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INHIBITION OF PROLIFERATION OF HUMAN BREAST CANCER MCF-7 CELLS BY SMALL INTERFERENCE RNA AGAINST LRP16 GENE 被引量:1
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作者 韩为东 赵亚力 +4 位作者 李琦 母义明 李雪 宋海静 陆祖谦 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2004年第4期239-245,共7页
Objective: Our previous studies have firstly demonstrated that 17β -E2 up-regulates LRP16 gene expression in human breast cancer MCF-7 cells, and ectopic expression of the LRP16 gene promotes MCF-7 cells proliferatio... Objective: Our previous studies have firstly demonstrated that 17β -E2 up-regulates LRP16 gene expression in human breast cancer MCF-7 cells, and ectopic expression of the LRP16 gene promotes MCF-7 cells proliferation. Here, the effects of the LRP16 gene expression on growth of MCF-7 human breast cancer cells and the mechanism were further studied by establishing two stably LRP16-inhibitory MCR-7 cell lines. Methods: Hairpin small interference RNA (siRNA) strategy, by which hairpin siRNA was released by U6 promoter and was mediated by pLPC-based retroviral vector, was adopted to knockdown endogenous LRP16 level in MCF-7 cells. And the hairpin siRNA against green fluorescence protein (GFP) was used as the negative control. The suppressant efficiency of the LRP16 gene expression was confirmed by Nothern blot. Cell proliferation assay and soft agar colony formation assay were used to determine the status of the cells proliferation. Cell cycle checkpoints including cyclin E and cyclin D1 were examined by Western blot. Results: The results from cell proliferation assays suggested that down-regulation of LRP16 gene expression is capable of inhibiting MCF-7 breast cancer cell growth and down-regulation of the LRP16 gene expression is able to inhibit anchorage-independent growth of breast cancer cells in soft agar. We also demonstrated that cyclin E and cyclin D1 proteins were much lower in the LRP16-inhibitory cells than in the control cells. Conclusion: These data suggest that LRP16 gene play an important role in MCF-7 cells proliferation by regulating the pathway of the G1/S transition and may function as an important modulator in regulating the process of tumorigenesis in human breast. 展开更多
关键词 EsTRADIOL LRP16 small interference RNA MCF-7 Proliferation soft agar assay G1/s control
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F-interference law generation and its feature recognition 被引量:5
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作者 Qiu Jinming Zhang Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期777-783,共7页
By using two-directional S-rough sets, the concepts of (f, f)-interference generation and (f, f)- interference law generation of knowledge, F-interference generation and F-interference law generation of two-direct... By using two-directional S-rough sets, the concepts of (f, f)-interference generation and (f, f)- interference law generation of knowledge, F-interference generation and F-interference law generation of two-directional S-rough sets are proposed. Based on the concepts above, the relation theoreras between F-interference loss and F-interference degree, the relation theorems between F-interference loss law and F-interference degree law, the dis- cernibility theorems between F-interference and F-interference law are presented. At last, the recognition criterion of F-interference law and its application are given. 展开更多
关键词 two-directional s-rough sets F-interference F-interference law discernibility theorem of F- interference recognition of F-interference law applications.
