检索结果-南通市图书馆

Betal integrin links laminin-mediated adhesion to microtubule assembly during neuronal polarization

在线全文

cnki会议

学校读者我要写书评

暂无评论

Betal integrin links laminin-mediated adhesion to microtubul...

“细胞活动生命活力”——中国细胞生物学学会全体会员代表大会暨第十二次学术大会

作者： Wen-Liang Lei~1,Shi-Ge Xing~2,Xing-Yu Jiang~2,Zhen-Ge Luo~1 1.Institute of Ncurosciencc and Key State Laboratory of Ncurosciencc,Chinese Academy of Sciences,Shanghai,China 2.national Center for NanoScicncc and Technology of China,Beijing,China

Axon specification is believed to involve asymmetric microtubule stabilization in one of the neurites of unpolarized ***,how this polarized microtubule assembly is achieved during axon development is ***,we show that extracellular matrix(ECM) component laminin promotes neuronal polarization via regulating directional microtubule assembly through beta1 integrin(Itgb1).Active Itgb1 was found to be concentrated in distal axons of cultured hippocampal neurons on the laminin ***-regulating Itgb1 expression abolished axon formation,whereas enhancing Itgb1 signaling promoted axon development. Furthermore,genetic ablation of Itgb1 in dorsal telencephalic progenitors caused deficits in axon development of pyramidal neurons in the cerebral ***,laminin contact promotes directional microtubule assembly,a process required for axon *** asymmetric microtubule assembly also depended on Itgb1. Moreover,stabilizing microtubules partially prevented polarization defects caused by Itgb1 down-regulation. Thus,laminin/Itgb1 signaling plays an instructive role in axon initiation and growth,both in vitro and in vivo, through the regulation of microtubule assembly.

关键词：

在线全文

cnki会议

学校读者我要写书评

暂无评论

时间域谱激电法在寻找石墨矿中的应用效果

物探与化探 1987年第6期 422-427页

作者：王绵龄胡正明国家建材局地质公司安徽地质勘探大队

本文概述了重复的方块脉冲电流的时间域测量得到的宽带信息求取Cole-Cole参数的方法。并介绍了安徽某石墨矿带在没有自电或充电率异常但有值异常的位置上,经钻探见到了石墨矿。解释为极化体埋藏深且电阻率很小之故。认为该法对发现深埋... 详细信息

本文概述了重复的方块脉冲电流的时间域测量得到的宽带信息求取Cole-Cole参数的方法。并介绍了安徽某石墨矿带在没有自电或充电率异常但有值异常的位置上,经钻探见到了石墨矿。解释为极化体埋藏深且电阻率很小之故。认为该法对发现深埋藏的极化体和良导极化体是有效的,可弥补自电和常规时间域激电法的不足。在该区值很大的异常上,均见到了质量较好的石墨矿,而充电率大但时间常数不大的异常均为石墨矿化所引起。

关键词：时间域谱激电法充电率石墨矿极化体应用效果

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

喜剧意识:喜剧性的核心

外国文学研究 2005年第5期27卷 152-160页

作者：苏晖华中师范大学文学院

本文提出喜剧意识是喜剧性的核心这一观点。论文首先对喜剧意识的内涵和载体进行了探讨,认为喜剧意识是喜剧的审美主体反思人类社会及人类自身的丑恶、缺陷和弱点,发现其反常、不协调等可笑之处,从而实现对自我与现实的超越;喜剧意识的... 详细信息

本文提出喜剧意识是喜剧性的核心这一观点。论文首先对喜剧意识的内涵和载体进行了探讨,认为喜剧意识是喜剧的审美主体反思人类社会及人类自身的丑恶、缺陷和弱点,发现其反常、不协调等可笑之处,从而实现对自我与现实的超越;喜剧意识的主要载体是喜剧的创作主体和欣赏主体。接着,本文从构成喜剧性系统的喜剧审美客体、创造主体和欣赏主体三个方面阐述喜剧意识是喜剧性的核心这一观点,认为审美客体是喜剧意识的对象化,审美客体应呈现某种矛盾和不协调状态才能体现作家的喜剧意识;创造主体的智慧是喜剧意识的直接体现,艺术家需要对现实的喜剧现象进行理性的思考,也要能以特殊的喜剧艺术思维和手段揭示假象后面的真实;欣赏主体的笑则是喜剧意识的直觉化显现,他们应以一定的内在尺度和审美距离观照喜剧客体才能发笑。喜剧意识的鲜明与否是判别艺术作品是否具有喜剧性及其审美价值高低的主导性因素。

