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Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis
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作者 li xu Huiming xu Changyong Tang 《Neural Regeneration Research》 SCIE CAS 2025年第2期354-365,共12页
Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism rem... Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism remains unknown.Therefore,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets.Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes.These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders.In this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model choices.In addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials. 展开更多
关键词 AQUAPORIN-4 experimental model neuromyelitis optica spectrum disorder PATHOGENESIS
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Effect of Liangxuehuayu Recipe on hemorheology in rats with blood stasis syndrome 被引量:7
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作者 Song-Yi Ning Biao-Ping Jiang +2 位作者 li xu Tai-Hui Fang Mian-Hua Wu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第12期935-938,共4页
Objective:To investigate the effects of Uangxuehuayu Recipe on hemorheology in rats with blood stasis syndrome induced by mutifactor stimuli.Methods:SD rats were divided into control, model,Uangxuehuayu Recipe(high,mi... Objective:To investigate the effects of Uangxuehuayu Recipe on hemorheology in rats with blood stasis syndrome induced by mutifactor stimuli.Methods:SD rats were divided into control, model,Uangxuehuayu Recipe(high,middle and low dose,18,9,4.S g/kg accordingly).Except the control group,blood stasis model was established in the rest groups.The hemorheological parameters were measured and compared.Results:Blood viscosity at high,moderate and low level in rats with blood stasis significantly increased(P【0.05),but blood viscosity at high level and plasma viscosity was significantly decreased in rats induced by some stimuli after Uangxuehuayu Recipe were intra-gastrically administered for I weeks(P【0.01,P【0.05). Conclusions:Uangxuehuayu Recipe is effective in improving hemorheology,and has important application value in the prevention of occurrence and development of ischemic stroke. 展开更多
关键词 Liangxuehuayu RECIPE BLOOD stasis HEMORHEOLOGY SD RATS Platelet AGGREGATION rate Defomation ABILITY AGGREGATION ABILITY BLOOD viscosity
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Novel evidence from Taxus fuana forests for niche-neutral process assembling community 被引量:2
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作者 Tianxiang li li xu +6 位作者 Feng Wang Weijun Zhang Junpeng Duan Xiaolu Shen-Tu Yaobin Song Runguo Zang Ming Dong 《Forest Ecosystems》 SCIE CSCD 2022年第3期378-386,共9页
