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基于增强T1加权图像构建不同模型鉴别胶质母细胞瘤与单发脑转移瘤

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广东医科大学学报 2024年第3期42卷 266-272页

作者：陈佩仪黄海涛茂名市人民医院核磁共振科广东茂名525000

目的探讨基于增强T1加权图像构建的不同模型鉴别胶质母细胞瘤(GBM)与单发脑转移瘤(SBM)的应用效果。方法227例患者(GBM 120例和SBM 107例)随机分为训练集(n=159)与验证集(n=68)。将增强T1加权图像导入3D-Slicer软件并手动勾画感兴趣区(R... 详细信息

目的探讨基于增强T1加权图像构建的不同模型鉴别胶质母细胞瘤(GBM)与单发脑转移瘤(SBM)的应用效果。方法227例患者(GBM 120例和SBM 107例)随机分为训练集(n=159)与验证集(n=68)。将增强T1加权图像导入3D-Slicer软件并手动勾画感兴趣区(ROI),然后进行影像组学特征提取并使用t检验、递归消除特征法及最小绝对收缩选择算子筛选特征。基于最佳特征,分别运用逻辑回归(LR)、支持向量机(SVM)及随机森林(RF)算法建立模型(影像组学模型、临床模型、临床-影像组学模型),通过绘制受试者工作特征曲线(ROC)及曲线下面积(AUC)delong检验评价各模型鉴别GBM与SBM诊断效能。结果GBM与SBM病灶是否出血坏死及病灶分布情况(幕上或幕下)的比较差异有统计学意义(P0.75)初步获取965个稳定性影像特征,最终筛选得到5个最优影像特征构建模型,影像组学模型和临床-影像组学模型AUC均大于0.8,其中LR模型鉴别效能最优(P<0.05)。决策曲线分析显示在整个阈值概率范围内,影像组学模型和临床-影像组学模型有相当的总体净效益。结论基于增强后T1加权图像构建的影像组学模型和临床-影像组学模型对GBM与SBM具有较高的鉴别诊断效能。

关键词：机器学习影像组学胶质母细胞瘤脑转移瘤列线图

Regional Study on Economical Supporting Capacity of Land Resources in Shandong Province

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Chinese Journal of Population,Resources and Environment 2007年第1期5卷 68-73页

作者： Li Yujiang chen pei＇an College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Taking the land resources of 17 cities in Shandong Province as the basic data, the article studied on the economical supporting capacity of land resources in terms of the effect of land on economy. The author classified 17 cities of Shandong Province into four types according to the economical supporting capacity of land resources by quantitatively estimating the evaluation indices of the total amount of land resources, the potential of urban and other nonagricultural land, and the integrated economical sup- porting capacity of land resources, etc. The author proposes the questions requiring further study at the end of this article.

关键词： land resources economical supporting capacity quantitative estimation Shandong Province

N-doped carbon nanocages： Bifunctional electrocatalysts for the oxygen reduction and evolution reactions

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Nano Research 2018年第4期11卷 1905-1916页

作者： Nan Jia Qiang Weng Yaru Shi Xinyan Shi Xinbing chen pei chen Zhongwei An Yu chen Key Laboratory of Applied Surface and Colloid Chemistry (MOE) School of Materials Science and Engineering Shaanxi NormalUniversity Xi'an 710062 China

Highly effident metal-free, carbon-based, bi-functional electrocatalysts for the oxygen evolution reaction （OER） and oxygen reduction reaction （ORR） have attracted increased attention for use in electrochemical energy conversion systems, owing to their low cost and high activity. In this work, N-doped carbon nanocages （N-CCs） with a porous self-supported architecture and high specific surface area are synthesized by a facile interfacial assembly synthetic route. The materials are comprehensively characterized by scanning electron microscop36 transmission electron microscopy, nitrogen adsorption-desorption experiments, X-ray diffraction, and X-ray photoelectron spectroscopy. Cyclic voltammetry , chronoamperometry, and linear sweep voltammetry demonstrate that the as-prepared N-CC could serve as an effective metal-free electrocatalyst with excellent catalytic activity, long-term operation durability, and excellent methanol tolerance for the ORR in alkaline media. In the presence of 3 mM methanol, the half wave potential of the N-CCs for the ORR is 190 mV; this is more positive than that of the commercial Pt/C electrocatalyst. Meanwhile, the N-CCs also show an OER activity comparable to that of the commercial Ru/C electrocatalyst, revealing their bifunctional property.

