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Overview and progress of X-nuclei magnetic resonance imaging in biomedical studies
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作者 Gengxin Wang Hongyi Yang +3 位作者 Juan Li Jie Wen Kai Zhong Changlin Tian 《Magnetic Resonance Letters》 2023年第4期327-343,共17页
Proton nuclear(^(1)H)is the observed nucleus on which most magnetic resonance imaging(MRI)applications depend.Most traditional^(1)H MRI can provide structural and functional information about organisms,while various n... Proton nuclear(^(1)H)is the observed nucleus on which most magnetic resonance imaging(MRI)applications depend.Most traditional^(1)H MRI can provide structural and functional information about organisms,while various non-proton nuclei(X-nuclei)MRI can provide more metabolic information.However,due to the relatively poor signal-to-noise ratio(SNR)of X-nuclei MRI,their applications are quite rare compared to^(1)H.Benefit from the rapid developments of MRI hardware and software technologies,X-nuclei MRI has recently attracted increasing interests in biomedical research.This review firstly introduces some current methods to improve the SNR of X-nuclei MRI.Secondly,this review describes biomedical applications of X-nuclei MRI,especially focusing on the current use of X-nuclei(^(13)C,^(17)O,^(19)F,^(23)Na and^(31)P)MRI to study related diseases in different organs,including the brain,liver,kidney,heart and bone.Finally,perspectives studies on X-nuclei imaging and its potential applications are described in biomedical research. 展开更多
关键词 Magnetic resonance imaging X-nuclei BIOMEDICAL ^(13)C ^(17)O ^(19)F ^(23)Na ^(31)p
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慢性肾功能不全患者甲状旁腺素水平与心电图V1导联P波终末电势的相关性及对左心室舒张功能障碍的预测价值
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作者 高文强 吴淑红 +2 位作者 赵晓霞 李璐 郝志敏 《中国心血管病研究》 CAS 2024年第2期155-160,共6页
目的探析慢性肾功能不全患者甲状旁腺素(PTH)水平与心电图V1导联P波终末电势(PTFv1)的相关性,并分析二者对左心室舒张功能障碍的预测价值。方法纳入2021年10月至2023年3月自黄浦区肿瘤防治院150例慢性肾功能不全患者为研究对象,所有患... 目的探析慢性肾功能不全患者甲状旁腺素(PTH)水平与心电图V1导联P波终末电势(PTFv1)的相关性,并分析二者对左心室舒张功能障碍的预测价值。方法纳入2021年10月至2023年3月自黄浦区肿瘤防治院150例慢性肾功能不全患者为研究对象,所有患者入院时均接受PTH水平检测,并完善心电图和超声心动图检查,观察慢性肾功能不全患者PTH水平与心电图检查指标、超声心动图检查指标的相关性。统计所有患者左心室舒张功能障碍发生状况,并将其分为功能障碍组与功能正常组,对比两组基线资料及PTH水平与PTFv1,采用多因素logistic回归分析慢性肾功能不全患者左心室舒张功能障碍的影响因素,并绘制受试者工作特征(ROC)曲线分析PTH水平与PTFv1对左心室舒张功能障碍的预测价值。结果150例慢性肾功能不全患者PTH水平为(159.64±76.32)pg/ml,PTFv1为[-0.3(-0.2,-0.3)]mm·s,左心房内径(LAD)为(37.42±4.68)mm,左心室内径(LVDD)为(48.25±4.39)mm;Pearson相关性分析显示,慢性肾功能不全患者PTH水平与PTFv1呈负相关(r=-0.443,P<0.05),与LAD、LVDD呈正相关(r=0.345、0.523,P<0.05);150例慢性肾功能不全患者中发生左心室舒张功能障碍71例,占47.33%;功能障碍组LAD、LVDD、PTH水平高于功能正常组,PTFv1低于功能正常组(P<0.05);Logistic回归分析显示,LAD、LVDD、PTH是慢行肾功能不全患者发生左心室舒张功能障碍的危险因素(OR>1,P<0.05),PTFv1是保护因素(OR<1,P<0.05);ROC曲线显示,PTH、PTFv1对慢性肾功能不全患者发生左心室舒张功能障碍具有一定预测价值(AUC=0.863、0.753),联合预测价值更高(AUC=0.869)。结论慢性肾功能不全患者PTH水平与PTFv1呈负相关,PTH水平越高,左心房及左心室越大,临床可通过检测PTH水平预测患者左心室舒张功能障碍。 展开更多
关键词 慢性肾功能不全 甲状旁腺素 心电图v1导联p波终末电势 左心室舒张功能障碍
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^(32)P敷贴+曲安奈德序贯治疗皮肤瘢痕疙瘩近期疗效及其VTIQ评估的临床研究