Background:Understanding the mechanisms underlying community assembly is helpful for conservation and restoration of communities, particularly those that contain rare and endangered species like Taxus fuana, which are... Background:Understanding the mechanisms underlying community assembly is helpful for conservation and restoration of communities, particularly those that contain rare and endangered species like Taxus fuana, which are endemic to the Western Himalayas. The niche (limiting similarity) vs. neutral (randomness) assembly of the T.fuana forest community in Gyirong County, Tibet, China, was investigated. The net relatedness index (NRI) was calculated using a phylogenetic tree. The phylogenetic characteristics of the community and its relationships with environment were analyzed.Results:The value of the mean NRI at the community level was less than-1.96, indicating that the phylogenetic structure was overdispersed;whereas majority of the NRIs at the tree, shrub, and herb layers were within-1.96 to1.96, indicating random dispersion. Environmental factors accounted for 44.38%, 46.52%, 24.04%, and 14.07%of the variation at the community level, tree, shrub, and herb layer, respectively. The phylogenetic structure at the community level and tree layer were significantly influenced by both topographic and soil factors, while shrub and herb layers tended to be affected by a single environmental factor.Conclusions:Community assembly of the T. fuana forest was simultaneously affected by niche and neutral processes, and their variations were closely related to the environment. Neutral process dominated community assembly in the shrub and herb layers. However, the interaction of limiting similarity and randomness played a dominant role at the community level and tree layer;and contributed to maintenance of biodiversity stability. The synergy of multiple environmental factors had a more obvious influence on community assembly than individual environmental factors, especially at the community level. These findings would help to understand the conservation of rare and endangered tree species, such as T. fuana, in the native community;and highlight the importance of random and non-random processes in assembly and biodiversity maintenance of alpine plant communities. 展开更多
关键词 Community assembly Environmental factors Limiting similarity Niche-neutral process Phylogenetic structure RANDOMNESS Rare and endangered species Taxus fuana
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Effects of Xuebijing Combined with Ulinastatin on Coagulation Function of Sepsis Patients 被引量:1
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作者 Yongping ZHANG xuhong TAN +3 位作者 Qin li Hanlin TANG Zaiqun WANG li xu 《Medicinal Plant》 CAS 2019年第3期90-92,共3页
