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Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma
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作者 XINFENG ZHANG SHUANG LI +8 位作者 MEIRU SONG YUE CHEN LIANGZHENG CHANG ZHERUI LIU HONGYUAN DAI YUTAO WANG GANGQI YANG YUN JIANG YINYING LU 《Oncology Research》 SCIE 2024年第4期679-690,共12页
Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expr... Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs. 展开更多
关键词 Hepatocellular carcinoma(HCC) Focal adhesion kinase(FAK) Proteolytic targeting chimera technology(PROTAC) Epithelial-mesenchymal transformation(EMT) METASTASIS
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“Rigid-elastic chimera” pore skeleton model and overpressure porosity measurement method for shale: A case study of the deep overpressure siliceous shale of Silurian Longmaxi Formation in southern Sichuan Basin, SW China
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作者 SHI Qiang CHEN Peng 《Petroleum Exploration and Development》 2023年第1期125-137,共13页
Based on analysis of pore features and pore skeleton composition of shale,a“rigid elastic chimeric”pore skeleton model of shale gas reservoir was built.Pore deformation mechanisms leading to increase of shale porosi... Based on analysis of pore features and pore skeleton composition of shale,a“rigid elastic chimeric”pore skeleton model of shale gas reservoir was built.Pore deformation mechanisms leading to increase of shale porosity due to the pore skeleton deformation under overpressure were sorted out through analysis of stress on the shale pore and skeleton.After reviewing the difficulties and defects of existent porosity measurement methods,a dynamic deformed porosity measurement method was worked out and used to measure the porosity of overpressure Silurian Longmaxi Formation shale under real formation conditions in southern Sichuan Basin.The results show:(1)The shale reservoir is a mixture of inorganic rock particles and organic matter,which contains inorganic pores supported by rigid skeleton particles and organic pores supported by elastic-plastic particles,and thus has a special“rigid elastic chimeric”pore structure.(2)Under the action of formation overpressure,the inorganic pores have tiny changes that can be assumed that they don’t change in porosity,while the organic pores may have large deformation due to skeleton compression,leading to the increase of radius,connectivity and ultimately porosity of these pores.(3)The“dynamic”deformation porosity measurement method combining high injection pressure helium porosity measurement and kerosene porosity measurement method under ultra-high variable pressure can accurately measure porosity of unconnected micro-pores under normal pressure conditions,and also the porosity increment caused by plastic skeleton compression deformation.(4)The pore deformation mechanism of shale may result in the"abnormal"phenomenon that the shale under formation conditions has higher porosity than that under normal pressure,so the overpressure shale reservoir is not necessarily“ultra-low in porosity”,and can have porosity over 10%.Application of this method in Well L210 in southern Sichuan has confirmed its practicality and reliability. 展开更多
关键词 shale gas “rigid-elastic chimera”pore model “dynamic”deformation porosity deep shale layers Silurian Longmaxi Formation Sichuan Basin
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基于Chimera网格的固定床反应器内局部流动模拟 被引量:7
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作者 郭雪岩 戴韧 王宏光 《化工学报》 EI CAS CSCD 北大核心 2008年第9期2214-2219,共6页
采用基于三维Chimera网格的有限体积方法对球形颗粒随机填充的固定床内部小Reynolds数(9~50)下的局部流动进行了数值模拟。为了考察固定床内局部流动特点,本文模拟的固定床反应器的填充颗粒的数目较大,分别为120和500,直径比(固定床内... 采用基于三维Chimera网格的有限体积方法对球形颗粒随机填充的固定床内部小Reynolds数(9~50)下的局部流动进行了数值模拟。为了考察固定床内局部流动特点,本文模拟的固定床反应器的填充颗粒的数目较大,分别为120和500,直径比(固定床内径与填充颗粒直径之比)分别为7和10。由于计算量巨大,采用了基于PVM的分布式并行计算。模拟结果提供了固定床内局部流动的详细流场信息,显示了流动的不均匀性、壁面效应和沟流的存在。为固定床内进一步的流动与传热及反应耦合研究奠定了基础。 展开更多
关键词 固定床 数值模拟 chimera网格 并行计算 局部流动
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介绍一款优秀的分子图形软件Chimera 被引量:3
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作者 仝艳 李晓晓 李晓飞 《化工时刊》 CAS 2011年第10期47-48,共2页
为提高信息技术在化学科研教育中的应用,介绍了一款名为UCSF chimera的优秀的分子图形软件,其自由的可视化功能及其他附属工具使用方便,在生物、医药、化学的科研、教育等方面都有着广泛的用途。
关键词 chimera 多媒体 蛋白质 图形软件