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作者 郑惠瑜 邓咏梅 +5 位作者 张金山 姚红霞 刘韬 李园 卢健林 袁晓燕 《广州医科大学学报》 2024年第2期19-25,共7页
目的:探讨^(32)P敷贴近距离放疗+瘤体内注射曲安奈德混合液序贯综合治疗皮肤瘢痕疙瘩的近期疗效及声触诊组织成像定量技术(VTIQ)对其疗效评估的初步临床应用。方法:收集2022年6月至2023年1月对在本院核医学门诊就诊的23例皮肤瘢痕疙瘩患... 目的:探讨^(32)P敷贴近距离放疗+瘤体内注射曲安奈德混合液序贯综合治疗皮肤瘢痕疙瘩的近期疗效及声触诊组织成像定量技术(VTIQ)对其疗效评估的初步临床应用。方法:收集2022年6月至2023年1月对在本院核医学门诊就诊的23例皮肤瘢痕疙瘩患者(观察组),采用^(32)P敷贴近距离放疗+瘤体内注射曲安奈德混合液序贯综合方法进行治疗,治疗前、后行改良法温哥华瘢痕量表(VSS)评分,同时对病灶进行声触诊组织成像定量技术(VTIQ)测定剪切波速度(SWV,m/s),用以评估其近期疗效;收集本院核医学门诊2020年6月至2023年1月仅行^(32)P敷贴近距离放疗的共29例皮肤瘢痕疙瘩患者作为对照组,比较两组疗效。结果:(1)对23例观察组患者的34个病灶共完成了102次注射和68次^(32)P敷贴近距离放疗,总有效率(治愈+显效)为79.41%(27/34),对照组29例患者的42个病灶共进行了173次^(32)P敷贴近距离放疗,总有效率为80.95%(34/42),两组总有效率差异无统计学意义(χ^(2)=0.028,P=0.867);观察组的每病灶^(32)P治疗次数(次数/病灶)和总疗程(d)较对照组显著减少[2.00(2.00,2.00)比4.00(3.25,5.00);66.00(63.25,72.00)比169.0(132.2,194.0),P<0.01)]。(2)观察组治疗后SWVmax(m/s)和SWVmean(m/s)皆较治疗前显著下降(5.79±3.05比6.75±3.80,4.68±1.92比5.35±2.38,P<0.05),治疗后改良法VSS评分(分)较治疗前减少(9.04±1.85比11.03±2.33,P<0.05),治疗前SWVmean与改良法VSS评分呈一定程度的相关性(r=0.44,P<0.05)。结论:^(32)P敷贴近距离放疗+瘤体内注射曲安奈德混合液序贯治疗皮肤瘢痕疙瘩的近期疗效满意,与单独^(32)P敷贴相比,在不降低疗效的同时显著减少了^(32)P敷贴治疗次数和缩短了总疗程;声触诊组织成像定量技术(VTIQ)可望为早期疗效评估提供敏感、客观的定量指标。 展开更多
关键词 瘢痕疙瘩 ^(32)p敷贴 近距离放射治疗 曲安奈德 声触诊组织成像定量技术
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2P DC 1500 V框架隔离开关设计
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作者 黄银芳 蒋顾平 《现代建筑电气》 2024年第5期21-25,共5页
2P DC 1500 V框架隔离开关适用于光伏、储能系统。这类产品相比老产品而言更具成本上的优势。产品主要的设计改进点为:修改机构连杆加大开距;主弧触头、窄缝灭弧技术通过临界电流试验;电场磁场的仿真设计专用灭弧以及绝缘技术保证灭弧... 2P DC 1500 V框架隔离开关适用于光伏、储能系统。这类产品相比老产品而言更具成本上的优势。产品主要的设计改进点为:修改机构连杆加大开距;主弧触头、窄缝灭弧技术通过临界电流试验;电场磁场的仿真设计专用灭弧以及绝缘技术保证灭弧可靠通过电寿命试验。经试验验证,2P DC 1500 V框架隔离开关符合标准要求。 展开更多
关键词 2p DC1500 v 框架 隔离开关
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卡车48V P1混动系统模型及控制策略开发
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作者 金质儒 沈媛媛 +2 位作者 梁凤标 韩四海 王舒然 《重型汽车》 2024年第3期4-6,共3页
基于某6×4重型载货卡车及MC13H发动机,设计开发了一种用于提高中载及重载卡车能效的48VP1基于规则的同轴混动控制策略以及混合动力系统整车模型,并对该混动系统进行了参数优化及模型验证,开展了CHTC_TT循环路谱下混动P1架构的整车... 基于某6×4重型载货卡车及MC13H发动机,设计开发了一种用于提高中载及重载卡车能效的48VP1基于规则的同轴混动控制策略以及混合动力系统整车模型,并对该混动系统进行了参数优化及模型验证,开展了CHTC_TT循环路谱下混动P1架构的整车性能特征研究。研究表明:该模型具有较高准确性,其混动控制策略可以有效降低整车油耗,较原车油耗可降低4.83%。在CHTC_TT路谱下电机超车助力效率最高,主要依靠制动回馈进行发电。该混动控制策略已在实际重载卡车上得到应用,具有广泛的应用前景。 展开更多
关键词 卡车 p1架构 48v混动 同轴 控制策略
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Nuclear imaging for functional evaluation and theragnosis in liver malignancy and transplantation 被引量:3
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作者 Jae Seon Eo Jin Chul Paeng Dong Soo Lee 《World Journal of Gastroenterology》 SCIE CAS 2014年第18期5375-5388,共14页
