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基于IP联合蛋白质组学探讨ENG互作蛋白在bEnd.3细胞中的作用
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作者 陈清杰 李奥迪 +4 位作者 季慧敏 孙艺瑄 蒋越 叶子奇 潘荣 《湖北科技学院学报(医学版)》 2024年第6期461-466,F0002,共7页
目的本研究拟筛选并验证在脑微血管内皮细胞(bEnd.3)中Endoglin(ENG)的互作蛋白及其作用。方法采用蛋白质组学和生物信息学技术鉴定并富集ENG互作蛋白,对这些互作蛋白进行亚细胞定位、GO功能注释、IPR注释和蛋白互作网络等分析。将以上... 目的本研究拟筛选并验证在脑微血管内皮细胞(bEnd.3)中Endoglin(ENG)的互作蛋白及其作用。方法采用蛋白质组学和生物信息学技术鉴定并富集ENG互作蛋白,对这些互作蛋白进行亚细胞定位、GO功能注释、IPR注释和蛋白互作网络等分析。将以上分析筛选出的ENG互作蛋白,采用免疫共沉淀(IP)实验、细胞免疫荧光(IF)和蛋白免疫印迹(WB)技术进行验证和对比,探究ENG互作蛋白在棕榈酸(PA)、基因沉默和过表达ENG处理bEnd.3细胞中的表达变化及作用。结果通过蛋白质组学分析,bEnd.3细胞中ENG互作蛋白在亚细胞定位分析中细胞骨架相关成分呈现出较高的占比;通过GO注释和IPR注释进一步发现,是细胞骨架中的中间纤维和微丝蛋白呈现较高的富集状态。ENG与细胞骨架蛋白互作热力图结果显示,与对照组相比,PA处理的bEnd.3细胞中微丝蛋白Filamin B(Flnb)数值显著降低。IP和IF结果显示,bEnd.3细胞中ENG与Flnb存在蛋白互作和共定位情况。WB结果显示,bEnd.3细胞在PA处理条件下,ENG和Flnb蛋白表达均下降;在ENG沉默条件下,Flnb蛋白随ENG表达的减少而降低;在ENG过表达条件下,Flnb蛋白随ENG表达的增加而升高。结论ENG互作蛋白广泛参与到多种相关的生物途径以及信号通路之中,ENG在bEnd.3细胞中与Flnb蛋白存在相互作用且二者具有共定位现象,ENG还能够调控PA处理的bEnd.3细胞Flnb蛋白表达水平。 展开更多
关键词 ENG Flnb 互作蛋白 bend.3 棕榈酸
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Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe 被引量:1
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作者 WEI Wen-bin YUAN Lin +1 位作者 ZHOU Jia-sheng LIU Zheng 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期221-232,共12页
Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which cau... Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole line.In this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical methods.Two types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,respectively.The hydraulic expansion and bending experiments of small-scale MLPs are conducted.In addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive side.In contrast,the liner of ALP remains intact without developing any wrinkling and collapse mode.In addition,a dedicated numerical framework and theoretical models were also established.It was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results. 展开更多
关键词 lined pipe bendING nonlinear ring theory BUCKLING PLASTICITY
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Effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on tensile and bending properties of high-Al-containing Mg alloys 被引量:1
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作者 Sumi Jo Gyo Myeong Lee +2 位作者 Jong Un Lee Young Min Kim Sung Hyuk Park 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期779-793,共15页
This study investigates the effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on the uniaxial tensile and three-point bending properties of extruded Mg alloys containing high Al contents.The ext... This study investigates the effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on the uniaxial tensile and three-point bending properties of extruded Mg alloys containing high Al contents.The extruded Mg–9Al–1Zn–0.3Mn(AZ91)alloy contains lamellar-structured Mg_(17)Al_(12)discontinuous precipitates along the grain boundaries,which are formed via static precipitation during natural air cooling.The extruded Mg–11Al–1Zn–0.3Mn(AZ111)alloy contains spherical Mg_(17)Al_(12)precipitates at the grain boundaries and inside the grains,which are formed via dynamic precipitation during extrusion.Due to inhomogeneous distribution of precipitates,the AZ111 alloy consists of two different precipitate regions:precipitate-rich region with numerous precipitates and finer grains and precipitate-scarce region with a few precipitates and coarser grains.The AZ111 alloy exhibits a higher tensile strength than the AZ91 alloy because its smaller grain size and more abundant precipitates result in stronger grain-boundary hardening and precipitation hardening effects,respectively.However,the tensile elongation of the AZ111 alloy is lower than that of the AZ91 alloy because the weak cohesion between the dynamic precipitates and the matrix facilitates the crack initiation and propagation.During bending,a macrocrack initiates on the outer surface of bending specimen in both alloys.The AZ111 alloy exhibits higher bending yield strength and lower failure bending strain than the AZ91 alloy.The bending specimens of the AZ91 alloy have similar bending formability,whereas those of the AZ111 alloy exhibit considerable differences in bending formability and crack propagation behavior,depending on the distribution and number density of precipitates in the specimen.In bending specimens of the AZ111 alloy,it is found that the failure bending strain(ε_(f,bending))is inversely proportional to the area fraction of precipitates in the outer zone of bending specimen(A_(ppt)),with a relationship ofε_(f,bending)=–0.1A_(ppt)+5.86. 展开更多
