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新能源扁线电机hairpin激光焊接头组织与性能分析
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作者 李远远 唐峰 柯凯 《焊接》 2024年第4期74-80,共7页
以新能源汽车扁线驱动电机为主体,探究了扁线电机制造过程中hairpin连接线的激光焊接工艺。通过焊点金相、高速摄像、拉力测试、硬度测试、扫描电镜等测试手段,验证了扁线电机连接线激光焊的制造工艺可行性和焊接质量可靠性。结果表明:... 以新能源汽车扁线驱动电机为主体,探究了扁线电机制造过程中hairpin连接线的激光焊接工艺。通过焊点金相、高速摄像、拉力测试、硬度测试、扫描电镜等测试手段,验证了扁线电机连接线激光焊的制造工艺可行性和焊接质量可靠性。结果表明:最佳焊接工艺参数为:激光功率3000 W、焊接速度200 mm/s、离焦量0 mm,焊接轨迹为ϕ2.5 mm的圆形、轨迹重复次数为5。无保护气体条件下激光焊接hairpin,焊点内部会出现气孔。能谱测试表明,气孔主要由氧元素引起。金相结果显示,焊点内部气孔率为0.5%,最大气孔直径为0.1 mm。拉力测试表明,拉力可达1414 N,远超标准要求。显微硬度测试结果显示,不同焊接热输入下激光焊hairpin接头焊缝区域和热影响区域均有一定程度的软化现象,但对焊缝区域的软化影响更为明显。 展开更多
关键词 扁线电机 hairpin 激光焊 组织 力学性能
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Target-induced Trivalent G-quadruplex/hemin DNAzyme for Colorimetric Detection of Hg^(2+) Based on an Exonuclease III Assisted Catalytic Hairpin Assembly
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作者 Zhenghua LIU Zhonghai LI 《Agricultural Biotechnology》 2024年第1期51-57,共7页
Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly fo... Mercury ion(Hg^(2+)),a highly noxious of heavy metalion,has detrimental effects on the ecological environment and human health.Herein,we have developed an exonuclease III(Exo III)assisted catalytic hairpin assembly formation of a trivalent G-quadruplex/hemin DNAzyme for colorimetric detection of Hg^(2+).A hairpin DNA(Hr)was designed with thymine-Hg^(2+)-thymine pairs that catalyzed by Exo III is prompted to happen upon binding Hg^(2+).A released DNA fragment triggers the catalytic assembly of other three hairpins(H1,H2,and H3)to form many trivalent G-quadruplex/hemin DNA enzymes for signal output.The developed sensor shows a dynamic range from 2 pM to 2μM,with an impressively low detection limit of 0.32 pM for Hg^(2+)detection.Such a sensor also has good selectivity toward Hg^(2+)detection in the presence of other common metal ions.This strategy shows the great potential for visual detection with portable type. 展开更多
关键词 G-quadruplex/hemin DNAzyme Multivalence Catalytic hairpin assembly Exonuclease III Signal amplification Colorimetric detection
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Hairpin绕组电机电压分布仿真计算与绝缘优化
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作者 黄文冬 王鹏 +1 位作者 朱英伟 马世金 《高电压技术》 EI CAS CSCD 北大核心 2023年第6期2458-2465,共8页
SiC逆变器驱动下Hairpin绕组电机承受高频、快速变化的复杂脉冲电应力,电机发生绝缘失效的可能性大为增加。为了解电机内部绕组的电压分布情况,对电机的绝缘可靠性做出评估,通过场路耦合有限元法对1台额定电压800 V的Hairpin绕组电机进... SiC逆变器驱动下Hairpin绕组电机承受高频、快速变化的复杂脉冲电应力,电机发生绝缘失效的可能性大为增加。为了解电机内部绕组的电压分布情况,对电机的绝缘可靠性做出评估,通过场路耦合有限元法对1台额定电压800 V的Hairpin绕组电机进行电压分布计算,得到了电机绕组中的电压分布规律。通过仿真和实测分析发现:电机的最大相地电压出现在三相绕组的入线端,数值为540V;匝间和相间电压最大值出现在绕组连接电路中串联顺序相距最远而空间上相邻的位置,分别为575V和923V;实测验证了计算结果的准确性,电压最大值处仿真与实测的误差为8%。基于仿真模型,发现30%的匝间或对地电容变化量对绝缘关键位置电压大小的影响不超过5%,并结合Dakin公式对电机的绝缘设计提出优化建议。以上结果可为Hairpin绕组电机的绝缘可靠性评估与绝缘设计提供借鉴。 展开更多
关键词 变频电机 有限元法 hairpin绕组 电压分布 绝缘优化
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SiC逆变器高频脉冲电压对Hairpin绕组绝缘安全的影响分析 被引量:5
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作者 鞠孝伟 程远 +2 位作者 杨明亮 崔淑梅 刘新华 《电工技术学报》 EI CSCD 北大核心 2021年第24期5115-5124,共10页
针对碳化硅(SiC)逆变器高频高dv/dt脉冲激励下的Hairpin绕组高电应力容易造成绝缘损伤的问题,该文对一台电动汽车用Hairpin绕组永磁同步电机进行了绕组匝间绝缘的电压应力计算与安全分析。首先,提出考虑双导体边耦合效应的Hairpin绕组... 针对碳化硅(SiC)逆变器高频高dv/dt脉冲激励下的Hairpin绕组高电应力容易造成绝缘损伤的问题,该文对一台电动汽车用Hairpin绕组永磁同步电机进行了绕组匝间绝缘的电压应力计算与安全分析。首先,提出考虑双导体边耦合效应的Hairpin绕组单匝线圈高频等效电路模型,提取电机绕组的高频分布参数,并基于场路耦合有限元方法建立Hairpin绕组的匝间电压计算模型;然后,得到SiC逆变器驱动下的绕组匝间绝缘电压应力,利用绕组匝间电压测试平台验证了模型与分析方法的正确性;最后,分析了不同匝间电压幅值、绝缘厚度、材料相对介电常数、匝间气隙长度等对气隙电场分布线的影响规律,以气隙电场分布线与Paschen曲线的关系为判据,给出了一种判断绕组绝缘是否发生放电的方法。 展开更多
关键词 SiC逆变器 永磁同步电机 hairpin绕组 电应力 匝间绝缘
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Growth inhibition induced by short hairpin RNA to silence survivin gene in human pancreatic cancer cells 被引量:18
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作者 Shen, Yong-Mei Yang, Xiao-Chun +3 位作者 Song, Miao-Li Qin, Chen-Hao Yang, Chen Sun, Yi-Hui 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第1期69-77,共9页
