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World Journal of Gastroenterology 2008年第38期14卷 5810-5815页

作者： Wei Huang xiang-long tian Yun-Lin Wu Jie Zhong Li-Fen Yu Sheng-Ping Hu Biao Li Department of Nuclear Medicine Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai 200025 China Department of Gastroenterology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai 200025 China

AIM: To study the inhibitory effect of baculovirus- mediated normal epithelial cell specific-1 (NES1) gene therapy on gastric cancer (GC) in vitro and in vivo. METHODS: We first constructed recombinant baculovirus vectors and then transfected them into gastric cancer cells (SGC-7901). Efficiency of the baculovirus for gene transfer into SGC-7901 cells and cell growth curves were detected by fluorescence microscopy, Western blot and 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in vitro, respectively. The therapeutic effect of this gene therapy on GC was confirmed in xenografted nude mice. Tumor growth was determined by tumor volume, and expression of NES1 in tumor was analyzed by immunohistochemistry. RESULTS: Baculovirus vectors were successfully transfected into SGC-7901 cells. SGC-7901 cells transfected with the NES1 gene inhibited cell growth. In the Bac-NES1 treated group, tumor growth was significantly reduced with a high level of NES1 expression CONCLUSION: Baculovirus-mediated NES1 gene can be used in gene therapy for GC.

关键词： Gastric cancer Normal epithelial cellspecific-1 gene Baculovirus Gene therapy

现代测绘技术自动化技术在地形测量中的应用分析

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世界有色金属 2018年第3期43卷 22-22,24页

作者：项田龙孙璧辉云南黄金矿业集团股份有限公司云南昆明650200

测绘技术作为一项发展历史十分悠久的技术工作,在新时代的发展中有着十分重要的意义,是现代社会有序发展的重点工作。自动化就是现在测绘工作中一项重点技术,但是自动化技术在地形测量中的应用工作在当下工作难度较大,对相关问题的整治... 详细信息

测绘技术作为一项发展历史十分悠久的技术工作,在新时代的发展中有着十分重要的意义,是现代社会有序发展的重点工作。自动化就是现在测绘工作中一项重点技术,但是自动化技术在地形测量中的应用工作在当下工作难度较大,对相关问题的整治及管理工作也是经常出现问题,对自动化技术在地形测量中的应用工作的探讨是重点,文章就以此为方向展开分析。

关键词：现代测绘技术自动化技术地形测量应用难题发展前景

Test Verification and Design of the Bicycle Frame Parameters

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 716-725页

作者： ZHANG long xiang Zhongxia LUO Huan tian Guan Key Laboratory of Mechanism Theory and Equipment Design of Education Tianjin University

Research on design of bicycles is concentrated on mechanism and auto appearance design, however few on matches between the bike and the rider. Since unreasonable human-bike relationship leads to both riders＇ worn-out joints and muscle injuries, the design of bicycles should focus on the matching. In order to find the best position of human-bike system, simulation experiments on riding comfort under different riding postures are done with the lifemode software employed to facilitate the cycling process as well as to obtain the best position and the size function of it. With BP neural network and GA, analyzing simulation data, conducting regression analysis of parameters on different heights and bike frames, the equation of best position of human-bike system is gained at last. In addition, after selecting testers, customized bikes based on testers＇ height dimensions are produced according to the size function. By analyzing and comparing the experimental data that are collected from testers when riding common bicycles and customized bicycles, it is concluded that customized bicycles are four times even six times as comfortable as common ones. The equation of best position of human-bike system is applied to improve bikes＇ function, and the new direction on future design of bicycle frame parameters is presented.

关键词： bike modeling data mining fatigue dynamics simulation oxygen uptake

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富血小板血浆促进创面愈合的细胞和分子机制

中国组织工程研究 2025年第13期29卷 2793-2801页

作者：龙晨艳程飚田举广东医科大学第一临床医学院广东省湛江市524000 广东医科大学中山市人民医院烧伤整形美容科广东省中山市528400 南部战区总医院烧伤整形科广东省广州市510030

背景:尽管富血小板血浆在促进创面愈合方面显示出治疗潜力,但其临床应用仍需要进一步的研究和验证。此外,对于富血小板血浆作用的机制仍存在一些争议和不确定性。目的:通过对富血小板血浆促进创面愈合的机制进行概述和分析,以增进对该... 详细信息

