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组织工程软骨生物支架材料研究新进展

中国组织工程研究与临床康复 2007年第18期11卷 3625-3628页

作者：林智军王万明解放军南京军区福州总医院骨二科福建省福州市350025

目的:软骨组织损伤后自身修复能力有限,组织工程学使得关节软骨的生物学替代物即人工软骨显示出美好的前景。软骨生物支架材料为组织工程的重要一环,探讨软骨生物支架材料的研究进展对构建人工软骨具有重大意义。资料来源:应用计算机检... 详细信息

目的:软骨组织损伤后自身修复能力有限,组织工程学使得关节软骨的生物学替代物即人工软骨显示出美好的前景。软骨生物支架材料为组织工程的重要一环,探讨软骨生物支架材料的研究进展对构建人工软骨具有重大意义。资料来源:应用计算机检索PubMed数据库2003-01/2006-12有关组织工程软骨生物支架材料的文章,检索词“articular,tissue engineering,scaffold”,限定文章语言种类为English。同时计算机检索中文期刊全文数据库2003-01/2006-12期间的相关文章,检索词“软骨、组织工程,支架”,限定文章语言种类为中文。资料选择:对资料进行初审,选取符合研究要求的有关文章找全文。纳入标准:文章所述的内容应与组织工程软骨生物支架材料研究相关。排除标准:重复或类似的同一研究、Meta分析、综述文献。资料提炼:共收集到185篇相关文章,排除重复或类似的同一研究、综述,30篇符合研究要求。资料综合:人工软骨生物支架材料按其来源可分为:天然生物材料、人工合成高分子材料和复合材料。①天然生物材料生物相容性、细胞黏附性好,亲水性强,但力学强度差、吸收过快,而且难以大批量生产。②人工合成高分子材料具有可控降解速度、力学强度好、易于塑形,但亲水性不够,对细胞的黏附性较弱以及有免疫反应、排斥反应等。③复合材料即将两种或两种以上具有互补特征的生物相容性可降解材料,按一定比例和方式组合,可设计出结构与性能优化的三维材料,以弥补单用人工合成或天然生物材料的缺陷,提高支架的整体性能。复合材料的制备不仅包括同一类生物材料的复合,还包括不同类别生物材料之间的交叉复合。结论:通过对支架材料进行表面修饰、采用新型构建技术以及利用天然和合成材料的各自优势联合应用,进行多材料复合,以研制出具有生物相容性好、力学适应能力强的复合材料、仿生材料、智能材料将是近年来人工软骨生物支架材料的主要研究方向。

关键词：组织工程支架软骨生物材料

Two New Glycosides from Rubus amabilis

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Chinese Chemical Letters 2000年第10期11卷 897-900页

作者： Chen, XC Jia, zj Lanzhou Univ Natl Lab Appl Organ Chem Dept Chem Lanzhou 730000 Peoples R China

A pregnane glycoside and a lignan glycoside were isolated from the aerial parts of Rubus amabilis. Their structures were elucidated as 3-O-beta-D-glucopyranosyl-3 beta.15 alpha-dihydroxypregn-5-en-20-one and (-)-secoi... 详细信息

关键词： Rubus amabilis Rosaceae pregnane lignan glycoside

A New Benzofuranosesquiterpene Dimer from Ligularia Virgaurea

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Chinese Chemical Letters 1997年第4期8卷 315-316页

作者： Wang, BG Jia, zj LANZHOU UNIV DEPT CHEMNATL LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

A new benzofuranosesquiterpene dimer, named virgaurin B, has been isolated from the roots of Ligularia virgaurea and its structure has been elucidated by spectroscopic evidence.

关键词： Chen A New Benzofuranosesquiterpene Dimer from Ligularia Virgaurea

NEOLIGNAN GLUCOSIDES FROM PEDICULARIS TORTA

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Chinese Chemical Letters 1996年第2期7卷 145-148页

作者： Wang, CZ Jia, zj LANZHOU UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA LANZHOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Two new neolignan glucosides, tortosides D and E were isolated from plants of Pedicularis torta. On the basis of spectral evidence, tortosides D and E were determined as (7R.8S)-dehydrodiconiferyl-9-O-beta-D-4 ''-O-methyl-glucopyranoside and (7R,8S)-5-methoxy-dihydrodehydrodiconiferyl alcohol-9'-O-beta-D-glucopyranoside, respectively.