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Second-order interference of two independent and tunable single-mode continuous-wave lasers 被引量:1
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作者 刘建彬 卫栋 +5 位作者 陈辉 周宇 郑淮斌 高宏 李福利 徐卓 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期194-199,共6页
The second-order temporal interference of two independent single-mode continuous-wave lasers is discussed by em- ploying two-photon interference in Feynman's path integral theory. It is concluded that whether the sec... The second-order temporal interference of two independent single-mode continuous-wave lasers is discussed by em- ploying two-photon interference in Feynman's path integral theory. It is concluded that whether the second-order temporal interference pattern can or cannot be retrieved via two-photon coincidence counting rate is dependent on the resolution time of the detection system and the frequency difference between these two lasers. Two identical and tunable single-mode continuous-wave diode lasers are employed to verify the predictions. These studies are helpful to understand the physics of two-photon interference with photons of different spectra. 展开更多
关键词 second-order temporal beating two-photon interference Feynman's path integral theory
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50 Gbit/s前传光模块关键技术研究与应用展望
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作者 盛夏 马涛 +1 位作者 刘昊 冯佳 《电信科学》 北大核心 2024年第5期23-37,共15页
随着全球5G网络的规模化商用及移动互联网流量的迅猛增长,更为丰富的无线频谱资源得以释放,高速率光模块在无线前传网络中的需求日益凸显。聚焦于50 Gbit/s前传光模块的关键技术,深入剖析了前传网络的两种主要组网方式,分析了前传链路... 随着全球5G网络的规模化商用及移动互联网流量的迅猛增长,更为丰富的无线频谱资源得以释放,高速率光模块在无线前传网络中的需求日益凸显。聚焦于50 Gbit/s前传光模块的关键技术,深入剖析了前传网络的两种主要组网方式,分析了前传链路的典型传输距离及链路损耗情况,探讨了10 km场景下粗波分复用(coarse wavelength division multiplex,CWDM)中各波长的最大色散值和最小色散值,并研究了相应的色散补偿策略,通过实验验证了不同多径干扰(multi-path interference,MPI)强度下系统光功率代价的变化,详细分析了多径干扰噪声对系统误码性能的潜在影响,为前传光模块参数的优化提供了重要的理论依据。此外,深入研究了50 Gbit/s前传光模块的光电芯片技术方案,对多种不同类型光模块的参数性能进行了严格的测试,提出了针对50 Gbit/s前传光模块光电接口参数的标准化建议,详细介绍了当前50 Gbit/s前传光模块在国内外的标准现状,并展望了未来应用的发展趋势。 展开更多
关键词 5G网络 50 Gbit/s前传光模块 色散 多径干扰 光电接口参数
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Second-order temporal interference of two independent light beams at an asymmetrical beam splitter
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作者 刘建彬 王婧婧 徐卓 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期187-193,共7页
The second-order temporal interference of classical and nonclassical light at an asymmetrical beam splitter is discussed based on two-photon interference in Feynman's path integral theory. The visibility of the secon... The second-order temporal interference of classical and nonclassical light at an asymmetrical beam splitter is discussed based on two-photon interference in Feynman's path integral theory. The visibility of the second-order interference