关键词 Mg–Al alloy EXTRUSION bendING Precipitation Microstructure
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基于p38MAPK-PPARγ/NF-κB信号通路探讨消肿止痛合剂对血管内皮细胞bEND-3凋亡的影响
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作者 朱克玉 宋渊 +4 位作者 梁旭东 沈稼轩 张团庄 乔靖 刘涛 《辽宁中医杂志》 CAS 北大核心 2024年第4期149-152,I0002,共5页
目的从细胞及信号通路层面探讨消肿止痛合剂对皮瓣缺血再灌注损伤中血管内皮细胞凋亡的影响。方法血管内皮细胞bEND-3培养。TNF-α体外细胞凋亡诱导模型建立并将细胞分为:p38MAPK抑制剂组、PPARγ抑制剂组、NF-κB抑制剂组、模型对照组... 目的从细胞及信号通路层面探讨消肿止痛合剂对皮瓣缺血再灌注损伤中血管内皮细胞凋亡的影响。方法血管内皮细胞bEND-3培养。TNF-α体外细胞凋亡诱导模型建立并将细胞分为:p38MAPK抑制剂组、PPARγ抑制剂组、NF-κB抑制剂组、模型对照组、空白组。微丝绿色荧光探针观察细胞骨架微丝。RT-PCR法检测血管内皮细胞bEND-3细胞中p38MAPK、PPARγ、IκBα、NF-κBmRNA的表达。结果空白组中p38MAPK、PPARγ、IκBα、NF-κB的表达量无明显差异,模型对照组中p38MAPK与NF-κB的表达量最高,与模型对照组相比,p38MAPK抑制剂组bEnd.3细胞中p38MAPK与NF-κB的表达被抑制,PPARγ、IκBα表达量升高(P<0.05);PPARγ抑制剂组中PPARγ、IκBα、NF-κB的表达被抑制,p38MAPK表达量升高(P<0.05),NF-κB抑制剂组中p38MAPK与NF-κB的表达被抑制,IκBα与PPARγ的表达量升高(P<0.05);与空白组相比,p38MAPK抑制剂组与NF-κB抑制剂组中p38MAPK、PPARγ、IκBα、NF-κB的表达量升高(P<0.05),PPARγ抑制剂组中p38MAPK与NF-κB表达量明显升高,PPARγ、IκBα表达被抑制(P<0.05)。结论消肿止痛合剂可抑制bEND-3细胞凋亡,其机制与影响可能与p38MAPK-PPARγ/NF-κB信号通路有关。 展开更多
关键词 消肿止痛合剂 bend-3细胞 信号通路 皮瓣
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Bending Failure Mode and Prediction Method of the Compressive Strain Capacity of A Submarine Pipeline with Dent Defects
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作者 HOU Fu-heng JIA Lu-sheng +3 位作者 CHEN Yan-fei ZHANG Qi ZHONG Rong-feng WANG Chun-sha 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期636-647,共12页
A dent is a common type of defects for submarine pipeline.For submarine pipelines,high hydrostatic pressure and internal pressure are the main loads.Once pipelines bend due to complex subsea conditions,the compression... A dent is a common type of defects for submarine pipeline.For submarine pipelines,high hydrostatic pressure and internal pressure are the main loads.Once pipelines bend due to complex subsea conditions,the compression strain capacity may be exceeded.Research into the local buckling failure and accurate prediction of the compressive strain capacity are important.A finite element model of a pipeline with a dent is established.Local buckling failure under a bending moment is investigated,and the compressive strain capacity is calculated.The effects of different parameters on pipeline local buckling are analyzed.The results show that the dent depth,external pressure and internal pressure lead to different local buckling failure modes of the pipeline.A higher internal pressure indicates a larger compressive strain capacity,and the opposite is true for external pressure.When the ratio of external pressure to collapse pressure of intact pipeline is greater than 0.1,the deeper the dent,the greater the compressive strain capacity of the pipeline.And as the ratio is less than 0.1,the opposite is true.On the basis of these results,a regression equation for predicting the compressive strain capacity of a dented submarine pipeline is proposed,which can be referred to during the integrity assessment of a submarine pipeline. 展开更多
关键词 submarine pipeline dent defect bending load local buckling compressive strain capacity
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Fabrication of lightweight 3D interpenetrated NiTi@Mg composite with superior bending properties
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作者 Yu-jing LIU Xiao-chun LIU +4 位作者 Kun-mao LI Xiang WU Sheng-feng ZHOU Wei LI Wen-cai ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第11期3569-3584,共16页
A NiTi@Mg interpenetrating phase composite with high strength and lightweight was prepared by additive manufacturing(AM)and infiltration technology,and the interface bonding,three-point bending properties and cyclic c... A NiTi@Mg interpenetrating phase composite with high strength and lightweight was prepared by additive manufacturing(AM)and infiltration technology,and the interface bonding,three-point bending properties and cyclic compressive properties of NiTi@Mg composites were investigated.The results show that the metallurgically bonded interface is formed at the NiTi/Mg interfaces.The bending strength and compressive strength of the NiTi@Mg composite are 2.5 and 1.7 times higher than those of the NiTi scaffold,respectively.During the bending deformation process,a large number of dislocations are observed to accumulate in the soft Mg area at the interface.Furthermore,the finite element model showed that the stress accumulation area,where the bending crack is initiated,is located at the interface of NiTi and Mg.The strengthening mechanism of NiTi@Mg composites is attributed to the twinning strengthening of Mg and heterogeneous structure strengthening. 展开更多