BACKGROUND: Survivin is known to be overexpressed in various human malignancies, including pancreatic cancer, and mediates cancer cell proliferation and tumor growth, so the regulation of this molecule could be a new ... BACKGROUND: Survivin is known to be overexpressed in various human malignancies, including pancreatic cancer, and mediates cancer cell proliferation and tumor growth, so the regulation of this molecule could be a new strategy for treating pancreatic cancer. In this study, short hairpin RNAs (shRNAs) specific to survivin were introduced into human pancreatic cancer Patu8988 cells to investigate the inhibitory effects on survivin expression and cell proliferation in vitro and in vivo. METHODS: Three kinds of shRNA specific to the survivin gene were designed and cloned into eukaryotic expression plasmid pGenesil-1 vector. Subsequently the recombinant plasmids were transfected into human pancreatic cancer Patu8988 cells with lipfectamine (TM) 2000 reagent. The mRNA and protein expressions of survivin in the transiently transfected Patu8988 cells were determined by RT-PCR, flow cytometry, and Western blotting analysis. The proliferation inhibition rates of stably transfected Patu8988 cells were determined by MTT assay. The antitumor activities of the three kinds of survivin-shRNA plasmids were evaluated in BALB/c nude mice inoculated with Patu8988 cells and bearing human pancreatic cancer. RESULTS: The three survivin-shRNA plasmids named pGenesil-1-survivin-1, pGenesil-1-survivin-2 and pGenesil-1-survivin-1+2 (with double interfering RNA sites) were successfully constructed, and were confirmed by restriction enzyme cutting and sequencing. At 48 hours after transfection, the expression of survivin mRNA and protein was inhibited in Patu8988 cells transfected with pGenesil-1-survivin-1, pGenesil-1-survivin-2, and pGenesil-1-survivin-1+2 when compared with that of either pGenesil-1-NC (with scrambled small interfering RNA) transfected cells or control cells (P<0.05). The MTT results showed that the proliferation rates of Patu8988 cells stably transfected with survivin-shRNA plasmids were reduced when compared with that of either pGenesil-1-NC transfected cells or control cells (P<0.01). Furthermore, when Patu8988 cells stably transfected with survivin-shRNA were injected into BALB/c nude mice, tumor growth was dramatically lower and the tumor was smaller than that of either pGenesil-1-NC transfected cells or control cells (P<0.01). The inhibitory effect of pGenesil-1-survivin-1 was the best among the three kinds of survivin-shRNA plasmids, but no combination of inhibitory effects was found in pGenesil-1-survivin-1+2. CONCLUSIONS: shRNAs specific to survivin have gene silencing effects and inhibit pancreatic cancer cell proliferation. shRNA activity against survivin could be of potential value in gene therapy for pancreatic cancer. However, shRNAs with double combining sites did not significantly enhance the interference compared with single site shRNAs, therefore further studies on this are needed. 展开更多
关键词 pancreatic neoplasms short hairpin RNA SURVIVIN pGenesil-1 vector
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Influence of Osteopontin Short Hairpin RNA on the Proliferation and Activity of Rat Vascular Smooth Muscle Cells 被引量:10
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作者 叶珊 孙玉梅 +3 位作者 别爱桂 周颖 刘佳妮 刘启功 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第2期144-149,共6页
To investigate the influence of osteopontin (OPN) short hairpin RNA (shRNA) on the proliferation and activity of rat vascular smooth muscle cells (VSMCs), the expressing vector of shRNA targeting OPN was constru... To investigate the influence of osteopontin (OPN) short hairpin RNA (shRNA) on the proliferation and activity of rat vascular smooth muscle cells (VSMCs), the expressing vector of shRNA targeting OPN was constructed and transferred into the rat VSMCs. After amplification and purification, pGenesil-1/OPNshRNA1 (PG1), pGenesil-1/OPNshRNA2 (PG2) and pGenesil-1/OPNshRNAHK (PGH) were transfected into the cultured rat VSMC by LipofectamineTM 2000. Transfected cells were visualized by using an inverted fluorescent microscope. VSMCs transfected by optimal recombined plasmid was selected by culturing in G418 48 h later. Nude cells and cells transfected by PGH were used as control. The expression levels of