pattern is determined by the properties of the superposed light beams, the ratio between the intensities of these two light beams, and the reflectivity of the asymmetrical beam splitter. Some requirements about the asymmetrical beam splitter have to be satisfied in order to ensure that the visibility of the second-order interference pattern of nonclassical light beams exceeds the classical limit. The visibility of the second-order interference pattern of photons emitted by two independent single-photon sources is independent of the ratio between the intensities. These conclusions are important for the researches and applications in quantum optics and quantum information when an asymmetrical beam splitter is employed. 展开更多
关键词 two-photon interference Feynman's path integral theory asymmetrical beam splitter
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S-rough Laws and Its Dependent Separation by F-Interference
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作者 邱锦明 颜建军 史开泉 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期213-216,共4页
By employing function S-rough sets,the concepts of f-interference generation and separation of law,and the F-interference generation and separation of S-rough laws were proposed. Base on the concepts above,the F-inter... By employing function S-rough sets,the concepts of f-interference generation and separation of law,and the F-interference generation and separation of S-rough laws were proposed. Base on the concepts above,the F-interference relation theorems,the F-interference discernibility theorem,the dependent separation theorem by interfereence,and the dependent separation principle by interference were presented; finally the application was given. By employing F-interference dependence and separation of S-rough laws,the changes of characteristic of dynamic systemic regularities could be recognized. 展开更多
关键词 function s-rough sets s-rough laws f-interference F-interference interference generation interference discernibility dependent separation
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Interference Experiment with a Transparent Mask Rejects Wave Models of Light
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作者 John C. Hodge 《Optics and Photonics Journal》 2019年第6期75-80,共6页
Young’s double-slit experiment shows characteristics of light that are modeled as indicating a wave nature of light. Other experiments suggest a particle model of light. An experiment is performed with the Fraunhofer... Young’s double-slit experiment shows characteristics of light that are modeled as indicating a wave nature of light. Other experiments suggest a particle model of light. An experiment is performed with the Fraunhofer pattern from a first mask impinging on a transparent second mask with a slit. The screen pattern is an interference pattern such as produced in Young’s Experiment. An opaque strip between the first and second mask blocks the light of the center maxima from the first mask. The screen interference fringes remained. Moving the glass mask so the slit is removed from light shows the necessity of a slit in the second mask. This suggests a Newtonian type of light model. This experiment rejects the wave models of light. 展开更多
