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Physical Simulation for Large-Bore Copper Vapor Laser

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Chinese Physics Letters 2000年第1期17卷 19-21页

作者： yu de-li WANG Run-Wen TAO Yong-Xiang Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800

On the basis of the electric circuit differential equations and the nonlinear partial differential equations of kinetics,a kinetic model for a series of large-bore copper-vapor lasers is carried *** the consistent computational results the radial kinetic parameters such as the stimulating electric Geld and the plasma electron temperature are *** factors,which evidently influence the output power and the beam quality of the large-bore copper-vapor laser,are the buffer gas pressure and the charging voltage.

关键词： kinetic copper Simulation

The study on the mechanical characteristics of articular cartilage in simulated microgravity

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Acta Mechanica Sinica 2012年第5期28卷 1488-1493页

作者： Hai-Jun Niu Qing Wang yue-Xiang Wang Ang li lian-Wen Sun Yan Yan Fan Fan de-yu li yu-Bo Fan Key Laboratory of the Ministry of Education for Biomechanics and Mechanobiology State Key Laboratory of Software Development EnvironmentSchool of Biological Science and Medical EngineeringBeihang University School of Biomedical Engineering Southern Medical University department of Ultrasound People Liberation Army General Hospital

The microgravity environment of a long-term space flight may induce acute changes in an astronaut＇s musculo-skeletal systems. This study explores the effects of simulated microgravity on the mechanical characteristics of articular cartilage. Six rats underwent tail suspension for 14 days and six additional rats were kept under normal earth gravity as controls. Swelling strains were measured using high-frequency ultrasound in all cartilage samples subject to osmotic loading. Site-specific swelling strain data were used in a triphasic theoretical model of cartilage swelling to determine the uniaxial modulus of the cartilage solid matrix. No severe surface irregularities were found in the cartilage samples obtained from the control or tail-suspended groups. For the tail-suspended group, the thickness of the cartilage at a specified site, as determined by ultrasound echo, showed a minor decrease. The uniaxial modulus of articular cartilage at the specified site decreased significantly, from （6.31 ± 3.37） MPa to （5.05 ± 2.98）MPa （p 〈 0.05）. The histology- stained image of a cartilage sample also showed a reduced number of chondrocytes and decreased degree of matrix staining. These results demonstrated that the 14 d simulated microgravity induced significant effects on the mechanical characteristics of articular cartilage. This study is the first attempt to explore the effects of simulated microgravity on the mechanical characteristics of articular cartilage using an osmotic loading method and a triphasic model. The conclusions may provide reference information for manned space flights and a better understanding of the effects of microgravity on the skeletal system.

关键词： Simulated microgravity Articular cartilage.Triphasic theory High-frequency ultrasound Uniaxialmodulus

Vasculogenic mimicry:a pivotal mechanism contributing to drug resistance in antiangiogenic therapy

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Oncology and Translational Medicine 2024年第3期10卷 119-125页

作者： Shu-Min Dang Dan Yang Zhi-Yi Wang Xiang-Ming Ding Xiu-ling li de-yu li Dong-Xiao li department of Gastroenterology People’s Hospital of Zhengzhou UniversityHenan Provincial People’s HospitalZhengzhouHenanChina Henan Key Medical Laboratory for Molecular Immunology of Digestive Diseases Henan Provincial People’s HospitalZhengzhouHenanChina department of Hepatobiliary Surgery People’s Hospital of Zhengzhou UniversityHenan Provincial People’s HospitalZhengzhouHenanChina Henan Provincial Key Medical Laboratory for Hepatobiliary and Pancreatic Diseases Henan Provincial People’s HospitalZhengzhouHenanChina

The growth of solid tumors relies on establishing a robust blood supply,with angiogenesis playing a key role in this intricate *** on this understanding,therapeutic strategies targeting tumor angiogenesis have been ***,the clinical effectiveness of antiangiogenic therapy(AAT)in treating tumors has not lived up to *** recent years,vasculogenic mimicry(VM)has attracted increasing attention from the academic community as a longstanding but often overlooked mechanism of nonangiogenic tumor *** the tumor microenvironment,neoplastic cells can autonomously form vessel-like structures,creating a blood supply that does not rely on endothelial *** phenomenon,known as VM,is a critical marker of aggressive tumors and may play a significant role in conferring resistance to *** this review,we thoroughly examine the evidence,clinical characteristics,and mechanisms of VM across various tumor types and explore its potential role and importance in resistance to AAT and the development of new antitumor therapies.

关键词： Vasculogenic mimicry Antiangiogenic therapy Angiogenesis Tumor microenvironment Immunotherapy

Muricatenol, a linear Acetogenin from Annona muricata (Annonaceae)

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Chinese Chemical Letters 2000年第3期11卷 239-242页

作者： de yu li Jing Guang yu Xiu Zhen LUO Lan SUN Shi lin YANG (Institute of Medicinal Plant development. Chinese Academy of Medical Sciences and Peking Union Medical College. Beijing 100094) Chinese Acad Med Sci Inst Med Plant Dev Beijing 100094 Peoples R China Peking Union Med Coll Beijing 100094 Peoples R China

Muricatenol 1, a new acetogenin, has been isolated from the seeds of Annona muricata L.. Compound 1 is a C-37 acetogenin without any THF rings. with four hydroxyls and one double bond in the long aliphatic chain. The hydroxyls of 1 are located at C-4, C-10, C-18 and C-19. respectively. The vicinal diet at C-18/C-19 is threo-configuration, and the double bond at C-14/C-15 is cis-configuration.

关键词： Annona muricata Annonaceae acetogenins muricatenol

X-ray focusing using an x-ray lens composed of multi-square polycapillary slices

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Chinese Physics B 2022年第2期31卷 278-284页

作者： Kai Pan Tian-Cheng Yi Zhao Wang Mo Zhou yu-de li Zhi-Guo liu Xiao-Yan lin Tian-Xi Sun College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China Beijing Key Laboratory of Applied Optics Beijing 100875China Key Laboratory of Beam Technology Ministry of EducationBeijing 100875China Spallation Neutron Source Science Center Dongguan 523803China Institute of Applied Electronics China Academy of Engineering PhysicsMianyang 621900China

A new type of x-ray lens composed of multi-square polycapillary slices(ASPXRL)used in focusing parallel x-ray beam was presented in this *** with conventional x-ray polycapillary lens,ASPXRL can provide smaller and brighter *** effects of the manufacturing imperfections on focusing quality of ASPXRL were evaluated with the values of transmission efficiency and *** is suggested that ASPXRL has application prospects as a condenser lens for x-ray microscopy and flux collectors for x-ray analytical instruments.

关键词： x-ray optics polycapillary x-ray lens with square channels

Load Rate of Facet Joints at the Adjacent Segment Increased After Fusion

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Chinese Medical Journal 2015年第8期128卷 1042-1046页

作者： Hui li Bao-Qing Pei Jin-Cai Yang Yong Hai de-yu li Shu-Qin Wu department of Biomedical Engineering Key Laboratory for Biomeehanics and Mechanobiology of Ministry of Education School of Biological Science and Medical Engineering Beihang University Beijing 100191 China department of Orthopedics Beijing Chao-Yang Hospital Beijing 100020 China

Background： The cause of the adjacent segment degeneration （ASD） after fusion remains unknown. It is reported that adjacent facet joint stresses increase alter anterior cervical discectomy and fusion. This increase of stress rate may lead to tissue injury. Thus far, the load rate of the adjacent segment facet joint after fusion remains unclear. Methods： Six C2-C7 cadaveric spine specimens were loaded under tour motion modes： Flexion, extension, rotation, and lateral bending, with a pure moment using a 6° robot arm combined with an optical motion analysis system. The Tecscan pressure test system was used for testing facet joint pressure. Results： The contact mode of the facet joints and distributions of the force center during different motions were recorded. The adjacent segment facet joint forces increased faster after fusion, compared with intact conditions. While the magnitude of pressures increased, there was no difference in distribution modes before and after fusion. No pressures were detected during flexion. The average growth velocity during extension was the fastest and was significantly faster than lateral bending. Conclusions： One of the reasons for cartilage injury was the increasing stress rate of loading. This implies that ASD after fusion may be related to habitual movement before and after fusion. More and faster extension is disadvantageous for the facet joints and should be reduced as much as possible.

关键词： Action Related Adjacent Segment degeneration Facet Joints Load Fusion Load Rate

Synthesis, Characterization and Antitumor Activities of Co, Ni, Cu, Zn Complexes with 1,4,7,10-tetrakis(4-nitrobenzyl)-1,4,7,10 tetraazacyclododecane Macrocyclic ligand

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Chinese Journal of Structural Chemistry 2000年第1期19卷 39-47页

作者： KONG de\|yuan a* \ XIE yu\|li a\ XIE yu\|yuan a\ HUANG Xiao\|Ying ba (Shanghai Institute of Materia Medica, the Chinese Academy of Sciences, Taiyuan Road 294, Shanghai, 200031, P. R. China) b (department of Chemistry, Rugters University, New Jer 中科院上海药物所上海 2 0 0 0 31 Rugters University 美国 New Jersey 08102

New tetraazamacrocyclic ligand with 1,4,7,10 tetrakis(4 nitrobenzyl) pendent groups (C 36 H 40 N 8O 8, M r =712.76) crystallized in the monoclinic system, P2 1/n space group with unit cell parameters: a=7.834(2), b=22.902(6), c=10\^147(3), β=106.53(2)°, V=1745(1) 3, Z=2, D c =1.356 g/cm 3, λ (Mo Kα )=0.71069; μ =0.92cm -1 , F(000)=752, T =296K. The final R and R w values are 0\^065 and 0.066, respectively. The Cu(Ⅱ), Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ) complexes with this new ligand have been synthesized and characterized by elemental analyses, IR, UV, ESI MS and molar conductance. The macrocyclic ligand molecular structure is centrosymmetrical. All complexes are in accordance with the general formula: M(L)(NO 3) 2·nH 2O (M=Co, Ni, Cu, n=2; M=Zn, n=4; L=C 36 H 40 \|N 8O 8). The central metal ions coordinate to four nitrogen atoms of azamacrocycle and two oxygen atoms of one nitrate ion. Preliminary pharmacological tests against P 388 and A 549 tumor cell lines showed that all these complexes had considerable activities in vitro.

关键词： synthesis macrocyclic ligand antitumor activity crystal structure

Utility of adenovirus-mediated Fas ligand and bcl-2 gene transfer to modulate rat liver allograft survival

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Hepatobiliary & Pancreatic Diseases International 2006年第4期5卷 505-510页

作者： de-Sheng Wang, yu li, Ke-Feng Dou, Kai-Zong li and Zhen-Shun Song department of Hepatobiliary Surgery, Xijing Hospital Research Centre of Cell Engineering , Fourth Military Medical University, Xi’an 710032, China department of Hepatobiliary Surgery Xijing Hospital Fourth Military Medical University Xi'an 710032 China. wangdesh@***

BACKGROUND: Expression of Fas ligand (FasL) on the graft by gene transduction is expected to introduce apoptosis to lymphocytes to protect rejection, but the FasL-expressing graft cells may also induce apoptosis as the graft usually expresses Fas antigens. In this study, a strong antiapoptotic gene, bcl-2, was cotransfected with the FasL gene in rat liver graft to protect against Fas- mediated cell death and to prolong recipient survival. METHODS: Orthotopic liver transplantation was done in a strain combination of DA to LEW rats. After donor vascular isolation, adenovirus-mediated FasL and bcl-2 genes were cotransfected in the liver graft. RESULTS: Intragraft expression of FasL mRNA was constitutively expressed after adenovirus-mediated transduction, although expression of FasL increased mildly in control grafts. Bcl-2 mRNA was highly expressed at 2 days after reperfusion. In contrast, lower expression of bcl-2 was observed in the control group. The average survival of the gene transferred allografts increased from (9.8+1.3) days to (18.5+8.7) days compared with the control group. CONCLUSION: Our results indicate that rat liver allografts can be protected against host immune responses by adenovirus-mediated FasL and bcl-2 transfection, and that bcl-2 expression prevents the graft from Fas-mediated apoptosis.

关键词： Fas ligand bcl-2 liver transplantation immune tolerance

利用基因芯片对赖型钩体毒力基因差异表达与致病相关性的探讨

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四川大学学报（医学版） 2015年第1期46卷 11-15页

作者：余德立鲍朗四川大学华西基础医学与法医学院感染免疫研究室成都610041

目的通过对连续动物传代和试管培养的赖型钩端螺旋体部分致病基因表达差异性的检测,分析赖型钩端螺旋体特异性基因表达与毒力改变之间的联系,了解赖型钩端螺旋体致病过程和发病机制。方法将27只豚鼠分为3组(n=9),分别经腹部皮下接种1mL... 详细信息

目的通过对连续动物传代和试管培养的赖型钩端螺旋体部分致病基因表达差异性的检测,分析赖型钩端螺旋体特异性基因表达与毒力改变之间的联系,了解赖型钩端螺旋体致病过程和发病机制。方法将27只豚鼠分为3组(n=9),分别经腹部皮下接种1mL体内培养钩体(体内培养组)、体外培养钩体(体外培养组)或钩体培养基(培养基组),接种钩体浓度为108/mL并处于对数生长期。在接种后15d内观察其发病和死亡状况,测量其体温体质量变化情况,并于接种后第15d将存活豚鼠处死,测量脏器系数,了解经不同环境培养的钩体的毒力情况;以赖型钩端螺旋体标准株DNA为模板,采用PCR技术扩增出所选特定基因作为探针,使用点样仪进行芯片点样。分别提取经豚鼠体内连续数代培养的钩端螺旋体RNA与EMJH培养基中培养的钩端螺旋体RNA,逆转录后分别使用Cy5和Cy3进行荧光标记,并与基因芯片进行杂交。扫描后通过分析两种荧光强度的比值,了解赖型钩端螺旋体相关毒力基因的差异表达情况。结果接种后,体内培养组豚鼠存活率为0%,体外培养组豚鼠存活率为88.9%,培养基组豚鼠全部存活;体内培养组豚鼠较其余两组豚鼠体温升高(P<0.05)、体质量下降(P<0.05);体内培养组豚鼠心、肺、肾的脏器系数较体外培养组及培养基组豚鼠更大(P<0.05);解剖后,体内培养组豚鼠肺部出血情况较其余两组更为严重;通过基因芯片,检测到溶血素基因以及其他与钩体生存致病能力相关的基因呈现出不同程度的改变,溶血素基因LA1027、LA1029、LA4004、LA3050、LA3540、LA0327、LA0378、LA1650、LA3937、O抗原连接酶基因LA2089、鞭毛动力蛋白基因LA3576、外膜蛋白基因LA0011及Loa22基因上调。结论赖型钩体经连续体内培养后毒力增高,钩体毒力变化与其基因表达差异存在联系,了解这些基因的变化意义对阐明钩体的致病机制有重要意义。

关键词：钩端螺旋体基因芯片差异表达毒力基因溶血素