OPN mRNA and protein were assayed by RT-PCR and Western blotting. The OPN of VSMCs was suppressed by transfection of optimal recombined plasmid, and the changes in cell proliferation, adhesion and motility were evaluated by MTT, adhesion test and transwell chamber test. Levels of type I and Ⅲ collagen were measured with ELISA kit. Our results showed that VSMCs stably transfected by OPN shRNA accounted for over 50% of total cells. OPN mRNA and protein were reduced by 81% and 67% (P〈0.01) by PG1, 73% and 52% (P〈0.01) by PG2, respectively while no change was found in PGH and non-treated VSMCs. PG1 significantly suppressed the proliferation, adhesion, mobility of VSMCs and reduced the amount of type Ⅰ and Ⅲ collagen. It is concluded that recombinant plasmid can be success-fully transfected into VSMCs by LipofectamineTM 2000 and inhibit the expression of OPN. The proliferation, adhesion and mobility of VSMCs can be inhibited by knocking down OPN expression. Moreover, the transferring capability of cells is attenuated, and the secretion of type Ⅰ and Ⅲ collagen is inhibited aftter knocking-down of OPN expression. The study provides experimental evidence for clinical prevention of restenosis after percutaneous coronary intervention (PCI) by RNA interference (RNAi) technology. 展开更多
关键词 OSTEOPONTIN short hairpin RNA RNA interference vascular smooth muscle cells
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Inhibition of hepatitis B virus surface antigen expression by small hairpin RNA in vitro 被引量:8
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作者 Zheng-GangYang ZhiChen QinNi NingXu Jun-BinShao Hang-PingYao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第4期498-502,共5页
AIM: To explore the anti-hepatitis B virus effect of RNA interference (RNAi) using small hairpin RNA (shRNA)expression vector.METHODS: Hepatitis B virus surface antigen green fluorescent protein (HBs-GFP) fusion vecto... AIM: To explore the anti-hepatitis B virus effect of RNA interference (RNAi) using small hairpin RNA (shRNA)expression vector.METHODS: Hepatitis B virus surface antigen green fluorescent protein (HBs-GFP) fusion vector and shRNA expression vectors were constructed and cotransfected transiently into HepG2 cells. mRNAs extracted from HepG2 cells were detected by real-time PCR. Fluorescence of HBs-GFP protein was detected by fluorescence-activated cell sorting (FACS). The effective shRNA expression vector was transfected into HepG2.2.15 cells. HBsAg and HBeAg in HepG2.2.15 cells were analyzed by radioimmunoassay (RIA) method.RESULTS: FACS revealed that shRNA targeting at HBsAg reduced the GFP signal by 56% compared to the control.Real-time PCR showed that HBs-GFP mRNA extracted from HepG2 cells cotransfected with pAVU6+27 and HBs-GFP expression plasmids decreased by 90% compared to the empty vector control. The expressions of HBsAg and HBeAg were also inhibited by 43% and 64%, respectively.CONCLUSION: RNAi using shRNA expression vector can inhibit the expression of HBsAg, providing a fresh approach to screening the efficient small interfering RNAs (siRNAs). 展开更多
关键词 Hepatitis B Surface Antigens Small hairpin RNA RNA interference Gene expression
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Short hairpin RNA-mediated knockdown of nuclear factor erythroid 2-like 3 exhibits tumor-suppressing effects in hepatocellular carcinoma cells 被引量:3
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作者 Miao-Mei Yu Yue-Hua Feng +2 位作者 Lu Zheng Jun Zhang Guang-Hua Luo 《World Journal of Gastroenterology》 SCIE CAS 2019年第10期1210-1222,共13页