[Objectives] To study the effects of Xuebijing combined with ulinastatin on coagulation function of sepsis patients. [Methods]Fifty six patients conforming to the diagnosis criteria for sepsis and receiving the treatm... [Objectives] To study the effects of Xuebijing combined with ulinastatin on coagulation function of sepsis patients. [Methods]Fifty six patients conforming to the diagnosis criteria for sepsis and receiving the treatment from May 2015 to January 2019 were selected. They were randomly divided into treatment group and control group according to the order of treatment. The two groups were treated according to the International Guidelines for Management of Severe Sepsis and Septic Shock( 2012),in which ulinastatin and Xuebijing were added to the treatment group. Before the treatment and on the seventh day after the treatment,both groups of patients were measured for the activated partial thromboplastin time( APTT),fibrinogen( Fi B),platelet( PLT),and prothrombin time( PT) were measured;the treatment status of the both groups was continuously observed for 7 d,and the mechanical ventilation time,ICU hospitalization time,and 30-day survival rate were recorded. [Results] Both FIB and PLT of the treatment group were significantly increased,and both APTT and PT were significantly shortened.Compared with the control group,the difference was statistically significant( P < 0. 05). The mechanical ventilation time and ICU hospitalization time of the treatment group were significantly shorter than that of the control group,and the 30-day survival rate of the treatment group was significantly higher than that of the control group,and the difference was statistically significant( P < 0. 05). [Conclusions]Xuebijing combined with ulinastatin can improve coagulation disorders of sepsis patients. 展开更多
关键词 SEPSIS XUEBIJING ULINASTATIN COAGULATION FUNCTION
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A Review of Hybrid Cyber Threats Modelling and Detection Using Artificial Intelligence in IIoT 被引量:1
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作者 Yifan liu Shancang li +1 位作者 Xinheng Wang li xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1233-1261,共29页
The Industrial Internet of Things(IIoT)has brought numerous benefits,such as improved efficiency,smart analytics,and increased automation.However,it also exposes connected devices,users,applications,and data generated... The Industrial Internet of Things(IIoT)has brought numerous benefits,such as improved efficiency,smart analytics,and increased automation.However,it also exposes connected devices,users,applications,and data generated to cyber security threats that need to be addressed.This work investigates hybrid cyber threats(HCTs),which are now working on an entirely new level with the increasingly adopted IIoT.This work focuses on emerging methods to model,detect,and defend against hybrid cyber attacks using machine learning(ML)techniques.Specifically,a novel ML-based HCT modelling and analysis framework was proposed,in which L1 regularisation and Random Forest were used to cluster features and analyse the importance and impact of each feature in both individual threats and HCTs.A grey relation analysis-based model was employed to construct the correlation between IIoT components and different threats. 展开更多
关键词 Cyber security Industrial Internet of Things artificial intelligence machine learning algorithms hybrid cyber threats