关键词：喜剧性喜剧意识审美客体创作主体欣赏主体人类社会创造主体审美主体喜剧艺术审美距离

在线全文

学校读者我要写书评

暂无评论

一种量子认证协议的设计

通信技术 2002年第9X期35卷 92-94页

作者：杨宇光祝世雄信息产业部电子30所国防重点实验室成都610041

分析文献[1]中提出的“Catch22”问题的解决方案存在的漏洞,然后提出作者自己的解决方案。

关键词： “Catch22”问题量子认证协议 KDC

在线全文

学校读者我要写书评

暂无评论

银离子注入多晶α－Fe的低周疲劳研究

上海有色金属 1995年第1期16卷 19-22页

作者：王红卫杨大智史维东陈騑巴图大连理工大学三束材料表面改性国家重点实验室中科院金属研究所材料疲劳与断裂国家重点实验室

本文研究了多晶α－Ｆｅ经９０ｋｅＶ，６×１０（１６）ｉｏｎｓ／ｃｍ２银离子注入前后的低周疲劳性能，结果表明，离子注入改善了α－Ｆｅ的低周疲劳性能，疲劳韧性系数和疲劳韧性指数的绝对值分别从未注入时的０．０７６和０．３２... 详细信息

本文研究了多晶α－Ｆｅ经９０ｋｅＶ，６×１０（１６）ｉｏｎｓ／ｃｍ２银离子注入前后的低周疲劳性能，结果表明，离子注入改善了α－Ｆｅ的低周疲劳性能，疲劳韧性系数和疲劳韧性指数的绝对值分别从未注入时的０．０７６和０．３２增加到０．２１６和０．４２。作者认为，注入离子阻碍了体心立方基体螺位错的交滑移是疲劳韧性提高和低周疲劳性能改善的主要机制；另外，注入引起的缺陷强化和固溶强化对提高低周疲劳性能也有一定作用。

关键词：离子注入低周疲劳塑性应变银离子化学热处理

Biochemical and structural studies of Iml3p-Chl4p complex

在线全文

学校读者我要写书评

暂无评论

Biochemical and structural studies of Iml3p-Chl4p complex

第十七届国际生物物理大会;第十二届中国生物物理大会

作者： Yuyong Tao~(1,2),Xu Li~(1,2),Liwen Niu~(1,2),Maikun Teng~(1,2) 1.Hefei national Laboratory for Physical Sciences at the Microscale and School of Life Sciences,University of Science and Technology of China 2.Key Laboratory of Structural Biology,Chinese Academy of Sciences

Yeast Iml3p and Chl4p were identified as two members of budding yeast outer kinetochore and localized to kinetochore in a Ctf19p-dependent *** of Iml3p and Chl4p would cause defects in the segregation of minichromosom... 详细信息

关键词： Biochemical and structural studies of Iml3p-Chl4p complex

Numerical Simulation of Powder Injection Molding Filling Process Based on ANSYS

在线全文

cnki会议

学校读者我要写书评

暂无评论

Numerical Simulation of Powder Injection Molding Filling Pro...