BACKGROUND Hepatocellular carcinoma(HCC) is one of the most common malignant tumors with high mortality-to-incidence ratios. Nuclear factor erythroid 2-like 3(NFE2 L3), also known as NRF3, is a member of the cap ‘n&#... BACKGROUND Hepatocellular carcinoma(HCC) is one of the most common malignant tumors with high mortality-to-incidence ratios. Nuclear factor erythroid 2-like 3(NFE2 L3), also known as NRF3, is a member of the cap ‘n' collar basic-region leucine zipper family of transcription factors. NFE2 L3 is involved in the regulation of various biological processes, whereas its role in HCC has not been elucidated.AIM To explore the expression and biological function of NFE2 L3 in HCC.METHODS We analyzed the expression of NFE2 L3 in HCC tissues and its correlation with clinicopathological parameters based on The Cancer Genome Atlas(TCGA) data portal. Short hairpin RNA(shRNA) interference technology was utilized to knock down NFE2 L3 in vitro. Cell apoptosis, clone formation, proliferation, migration,and invasion assays were used to identify the biological effects of NFE2 L3 in BEL-7404 and SMMC-7721 cells. The expression of epithelial-mesenchymal transition(EMT) markers was examined by Western blot analysis.RESULTS TCGA analysis showed that NFE2 L3 expression was significantly positively correlated with tumor grade, T stage, and pathologic stage. The qPCR and Western blot results showed that both the mRNA and protein levels of NFE2 L3 were significantly decreased after shRNA-mediated knockdown in BEL-7404 and SMMC-7721 cells. The shRNA-mediated knockdown of NFE2 L3 could induce apoptosis and inhibit the clone formation and cell proliferation of SMMC-7721 and BEL-7404 cells. NFE2 L3 knockdown also significantly suppressed the migration, invasion, and EMT of the two cell lines.CONCLUSION Our study showed that shRNA-mediated knockdown of NFE2 L3 exhibited tumor-suppressing effects in HCC cells. 展开更多
关键词 Nuclear factor ERYTHROID 2-like 3 Hepatocellular carcinoma The Cancer Genome Atlas Short hairpin RNA Epithelial-mesenchymal transition
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Short Hairpin RNA-mediated MDR1 Gene Silencing Increases Apoptosis of Human Ovarian Cancer Cell Line A2780/Taxol 被引量:3
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作者 Hui Xu Fan-zhen Hong +2 位作者 Su Li Ping Zhang Lin Zhu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2012年第2期138-142,共5页
Objective: Recurrent ovarian cancer is often resistant to drugs such as paclitaxel. Short hairpin RNA (shRNA) targeting MDRI, a gene involved in the process of drug resistance, may be a promising strategy to overco... Objective: Recurrent ovarian cancer is often resistant to drugs such as paclitaxel. Short hairpin RNA (shRNA) targeting MDRI, a gene involved in the process of drug resistance, may be a promising strategy to overcome drug resistance. Methods: Construction and identification of eukaryotic expression plasmid was transiently transfected into human ovarian cancer ce plasmid of shRNA targeting on MDR1 gene. The ne A2780/Taxol. Apoptosis was determined by flow cytometry using annexin V-FITC/PI double labeling. Expression of MDRI mRNA was detected by quantitative polymerase chain reaction (qPCR) and P-glycoprotein expression was detected using Western blot. Results The IC50 of paclitaxel in MDR1 shRNA-transfected group was significantly reduced (1.986±0.153)μmol/ml as compared with that in negative control (5.246±0.107)μmol/ml and empty vector-transfected group (5.212±0.075)μmol/ml (P〈0.05). The percent of the relative reverse sensitivity to paclitaxel on A2780/Taxol cells was 67.1%, and the apoptotic rate was significantly increased [(6.977±0.333)%] compared with control [(1.637±0.111)%] and empty vector-transfected group [(1.663±0.114)%] (P〈0.05). Expressions of MDR1 mRNA and P-glycoprotein were significantly reduced compared with control (P〈0.05). Conclusion: The present study demonstrated that the eukaryotic expression plasmid of shRNA targeting on MDRI inhibited the expression of MDRI effectively, thus enhance the sensitivity of A2780/Taxol cells to paclitaxel. 展开更多
关键词 Ovarian cancer Short hairpin RNA PACLITAXEL
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On hairpin vortex generation from near-wall streamwise vortices 被引量:7
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作者 Yinshan Wang Weixi Huang Chunxiao Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第2期139-152,共14页
