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基于BONeS设计系统的多媒体互联网通讯仿真 被引量:1
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作者 郭东辉 李立峰 +2 位作者 刘瑞堂 吴伯僖 Gerard Parr 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第4期453-457,共5页
BONeS是美国 Cadence公司 Alta Group开发出的一套用于网络通讯仿真和计算机结构分析的系统设计自动化工具.介绍利用该工具进行多媒体互联网通讯仿真设计,并根据TCP/IP的确认重发和滑动窗口流量控制机制... BONeS是美国 Cadence公司 Alta Group开发出的一套用于网络通讯仿真和计算机结构分析的系统设计自动化工具.介绍利用该工具进行多媒体互联网通讯仿真设计,并根据TCP/IP的确认重发和滑动窗口流量控制机制,分析TCP/IP协议的不同重发延迟和窗口设置方案对多媒通讯QoS的影响. 展开更多
关键词 多媒体通讯 互联网 TCP/IP bones 仿真 INTERNET
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Fast garment simulation with aid of hybrid bones
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作者 吴博 陈寅 +2 位作者 徐凯 程志全 熊岳山 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2218-2226,共9页
A data-driven method was proposed to realistically animate garments on human poses in reduced space. Firstly, a gradient based method was extended to generate motion sequences and garments were simulated on the sequen... A data-driven method was proposed to realistically animate garments on human poses in reduced space. Firstly, a gradient based method was extended to generate motion sequences and garments were simulated on the sequences as our training data. Based on the examples, the proposed method can fast output realistic garments on new poses. Our framework can be mainly divided into offline phase and online phase. During the offline phase, based on linear blend skinning(LBS), rigid bones and flex bones were estimated for human bodies and garments, respectively. Then, rigid bone weight maps on garment vertices were learned from examples. In the online phase, new human poses were treated as input to estimate rigid bone transformations. Then, both rigid bones and flex bones were used to drive garments to fit the new poses. Finally, a novel formulation was also proposed to efficiently deal with garment-body penetration. Experiments manifest that our method is fast and accurate. The intersection artifacts are fast removed and final garment results are quite realistic. 展开更多
关键词 DATA-DRIVEN linear blend skinning hybrid bones INTERACTIVE
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Study on Production of Rubber Sealing Strips with Steel Bones
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作者 WANG Xiao-ping, LI Zhu-guo, YAO Zhen-qiang, XU Zheng-song (School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期8-,共1页
Rubber sealing strips with steel bones are used in car manufacturing that produced in large quantities. Cutting processes, such as milling and punching, are needed when the strips are produced. Accuracy, smoothness an... Rubber sealing strips with steel bones are used in car manufacturing that produced in large quantities. Cutting processes, such as milling and punching, are needed when the strips are produced. Accuracy, smoothness and flatness of the machined surface have to be guaranteed in the cutting process; moreover, deformation of the steel bone and peeling-off of the rubber must be avoided. Therefore cutting action of rubber/steel strips differs from that of rubber or metal