Currently,nuclear imaging such as positron emission tomography(PET)and single photon emission computed tomography(SPECT)is increasingly used in the management of liver malignancy.18F-fluorodeoxyglucose(FDG)-PET is the... Currently,nuclear imaging such as positron emission tomography(PET)and single photon emission computed tomography(SPECT)is increasingly used in the management of liver malignancy.18F-fluorodeoxyglucose(FDG)-PET is the most widely used nuclear imaging in liver malignancy as in other cancers,and has been reported to be effective in diagnosis,response monitoring,recurrence evaluation,and prognosis prediction.Other PET imaging such as 11C-acetate PET is also used complementarily to FDG-PET in diagnosis of liver malignancy.Additionally,image-based evaluation of regional hepatic function can be performed using nuclear imaging.Those imaging modalities are also effective for candidate selection,treatment planning,and perioperative evaluation in liver surgery and transplantation.Recently,nuclear imaging has been actively adopted in the transarterial radioembolization therapy of liver malignancy,according to the concept of theragnosis.With the development of new hybrid imaging technologies such as PET/magnetic resonance imaging and SPECT/CT,nuclear imaging is expected to be more useful in the management of liver malignancy,particularly regarding liver surgery and transplantation.In this review,the efficacy and roles of nuclear imaging methods in diagnosis,transplantation and theragnosis are discussed. 展开更多
关键词 Nuclear imaging Liver MALIGNANCY TRANSpLANTATION p
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铁死亡在HIV-1 gp120 V3环致小胶质细胞炎症中的作用机制研究 被引量:2
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作者 干李梦 王琳琳 +6 位作者 左勤 颜学勤 潘锐 王会丽 唐海杰 付咏梅 董军 《中国病理生理杂志》 CAS CSCD 北大核心 2023年第5期819-826,共8页
目的:探讨人类免疫缺陷病毒1型(human immunodeficiency virus type 1,HIV-1)gp120 V3环致CHME-5小胶质细胞炎症反应与铁死亡的关系,并观察p53和铁死亡对该炎症反应的影响及可能机制。方法:体外培养人源CHME-5小胶质细胞,设立空白组、... 目的:探讨人类免疫缺陷病毒1型(human immunodeficiency virus type 1,HIV-1)gp120 V3环致CHME-5小胶质细胞炎症反应与铁死亡的关系,并观察p53和铁死亡对该炎症反应的影响及可能机制。方法:体外培养人源CHME-5小胶质细胞,设立空白组、随机肽段组、HIV-1 gp120 V3环组、HIV-1 gp120 V3环+ferrostatin-1(Fer-1;铁死亡抑制剂)组和HIV-1 gp120 V3环+pifithrin-α(p53抑制剂)组。分别采用HIV-1 gp120 V3环(终浓度2 mg/L)和随机肽段(终浓度2 mg/L)处理CHME-5细胞24 h;Fer-1(终浓度20μmol/L)和pifithrin-α(终浓度10μmol/L)预处理CHME-5细胞2 h,HIV-1 gp120 V3环(终浓度2 mg/L)再处理24 h。ELISA法检测各组细胞上清液中炎症因子水平;Western blot法检测铁死亡相关蛋白[转铁蛋白受体1(transferrin receptor-1,TFR-1)、溶质载体家族7成员11(solute carrier family 7 member 11,SLC7A11)和谷胱甘肽过氧化物酶4(glutathione peroxidase 4,GPX4)]及p53的蛋白表达;酶标仪法检测细胞内亚铁离子(Fe2+)和谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性。结果:(1)ELISA结果显示,与对照组相比,gp120 V3环组炎症因子白细胞介素1β(interleukin-1β,IL-1β)、IL-6和肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)水平显著升高(P<0.01);与gp120 V3环组相比,gp120 V3环+Fer-1组和gp120 V3环+pifithrin-α组炎症因子IL-1β、IL-6和TNF-α水平显著下降(P<0.01);(2)Western blot结果显示,与对照组相比,gp120 V3环组蛋白p53显著上调(P<0.01),铁死亡相关蛋白TFR-1显著上调(P<0.01),SLC7A11和GPX4显著下调(P<0.01);与gp120 V3环组相比,gp120 V3环+pifithrin-α组铁死亡相关蛋白TFR-1显著下降(P<0.05),SLC7A11和GPX4蛋白显著升高(P<0.05);(3)与对照组相比,gp120 V3环组Fe2+含量显著增加(P<0.01),GSH-Px活性显著降低(P<0.01);与gp120 V3环组相比,gp120 V3环+Fer-1组和gp120 V3环+pifithrin-α组Fe2+含量显著下降(P<0.05),GSH-Px活性显著升高(P<0.01)。结论:HIV-1 gp120 V3环致CHME-5小胶质细胞炎症中存在铁死亡,且抑制铁死亡能减轻炎症。HIV-1 gp120 V3环致CHME-5小胶质细胞炎症与p53蛋白调控铁死亡有关,抑制p53可减轻铁死亡和炎症反应。 展开更多
关键词 HIv相关神经认知障碍 HIv-1 gp120 v3环 铁死亡 p53蛋白 神经炎症
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基于p范数的E-3DTV高光谱去噪模型