The generation of a hairpin vortex from near-wall streamwise vortices is studied via the direct numerical simulation(DNS) of the streak transient growth in the minimal channel flow at Re_τ- 400.The streak profile i... The generation of a hairpin vortex from near-wall streamwise vortices is studied via the direct numerical simulation(DNS) of the streak transient growth in the minimal channel flow at Re_τ- 400.The streak profile is obtained by conditionally averaging the DNS data of the fully developed turbulent channel flow at the same Reynolds number.The near-wall streamwise vortices are produced by the transient growth of the streak which is initially subjected to the sinuous perturbation of the spanwise velocity.It is shown that the arch head of the hairpin vortex first grows from the downstream end of the stronger streamwise vortex and then connects with the weaker,opposite-signed streamwise vortex in their overlap region,forming a complete individual hairpin structure.The vorticity transport along the vortex lines indicates that the strength increase and the spatial expansion of the arch head are due to the stretching and the turning of the vorticity vector,respectively.The hairpin packets could be further produced from the generated individual hairpin vortex following the parent-offspring process. 展开更多
关键词 hairpin vortex Streamwise vortex Streak transient growth
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Influence of Osteopontin Short Hairpin RNA on the Proliferation and Invasion of Human Renal Cancer Cells 被引量:2
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作者 柳昊 陈安民 +1 位作者 郭风劲 袁林 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第1期61-68,共8页
The influence of short hairpin RNA(shRNA)-mediated osteopontin(OPN)gene silencing on the proliferation and invasion of human renal cancer ACHN cells was investigated.Four types of OPN shRNA recombinant plasmids were c... The influence of short hairpin RNA(shRNA)-mediated osteopontin(OPN)gene silencing on the proliferation and invasion of human renal cancer ACHN cells was investigated.Four types of OPN shRNA recombinant plasmids were constructed and RT-PCR assays were used to screen the most highly functional shRNA recombinant plasmids,which were transferred into the cultured ACHN cells by LipofectamineTM 2000.The cells transfected by shRNA expression vectors(ACHN/OPN)were visualized under an inverted microscope and screened... 展开更多
关键词 OSTEOPONTIN short hairpin RNA RNA interference human renal cancer cells
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Antitumor and antiangiogenic activities of anti-vascular endothelial growth factor hairpin ribozyme in human hepatocellular carcinoma cell cultures and xenografts 被引量:2
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作者 Li-Hua Li Zi-Jian Guo +5 位作者 Ling-Ling Yan Ji-Cheng Yang Yu-Feng Xie Wei-Hua Sheng Zhao-Hui Huang Xue-Hao Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第47期6425-6432,共8页
AIM: To study the effectiveness and mechanisms of anti-human vascular endothelial growth factor (hVEGF) hairpin ribozyme on angiogenesis,oncogenicity and tumor growth in a hepatocarcinoma cell line and a xenografted m... AIM: To study the effectiveness and mechanisms of anti-human vascular endothelial growth factor (hVEGF) hairpin ribozyme on angiogenesis,oncogenicity and tumor growth in a hepatocarcinoma cell line and a xenografted model. METHODS: The artificial anti-hVEGF hairpin ribozyme was transfected into hepatocarcinoma cell line SMMC-7721 and,subsequently,polymerase chain reaction (PCR) and reverse transcription polymerase chain reaction (RT-PCR) were performed to confirm the ribozyme gene integration and transcription. To determine the effects of ribozyme ,VEGF expression was detected by semiquantitative RT-PCR and enzyme liked immunosorbent assay (ELISA). MTT assay was carried out to measure the cell proliferation. Furthermore,the transfected and control cells were inoculated into nude mice respectively,the growth of cells in nude mice and angiogenesis were observed. RESULTS: VEGF expression was down-regulated sharply by ribozyme in transfected SMMC-7721 cells and xenografted tumor. Compared to the control group,the transfected cells grew slower in cell cultures and xenografts,and the xenograft formation was delayed as well. In addition,the microvessel density of the xenografted tumor was obviously declined in the transfected group. As demonstratedby microscopy,reduction of VEGF production induced by ribozyme resulted in a significantly higher cell differentiation and less proliferation vigor in xenografted tumor. CONCLUSION: Anti-hVEGF hairpin ribozyme can effectively inhibit VEGF expression and growth of hepatocarcinoma in vitro and in vivo. VEGF is functionally related to cell proliferation,differentiation and tumori-genesis in hepatocarcinoma. 展开更多