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基于电磁-热耦合的中压电缆热缩终端异常发热机理及状态监测研究
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作者 唐庆华 方静 +3 位作者 李旭 宋鹏先 李季 于洋 《绝缘材料》 北大核心 2025年第3期141-151,共11页
中压电缆热缩终端常出现局部异常发热现象,该现象会加速电缆绝缘老化,甚至导致电缆绝缘过早失效。为了揭示中压电缆热缩终端异常发热原因,本文基于电磁-热耦合对电缆热缩终端在各种典型故障条件下的电热场进行仿真。结果表明:在电缆长... 中压电缆热缩终端常出现局部异常发热现象,该现象会加速电缆绝缘老化,甚至导致电缆绝缘过早失效。为了揭示中压电缆热缩终端异常发热原因,本文基于电磁-热耦合对电缆热缩终端在各种典型故障条件下的电热场进行仿真。结果表明:在电缆长期运行过程中,当应力控制管发生老化,会导致绝缘局部温升现象,且老化越严重,温升数值越高。此外,当终端外表面因积尘受潮形成污秽且污秽层位于外半导电层断口附近时会形成明显热点,而当污秽层远离断口时,则热点衰退。进一步分析应力控制管内外部受潮下的终端热场分布发现,只有内部受潮时才会引起热点出现。根据所建立的考虑终端内部缺陷热点的热路模型,实施温度反演对热缩终端内部绝缘界面最高温度点进行监测,验证了该方法的有效性。 展开更多
关键词 中压电缆 热缩终端 异常发热 电磁-热耦合 温度反演
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短波中波红外折反射式共口径光学系统设计
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作者 马洪涛 韩冰 +2 位作者 许洪刚 李旭 张明亮 《中国光学(中英文)》 北大核心 2025年第2期359-367,共9页
为了实现高精度、高可靠性的动态场景模拟,设计了一套短波中波多波段折反射式共口径光学系统。该系统结合了反射、折射和共口径光路的优势,该系统分为主光学系统、短波光学系统和中波光学系统,3个系统分别独立设计。通过理论计算得到光... 为了实现高精度、高可靠性的动态场景模拟,设计了一套短波中波多波段折反射式共口径光学系统。该系统结合了反射、折射和共口径光路的优势,该系统分为主光学系统、短波光学系统和中波光学系统,3个系统分别独立设计。通过理论计算得到光学系统的初始结构,再利用光学设计软件对光学参数作进一步细化,最后,按照光瞳匹配原则将各分系统组合在一起,并对系统的成像质量作进一步优化设计。利用调制传递函数(Modulation Transfer Function,MTF)和畸变等定量评价指标,仿真验证了系统设计的合理性。结果显示:所设计的短波光学系统视场角为±0.107°、焦距为2500 mm、入瞳尺寸为300 mm,MTF达到衍射极限,畸变小于0.3%;中波光学系统的视场角为±0.65°、焦距为750 mm、入瞳尺寸为300 mm,MTF接近衍射极限,畸变小于1%。该系统成像质量好、体积小、实用性强,在光电跟瞄和空间探测等领域具有较大应用潜力。 展开更多
关键词 景物模拟器 光学设计 短波中波红外成像 共口径光学系统
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边缘-分割交叉引导的伪装目标检测网络
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作者 陈鹏 李旭 +1 位作者 向道岸 余肖生 《计算机科学与探索》 北大核心 2025年第4期1001-1010,共10页
基于边缘感知的模型是伪装目标检测的主流方法之一,其核心是在早期阶段输出边缘预测,能更好地定位和分割伪装目标。而在伪装目标数据集中,由于伪装目标与背景环境有很高的视觉相似性,对早期的边缘预测质量要求很高,错误的前景预测会导... 基于边缘感知的模型是伪装目标检测的主流方法之一,其核心是在早期阶段输出边缘预测,能更好地定位和分割伪装目标。而在伪装目标数据集中,由于伪装目标与背景环境有很高的视觉相似性,对早期的边缘预测质量要求很高,错误的前景预测会导致分割不完整,甚至缺失目标,进而造成伪装目标分割效果不佳。为了解决这一问题,提出了一种边缘-分割交叉引导网络ECGNet。利用ConvNeXt模型作为骨干网络,通过1×1卷积对特征通道进行统一处理,在多尺度上提取全局上下文信息。设计了一个分割诱导边缘融合模块和一个边缘感知引导完整性聚合模块交叉融合,关注伪装目标的整体结构,不断细化分割特征和边缘特征。通过引导残差通道注意模块利用这些连接和卷积更好地提取低层特征中的结构细节。在CAMO、COD10K以及NC4K数据集上的实验结果表明,ECGNet性能优于其他22个具有代表性的模型,比HitNet在S_(α)、E_(ϕ)、F^(ω)_(β)和M方面的性能平均提升了0.019、0.019、0.018和0.009。 展开更多
关键词 伪装目标检测 上下文信息 交叉细化 边缘感知
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源-荷匹配机制下的水光互补系统中长期与短期嵌套优化调度模型
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作者 黄显峰 黄晗 +3 位作者 鲜于虎成 张艳青 李旭 许昌 《水利水电科技进展》 北大核心 2025年第2期38-45,共8页
针对高比例光伏发电渗透下水光互补系统源-荷同步性显著下降的问题,构建了一种外层长期水量调蓄与内层短期电力互补相耦合的嵌套调度模型。该模型在外层识别光伏出力与负荷曲线特征,而在内层基于源-荷匹配机制,根据水、光、荷特性将输... 针对高比例光伏发电渗透下水光互补系统源-荷同步性显著下降的问题,构建了一种外层长期水量调蓄与内层短期电力互补相耦合的嵌套调度模型。该模型在外层识别光伏出力与负荷曲线特征,而在内层基于源-荷匹配机制,根据水、光、荷特性将输电通道划分为多个目标空间,并采用层内目标分级与层间全局搜索的耦合联动机制,求解输电通道电量配比,得到各目标空间的电量分布情况。澜沧江西藏段水光互补系统实例分析结果表明,构建的模型能够有效引导系统运行工况趋近目标偏好区域,所制订的调度方案能够满足短期弃电、波动风险控制与电力调峰需求,验证了模型的合理性。 展开更多
关键词 水光互补系统 源-荷匹配 输电通道 优化调度模型
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一体化快堆堆内净化用高温浸没泵性能试验研究
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作者 李煦 耿晓 +3 位作者 姚泽文 禹春利 吴鹏 於根芳 《原子能科学技术》 北大核心 2025年第S1期111-119,共9页