关键词： N-doped carbon nanocages bifunctional electrocatalyst oxygen reduction reaction oxygen evolution reaction

Updates on the treatment and outcomes of dual chronic hepatitis C and B virus infection

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World Journal of Gastroenterology 2014年第11期20卷 2955-2961页

作者： Chun-Jen Liu pei-Jer chen Graduate Institute of Clinical Medicine Department of Internal Medicineand Hepatitis Research CenterNational Taiwan University College of Medicine and National Taiwan University Hospital

Dual hepatitis C virus(HCV)/hepatitis B virus(HBV)infection is found in HBV or HCV endemic areas,and in specific populations exhibiting a high risk of parenteral viral *** observations have revealed that HCV/HBV dually infected patients demonstrate a higher risk of liver disease progression compared with HBV or HCV monoinfected *** viral activity responsible for liver disease progression can be determined by examining the viral loads of HCV and HBV and by conducting liver biopsy *** trials have confirmed that the combination therapy of peginterferon alpha-2a or 2b and ribavirin for dual hepatitis patients with HCV dominance appears to be as effective and safe as it is in patients with HCV ***,approximately 60% of dually infected patients with inactive hepatitis B before treatment develop HBV reactivation after the clearance of the *** clinical significance of this HBV reactivation and the strategy to prevent and treat this event should be ***,approximately 30%of dually infected patients lost hepatitis B surface antigen(HBsAg)within 5 years after the start of peginterferonbased therapy,and 40%of them harbored occult HBV *** underlying mechanisms of their accelerating HBsAg seroclearance and the development of occult HBV await further ***,the optimal treatment strategies for dually infected patients who are seropositive for the hepatitis B e antigen must be ***,the advent of new direct-acting antiviral-based anti-HCV therapy may change the optimal therapies for patients with dual hepatitis in the near future,which warrants further clinical trials.

关键词： Dual infection Hepatitis B virus Hepatitis C virus Interferon Pegylated interferon Ribavirin Sustained virological response Hepatitis B surface antigen clearance

STAT3在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制研究

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中南药学 2024年第1期22卷 17-23页

作者：王珏陈佩弦何玲孙逸中国药科大学药学院南京211198

目的研究信号传导及转录激活因子3(STAT3)在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制。方法利用C57BL/6J小鼠双侧海马脑立体定位注射β-淀粉样蛋白建立阿尔茨海默病模型,给予STAT3抑制剂氯硝柳胺,运用动物行为学分析检测、Wes... 详细信息

目的研究信号传导及转录激活因子3(STAT3)在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制。方法利用C57BL/6J小鼠双侧海马脑立体定位注射β-淀粉样蛋白建立阿尔茨海默病模型,给予STAT3抑制剂氯硝柳胺,运用动物行为学分析检测、Western blot分析检测等探究STAT3在认知障碍中的作用及机制。结果行为学实验表明,与模型组小鼠相比,给药组小鼠的焦虑症状、空间探索能力、物体识别能力和学习记忆能力均得到改善;Western blot分析结果表明,给药后小鼠阿尔茨海默病的病理标志物改善,促炎因子表达下调;试剂盒分析结果显示给药组小鼠氧化应激相关指标改善;HE染色结果显示给药组小鼠海马神经元组织形态的改善。结论本研究初步证明了抑制STAT3可减轻神经炎症和氧化应激,从而改善阿尔茨海默病小鼠的认知障碍。

关键词：阿尔茨海默病神经炎症信号传导及转录激活因子3 氯硝柳胺

STAT3信号通路在神经退行性疾病中的研究进展

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中南药学 2024年第1期22卷 6-16页

作者：王珏陈佩弦何玲孙逸中国药科大学药学院南京211198

信号传导及转录激活蛋白3(STAT3)信号通路是机体重要的信号通路,大量体内外研究显示该通路与神经退行性疾病密切相关,其激活引发的神经炎症等在疾病的发生发展中起着重要作用。在阿尔茨海默病和帕金森病中,多项生理生化研究显示STAT3信... 详细信息

信号传导及转录激活蛋白3(STAT3)信号通路是机体重要的信号通路,大量体内外研究显示该通路与神经退行性疾病密切相关,其激活引发的神经炎症等在疾病的发生发展中起着重要作用。在阿尔茨海默病和帕金森病中,多项生理生化研究显示STAT3信号通路在患者体内激活并与多项病理特征存在潜在联系,但其具体作用还存在争议;关于STAT3在其他神经退行性疾病(如血管性痴呆、亨廷顿病、肌萎缩侧索硬化、多发性硬化)的病理生理作用的研究较少,大多集中于药效研究,有待进一步探索发现。本文对STAT3信号通路在神经退行性疾病中的作用进行综述,并列举靶向STAT3药物的最新研究进展,旨在为治疗该类疾病提供有潜力的新靶点。

关键词：信号传导及转录激活蛋白3 神经炎症神经退行性疾病

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水下混凝土浇筑标高自动动态监测技术研究

公路 2024年第6期69卷 116-121页

作者：李雪松姬付全杨钊陈培帅杨睿中交第二航务工程局有限公司武汉市430040 长大桥梁建设施工技术交通行业重点实验室武汉市430040 交通运输行业交通基础设施智能制造技术研发中心武汉市430040