关键词 Vascular endothelial growth factor Angiogenesis hairpin ribozyme HEPATOCARCINOMA Gene therapy
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Complement factor B knockdown by short hairpin RNA inhibits laser-induced choroidal neovascularization in rats 被引量:1
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作者 Xin Wang Qing-Li Shang +3 位作者 Jing-Xue Ma Shu-Xia Liu Cai-Xia Wang Cheng Ma 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期382-389,共8页
AIM:To evaluate whether recombinant complement factor B(CFB)short hairpin RNA(sh RNA)reduces laserinduced choroidal neovascularization(CNV)in rats.METHODS:Laser-induced rat CNV model was established,and then the anima... AIM:To evaluate whether recombinant complement factor B(CFB)short hairpin RNA(sh RNA)reduces laserinduced choroidal neovascularization(CNV)in rats.METHODS:Laser-induced rat CNV model was established,and then the animals underwent fundus fluorescence angiography(FFA)and hematoxylin and eosin(HE)staining.On day 3 and 7 after photocoagulation,the expression of CFB and membrane attack complex(MAC)was detected by immunhischemistry.A recombinant CFBsh RNA plasmid was constructed.CFB and scrambled sh RNA plasmids were intravenous injected into rats via the tail vein on the day of laser treatment,respectively.On day 7,the incidence of CNV was determined by FFA,and the expression of CFB and vascular endothelial growth factor(VEGF)in retinal pigment epithelium(RPE)/choroidal tissues was detected by immunhischemistry,Western blot and/or semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR)in CFB and scrambled sh RNA groups.The possible adverse effects of CFB-sh RNA injection were assessed by transmission electron microscopy and electroretinography.RESULTS:FFA and HE results indicated that a laserinduced rat CNV model was successfully established on day 7 after photocoagulation.The expression of CFB and MAC was extremely weak in normal retina and choroid,and increased on day 3 after photocoagulation.However,it started to reduce on day 7.CFB sh RNA plasmid was successfully constructed and induced CFB knockdown in the retinal and choroidal tissues.FFA showed CFB knockdown significantly inhibited incidence of CNV in rats.Moreover,CFB knockdown significantly inhibited the expression of VEGF in RPE/choroidal tissues.CFB sh RNA caused no obvious side effects in eyes.CONCLUSION:CFB knockdown significantly inhibits the formation and development of CNV in vivo through reducing the expression of VEGF,which is a potential therapy target.The alternative pathway of complement activation plays an important role in CNV formation. 展开更多
关键词 choroidal NEOVASCULARIZATION COMPLEMENT FACTOR B short hairpin RNA membrane attack complex vascular ENDOTHELIAL growth FACTOR
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Lentivirus-mediated short hairpin RNA interference of CENPK inhibits growth of colorectal cancer cells with overexpression of Cullin 4A 被引量:2
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作者 Xian Li Yi-Ru Han +6 位作者 Xuefeng Xuefeng Yong-Xiang Ma Guo-Sheng Xing Zhi-Wen Yang Zhen Zhang Lin Shi Xin-Lin Wu 《World Journal of Gastroenterology》 SCIE CAS 2022年第37期5420-5443,共24页
BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors worldwide.The identification of novel diagnostic and prognostic biomarkers for CRC is a key research imperative.Immunohistochemical analysis ... BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors worldwide.The identification of novel diagnostic and prognostic biomarkers for CRC is a key research imperative.Immunohistochemical analysis has revealed high expression of centromere protein K(CENPK)in CRC.However,the role of CENPK in the progression of CRC is not well characterized.AIM To evaluate the effects of knockdown of CENPK and overexpression of Cullin 4A(CUL4A)in RKO and HCT116 cells.METHODS Human colon cancer samples were collected and tested using a human gene expression chip.We identified CENPK as a potential oncogene for CRC based on bioinformatics analysis.In vitro experiments verified the function of this gene.We investigated the expression of CENPK in RKO and HCT116 cells using quantitative polymerase chain reaction(qPCR),western blot,and flow cytometry.The effect of short hairpin RNA(shRNA)virus-infected RKO cells on tumor growth was evaluated in vivo using quantitative analysis of fluorescence imaging.To evaluate the effects of knockdown of CENPK and overexpression of CUL4A in RKO and HCT116 cells,we performed a series of in vitro experiments,using qPCR,western blot,MTT assay,and flow cytometry.RESULTS We demonstrated overexpression of CENPK in human colon cancer samples.CENPK was an independent risk factor in patients with CRC.The downstream genes FBX32,CUL4A,and Yesassociated protein isoform 1 were examined to evaluate the regulatory action of CENPK in RKO cells.Significantly delayed xenograft tumor emergence,slower growth rate,and lower final tumor weight and volume were observed in the CENPK short hairpin RNA virus infected group compared with the CENPK negative control group.The CENPK gene interference inhibited the proliferation of RKO cells in vitro and in vivo.The lentivirus-mediated shRNA interference of CENPK inhibited the proliferation of RKO and HCT116 colon cancer cells,with overexpression of the CUL4A.CONCLUSION We indicated a potential role of CENPK in promoting tumor proliferation,and it may be a novel diagnostic and prognostic biomarker for CRC. 展开更多
关键词 Colorectal cancer Centromere protein K Bioinformatics analysis Lentivirus-mediated short hairpin RNA interference Cullin 4A
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Advanced high-pressure plasma diagnostics with hairpin resonator probe surrounded by film and sheath 被引量:1
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作者 徐金洲 石建军 +3 位作者 张菁 张琪 中村圭二 菅井秀郎 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期387-393,共7页
The hairpin probe using microwave resonance in plasma is applicable to high pressure 1.33 ×10^3-1.01×10^5 Pa)) as developed recently. In this work, an analytic model of the hairpin resonator probe surround... The hairpin probe using microwave resonance in plasma is applicable to high pressure 1.33 ×10^3-1.01×10^5 Pa)) as developed recently. In this work, an analytic model of the hairpin resonator probe surrounded by a thin dielectric layer and a sheath layer is proposed. The correction factor due to these surroundings is analytically found and confirmed by electromagnetic field finite difference time domain simulation, thus enabling the accurate measurement of electron density in a high-pressure non-equilibrium uniform discharge. 展开更多
关键词 hairpin resonator probe simulation high-pressure plasma transmission line model
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Characteristic plume morphologies of atmospheric Ar and He plasma jets excited by a pulsed microwave hairpin resonator 被引量:1
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作者 Zhao-Quan Chen Ben-Kuan Zhou +7 位作者 Huang Zhang Ling-Li Hong Chang-Lin Zou Ping Li Wei-Dong Zhao Xiao-Dong Liu Olga Stepanova A A Kudryavtsev 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期355-364,共10页
Different discharge morphologies in atmospheric Ar and He plasmas are excited by using a pulsed microwave hairpin resonator.Ar plasmas form an arched plasma plume at the opened end of the hairpin,whereas He plumes gen... Different discharge morphologies in atmospheric Ar and He plasmas are excited by using a pulsed microwave hairpin resonator.Ar plasmas form an arched plasma plume at the opened end of the hairpin,whereas He plumes generate only a contracted plasmas in between both tips of metal electrodes.Despite this different point,their discharge processes have three similar characteristics:(i)the ionization occurs at the main electrode firstly and then develops to the slave electrode,(ii)during the shrinking stage the middle domain of the discharge channels disappears at