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GRAFT COPOLYMERIZATION OF ACRYLAMIDE ONTO POLY（N-PARA-TOLYLACRYLAMIDE） FILMS INITIATED BY CERIC ION

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chinese Journal of Polymer Science 1988年第1期6卷 75-83页

作者：丘坤元宋叶 Department of Chemistry Peking university beijing

Functional monomers having phenylcarbamoyl and p-tolylcarbamoyl were synthesized. Binary initiation system consisted of Ce4. and these functional monomers could initiate acrylamide polymerization. It was found that acrylamide could graft copolymerize onto macromolecules having these functional monomers units. The formation of graft copolymer has been verified by its percentage of water absorption, contact angle with water, XPS and SEM photographs. The reaction mechanism was proposed and the main reactive site of graft ocpolymerization initiated by Ce4. would take place predominantly at the functional pendant group.

关键词： Acrylamide Functional monomers N-para-tolylacrylamide Copolymers Graft copolymerization initiated by ceric ion Characterization of grafted copolymers by SEM XPS.

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黄土沟壑区小流域土地利用变化及驱动力分析

山地学报 2006年第1期24卷 27-32页

作者：李志刘文兆杨勤科梁伟李双江甘卓亭王锐王兵中国科学院水利部水土保持研究所中国科学院水利部水土保持研究所陕西杨凌712100 中国科学院研究生院北京10003. 西北农林科技大学资源环境学院

小流域综合治理是黄土高原减少土壤侵蚀和发展经济的成功经验。作为黄土高原沟壑区的典型代表,王东沟流域的土地利用变化反映了流域治理的过程。利用其1986、1994.2004.的土地利用数据,研究了该区18 a间的土地利用变化规律,探究土地... 详细信息

小流域综合治理是黄土高原减少土壤侵蚀和发展经济的成功经验。作为黄土高原沟壑区的典型代表,王东沟流域的土地利用变化反映了流域治理的过程。利用其1986、1994.2004.的土地利用数据,研究了该区18 a间的土地利用变化规律,探究土地利用变化的驱动力,并使用GM(1,1)灰色模型对王东沟流域未来的土地利用变化趋势进行了分析。结果表明:1986~2004.间王东沟流域各土地利用类型变化的面积大小依次是农地>果园>林地>非生产地>草地,就土地利用类型的变化速度而言,依次为果园>农地>林地>非生产地>草地;以1994.为界将1986~2004.划分为两个时期,两个时期的土地利用变化规律有所不同;利用矢量图叠加,发现1994.2004.流域4..4.%的土地发生了土地类型的变化,土地利用变化类型主要有9种,农地转出的类型和林地转入的类型占多数;社会经济驱动、人为积极治理和政策导向是王东沟流域土地利用变化的主要驱动力;GM(1,1)趋势分析表明在今后一段时间内,影响因子不变的前提下,果园面积仍有增加趋势,农地面积需要进行人工调控以保持一定的规模。

关键词：王东沟流域土地利用动态变化驱动力GM(1,1)

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白皮松种子发芽习性及其种源变异的研究

林业科学 1989年第2期25卷 97-105页

作者：李晓洁徐化成中国林业科学研究院林业研究所北京林业大学

我们从形态与生化组成、休眠习性以及发芽要求三方面研究了山西临汾和陵川、甘肃徽县、四川江油四个不同种源白皮松种子的变异情况,发现种子大小和千粒重以及脂肪酸与氨基酸组成在种源间存在显著差异,种源间种子休眠深浅显著不同。干冷... 详细信息

我们从形态与生化组成、休眠习性以及发芽要求三方面研究了山西临汾和陵川、甘肃徽县、四川江油四个不同种源白皮松种子的变异情况,发现种子大小和千粒重以及脂肪酸与氨基酸组成在种源间存在显著差异,种源间种子休眠深浅显著不同。干冷生境种源(临汾、陵川)种子休眠较深,比湿暖生境种源(徽县、江油)种子更能抵抗水分逆境。而温度与种源没有显著交互作用,25/20和25/15均适宜各种源种子的发芽。