在中国原子能科学研究院的一体化快堆项目中,为实现一回路钠不出堆,防止放射性钠泄漏,采用堆内冷阱净化钠中杂质,使一回路的钠在堆容器内部完成净化。为适应堆内冷阱净化需求,需重新研发堆内钠泵送装置。本文设计了适用于堆内冷阱的高... 在中国原子能科学研究院的一体化快堆项目中,为实现一回路钠不出堆,防止放射性钠泄漏,采用堆内冷阱净化钠中杂质,使一回路的钠在堆容器内部完成净化。为适应堆内冷阱净化需求,需重新研发堆内钠泵送装置。本文设计了适用于堆内冷阱的高温浸没泵,浸没泵从钠池中抽钠,通过顶部出口将钠输入堆内冷阱内筒中,为钠在冷阱内的循环净化提供稳定、可调节的动力。针对高温浸没泵样机,开展了模拟堆内钠环境下的性能试验,得到了浸没泵在不同电力条件时的流量-扬程曲线、流量-效率曲线、流量-功率曲线,以及关键部件温度等试验值,并将试验结果与仿真计算结果进行分析比较。结果表明,所研发的浸没泵样机在高温(360℃)钠介质环境、额定工况下,能够满足流量8 m^(3)/h、扬程0.2 MPa的工程需求,同时实际绕组线圈温度低于安全运行温度(450℃),满足设计要求。上述结果为进一步服务堆内净化提供了支持。 展开更多
关键词 一体化快堆 浸没泵 性能试验 仿真计算
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基于CSR规范的油船典型节点疲劳强度影响因素分析
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作者 李旭 张道坤 何凯 《舰船科学技术》 北大核心 2025年第3期72-76,共5页
协调后的CSR规范已经生效9年的时间,在近些年的船舶设计与审图过程中发现了若干疲劳方面的问题。本文选取一型阿芙拉油船对其典型节点位置的疲劳强度问题进行分析讨论,尤其关注之前CSR-OT规范疲劳评估范畴以外的评估节点,例如,底边舱折... 协调后的CSR规范已经生效9年的时间,在近些年的船舶设计与审图过程中发现了若干疲劳方面的问题。本文选取一型阿芙拉油船对其典型节点位置的疲劳强度问题进行分析讨论,尤其关注之前CSR-OT规范疲劳评估范畴以外的评估节点,例如,底边舱折角位置处较难满足规范要求的嵌接肘板趾端、横舱壁水平桁根部和趾端、甲板分段扇形孔等。并就相关位置处疲劳强度的影响因素、规范可能存在的问题、设计标准进行分析讨论,形成若干结论,为未来船舶设计提供参考。 展开更多
关键词 油船 疲劳强度 CSR
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装备自然环境试验数据工程建设方法与实践
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作者 张伦武 周堃 +5 位作者 谭甜甜 王竟成 舒畅 周俊炎 李旭 谢婧 《装备环境工程》 2025年第1期186-195,共10页
简要介绍了装备自然环境试验数据的内涵及其重要性,分析了国外自然环境试验站网、数据资源深层次开发利用、数据共享服务等建设现状。重点从基础设施与服务保障能力、数据治理管控模式等方面,概述了国内装备自然环境试验数据工程建设现... 简要介绍了装备自然环境试验数据的内涵及其重要性,分析了国外自然环境试验站网、数据资源深层次开发利用、数据共享服务等建设现状。重点从基础设施与服务保障能力、数据治理管控模式等方面,概述了国内装备自然环境试验数据工程建设现状与成效,提出了要进一步激活要素价值潜能、创新数据共建共享服务模式、创新数据服务体制机制、加快推进产业数字化等建议。 展开更多
关键词 数据工程 自然环境试验站网 环境适应性 数据治理 共建共享 数字化转型
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Unraveling the relationship between histone methylation and nonalcoholic fatty liver disease
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作者 li xu Yu-Hong Fan +1 位作者 Xiao-Jing Zhang Lan Bai 《World Journal of Hepatology》 2024年第5期703-715,共13页
Non-alcoholic fatty liver disease(NAFLD)poses a significant health challenge in modern societies due to shifts in lifestyle and dietary habits.Its complexity stems from genetic predisposition,environmental influences,... Non-alcoholic fatty liver disease(NAFLD)poses a significant health challenge in modern societies due to shifts in lifestyle and dietary habits.Its complexity stems from genetic predisposition,environmental influences,and metabolic factors.Epigenetic processes govern various cellular functions such as transcription,chromatin structure,and cell division.In NAFLD,these epigenetic tendencies,especially the process of histone methylation,are intricately intertwined with fat accumulation in the liver.Histone methylation is regulated by different enzymes like methyltransferases and demethylases and influences the expression of genes related to adipogenesis.While early-stage NAFLD is reversible,its progression to severe stages becomes almost irreversible.Therefore,early detection and intervention in NAFLD are crucial,and understanding the precise role of histone methylation in the early stages of NAFLD could be vital in halting or potentially reversing the progression of this disease. 展开更多