workpiece separately. In this paper, milling and punching of rubber/steel strips were studied with the aim to increase the part quality of a production line for sealing strips of cars. Suitable cutting tools and fixtures are both necessary for cutting of the strips. The teeth of the milling saw should be made knife-edged and the cutting edge of the punching tool be inclined. Fixtures should be used to sustain the workpiece and resist deformation. By using of suitable tools and fixtures, high quality of rubber/steel sealing strips is achieved in the production line. 展开更多
关键词 rubber sealing strip steel bone cutting tool FIXTURE
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A Novel Injectable KGM/Fiber Composite Bone Cement for Bone Defect
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作者 LIU Hanwu ZHAO Qiang +1 位作者 XIAO Ting YAN Tingting 《材料导报》 北大核心 2025年第19期254-261,共8页
The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The b... The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The bone cement primarily consists of tricalcium phosphate(β-TCP),konjac glucomannan(KGM),and hydroxyapatite whisker(HAw).An orthogonal experiment was designed to generate multiple sets of new composite calcium phosphate cement(NCPC)samples,and their setting times were measured.The in vitro compatibility of the new bone cement was assessed through relative cell proliferation rate(RGR)and in vitro cell growth experiments.Mechanical strength and porosity tests were conducted for each group of bone cement,and cross-sectional morphology was observed.The results demonstrate that the bone cement exhibits favorable properties such as self-curing,mechanical robustness,and resistance to collapse.The optimum formulation involves a doping ratio of 5/15(wt%)HAw and HA,an additional amount of 1.2wt%KGM,and a liquid citric acid concentration of 2wt%.Porosity tests confirmed that the material has high compressive strength and a favorable porosity of 27%,creating conducive conditions for cell growth,proliferation,and material degradation.Moreover,in vitro cell culture experiments revealed excellent biocompatibility of the material.Consequently,the developed NCPC emerges as a potential candidate material for applications of bone implantation. 展开更多
关键词 bone cement calcium phosphate orthogonal test setting time konjac glucomannan
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Electronic structure and ultraviolet spectra of p-C_(6)H_(4)-C_(20)
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作者 CHEN Xin 《原子与分子物理学报》 CAS 北大核心 2025年第3期21-28,共8页
Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localize... Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same level.Based on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)H_(4)-C_(20) were calculated.Calculation results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)H_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring plane.Two absorption peaks of p-C_(6)H_(4)-C_(20) locate at about 319 nm and 236 nm,respectively. 展开更多
关键词 p-C_(6)H_(4)-C_(20) Bone orders UV spectrum Electron-hole analyses π-electron delocalization analyses