关键词 Diffraction interference Young’s EXPERIMENT LIGHT PHOTON
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Failure to Recover from Proactive Semantic Interference Differentiates Amnestic Mild Cognitive Impairment and PreMCI from Normal Aging after Adjusting for Initial Learning Ability
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作者 Rosie E.Curiel Elizabeth A.Crocco +5 位作者 Arlene Raffo Salvador M.Guinjoan Charles Nemeroff Ailyn Penate Daema Piña David A.Loewenstein 《Advances in Alzheimer's Disease》 2018年第2期50-61,共12页
Background: There is increasing evidence that the failure to recover from proactive semantic interference (frPSI) may be an early cognitive marker of preclinical Alzheimer’s disease (AD). However, it is unclear wheth... Background: There is increasing evidence that the failure to recover from proactive semantic interference (frPSI) may be an early cognitive marker of preclinical Alzheimer’s disease (AD). However, it is unclear whether frPSI effects reflect deficiencies in an individual’s initial learning capacity versus the actual inability to learn new semantically related targets. Objective: The current study was designed to adjust for learning capacity and then to examine the extent to which frPSI, proactive semantic interference (PSI) and retroactive semantic interference (RSI) effects could differentiate between older adults who were cognitively normal (CN), and those diagnosed with either Pre-Mild Cognitive Impairment (PreMCI) or amnestic MCI (aMCI). Methods: We employed the LASSI-L cognitive stress test to examine frPSI, PSI and RSI effects while simultaneously controlling for the participant’s initial learning capacity among 50 CN, 35 aMCI, and 16 PreMCI participants who received an extensive diagnostic work-up. Results: aMCI and PreMCI participants showed greater frPSI deficits (50% and 43.8% respectively) compared to only 14% of CNparticipants. PSI effects were observed for aMCI but not PreMCI participants relative to their CN counterparts. RSI failed to differentiate between any of the study groups. Conclusion: By using participants as their own controls and adjusting for overall learning and memory, it is clear that frPSI deficits occur with much greater frequency in individuals at higher risk for Alzheimer’s disease (AD), and likely reflect a failure of brain compensatory mechanisms. 展开更多
关键词 MCI Alzheimer’s Disease semantic interference Memory