关键词 metal composites NiTi@Mg bending properties finite element simulation strengthening mechanism
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Discharge evolution law of debris flow based on a sharp bend physical modeling test
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作者 LU Ming SUN Hao +3 位作者 LIU Jinfeng Abrar HUSSAIN SHANG Yuqi FU Hang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1904-1915,共12页
For the basins with debris flow development,its channel terrain exhibits a tortuous shape,which significantly restricts the movement of debris flows and leads to severe erosion effects on the concave bank.Therefore,th... For the basins with debris flow development,its channel terrain exhibits a tortuous shape,which significantly restricts the movement of debris flows and leads to severe erosion effects on the concave bank.Therefore,this study aims to analyze the shear force of debris flows within the bend channel.We established the relationship between the shear force and bend curvature through laboratory experiments.Under the long-term erosion by debris flows,the curvature radius of bends gradually increases,however,when this increasing trend reaches an equilibrium state with the intensity of debris flow discharge,there will be no significant change in curvature radius.In general,the activity pattern and discharges of debris flows would remain relatively stable.Hence,we can infer the magnitude of debris flow discharges from the terrain parameters of the bend channel. 展开更多
关键词 Debris flow discharge Erosion effect bend channel Curvature radius
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Cryogenic springback of 2219-W aluminum alloy sheet through V-shaped bending
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作者 Xiao-bo FAN Qi-liang WANG +1 位作者 Fang-xing WU Xu-gang WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3185-3193,共9页
A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism w... A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism was elucidated through mechanical analyses and numerical simulations.The results indicated that the springback angle at cryogenic temperatures was greater than that at room temperature.The springback angle increased further as the temperature returned to ambient conditions,attributed to the combined effects of the “dual enhancement effect” and thermal expansion.Notably,a critical fillet radius made the springback angle zero for 90° V-shaped bending.The critical fillet radius at cryogenic temperatures was smaller than that at room temperature,owing to the influence of temperature variations on the bending moment ratio between the forward bending section at the fillet and the reverse bending section of the straight arm. 展开更多
关键词 2219-W aluminum alloy cryogenic forming V-shape bending SPRINGBACK critical fillet radius
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Analysis of deformation mechanisms in magnesium single crystals using a dedicated four-point bending tester
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作者 Yutaka Yoshida Rikuto Izawa Kenji Ohkubo 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1911-1917,共7页
In this study,we explored the deformation mechanisms of Mg single crystals using a combination of scanning electron microscopy and electron backscattered diffraction in conjunction with a dedicated four-point bending ... In this study,we explored the deformation mechanisms of Mg single crystals using a combination of scanning electron microscopy and electron backscattered diffraction in conjunction with a dedicated four-point bending tester.We prepared two single-crystal samples,oriented along the<1120>and<1010>directions,to assess the mechanisms of deformation when the initial basal slip was suppressed.In the<1120>sample,the primary{1012}twin(T1)was confirmed along the<1120>direction of the sample on the compression side with an increase