为实现水下混凝土浇筑标高的自动连续测量,基于测锤探头进入泥浆、浮浆及混凝土3种不同介质中的阻力差异,集成电机驱动系统、计米器、压力传感、PLC及测锤探头运动算法,研发水下混凝土浇筑标高自动监测装置。测锤探头实时反馈阻力值,并... 详细信息

为实现水下混凝土浇筑标高的自动连续测量,基于测锤探头进入泥浆、浮浆及混凝土3种不同介质中的阻力差异,集成电机驱动系统、计米器、压力传感、PLC及测锤探头运动算法,研发水下混凝土浇筑标高自动监测装置。测锤探头实时反馈阻力值,并根据设定的压力控制阈值自动控制测锤探头动作;计米器实时显示当前标高监测结果。自动监测装置经过两代产品迭代,分别在武汉双柳大桥项目及广州狮子洋通道工程中应用。标高监测结果与浇筑量换算标高及人工测量结果的对比表明,第一代产品由于动作简单,自动测量模式下易被埋入混凝土,导致结果不准确;而第二代产品提高了智能化程度,测量结果与人工测量结果和浇筑量换算结果接近,且较人工测量结果更稳定。

关键词：桥梁工程水下混凝土浇筑标高自动监测装置智能化技术研究

DC Characteristics of Gamma-ray Irradiated SiGe HBT in Comparison with Si BJT

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Chinese Journal of Aeronautics 2006年第B12期19卷 192-197页

作者： MENG Xiang-ti HUANG Qian WANG Ji lin chen pei-yi TSIEN pei-hsin Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China Institute of Microelectronics Tsinghua University Beijing 100084 China

The changes of DC characteristics of SiGe HBT after being submitted to γ-ray irradiation of 700 krad, 7 000 krad and 10 000 krad were compared to those of Si BJT. Generally speaking, Ib and Ib- Ib0 increase with the doses increasing. For SiGe HBT, with the doses increasing, Ic and Ic-Ic0 as well as the related changes of the current gain （β） will decrease at higher Vbe, while for Si BJT, with the doses increasing, after irradiation, Ib and Ic-Ic0 increase; ,8 and its related changes also decrease with their differences, however, tending to be very small at high doses of 7 000 krad and 10 000 krad. Moreover, given the same doses, the decreases of,a are much larger than SiGe HBT, which shows that SiGe HBT＇s anti-radiation performance proves to be better than Si BJT. Still, in SiGe HBT, some strange phenomena were observed： Ic-Ic0 will increase after the radiation of 7 000 krad in less than 0.65 V and as will ,8 in less than 0.75 V. The mechanism of radiation-induced change in DC characteristies was also discussed.

关键词： γ-ray irradiation SiGe HBT Si BJT DC characteristics

Hyperbranched Polymeric Fluorosurfactants:Synthesis,Surface Activity and Their Application in Firefighting Foams

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Chinese Journal of Polymer Science 2023年第11期41卷 1767-1777,I0009页

作者： Dan-Ling Yang pei-Yao chen Yan Wang Shuang Zhuang Yu chen Hua-Ji Liu Department of Chemistry School of ScienceTianjin UniversityTianjin 300354China Tianjin Fire Research Institute of MEM Tianjin 300381China

Fluorosurfactants are the key ingredients in the formulations of aqueous film-forming foams(AFFFs)for extinguishing flammable liquids,thus developing high-efficient and low-toxic fluorosurfactants is desirable in AFFFs ***,a series of hyperbranched polymeric fluorosu rfactants(HPFs)were successfully synthesized through sequentially modifying hyperbranched polyethylenimine(pei)with the hydrophilic poly(ethylene glycol)(PEG)chains and the hydrophobic C6/C4-based perfluoroalkyl chains,which were verified by FTIR,^(1)H-and^(19)*** surface tensions of all the HPFs in water were measured,and the corresponding physicochemical parameters were *** was found that the surface activities of HPFs could be tuned through adjusting the ratio of PEG to perfluoroalkyl chains,the length of perfluoroalkyl chains,the molecular weight of pei core,but not the PEG chain *** the binary mixture of HPFs with the commercial small molecule fluorosurfactant Capstone^(TM)1157(C1157),a strong synergism led to the elevation of surface activity,which was attributed to the efficient encapsulation of C1157 guests by the compact hyperbranched HPFs as the *** utilization of HPF/C1157 as fluorosurfactant ingredients in AFFF formulations could realize much higher fire-extinguishing efficiency towards flammable oils than the control AFFFs prepa red from the polymeric Capstone^(TM)1460 or the neat C1157.

关键词： Aqueous film-forming foams Firefighting Fluorosurfactant Hyperbranched polymer Surface activity