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NEOLIGNAN GLUCOSIDES FROM PEDICULARIS LONGIFLORA

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Chinese Chemical Letters 1996年第2期7卷 141-144页

作者： Wang, CZ Jia, zj LANZHOU UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA LANZHOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Two new neolignan glucosides, longiflorosides A and B were isolated from whole plants of Pedicularis lungiflora. On the basis of spectral evidence, longiflorosides A and B were determined as (7R, 8S)-4-O-methyl-dehydrodiconiferyl alcohol-9'-O-beta-D-glucopyranoside and (erythro)-1-(4-O-beta-D-glucopyranosyl-3,5-dimethoxy-phenyl)-2-:2-methoxy-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol, respectively.

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ANALYSIS ON SMALL SCALE BRIDGING IN FIBROUS MONOLITHIC CERAMICS

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Acta Mechanica Solida Sinica 1999年第3期12卷 227-238页

作者： Wu, zj Cai, QH Tsing Hua Univ Dept Mech Engn Beijing 100084 Peoples R China

Based on shear lag model of interface between fiber and matrix, a new formula that relates the crack opening displacement and bridging force in fibrous monolithic ceramics was constructed under the framework of small scale bridging. This formula was applied to predict the fracture resistance or R-curve response of a three-point bending specimen made of fibrous monolithic ceramics. A parametric investigation on the influences of fiber volume fraction, fiber radius, characteristics of constituents, BN's fracture toughness and specimen's geometry on the bridging forces and fracture resistance in Si3N4/BN composite was carried out. The upper and lower limits of the R-curve of Si3N4/BN in small scale bridging were derived. This research revealed the role played by the above parameters in the fracture toughness of fibrous monolithic ceramics.

关键词： fibrous monolithic ceramics fiber bridging R-curve fracture toughness

The rotation and the phase transition in solid C60

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Chinese Journal of Chemistry 1996年第6期14卷 481-489页

作者： Xu, zj Yan, JM CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

The interaction between C-60's in solid C-60 has been calculated by (exp-6-1) potential, and the cause and the controlled factor of the high rapid rotations of C-60's were discussed. In order to describe the disordered degree of C-60 rotation, an equivalent M is introduced. The phase transitions at the similar to 260 K and at the similar to 90 K are studied from the viewpoint of C-60 rotation. The potential barriers of the ordered rotation below the similar to 260 K and the disordered rotation above the similar to 260 K have been given, and the effect of the external pressure on the temperature of phase transition has also been given.

关键词： fullerene C-60 molecular rotation phase transition

Phase Structure Change of Mo-Si System duringMechanical Alloying

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Journal of Materials Science & Technology 1999年第5期15卷 423-426页

作者： Liu, SJ Qu, XH Liu, zj Huang, BY Cent S Univ Technol State Key Powder Met Changsha 410083 Peoples R China

The structure of Mo-15.16 Si, Mo-30 Si and Mo-36.3 Si (wt pct) elemental powder mixture during mechanical alloying was studied using electron microscopy and X-ray diffraction. It had been found that, in all the systems under study, silicon disappeared initially during mechanical alloying (MA). In the Mo-Si systems all products were in form of amorphous state after long time milling, but there were different intermediate products. MoSi2 and Mo5Si3 intermetallic compounds in the Mo-30Si and Mo-36.3Si (wt pct) were directly synthesized from elements through inter-diffussion process. The high density of defects and interface of nano-crystal lines induced by ball milling would promote the reaction process. Only in the Mo-15.16Si (wt pct) system was Mo(Si) supersaturated solid solution formed as an intermediate product. Schematic free-energy diagram of Mo-Si system based on the thermodynamics was used to analyze the difference among the intermediate state products.

关键词： Molybdenum alloys

ON THE CONVERGENCE OF THE BRENT METHOD

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Journal of Computational Mathematics 1994年第1期12卷 1-20页

作者： WANG, DR HUANG, zj SHANGHAI UNIV SCI & TECHNOL DEPT MATHSHANGHAIPEOPLES R CHINA FUDAN UNIV DEPT STAT & OPERAT RESSHANGHAIPEOPLES R CHINA

In this paper, we establish the semi-local convergence theorem of the rent method with regional estimation. By an in-depth investigation in to the algorithm structure of the method, we convert the Brent method into an approximate Newton method with a special error term. Bsaed on such equivalent variation, under a similar condition of the Newton-Kantorovich theorem of the Newton method, we establish a semi-local convergence theorem of the Brent method. This theorem provides a sufficient theoretical basis for initial choices of the Brent method.

关键词： holds Choice vergence convergent elimination otherwise Brent Dennis Cornell approximate