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填充床流动求解与基于Chimera网格的分布式并行计算
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作者 郭雪岩 宋步云 杨帆 《能源研究与信息》 2012年第3期165-170,共6页
填充床是一种常见的化学和生化反应器。由于内部结构的复杂性,填充床的局部流动求解一直是个颇有挑战性的问题。传统的填充床数值模拟是在CFD软件Fluent的平台上,采用非结构化网格求解。采用非结构网格求解存在网格生成困难,网格数目过... 填充床是一种常见的化学和生化反应器。由于内部结构的复杂性,填充床的局部流动求解一直是个颇有挑战性的问题。传统的填充床数值模拟是在CFD软件Fluent的平台上,采用非结构化网格求解。采用非结构网格求解存在网格生成困难,网格数目过多以及计算时间长等问题。Chimera网格的应用大大减少了填充床网格的数目及网格生成的难度。PVM分布式并行计算与Chimera网格的结合,使填充床的求解效率得到很大的提高。通过对两种方法在计算使用时间、内存使用量及计算结果的具体比较,阐述了Chimera网格结合PVM分布式并行计算在填充床流动求解中的优势。 展开更多
关键词 chimera网格 分布式并行计算 填充床 复杂流动
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Germline competence of mouse ES and iPS cell lines: Chimera technologies and genetic background 被引量:1
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作者 Ana Claudia Carstea Melinda K Pirity Andras Dinnyes 《World Journal of Stem Cells》 SCIE CAS 2009年第1期22-29,共8页
In mice,gene targeting by homologous recombination continues to play an essential role in the understanding of functional genomics.This strategy allows precise location of the site of transgene integration and is most... In mice,gene targeting by homologous recombination continues to play an essential role in the understanding of functional genomics.This strategy allows precise location of the site of transgene integration and is most commonly used to ablate gene expression("knock-out"),or to introduce mutant or modified alleles at the locus of interest("knock-in").The efficacy of producing live,transgenic mice challenges our understanding of this complex process,and of the factors which influence germline competence of embryonic stem cell lines.Increasingly,evidence indicates that culture conditions and in vitro manipulation can affect the germline-competence of Embryonic Stem cell(ES cell) lines by accumulation of chromosome abnormalities and/or epigenetic alterations of the ES cell genome. The effectiveness of ES cell derivation is greatly strain-dependent and it may also influence the germline transmission capability.Recent technical improvements in the production of germline chimeras have been focused on means of generating ES cells lines with a higher germline potential.There are a number of options for generating chimeras from ES cells (ES chimera mice);however,each method has its advantages and disadvantages.Recent developments in induced pluripotent stem(iPS)cell technology have opened new avenues for generation of animals from genetically modified somatic cells by means of chimera technologies.The aim of this review is to give a brief account of how the factors mentioned above are influencing the germline transmission capacity and the developmental potential of mouse pluripotent stem cell lines.The most recent methods for generating specifically ES and iPS chimera mice,including the advantages and disadvantages of each method are also discussed. 展开更多
关键词 chimeraS Transgenic Embryonic STEM CELLS Epigenetic changes GERMLINE COMPETENCE Induced pluripotent STEM CELLS
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Proteolysis targeting chimera technology:a novel strategy for treating diseases of the central nervous system 被引量:1
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作者 Ke Ma Xiao-Xiao Han +1 位作者 Xiao-Ming Yang Song-Lin Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第10期1944-1949,共6页
Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are lacking.Proteolysis targeting ... Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are lacking.Proteolysis targeting chimera(PROTAC)technology is a novel strategy to solve this problem.PROTAC technology uses the ubiquitin-protease system to eliminate mutated,denatured,and harmful proteins in cells.It can be reused,and utilizes the protein destruction mechanism of the cells,thus making up for the deficiencies of traditional protein degradation methods.It can effectively target and degrade proteins,including proteins that are difficult to identify and bind.Therefore,it has extremely important implications for drug development and the treatment of neurological diseases.At present,the targeted degradation of mutant BTK,mHTT,Tau,EGFR,and other proteins using PROTAC technology is gaining attention.It is expected that corresponding treatment of nervous system diseases can be achieved.This review first focuses on the recent developments in PROTAC technology in terms of protein degradation,drug production,and treatment of central nervous system diseases,and then discusses its limitations.This review will provide a brief overview of the recent application of PROTAC technology in the treatment of central nervous system diseases. 展开更多