in bending stress.In the<1010>sample,T1 and the secondary twin(T2)were confirmed to be along the<1120>direction,with an orientation of±60°with respect to the bending stress direction,and their direction matched with(0001)in T1 and T2.This result implies that crystallographically,the basal slip occurs readily.In addition,the<1010>sample showed the double twin in T1 on the compression side and the tertiary twin along the<1010>direction on the tension side.These results demonstrated that the maximum bending stress and displacement changed significantly under the bend loading because the deformation mechanisms were different for these single crystals.Therefore,the correlation between bending behavior and twin orientation was determined,which would be helpful for optimizing the bending properties of Mg-based materials. 展开更多
关键词 Four-point bending Magnesium single crystal TWINNING Basal slip Scanning electron microscopy Electron backscatter diffraction
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Bending strength degradation of a cantilever plate with surface energy due to partial debonding at the clamped boundary
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作者 Zhenliang HU Xueyang ZHANG Xianfang LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1573-1594,共22页
This paper investigates the bending fracture problem of a micro/nanoscale cantilever thin plate with surface energy,where the clamped boundary is partially debonded along the thickness direction.Some fundamental mecha... This paper investigates the bending fracture problem of a micro/nanoscale cantilever thin plate with surface energy,where the clamped boundary is partially debonded along the thickness direction.Some fundamental mechanical equations for the bending problem of micro/nanoscale plates are given by the Kirchhoff theory of thin plates,incorporating the Gurtin-Murdoch surface elasticity theory.For two typical cases of constant bending moment and uniform shear force in the debonded segment,the associated problems are reduced to two mixed boundary value problems.By solving the resulting mixed boundary value problems using the Fourier integral transform,a new type of singular integral equation with two Cauchy kernels is obtained for each case,and the exact solutions in terms of the fundamental functions are determined using the PoincareBertrand formula.Asymptotic elastic fields near the debonded tips including the bending moment,effective shear force,and bulk stress components exhibit the oscillatory singularity.The dependence relations among the singular fields,the material constants,and the plate's thickness are analyzed for partially debonded cantilever micro-plates.If surface energy is neglected,these results reduce the bending fracture of a macroscale partially debonded cantilever plate,which has not been previously reported. 展开更多
关键词 micro/nanoscale cantilever plate partially debonded bending fracture singular integral equation oscillatory singularity
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A Light and Simplified Branch Bending Method for Young Pear Trees
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作者 Jintao XU Longfei LI +3 位作者 Minghui JI Huan LIU Lijuan GAO Baofeng HAO 《Plant Diseases and Pests》 2024年第2期19-21,共3页
Aiming at high cost and low efficiency of conventional branch bending method in the modern intensive planting and labor-saving cultivation mode of young pear trees,this paper provides a new branch bending method with ... Aiming at high cost and low efficiency of conventional branch bending method in the modern intensive planting and labor-saving cultivation mode of young pear trees,this paper provides a new branch bending method with wide source of raw materials,cheap price and simple operation,which is also suitable for the management of low-age branches in the process of high grafting and upgrading of traditional big trees. 展开更多
关键词 Pear tree Light and simplified Branch bending METHOD
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The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-Walled Cantilever Channel Beam
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作者 David W. A. Rees Abdelraouf M. Sami Alsheikh 《World Journal of Mechanics》 2024年第5期73-96,共24页
Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers with x-axis symmetry. The flexural bending and shear that arise with applied axial torsion are each considered theoreticall... Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers with x-axis symmetry. The flexural bending and shear that arise with applied axial torsion are each considered theoretically and numerically in terms of two longitudinal axes of loading not coincident with the shear centre. In particular, the warping displacements, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its web centre. The stress conversions derived from each action are superimposed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established compared to previous results for each beam when loading is referred to a flexural axis through the shear centre. Within the net stress analysis is, it is shown how the constraint to free warping presented by the end fixing modifies the axial stress. The latter can be identified with the action of a ‘bimoment’ upon each thin-walled section. 展开更多
关键词 Thin-Aluminium Channels Cantilever Beam bending Shear Torsion WARPING BIMOMENT Flexural Axis Centre of Twist CENTROID Shear Centre Torsional Stiffness Constrained Stress
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Prediction of seismic-induced bending moment and lateral displacement in closed and open-ended pipe piles:A genetic programming approach
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作者 Laith Sadik Duaa Al-Jeznawi +2 位作者 Saif Alzabeebee Musab A.Q.Al-Janabi Suraparb Keawsawasvong 《Artificial Intelligence in Geosciences》 2024年第1期82-95,共14页
Ensuring the reliability of pipe pile designs under earthquake loading necessitates an accurate determination of lateral displacement and bending moment,typically achieved through complex numerical modeling to address... Ensuring the reliability of pipe pile designs under earthquake loading necessitates an accurate determination of lateral displacement and bending moment,typically achieved through complex numerical modeling to address the intricacies of soil-pile interaction.Despite recent advancements in machine learning techniques,there is a persistent need to establish data-driven models that can predict these parameters without using numerical simulations due to the difficulties in conducting correct numerical simulations and the need for constitutive modelling parameters that are not readily available.This research presents novel lateral displacement and bending moment predictive models for closed and open-ended pipe piles,employing a Genetic Programming(GP)approach.Utilizing a soil dataset extracted from existing literature,comprising 392 data points for both pile types embedded in cohesionless soil and subjected to earthquake loading,the study intentionally limited input parameters to three features to enhance model simplicity:Standard Penetration Test(SPT)corrected blow count(N60),Peak Ground Acceleration(PGA),and pile slenderness ratio(L/D).Model performance was assessed via coefficient of determination(R^(2)),Root Mean Squared Error(RMSE),and Mean Absolute Error(MAE),with R^(2) values ranging from 0.95 to 0.99 for the training set,and from 0.92 to 0.98 for the testing set,which indicate of high accuracy of prediction.Finally,the study concludes with a sensitivity analysis,evaluating the influence of each input parameter across different pile types. 展开更多
关键词 Genetic programming Pipe piles Lateral response bending moment Earthquake loading Standard penetration test Machine learning
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Defects detection in typical positions of bend pipes using low-frequency ultrasonic guided wave 被引量:1
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作者 罗更生 谭建平 +1 位作者 汪亮 许焰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3860-3867,共8页
In order to analyze the possibility of detecting defects in bend pipe using low-frequency ultrasonic guided wave, the propagation of T(0,1) mode and L(0,2) mode through straight-curved-straight pipe sections was studi... In order to analyze the possibility of detecting defects in bend pipe using low-frequency ultrasonic guided wave, the propagation of T(0,1) mode and L(0,2) mode through straight-curved-straight pipe sections was studied. FE(finite element) models of bend pipe without defects and those with defects were introduced to analyze energy distribution, mode transition and defect detection of ultrasonic guided wave. FE simulation results were validated by experiments of four different bend pipes with circumferential defects in different positions. It is shown that most energy of T(0,1) mode or L(0,2) mode focuses on extrados of bend but little passes through intrados of bend, and T(0,1) mode or L(0,2) mode is converted to other possible non-axisymmetric modes when propagating through the bend and the defect after bend respectively. Furthermore, L(0,2) mode is more sensitive to circumferential notch than T(0,1) mode. The results of this work are beneficial for practical testing of pipes. 展开更多
