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中国的遗传学研究——遗传学进步推动中国西部经济与社会发展——2011年中国遗传学会大会

作者： LI Wei-Ye,WANG Yi-Quan key laboratory of the Ministry of Education for Subtropical Wetland Ecosystem Research,School of Life sciences xiamen university,xiamen,china,361005

Epigonichtys and Asymmeron are genera of *** there is a dispute about their *** DNA is generally considered to be a powerful genetic marker in taxonomic *** date,complete mtDNAs of 8 cephalochordate species are available including Branchostoma floridae,***,***,***,Epigonichthys maldivensis,Asymmetron lucayanus,*** and *** *** the present investigation, we sequenced the complete mitochondrial DNA of Epigonichtys cultellus and compared the mitochondrial genomes of nine lancelet species to clarify the taxonomic status of the *** mtDNA of Epigonichtys cultellus also contains 13 protein-coding genes,22 tRNA genes and 2 rRNA genes,and has the same gene order as most other lancelets except Asymmetron species. P-distance of amino acid sequences was calculated using MEGA and phylogeny tree of amino acid was constructed using neighbor-joining method with Poisson correction *** average genetic distance of protein sequences within genera Branchostoma,Epigonichtys and Asymmeron is distinctly smaller than that between any two *** phylogenetic analysis based on concatenated amino acid sequences revealed distinct genetic gaps among the three *** data from the mitochondrial genome comparison demonstrated that Epigonichtys and Asymmeron should be two separated lancelet genera.

关键词： lancelet Epigonichtys cultellus Epigonichtys Asymmeron mitochondrial genome taxonomy

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Computational properties of a new horizontal staggered grid

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Science china Earth sciences 2005年第9期48卷 1559-1568页

作者： LIU YudiState key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china Institute of Meteorology, PLA university of Science and Technology, Nanjing 211101, china 1. State key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Ph Chinese Academy of Sciences 100029 Beijing China 2. Institute of Meteorology PLA University of Science and Technology 211101 Nanjing China

This paper presents a new horizontal staggered grid (LE grid), which defines h at a gridpoint, and both u and v at the same mid-gridpoint along the x and y directions. A general method is used to deduce the dispersion relationships of describing inertia gravity waves on LE grid and Arakawa A―E grids, which are then compared with the analytical solution (AS) in re- solved or under-resolved cases, using two-order central difference or four-order compact differ- ence scheme from the frequency and group velocity. Results show that in both resolved and under-resolved cases, no matter whether two-order central difference or four-order compact dif- ference scheme is used, the frequency and group velocity discrete errors on LE grid in describing inertia gravity waves are smaller than those of Arakawa A―E grids. At the same time, it is only on LE or Arakawa grid C that the employment of a compact difference scheme of higher difference precision can improve their accuracy in describing inertia gravity waves. However, as for the other four grids (Arakawa A,B,D and E), when the difference precision increases, the accuracy of simulating inertia gravity waves decreases.

关键词： horizontal staggered grid, inertia gravity wave, LE grid, Arakawa A-E grid, compact difference scheme, central difference.

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Inhibitory effect of 2-Hydroxy-4-isopropylbenzaldehyde on the activity of mushroom tyrosinase

Inhibitory effect of 2-Hydroxy-4-isopropylbenzaldehyde on th...

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第七届全国酶学学术讨论会

作者： SONG Kang-Kang, CHEN Qing-Xi The key laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life sciences, xiamen university, xiamen 361005, china

Tyrosinase(EC 1.***.18.1) is known to be a key enzyme in melanin biosynthesis, involved in determining the color of mammalian skin and hair. Therefore, tyrosinase inhibitors have been established as important constituents of depigmentation agents. In this paper, salinaldehyde (a);cuminaldehyde (b) and 2-hydroxy-4-isopropylbenzaldehyde (c) were used as the samples to discuss the inhibitory effect on the activity of mushroom tyrosinase. The IC50 values for these three compounds were determined to be 75 μM, 2850μM and 12.5 μM, respectively, when L-3,4-dihydroxyphenylalanine (L-DOPA) was used as substrate. The inhibition kinetics analyzed indicated that compound (a) is a competitive inhibitor, compound (b) is an uncompetitive inhibitor of the tyrosinase. But the compound (c) shows mixed-type mechanism to the enzyme. The results were given in Table 1 for comparison. The result was analyzed that hydroxyl group at the ortho position of the aldehyde group contributed to highly inhibition activity, been seemed to form a quasi-six-membered ring with the nitrogen atom of the amino group through intramolecular hydrogen bonding. The Schiff base is largely governed by those factors affecting the stability of the carbon-nitrogen double bond. The electron-donating groups such as isopropyl at the para position seem to act not only by the inductive effect but to stable to the binding sites in the enzyme. So compound (c) was the most potent inhibitor of these three compouds. Compound (a) and (b) inhibit mushroom tyrosinase in different ways. Compound (a) competitively bind to the active site in the enzyme with substrate and is competitive inhibitor which only binds the free enzyme. Compound(b) only binds the ES complex rather than the free enzyme, contributing to uncompetitive inhibitory effect. And compound (c) consisted of hydroxyl group at the ortho position and isopropyl group at the para position, so it can combine with both free enzyme and enzyme-sustrate complex. It displayed co