关键词 Alzheimer’s disease disease treatment drug development Huntington’s disease proteolysis targeting chimera stroke targeted degradation
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Rotor wake capture improvement based on high-order spatially accurate schemes and chimera grids
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作者 徐丽 翁培奋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第12期1565-1576,共12页
A high-order upwind scheme has been developed to capture the vortex wake of a helicopter rotor in the hover based on chimera grids. In this paper, an improved fifth-order weighted essentially non-oscillatory (WENO) sc... A high-order upwind scheme has been developed to capture the vortex wake of a helicopter rotor in the hover based on chimera grids. In this paper, an improved fifth-order weighted essentially non-oscillatory (WENO) scheme is adopted to interpolate the higher-order left and right states across a cell interface with the Roe Riemann solver updating inviscid flux, and is compared with the monotone upwind scheme for scalar conservation laws (MUSCL). For profitably capturing the wake and enforcing the period boundary condition, the computation regions of flows are discretized by using the struc- tured chimera grids composed of a fine rotor grid and a cylindrical background grid. In the background grid, the mesh cells located in the wake regions are refined after the so- lution reaches the approximate convergence. Considering the interpolation characteristic of the WENO scheme, three layers of the hole boundary and the interpolation boundary are searched. The performance of the schemes is investigated in a transonic flow and a subsonic flow around the hovering rotor. The results reveal that the present approach has great capabilities in capturing the vortex wake with high resolution, and the WENO scheme has much lower numerical dissipation in comparison with the MUSCL scheme. 展开更多
关键词 hovering rotor vortex wake Navier-Stokes equation chimera grid weighted essentially non-oscillatory (WENO) scheme
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Controlling chaos and supressing chimeras in a fractional-order discrete phase-locked loop using impulse control
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作者 Karthikeyan Rajagopal Anitha Karthikeyan Balamurali Ramakrishnan 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期63-73,共11页
A fractional-order difference equation model of a third-order discrete phase-locked loop(FODPLL) is discussed and the dynamical behavior of the model is demonstrated using bifurcation plots and a basin of attraction. ... A fractional-order difference equation model of a third-order discrete phase-locked loop(FODPLL) is discussed and the dynamical behavior of the model is demonstrated using bifurcation plots and a basin of attraction. We show a narrow region of loop gain where the FODPLL exhibits quasi-periodic oscillations, which were not identified in the integer-order model. We propose a simple impulse control algorithm to suppress chaos and discuss the effect of the control step. A network of FODPLL oscillators is constructed and investigated for synchronization behavior. We show the existence of chimera states while transiting from an asynchronous to a synchronous state. The same impulse control method is applied to a lattice array of FODPLL, and the chimera states are then synchronized using the impulse control algorithm. We show that the lower control steps can achieve better control over the higher control steps. 展开更多
关键词 discrete Josephson junction fractional order chaos impulse control chimera
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Chaperone-mediated autophagy targeting chimeras (CMATAC) forthe degradation of ERα in breast cancer
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作者 JUN ZHANG YEHONG HUANG +2 位作者 WENZHUO LIU LULU LI LIMING CHEN 《BIOCELL》 SCIE 2020年第4期591-595,共5页