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作者 罗琼 韩志 +1 位作者 陈希爱 唐延东 《计算机应用与软件》 北大核心 2023年第7期222-228,304,共8页
三维全变分(3DTV)编码了高光谱图像的局部平滑结构,通过假设沿着空间和频谱模式计算的梯度图具有独立且相同的稀疏结构来计算该正则项。然而,实际情况下梯度图通常在所有波段上具有不同而相关的稀疏结构。增强的3DTV正则(E-3DTV)的提出... 三维全变分(3DTV)编码了高光谱图像的局部平滑结构,通过假设沿着空间和频谱模式计算的梯度图具有独立且相同的稀疏结构来计算该正则项。然而,实际情况下梯度图通常在所有波段上具有不同而相关的稀疏结构。增强的3DTV正则(E-3DTV)的提出很好地解决了这个问题。除了对图像本身的知识编码以外,对其中复杂而未知的噪声进行正确的建模也是至关重要的。然而,与E-3DTV有关的工作目前只对基于1范数的噪声模型进行了探索。为了进一步提高对高光谱中复杂未知噪声的拟合能力,提出基于p范数的E-3DTV去噪模型,实验证明所提出的方法优于基于1范数的方法并在所有竞争方法中收获了最优的结果。 展开更多
关键词 高光谱图像去噪 增强三维全变分 p范数
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基于p-V图特征的往复压缩机缸内易损件故障诊断技术研究—模拟实验 被引量:2
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作者 杨毅帆 祝钟青 +3 位作者 张戟 陈青松 肖植 吴伟烽 《压缩机技术》 2023年第1期11-18,共8页
往复压缩机是化工工艺生产流程中的核心设备,具有易损件多,持续运行时间长的特点。其缸内的易损件主要包括气阀、活塞环和填函等部件,因易损件发生故障而导致的非计划性停机,往往会对企业造成较大的经济损失甚至引发严重的安全事故。理... 往复压缩机是化工工艺生产流程中的核心设备,具有易损件多,持续运行时间长的特点。其缸内的易损件主要包括气阀、活塞环和填函等部件,因易损件发生故障而导致的非计划性停机,往往会对企业造成较大的经济损失甚至引发严重的安全事故。理论上,基于p-V图的故障诊断可准确识别缸内易损件故障,同时缸内易损件的故障往往表现为泄漏。模拟实验,研究了缸内易损件在泄漏故障下的p-V图特征,结果表明提取p-V图膨胀过程综合指数(指征膨胀过程曲线倾斜程度)可以用于识别缸内易损件是否发生泄漏故障。 展开更多
关键词 往复压缩机 故障模拟实验 p-v 膨胀过程综合指数
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敦煌本藏文星占文书P.3288V研究之四——宿曜择吉法释读 被引量:1
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作者 刘英华 拉毛吉 《西藏大学学报(社会科学版)》 北大核心 2023年第1期93-99,共7页
敦煌藏文文书P.3288V是一部择吉、占卜、堪舆杂钞本,是已知年代最早的藏历算文献实物。其星占部分所记述的吉日,及逆、违、毁(灭)和魔日等四凶日,属于藏历五行算内容,对研究藏历算历史与汉藏文化交流具有重要价值。文章选录这部分内容,... 敦煌藏文文书P.3288V是一部择吉、占卜、堪舆杂钞本,是已知年代最早的藏历算文献实物。其星占部分所记述的吉日,及逆、违、毁(灭)和魔日等四凶日,属于藏历五行算内容,对研究藏历算历史与汉藏文化交流具有重要价值。文章选录这部分内容,根据藏历算知识和藏历算经典中的相关记载,对该文书中残缺和无法辨识的文字做了推拟重构,在此基础上译为汉语并做初步探讨。 展开更多
关键词 敦煌文书 藏历算 星占术(五行算) 七曜 二十八宿 p.3288v
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V-P分流术不同穿刺位置联合同期颅骨修补术在颅脑损伤脑积水患者中的应用 被引量:2
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作者 申剑波 茹小红 《中国实用神经疾病杂志》 2023年第10期1269-1274,共6页
目的探讨脑室-腹腔(V-P)分流术不同穿刺位置联合同期颅骨修补术在颅脑损伤脑积水患者中的效果及对凝血功能、粒系集落刺激因子(G-CSF)、肿瘤坏死因子-α(TNF-α)的影响。方法回顾性分析2020-06—2022-06晋城市人民医院121例颅脑损伤脑... 目的探讨脑室-腹腔(V-P)分流术不同穿刺位置联合同期颅骨修补术在颅脑损伤脑积水患者中的效果及对凝血功能、粒系集落刺激因子(G-CSF)、肿瘤坏死因子-α(TNF-α)的影响。方法回顾性分析2020-06—2022-06晋城市人民医院121例颅脑损伤脑积水患者临床资料,根据手术方案分为A组(n=61)和B组(n=60),分别行V-P分流术(副三角区穿刺)+颅骨修补术、V-P分流术(侧脑室三角区穿刺)+颅骨修补术。统计2组脑积水改善情况、并发症、预后,对比术前、术后凝血功能、G-CSF、TNF-α、脑灌注情况、神经功能评分(NIHSS)。结果A组脑积水改善总有效率81.97%与B组80.00%比较,差异无统计学意义(P>0.05)。术后3 d、7 d A组血清APTT、PT水平低于B组,Fbg水平高于B组(P<0.05)。术后1个月A组血清G-CSF水平高于B组,TNF-α水平低于B组(P<0.05)。术前2组NIHSS评分、ICP、CCP比较,差异无统计学意义(P>0.05),术后1个月、3个月2组NIHSS评分、ICP低于术前,CCP高于术前(P<0.05)。A组并发症发生率(6.56%)低于B组(20.00%,P<0.05)。术后3个月,A组预后优良率(66.67%)与B组(67.24%)比较,差异无统计学意义(P>0.05)。结论V-P分流术不同穿刺位置联合同期颅骨修补术治疗颅脑损伤脑积水疗效相当,特别是副三角区穿刺,可减少并发症,降低血清G-CSF、TNF-α水平,且对凝血功能影响较小。 展开更多
关键词 颅脑损伤 脑积水 颅骨修补术 v-p分流术 粒系集落刺激因子 肿瘤坏死因子-Α
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高速公路V2V通信中C-V2X和IEEE802.11p通信协议的比较 被引量:1
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作者 刘轶 《交通世界》 2023年第12期1-3,10,共4页
