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羟基积雪草苷通过激活Nrf2-HO-1通路发挥抗衰老及皮肤修复作用
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作者 王丹 俞舜 +3 位作者 王玉英 李京玲 刘晨阳 吕国忠 《日用化学工业(中英文)》 CAS 北大核心 2024年第6期683-690,共8页
考察羟基积雪草苷(MA)对D-半乳糖诱导的皮肤衰老小鼠的抗衰老及皮肤修复作用。将小鼠分为6组(n=12):正常组(N)、模型组(M)、低、中、高剂量MA组(L-MA,M-MA,H-MA)和高剂量MA+Nrf2抑制剂ML385组(H-MA+ML385)。分别检测了各组小鼠的体重、... 考察羟基积雪草苷(MA)对D-半乳糖诱导的皮肤衰老小鼠的抗衰老及皮肤修复作用。将小鼠分为6组(n=12):正常组(N)、模型组(M)、低、中、高剂量MA组(L-MA,M-MA,H-MA)和高剂量MA+Nrf2抑制剂ML385组(H-MA+ML385)。分别检测了各组小鼠的体重、皮肤含水量、皮肤组织中的抗氧化指标(SOD、CAT、GSH-Px和MDA)、HYP和HA水平。采用HE染色评价了小鼠皮肤组织结构。通过RT-qPCR检测了小鼠皮肤组织中MMP-1、MMP-3、Nrf2、Keap1和HO-1的转录水平。通过Western blotting检测了小鼠皮肤组织中Nrf2、Keap1和HO-1的蛋白表达水平。结果显示,与M组比较,L-MA组、M-MA组和H-MA组小鼠皮肤含水量升高,表皮和真皮厚度增加,皮肤结构明显改善,SOD、CAT和GSH-Px水平升高,MDA水平降低,HYP和HA水平升高,MMP-1和MMP-3 mRNA相对表达量降低,Nrf2和HO-1的mRNA和蛋白相对表达量升高,Keap1 mRNA和蛋白相对表达量降低(P<0.05)。ML385部分减弱了MA对Nrf2-HO-1通路的激活效果,并减弱了MA的抗衰老和皮肤修复作用(P<0.05)。本研究表明,MA具有良好的抗衰老和皮肤修复作用,其机制与激活Nrf2-HO-1通路有关。 展开更多
关键词 羟基积雪草苷 抗衰老 皮肤修复 抗氧化 Nrf2-HO-1通路
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长白山垂直带森林叶片-凋落物-土壤连续体有机碳动态——基于稳定性碳同位素分析 被引量:28
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作者 司高月 李晓玉 +5 位作者 程淑兰 方华军 于贵瑞 耿静 何舜 于光夏 《生态学报》 CAS CSCD 北大核心 2017年第16期5285-5293,共9页
稳定性碳同位素自然丰度(δ^(13)C)记录着生态系统碳循环过程的关键信息,常被用于评价全球变化情景下陆地生态系统碳的动态。以长白山北坡垂直带4种典型森林生态系统为研究对象,测定乔木建群种叶片、凋落物以及不同深度土壤有机碳(SOC)... 稳定性碳同位素自然丰度(δ^(13)C)记录着生态系统碳循环过程的关键信息,常被用于评价全球变化情景下陆地生态系统碳的动态。以长白山北坡垂直带4种典型森林生态系统为研究对象,测定乔木建群种叶片、凋落物以及不同深度土壤有机碳(SOC)含量和δ^(13)C值,探讨植物叶片-凋落物-土壤连续体碳含量、δ^(13)C丰度的分布格局及其生态学暗示。研究结果表明:植物叶片碳含量随海拔高度的增加呈现抛物线型变化,且阔叶树叶片碳含量显著低于针叶树,体现气候要素和植被功能型的支配作用,并且暗示针叶树种潜在的碳蓄积能力更强。此外,植物叶片δ^(13)C随海拔高度升高而降低,表明高海拔植物叶片水分利用效率较低,即固碳耗水成本更高。凋落物碳含量随海拔增加逐渐下降,而矿质表层土壤则表现为阔叶红松林、岳桦林显著高于暗针叶林,体现了植被类型和土壤质地的共同支配作用。总体上,岳桦林SOC周转最快,其次是暗针叶林,位于基带的阔叶红松林最慢。可见,小尺度上气候因子并不是温带森林地下碳循环的主导因素,植被功能型和土壤属性对SOC周转与稳定的影响更大。在探讨环境因子对陆地生态系统碳循环和碳平衡的影响时需要考虑研究尺度,不同的研究尺度影响SOC周转的驱动因子并不相同。研究方法方面,基于log SOC和δ^(13)C的SOM周转模型能够很好地概括不同生态系统类型下SOM周转的相对快慢,可用来评价SOC动态对全球变化的响应。 展开更多
关键词 13C自然丰度 叶片-凋落物-土壤连续体 水分利用效率 土壤碳周转 山地垂直带
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迁移蜂群优化算法及其在无功优化中的应用 被引量:18
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作者 徐茂鑫 张孝顺 余涛 《自动化学报》 EI CSCD 北大核心 2017年第1期83-93,共11页
提出了一种全新的迁移蜂群优化算法,并应用到电力系统无功优化问题.利用Q学习的试错与奖励机制构造蜂群的学习模式,并采用强化学习的行为迁移技术实现蜂群的迁移学习.为解决算法求解多变量优化问题遇到的维数灾难,提出了状态–组合动作... 提出了一种全新的迁移蜂群优化算法,并应用到电力系统无功优化问题.利用Q学习的试错与奖励机制构造蜂群的学习模式,并采用强化学习的行为迁移技术实现蜂群的迁移学习.为解决算法求解多变量优化问题遇到的维数灾难,提出了状态–组合动作链的方式将状态–动作空间分解成若干低维空间,明显降低算法的计算难度.仿真结果表明:本文所提算法可以保证最优解质量的同时,寻优速度能提高到传统启发式智能算法的4~67倍左右,非常适用于大规模复杂系统非线性规划问题的快速求解. 展开更多
关键词 迁移蜂群优化 强化学习 行为迁移 无功优化
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用于星载激光通信终端的绝对式光电角度编码器 被引量:13
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作者 韩旭东 徐新行 +1 位作者 刘长顺 于思源 《光学精密工程》 EI CAS CSCD 北大核心 2016年第10期2424-2431,共8页