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Interference Mitigation in Satellite Personal Communication Networks Using Adaptive Antenna Arrays and Filtering Technique
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作者 Sunday E. Iwasokun Michael O. Kolawole 《Wireless Engineering and Technology》 2010年第2期88-91,共4页
We address the problem of interference as related to Satellite Personal Communication Networks (S-PCNs). Basic low Earth orbit (LEO) constellation is considered. The paper uses combined adaptive antenna arrays and ada... We address the problem of interference as related to Satellite Personal Communication Networks (S-PCNs). Basic low Earth orbit (LEO) constellation is considered. The paper uses combined adaptive antenna arrays and adaptive filtering technique. This hybrid linear adaptive technique provides improved performance eliminating interference, particularly uncorrelated signals residing in the antenna sidelobes. 展开更多
关键词 s-PCN LEO ADAPTIVE Array ANTENNAs ADAPTIVE FILTERING interference ELIMINATION
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导叶翼型优化对水泵水轮机“S”特性的影响
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作者 李琪飞 黄腾 +2 位作者 郑非 辛路 谢耕达 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2023年第8期1354-1360,共7页
为了改善水泵水轮机“S”特性,本文以某水泵水轮机模型机为研究对象,采用SST k-ω湍流模型开展水泵水轮机全流道三维数值计算。通过优化活动导叶翼型,得出n 11-Q 11模拟曲线和机组“S”特性改善情况,并对优化活动导叶翼型后的机组的无... 为了改善水泵水轮机“S”特性,本文以某水泵水轮机模型机为研究对象,采用SST k-ω湍流模型开展水泵水轮机全流道三维数值计算。通过优化活动导叶翼型,得出n 11-Q 11模拟曲线和机组“S”特性改善情况,并对优化活动导叶翼型后的机组的无叶区进行了压力脉动分析。结果表明:优化活动导叶翼型对机组的“S”特性存在一定改善效果;翼型优化后机组的效率虽然有小幅度下降,但是整体效率依然保持在90%以上;无叶区压力脉动主要是由活动导叶区域出流,转轮叶片工作面发生冲击导致的分流以及转轮叶片与活动导叶组成的动静叶栅干涉效应引起的。改型后的活动导叶降低了无叶区的压力脉动幅值,在一定程度上提升了水泵水轮机的安全系数。 展开更多
关键词 水泵水轮机 s”特性曲线 活动导叶 翼型设计 数值计算 动静叶栅干涉 安全系数
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基于广义S变换与数学形态学的局部放电窄带干扰抑制方法 被引量:3
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作者 饶显杰 徐忠林 +6 位作者 龙林 李珏潇 杨小兵 杨永鹏 苟杨 冯阳 周凯 《电网技术》 EI CSCD 北大核心 2023年第3期1299-1307,共9页
针对高压电力设备局部放电信号受周期性窄带干扰影响大的问题,提出了一种基于广义S变换与数学形态学的局部放电窄带干扰抑制方法。该方法可以从染噪局部放电(partial discharge,PD)信号中分离出原始PD信号和窄带干扰信号的时频谱图,从... 针对高压电力设备局部放电信号受周期性窄带干扰影响大的问题,提出了一种基于广义S变换与数学形态学的局部放电窄带干扰抑制方法。该方法可以从染噪局部放电(partial discharge,PD)信号中分离出原始PD信号和窄带干扰信号的时频谱图,从而在时频域内准确辨识出窄带干扰和原始PD信号,避免强能量的窄带干扰掩盖原始PD信号时频特征的问题。再利用总体最小二乘不变旋转矢量技术准确估计窄带干扰的特征参数,以抑制染噪PD信号中窄带干扰。对仿真和实测PD信号开展窄带干扰的抑制测试,测试结果表明:该文所提方法可以有效分离出染噪PD信号时频谱图中窄带干扰和PD信号,提高了时频分析的准确率;同时相比于传统的快速傅里叶变换(fast Fourier transform,FFT)算法谱最小熵解卷积滤波法和自适应奇异值分解法,该文方法能够有效抑制小幅值的窄带干扰,具备更好的窄带干扰抑制效果,以恢复局放信号的波形特征。 展开更多
关键词 局部放电信号 窄带干扰抑制 时频谱图 广义s变换 数学形态学
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SO_(2)对电化学传感器测定H_(2)S的影响
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作者 付福军 张寅卯 +4 位作者 张勇飞 卢鑫 姜英伟 强景云 彭志敏 《当代化工》 CAS 2023年第5期1043-1047,共5页