背景:尽管富血小板血浆在促进创面愈合方面显示出治疗潜力,但其临床应用仍需要进一步的研究和验证。此外,对于富血小板血浆作用的机制仍存在一些争议和不确定性。目的:通过对富血小板血浆促进创面愈合的机制进行概述和分析,以增进对该治疗方法的理解,为未来的基础研究和临床应用提供有益的指导。方法:在中国知网、PubMed数据库检索2000年1月至2023年12月发表的相关文献。英文检索词为“platelet rich plasma,PRP,wound,wound healing,refractory wounds,chronic wounds,cellular and molecular mechanisms,signaling pathways,regenerative medicine”,中文检索词为“富血小板血浆,PRP,创面,伤口,创面愈合,难愈性创面,慢性创面,细胞和分子机制,信号通路,再生医学”。根据纳入和排除标准,最终对80篇文献进行综述。结果与结论:①富血小板血浆在创面愈合中具有许多潜在的优势,它能够提供丰富的生长因子和细胞因子等生物活性物质;②富血小板血浆可以调节参与创面愈合的各种细胞类型的功能,包括表皮细胞、血管内皮细胞、成纤维细胞、干细胞和炎症细胞等;③在富血小板血浆疗法中,细胞外囊泡、线粒体对于创面愈合可能扮演着重要角色;④负载富血小板血浆水凝胶可广泛用于增强组织再生和作为药物传递的功能性载体;⑤富血小板血浆对创面细胞外基质合成和降解起调节作用,从而影响伤口愈合过程中基质重建;⑥富血小板血浆可能通过动态调节多种信号通路和上皮间质转化来影响组织修复与再生,从而为创面愈合的研究提供了全新的视角。

关键词：富血小板血浆生长因子创面愈合细胞和分子机制信号通路再生医学

X-ray flares raising upon magnetar plateau as an implication of a surrounding disk of newborn magnetized neutron star

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Research in Astronomy and Astrophysics 2021年第12期21卷 326-336页

作者： tian-Ci Zheng long Li Le Zou xiang-Gao Wang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China

The X-ray flares have usually been ascribed to long-lasting activities of the central engine of gamma-ray bursts(GRBs),e.g.,fallback *** GRB X-ray plateaus,however,favor a millisecond magnetar central *** fallback accretion can be significantly suppressed due to the propeller effect of a ***,if the propeller regime cannot resist the mass flow onto the surface of the magnetar efficiently,the X-ray flares raising upon the magnetar plateau would be *** this work,such peculiar cases are connected to the accretion process of the magnetars,and an implication for magnetar-disc structure is *** investigate the repeated accretion process with multi-flare GRB 050730,and give a discussion for the accretion-induced variation of the magnetic field in GRB 111209 *** or more flares exhibit in the GRB 050730,060607 A and 140304 A;by adopting magnetar mass M=1.4 M_(⊙)and radius R=12 km,the average mass flow rates of the corresponding surrounding disk are 3.53×10^(-4)M_(⊙)s^(-1).4.23×10^(-4)M_(⊙)s^(-1),and 4.33×10^(-4)M_(⊙)s^(-1),and the corresponding average sizes of the magnetosphere are 5.01×10^(6)cm,6.45 x 10^(-6)cm,and 1.09×10^(-7)cm,respectively.A statistic analysis that contains eight GRBs within 12 flares shows that the total mass loading in single flare is~2×10^(-5)M_(⊙).In the lost mass of a disk,there are about 0.1%used to feed a collimated jet.

关键词： accretion accretion disk stars:magnetars gamma-ray burst:individual(GRB 050730,GRB 111209A)

Novel approach for active vibration control of a flexible missile

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Defence Technology（防务技术） 2020年第4期16卷 956-967页

作者： Cheng-long Pan Ji-li Rong tian-fu Xu Da-lin xiang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Norinco Group Aviation Ammunition Research Institute Harbin 150030China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

This paper investigates the feasibility of using an active dynamic vibration absorber(ADVA) for active vibration control of a flexible missile system through *** on the principles of a dynamic vibration absorber(DVA),a ring-type ADVA is first designed to attenuate the elastic vibration of the flexible missile,and the design of the active controller adopts the proportional-integral-derivative(PID)control *** motion equations of a flexible missile with an ADVA,which is subjected to follower thrust at its aft end,are derived using the Lagrangian *** the minimum of the root mean square(RMS) of the lateral displacement response of the center of mass as the objective function,a genetic algorithm(GA) is used to optimize the parameter of the DVA and PID *** numerical calculations show that the ADVA and DVA are effective in suppressing the vibration and provide approximately 41.2% and 17.6% improvement,respectively,compa red with the case of no DVA,The ADVA has better performance than the DVA,When the missile is subjected to follower thrust,the effect of vibration reduction is more effective than the case without follower *** is feasible to reduce vibration and improve the stability of flexible missiles by means of the ADVA.