last,and(iii)even at zero power input(in between pulses)a weak light region always exists in the discharge channels.Both experimental results and electromagnetic simulations suggest that the discharge is resonantly excited by the local enhanced electric fields.In addition,Ar ionization and excitation energies are lower than those of He,the effect of Ar gas flow is far greater than that of He gas,and the contribution of accelerated electrons only locates at the domain with the strongest electric fields.These reasons could be used to interpret the different characteristic plume morphologies of the proposed atmospheric Ar and He plasmas. 展开更多
关键词 atmospheric pressure plasma jet pulsed microwave discharge surface plasmon polaritons hairpin resonant discharge
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Small hairpin RNA against Bcl-2 increases MTX-induced apoptosis in Raji cells 被引量:1
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作者 Baoying Fang Dongmei He Yuan Zhang Li Chen 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第12期709-712,共4页
Objective:The aim of this study was to study the effect of Bcl-2 small hairpin RNA(shRNA) enhancing methotrexate(MTX)-induced apoptosis of Raji cells.Methods:Expression plasmid with Bcl-2 shRNA was transfected into Ra... Objective:The aim of this study was to study the effect of Bcl-2 small hairpin RNA(shRNA) enhancing methotrexate(MTX)-induced apoptosis of Raji cells.Methods:Expression plasmid with Bcl-2 shRNA was transfected into Raji cells by Lipofectmine 2000 and then treated with MTX.At 48 h of transfection,the expression level of Bcl-2 mRNA and protein was evaluated by RT-PCR and immunofluorescence.MTT assay was used to analyze cell proliferation at 24,48 and 72 h.Apoptosis was detected by Giemsa staining and flow cytometric cell cycle analysis.Results:After transfection with Bcl-2 shRNA,the expression levels of Bcl-2 mRNA and protein in Raji cells decreased(P < 0.05).Using Giemsa staining,cells transfected with Bcl-2 shRNA combined with MTX at 48 h displayed changes of apoptosis.MTX significantly inhibited the growth of cells after transfected with Bcl-2 shRNA(P < 0.05).Apoptotic rates of the Raji cells treated with Bcl-2 shRNA combined with MTX significantly increased(P < 0.05),compared with either control shRNA/MTX combination or MTX-treatment cells alone.Conclusion:Our results suggest the shRNA against Bcl-2 mRNA could increase MTX-induced apoptosis of Raji cells. 展开更多
关键词 BCL-2 small hairpin RNA (shRNA) Raji cells APOPTOSIS methotrexate (MTX)
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蛋白质中较频繁发生的β发夹结构(β—Hairpins)模式──蛋白质超二级结构(MOTIF)研究(Ⅲ) 被引量:1
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作者 孙之荣 《生物物理学报》 CSCD 北大核心 1994年第4期665-670,共6页
分析了240个分辨率在2.5A以上的高精度蛋白结构,研究了α螺旋和β折叠的连接短肽中的β发夹结构模式。首先对较频繁发生的超二级结构组中的E—loop—E[1](即β回折结构-βTurn)进行了分析,对每一种β回折结构... 分析了240个分辨率在2.5A以上的高精度蛋白结构,研究了α螺旋和β折叠的连接短肽中的β发夹结构模式。首先对较频繁发生的超二级结构组中的E—loop—E[1](即β回折结构-βTurn)进行了分析,对每一种β回折结构的氢键长度进行了计算,然后将其模型化。在对β发夹模型化的分析中,同时考虑了连接短肽的长度和氢键模式两个因素。找出了在240个蛋白样本库中较常发生的β发夹结构的模式。该结果对结构比较模型、X衍射晶体结构的解析,以及β发夹结构的预测有一定意义。 展开更多
关键词 连裂短肽 Α螺旋 Β折叠 β发夹结构 蛋白
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Hairpin扁线电机定子工艺方法比较分析 被引量:1
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作者 曾凡林 《机械设计与制造工程》 2021年第7期117-121,共5页
驱动电机定子绕组的发展趋势是采用扁平线,发卡式(Hairpin)结构是目前国内外的主流设计方案。基于多年的项目经验积累,重点介绍了Hairpin定子制造过程中的铜线去漆皮、线成型、扩口、扭头及焊接工艺,对不同的工艺实现方法加以对比分析,... 驱动电机定子绕组的发展趋势是采用扁平线,发卡式(Hairpin)结构是目前国内外的主流设计方案。基于多年的项目经验积累,重点介绍了Hairpin定子制造过程中的铜线去漆皮、线成型、扩口、扭头及焊接工艺,对不同的工艺实现方法加以对比分析,并给出了推荐的工艺方法。 展开更多
关键词 扁线电机 hairpin制造工艺 工艺方法
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基于NAT server和NAT Hairpin技术的网站服务器安全加固设计
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作者 徐洪峰 陶志勇 《长沙民政职业技术学院学报》 2021年第2期127-130,共4页
针对日益突出的攻击问题,提出了一种网站服务器安全加固的解决方案。方案结合了NAT server和NAT hairpin技术,隐藏了服务器的真实IP,避免受到内、外网用户的攻击,使服务器的安全得到加固。为了验证方案的可行性,利用HCL模拟器对设计理... 针对日益突出的攻击问题,提出了一种网站服务器安全加固的解决方案。方案结合了NAT server和NAT hairpin技术,隐藏了服务器的真实IP,避免受到内、外网用户的攻击,使服务器的安全得到加固。为了验证方案的可行性,利用HCL模拟器对设计理念进行了仿真实验。实验结果表明,方案能够隐藏服务器的真实地址信息,且能确保服务器为内、外网用户提供正常的访问服务,是一种有效的解决方案。 展开更多
关键词 网络安全 NAT server NAT hairpin
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