H_(2)S是固定污染源废气监测的重要成分。该研究选用几款H_(2)S电化学传感器和一款紫外荧光H_(2)S在线分析仪进行比对实验,系统研究了SO_(2)对H_(2)S测定结果的干扰程度、SO_(2)对H_(2)S电化学传感器灵敏度的影响,并探讨了SO_(2)对H_(2)... H_(2)S是固定污染源废气监测的重要成分。该研究选用几款H_(2)S电化学传感器和一款紫外荧光H_(2)S在线分析仪进行比对实验,系统研究了SO_(2)对H_(2)S测定结果的干扰程度、SO_(2)对H_(2)S电化学传感器灵敏度的影响,并探讨了SO_(2)对H_(2)S的干扰产生的原因。研究结果表明:紫外荧光分析仪测定H_(2)S时,示值和灵敏度不受固定污染源废气中SO_(2)的干扰;电化学传感器测定固定污染源废气中H_(2)S时,SO_(2)会对H_(2)S测定值有影响,SO_(2)质量分数越高,对H_(2)S测定值的干扰越大,而即使100μg·g^(-1)的SO_(2)仍然使H_(2)S示值增大很多;SO_(2)质量分数越大,H_(2)S电化学传感器的灵敏度降低越多。 展开更多
关键词 sO_(2) H_(2)s 电化学 干扰程度 灵敏度
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消除铁对铬天青S分光光度法测定铝的干扰研究
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作者 王小平 刘忠莹 +5 位作者 张定秋 钟洋 陆阳 朱敏敏 郑红毅 王鑫 《中国食品添加剂》 CAS 北大核心 2023年第11期168-173,共6页
为消除铬天青S分光光度法测定臭豆腐中铝时铁带来的干扰,采用氢氧化钠溶液对铁和铝进行分离,并对方法进行优化。结果表明:不对臭豆腐消解液进行处理,采用铬天青S分光光度法测定其铝含量,当溶液铝含量一定时,溶液中铁含量越高,测得的结... 为消除铬天青S分光光度法测定臭豆腐中铝时铁带来的干扰,采用氢氧化钠溶液对铁和铝进行分离,并对方法进行优化。结果表明:不对臭豆腐消解液进行处理,采用铬天青S分光光度法测定其铝含量,当溶液铝含量一定时,溶液中铁含量越高,测得的结果越比真实值偏高,当溶液铁含量较高且一定,铝含量越高,测得的结果越接近真实值。采用优化后的方法对含有大量铁的臭豆腐消解液进行处理后,用铬天青S分光光度法测定其铝,测定结果与电感耦合等离子体质谱法测定的结果都没有显著性差异(P>0.05);而铬天青S分光光度法测定未处理消解液的铝,其结果都显著高于(P<0.05)电感耦合等离子体质谱法测定的结果。因此,通过本方法对含有大量铁的臭豆腐消解进行处理后,采用铬天青S分光光度法能够准确测定样品中铝。 展开更多
关键词 铬天青s 分光光度法 干扰消除
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杨氏干涉实验中双孔的振动对衬比度的影响
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作者 骆素华 姜向前 《物理通报》 CAS 2024年第7期105-107,112,共4页
研究了杨氏干涉实验中双孔的振动对衬比度的影响.利用复振幅叠加方法给出了当两个孔做振动方向相反的简谐振动时一对双孔对任一场点、任意时刻的光强表达式,进而给出双孔做简谐振动时双孔的分布函数.利用分布函数得到干涉场的稳态分布,... 研究了杨氏干涉实验中双孔的振动对衬比度的影响.利用复振幅叠加方法给出了当两个孔做振动方向相反的简谐振动时一对双孔对任一场点、任意时刻的光强表达式,进而给出双孔做简谐振动时双孔的分布函数.利用分布函数得到干涉场的稳态分布,由光场的稳态分布得到衬比度,发现衬比度随位置呈一个振幅衰减的拉比振荡形式. 展开更多
关键词 杨氏干涉 衬比度 拉比振荡
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基于混合干扰模型的多信道Mesh网络调度算法 被引量:5
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作者 孙懋珩 郑煜 周轩 《计算机工程与应用》 CSCD 北大核心 2010年第35期90-94,103,共6页
研究了多信道无线Mesh网络中的调度及信道分配问题,设计了一种综合协议干扰模型与物理干扰模型的混合干扰模型,并在此干扰模型下提出了一种集中式调度算法。该算法在目前普遍使用的协议干扰模型的基础上,考虑了无线链路的物理传输特性:... 研究了多信道无线Mesh网络中的调度及信道分配问题,设计了一种综合协议干扰模型与物理干扰模型的混合干扰模型,并在此干扰模型下提出了一种集中式调度算法。该算法在目前普遍使用的协议干扰模型的基础上,考虑了无线链路的物理传输特性:即使存在一定的干扰,也可以成功接收发射端发送的数据。模拟实验表明该算法可以提高Mesh网络中链路的并行性,有效减少总传输时间。 展开更多
关键词 无线Mesh网络(WMN) 调度 协议干扰模型 物理干扰模型 混合干扰模型 信道分配
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DFT扩频广义多载波系统的SINR性能分析 被引量:4
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作者 芮赟 李明齐 +3 位作者 周秦英 张小东 易辉跃 胡宏林 《通信学报》 EI CSCD 北大核心 2008年第6期51-56,共6页
针对离散傅立叶变换扩频的广义多载波系统(DFT-S-GMC),提出一种信干噪比(SINR)的性能分析方法。该方法基于DFT-S-GMC收发机频域等效的简化实现结构,利用信道频率响应和噪声方差,接收端采用最小均方误差(MMSE)均衡,分析得到了SINR的闭合... 针对离散傅立叶变换扩频的广义多载波系统(DFT-S-GMC),提出一种信干噪比(SINR)的性能分析方法。该方法基于DFT-S-GMC收发机频域等效的简化实现结构,利用信道频率响应和噪声方差,接收端采用最小均方误差(MMSE)均衡,分析得到了SINR的闭合表达式,并考虑了信道均衡后时域复用的数据块(IFBT符号)之间的残余干扰,而且,本方法很容易扩展到一发多收的情况。仿真表明,多径信道下基于该等效SINR的误块率(BLER)性能曲线能很好地匹配系统在高斯白噪声信道下的性能曲线。 展开更多
关键词 DFT-s-GMC 信干噪比 滤波器组 频域结构
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针对SARS冠状病毒S蛋白的RNAi设计 被引量:5