The Fourth International Conference on Physical and Numerical Simulation of Materials Processing (ICPNS’2004)

作者： Zhoushun ZHENG, Xuanhui QU, Yunping LI and Jianfeng GUO national Key Lab for Powder Metallurgy, Central South University, Changsha, 410083,P.R.China Department of Applied Mathematics and Applied software, Central South University, Changsha, 410083, P.R.China School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, P.R.China

A mathematical model of two-dimensional flows of PIM derived from the momentum, continuity equations and the heat transfer equation is obtained. The formula of calculating the flow conductance and the pressure equation are deduced when the no slip boundary condition is employed at the wall, and the pressure equation is a no-linear elliptic partial differential equation. The flow front locations, distribution of velocities, temperature and pressure are simulated by the finite element analysis software ANSYS. Simulation results indicate that it is in the final filled part that defects appear easily. The region in which the defects may occur during the PIM process can be predicted.

关键词： Numerical simulation Powder injection molding Mathematical model ANSYS

在线全文

cnki会议

学校读者我要写书评

暂无评论

用于油气勘探项目战略经济评价的实物期权法

石油学报 2003年第1期24卷 15-18,24页

作者：张永峰杨树锋贾承造陈汉林凌春华浙江大学理学院地球科学系浙江杭州310027 中国石油天然气股份有限公司北京100011 浙江大学管理学院浙江杭州310027

用于项目经济评价的传统的净现值法本身具有一定的局限性 ,油气勘探项目又具有投资额大、周期长、技术工艺复杂、风险大的特点 ,因而净现值法在油气勘探项目的战略经济评价和投资决策中的应用存在很大的缺陷。它忽略了期权的价值 ,因此... 详细信息

用于项目经济评价的传统的净现值法本身具有一定的局限性 ,油气勘探项目又具有投资额大、周期长、技术工艺复杂、风险大的特点 ,因而净现值法在油气勘探项目的战略经济评价和投资决策中的应用存在很大的缺陷。它忽略了期权的价值 ,因此经常低估投资项目的真实价值 ,从而易导致错误的决策。本文将实物期权法引入油气勘探项目的风险投资决策中 ,系统地介绍了实物期权法的原理、特点和应用实例。实物期权法作为一种战略经济评价的新方法 ,它改变了过去人们对不确定性因素的看法 ,不再将不确定性因素作为消权的因素来看待。

关键词：油气勘探经济评价净现值法实物期权法投资决策

在线全文

学校读者我要写书评

暂无评论

上海市区474例儿童碘营养状况调查

卫生研究 1999年第5期28卷 273-274页

作者：柳启沛梁惠芳上海医科大学公共卫生学院营养与食品卫生学教研室

It has been hypothesized that homocysteine(HCY) can induce apoptosis at the organogenesis-stage of chick embryos and which can be the relationship between HCY and congenital defects of neural tube and heart. Exogenous D, L-HCY (4-8 mumol/embryo) was injected into the place near brain and the yolk of the day 4 embryos. Then they were harvested 2 days later and examined by flow cytometry, histopathology, electronic microscope, in situ end labeling of DNA strand break and methylgreen-pyronine double staining. The change of plasma HCY level of day 10 embryos was also inspected by HPLC analysis. The HCY injected at different position of embryos could result in heart and neural tube defects, which included ectopia cardis, hydropericardium, endocardial cushion defect, encephalocele, microcephaly, abnormal flexions and so on. HCY could apparently disturb embryonic cell cycle, suppress the synthesis of DNA and RNA of embryonic cells. Excessive apoptotic cells in brain and heart were observed in HCY\|treatment groups. It was discovered that mitochondrial damage could be described as an early event in cellular apoptosis of chick embryos. After 8 mumol of HCY was placed on the inner shell membrance, there was an obvious increase of plasma HCY concentration with a peak value of 80.58 mumol/L in 120 min, and followed by declining. On the other hand, 5 micrograms of folic acid given simultaneously with HCY could sharply curtail the rise in plasma HCY. It is concluded that HCY is a cytotoxin, inducing over apoptosis of embryos in some areas, which is coincident with the pathologic changes of neural system and heart. These findings show that there is a close relationship among HCY, apoptosis and birth defect in developing chick embryos. Mitochondrial dysmorphosis may be an important early event of apoptosis in embryos after exposure to HCY.

关键词：碘缺乏控制碘营养状况调查儿童