关键词： mushroom tyrosinase 2-bydroxy-4-isopropylbenzaIdehyde inhibition kinetics

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Purification and characterization of chymotrypsin from the hepatopancreas of hybrid Tilapia(Oreochromis niloticus×***)

Purification and characterization of chymotrypsin from the h...

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饲用酶制剂开发与应用技术交流研讨会

作者： Zhi-Xing Gao,Qing-Xi Chen,Qin Wang~* key laboratory of the Ministry of Education for Coastal and Wetland Ecosystems,School of Life sciences, xiamen university,xiamen 361005,china

A chymotrypsin was isolated from the hepatopancreas of hybrid Tilapia,by acetone precipitation,ammonium sulfate fractionation,Sephacryl S-200 gel filtration and DEAE-32 ion exchange *** molecular mass of chymotrypsin was approximately 26.0 KDa by SDS - PAGE and its isoelectric point was about *** optimum pH and temperature of the enzyme were determined to be 8.0 and 50℃using N-Succinyl-L-phenylalanine p-nitroanilide(Suc-Phe-pNA) as substrate,*** proteinase displayed high stabiliy at temperature below 50℃and in the pH range from 7.5 to *** purified enzyme was effectively inhibited by the general serine protease inhibitor phenyl methyl sulphonyl fluoride(PMSF),and also by the specific chymotrypsin inhibitor N-p-tosyl-L-phenylalanine chloromethyl ketone(TPCK).This proteinase digested chromogenic substrate Suc-Phe-pNA with K,V and K(?),values of 2.2 mmol/L,7.5×10μmol/(L·min) and 325 *** proteinase was slightly activated by some metal ions such as Ca,Mg,Mn and Co,while inhibited by Zn,Cu,Al and *** ions of Li,Na,K,Cd and Ba showed to be little effect on the enzyme.

关键词： Purification Characterization Chymotrypsin Hepatopancrcas Hybrid Tilapia

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Phase Conjugation by Degenerate Four-wave Mixing in Nematic Liquid Crystals

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Chinese Journal of Lasers 1997年第5期B6卷 403-408页

作者： ZHONG Xiaoxia WU Jiada CHEN Shuchao WU Changzheng LI Fuming (State key Joint Lab for Materials Modification by Laser, Ion and Electron Beams Department of Physics, Fudan university, Shanghai 200433, chinaDepartment of Physics xiamen university, xiamen 3 Fudan Univ Shanghai China

Phase conjugation by degenerate four-wave mixing(DFWM) due to the optically induced molecular reorientation in nematic liquid crystals(NLC) is studied, and an analytical expression for the efficiency of phase conjugation is presented. Calculations of the efficiency are given for 5CB liquid crystal for further investigstion of the dependences of the phase conjugation on the angle between the pump beam and the probe beam as well as on the angle between the plane of the incident beams and the nematic director n. The physical mechanism is also discussed.

关键词： nematic liquid crystal four-wave mixing phase conjugation

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Isoform Characteristics of Human Serum Transferrin Revealed using Several analytical Techniques

Isoform Characteristics of Human Serum Transferrin Revealed ...

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第六届全国化学生物学学术会议

作者： LianZhong Luo,HongWei Jin,HeQing Huang~1 School of Life sciences xiamen university,xiamen 361005,china

＜正＞Carbohydrate-deficient transferrin（CDT） is used as a specific biomarker of alcohol abuse and frequently used as an example in legal ***,high accuracy detection of CDT is *** to interference by both genetic variants and congenital disorders of glycosylation,there is still no effective method with a diagnostic value of 100%sensitivity and ***,we developed a combined method for detecting CDT with high *** polyacrylamide gel electrophoresis was employed to extract human transferrin（HTf） with high purity from human serum previously saturated with *** phase high performance liquid chromatography（RP-HPLC）, anion exchange chromatography,matrix-assisted laser desorption/ionization time-of-flight mass spectrometry,isoelectric focusing（IEF）,and peptide mass fingerprinting（PMF） techniques were then used to detect both CDT and isoforms of *** results indicated that the detection of CDT in HTf was both sensitive and dependable with this combined method using RP-HPLC and IEF-PMF, indicating that this approach might be superior to immunoassay for the detection of CDT during clinical diagnosis.

关键词： HTf RP-HPLC CDT MALDI-TOF MS IEF Anion Exchange Chromatography.