在概述C-V2X和IEEE802.11p通信技术发展概况及特征的基础上,依托OMNET++仿真平台,采用Veins和SUMO联合仿真技术建立起高速公路通信仿真场景,并进行C-V2X和IEEE802.11p通信协议丢包率和端到端时延等参数值的计算分析与性能比测。结果表明... 在概述C-V2X和IEEE802.11p通信技术发展概况及特征的基础上,依托OMNET++仿真平台,采用Veins和SUMO联合仿真技术建立起高速公路通信仿真场景,并进行C-V2X和IEEE802.11p通信协议丢包率和端到端时延等参数值的计算分析与性能比测。结果表明,C-V2X通信技术是高速公路新型信息基础设施建设的重要部分,因具备高可靠、高传输效率、低时延等优势,而成为国际主流公路通信标准;C-V2X和IEEE802.11p通信技术在安全应用时延方面均满足要求,但C-V2X在丢包率方面比IEEE802.11p更优。 展开更多
关键词 v2v通信 C-v2X IEEE802.11p 通信协议
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基于虚拟电阻的复杂直流网络P-V下垂控制方法
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作者 王辞喻 赵兴勇 《科学技术与工程》 北大核心 2023年第31期13423-13429,共7页
对于复杂直流网络控制困难的问题,现有研究很少有基于虚拟电阻的下垂系数计算方法,设计了一种将复杂电网等效为简单放射状网络的方法,并提出一种基于虚拟电阻的功率-电压(P-V)下垂控制方法。首先,定义虚拟母线及虚拟节点,将节点分为3类... 对于复杂直流网络控制困难的问题,现有研究很少有基于虚拟电阻的下垂系数计算方法,设计了一种将复杂电网等效为简单放射状网络的方法,并提出一种基于虚拟电阻的功率-电压(P-V)下垂控制方法。首先,定义虚拟母线及虚拟节点,将节点分为3类并分别处理,得到一个等效的放射状电网拓扑结构。然后,根据简化结果推导出P-V下垂系数的计算公式,得出控制策略。仿真结果表明了所提电网等效方法和基于虚拟电阻的P-V下垂控制策略的有效性和可行性。 展开更多
关键词 虚拟节点 虚拟电阻 p-v下垂控制 复杂直流系统 网络等效化简
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Alpha-fetoprotein-targeted reporter gene expression imaging in hepatocellular carcinoma 被引量:7
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作者 Kwang Il Kim Hye Kyung Chung +2 位作者 Ju Hui Park Yong Jin Lee Joo Hyun Kang 《World Journal of Gastroenterology》 SCIE CAS 2016年第27期6127-6134,共8页
Hepatocellular carcinoma(HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic... Hepatocellular carcinoma(HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene's expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumorspecific reporter gene expression driven by an alphafetoprotein(AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment. 展开更多
关键词 ALpHA-FETOpROTEIN HEpATOCELLULAR carcinoma Molecular imaging REpORTER gene TUMOR-SpECIFIC enhancer/p
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腹腔镜下V-P分流术手术的护理配合
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作者 金晓华 费建平 费雯雯 《医药前沿》 2023年第10期13-15,共3页
目的:总结腹腔镜下V-P分流术的(脑室腹腔分流术)手术室护理与方法。方法:分析昆山市中医医院2018年1月—2021年12月23例V-P分流术手术配合,探讨手术医师与麻醉医师操作空间的合理布局,精心规划手术器械台的布局,精心设计手术器械传递路... 目的:总结腹腔镜下V-P分流术的(脑室腹腔分流术)手术室护理与方法。方法:分析昆山市中医医院2018年1月—2021年12月23例V-P分流术手术配合,探讨手术医师与麻醉医师操作空间的合理布局,精心规划手术器械台的布局,精心设计手术器械传递路径。结果:成功完成23例V-P分流术手术配合,平均手术时间(106.42±25.60)min,术后2 d复查,14例脑室不同程度缩小,所有患者症状都有不同程度减轻。结论:腹腔镜下V-P分流术、颅脑手术与腹部手术存在时间与空间的交集;手术人员、仪器设备以及器械台的合理布局,手术护士空间管理能力的培训,加强医护合作性学习,保障手术过程的流畅性,从而防止术后感染、提高手术质量。 展开更多
关键词 腹腔镜 脑积水分流术 护理配合 医护合作性学习
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EfficientNetV2 Model for Plant Disease Classification and Pest Recognition
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作者 R.S.Sandhya Devi V.RVijay Kumar P.Sivakumar 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期2249-2263,共15页
