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鲢酶解物对羟自由基的清除作用

水产学报 2004年第1期28卷 93-99页

作者：许庆陵曾庆祝朱莉娜崔铁军大连水产学院农业部海洋水产增养殖学与生物技术重点开放实验室大连水产学院食品工程系大连水产学院生命科学与技术学院大连水产学院生命科学与技术学院辽宁大连 116023 大连水产学院生命科学与技术学院辽宁大连 116023

通过测定酶解物对Fenton体系产生的羟自由基的清除效果,从胰蛋白酶、木瓜蛋白酶、胃蛋白酶、枯草杆菌蛋白酶和复合蛋白酶5种酶中,筛选出木瓜蛋白酶和胰蛋白酶作为酶解鲢制备具有较高清除羟自由基活性酶解物的理想水解酶;用正交试验L9（3... 详细信息

通过测定酶解物对Fenton体系产生的羟自由基的清除效果,从胰蛋白酶、木瓜蛋白酶、胃蛋白酶、枯草杆菌蛋白酶和复合蛋白酶5种酶中,筛选出木瓜蛋白酶和胰蛋白酶作为酶解鲢制备具有较高清除羟自由基活性酶解物的理想水解酶;用正交试验L9（34）对两种酶的水解条件进行了优化,并对最佳酶解条件下得到的酶解物进行Sephadex G-25凝胶柱分离,洗脱液分别在波长280nm处比色,测定酶解物中主要抗氧化活性肽的分子量分布。结果表明,木瓜蛋白酶在温度50℃、酶解时间15min、pH=6.5、酶质量分数1.50％、底物:水=1:2的水解条件下,酶解物对羟自由基清除效果较好,清除率为88.2％;胰蛋白酶在温度55℃、酶解时间60min、pH=8.0、酶质量分数0.25％、底物:水=1:2的水解条件下,酶解物对羟自由基清除效果较好,清除率为84.2％。木瓜蛋白酶酶解物在最大洗脱峰时有最大羟自由基清除率峰,清除率为95.1％,在最大峰处酶解物中活性肽的分子量为2.2kDa;胰蛋白酶酶解物在最大洗脱峰时也有最大羟自由基清除率峰,其清除率为89.6％,该峰处活性肽的分子量为14.2kDa。

关键词：鲢酶解活性肽羟自由基抗氧化

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二级光线跟踪的并行计算

浙江大学学报（工学版） 2012年第10期46卷 1796-1802,1809页

作者：杨鑫许端清赵磊杨冰浙江大学计算机学院浙江杭州310027 大连理工大学计算机学院辽宁大连116023

基于图形处理器(GPU)体系架构研究二级光线跟踪技术,使其交互式地绘制出真实感极强的图像.基于二级光线的特性和GPU体系结构的特点,提出以下技术:具有高并行度的加速结构快速构造方法;二级光线包的自适应生成方法;自适应的并行光线跟踪... 详细信息

基于图形处理器(GPU)体系架构研究二级光线跟踪技术,使其交互式地绘制出真实感极强的图像.基于二级光线的特性和GPU体系结构的特点,提出以下技术:具有高并行度的加速结构快速构造方法;二级光线包的自适应生成方法;自适应的并行光线跟踪算法;面向优化带宽使用的数据动态管理方法等.实验表明,该方法可以最大限度地发挥图形处理器强大的并行计算能力,有效地使用硬件计算资源和存储资源,从而大大地加快二级光线跟踪的并行计算.

关键词：二级光线跟踪加速结构并行自适应性图形处理器(GPU)

A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(college of life science,Sichuan university,Chengdu 610064,china) (college of life science Sichuan University Chengdu 610064 China)

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to china that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.

PEGylated PLGA Nanoparticles as Tumor Ecrosis Factor-α Receptor Blocking Peptide Carriers:Preparation,Characterization and Release in vitro

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Journal of Wuhan university of technology(Materials science) 2007年第1期22卷 112-116页

作者：刘卫杨祥良 college of life science and technology Huazhong University of Science and Technology

