流程的控制,对新冠疫情中常见的医疗设备消毒模式进行汇... 医疗设备表面的清洁消毒不规范易导致交叉感染的风险。在当前新冠疫情下,各家医院都在为疫情防治工作积极准备。通过分析近年来医疗设备的消毒方式、消毒频率、消毒剂的选择及消毒流程的控制,对新冠疫情中常见的医疗设备消毒模式进行汇总,供大家参考。 展开更多
关键词 新冠肺炎 医疗设备 消毒 防护
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非接触式眼压计常见故障处理 被引量:1
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作者 雍旭 徐旭 夏辉 《中国医疗设备》 2020年第S01期56-57,共2页
本文旨在探讨非接触式眼压计的常见故障处理方案。通过阐述非接触式眼压计的测量原理,结合临床维修经验,对非接触式眼压计的维修与处理案例进行分析。通过非接触式眼压计的常见维修案例分析,为临床工程师提供了维修思路,同时也提升非接... 本文旨在探讨非接触式眼压计的常见故障处理方案。通过阐述非接触式眼压计的测量原理,结合临床维修经验,对非接触式眼压计的维修与处理案例进行分析。通过非接触式眼压计的常见维修案例分析,为临床工程师提供了维修思路,同时也提升非接触式眼压计临床使用的有效性、准确性和安全性。临床工程师应结合设备的临床使用情况,加强对设备的使用管理。 展开更多
关键词 眼压计 非接触式 故障处理 质量控制
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岩石物理和AVO在天然气水合物勘探中的应用 被引量:2
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作者 yong xu S. Chopra +2 位作者 赵京凤(译) 冯义钧(译) 葛洪魁(校) 《世界地震译丛》 2006年第6期45-53,共9页
与其他的孔隙流体相比,天然气水合物展示出独特的弹性。本文通过AVO研究孔隙流体,对天然气水合物填充岩石的AVO特性进行研究,并且探索了AVO在天然气水合物勘探中应用的潜力。
关键词 天然气水合物 岩石物理 AVO 应用 勘探 孔隙流体 流体相
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兼顾多动作与轻量化的仿生假肢手设计创成 被引量:1
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作者 雍旭 景晓蓓 +3 位作者 矢吹佳子 東郷俊太 横井浩史 李光林 《集成技术》 2022年第4期31-43,共13页
假肢手的动作数量与轻量化之间存在矛盾关系,为兼顾两者之间的平衡,满足假肢手多动作和轻量化的要求,该研究通过分析人手的16种日常抓取动作,设计了一种合理的电机驱动结构。该结构在四指中应用了多关节同时屈曲传动,在拇指中应用了定... 假肢手的动作数量与轻量化之间存在矛盾关系,为兼顾两者之间的平衡,满足假肢手多动作和轻量化的要求,该研究通过分析人手的16种日常抓取动作,设计了一种合理的电机驱动结构。该结构在四指中应用了多关节同时屈曲传动,在拇指中应用了定轨迹适应性传动,掌骨使用可自动切换为弧面和平面的对称弹性串联驱动式传动,以及配置五指的自动伸展,将这些机能融合在假肢手中,仅用3个电机实现了11种假肢手动作,达到了132.1 g的轻量化设计。该文还通过肌电信号结合神经网络算法,实现了假肢手直觉控制,并验证了其具有良好的抓取稳定性和操作性。 展开更多
关键词 轻量化 多动作 适应性抓取 对称弹性串联驱动式传动 神经网络算法 仿生假肢手
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Gambogic acid induces mitochondria-dependent apoptosis by modulation of Bcl-2 and Bax in mantle cell lymphoma JeKo-1 cells 被引量:18
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作者 Jingyan xu Min Zhou +7 位作者 Jian Ouyang Jing Wang Qiguo Zhang yong xu Yueyi xu Qian Zhang Xihui xu Hui Zeng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第2期183-191,共9页
Objective: To study the mechanisms in gambogic acid (GA) -induced JeKo-1 human Mantle Cell Lymphoma cell apoptosis in vitro. Methods: The proliferation of GA-treated JeKo-1 cells was measured by CCK-8 assay and Ki... Objective: To study the mechanisms in gambogic acid (GA) -induced JeKo-1 human Mantle Cell Lymphoma cell apoptosis in vitro. Methods: The proliferation of GA-treated JeKo-1 cells was measured by CCK-8 assay and Ki-67 immunocytochemical detection. Apopt0sis, cell cycle and mitochondrial membrane potential were measured by flow cytometric analysis. Caspase-3, -8 and -9 were detected by colorimetric assay. Bcl-2 and Bax were analyzed by Western blotting. Results: GA inhibited cell growth in a time- and dose- dependent manner. GA induces apoptosis in JeKo- 1 cells but not in normal bone marrow cells, which was involved in reducing the membrane potential of mitochondria, activating caspases-3, -8 and -9 and decreasing the ratio of Bd-2 and Bax without cell cycle arresting. Conclusions: GA induced apoptosis in human MCL JeKo-1 cells by regulating Bcl-2/Bax and activating caspase-3, -8 and -9 via mitochondrial pathway without affecting cell cycle. 展开更多
关键词 Gambogic acid JeKo-1 cells cell cycle arrest apoptosis membrane potential of mitochondria caspase-3 CASPASE-8 caspase-9 BAX BCL-2
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Experimental Realization of an Intrinsic Magnetic Topological Insulator 被引量:22