Plant disease classification and prevention of spreading of the disease at earlier stages based on visual leaves symptoms and Pest recognition through deep learning-based image classification is in the forefront of re... Plant disease classification and prevention of spreading of the disease at earlier stages based on visual leaves symptoms and Pest recognition through deep learning-based image classification is in the forefront of research.To perform the investigation on Plant and pest classification,Transfer Learning(TL)approach is used on EfficientNet-V2.TL requires limited labelled data and shorter training time.However,the limitation of TL is the pre-trained model network’s topology is static and the knowledge acquired is detrimentally overwriting the old parameters.EfficientNet-V2 is a Convolutional Neural Network(CNN)model with significant high speed learning rates across variable sized datasets.The model employs a form of progressive learning mechanism which expands the network topology gradually over the course of training process improving the model’s learning capacity.This provides a better interpretability of the model’s understanding on the test domains.With these insights,our work investigates the effectiveness of EfficienetV2 model trained on a class imbalanced dataset for plant disease classification and pest recognition by means of combining TL and progressive learning approach.This Progressive Learning for TL(PL-TL)is used in our work consisting of 38 classes of PlantVillage dataset of crops and fruit species,5 classes of cassava leaf diseases and another dataset with around 102 classes of crop pest images downloaded from popular dataset platforms,though it is not a benchmark dataset.To test the predictability rate of the model in classifying leaf diseases with similar visual symptoms,Mix-up data augmentation technique is used at the ratio of 1:4 on corn and tomato classes which has high probability of misinterpretation of disease classes.Also,the paper compares the TL approach performed on the above mentioned three types of data set using well established CNN based Inceptionv3,and Vision Transformer a non-CNN model.It clearly depicts that EfficientNetV2 has an outstanding performance of 99.5%,97.5%,80.1%on Cassava,PlantVillage and IP102 datasets respectively at a faster rate irrespective of the data size and class distribution as compared to Inception-V3 and ViT models.The performance metrics in terms of accuracy,precision,f1-score is also studied. 展开更多
关键词 image classification transfer learning efficientNetv2 mix-up data augmentation inception v3
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基于Python语言辅助化工热力学教学
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作者 张建兰 崔健 +2 位作者 蔡江涛 汪广恒 张亚婷 《广州化工》 CAS 2024年第1期235-237,251,共4页
化工热力学由于公式繁多,概念抽象,计算求解过程中通常要用到迭代试差而成为化工专业课程中教学难度较大的课程之一。随着计算机技术的迅速发展与应用,将其融入化工热力学教学已经成为培养新时代化工专业人才的必然趋势。结合近年来流行... 化工热力学由于公式繁多,概念抽象,计算求解过程中通常要用到迭代试差而成为化工专业课程中教学难度较大的课程之一。随着计算机技术的迅速发展与应用,将其融入化工热力学教学已经成为培养新时代化工专业人才的必然趋势。结合近年来流行的Python语言及其优势,重点介绍其在p-V-T关系计算中的应用实例。通过Python语言编程解决化工热力学中的计算问题,可以有效解决化工热力学教学中的难点问题,很大程度提升课堂的教学质量和效率。 展开更多
关键词 pynthon语言 化工热力学教学 p-v-T关系 迭代试差
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MRI联合交感皮肤反应及经颅超声诊断帕金森病与多系统萎缩P型的研究
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作者 徐天阳 刘恒方 +3 位作者 郭亚培 石磊 张敏 李金凤 《中国实用神经疾病杂志》 2024年第4期403-408,共6页
