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The Potential Mechanisms Underlying Aspirin-induced Inhibition of Ovarian Tumor Cell Growth

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生物医学工程学杂志 2005年第S1期22卷 145-147页

作者： Yu LIU~1 Jin KE~2 Shi-Quan LIU~1 Fu-Xiang ZHOU~1 Cong-Hua XIE~1 Yun-Feng ZHOU~(1△)1(Department of Radio-Chematherapy of Zhongnan Hospital and Cancer research center, wuhan University, wuhan 430071, china)2(Key Lab. for Oral Biomedical Engineering of Ministry of Education, School & Hospital of Stomatology, wuhan University, wuhan 430079, china) Department of Radio- Chematherapy of Zhongnan Hospital and Cancer research center Wuhan University Wuhan 430071 China Key Lab. for Oral Biomedical Engineering of Ministry of Education School & Hospital of Stomatology Wuhan University Wuhan 430079 China

1 IntroductionOvarian cancer remains the most lethal disease of the gynecological cancers. Owing to the lack of an effective screening approach combined with inadequate therapeutic approach for advanced disease, fewer than 25% of ovarian cancers are identified at an early curable stage. Thus these make ovarian cancer a strong candidate for chemoprevention. In 2001, Akhmedkhanov et al. demonstrated a 2-3 folds decrease in epithelial ovarian cancer associated with Aspirin use. These epidemiological observations suggest that an improved understanding of the mechanisms by which NSAID may decrease the development of ovarian cancer could lead to improved approaches for chemoprevention of this deadly disease. In this research, we explored the potential mechanism underlying epidemiological observations that ovarian cancer occurs at a lower frequency in women exposed to Aspirin(ASP).

关键词： In Cell The Potential Mechanisms Underlying Aspirin-induced Inhibition of Ovarian Tumor Cell Growth COX

Circular Interpolation Algorithms of 5-Axis Simultaneous CNC System

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武汉理工大学学报 2006年第S2期28卷 407-411页

作者： ZHENG Kuijing~(1.2) SHANG BO~2 1.Mechanical Engineering College,Yanshan University,Qinhuangdao 066004,china 2.research and development center,GSK CNC Equipment Co.,Ltd.,Guangzhou 510165,china Mechanical Engineering College Yanshan UniversityQinhuangdao 066004China research and development center GSK CNC Equipment Co.Ltd.Guangzhou 510165China research and development center GSK CNC Equipment Co.Ltd.Guangzhou 510165China

Spatial circular arc can be machined conveniently by a 5-axis NC machine *** on the data sampling method,circular interpolation in two-dimensional plane is discussed *** key is to solve the problem of circular center ex- pressed in the workpiece coordinate system by means of the transformation *** interpolation in three-dimensional space is analyzed in *** method of undetermined coefficient is used to solve the center of the spatial circle and the method of coor- dinate transformation is used to transform the spatial circle into the *** arc in three-dimensional space can be ma- chined by the positional 5-axis machining and the conical surface can be machined by the continuous 5-axis *** velocity control is presented to avoid the feedrate *** interpolation algorithms are tested by a simulation example and the inter- polation algorithms are proved *** algorithms are applied to the 5-axis CNC system software.

关键词： Index Terms-Circular interpolation 5-axis CNC

Screen for stage-specific expression genes between tail bud stage and heartbeat beginning stage in embryogenesis of gynogenetic silver crucian carp

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Cell research 2002年第2期12卷 133-142页

作者： YAO HUA SHI, JUN LIU, JIAN HONG XIA, JIAN FANG GUIState Key laboratory of Freshwater Ecology and Biotechnology, wuhan center for developmental Biology, Institute of Hydrobiology, Chinese Academy of Sciences, wuhan 430072, china 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 1State Key laboratory of Freshwater Ecology and Biotechnology Wuhan Center for Developmental Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169 TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS d

关键词： SSH embryonic development differential expression genes gynogenesis silver crucian carp.

Effect of Welding Heat Inputs on Microstructure and Mechanical Properties of the Welding Affected Zone of 800MPa Grade Ultra Fine Microstructure Steel

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Effect of Welding Heat Inputs on Microstructure and Mechanic...

Lithosphere types in North china:Evidence from geology and geophysics

第二届先进钢铁结构材料国际会议

作者： LIU Jibin~(1,2), HU Lunji~1, WANG Yutao~2, MIAO Kai~2, LIU ZhenQing~2, TIAN ZhiLing~3 (1. Huazhong University of Science and Technology, wuhan 430074, china 2.Technology center of wuhan iron and Steel (Group) Corporation, wuhan 430080,china 3. Central iron and Steel research Institute, Beijing 100080, china)

The microstructure and mechanical properties of the heat affected zone (HAZ) of 800MPa grade ultra fine microstructure steel was investigated by using simulated thermal cycles which represented different welding heat inputs. The analysis of HAZ microstructure found that the bainite was the main structure characteristic during different cooling time, and even in the fast cooling regime, the bainite sheaves consisted of bainite ferrite plates without carbide precipitation. The prior austenite grain of HAZ was coarsening rapidly at relatively lower cooling rate, and the bainite ferrite plates grew longer and almost developed in the same direction within a prior austenite grain. It was found that the HAZ toughness at -20℃deteriorated when the cooling time t was more than 20 seconds, and the Charpy V-notch (CVN) values was about 10J. The simulated HAZ became softer than the base metal when t was longer than 20 seconds. It was suggested that the welding heat input of this kind of 800MPa ultra fine microstructure steel should be controlled within t 15 seconds.