Estrogen receptor alpha(ERα/ESR1)is overexpressed in over half of all breast cancers and is considered a valuable therapeutic target in ERαpositive breast cancer.Here,we designed a membrane-permeant Chaperonemediate... Estrogen receptor alpha(ERα/ESR1)is overexpressed in over half of all breast cancers and is considered a valuable therapeutic target in ERαpositive breast cancer.Here,we designed a membrane-permeant Chaperonemediated Autophagy Targeting Chimeras(CMATAC)peptide to knockdown endogenous ERαprotein through chaperone-mediated autophagy.The peptide contains a cell membrane-penetrating peptide(TAT)that allows the peptide to by-pass the plasma membrane,anαI peptide as a protein-binding peptide(PBD)that binds specifically to ERα,and CMA-targeting peptide(CTM)that targeting chaperone-mediated autophagy.We validated that ERαtargeting peptide was able to target and degrade ERαto reduce the viability of ERαpositive breast cancer cells.Taken together,our studies provided a new method to reduce the level of intracellular ERαprotein via CMATAC,and thus may provide a new strategy for the treatment of ERαpositive breast cancer. 展开更多
关键词 Chaperone-mediated AUTOPHAGY TARGETING chimeraS (CMATAC) Breast cancer Peptide ERΑ
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一种基于Chimera软件的分子动力学模拟方法
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作者 马学婧 李俊甫 +3 位作者 宋立立 张兆英 王悦 孙琳琳 《科学技术创新》 2021年第13期61-63,共3页
Chimera是用于分子结构和相关数据的交互式可视化和分析程序,可实现的功能有密度图,轨迹和序列比对等。然而,目前对于其在分子动力学模拟方面的应用还没有详细的阐述。因此,本文拟详细介绍应用Chimera软件进行分子动力学模拟的流程,这... Chimera是用于分子结构和相关数据的交互式可视化和分析程序,可实现的功能有密度图,轨迹和序列比对等。然而,目前对于其在分子动力学模拟方面的应用还没有详细的阐述。因此,本文拟详细介绍应用Chimera软件进行分子动力学模拟的流程,这将促进其在生物、医药、化学的科研、教育等方面的应用进而推动这些领域的发展。 展开更多
关键词 chimera 图形软件 蛋白质 分子动力学模拟
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The Parody of Plots in John Barth's Chimera
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作者 谢昕烨 《海外英语》 2019年第5期201-201,共1页
John Barth uses a lot of parody in Chimera,such as plots,characters,etc.This article will compare the plot between Chimera and the originals,to interpret the imitation and mockery of parody.
关键词 PARODY chimera PLOT
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The Parody of Characters in John Barth’s Chimera
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作者 谢昕烨 《海外英语》 2019年第17期199-200,共2页
John Barth uses a lot of parody in Chimera,such as characters,story background,etc.From the analysis of character parody,we can feel the timeliness and reality of that period.
关键词 PARODY chimera CHARACTERS
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Four-cluster chimera state in non-locally coupled phase oscillator systems with an external potential 被引量:2
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作者 朱云 郑志刚 杨俊忠 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期169-175,共7页
Dynamics of a one-dimensional array of non-locally coupled Kuramoto phase oscillators with an external potential is studied.A four-cluster chimera state is observed for the moderate strength of the external potential.... Dynamics of a one-dimensional array of non-locally coupled Kuramoto phase oscillators with an external potential is studied.A four-cluster chimera state is observed for the moderate strength of the external potential.Different from the clustered chimera states studied before,the instantaneous frequencies of the oscillators in a synchronized cluster are different in the presence of the external potential.As the strength of the external potential increases,a bifurcation from the two-cluster chimera state to the four-cluster chimera states can be found.These phenomena are well predicted analytically with the help of the Ott–Antonsen ansatz. 展开更多
关键词 本地振荡器 嵌合体 状态 非耦合 系统 相位 局部耦合
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Production of chicken chimeras by fusing blastodermal cells with electroporation
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作者 S.Aritomi N.Fujihara 《Asian Journal of Andrology》 SCIE CAS CSCD 2000年第4期271-275,共5页