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作者 林剑萍 于永利 王丽颖 《生物技术通讯》 CAS 2004年第4期335-337,共3页
为研究SARS冠状病毒的RNA干涉,以S蛋白为目标选取16个RNA干涉的靶序列,并设计用于体内转录形成以U6为启动子的siRNA发夹结构的DNA,拟将设计的DNA瞬时转染靶细胞,用定量RT-PCR法确定目标RNA被干涉的程度,用Westernblot在蛋白质水平上进... 为研究SARS冠状病毒的RNA干涉,以S蛋白为目标选取16个RNA干涉的靶序列,并设计用于体内转录形成以U6为启动子的siRNA发夹结构的DNA,拟将设计的DNA瞬时转染靶细胞,用定量RT-PCR法确定目标RNA被干涉的程度,用Westernblot在蛋白质水平上进行监测。针对SARS冠状病毒的RNAi设计为进一步研究奠定了理论基础,其工作的开展将在RNAi治疗、SARS冠状病毒基因功能研究、新药开发等方面发挥重要作用。 展开更多
关键词 sARs 冠状病毒 s蛋白 RNAI RNA干涉 小干扰RNA
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SKP2 siRNA对HL-60/A细胞周期及药物敏感性的影响 被引量:3
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作者 聂大年 黄克智 +6 位作者 尹松梅 肖洁 谢双锋 李益清 马丽萍 王秀菊 吴裕丹 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2010年第6期792-797,共6页
【目的】观察S期激酶相关蛋白2(SKP2)siRNA转染后耐阿霉素的HL-60细胞(HL-60/A)P27kip1及多药耐药相关蛋白MRP表达水平的变化,探讨其对细胞周期及药物敏感性的影响。【方法】siRNA转染HL-60/A细胞,荧光显微镜、流式细胞仪检测转染效率,R... 【目的】观察S期激酶相关蛋白2(SKP2)siRNA转染后耐阿霉素的HL-60细胞(HL-60/A)P27kip1及多药耐药相关蛋白MRP表达水平的变化,探讨其对细胞周期及药物敏感性的影响。【方法】siRNA转染HL-60/A细胞,荧光显微镜、流式细胞仪检测转染效率,RT-PCR、Western-blot检测转染后细胞SKP2、P27kip1、MRPmRNA及蛋白表达,流式细胞仪检测细胞周期,药物毒性分析CCK-8法检测细胞对化疗药物的敏感性。【结果】SKP2siRNA转染24h后,HL-60/A的SKP2mRNA及蛋白表达分别下调43%(P=0.020)和69.6%(P=0.003);P27kip1蛋白上调78.1%(P=0.049),P27kip1mRNA表达无明显变化;MRPmRNA及蛋白表达分别下调55%(P=0.001)和62.3%(P=0.001);G0/G1期细胞比例升高;细胞对阿霉素、柔红霉素、阿糖胞苷的敏感性分别提高1.15倍、4.79倍和3.76倍。【结论】SKP2siRNA下调HL-60/A细胞的SKP2表达可使P27kip1蛋白表达升高,细胞增殖周期延长;细胞耐药性的改善可能与MRP表达的降低有关。 展开更多
关键词 细胞周期 RNA干扰 s期激酶蛋白 多药耐药相关蛋白 白血病
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一种基于S变换的高频地波雷达瞬态干扰抑制方法 被引量:7
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作者 徐兴安 吴雄斌 +1 位作者 陈骁锋 沈志奔 《电子学报》 EI CAS CSCD 北大核心 2014年第3期602-606,共5页
针对高频地波雷达中出现的瞬态干扰问题,提出了基于S变换(Stockwell transforms)的瞬态干扰抑制方法.首先分析了两次FFT信号处理机制下瞬态干扰的时频特征;然后应用S变换对雷达信号进行时频分析,利用瞬态干扰在时频维扩展性不同的特点,... 针对高频地波雷达中出现的瞬态干扰问题,提出了基于S变换(Stockwell transforms)的瞬态干扰抑制方法.首先分析了两次FFT信号处理机制下瞬态干扰的时频特征;然后应用S变换对雷达信号进行时频分析,利用瞬态干扰在时频维扩展性不同的特点,实现瞬态干扰的检测;最后应用三层BP(Back Propagation)神经网络对海洋回波信号进行预测和恢复.该方法避免了海杂波抑制的步骤,具有计算量小、信号损失小的优点.现场实测数据分析表明,该方法能够有效抑制瞬态干扰,使回波多普勒谱信噪比提高达10dB,有效提高了雷达的抗干扰能力. 展开更多
关键词 高频地波雷达 瞬态干扰抑制 s变换 BP神经网络
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结合广义S变换和快速独立分量分析的局放信号中窄带干扰抑制方法 被引量:5
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作者 李向群 伍亚萍 +2 位作者 庄旭菲 吉飞敏 张燕 《现代电力》 北大核心 2022年第5期597-604,共8页
针对现有方法对局部放电(partial discharge,PD)信号中窄带干扰抑制效果较差的问题,提出了一种基于广义S变换和快速独立分量分析的窄带干扰抑制方案。该方案首先利用广义S变换对染噪PD信号进行时频分析,在染噪PD信号的时频分布图中,根... 针对现有方法对局部放电(partial discharge,PD)信号中窄带干扰抑制效果较差的问题,提出了一种基于广义S变换和快速独立分量分析的窄带干扰抑制方案。该方案首先利用广义S变换对染噪PD信号进行时频分析,在染噪PD信号的时频分布图中,根据窄带干扰和PD信号的不同时频特征,可以确定窄带干扰的特征区域;然后在窄带干扰的特征区域中,利用Candan算法对窄带干扰的频率进行估计;最后利用窄带干扰频率估计值和快速独立分量分析方法分离出PD信号,实现窄带干扰抑制。仿真和实测结果说明,所提方法可以有效抑制染噪PD信号中窄带干扰,并且能准确获取PD信号的波形特征,对比传统的奇异值分解方法和快速傅里叶变换滤波方法,文中方法对窄带干扰的抑制效果更好,残余干扰的能量较小。 展开更多
关键词 局部放电 窄带干扰 广义s变换 Candan算法 快速独立分量分析
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