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Comprehensive research on Late Eocene Hulgana cf.H.ertnia(Rodentia:Ischyromyidae)
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作者 LI Lan-Xin LI Qian 《古脊椎动物学报(中英文)》 北大核心 2025年第3期189-209,共21页
A relatively well-preserved rodent fossil,including its incisors,cheek teeth,and postcranial skeleton,was collected from the Baiyin Obo in Siziwang Banner,Nei Mongol.A multifaceted research approach was undertaken in ... A relatively well-preserved rodent fossil,including its incisors,cheek teeth,and postcranial skeleton,was collected from the Baiyin Obo in Siziwang Banner,Nei Mongol.A multifaceted research approach was undertaken in this study to conduct a comprehensive analysis on the newly discovered specimen.Based on a morphological comparison,the new specimen was identified as Hulgana cf.H.ertnia within the Ischyromyidae family.Incisive enamel microstructure analysis revealed the typical pauciserial enamel structure of Hulgana.Bone histological analysis indicates that the specimen represents a juvenile individual,which is consistent with the ontogenetic stage indicated by dental developmental stage and wear pattern.The application of geometric morphometrics to the calcaneus and bone histology of the femur and phalanx further substantiates the taxonomic classification of Hulgana as a terrestrial and cursorial rodent,exhibiting a degree of fossorial ability.This classification is analogous to that of certain extant cricetids and ground squirrels. 展开更多
关键词 Baiyin Obo Nei Mongol Late Eocene Hulgana geometric morphometrics locomotion enamel microstructure bone histology
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Artificial intelligence models based on non-contrast chest CT for measuring bone mineral density 被引量:1
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作者 DUAN Wei YANG Guoqing +6 位作者 LI Yang SHI Feng YANG Lian XIONG Xin CHEN Bei LI Yong FU Quanshui 《中国医学影像技术》 CSCD 北大核心 2024年第8期1231-1235,共5页
Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quan... Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quantitative CT(QCT)BMD examination were retrospectively enrolled and divided into training set(n=304)and test set(n=76)at a ratio of 8∶2.The mean BMD of L1—L3 vertebrae were measured based on QCT.Spongy bones of T5—T10 vertebrae were segmented as ROI,radiomics(Rad)features were extracted,and machine learning(ML),Rad and deep learning(DL)models were constructed for classification of osteoporosis(OP)and evaluating BMD,respectively.Receiver operating characteristic curves were drawn,and area under the curves(AUC)were calculated to evaluate the efficacy of each model for classification of OP.Bland-Altman analysis and Pearson correlation analysis were performed to explore the consistency and correlation of each model with QCT for measuring BMD.Results Among ML and Rad models,ML Bagging-OP and Rad Bagging-OP had the best performances for classification of OP.In test set,AUC of ML Bagging-OP,Rad Bagging-OP and DL OP for classification of OP was 0.943,0.944 and 0.947,respectively,with no significant difference(all P>0.05).BMD obtained with all the above models had good consistency with those measured with QCT(most of the differences were within the range of Ax-G±1.96 s),which were highly positively correlated(r=0.910—0.974,all P<0.001).Conclusion AI models based on non-contrast chest CT had high efficacy for classification of OP,and good consistency of BMD measurements were found between AI models and QCT. 展开更多