Aim: To establish techniques for producing somatic and gennline chimeric chicken by transferring blastodennal cells fused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile un... Aim: To establish techniques for producing somatic and gennline chimeric chicken by transferring blastodennal cells fused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile unincubated white Leghom and Rhode Island red chicken eggs were fused with electroporation. The treated cell suspension was transferred to the recovery medium (DMEM containing 10% FBS) and was injected into the subgerminal cavity of recipient tmincubated embryos (stage X). Results: Of 177 recipient embryos injected with the fusing blastodermal cells, 6 (3.4%) survived to hatching. Somatic chimerism was examined in the melanocyte of the feather. The presence of feathers originating from the donor cell was observed in 1 bird (16.7%) out of the 6 hatched birds. After 21 days of incubation two birds out of five embryos were subjected to polymemse chain reaction (PCR) analysis for W-chromosome-specific DNA for each tissue. One bird possessed W-chromosome-specific DNA in the stomach, and the other exhibited the same DNA in the left and right gonads and other tissues, but not the stomach. Conclusion: Recipient embryo having electrofused blastodermal cells yields somatic and germline chimeric chickens more successfully.(Asian J Androl 2000 Dec;2:271-275) 展开更多
关键词 鸡胚层 胚层细胞溶解 电穿孔 嵌合体
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Spiral wave chimeras in populations of oscillators coupled to a slowly varying diffusive environment
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作者 Lei Yang Yuan He Bing-Wei Li 《Frontiers of physics》 SCIE CSCD 2023年第1期71-83,共13页
Chimera states are firstly discovered in nonlocally coupled oscillator systems.Such a nonlocal coupling arises typically as oscillators are coupled via an external environment whose characteristic time scaleτis so sm... Chimera states are firstly discovered in nonlocally coupled oscillator systems.Such a nonlocal coupling arises typically as oscillators are coupled via an external environment whose characteristic time scaleτis so small(i.e.,τ→0)that it could be eliminated adiabatically.Nevertheless,whether the chimera states still exist in the opposite situation(i.e.,τ≫1)is unknown.Here,by coupling large populations of Stuart–Landau oscillators to a diffusive environment,we demonstrate that spiral wave chimeras do exist in this oscillator-environment coupling system even whenτis very large.Various transitions such as from spiral wave chimeras to spiral waves or unstable spiral wave chimeras as functions of the system parameters are explored.A physical picture for explaining the formation of spiral wave chimeras is also provided.The existence of spiral wave chimeras is further confirmed in ensembles of FitzHugh–Nagumo oscillators with the similar oscillator-environment coupling mechanism.Our results provide an affirmative answer to the observation of spiral wave chimeras in populations of oscillators mediated via a slowly changing environment and give important hints to generate chimera patterns in both laboratory and realistic chemical or biological systems. 展开更多
关键词 spiral wave chimeras reaction-diffusion systems oscillator-environment coupling pattern formation
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A Proximity-Triggered Strategy toward Transferable Proteolysis Targeting Chimeras
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作者 Yuena Wang Rongtong Zhao +14 位作者 Chuan Wan Wei Kang Rui Wang Chengyao Chiang Xiaochun Guo Qi Chang Zhanfeng Hou Yuxin Ye Qinhong Luo Ziyuan Zhou Jianbo Liu Shuiming Li Dongyuan Wang Feng Yin Zigang Li 《CCS Chemistry》 CSCD 2023年第6期1433-1442,共10页
Over the past 20 years,great efforts have been invested in developing site-specific approaches to protein modification to dissect protein functions directly and accurately.Here,we report a proximitytriggered group tra... Over the past 20 years,great efforts have been invested in developing site-specific approaches to protein modification to dissect protein functions directly and accurately.Here,we report a proximitytriggered group transfer strategy from a sulfonium warhead to a Cysteine(Cys)residue of the target protein.With a guiding ligand,cargoes could be transferred selectively from a sulfonium center onto the Cys residue in the vicinity of their binding interface.The successful thalidomide transfer of sulfonium 1-X could be applied intracellularly for epidermal growth factor receptor degradation,highlighting the potential of group transfer strategy as a suite of chemical biology studies,including cell imaging,protein profiling,and protein degradation by simply employing different transferrable groups. 展开更多