关键词： Ultra Fine Microstructure Steel Heat Affected Zone Heat Input Microstructure Mechanical Properties Bainite

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, china 2. development and research center, china Geological Survey, Beijing 100037, china 3. china University of Geosciences, Beijing 100083, china 4. china University of Geosciences, wuhan 430074, china 5. Information center of Ministry of Land and Resources, Beijing 100812, china 6. Institute of Geology, State Seismological Bureau, Beijing 100029, china 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. development and research center China Geological Survey 100037 Beijing China 3. china University of Geosciences 100083 Beijing China 4. china University of Geosciences 430074 Wuhan China 5. Information center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

Effect of Nb,Mo and Ti on the Microstructures and Mechanical Properties of 700MPa Weathering Steel

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Effect of Nb,Mo and Ti on the Microstructures and Mechanical...

Immunohistochemical localization of Ca^(2+)/calmodulin-dependent kinase in tobacco

第六届国际低合金高强度钢会议

作者： WANG Bing~1,SONG Yu-lai~2,WEN Xiao-ming~3,WANG Hou-xin~4,LIU Qing-you~1 (1.Institute for Structural Materials of CISRI,Beijing 100081,china 2.research and development center of wuhan iron and Steel(Group)Corp.,wuhan 430080,hubei,china 3.Benxi iron and Steel Group Limited Company Benxi 117000,Liaoning,china 4.CITIC-CBMM Microalloying Technology center,Beijing 100081,china)

Using metallurgical structure observation and measurement of mechanical properties such as micro-hardness, tensile test,cold-bend,the effect of Nb,Mo and Ti on the structure and mechanical properties of 700MPa weathering steel was studied under the same rolling *** results show the formation of M/A is promoted by Mo,while inhibited by ***,M/A island,as a hard phase,is harm to the material toughness and plasticity;high M/A island fraction will result in obvious crack during cold *** effect of Nb on increasing the strength of experiment steel is very *** Nb content of 700MPa steel must be higher than 0.05%to ensure the *** optimal mechanical properties of the experiment steel will be gained by the proper match ratio of Nb,Mo and *** industry trial production of 700MPa high-strength weathering steel for container was also developed.

关键词： weathering steel Nb Mo Ti mechanical properties M/A island

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Chinese Science Bulletin 2001年第3期46卷 230-233页

作者： YANG Wannian, LIANG Shuping & LU Yingtangcenter of developmental Biology, College of Life Science, wuhan University, wuhan 430072, china center of developmental Biology College of Life Science Wuhan University Wuhan China

The existence of Ca2+/calmodulin-dependent kinase (CaM kinase, CaMK) in tobacco is verified immuno-logically and its distribution in different tissues of tobacco is studied. It has been demonstrated that CaMK is mainly distributed in early developing anthers, developing ovules and embryos, lateral root primordium, apical meristem and leaf primordium of buds and mesophyll cells and developing vascular bundles of leaves. There is enormous CaM kinase distributed in leaf epidermis fair cells and guard cells of stomas too. Little kinase is found in mature stem or root cells. The distribution properties of CaM kinase in tobacco are consistent with those of CaM, suggesting that there exists the Ca2+ signal transduction pathway mediated by CaM kinase in tobacco and it plays an important role in the plant growth and development.

关键词： CaM kinase immunohistochemical localization tobacco anthers.

PHASE DIAGRAM OF Nd-Fe-B TERNARY SYSTEM——Ⅱ.Two Vertical Sections with Constant Nd and B Respectively,Passing Through Nd_2Fe_(14) B Point

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Acta Metallurgica Sinica(English Letters) 1989年第11期2卷 333-338页

作者： ZHANG Ning, Central iron and Steel research Institute, Ministry of Metallurgical Industry, Beijing, chinaLUO Yang, San Huan New Material research and development center, Academia Sinica, Beijing, china

According to the experimental data of phase transition taken from DTA, metallography, SEM and microzone composition, two vertical sections of the ternary phase diagram (B=5.88 at.-%, Nd≤45.41 at.-% andNd_2Fe_(14)BNd_(1.1)Fe_4B_4 , B≤44.56 at.-%) have been drawn in detail. It is verified that the crystallization of both Nd_2Fe_(14)B and Nd_(1.1)Fe_4B_4 phase, during cooling from melt, would take peritectic reaction instead of solid-liquid congruent precipita- tion.

关键词： Nd-Fe-B phase diagram vertical section

Microstructures and Toughness in Simulated Coarse Grain Heat-affected Zones of Copper-bearing Steel

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Microstructures and Toughness in Simulated Coarse Grain Heat...