关键词 OSTEOPOROSIS bone density tomography X-ray computed artificial intelligence
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Investigation of bioactivity and biodegradability of Mg-bioceramic implants:An in vitro study for biomedical applications
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作者 ESMAIELZADEH Omar EIVANI Ali Reza +3 位作者 MEHDIZADE Maryam TAJALI Nooshin S.H.MOUSAVI ANIJDAN JAFARIAN Hamid Reza 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期2992-3013,共22页
In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessme... In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessment of bioactivity,biodegradation rate,and corrosion behavior of the resultant composites were investigated in simulated body fluid(SBF).The results showed that during the immersion of composites in SBF for 28 d,due to the release of Ca^(2+)and PO_(4)^(3-)ions,hydroxyapatite(HA)crystals with cauliflower shaped morphology were deposited on the surface of composites,confirming good bioactivity of composites.In addition,due to the uniform distribution of bioceramic powders throughout Mg matrix,grain refinement of the Mg matrix,and uniform redistribution of secondary phase particles,the polarization resistance increased,and the biodegradation rate of composites significantly reduced compared to monolithic Mg matrix.The polarization corrosion resistance of Mg-ZnO increased from 0.216 to 2.499 kΩ/cm^(2)compared to monolithic Mg alloy.Additionally,Mg-ZnO composite with the weight loss of 0.0217 g after 28 d immersion showed lower weight loss compared to other samples with increasing immersion time.Moreover,Mg-ZnO composite with the biodegradation rate of 37.71 mm/a exhibited lower biodegradation rate compared to other samples with increasing immersion time. 展开更多
关键词 Mg-bioceramic bone implants friction stir processing bioactivity in vitro biodegradation BIOCORROSION
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三种常用的仿真软件 被引量:2
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作者 张砾 吕柏 梁振兴 《电讯技术》 北大核心 2000年第2期34-39,共6页
介绍了目前常用三种仿真软件 :OPNET、BONeS和COMNETIII的主要功能和核心技术 ,并对它们的一些主要技特点进行了比较。
关键词 通信网络 仿真软件 OPENET COMNET bones
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BMP-2基因转染对兔骨髓间充质干细胞碱性磷酸酶活性和钙含量的影响 被引量:10
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作者 张雁儒 张辉 +1 位作者 马辉 王义生 《郑州大学学报(医学版)》 CAS 北大核心 2014年第1期102-105,共4页
目的:观察骨形成蛋白2(BMP-2)基因转染对骨髓间充质干细胞(BMSCs)碱性磷酸酶(ALP)活性和钙含量的影响。方法:成年大耳白兔16只,经髂后上嵴抽取骨髓组织混合后培养、分离BMSCs。取第3代细胞,采用电转法转染pcDNA3.1-BMP-2质粒。在扩大培... 目的:观察骨形成蛋白2(BMP-2)基因转染对骨髓间充质干细胞(BMSCs)碱性磷酸酶(ALP)活性和钙含量的影响。方法:成年大耳白兔16只,经髂后上嵴抽取骨髓组织混合后培养、分离BMSCs。取第3代细胞,采用电转法转染pcDNA3.1-BMP-2质粒。在扩大培养的第7、14、21、28和35天时收集细胞,用相应试剂盒对细胞ALP活性和钙含量进行测定,在扩大培养的第21天采用RT-PCR检测细胞BMP-2 mRNA的表达水平。以未转染细胞作对照。结果:转染组细胞BMP-2 mRNA相对表达水平为(1.652±0.082),对照组为(0.473±0.021),转染组BMSCs中BMP-2 mRNA的表达明显提高(t=2.192,P=0.005)。转染组细胞内ALP活性和钙含量较对照明显提高(P<0.01)。结论:转染BMP-2基因的BMSCs表现出明显的成骨活性,可以应用为骨组织工程研究的种子细胞。 展开更多