关键词 Non-alcoholic fatty liver disease MECHANISM Histone methylation METHYLTRANSFERASES Demethytrasferases Epigenetic modification ADIPOGENESIS
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基于JAK/STAT3信号通路探讨SLIT3对高糖诱导的人肾小球足细胞炎症反应的影响
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作者 董杨 陆晨 +3 位作者 黄明芳 李旭 张雪琴 朱国强 《解剖学研究》 CAS 2024年第5期476-482,共7页
目的探讨SLIT3能否调控JAK/STAT3信号通路调控高糖诱导的肾小区足细胞炎症反应。方法将肾小球足细胞MPC-5随机分为L-Glucose+NC siRNA组、L-Glucose+SLIT3组、L-Glucose+SLIT3 siRNA组、H-Glucose+NC siRNA组、H-Glucose+SLIT3组、H-Glu... 目的探讨SLIT3能否调控JAK/STAT3信号通路调控高糖诱导的肾小区足细胞炎症反应。方法将肾小球足细胞MPC-5随机分为L-Glucose+NC siRNA组、L-Glucose+SLIT3组、L-Glucose+SLIT3 siRNA组、H-Glucose+NC siRNA组、H-Glucose+SLIT3组、H-Glucose+SLIT3 siRNA组。流式细胞仪检测细胞凋亡率;ELISA检测细胞中炎症因子水平;蛋白质印迹检测细胞中JAK2、p-JAK2、STAT3、p-STAT3蛋白表达;RT-PCR检测细胞中SLIT3、IL-1β、IL-6、TNF-α相对表达量。结果与Ctrl组相比,SLIT3-siRNA1组(0.67±0.04)、SLIT3-siRNA2组(0.26±0.03)和SLIT3-siRNA3组(0.71±0.08)MPC-5细胞中SLIT3对表达量均明显降低,且SLIT3-siRNA3组变化最显著(P<0.01);与L-Glucose+NC siRNA组相比,L-Glucose+SLIT3组和H-Glucose+NC siRNA组MPC-5细胞凋亡率(分别为11.84%±1.06%、11.88%±1.07%)、细胞中IL-1β(分别为164.69±6.92、155.31±8.62)、IL-6(分别为162.16±5.56、105.35±3.44)、TNF-α(分别为103.31±6.84、128.43±4.82)水平及mRNA相对表达量、细胞中p-JAK2/JAK2(分别为1.74±0.14、3.93±0.17)和p-STAT3/STAT3比值(分别为1.99±0.24、4.43±0.16)明显增加,L-Glucose+SLIT3siRNA组细胞凋亡率(2.73%±0.25%)、细胞中IL-1β(78.09±7.47)、IL-6(46.48±2.63)、TNF-α水平(42.61±3.10)及mRNA相对表达量、细胞中p-JAK2/JAK2(0.16±0.04)和p-STAT3/STAT3(0.20±0.03)比值明显降低(P<0.01);与H-Glucose+NC siRNA组相比,H-Glucose+SLIT3组MPC-5细胞凋亡率(16.24%±1.28%)、细胞中IL-1β(214.09±9.28)、IL-6(205.44±6.80)、TNF-α水平(192.11±4.93)及mRNA相对表达量、细胞中p-JAK2/JAK2(5.00±0.39)和p-STAT3/STAT3比值(5.71±0.33)明显增加,H-Glucose+SLIT3 siRNA组细胞凋亡率(6.25%±0.43%)、细胞中IL-1β(118.60±8.05)、IL-6(74.37±4.91)、TNF-α水平(98.76±4.81)及mRNA相对表达量、细胞中p-JAK2/JAK2(2.99±0.13)和p-STAT3/STAT3(2.05±0.14)比值明显降低(P<0.01)。结论敲减SLIT3可抑制高糖诱导的肾小球足细胞中炎症反应和细胞凋亡,改善足细胞损伤,其作用机制可能比抑制JAK2/STAT3信号通路激活有关。 展开更多
关键词 SLIT3 高糖诱导的肾小球足细胞 JAK2/STAT3信号通路 炎症反应
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融合相似预报方法在陇东南短期强降水预报中的应用 被引量:1
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作者 黄晓远 李旭 +2 位作者 杜梦莹 叶培龙 李艳 《高原气象》 北大核心 2025年第1期214-223,共10页
基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进... 基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进行了检验。结果表明:(1)融合相似预报方法的TS评分处于4.5%~9.1%之间,与ECMWF模式预报结果相比表现出一定的优势。随着预报时效的增长,强降水预报的TS评分呈现减小的趋势,其在08:00(北京时,下同)起报的TS评分相对较高。(2)相比于单独使用逐步过滤相似预报,融合相似预报方法的准确性有所提升,并能在一定程度上降低空报率。其中08:00起报和20:00起报的TS评分提高了1.31%和0.63%,而FAR同时下降了2.39%和1.25%。 展开更多
关键词 强降水 短期预报 相似预报 逐步过滤相似 自组织映射(SOM)
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Application and Satisfaction Analysis of Humanized Quality Nursing Intervention in the Care of Patients with Critical Respiratory Failure
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作者 li xu 《Journal of Clinical and Nursing Research》 2024年第5期200-205,共6页