针对星上激光通信终端二维转台的精确控制,设计了实时测量转台旋转角度的专用型光电角度编码器。根据星载激光通信终端所需测角系统的设计指标,分别对光电角度编码器的码盘、指示光栅及光电信号的提取方法进行了设计和选择。其中,格林... 针对星上激光通信终端二维转台的精确控制,设计了实时测量转台旋转角度的专用型光电角度编码器。根据星载激光通信终端所需测角系统的设计指标,分别对光电角度编码器的码盘、指示光栅及光电信号的提取方法进行了设计和选择。其中,格林二进制绝对式编码结合高质量的电子学细分,实现了编码器24位的绝对角度测量;四象限矩阵编码方式有效地减小了码盘的径向尺寸;分体读数头式指示光栅较整周玻璃盘大幅度压缩了体积和重量。在室温条件下对安装在星载激光通信终端上的光电角度编码器进行了测角精度检测。结果表明:该测角系统的角度测量精度约为0.7″(优于1.0″)。激光通信终端设备的在轨稳定运行及捕获、跟踪和通信功能的正常发挥,进一步验证了所设计的光电角度编码器测角精度高、抗辐射能力强、工作可靠性高,满足星载激光通信终端设备的应用要求。 展开更多
关键词 激光通信 光电角度编码器 绝对式角度编码器 角度测量 测量精度
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鳗鳅与泥鳅营养成分分析 被引量:9
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作者 郭霄旭 姜启兴 +3 位作者 陈晓东 许艳顺 于沛沛 夏文水 《轻工学报》 CAS 2017年第1期13-20,共8页
对鳗鳅和泥鳅营养成分进行比较分析,结果表明:1)与肌肉相比,鳗鳅和泥鳅皮中水分含量显著降低(-13.03%,P<0.05;-10.30%,P<0.05),但蛋白含量明显增加(+54.22%,P<0.05;+9.60%,P<0.05),且两种鳅类之间差异显著(P<0.05).2)鳗... 对鳗鳅和泥鳅营养成分进行比较分析,结果表明:1)与肌肉相比,鳗鳅和泥鳅皮中水分含量显著降低(-13.03%,P<0.05;-10.30%,P<0.05),但蛋白含量明显增加(+54.22%,P<0.05;+9.60%,P<0.05),且两种鳅类之间差异显著(P<0.05).2)鳗鳅和泥鳅皮中胶原蛋白含量显著高于肌肉,其均值分别为61.76 mg/g和5.75 mg/g.3)两种鳅类氨基酸组成无明显差异.鳗鳅和泥鳅肌肉中第一限制性氨基酸均为缬氨酸,而皮中第一限制性氨基酸分别为苏氨酸和蛋氨酸+胱氨酸.4)鳗鳅和泥鳅肌肉中的脂肪含量显著高于皮中脂肪含量(P<0.05),且两种鳅类之间差异显著(P<0.05).5)鳗鳅和泥鳅肌肉中多不饱和脂肪酸,相对含量均显著高于皮中脂肪含量.6)鳗鳅和泥鳅肌肉中矿质含量最高的是K,分别达到2 687.36 mg/kg和1 750.49 mg/kg,而鳗鳅和泥鳅皮则富含Ca,分别高达4 091.83 mg/kg和5 948.43 mg/kg. 展开更多
关键词 鳗鳅 泥鳅 营养成分
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马克思现代性思想及其对中国式现代化建设的启示
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作者 吴顺宇 《哈尔滨学院学报》 2024年第3期9-13,共5页
西方的理性主义为马克思现代性思想的形成奠定了基础,马克思对国家与市民社会关系的深入剖析成为了他超越黑格尔历史哲学的重要环节,他对德国历史哲学的批判、对国民经济学的批判以及对近代形而上学的批判共同构建起了马克思现代性思想... 西方的理性主义为马克思现代性思想的形成奠定了基础,马克思对国家与市民社会关系的深入剖析成为了他超越黑格尔历史哲学的重要环节,他对德国历史哲学的批判、对国民经济学的批判以及对近代形而上学的批判共同构建起了马克思现代性思想的具体框架。在中国式现代化建设的理论构建中,马克思现代性思想起到了至关重要的作用,提供了丰富的精神动力。中国式现代化建设将先进文化、中国精神、民族团结融入进去,展现出与西方现代化建设截然不同的中国特色现代化道路。 展开更多
关键词 理性主义 市民社会 中国式现代化 中国特色现代化道路
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生物编带填料对生物反应器运行效果的研究
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作者 黄青飞 李东 周凯 《供水技术》 2023年第5期11-16,共6页
生物负载量是影响生物接触氧化反应器污染物去除的重要因素。本文以工程实践中常用的悬挂式填料为研究对象,考察了不同悬挂式生物填料的生物负载量,并选取生物编带填料为试验对象,分析该生物填料对生物反应器处理生活污水的运行效果。... 生物负载量是影响生物接触氧化反应器污染物去除的重要因素。本文以工程实践中常用的悬挂式填料为研究对象,考察了不同悬挂式生物填料的生物负载量,并选取生物编带填料为试验对象,分析该生物填料对生物反应器处理生活污水的运行效果。结果表明:仿水草填料、螺旋填料、生物编带直线填料、生物编带毛圈填料单位质量填料生物负载量分别为0.30、0.40、0.58、0.40 g/g,单位长度填料生物负载量分别为0.73、11.34、12.64、14.86 g/m。当生物编带直线填料填充率为33%时,生物反应器对COD_(Cr)、TN、NH_(4)^(+)-N的平均去除率分别为73.2%、41.09%、90.16%,达到DB34/3527-2019《农村生活污水处理设施水污染物排放标准》的一级A标准,单位体积生物膜量为2 136.16 g/m^(3),镜检发现填料生物膜上生物相对丰富,先后出现了以细菌为食的原生动物到后生动物过渡的完整生物链。 展开更多
关键词 生物负载量 生物接触氧化 生物编带填料 填充率
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冷轧带钢板形调控虚拟系统及其应用 被引量:4
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作者 杨利坡 张永顺 +2 位作者 于华鑫 李荣民 袁文越 《塑性工程学报》 CAS CSCD 北大核心 2017年第5期82-88,共7页
基于板形测控数学模型和虚拟仪器技术,研制了一种新型的冷轧带钢板形测控系统。首先利用板形仪获得高灵敏度的原始信号,然后根据实际工况计算各种工艺误差,在获得高精度有效板形信号的同时对其进行模式分解和板形调控,观察轧制前后的板... 基于板形测控数学模型和虚拟仪器技术,研制了一种新型的冷轧带钢板形测控系统。首先利用板形仪获得高灵敏度的原始信号,然后根据实际工况计算各种工艺误差,在获得高精度有效板形信号的同时对其进行模式分解和板形调控,观察轧制前后的板形调控效果;其次利用虚拟仪器软件和OPC技术组建虚拟平台,降低硬件风险和设备费用,减少通讯环节和闭环周期,便于组态和调试。工业实例表明,新系统安装方便,易于操作,适应恶劣工况,能够满足在线板形调控要求。 展开更多
关键词 冷轧带钢 板形调控 虚拟仪器 板形检测 闭环控制
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探讨细胞学在原发性肺癌诊断中的作用 被引量:1
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作者 丁顺 余茂武 《中外医学研究》 2016年第28期60-62,共3页
目的:探讨细胞学检测在原发性肺癌诊断中的意义。方法:对收集到的活检、穿刺组织或术后大体标本病理确诊的原发性肺癌的230例患者的痰液、纤维支气管镜刷检涂片、肺泡灌洗液、穿刺涂片、胸水细胞涂片进行回顾性分析。结果:纤维支气管镜... 目的:探讨细胞学检测在原发性肺癌诊断中的意义。方法:对收集到的活检、穿刺组织或术后大体标本病理确诊的原发性肺癌的230例患者的痰液、纤维支气管镜刷检涂片、肺泡灌洗液、穿刺涂片、胸水细胞涂片进行回顾性分析。结果:纤维支气管镜刷检敏感度为87.08%;痰液涂片敏感度为29.03%;肺泡灌洗液细胞涂片敏感度为53.57%;穿刺涂片敏感度为92.31%;胸水细胞涂片敏感度为58.33%,细胞学诊断总敏感度为90.43%。结论:细胞学能协同组织病理提高肺癌检出率,具有重要意义。 展开更多
关键词 纤维支气管镜 细胞学检测 肺癌 胸水
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响应面优化黄酒糟二次发酵利用 被引量:1
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作者 徐建芬 武顺 +3 位作者 俞剑燊 胡健 张凤杰 朱小芳 《酿酒科技》 2017年第10期115-118,共4页
黄酒酒糟是黄酒生产得到的副产物,经过第一次发酵后得到。发酵后的酒糟中蛋白质含量高达26.7%、淀粉含量高达29.96%,为使酒糟得到进一步的利用,本实验将甜酒糟进行二次发酵处理并进行优化,经过优化后得到风味物质提高效果优异,当加水量... 黄酒酒糟是黄酒生产得到的副产物,经过第一次发酵后得到。发酵后的酒糟中蛋白质含量高达26.7%、淀粉含量高达29.96%,为使酒糟得到进一步的利用,本实验将甜酒糟进行二次发酵处理并进行优化,经过优化后得到风味物质提高效果优异,当加水量为65 m L、加酶量为1%、加菌量为10%时,发酵得到风味物质最多,为3220.14 mg/L。 展开更多
关键词 黄酒糟 淀粉 蛋白质
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中意塞三国在2018女排世锦赛中球队进攻实力的分析
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作者 胡顺宇 彭峰林 +2 位作者 陈化冰 李振 刘平 《当代体育科技》 2020年第14期246-249,共4页
2018年女排世锦赛中塞尔维亚获得冠军,意大利获得亚军,中国取得了季军。塞尔维亚和意大利国家女排都是世界一流的女排队伍,是中国女排在排球比赛中较大的竞争对手。对3个国家女排队伍的进攻实力,进行由点到面的对比分析,探索出3个国家... 2018年女排世锦赛中塞尔维亚获得冠军,意大利获得亚军,中国取得了季军。塞尔维亚和意大利国家女排都是世界一流的女排队伍,是中国女排在排球比赛中较大的竞争对手。对3个国家女排队伍的进攻实力,进行由点到面的对比分析,探索出3个国家女排队伍在进攻方面存在的优劣势。结果表明:在本次比赛中,中国女排与其他2个国家在整体扣球、拦网、发球实力方面无明显差距,但是在接应位置上中国女排的扣球实力和其他2个国家还是有差距的;中国女排在主攻和接应位置的进攻强点较少;在拦网实力方面,中国女排闫妮拦网较好,意大利女排在身高不占优势的情况下依然有很好的拦网实力;在发球实力方面,中国女排队员的发球实力参差不齐。根据研究出的结果,提出相应合理化建议与对策,以便中国女排能更有针对性地提高进攻战术,同时为今后中国女排的比赛提供有益参考。 展开更多
关键词 女排世锦赛 中国女排 意大利女排 塞尔维亚女排 进攻实力
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应用驾驶员在环平台非独立后悬架特性分析
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作者 介石磊 孙玉凤 方月 《机械设计与制造》 北大核心 2018年第10期202-206,共5页
悬架对矿用自卸车具有举足轻重作用,其特性直接影响整车性能。由于整车结构特殊性,后悬大多数采用非独立悬架,主要有A型架-横拉杆式和四连杆式。针对两种悬架特点,基于MapleSim建立分析模型,对悬架刚体运动学和弹性运动学性能(K&C特... 悬架对矿用自卸车具有举足轻重作用,其特性直接影响整车性能。由于整车结构特殊性,后悬大多数采用非独立悬架,主要有A型架-横拉杆式和四连杆式。针对两种悬架特点,基于MapleSim建立分析模型,对悬架刚体运动学和弹性运动学性能(K&C特性)进行分析;基于驾驶员在环仿真平台对整车进行闭环操纵稳定性试验对比分析。结果可知:C特性指标数值非常小;两种非独立后悬架在不同K特性指标上发挥优势;平行轮跳时,四连杆式悬架运动学性能在侧向位移变化上优于A型架-横拉杆式悬架,纵向位移变化相差不大;反向轮跳时,A型架-横拉杆式悬架在后桥侧向位移和纵向位移两个指标上变化优于四连杆式,而在后桥侧倾转向角指标上则劣于四连杆式;A型架-横拉杆式悬架应用于整车后表现出较好稳态回转特性,不足转向度高;四连杆式悬架应用于整车后瞬态响应速度快,横摆角速度稳态增益较小。 展开更多
关键词 非独立悬架 四连杆式 A型架-横拉杆式 K&C特性 操纵稳定性
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一种虚拟化深度包检测部署机制
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作者 汪学舜 余少华 戴锦友 《计算机科学》 CSCD 北大核心 2017年第8期90-94,共5页
网络功能虚拟化转变了网络架构和网络业务的部署。在网络功能虚拟化架构中,实现虚拟化深度包检测只需在传输路径上进行一次扫描,但高效部署深度包检测功能引擎成为难题。将深度包检测功能部署问题形式化为线性规划问题以满足约束条件,... 网络功能虚拟化转变了网络架构和网络业务的部署。在网络功能虚拟化架构中,实现虚拟化深度包检测只需在传输路径上进行一次扫描,但高效部署深度包检测功能引擎成为难题。将深度包检测功能部署问题形式化为线性规划问题以满足约束条件,并提出一种基于代价最小的贪婪算法和优化的贪婪算法来解决深度包检测功能部署问题。该算法对部署代价和网络资源代价进行折衷,实现了最小化的部署代价。实验结果表明,所提算法能够实现深度包检测功能部署并取得近似最优解。 展开更多
关键词 深度包检测 部署 网络功能虚拟化 最小代价优化
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Bird species composition and conservation challenges in the Gaoligong Mountains, one of the most diverse bird areas in the world 被引量:1
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作者 Fei Wu Jian-yun Gao +13 位作者 Dao Yan Le Yang Lu-Ming Liu shun-yu Yao Chang-Sheng Zuo Jun Sun Ge Gao Jian-Yong Su Li Luo Ying-Chun Li Ming Liu yuan-Fang Hu Ming Wei Xiao-Jun Yang 《Zoological Research(Diversity and Conservation)》 2024年第1期20-50,共31页
The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird su... The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird surveys conducted in the GLGM between 2010 and 2022.We found that the GLGM harbors tremendous bird diversity,with a total of 796 documented bird species in the region.Nearly a quarter(23.0%)of these species are listed as state key protected species or as Chinese and global threatened species.Analysis of species richness at the county level showed a decreasing trend with increasing latitude,with the greatest diversity in Yingjiang(661 species).Observations indicated that the GLGM belongs to the Oriental realm,primarily composed of bird species from southern and southwestern China.The GLGM plays an important role in avian conservation by sheltering exceptional bird diversity,providing corridors and flyways for bird migration and dispersal,and mitigating the effects of climate change.In response to the conservation needs of birds and other wildlife,the Chinese government has established numerous protected areas within the GLGM.Despite these efforts,avian conservation still faces considerable challenges in the GLGM due to limitations in the protected area network,transboundary nature of the regions,and existing gaps in monitoring and research. 展开更多
关键词 BIRDS Gaoligong Mountains Zoogeographic region Conservation challenge
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Biological Function and Mechanism of Long Noncoding RNAs Nuclear-Enriched Abundant Transcript I in Development of Cervical Cancer 被引量:5
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作者 Hui-Ling Wang shun-yu Hou +3 位作者 Hai-Bo Li Jian-Ping Qiu Le Bo Cai-Ping Mao 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第17期2063-2070,共8页
Background: Accumulating documents have demonstrated that long noncoding RNAs (lncRNAs) play critical roles in tumorigenesis. As an lncRNA, nuclear-enriched abundant transcript 1 (NEAT1) has been identified to be... Background: Accumulating documents have demonstrated that long noncoding RNAs (lncRNAs) play critical roles in tumorigenesis. As an lncRNA, nuclear-enriched abundant transcript 1 (NEAT1) has been identified to be involved in the progression of many types of cancers. However, the biological function of NE.4T1 in cervical cancer is not fully investigated. The aim of this study was to disclose the specific biological function of lncRNA NEATI in cervical cancer progression. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to identify the expression of lncRNA NE,4 T1 in the cervical cancer tissues and cell lines. All cervical cancer samples used in this study were collected from the Affiliated Suzhou Hospital of Nanjing Medical University between September 2012 and September 2017. The correlation between NE,4T1 expression and the overall survival rate of cervical cancer patients was analyzed by Kaplan-Meier analysis. The effects of NEAT1 knockdown or overexpression on cell proliferation were tested by performing MTT assays and colony formation assays. Transwell assays were conducted to detect the migratory ability of cervical cancer cells, in which NEAT1 was silenced or overexpressed. Western blotting was utilized to validate whether NEAT1 promotes cervical cancer progression through activating PI3K-Akt signaling pathway. Results: High expression of NE,4T1 predicted poor prognosis of cervical cancer patients (χ^2= 0.735, P = 0.005). Knockdown of NE,4T1 decreased the number of colonies in CaSki cell from 136.667 ± 13.503 to 71.667 ± 7.506 (t = -18.76, P = 0.003) and decreased the number of colonies in HeLa cell from 128.667 ± 13.317 to 65.667 ± 7.024 (t = -5.54, P = 0.031). However, overexpression of NEA T1 increased the number of colonies in SiHa cell from 84.667 ± 12.014 to 150.667 ± 18.037 (t = 7.27, P = 0.018). Knockdown of NEAT1 decreased the migratory number of CaSki cell from 100.333 ± 9.866 to 58.333 ± 5.859 (t = -8.08, P = 0.015) an 展开更多
关键词 Cervical Cancer Long Noncoding RNA Nuclear-Enriched Abundant Transcript 1 Migration PI3K/Akt SignalingPathway Proliferation
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Fused monochromatic imaging acquired by single source dual energy CT in hepatocellular carcinoma during arterial phase: an initial experience 被引量:4
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作者 shun-yu Gao Xiao-Peng Zhang +5 位作者 Yong Cui Ying-Shi Sun Lei Tang Xiao-Ting Li Xiao-Yan Zhang Jun Shan 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第4期437-443,共7页
Objective: To explore whether single and fused monochromatic images can improve liver tumor detection and delineation by single source dual energy CT (ssDECT) in patients with hepatocellular carcinoma (HCC) durin... Objective: To explore whether single and fused monochromatic images can improve liver tumor detection and delineation by single source dual energy CT (ssDECT) in patients with hepatocellular carcinoma (HCC) during arterial phase. Methods: Fifty-seven patients with HCC who underwent ssDECT scanning at Beijing Cancer Hospital were enrolled retrospectively. Twenty-one sets of monochromatic images from 40 to 140 keV were reconstructed at 5 keV intervals in arterial phase. The optimal contrast-noise ratio (CNR) monochromatic images of the liver tumor and the lowest-noise monochromatic images were selected for image fusion. We evaluated the image quality of the optimal-CNR monochromatic images, the lowest-noise monochromatic images and the fused monochromatic images, respectively. The evaluation indicators included the spatial resolution of the anatomical structure, the noise level, the contrast and CNR of the tumor. Results: In arterial phase, the anatomical structure of the liver can be displayed most clearly in the 65-keV monochromatic images, with the lowest image noise. The optimal-CNR monochromatic images of HCC tumor were 50-keV monochromatic images in which the internal structural features of the liver tumors were displayed most clearly and meticulously. For tumor detection, the fused monochromatic images and the 50-keV monochromatic images had similar performances, and were more sensitive than 65-keV monochromatic images. Conclusions: We achieved good arterial phase images by fusing the optimal-CNR monochromatic images of the HCC tumor and the lowest-noise monochromatic images. The fused images displayed liver tumors and anatomical structures more clearly, which is potentially helpful for identifying more and smaller HCC tumors. 展开更多
关键词 Computed tomography (CT) dual energy hepatocellular carcinoma (HCC) image postprocessing comparative study
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Metal–Phenolic Network-Facilitated“Foe-to-Friend”Conversion of Melittin for Cancer Immunotherapy with Boosted Abscopal Effect
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作者 yuxin Guo Xinping Zhang +3 位作者 Shao-Zhe Wang Hui-Heng Feng shun-yu Wu Fu-Gen Wu 《Research》 SCIE EI CSCD 2023年第3期727-739,共13页
As a naturally occurring cytolytic peptide,melittin(Mel)has strong cytolytic activity and is a potent therapeutic peptide for cancer therapy.However,the serious hemolytic activity of Mel largely impedes its clinical a... As a naturally occurring cytolytic peptide,melittin(Mel)has strong cytolytic activity and is a potent therapeutic peptide for cancer therapy.However,the serious hemolytic activity of Mel largely impedes its clinical applications.In this work,based on the strong interactions between proteins/peptides and polyphenols,we develop a tannic acid–Fe^(3+)metal–phenolic network(MPN)-based strategy that can convert Mel from foe to friend via shielding its positive charges and reducing its hemolytic activity.Besides,an immune adjuvant resiquimod(R848)is also introduced for immunostimulation,affording the final Mel-and R848-coloaded nanodrug.The Mel-caused membrane disruption can induce immunogenic cell death for immunostimulation,R848 can act as an immune adjuvant to further facilitate the immunostimulatory effect,and the tannic acid–Fe^(3+)MPN-mediated Fenton reaction can produce reactive oxygen species for cancer treatment.Further experiments reveal that the nanodrug can effectively cause immunogenic cell death of tumor cells and arouse robust intratumoral and systemic antitumor immunostimulation.In the bilateral tumor-bearing mouse models,the nanodrug considerably destroys the primary tumor and also boosts the abscopal effect to ablate the distant tumor.Collectively,the MPN-facilitated“foe-to-friend”strategy may promote the practical applications of Mel and foster the development of cancer immunotherapeutics. 展开更多
关键词 STIMULATION loaded considerably
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Improvement of the carrier distribution with GaN/InGa N/AlGaN/InGaN/GaN composition-graded barrier for InGaN-based blue light-emitting diode 被引量:1
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作者 Min Guo Zhi-You Guo +2 位作者 Jing Huang Yang Liu shun-yu Yao 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期499-504,共6页
In Ga N light-emitting diodes(LEDs) with Ga N/In Ga N/Al Ga N/In Ga N/Ga N composition-graded barriers are proposed to replace the sixth and the middle five Ga N barriers under the condition of removing the electron... In Ga N light-emitting diodes(LEDs) with Ga N/In Ga N/Al Ga N/In Ga N/Ga N composition-graded barriers are proposed to replace the sixth and the middle five Ga N barriers under the condition of removing the electron blocking layer(EBL)and studied numerically in this paper. Simulation results show that the specially designed barrier in the sixth barrier is able to modulate the distributions of the holes and electrons in quantum well which is adjacent to the specially designed barrier. Concretely speaking, the new barrier could enhance both the electron and hole concentration remarkably in the previous well and reduce the hole concentration for the latter one to some extent along the growth direction. What is more,a phenomenon, i.e., a better carrier distribution in all the wells, just appears with the adoption of the new barriers in the middle five barriers, resulting in a much higher light output power and a lower efficiency droop than those in a conventional LED structure. 展开更多
关键词 composition-graded barriers light-emitting diodes carrier distribution
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Refrigerant Control Strategies for Residential Air-Conditioning and Heat-Pump System 被引量:1
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作者 SU shun-yu,ZHANG Chun-zhi,CHEN Jian(College of Urban Construction,Wuhan University of Science and Technology,Wuhan,Hubei 430070,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期91-95,共5页
This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-conditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this system.... This paper simulated the optimal refrigerant charge inventory of a refrigeration system in air-conditioning operation and heat-pump operation respectively,and studied the refrigerant control strategies in this system.The void fraction in two-phase fluid region was calculated by Harms model.And based on distributed parameter model and Harms model,the refrigerant charge inventory in condenser and evaporator were calculated and analyzed in air-conditioning conditions and heat-pump conditions,respectively.The calculating results of different refrigerant mass between refrigeration and heating conditions indicate that the optimal refrigerant charge inventory in heat-pump conditions is lower than that in air-conditioning conditions.To avoid the decrease of COP due to the surplus refrigerant in heating conditions,we introduced the liquid reservoir control method and associate capillary control method.Both of them could increase the heating capacity of the air-source heat pump.The difference of optimal refrigerant charge inventory in air-conditioning and heat-pump system can be controlled by the liquid reservoir or the associate capillary. 展开更多
关键词 air-source HEAT PUMP control strategy distributed PARAMETER model CHARGE INVENTORY
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High spatial resolution spectroscopy of G292.0+1.8 with Chandra 被引量:1
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作者 Xue-Juan Yang Xiao-Qin Liu +1 位作者 shun-yu Li Fang-Jun Lu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第10期1279-1288,共10页
We present high spatial resolution X-ray spectroscopy of supernova rem- nant G292.0+1.8 made with Chandra observations. The X-ray emitting region of this remnant was divided into 25 × 25 pixels with a scale of 2... We present high spatial resolution X-ray spectroscopy of supernova rem- nant G292.0+1.8 made with Chandra observations. The X-ray emitting region of this remnant was divided into 25 × 25 pixels with a scale of 20" × 20" each. Spectra of 328 pixels were created and fitted with an absorbed one component non-equilibrium ionization model. With the spectral analysis results, we obtained maps of absorbing column density, temperature, ionization age and abundances for O, Ne, Mg, Si, S and Fe. The abundances of O, Ne and Mg show tight correlations between each other in the range of about two orders of magnitude, suggesting that they are all from explo- sive C/Ne burning. Meanwhile, the abundances of Si and S are also well correlated, indicating that they are the ashes of explosive O-burning or incomplete Si-burning. The Fe emission lines are not prominent in the whole remnant, and their abundance is significantly reduced, indicating that the reverse shock may not have propagated to the Fe-rich ejecta. Based on relative abundances of O, Ne, Mg, Si and Fe to Si, we suggest a progenitor mass of 25 - 30 M⊙ for this remnant. 展开更多
关键词 ISM supernova remnants -- ISM INDIVIDUAL G292.0+1.8
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