目的 探讨头部常规磁共振(MRI)联合交感神经皮肤反应(SSR)及经颅超声成像(TCS)用于诊断帕金森病(PD)与多系统萎缩P型(MSA-P型)的价值。方法 收集2019-01—2022-06郑州大学第五附属医院临床确诊且具有完整资料的22例MSA-P型患者和29例PD... 目的 探讨头部常规磁共振(MRI)联合交感神经皮肤反应(SSR)及经颅超声成像(TCS)用于诊断帕金森病(PD)与多系统萎缩P型(MSA-P型)的价值。方法 收集2019-01—2022-06郑州大学第五附属医院临床确诊且具有完整资料的22例MSA-P型患者和29例PD患者,均行头部常规MRI、SSR和TCS检查,采用ROC曲线评价头部MRI、SSR和TCS诊断MSA-P型和PD患者的临床价值。结果 壳核裂隙征具有影像特异性,MSA-P型组远高于PD组(P<0.05)。MSA-P型组上、下肢SSR平均起始潜伏期延长,平均波幅降低与PD组比较差异有统计学意义(P<0.01)。2组黑质强回声面积、黑质强回声总面积与中脑总面积比值比较差异有统计学意义(P<0.01)。ROC曲线下壳核裂隙征有高特异性(96.8%),SSR上肢潜伏期有高敏感性(88.2%),SN强回声面积诊断价值最高,曲线下面积(AUC)为0.881;头部MRI联合SSR、TCS用于预测两种疾病的敏感度为72.1%,AUC为0.913。结论 分析头部MRI检查结果,早期进行SSR、TCS检查可提高对MSA-P型与PD患者的诊断率。 展开更多
关键词 交多系统萎缩-p 帕金森病 感神经皮肤反应 常规磁共振 经颅超声成像
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Differences in functional magnetic resonance imaging following cutaneous and routine acupuncture at different acupoints 被引量:1
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作者 Yangjia Lu Junxian Wu +4 位作者 Yanqi Zou Junqi Chen Baoci Shan Jiarong Chen Yong Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第15期1169-1174,共6页
Few studies have examined the effects of different stimuli at a single acupoint using functional magnetic resonance imaging.The present study applied acupuncture at the Neiguan(PC 6),Waiguan(SJ 5),Zhigou(SJ 6) a... Few studies have examined the effects of different stimuli at a single acupoint using functional magnetic resonance imaging.The present study applied acupuncture at the Neiguan(PC 6),Waiguan(SJ 5),Zhigou(SJ 6) and Yanglingquan(GB 34) acupoints in healthy volunteers.fMRI was used to examine the activation of brain areas in response to different types of acupuncture(cutaneous or routine acupuncture) at each acupoint.There were no significant differences in the distribution of activation in the regions of interest between cutaneous and routine acupuncture at the Neiguan,Waiguan,and Zhigou acupoints,but some differences were observed between the two methods of acupuncture at the Yanglingquan acupoint.There were no significant differences in the intensity of induced activation between cutaneous and routine acupuncture at the Neiguan,Zhigou and Yanglingquan acupoints,but the activation intensity in the right cerebellum induced by routine acupuncture at the Waiguan acupoint was greater than that induced by cutaneous acupuncture.Results confirmed that cutaneous and routine acupuncture at the Neiguan,Waiguan,Zhigou and Yanglingquan acupoints activated different functional brain areas,and caused activation of different intensities in some areas. 展开更多
关键词 functional magnetic resonance imaging cutaneous acupuncture routine acupuncture Neiguan p C6) Waiguan (SJ 5) Zhigou (SJ 6) Yanglingquan (GB 34) neural regeneration
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Image recognition and empirical application of desert plant species based on convolutional neural network 被引量:2
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作者 LI Jicai SUN Shiding +2 位作者 JIANG Haoran TIAN Yingjie XU Xiaoliang 《Journal of Arid Land》 SCIE CSCD 2022年第12期1440-1455,共16页