关键词 low-frequency ultrasonic guided wave bend pipe extrados of bend intrados of bend FE(finite element) simulation experimental investigation
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Analysis of bending mechanism in multi-scanning laser bending process based on plastic strain development
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作者 Wang Chao Wu Chunbiao +1 位作者 Xu Benlian Kim Jaewoong 《China Welding》 CAS 2022年第4期28-36,共9页
By using multi-pass straight-line scan strategies,a larger bending angle can be achieved.There is,however,a limited understanding of the variation in bending angle per pass during multi-pass under various process para... By using multi-pass straight-line scan strategies,a larger bending angle can be achieved.There is,however,a limited understanding of the variation in bending angle per pass during multi-pass under various process parameters.In multi-pass laser scanning,the bending angle cannot always linearly increase with scanning passes and this phenomenon can be observed mostly in low heat input.Strain hardening is the common explanation for this phenomenon.However,it could not explain why this bending angle reduction phenomenon occurs at low heat input scanning rather than at high heat input scanning.In this study,this phenomenon is discussed based on strain development in experiments and numerical simulation.The different growing mechanism of plastic strain is analyzed to reveal the effects of laser power and scanning velocity.Furthermore,the opposite bending trend that occurred at larger laser power is discussed in comparison to the plastic strain development.The study shows that relatively larger heat input below 6.7 J/mm can help to avoid the bending angle reduction phenomenon and the opposite bending trend is highly dependent on the larger laser power.For achieving the expected cumulative bending angle in multi-pass laser bending,it is recommended to decrease the scanning velocity at a relatively low laser power level while increase the scanning velocity at a high level of laser power. 展开更多
关键词 bending angle reduction phenomenon opposite bending trend multi-pass laser bending plastic strain development
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小鼠脑微血管内皮细胞株bEnd.3的细胞特征及基因表达谱分析 被引量:13
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作者 乐飞 张国平 +2 位作者 金惠铭 史连国 殷莲华 《中国病理生理杂志》 CAS CSCD 北大核心 2004年第8期1340-1344,共5页
目的 :对一种小鼠脑组织来源的血管内皮细胞株bEnd .3的主要细胞特征进行研究并做血管内皮细胞生物学功能基因芯片分析。方法 :利用倒置显微镜、扫描和透射电子显微镜观察细胞形态特征 ;免疫细胞化学法显示血管内皮细胞特异性表面标志 ;... 目的 :对一种小鼠脑组织来源的血管内皮细胞株bEnd .3的主要细胞特征进行研究并做血管内皮细胞生物学功能基因芯片分析。方法 :利用倒置显微镜、扫描和透射电子显微镜观察细胞形态特征 ;免疫细胞化学法显示血管内皮细胞特异性表面标志 ;ELISA定量检测PGE2 ;流式细胞术、MTT法研究增殖和凋亡、血管内皮细胞基因芯片研究正常培养bEnd 3基因表达谱。结果 :bEnd 3具备多种典型的微血管内皮细胞 (MVEC)特征 :细胞呈多边形或梭型、呈铺路石样生长 ;存在管腔样结构 (TLS)和毛细血管样网络 ,细胞表面有丰富的微绒毛 ;vW因子、CD34阳性 ;CD31、CD36、CD10 5等也有不同程度的表达 ;细胞高水平分泌前列腺素E2 (PGE2 ) ;多种与正常血管功能密切相关的基因也有不同程度的表达。结论 :bEnd .3保留了MVEC的基本特性 ,可用于心脑血管疾病。 展开更多
关键词 bend.3细胞 内皮 von WILLEBRAND因子 抗原 CD34 寡核苷酸序列分析
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Three-point bending behavior of aluminum foam sandwich with steel panel 被引量:7
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作者 祖国胤 卢日环 +4 位作者 李小兵 仲照阳 马幸江 韩明博 姚广春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2491-2495,共5页
Static three-point bending tests of aluminum foam sandwiches with glued steel panel were performed. The deformation and failure of sandwich structure with different thicknesses of panel and foam core were investigated... Static three-point bending tests of aluminum foam sandwiches with glued steel panel were performed. The deformation and failure of sandwich structure with different thicknesses of panel and foam core were investigated. The results indicate that the maximum bending load increases with the thickness of both steel panel and foam core. The failure of sandwich can be ascribed to the crush and shear damage of foam core and the delamination of glued interface at a large bending load, The crack on the foam wall developed in the melting foam procedure is the major factor for the failure of foam core. The sandwich structure with thick foam core and thin steel panel has the optimal specific bending strength. The maximum bending load of that with 8 mm panel and 50 mm foam core is 66.06 kN. 展开更多