Objective:To implement humanized quality care in critical respiratory failure nursing,observe the effect,and analyze the satisfaction.Methods:80 patients with severe respiratory failure were divided into 40 cases per ... Objective:To implement humanized quality care in critical respiratory failure nursing,observe the effect,and analyze the satisfaction.Methods:80 patients with severe respiratory failure were divided into 40 cases per group(admitted from February 2022 to December 2023)by double-blind method,the control group performed routine care,and the observation group was given humanized quality care.Results:After the nursing care,two respiratory function indexes of the observation group were lower than those of the control group,and two pulmonary function indexes were higher than those of the control group(P<0.05);regarding the complication situation,the incidence rate of the observation group was lower(P<0.05);regarding the nursing care satisfaction situation,the observation group had a higher level of total satisfaction(P<0.05).Conclusion:The application of a humanized quality nursing intervention model in the care of critical respiratory failure can actively improve patients’respiratory status and lung function,reduce complications,and satisfy patients. 展开更多
关键词 Critical respiratory failure Humanized quality nursing Nursing satisfaction
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AC+Li(NiCoMn)O2/Li4Ti5O12+MWCNTs混合型电容器 被引量:1
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作者 陈玮 孙晓刚 +5 位作者 胡浩 王杰 李旭 梁国东 黄雅盼 魏成成 《材料工程》 EI CAS CSCD 北大核心 2020年第1期128-135,共8页
以钛酸锂(Li 4Ti 5O 12)/多壁碳纳米管(MWCNTs)复合材料为负极、活性炭(AC)/镍钴锰酸锂(Li(NiCoMn)O 2)复合材料为正极,组装成混合型电容器并研究其电化学性能。利用扫描电子显微镜(SEM),透射电子显微镜(TEM),X射线衍射仪(XRD),拉曼光谱... 以钛酸锂(Li 4Ti 5O 12)/多壁碳纳米管(MWCNTs)复合材料为负极、活性炭(AC)/镍钴锰酸锂(Li(NiCoMn)O 2)复合材料为正极,组装成混合型电容器并研究其电化学性能。利用扫描电子显微镜(SEM),透射电子显微镜(TEM),X射线衍射仪(XRD),拉曼光谱仪(Raman),热重分析仪(TGA)对电极材料进行分析,通过恒流充放电(GCD)和交流阻抗谱(EIS)研究混合型电容器的电化学性能。结果表明:掺杂适量MWCNTs和镍钴锰酸锂可提高电容器的电化学性能。当MWCNTs质量分数为5%时,在电流密度为0.1 A/g下恒流充放电时比容量达161.5 mAh/g。在0.1~1 A/g时,最大功率密度和最大能量密度分别为993.2 W/kg和52.2 Wh/kg。5000周次恒流充放电循环后,容量保持率在92.2%左右,库仑效率仍有99.1%,展现出较高的能量密度和功率密度,并具有优异的循环性能。 展开更多
关键词 多壁碳纳米管 镍钴锰酸锂 钛酸锂 活性炭 混合电容
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肝癌组织中LIV-1基因mRNA的表达及意义 被引量:1
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作者 吴文婧 韩少山 +2 位作者 陈葳 李旭 赵乐 《山西医科大学学报》 CAS 2019年第6期715-718,共4页
目的探讨锌转运体LIV-1基因mRNA在肝癌组织中的表达及意义。方法对TCGA数据库中肝癌数据集的LIV-1基因的表达进行分析,采用逆转录PCR方法检测23例肝癌患者癌组织及其癌旁组织的LIV-1基因的mRNA表达水平进行验证。利用Kaplan Meier Plot... 目的探讨锌转运体LIV-1基因mRNA在肝癌组织中的表达及意义。方法对TCGA数据库中肝癌数据集的LIV-1基因的表达进行分析,采用逆转录PCR方法检测23例肝癌患者癌组织及其癌旁组织的LIV-1基因的mRNA表达水平进行验证。利用Kaplan Meier Plotter数据(http://kmplot.com/analysis/)中的肝癌数据集进行在线生存分析。通过生物信息学方法分析LIV-1基因启动子区的甲基化水平。结果TCGA数据库分析结果显示LIV-1 mRNA在肝癌组织中的表达显著高于正常肝脏组织(P<0.01),组织样本验证了生物信息学分析结果。相对于LIV-1低表达的肝癌患者,高表达LIV-1的肝癌患者的预后差(P<0.001)。相对于正常肝组织,LIV-1基因启动子区在肝癌组织中呈低甲基化(P<0.01)。结论异常高表达的LIV-1基因可能参与了肝癌的进展,是一种预后不良的因素。LIV-1基因启动子区低甲基化可能导致了其异常高表达。 展开更多
关键词 肝细胞癌 LIV-1 TCGA数据库 预后 甲基化
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Ni、Co、Al掺杂尖晶石LiMn_(2)O_(4)的第一性原理计算 被引量:2
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作者 李旭 王建川 杜勇 《粉末冶金材料科学与工程》 2021年第5期387-395,共9页
针对分别掺杂Ni、Co、Al的尖晶石LiMn_(2)O_(4),采用基于密度泛函理论的第一性原理计算方法,分析反铁磁层和铁磁层沿[001]方向交替排列的磁性构型的合理性。结果表明,此磁结构下表现出Mn^(3+)/Mn^(4+)沿[001]方向交替排列的价态分布。Ni... 针对分别掺杂Ni、Co、Al的尖晶石LiMn_(2)O_(4),采用基于密度泛函理论的第一性原理计算方法,分析反铁磁层和铁磁层沿[001]方向交替排列的磁性构型的合理性。结果表明,此磁结构下表现出Mn^(3+)/Mn^(4+)沿[001]方向交替排列的价态分布。Ni、Co、Al三种掺杂原子都倾向于替换Mn^(3+)层上的Mn,占据16d位后价态表现为Ni^(2+)、Co^(3+)和Al^(3+)。Al与Ni掺杂均能抑制掺杂点位的Jahn-Teller畸变,且Ni掺杂后其最近邻的Mn^(3+)被氧化为Mn^(3+),使结构更稳定,而Co掺杂可能导致更严重的Jahn-Teller畸变。Al^(3+)和Co^(3+)可显著降低Li离子的两条路径扩散能垒,Ni^(2+)在Mn^(3+)的协同作用下可进一步降低低能垒路径的能垒。 展开更多
关键词 正极材料 LiMn_(2)O_(4)掺杂 磁性结构 扩散
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Mutant Selection Windows of Azalomycin F5a in Combination with Vitamin K3 against Methicillin-Resistant Staphylococcus aureus
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作者 xuejie xu xuejiao Wu +2 位作者 Ganjun Yuan li xu Yimin Wang 《Journal of Biosciences and Medicines》 2016年第12期162-174,共13页
Azalomycin F<sub>5a</sub>, a 36-membered macrocyclic lactone isolated from several streptomyces strains, presented remarkable anti-methicillin-resistant Staphylococcus aureus (MRSA) activities. To improve ... Azalomycin F<sub>5a</sub>, a 36-membered macrocyclic lactone isolated from several streptomyces strains, presented remarkable anti-methicillin-resistant Staphylococcus aureus (MRSA) activities. To improve its anti-MRSA potential and to evaluate the probability of MRSA resistant to it before development, the anti-MRSA activities of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> were first evaluated using checkerboard assay. Then the minimal concentration inhibiting colony formation by 99% (MIC<sub>99</sub>) and mutant prevention concentration (MPC) of azalomycin F<sub>5a</sub> alone and in combination with vitamin K<sub>3</sub> against MRSA were determined using agar plates with linear antimicrobial concentration decrease. The fractional inhibitory concentration indexes (FICIs) of 0.25 - 0.50 showed the synergistic activity of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub>. The mutant selection windows (MSWs, MIC<sub>99</sub>-MPC) of azalomycin F<sub>5a</sub> alone against MRSA tested were 2.07 - 6.40 μg/mL, and the MPCs of azalomycin F<sub>5a</sub> in combination with vitamin K<sub>3</sub> against MRSA tested were 1.60 - 3.20 μg/mL. These indicated that the MPCs of azalomycin F<sub>5a</sub> in combination could drop down to below its MIC<sub>99</sub> alone. According to the hypothesis of MSW, the narrower MSWs of azalomycin F<sub>5a </sub>alone, even closed MSWs in combination with vitamin K<sub>3</sub>, together with their synergistic anti-MRSA activities, indicated that azalomycin F<sub>5a </sub>had a good potential to develop as a new antimicrobial agent. 展开更多
关键词 MRSA Azalomycin F5a Mutant Selection Windows COMBINATION Antibiotic Resistance
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