In recent years,deep convolution neural network has exhibited excellent performance in computer vision and has a far-reaching impact.Traditional plant taxonomic identification requires high expertise,which is time-con... In recent years,deep convolution neural network has exhibited excellent performance in computer vision and has a far-reaching impact.Traditional plant taxonomic identification requires high expertise,which is time-consuming.Most nature reserves have problems such as incomplete species surveys,inaccurate taxonomic identification,and untimely updating of status data.Simple and accurate recognition of plant images can be achieved by applying convolutional neural network technology to explore the best network model.Taking 24 typical desert plant species that are widely distributed in the nature reserves in Xinjiang Uygur Autonomous Region of China as the research objects,this study established an image database and select the optimal network model for the image recognition of desert plant species to provide decision support for fine management in the nature reserves in Xinjiang,such as species investigation and monitoring,by using deep learning.Since desert plant species were not included in the public dataset,the images used in this study were mainly obtained through field shooting and downloaded from the Plant Photo Bank of China(PPBC).After the sorting process and statistical analysis,a total of 2331 plant images were finally collected(2071 images from field collection and 260 images from the PPBC),including 24 plant species belonging to 14 families and 22 genera.A large number of numerical experiments were also carried out to compare a series of 37 convolutional neural network models with good performance,from different perspectives,to find the optimal network model that is most suitable for the image recognition of desert plant species in Xinjiang.The results revealed 24 models with a recognition Accuracy,of greater than 70.000%.Among which,Residual Network X_8GF(RegNetX_8GF)performs the best,with Accuracy,Precision,Recall,and F1(which refers to the harmonic mean of the Precision and Recall values)values of 78.33%,77.65%,69.55%,and 71.26%,respectively.Considering the demand factors of hardware equipment and inference time,Mobile NetworkV2 achieves the best balance among the Accuracy,the number of parameters and the number of floating-point operations.The number of parameters for Mobile Network V2(MobileNetV2)is 1/16 of RegNetX_8GF,and the number of floating-point operations is 1/24.Our findings can facilitate efficient decision-making for the management of species survey,cataloging,inspection,and monitoring in the nature reserves in Xinjiang,providing a scientific basis for the protection and utilization of natural plant resources. 展开更多
关键词 desert plants image recognition deep learning convolutional neural network Residual Network X_8GF(RegNetX_8GF) Mobile Network v2(MobileNetv2) nature reserves
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