关键词 aluminum foam sandwich three-point bending failure mode panel thickness
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CXCR4/SDF-1轴调节人肺腺癌PC-9细胞对Bends细胞血脑屏障模型功能的影响 被引量:5
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作者 李鸿茹 涂洵崴 +2 位作者 陈正伟 陈愉生 韩莉莉 《中国肿瘤生物治疗杂志》 CAS CSCD 北大核心 2020年第5期528-533,共6页
目的:通过建立体外血脑屏障(blood brain barrier,BBB)模型,探讨人肺腺癌PC-9细胞在CXCR4/SDF-1轴作用下对BBB紧密连接蛋白的影响。方法:利用永生化的小鼠脑微血管内皮细胞Bends进行单层培养,建立体外BBB模型;通过跨内皮细胞电阻(transe... 目的:通过建立体外血脑屏障(blood brain barrier,BBB)模型,探讨人肺腺癌PC-9细胞在CXCR4/SDF-1轴作用下对BBB紧密连接蛋白的影响。方法:利用永生化的小鼠脑微血管内皮细胞Bends进行单层培养,建立体外BBB模型;通过跨内皮细胞电阻(transendothelial electrical resistance,TEER)测定及荧光素钠通透性实验判定体外BBB模型的功能状态以及观察PC-9细胞对体外BBB模型功能的影响。Western blotting检测PC-9细胞在CXCR4抑制剂AMD3100、SDF-1单独或联合(1μg/ml AMD3100,100 ng/ml SDF-1,AMD3100+SDF-1)作用下对BBB模型功能和内皮细胞紧密连接蛋白表达的影响,Transwell迁移实验检测CXCR4/SDF-1轴对PC-9细胞跨BBB模型细胞层迁移能力的影响。结果:Bends细胞单层培养可形成紧密连接的"屏障"并产生较高的TEER,第96 h达到(182.13±5.19)Ω·cm^2;同时行荧光色钠通透性实验结果显示,BBB具有良好屏障性能,其通透率低于空白对照组(P<0.05)。PC-9细胞作用后,BBB模型TEER逐渐降低,第24 h降至(46.7±4.35)Ω·cm^2;同时BBB通透率较作用前显著提高(P<0.05)。PC-9细胞在AMD3100作用下能够上调内皮细胞紧密连接蛋白的表达(P<0.05);AMD3100处理组的PC-9细胞穿过BBB的细胞数较空白组明显减少[(43±2)vs(81±2)个,P<0.05]。结论:AMD3100能够减弱PC-9细胞对Bends细胞建立的体外BBB模型紧密连接的破坏能力。 展开更多
关键词 肺腺癌 PC-9细胞 血脑屏障 bends细胞 紧密连接 跨内皮细胞电阻 迁移 CXCR4/SDF-1轴
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Bending properties and fracture mechanism of C/C composites with high density preform 被引量:9
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作者 张明瑜 苏哲安 +1 位作者 李建立 黄启忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1795-1800,共6页
C/C composites with banded structure pyrocarbon were fabricated by fast chemical vapor infiltration(CVI),with C3H6 as carbon source,N2 as carrier gas,and three-dimensional(3D) 12K PAN-based carbon fabric with high... C/C composites with banded structure pyrocarbon were fabricated by fast chemical vapor infiltration(CVI),with C3H6 as carbon source,N2 as carrier gas,and three-dimensional(3D) 12K PAN-based carbon fabric with high density of 0.94 g/cm3 as preform.Experimental results indicated that the fracture characteristics of C/C composites were closely related to the frequency of high-temperature treatment(HTT) at the break of CVI process.According to the load?displacement curves,C/C composites showed a pseudoplastic fracture after twice of HTT.After three times of HTT,load?displacement curves tended to be stable with a decreasing bending strength at 177.5 MPa.Delamination failure and intrastratal fiber fracture were observed at the cross-section of C/C composites by scanning electronic microscope.Because the content of pyrocarbon and fibers has a different distribution in layers,the C/C composites show different fracture characteristics at various regions,which leads to good toughness and bending strength. 展开更多
关键词 C/C composites chemical vapor infiltration(CVI) high density preform bending properties fracture mechanism
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Unified Solution Method of Rectangular Plate Elastic Bending 被引量:9
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作者 许琪楼 姬同庚 +2 位作者 姜锐 唐国明 姬鸿恩 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期241-248,共8页
The bending of rectangular plate is divided into the generalized statically determinate bending and the generalized statically indeterminate bending based on the analysis of the completeness of calculating condition a... The bending of rectangular plate is divided into the generalized statically determinate bending and the generalized statically indeterminate bending based on the analysis of the completeness of calculating condition at the corner point. The former can be solved directly by the equilibrium differential equation and the boundary conditions of four edges of the plate. The latter can be solved by using the superposition principle. Making use of the recommended method, the bending of the plate with all kinds of... 展开更多
关键词 bending of elastic thin plate rectangular plate unified solution method
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