关键词 SULFONIUM protein covalent modification proteolysis targeting chimeras site-specific modification degradation
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45,X/47,XYY性发育异常一例并文献复习 被引量:1
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作者 田文艳 罗营 +4 位作者 李小燕 颜琪 薛凤霞 王颖梅 张慧英 《国际生殖健康/计划生育杂志》 CAS 2024年第1期11-16,共6页
45,X/47,XYY性发育异常是一种由于罕见的染色体异常导致的性发育异常疾病。报告1例收治的45,X/47,XYY嵌合型性发育异常患者,该患者主因原发性闭经并出现男性化表现就诊,具有特纳综合征(Turner syndrome,Turner综合征)的表现,腹腔镜探查... 45,X/47,XYY性发育异常是一种由于罕见的染色体异常导致的性发育异常疾病。报告1例收治的45,X/47,XYY嵌合型性发育异常患者,该患者主因原发性闭经并出现男性化表现就诊,具有特纳综合征(Turner syndrome,Turner综合征)的表现,腹腔镜探查显示一侧性腺为条索状,另一侧外观睾丸样,病理为卵睾型性腺,手术切除双侧附件并予人工周期治疗,有月经来潮。结合本例及检索到的文献报道的女性表型中因原发性闭经就诊的病例共11例,对该病的临床表现、诊断及治疗方式进行总结。女性表型45,X/47,XYY性发育异常患者临床表现多样,以Turner综合征表现合并男性化表现多见,应尽早发现并切除发育不良的性腺,防止性腺肿瘤的发生和男性化表现出现。术后进行长期激素替代治疗,同时注重患者精神心理的疏导。 展开更多
关键词 性发育障碍 嵌合体 性染色体畸变 性腺发育不全 混合性 泌尿生殖系统畸形 特纳综合征 激素替代疗法
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Generation of rat blood vasculature and hematopoietic cells in rat-mouse chimeras by blastocyst complementation 被引量:2
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作者 Xiaomin Wang Hui Shi +11 位作者 Juanjuan Zhou Qingjian Zou Quanjun Zhang Shixue Gou Pengfei Chen Lisha Mou Nana Fan Yangyang Suo Zhen Ouyang Chengdan Lai Quanmei Yan Liangxue Lai 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2020年第5期249-261,共13页
Interspecies chimera through blastocyst complementation could be an alternative approach to create human organs in animals by using human pluripotent stem cells.A mismatch of the major histocompatibility complex of va... Interspecies chimera through blastocyst complementation could be an alternative approach to create human organs in animals by using human pluripotent stem cells.A mismatch of the major histocompatibility complex of vascular endothelial cells between the human and host animal will cause graft rejection in the transplanted organs.Therefore,to achieve a transplantable organ in animals without rejection,creation of vascular endothelial cells derived from humans within the organ is necessary.In this study,to explore whether donor xeno-pluripotent stem cells can compensate for blood vasculature in host animals,we generated rat-mouse chimeras by injection of rat embryonic stem cells(rESCs)into mouse blastocysts with deficiency of Flk-1 protein,which is associated with endothelial and hematopoietic cell development.We found that rESCs could differentiate into vascular endothelial and hematopoietic cells in the rat-mouse chimeras.The whole yolk sac(YS)of Flk-1^EGFP/ECFP rat-mouse chimera was full of rat blood vasculature.Rat genes related to vascular endothelial cells,arteries,and veins,blood vessels formation process,as well as hematopoietic cells,were highly expressed in the YS.Our results suggested that rat vascular endothelial cells could undergo proliferation,migration,and self-assembly to form blood vasculature and that hematopoietic cells could differentiate into B cells,T cells,and myeloid cells in rat-mouse chimeras,which was able to rescue early embryonic lethality caused by Flk-1 deficiency in mouse. 展开更多
关键词 Blastocyst complementation Interspecies chimera Intraspecies chimera Flk-1 Vascular endothelial cell Hematopoietic cell
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An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver
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作者 Yiming Liang Guangning Li +3 位作者 Min Xu Junmin Zhao Feng Hao Hongbo Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期663-674,共12页
In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a... In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect.Firstly,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed.In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried out.The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation.Secondly,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy respectively.The intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters.Compared with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability error.The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application. 展开更多
关键词 Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid
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