To assess the merits of PEGylated poly （lactic-co-glycolic acid）（PEG-PLGA） nanoparticles as drug carriers for tumor necrosis factor-α receptor blocking peptide （TNFR-BP）, PEG-PLGA copolymer, which could be used to prepare the stealth nanoparticles, was synthesized with methoxypolyethyleneglycol, DL-lactide and glycolide. The structure of PEG-PLGA was confirmed with ^1H-NMR and FT-IR spectroscopy, and the molecular weight （MW） was determined by gel permeation chromatography. Fluorescent FITC-TNFR- BP was chosen as model protein and encapsulated within PEG-PLGA nanoparticles using the double emulsion method. Atomic force microscopy and photon correlation spectroscopy were employed to characterize the stealth nanoparticles fabricated for morphology, size with polydispersity index and zeta potential. Encapsulation efficiency （EE） and the release of FITC-TNFR-BP in nanopartieles in vitro were measured by the fluorescence measurement. The stealth nanoparticles were found to have the mean diameter less than 270 nm and zeta potential less than -20 mV. In all nanoparticle formulations, more than 45% of EE were obtained. FITC-TNFR-BP release from the PEG-PLGA nanoparticles exhibited a biphasic pattern, initial burst release and consequently sustained release. The experimental results show that PEG-PLGA nanoparticles possess the potential to develop as drug carriers for controlled release applications of TNFR-BP.

关键词： tumor necrosis factor-α receptor blocking peptide PEG-PLGA stealth nanoparticles ring-opening polymerization controlled and sustained drug release

Variations in Laboratory-Scale Actinomycete Communities Exposed to Cadmium as Assessed by Denaturing Gradient Gel Electrophoresis Profiles

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Pedosphere 2010年第2期20卷 174-184页

作者： YUAN Hai-Ping,MIN Hang 2,LIU Ji,YAN Bo and L Zhen-Mei college of life science,Zhejiang university,Hangzhou 310058 (china) college of life science Zhejiang University Hangzhou 310058 (China)

The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various con- centrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction （PCR） using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCR- amplified products, as measured by denaturing gradient gel electrophoresis （EGGE）, was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index （H） analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavallable Cd concentration and H values existed in the samples from weeks 2 （R = 0.929, P 〈 0.05） and 4 （R = 0.909, P 〈 0.05）. These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.

关键词： denaturing gradient gel electrophoresis genes principal component analysis Shannon-Weaver diversity index

Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 college of Information & Control, Nanjing university of Information science & technology, Nanjing 210044, china 2 college of Automation Engineering, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china college of Information & Control Nanjing University of Information Science & Technology Nanjing China college of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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science china(Technological sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2 & XU WeiSheng 2 1 college of Hydraulic and Environmental Engineering,china Three Gorges university,Yichang 443002,china 2 college of Hydropower Engineering,Xi’an university of technology,Xi’an 710048,china college of Hydraulic and Environmental Engineering China Three Gorges University Yichang China college of Hydropower Engineering Xi’an University of Technology Xi’an China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

NMDA and AMPA receptors mediate intracellular calcium increase in rat cortical astrocytes

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Acta Pharmacologica Sinica 2004年第6期25卷 12-18页

作者： Bo HU, Sheng-gang SUN2, E-tang TONGNeurology Department, Union Hospital, Tongji college, Huazhong university of science and technology, Wuhan 430022, china Neurology Department Union Hospital Tongji College Huazhong University of Science and Technology Wuhan 430022

AIM: To study the effect of glutamate on the intracellular calcium signal of pure cultured rat astrocytes and the roleof N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) re-ceptors in the procedure. METHODS: The fluorescence of calcium was measured by Fura-2/AM (F345/F380).RESULTS: L-Glutamate induced [Ca2+]i increase in most of the cells in concentration- and time-dependent *** 50 mmol/L induced the fluorescence increase by almost three to four times, while the effect of AMPA 50mmol/L was just half of that of D-(-)-2-amino-5-phosphonopentanoic acid (D-AP-5; a selective antagonist of theNMDA receptor). 6-Cyano-7-nitroquinoxaline-2,3-dione (CNQX, a selective antagonist of the AMPA receptor)abolished the effects of NMDA and AMPA, respectively. D-AP-5 and CNQX simultaneously or respectively attenu-ated the effect of L-glutamate at different degrees, but could not abolish it entirely. CONCLUSION: Glutamatemodulated intracellular Ca2+ of pure cultured rat astrocytes through different pathways. The activation of NMDAand AMPA receptors took part in the complex mechanisms.

关键词： glutamate astrocytes NMDA receptors AMPA receptors calcium

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang college of Information science and technology,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china college of Information science and technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2D fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2D FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform