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三氧化二砷对胃癌细胞SGC7901多药耐药的逆转作用及其机制

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药学学报 2007年第9期42卷 949-953页

作者：薛英威韩继广李宝馨杨宝锋哈尔滨医科大学附属第三医院腹外二科黑龙江哈尔滨150040 哈尔滨医科大学药学院黑龙江哈尔滨150086

研究三氧化二砷(arsenic trioxide,As2O3)对胃癌细胞多药耐药的逆转作用及其机制。逐渐递增长春新碱(VCR)的浓度诱导胃癌细胞株SGC7901产生多药耐药性(SGC7901/VCR)。MTT法测定药物对肿瘤细胞的杀伤作用;Western blotting检测肿瘤细胞... 详细信息

研究三氧化二砷(arsenic trioxide,As2O3)对胃癌细胞多药耐药的逆转作用及其机制。逐渐递增长春新碱(VCR)的浓度诱导胃癌细胞株SGC7901产生多药耐药性(SGC7901/VCR)。MTT法测定药物对肿瘤细胞的杀伤作用;Western blotting检测肿瘤细胞内P-糖蛋白(P-gp)、谷胱甘肽S-转移酶(GST-s)表达。结果表明,胃癌SGC7901/VCR细胞对长春新碱(VCR)、5-氟尿嘧啶(5-Fu)及表阿霉素的耐药倍数分别为16.56倍、2.69倍及13.05倍。经As2O3预处理24 h后,长春新碱、5-氟尿嘧啶及表阿霉素对SGC7901/VCR的耐药倍数显著下降(P<0.05)。SGC7901/VCR在静息时细胞内P-gp、GST-s蛋白表达显著高于SGC7901。而As2O3可使SGC7901/VCR细胞内P-gp、GST-s蛋白表达显著下降,但是对SGC7901无明显作用。从而证实As2O3部分逆转SGC7901/VCR的耐药性,其机制可能与P-gp、GST-s蛋白表达降低有关。

关键词：胃癌多药耐药三氧化二砷

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye Xiao-feng yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Experimental demonstration of 220-GHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun YU Mingxu WANG Xiongwei yang Qiutong ZHANG Jingwen TAN Bing ZHANG Ying WU yang HAN Peng TIAN Wen ZHOU Kaihui WANG feng ZHAO State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6G communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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基于阈上随机共振的弱信号双色中波红外图像融合

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红外与毫米波学报 2011年第6期30卷 546-550页

作者：蔺素珍杨风暴吉琳娜李香亭李盼中北大学电子测试技术国家重点实验室山西太原030051 中北大学仪器科学与动态测试教育部重点实验室山西太原030051

提出了基于阈上随机共振的弱信号双色中波红外图像融合方法.利用阈上随机共振分别增强两幅图像的弱信号,通过中值滤波对图像降噪,然后对降噪图像进行支持度变换融合,得到信息丰富、细节明显的融合图像.实验结果表明,融合图像的局部标准... 详细信息

提出了基于阈上随机共振的弱信号双色中波红外图像融合方法.利用阈上随机共振分别增强两幅图像的弱信号,通过中值滤波对图像降噪,然后对降噪图像进行支持度变换融合,得到信息丰富、细节明显的融合图像.实验结果表明,融合图像的局部标准差提高了247.7%、局部熵提高了45.52%、峰值信噪比分别提高了6.71%和6.65%,证明了该方法的有效性.

关键词：中波红外图像融合弱信号处理阈上随机共振

Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu yang feng Chunming yang Lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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正弦电压馈电的直线感应发射器加速特性

电机与控制学报 2010年第1期14卷 18-22页

作者：杨宝峰李耀华严陆光中国科学院电工研究所北京100190 中国科学院研究生院北京100049

为了给直线感应发射器实验平台的设计与实验提供前期理论参考,介绍了基于网孔矩阵法的直线感应发射器集中参数电路等效模型及其数值算法,对三相正弦电压激励下的直线感应发射器加速特性与电压初始相位、幅值、频率的关系进行了仿真分析... 详细信息

为了给直线感应发射器实验平台的设计与实验提供前期理论参考,介绍了基于网孔矩阵法的直线感应发射器集中参数电路等效模型及其数值算法,对三相正弦电压激励下的直线感应发射器加速特性与电压初始相位、幅值、频率的关系进行了仿真分析。仿真结果表明,对于结构参数确定的直线感应发射器,有最佳的电源电压初始相位、幅值和频率对应关系,可以实现其加速性能的充分发挥。

关键词：电磁发射直线感应发射器加速特性正弦电压馈电网孔矩阵法

急性髓系白血病患者线粒体DNA的D-loop区存在突变

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中国地方病学杂志 2006年第1期25卷 90-93页

作者：周晋孟然李丽敏杨宝峰哈尔滨医科大学第一临床学院血液科 150001 首都医科大学宣武医院神经科哈尔滨医科大学药学院

目的研究线粒体DNA的D-loop区突变与白血病发生、发展的关系。方法应用盐析法对8例初治的成人急性髓系白血病患者及其生母和正常无关对照者的外周血基因组DNA提取、线粒体基因D-loop区PCR扩增、序列测定,对比分析白血病患者的线粒体基因... 详细信息

目的研究线粒体DNA的D-loop区突变与白血病发生、发展的关系。方法应用盐析法对8例初治的成人急性髓系白血病患者及其生母和正常无关对照者的外周血基因组DNA提取、线粒体基因D-loop区PCR扩增、序列测定,对比分析白血病患者的线粒体基因D-loop区序列与其生母和健康无关对照者的线粒体基因D-loop区序列与标准剑桥线粒体基因D-loop区序列的差异。结果8例白血病患者中6例存在突变(突变率75%),共查出突变位点11个,突变类型均为D-loop区的T-C、A-C、G-A碱基替代突变。结论线粒体DNA的D-loop区在白血病患者中的突变率较高,D-loop区的突变在白血病发生发展过程中可能起作用。

关键词：线粒体基因白血病,早幼粒细胞,急性 DNA基因突变

Support effect and confinement effect of porous carbon loaded tin dioxide nanoparticles in high-performance CO_(2) electroreduction towards formate

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Chinese Chemical Letters 2025年第1期36卷 597-602页

作者： Xingxing Jiang Yuxin Zhao Yan Kong Jianju Sun Shangzhao feng Xin Lu Qi Hu Hengpan yang Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).Herein,we employ freestanding porous carbon fibers(PCNF)as an efficacious and stable support for the uniformly distributed SnO_(2)nanoparticles(SnO_(2)PCNF),thereby capitalizing on the synergistic support effect that arises from their strong *** one hand,the interaction between the SnO_(2)nanoparticles and the carbon support optimizes the electronic configuration of the active *** interaction leads to a noteworthy shift of the d-band center toward stronger intermediate adsorption energy,consequently lowering the energy barrier associated with CO_(2)*** a result,the Sn O_(2)PCNF realizes a remarkable CO_(2)RR performance with excellent selectivity towards formate(98.1%).On the other hand,the porous carbon fibers enable the uniform and stable dispersion of SnO_(2)nanoparticles,and this superior porous structure of carbon supports can also facilitate the exposure of the SnO_(2)nanoparticles on the reaction interface to a great ***,adequate contact between active sites,reactants,and electrolytes can significantly increase the metal utilization,eventually bringing forth a remarkable7.09 A/mg mass *** work might provide a useful idea for improving the utilization rate of metals in numerous electrocatalytic reactions.

关键词： CO_(2)electroreduction Support effect Porous carbon fiber Formate Mass activity

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铁路轨枕现状及发展

铁道工程学报 2007年第2期24卷 36-40页

作者：杨宝峰于春华铁道第三勘察设计院天津300251

研究目的:本文对轨枕的主要功能和分类方法加以论述,同时简述我国铁路轨枕的发展过程及存在的问题。研究方法:通过搜集资料了解我国铁路轨枕及城市轨道交通轨枕的发展历程;总结轨枕分类方法;介绍木枕、混凝土枕及城轨交通用特殊轨枕的... 详细信息

研究目的:本文对轨枕的主要功能和分类方法加以论述,同时简述我国铁路轨枕的发展过程及存在的问题。研究方法:通过搜集资料了解我国铁路轨枕及城市轨道交通轨枕的发展历程;总结轨枕分类方法;介绍木枕、混凝土枕及城轨交通用特殊轨枕的主要特点,并调查研究了各类轨枕在设计、制造、使用、养护维修中存在的问题。研究结果:提供了先进国家适用于高速铁路轨枕的发展动态,以及我国已运营4年的秦沈客运专线用轨道板和正处于设计招标阶段的京津城际轨道交通用轨道板等信息。研究结论:我国铁路轨枕及城市轨道交通轨枕的发展应遵循:增加混凝土枕类型以满足不同铺设条件的需要;提高混凝土枕的使用寿命,并开发研制轨枕新品种,适应我国铁路高速、重载以及城市轨道交通迅猛发展的需求。

关键词：铁路轨枕功能分类发展问题建议