关键词 骨形成蛋白2 骨髓间充质干细胞 碱性磷酸酶 BONE morphogenetic protein 2
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雷公藤多苷对强直性脊柱炎患者成纤维细胞中BMP-2表达的影响 被引量:4
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作者 张洪长 张莹 +3 位作者 刘明昕 唐燕 张鹏飞 潘志 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2014年第6期1187-1191,共5页
目的:探讨雷公藤多苷(LGTDG)对骨形态发生蛋白(BMP)信号转导通路及BMP-2表达的影响,阐明LGTDG抗强直性脊柱炎(AS)骨化的作用机制。方法:体外培养的AS成纤维细胞分为对照组与0.5、1.0、1.5和2.0 mg·L-1给药组,检测各组细胞内碱性磷... 目的:探讨雷公藤多苷(LGTDG)对骨形态发生蛋白(BMP)信号转导通路及BMP-2表达的影响,阐明LGTDG抗强直性脊柱炎(AS)骨化的作用机制。方法:体外培养的AS成纤维细胞分为对照组与0.5、1.0、1.5和2.0 mg·L-1给药组,检测各组细胞内碱性磷酸酶(ALP)活性及最佳药物浓度;CCK-8法检测1.0mg·L-1给药组的细胞增殖率;生化检测法定量检测对照组与1.0 mg·L-1给药组BMP-2表达水平;Western blotting法检测对照组与1.0mg·L-1给药组BMP-2和Cbfal蛋白表达。结果:各给药组细胞中ALP活性均低于对照组,其中以1.0mg·L-1给药组细胞的ALP活性为最低(P<0.01)。CCK-8法检测,1.0mg·L-1给药组AS成纤维细胞增殖率明显低于对照组(P<0.01),LDTDG诱导第4天细胞增殖率最高,进入平台期后细胞的增殖率开始下降。生化检测法和Western blotting法检测,1.0mg·L-1给药组BMP-2的蛋白表达明显低于对照组(P<0.01)。结论:LGTDG通过对BMP信号转导通路的影响有效地抑制AS成纤维细胞内BMP-2表达,延缓细胞向成骨型分化导致AS骨化发生。 展开更多
关键词 雷公藤多苷 强直性脊柱炎 骨形态发生蛋白 2 成纤维细胞 BONE morphogenetic protein-2
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Dog Bone栅型MOS场效应晶体管的等效宽长比计算 被引量:2
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作者 孟丽娅 刘泽东 +2 位作者 胡大江 岳陈平 喻依虎 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第6期98-102,共5页
Dog Bone栅型MOS场效应晶体管是一种对称性的、防辐射总剂量效应的版图结构。为了计算其等效宽长比,把它划分为常规结构的主MOS晶体管和非常规结构的边缘MOS晶体管2种类型的并联。借助Silvaco TCAD工艺与器件仿真工具构建了它的模型,分... Dog Bone栅型MOS场效应晶体管是一种对称性的、防辐射总剂量效应的版图结构。为了计算其等效宽长比,把它划分为常规结构的主MOS晶体管和非常规结构的边缘MOS晶体管2种类型的并联。借助Silvaco TCAD工艺与器件仿真工具构建了它的模型,分析了主MOS晶体管的宽度、长度和边缘MOS晶体管的多晶硅与有源区的交叠宽度对边缘MOS等效宽长比的影响,得到拟合的Dog Bone栅型MOS晶体管等效宽长比的计算公式。采用CSMC 0.5μm DPTMCMOS混合信号工艺制作了样管,对实验测量值和公式计算值进行比较,Dog Bone栅型MOS场效应晶体管的等效宽长比的计算公式与实验能够较好地吻合。 展开更多
关键词 DOG BONE MOS 防辐射加固 器件仿真
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8×8Banyan结构的ATM视频/数据混合系统性能分析
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作者 匡泓 贾世楼 +2 位作者 邹昕光 林尚平 王晗阳 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2001年第1期73-75,共3页
在电子与通信系统设计过程中 ,利用仿真方法的灵活性和成本低的特点 ,分析所设计系统的性能参数是否符合设计指标 ,能够大大降低采用新技术和新方法的风险 ,并有助于降低工程成本 .对目前最好的网络协议仿真工具BONeS的作了介绍 ,并用BO... 在电子与通信系统设计过程中 ,利用仿真方法的灵活性和成本低的特点 ,分析所设计系统的性能参数是否符合设计指标 ,能够大大降低采用新技术和新方法的风险 ,并有助于降低工程成本 .对目前最好的网络协议仿真工具BONeS的作了介绍 ,并用BONeS系统仿真工具对一个以 8× 8Banyan结构为核心的视频数据混合传输ATM系统进行物理建模和仿真分析 ,揭示了该系统在一定业务负载下能提供的服务质量 .得到了交换机缓存长度和信元丢失率 ,交换延迟的关系 ,对工程设计有一定的指导意义 . 展开更多
关键词 仿真 bones ATM BANYAN结构 视频/数据混合系统 性能
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Ad-BMP-2/GFP转染兔骨髓间充质干细胞前后生物学特性的研究 被引量:3
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作者 宁寅宽 李强 +3 位作者 蔡伟良 武成聪 陈佳滨 石正松 《中国骨质疏松杂志》 CAS CSCD 北大核心 2014年第12期1387-1392,共6页
目的对Ad-BMP-2/GFP转染兔骨髓间充质干细胞(BMSCs)前后的生物学特性进行观察。方法采用密度梯度离心结合贴壁培养法分离获取第10代兔BMSCs,应用流式细胞仪检测细胞表面抗原CD44、CD45、CD29的表达,用携带BMP2和GFP基因的腺病毒转染细... 目的对Ad-BMP-2/GFP转染兔骨髓间充质干细胞(BMSCs)前后的生物学特性进行观察。方法采用密度梯度离心结合贴壁培养法分离获取第10代兔BMSCs,应用流式细胞仪检测细胞表面抗原CD44、CD45、CD29的表达,用携带BMP2和GFP基因的腺病毒转染细胞。分别通过倒置荧光显微镜下观察转染前后细胞形态改变,MTT法分析转染前后细胞增殖的情况,体外Ⅰ型胶原免疫组化染色和钙结节茜素红染色以观察转染前后细胞的成骨分化情况,Western Blot检测转染前后细胞内目的蛋白表达。结果密度梯度离心结合贴壁培养法能获取高纯度第10代兔BMSCs,流式细胞仪检测显示CD44、CD29阳性,CD45阴性。Ad-BMP-2/GFP转染兔BMSCs后在荧光显微镜下观察到绿色荧光,细胞形态向成骨方向分化,在短时间内能促进兔BMSCs的增殖(P<0.05),Ⅰ型胶原免疫组化染色、茜素红染色均呈阳性,Western Blot显示细胞内稳定表达BMP-2目的蛋白。结论 Ad-BMP-2/GFP能成功转染兔骨髓间充质干细胞并能改变其生物学特性。 展开更多
