期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
基于频率估计和信号重构的移频干扰抑制方法
1
作者 金珊珊 李欣 刘晨 《现代防御技术》 北大核心 2022年第6期97-102,共6页
移频干扰针对线性调频信号的距离-多普勒耦合特性,能够产生高逼真的假目标。根据脉冲压缩后回波的峰值特性和去斜处理的原理,提出了基于信号重构和对消的抑制方法。首先,对去斜处理后的信号频率进行估计,并根据估计的频率,对去斜处理后... 移频干扰针对线性调频信号的距离-多普勒耦合特性,能够产生高逼真的假目标。根据脉冲压缩后回波的峰值特性和去斜处理的原理,提出了基于信号重构和对消的抑制方法。首先,对去斜处理后的信号频率进行估计,并根据估计的频率,对去斜处理后的干扰信号进行重构;其次,对去斜处理后的信号,定义了归一化平均检测门限,并以归一化平均检测门限最小作为干扰抑制的目标函数;最后,通过全局搜索的方式计算得到归一化平均检测门限最小时对应的干扰抑制因子,并通过对消来实现干扰抑制。计算机仿真表明,输出信号的脉压结果中,剩余干扰分量的能量比目标回波低20 dB以上,体现了所提出方法可以有效实现对多次移频干扰的抑制。 展开更多
关键词 频率估计 信号重构 移频干扰 干扰抑制因子 归一化平均检测门限
下载PDF
Lentivirus-mediated shRNA interference targeting STAT3 inhibits human pancreatic cancer cell invasion 被引量:19
2
作者 Guang Yan Chen Huang Jun Cao Ke-Jian Huang Tao Jiang Zheng-Jun Qiu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第30期3757-3766,共10页
AIM: To investigate RNA interference targeting signal transducer and activator of transcription-3 (STAT3) on invasion of human pancreatic cancer cells.METHODS: We constructed three plasmids of RNA interference tar... AIM: To investigate RNA interference targeting signal transducer and activator of transcription-3 (STAT3) on invasion of human pancreatic cancer cells.METHODS: We constructed three plasmids of RNA interference targeting the STAT3 gene. After LV (lentivirus)-STAT3siRNA (STAT3 small interfering RNA) the vector was transfected into the human pancreatic cell line, SW1990 and cell proliferation was measured by the MTT assay. Flow cytometry was used to assess cell cycle. Vascular endothelial growth favor (VEGF) and matrix metalloproteinase-2 (MMP-2) mRNA and protein expression were examined by quantitative PCR and western blotting, respectively. The invasion ability of SW1990 cells was determined by cell invasion assay.RESULTS: We successfully constructed the LVSTAT3siRNA lentivirus vector and proved that it can suppress expression of STAT3 gene in SW1990 cells. RNA interference of STAT3 by the LV-STAT3siRNA construct significantly inhibited the growth of SW1990 cells, in addition to significantly decreasing both VEGF and MMP-2 mRNA and protein expression. Moreover, suppression of STAT3 by LV-STAT3siRNA decreased the invasion ability of SW1990 cells.CONCLUSION: The STAT3 signaling pathway may provide a novel therapeutic target for the treatment of pancreatic cancer since it inhibits the invasion ability of pancreatic cancer cells. 展开更多
关键词 Signal transducer and activator of transcription3 RNA interference Lentivirus vector Pancreatic cancercells INVASION
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部