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Fabrication of 1D Au@SiO2 Nanoparticle Chains with Lanthanide Complex on Its Backbone

Fabrication of 1D Au@SiO2 Nanoparticle Chains with Lanthanid...

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第三十五届国际光谱会议

作者： J.P.Lai L.M.Yu Y.B.Zhao~* Department of Chemistry and the key laboratory of analytical sciences of the Ministry of Education,College of Chemistry and Chemical Engineering,xiamen university,xiamen 361005,china

Au nanoparticles coated with silica were successfully fabricated into 1D nanochains with a bi-functional groups compound,2,6-dicarboxylicpydine(DCP).The spherical Au nanoparticles were initially prepared by citrate reduction method with a diameter about 18 nm and then coated by a 4 nm silica shell with amino functionalized *** Au@SiO nanoparticles were interconnected in to chains with DCP by forming amide

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Fluorescent Core-shell Silica Nanoparticles as Functionable Precursors:Towards Multicolor and Multifunctional Nanoprobes

Fluorescent Core-shell Silica Nanoparticles as Functionable ...

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第三十五届国际光谱会议

作者： C.L.Wu J.Q.Hong X.Q.Guo Y.B.Zhao~* Department of Chemistry and the key laboratory of analytical sciences of the Ministry of Education College of Chemistry and Chemical Engineering xiamen university xiamen 361005 china

＜正＞Rational design of functional nanoparticles has attracted a great deal of attention in multiplex bioanalysis and multifunctional ***,we have proposed a post-encoding concept[1]to the design and preparation of encoding fluorescent probes, which makes the preparation process of multicolor fluorescent spheres rather laborsaving

关键词：

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Study on the Structure of Mangrove Polyflavonoid Tannins with NMR and MALDI-TOF Mass Spectrometry

Study on the Structure of Mangrove Polyflavonoid Tannins wit...

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第四届中国红树林学术会议

作者： Liang-Liang Zhang a, b, Yi-Ming Lin a, b a key laboratory of Ministry of Education for Coast and Wetland Ecosystems, xiamen 361005, b Department of Biology, School of Life sciences, xiamen university, xiamen 361005

The properties of polyflavonoid tannins from the mangrove species depend on their structure in terms of monomer units, their mean degree of polymerization and the linkage-type between flavan-3-ol units with a considerable range of structural variation. Polyflavonoid tannins were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry （MALDI-TOF MS）, which were too difficult to be resolved by other techniques. MALDI-TOF mass spectra of poly?avonoid tannins of four mangrove species in Rhizophoraceae, Kandelia candel, Ceriops tagal, Bruguiera cylindrica and Rhizophora apiculata showed as follows: （1） procyanidin oligomers formed by catechin/epicatechin, and catechin-3-O-rhamnoside monomers were present in great proportions;epigallocatechin and epicatechin gallate monomers were not detected;（2） the doubly linked structure of A-type procyanidins were also evident from the mass spectra of K. candel;（3） there were major differences in polyffavonoid tannin structure among mangrove species;and （4） the distribution of tannin oligomers, and the number-average degree of polymerization obtained by MALDI-TOF MS appeared to compare well with the results obtained by 13C nuclear magnetic resonance （NMR） analysis.

关键词： Mangrove Polyflavonoids MALDI Mass spectrometry NMR

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事件诱发电位信号分类的时空特征提取方法

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生物化学与生物物理进展 2011年第9期38卷 866-871页

作者：黄志华李明泓马原野周昌乐厦门大学智能科学与技术系厦门361005 厦门大学福建省仿脑智能系统重点实验室厦门361005 福州大学数学与计算机科学学院福州350108 昆明医学院基础医学院昆明650031 中国科学院昆明动物研究所昆明650223

准确对事件诱发电位(ERPs)进行分类,对于各种人类认知研究和临床医学评估非常有意义.由于ERPs信号是非常高维的数据,而且其中包含非常多的与分类无关的信息,从ERPs信号中提取特征尤显重要.分析了共空间模式(CSP)的原理和不足,引入自回归... 详细信息

准确对事件诱发电位(ERPs)进行分类,对于各种人类认知研究和临床医学评估非常有意义.由于ERPs信号是非常高维的数据,而且其中包含非常多的与分类无关的信息,从ERPs信号中提取特征尤显重要.分析了共空间模式(CSP)的原理和不足,引入自回归(AR)模型与白化变换相结合,提出了针对ERPs分类的时空特征提取方法,并设计了验证该方法的认知实验,在认知实验数据上分别用时空特征提取方法与CSP提取特征,用同样的分类器支持向量机(SVM)训练分类器,比较它们的分类效果.实验表明,在ERPs分类问题上,时空特征提取方法与CSP相比具有明显的优势,在参数确定合理的情况下,时空特征提取方法可使分类准确率达到90%以上.

关键词： ERPs信号分类时空特征提取法共空间模式支持向量机

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