关键词：白皮松种子发芽种源

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以声发射估计岩石试样先存应力的新方法

现代地质 1989年第3期3卷 359-368页

作者：丁原辰张大伦地质矿产部地质力学研究所中国地质大学

利用声发射话动的凯塞(Kaiser)效应测定岩石先存最大应力已成为声发射技术的重要应用领域。目前,判断岩石凯塞效应对应应力的方法仍被重视。作者在研究岩石在单轴压缩条件下的声发射话动时发现:除了通过凯塞效应可测定岩石的先存最大应... 详细信息

利用声发射话动的凯塞(Kaiser)效应测定岩石先存最大应力已成为声发射技术的重要应用领域。目前,判断岩石凯塞效应对应应力的方法仍被重视。作者在研究岩石在单轴压缩条件下的声发射话动时发现:除了通过凯塞效应可测定岩石的先存最大应力之外,还可根据重复加载时声发射话动的某些特点推断出加载前的先存最大应力,从而进一步验证和提高了利用凯塞效应测定先存最大应力的可靠性。重复加载时声发射话动在一定技术条件下会出现这样的特点:在应力达到第一次加载的最大应力值时出现凯塞效应;而在此之前,当应力达到加载前岩石的先存最大应力值时,声发射话动相对其前后有所特殊。作者认为,这种现象可能反映了材料对先前经历过的损伤的记忆能力。本文初步探讨了这一现象的物理基础。

关键词：凯塞( Kaiser)效应声发射先存应力地应力

MODIFIED　WEIGHTED　GRADIENT　PROJECTION　METHOD　AND　RESEARCH　TO　THE　KINEMATIC　CONTROL　OF　REDUNDANT　MANIPULATORS

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chinese Journal of Aeronautics 1996年第3期9卷 217-224页

作者： Chen Weihai Yang Zongxu Zhang Qixian(Institute for Robottes, beijing university of Aeronautics and Astronautics, beijing, China, 100083.Zhao Zhanfang(Institute for Robotics Research, beijing Institute of Technology, beijing, China, 100081) Institute for Robotics Beijing Univ. Aero. and Astronaut. Beijing 100083 China Institute for Robotics Research Beijing Institute of Technology Beijing 100081 China

To raise the optimizing ability of the redundant manipulators, a modified weighted gradient projection method(MWGPM) to optimize kinematics is *** new concepts, the matrix weightability measure(MWM) and the self-motion declinability measure(SMDM) are proposed. Thus the weighting ability of the weighting matrix and the self-motion amplitude decided by the homogeneous solution could be continuously regulated. MWGPM has the merits which belong to both the least-norm solution (WLN), and gradient projection method(GPM), and it can obtain ideal optimizing effects at low joint velocities, which has been verified by simulation.

关键词： robots kinematics optimization control

钇-90微球选择性内放射治疗肝脏恶性肿瘤规范化操作专家共识(2024.)

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中华医学杂志 2024年第7期104卷 486-498页

作者：中国医师协会介入医师分会临床诊疗指南专委会中国研究型医院学会肝胆胰外科专业委员会董家鸿滕皋军朱海东张琳贾中芝刘加成陆建不详清华大学附属北京清华长庚医院肝胆胰外科北京102218 东南大学附属中大医院介入与血管外科教育部医药基础研究创新中心南京210009 东南大学附属中大医院介入与血管外科清华大学附属北京清华长庚医院肝胆胰中心介入科南京医科大学附属常州第二人民医院介入血管科东南大学附属中大医院核医学科

钇-90微球选择性内放射治疗(^(90)Y-SIRT)肝脏恶性肿瘤已有50余年临床应用史,大规模临床应用亦超过20年,其安全性和疗效已被证实,但在我国仍处于起步阶段。^(90)Y-SIRT操作复杂,涉及多学科团队协作,对操作者要求较高,一旦发生^(90)Y微... 详细信息