关键词： Flexible missile PID controller Active dynamic vibration absorber Genetic algorithms

Physical and numerical investigation on fluid flow and inclusion removal behavior in a single-strand tundish

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Journal of Iron and Steel Research International 2023年第6期30卷 1182-1198页

作者： Qi Quan Zhi-xiao Zhang tian-peng Qu xiang-long Li Jun tian De-yong Wang School of Iron and Steel Soochow UniversitySuzhou 215137JiangsuChina

Aiming at the problem that the existence of inclusions in the tundish continuous casting process can easily lead to quality defects of the slab,the stainless steel continuous casting tundish was taken as the research *** effects of flow control device,inclusion density and inclusion size on the mixing characteristics of molten steel and inclusion behavior in tundish were *** results showed that compared with the tundish without flow control device,the average residence time of molten steel was prolonged by about 49 s,the dead zone volume fraction was reduced by 8.93%,and the piston fluid integral rate was increased by 12.68%.In the turbulence inhibitor(TI)tundish with weir-dam combination,the removal rate of inclusions with a density of 2700 kg m^(-3) and a particle size of 5 lm is 63.32%,while the removal rate of large inclusions with a density of 150μm could reach 89.04%.When the inclusion particle size was 10-50μm and the density was 2700-4500 kg m^(-3),the effect of inclusion density on inclusion removal rate was *** the same time,when weir-dam combination TI tundish was set,the inclusions were mainly limited to the slag-metal interface of the first and second chambers of the *** removal rate of inclusions in the first chamber was generally improved,with 10μm inclusions accounting for 47.67% and 150μm inclusions accounting for 60.69%.Furthermore,it has the best effect on the removal of small-size inclusions,especially those less than 70μm.

关键词： Non-metallic inclusion Flow control device Residence time distribution curve Removal behavior Discrete particle model

Mechanical properties and microstructure of Mg-treated and Catreated industrial H13 steel after quenching and tempering

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Journal of Iron and Steel Research International 2024年第8期31卷 1987-2001页

作者： Jun-ying Yue Dong Hou De-yong Wang tian-peng Qu xiang-long Li Jun tian School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The effect of magnesium treatment and calcium treatment on the microstructure and mechanical properties of industrial H13 steel after quenching and tempering was *** impact toughness and tensile tests were mainly carried out,and the microstructure was observed by scanning electron microscopy,electron backscattered diffraction,and X-ray *** results show that magnesium treatment is still feasible in industrial *** is mainly manifested in the refinement of lath martensite and *** with calcium treatment,the prior austenite grains and carbides size of industrial H13 steel treated with magnesium decreased by 3.17μm after *** quenching and tempering,the carbides(especially V-rich carbides)in Mg treatment obviously spheroidized and distributed uniformly and increased in quantity *** lath martensite size is reduced from 2.45 to 2.31μ*** suggests that magnesium treatment was able to yield smaller grains and more evenly distributed ***,the impact toughness,yield strength,and ultimate tensile strength of industrial H13 steel with magnesium treatment increased by 28%,65.5 MPa and 123.7 MPa,*** increment of strength mainly comes from dislocation strengthening,grain refinement strengthening,and precipitation strengthening,among which precipitation strengthening accounts for the largest proportion.

关键词： Industrial H13 steel Mg treatment Heat treatment Carbide-Mechanical property

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng Liu Xin Ma Shaojie tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

Magnetic Resonance Urography and X-ray Urography Findings of Congenital Megaureter

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Chinese Medical Sciences Journal 2011年第2期26卷 103-108页

作者： tian-ran Li xiang-ke Du tian-long Huo Department of Radiology Peking University People＇s Hospital Beijing 100044 China

Objective To observe the imaging findings of congenital megaureter in order to enhance the understanding of this disease. Methods Image data of 5 patients with congenital megaureter and 2 misdiagnosed patients were analyzed, and image findings of congenital megaureter were summarized. Elscint Prestig 2.0T superconductive magnetic resonance urography （MRLI） with conventional sequence （spin-echo, T 1W1560 ms/16 ms; fast spin-echo, T2WI 9600 ms/96 ms） was performed. Raw data were acquired with fast spin-echo sequence from heavy T2-weighted image （9600 ms/120 ms）. Post-processing method of MRH was the maximum in- tensity projection with three-dimensional reconstruction in the workstation. Intravenous pyelography （IVP） was conducted, in which X-ray films were taken 7 minutes, 15 minutes, and 30 minutes after injecting contrast agent, except that in 2 patients the films were taken delayed at 60 and 90 minutes. X-ray retrograde pyelography was performed on 2 patients, successful in one but failed in the other. Results The dilated ureter showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in conventional MRI. The mass wall was intact, uniform in thickness, and showing hy- pointensity on Tl-weighted and T2-weighted images. The MRH images showed a retroperitoneal mass appearing as an elongated tubular cystic structure spreading from kidney to bladder. MRLI also revealed dilated calices and renal pelvis, pelviureteric obstruction, and renal duplication. The main signs of congenital megaureter in X-urography was significant dilatation of ureter, or normal renal pelvis with ureter dilatation, hydronephrosis, deformity, and displacement. Conclusions MRH with X-urography could visualize the characteristics of congenital megaureter, including the dilation of renal pelvis and ureter, calculi, urinary tract duplication, and stenosis location. The two techniques can complement each other in disease diagnosis and provide more detailed information for

关键词： congenital megaureter magnetic resonance urography intravenous pyelo-graphy