关键词 骨髓间充质干细胞 骨形态发生蛋白2 腺病毒载体 生物学特性 基因治疗 BONE morphogenetic PROTEIN 2
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异种去抗原松质骨成骨效能的实验研究 被引量:2
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作者 张晔 刘湘宁 +1 位作者 李婷薇 赖仁发 《中国病理生理杂志》 CAS CSCD 北大核心 2014年第8期1467-1471,共5页
目的:研究异种去抗原松质骨与基因重组人骨形成蛋白2(recombinant human bone morphogenetic protein 2,rhBMP-2)复合后的生物相容性和成骨效能。方法:28只新西兰大白兔28处颌骨缺损完全随机分为3组:异种去抗原松质骨/rhBMP-2组(A组)、... 目的:研究异种去抗原松质骨与基因重组人骨形成蛋白2(recombinant human bone morphogenetic protein 2,rhBMP-2)复合后的生物相容性和成骨效能。方法:28只新西兰大白兔28处颌骨缺损完全随机分为3组:异种去抗原松质骨/rhBMP-2组(A组)、异种去抗原松质骨组(B组)和空白对照组(C组)。A组和B组每组12处骨缺损,于4、8和12周分别进行大体观察、X线检查、HE染色和新生骨量测定;C组共4处骨缺损于12周时进行大体观察、X线检查和HE染色。结果:X线显示,随着时间的增长,2组的植入骨逐渐降解吸收,由自体骨替代,A组较B组显著;C组12周时无法完成愈合。骨密度测量显示,随着时间的增长,A和B组的骨密度值增加,2组之间存在显著差异(P<0.05)。HE染色可见A组的新生血管、纤维组织和新生骨均较B组多;植入骨降解速度快于B组;A组新生骨面积大于B组(P<0.05)。结论:异种去抗原松质骨是rhBMP-2的良好载体;异种去抗原松质骨/rhBMP-2复合材料能持续成骨,可加速骨缺损修复的速度,是一种较好的骨修复材料。 展开更多
关键词 骨形成蛋白2 异种去抗原松质骨 骨缺损 BONE morphogenetic protein2
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Amelioration of collagen-induced arthritis by CD95 (Apo-1/Fas)-ligand gene transfer 被引量:2
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作者 Jennifer L.Horton Elena B.Samoilova +2 位作者 Thomas A.Judge Laurence A.Turka James M.Wilson 《中国实验血液学杂志》 CAS CSCD 1997年第3期322-322,共1页
Both rheumatoid arthritis and animal models ofautoimmune arthritis are characterized by hyper-activation of synovial cells and hyperplasia of the synovialmembrane. The activated synovial cells produceinflammatory cyto... Both rheumatoid arthritis and animal models ofautoimmune arthritis are characterized by hyper-activation of synovial cells and hyperplasia of the synovialmembrane. The activated synovial cells produceinflammatory cytokines and degradative enzymes whichlead to destruction of cartilage and bones. Effectivetreatment of arthritis may require elimination of most orall activated synovial cells. The death factor 展开更多
关键词 collagen CARTILAGE DESTRUCTION cytokines bones elimination enzymes AUTOIMMUNE inflammation unlike
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全身骨显像评价前列腺癌骨转移特点及其临床应用价值 被引量:5
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作者 崔炳强 《中国临床医学影像杂志》 CAS 北大核心 2010年第11期817-818,共2页
目的:通过99mTc-MDP全身骨显像与MRI、CT及前列腺特异性抗原(PSA)的比较,评价前列腺癌骨转移的特点及其临床应用价值。方法:对60例经病理证实为前列腺癌的患者肘静脉注射99mTc-MDP 925MBq,约3小时后行全身骨显像。在行全身骨显像的前后... 目的:通过99mTc-MDP全身骨显像与MRI、CT及前列腺特异性抗原(PSA)的比较,评价前列腺癌骨转移的特点及其临床应用价值。方法:对60例经病理证实为前列腺癌的患者肘静脉注射99mTc-MDP 925MBq,约3小时后行全身骨显像。在行全身骨显像的前后1周内进行MRI、CT、PSA测定。结果:全身骨显像与MRI在诊断前列腺癌骨转移的阳性率方面无明显差异,且有较高的阳性一致率,均高于CT检查;全身骨显像显示,前列腺癌骨转移的好发部位为骨盆、脊柱;前列腺癌骨转移患者的血清PSA值明显高于无骨转移者。结论:全身骨显像是早期发现前列腺癌骨转移的首选方法,有极高的临床实用价值。 展开更多
关键词 全身骨显像 前列腺癌骨转移 转移特点 临床应用价值 PROSTATE carcinoma OSSEOUS metastasis bone imaging whole body 前列腺特异性抗原 临床实用价值 PSA MRI 早期发现 阳性率 静脉注射 患者 好发部位 方法 病理证实 转移者
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丝素蛋白/羟基磷灰石多孔复合材料修复骨缺损研究