钇-90微球选择性内放射治疗(^(90)Y-SIRT)肝脏恶性肿瘤已有50余年临床应用史,大规模临床应用亦超过20年,其安全性和疗效已被证实,但在我国仍处于起步阶段。^(90)Y-SIRT操作复杂,涉及多学科团队协作,对操作者要求较高,一旦发生^(90)Y微球异位分布可能会导致严重并发症。因此,规范^(90)Y-SIRT操作技术,对促进^(90)Y-SIRT在我国稳步推广至关重要。中国医师协会介入医师分会联合中国研究型医院学会肝胆胰外科专业委员会组织国内相关领域专家,基于现有文献证据并结合我国临床实践,围绕患者筛选、术前影像学评估、^(90)Y-SIRT方案、处方剂量计算、^(90)Y-SIRT的实施、术后管理、常见不良反应与并发症等,共同制订本专家共识,以规范^(90)Y-SIRT操作,保证疗效,降低并发症发生率,促进^(90)Y-SIRT在国内的推广和普及。

关键词：肝肿瘤钇-90 微球选择性内放射治疗共识

A novel inhibition of martentoxin on neuronal BK channel subtype(α +β4.and functional modulation of neural excitability

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A novel inhibition of martentoxin on neuronal BK channel sub...

Potential Selective Forces for Intron Gains and Losses in Evolution

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Jian SHI~1,Hui-Qiong HE~1,Rong ZHAO~1,Jin CHEN~1,Ying CHEN~2,Yan-Hong DUAN~2,Juan YANG~2,Lei ZHONG~2,Jian-Wei ZHANG~2,Xue-Qin SHU~2,Ping ZHENG~3.Yong-Hua JI~(2,*) 1 graduate School of the chinese academy of {3.,Institute of Physiology,Shanghai Institutes for Biological {3.,chinese academy of {3.,Shanghai,20003.,China 2 School of Life {3.,Shanghai university,Shang-Da Road 99,Shanghai,2004.4.China 3.State Key Laboratory of Medical Neurobiology,Fudan university Shanghai Medical College,Shanghai,20003.,China

Martentoxin as a 3. residues peptidyl toxin was capable of blocking large-conductance Ca-activated K(BK) channels in adrenal medulla chromaffin *** present study investigated the pharmacological discrimination of martentoxin on BK channels subtypes and implicated the physiological function of neuronal BK channels(α+β4. through the pharmacological *** results showed that the iberiotoxin-insensitive BK channels composed ofαandβ4.subunits could be potently blocked by martentoxin(IC50 =～80 nM).In contrast,the iberiotoxin-sensitive BK channel consisting of only a subunits showed a low sensitivity to *** inhibitory effect of martentoxin on BK channels(α+β4. appears with a novel interaction mode,including Ca dependence and two possible interaction sites:one for trapping and the other for ***,in vivo experiments also suggested that this subtype of BK channels was the target of ***,EEG recordings showed that the inhibition of BK channels(α+β4. by martentoxin would induce exacerbated abnormal discharges,which indicated a braking role of BK channels(α+β4. in spontaneous bursting ***,this research not only sheds light on a unique ligand for BK channels(α+β4.,but also highlights a novel model for the interaction between BK channel and neurotoxin.

关键词： BK channel martentoxin iberiotoxin insensitivity allosteric effects excitability

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mTOR enhancement of STIM1-mediated store-operated Ca2+ signaling constrains tumor development

2009年国际基因组学大会

作者： Deng-Ke Niu~* College of Life sciences beijing Normal university beijing 100875 China.

＜正＞Although accumulating evidence indicates that spliceosomal introns are integrated components of eukaryotic genes,previous theories on intron gains and losses mainly focused on the mutational processes by assuming that intron gains and losses are neutral or nearly neutral events in *** from recent advances in molecular biology,we can propose two hypotheses on the potential selective forces for intron gains and losses.（1） Organisms may benefit from intron gains by avoiding deleterious R-loops,which are cotranscriptionally formed from the nascent RNA and the double DNA strands and threaten the stability of the genome;（2） Intron losses in some organisms may be selected against because the length of exons is limited by the splicing-site-recognition mechanism:exon *** attentions should be given to potential selective forces on intron evolution,although we still do not know exactly whether intron gains and losses are neutral or *** hypotheses proposed by our group do not exclude other potential selective forces on intron gains and *** welcome further studies to test them or evidence supporting or against them.

关键词： intron gain intron loss selective force R-loop exon definition

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mTOR enhancement of STIM1-mediated store-operated Ca2+ signa...