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作者 Yan Gong Jingwen Guo +21 位作者 Jiaheng Li Kejing Zhu Menghan Liao Xiaozhi Liu Qinghua Zhang Lin Gu Lin Tang Xiao Feng Ding Zhang Wei Li Canli Song Lili Wang Pu Yu Xi Chen Yayu Wang Hong Yao Wenhui Duan yong xu Shou-Cheng Zhang xucun Ma Qi-Kun xue Ke He 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期66-71,共6页
An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel ... An intrinsic magnetic topological insulator(TI) is a stoichiometric magnetic compound possessing both inherent magnetic order and topological electronic states. Such a material can provide a shortcut to various novel topological quantum effects but remained elusive experimentally for a long time. Here we report the experimental realization of thin films of an intrinsic magnetic TI, MnBi2Te4, by alternate growth of a Bi2Te3 quintuple layer and a MnTe bilayer with molecular beam epitaxy. The material shows the archetypical Dirac surface states in angle-resolved photoemission spectroscopy and is demonstrated to be an antiferromagnetic topological insulator with ferromagnetic surfaces by magnetic and transport measurements as well as first-principles calculations. The unique magnetic and topological electronic structures and their interplays enable the material to embody rich quantum phases such as quantum anomalous Hall insulators and axion insulators at higher temperature and in a well-controlled way. 展开更多
关键词 INTRINSIC MAGNETIC STOICHIOMETRIC MAGNETIC well-controlled WAY
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Molecular cloning,identification,and chromosomal localization of two MADS box genes in peach(Prunus persica) 被引量:13
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作者 Lin Zhang yong xu Rongcai Ma 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第6期365-372,共8页
MADS box proteins play an important role in floral development. To find genes involved in the floral transition of Prunus species, cDNAs for two MADS box genes, PpMADS1 and PpMADSIO, were cloned using degenerate prime... MADS box proteins play an important role in floral development. To find genes involved in the floral transition of Prunus species, cDNAs for two MADS box genes, PpMADS1 and PpMADSIO, were cloned using degenerate primers and 5'- and T-RACE based on the sequence database of P. persiea and P. duleis. The full length of PpMADS1 cDNA is 1,071 bp containing an open reading frame (ORF) of 717 bp and coding for a polypeptide of 238 amino acid residues. The full length of PpMADSIO cDNA is 937 bp containing an ORF of 633 bp and coding for a polypeptide of 210 amino acid residues. Sequence comparison revealed that PpMADS1 and PpMADSIO were highly homologous to genes API and PI in Arabidopsis, respectively. Phylogenetic analysis indicated that PpMADS1 belongs to the euAP1 clade of class A, and PpMADSIO is a member of GLO/PI clade of class B. RT-PCR analysis showed that PpMADS1 was expressed in sepal, petal, carpel, and fruit, which was slightly different from the expression pattern ofAPl; PpMADS10 was expressed in petal and stamen, which shared the same expression pattern as PI. Using selective mapping strategy, PpMADSI was assigned onto the Binl:50 on the G1 linkage group between the markers MCO44 and TSA2, and PpMADSIO onto the Bin1:73 on the same linkage group between the markers Lap- 1 and FGA8. Our results provided the basis for further dissection of the two MADS box gene function. 展开更多
关键词 peach (Prunus persica) flower development MADS box gene selective mapping
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