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作者 施咏毅 罗敏清 +2 位作者 毛丽 卢神州 Yong-yi Min-qing Shen-zhou 《丝绸》 CAS 北大核心 2010年第10期1-4,11,共5页
为了探讨丝素蛋白/羟基磷灰石(SF/HA)复合多孔支架材料的制备及其用于骨缺损的修复,采用超声波凝胶干燥法制备了SF/HA复合材料;以脱胶茧丝为增强材料,水溶性淀粉为制孔剂,通过去离子水萃取法除去淀粉,制备了SF/HA多孔复合材料。对其孔... 为了探讨丝素蛋白/羟基磷灰石(SF/HA)复合多孔支架材料的制备及其用于骨缺损的修复,采用超声波凝胶干燥法制备了SF/HA复合材料;以脱胶茧丝为增强材料,水溶性淀粉为制孔剂,通过去离子水萃取法除去淀粉,制备了SF/HA多孔复合材料。对其孔隙率及抗压强度进行测试,并将其植入兔股骨缺损处观察修复的情况。SF/HA多孔复合材料的孔隙率接近75%,孔径尺寸分布约从几微米到400μm,并且孔隙之间相互贯通,其抗压强度可达10 MPa以上,植入兔股骨缺损处未见引起骨组织明显的炎症反应及骨坏死,术后12周发现基本修复骨缺损部位,而空白对照组没有骨生成。SF/HA多孔复合材料可以满足骨组织工程支架的基本要求,用于骨缺损的修复。 展开更多
关键词 丝素蛋白 羟基磷灰石 多孔复合材料 修复骨缺损 Treatment BONE Defect Composites 兔股骨缺损 抗压强度 复合多孔支架材料 骨组织工程支架 法制备 孔隙率 水溶性淀粉 植入 增强材料 炎症反应 去离子水 凝胶干燥 基本要求
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DEFECTIVE LYMPHOCYTES SUPPORTING HEMATOPOIESIS IN PATIENTS WITH PAROXYSMAL NOCTURNAL HEMOGLOBINURIA
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作者 高清平 《中国实验血液学杂志》 CAS CSCD 1995年第4期399-405,共7页
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemo-lytic disease in which there is a stem cell disorder of clonal nature. Previous studies have demonstrated that the numbers of burst-forming units-erythroid... Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemo-lytic disease in which there is a stem cell disorder of clonal nature. Previous studies have demonstrated that the numbers of burst-forming units-erythroid (BFU-E) and colony-forming units-granulocyte / macrophage (CFU-GM) from bone marrow of PNH patients growing in the medium containing PHA-LCM from the normai donors were more reduced than those of normai bone marrow. The purpose of present study was to investigate if PNH lymphocytes are defective in supporting hematopoiesis in vitro. PHA-LCM from PNH blood was added to the culture medium for the growth of PNH and normai BFU-E and CFU-GM. The numbers of PNH bone marrow BFU-E and CFU-GM in the medium containing PHA-LCM from PNH blood were less than those from normai blood; the numbers of normai bone marrow BFU-E and CFU-GM grown in the medium containing PHA-LCM from PNH blood were more decreased than those from normai blood. The results suggest that diminished numbers of PNH bone marrovv BFU- 展开更多
关键词 PHA-LCM hematopoietic PROGENITOR bone MARROW PAROXYSMAL NOCTURNAL HEMOGLOBINURIA
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联合表达BMP2和Sox9促进体外培养间充质干细胞成软骨分化 被引量:8
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作者 廖军义 周年 +7 位作者 林良波 易世雄 凡廷旭 赵辰 胡宁 梁熙 司维柯 黄伟 《南方医科大学学报》 CAS CSCD 北大核心 2014年第3期317-322,共6页
目的探讨联合表达骨形态发生蛋白2(BMP2)和Sox9对间充质干细胞(MSCs)成软骨分化的影响,为构建组织工程软骨提供实验依据。方法以小鼠胚胎骨髓MSCs(C3H10T1/2)为种子细胞,重组腺病毒BMP2诱导其分化,联用重组腺病毒Sox9过表达Sox9信号,重... 目的探讨联合表达骨形态发生蛋白2(BMP2)和Sox9对间充质干细胞(MSCs)成软骨分化的影响,为构建组织工程软骨提供实验依据。方法以小鼠胚胎骨髓MSCs(C3H10T1/2)为种子细胞,重组腺病毒BMP2诱导其分化,联用重组腺病毒Sox9过表达Sox9信号,重组腺病毒GFP作为对照。Real-Time PCR检测成软骨标志物Ⅱ型胶原(Col2a1)、蛋白聚糖(Aggrecan)、X型胶原(Col10a1)表达变化;Alcian blue染色了解细胞基质糖胺聚糖合成情况;免疫组化和Western blotting检测Col2a1合成情况。结果 BMP2能诱导C3H10T1/2细胞成软骨分化,当与Sox9联合作用时,Sox9可促进BMP2诱导的(Col2a1、Aggrecan、Col10a1)基因表达上调;促进细胞基质糖胺聚糖、Col2a1蛋白合成。结论 BMP2与Sox9联合作用可以促进体外培养MSCs成软骨分化,可能为组织工程软骨提供新的方法。 展开更多
关键词 骨形态发生蛋白2 SOX9 间充质干细胞 成软骨分化 BONE morphogenetic protein 2 SOX9
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