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Structure of polysaccharides from mycelium and culture medium of Phellinus nigricans using submerged fermentation

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Science china(Life Sciences) 2008年第6期51卷 513-519页

作者： LI Xia, JIAO LiLi, ZHANG Xu, TIAN WenMin, CHEN Shan & ZHANG LiPing school of Life Sciences, Northeast Normal university, Changchun 13002.,{2. school of Life Sciences Northeast Normal University Changchun China

Two water-soluble polysaccharides, PNW1 and PNM1, were respectively isolated from the mycelium and its culture medium of Phellinus nigricans using submerged fermentation before determining their effects on inhibiting the growth of transplantable tumors in mice. The results of the pharmaceutical experiments showed that oral administration of PNW1 and PNM1 (at a dose of 400 mg/kg) inhibited the growth of tumor of mice-transplanted Sarcoma 180 in vivo. Moreover, a higher inhibition ratio of PNW1 (74.70%) was obtained as compared with PNM1 (55.84%). The averaged molecular weight of PNW1 and PNM1 was determined to be 33 and 2. kD, respectively. Both PNW1 and PNM1 were consisted of glu- cose, galactose, mannose, arabinose and fucose. The major structural features of PNW1 and PNM1 were elucidated using partial acid hydrolysis, periodate oxidation, Smith degradation, 13C-NMR, me- thylation and GC-MS. On the basis of these results, the repeating units of PNW1 and PNM1 were estab- lished.

关键词： Phellinus nigricans polysaccharide chemical structure

Upregulation of Mark3 and Rpgripl mRNA expression by jujuboside A in mouse hippocampus

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Acta Pharmacologica Sinica 2007年第3期 334-338页

作者： Cheng WANG Zi-li YOU~2.Qing XIA Tao XIONG Yang XIA De-zhong YAO school of Life Science and Technology university of Electronic Science and Technology of{2.,Chengdu 610054,china

Aim:To investigate the effect of jujuboside A(JuA)on modulating gene expres-sion in the ***:The spontaneous activity of mice wasmonitored,and the differential display polymerase chain reaction was adapted toscreen differentially-expressed genes modulated by JuA in the mouse ***:JuA significantly decreased the total activity intensity(P<0.01 vs control)at a dosage of 80 mg/kg,and the genes MAP/microtubule affinity-regulatingkinase3(Mark3)and retinitis pigmentosa GTPase regulator interacting protein l(Rpgripl)were upregulated by JuA in the mouse ***:JuAhad an inhibitory effect on the spontaneous activity of the mice,and JuA regu-lated the transcription of Mark3 and Rpgripl in the mouse hippocampus.

关键词： jujuboside A hippocampus DD-PCR Mark3 Rpgrip1

Friction and wear properties of copper matrix composites reinforced by tungsten-coated carbon nanotubes

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Rare Metals 2011年第6期30卷 657-663页

作者： NIE Junhui JIA Xian JIA Chengchang LI Yi ZHANG Yafeng SHI Na school of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China china Iron ＆ Steel Research Institute Group Beijing 100081 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

Carbon nanotubes （CNTs） were coated by tungsten layer using metal organic chemical vapor deposition process with tungsten hexacarbonyl as a precursor. The W-coated CNTs （W-CNTs） were dispersed into Cu powders by magnetic stirring process and then the mixed powders were consolidated by spark plasma sintering to fabricate W-CNTs/Cu composites. The CNTs/Cu composites were fabricated using the similafprocesses. The friction coefficient and mass wear loss of W-CNTs/Cu and CNTs/Cu composites were studied. The results showed that the W-CNT content, interfacial bonding situation, and applied load could influence the friction coefficient and wear loss of W-CNTs/Cu com- posites. When the W-CNT content was 1.0 wt.%, the W-CNTs/Cu composites got the minimum friction coefficient and wear loss, which were decreased by 72.1% and 47.6%, respectively, compared with pure Cu specimen. The friction coefficient and wear loss of W-CNTs/Cu composites were lower than those of CNTs/Cu composites, which was due to that the interracial bonding at （W-CNTs）-Cu interface was better than that at CNTs-Cu interface. The friction coefficient of composites did not vary obviously with increasing applied load, while the wear loss of composites increased significantly with the increase of applied load.

关键词： carbon nanotubes tungsten layer copper friction coefficient wear loss

Magnetic particles and cadmium sulfide nanoparticles tagging for signal-amplifying detection of nucleic acids

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Science china Chemistry 2011年第8期54卷 1304-1310页

作者： DONG XiaoYa, ZHAO WeiWei, XU JingJuan & CHEN HongYuan State Key Laboratory of Analytical Chemistry for Life Science school of Chemistry and Chemical Engineering, Nanjing university, Nanjing 2.0093,{2. State Key Laboratory of Analytical Chemistry for Life Science school of Chemistry and Chemical Engineering Nanjing University Nanjing China

A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magnetic particles (MNPs) for the immobilization of linker DNA and CdS NPs and the subsequent target DNA hybridization. Using the unique characteristic of nicking endonuclease for cutting one specific strand of double strand DNA (ds DNA), the linker DNA could be transected and the target DNA could be liberated for re-hybridization and hence the amount of released CdS NPs was enhanced. Due to the advantage of the MNPs and signal amplification from the target recycling, the analyte DNA could be detected by the square-wave stripping voltammetry (SWV) in a wide linear range from 0.4 fM to 100 fM with the detection limit down to 0.08 fM. The proposed DNA detection strategy possesses high sensitivity, satisfactory reproducibility and excellent stability, which might have potential in other DNA biological assays.

关键词： CdS nanoparticles square wave stripping voltammetry nicking endonuclease electrochemical DNA assay

Effect of excessive Internet use on the time-frequency characteristic of EEG

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Progress in Natural Science:Materials International 2009年第10期19卷 1383-1387页

作者： Hongqiang Yu,Xin Zhao,Ning Li,Mingshi Wang,Peng Zhou school of Precision Instruments and Optoelectronics Engineering,Tianjin university,Tianjin 300072.{2. school of Precision Instruments and Optoelectronics Engineering Tianjin University Tianjin 300072 China

We examined the effect of excessive Internet use on the time-frequency characteristic of the electroencephalogram by wavelet trans-formed and non-negative matrix factorization(NMF).The event-related potentials(ERP) of normal subjects and excessive Internet users were acquired using the oddball paradigm *** applied the wavelet transformed and event-related spectral perturbation to ERP in order to extract the time-frequency *** F-test statistics of time-frequency values were then decomposed into two com-ponents by *** Internet use resulted in a significant decrease in the P300 amplitudes(P<0.05) and a significant increase in the P300 latency(P < 0.05) in all *** major effect of excessive Internet use on gamma oscillation occurred at 300 ms after stimuli at 40-50 Hz on the parietal central ***,these data suggest that excessive Internet use affects information coding and integration in the brain.

关键词： NMF ERSP Gamma oscillation Event-related potentials(ERP)

THE RESEARCH OF TRADITIONAL TOTEM ART IN THE PRODUCT DESIGN

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THE RESEARCH OF TRADITIONAL TOTEM ART IN THE PRODUCT DESIGN

SEDIMENTARY ORGANIC MATTER’S CLASSIFICATION AND OIL-GENERATING MODELS FOR ORGANIC COMPONENTS OF OIL-GAS SOURCE ROCKS IN china

2.06年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： WANG Lili, YANG Zheng school of Urban Design, wuhan {2., wuhan 430072. china

The totem art has varieties in the form of expression and symbol significance. This article aims to explore the application of totem art in product design. In the first part, the article emphasize the

关键词： The totem art product design product symbol.

来源： cnki会议评论

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Scientia Geologica Sinica 1997年第4期 44-49页

作者： Jin Kuili, Liu Dameng and Yao Suping Beijing graduate school,{2. university of Mining and Technology, Beijing 100083

ＳＥＤＩＭＥＮＴＡＲＹＯＲＧＡＮＩＣＭＡＴＴＥＲ’ＳＣＬＡＳＳＩＦＩＣＡＴＩＯＮＡＮＤＯＩＬＧＥＮＥＲＡＴＩＮＧＭＯＤＥＬＳＦＯＲＯＲＧＡＮＩＣＣＯＭＰＯＮＥＮＴＳＯＦＯＩＬＧＡＳＳＯＵＲＣＥＲＯＣＫＳＩＮＣＨＩ... 详细信息

ＳＥＤＩＭＥＮＴＡＲＹＯＲＧＡＮＩＣＭＡＴＴＥＲ’ＳＣＬＡＳＳＩＦＩＣＡＴＩＯＮＡＮＤＯＩＬＧＥＮＥＲＡＴＩＮＧＭＯＤＥＬＳＦＯＲＯＲＧＡＮＩＣＣＯＭＰＯＮＥＮＴＳＯＦＯＩＬＧＡＳＳＯＵＲＣＥＲＯＣＫＳＩＮＣＨＩＮＡＪｉｎＫｕｉｌｉ，ＬｉｕＤａｍ...

关键词： OIL-GAS OF SOURCE COMPONENTS china AND

Robust Estimation of Variance Components Model

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Systems Science and Systems Engineering 1996年第4期6卷 500-504页

作者： MA Chaoqun XUAN Jiaji(International Business school of Human university, Hunan, 410082.{2.)

The classical least-squares methods may only solve LS β when the variance-covariance (matrix ∑(σ2. ∑)) is known (σ2. is unknown and ∑ is known) in linear model. The author thinks that maximum likelihood type estimation (M-estimation) should replace LS estimation. The paper discusses robust estimations of parameter vector and variance components for corresponding error model based on the principle of maximum likelihood type estimations (M-estimations). The influence functions are given respectively.

关键词： robust estimation variance components general functional model

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民主·宪政民主及其低度程序法则

现代法学 2004年第3期26卷 20-25页

作者：江国华武汉大学湖北武汉430072

人是民主的目标,任何意义的民主都与人的生活方式有关;政府是民主的载体,民主是引领政府走向人道的唯一方法。民主政治的核心程序是竞争性的选举,但选举仅仅是一种低度的民主形式。宪政民主乃民主体制与宪政主义的有机结合,使它得以运... 详细信息

人是民主的目标,任何意义的民主都与人的生活方式有关;政府是民主的载体,民主是引领政府走向人道的唯一方法。民主政治的核心程序是竞争性的选举,但选举仅仅是一种低度的民主形式。宪政民主乃民主体制与宪政主义的有机结合,使它得以运转的低度程序法则,正是现代政府合法性的低度标准。

关键词：民主政治宪政建设低度民主程序政治体制选举制度