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981.
从等价电子组态的"自旋因式化"出发,导出了nsN~nhN组态的Lα、Lβ取值规则,给出了推求等价电子组态光谱项的简易方法. 相似文献
982.
Ru2 and Ru encode mouse orthologs of the genes mutated in human Hermansky-Pudlak syndrome types 5 and 6 总被引:12,自引:0,他引:12
Zhang Q Zhao B Li W Oiso N Novak EK Rusiniak ME Gautam R Chintala S O'Brien EP Zhang Y Roe BA Elliott RW Eicher EM Liang P Kratz C Legius E Spritz RA O'Sullivan TN Copeland NG Jenkins NA Swank RT 《Nature genetics》2003,33(2):145-153
Hermansky-Pudlak syndrome (HPS) is a genetically heterogeneous disease involving abnormalities of melanosomes, platelet dense granules and lysosomes. Here we have used positional candidate and transgenic rescue approaches to identify the genes mutated in ruby-eye 2 and ruby-eye mice (ru2 and ru, respectively), two 'mimic' mouse models of HPS. We also show that these genes are orthologs of the genes mutated in individuals with HPS types 5 and 6, respectively, and that their protein products directly interact. Both genes are previously unknown and are found only in higher eukaryotes, and together represent a new class of genes that have evolved in higher organisms to govern the synthesis of highly specialized lysosome-related organelles. 相似文献
983.
Lipophilic tea polyphenols (LTP) were prepared by catalytic esterifieation of green tea polyphenols (GRIP) with hexadeeanoyl chloride. A novel long-chain aeyl-derivative of epigalloeateehin-3-o-gallate(EGCG) was first isolated from purification of LTP by high-speed eountereurrent ehromatography (HSCCC)using a solvent system composed of n-hexane-ethyl acetate-methanol-water ( 1 : 1 : 1 : 1, v/v) . The moleeularstructure of the acyl-derivative, Epigallocatechin-3-O-gallate-4‘-O-hexadeeanate , was elucidated by meansof elemental analysis, IR, 1H-NMR and MS spectra. 相似文献
984.
“愉快教育”被中外教育家们认为是当今教育应达到的最高境界。本文仅就愉快教育理论的原则在教学实践中的体现略陈管窥之见,以期抛砖引玉。 相似文献
985.
洪涝灾害是长江中游地区最为严重的自然灾害.本文叙述了以遥感和地理信息的应用为基础,将多元资料复合^[1],快速、准确与全天候的对长江中游地区水灾进行监测的方法.介绍了RS和GIS支持下建立起来的监测系统的目标、技术路线、结构流程等,并进行了应用分析.以期利用高新技术手段为长江中游地区有关部门快速了解灾情、指定救灾方案和灾后重建提供决策支持. 相似文献
986.
All organisms with oxygenic photosynthesis contain two photosystems:photosystem Ⅰ(PSⅠ)and photo-systemⅡ(PSⅡ),The minimal photosystem Ⅱ particles which are photochemically active contain three subunits:D1,D2 and cytochrome b559 (Cyt b559),The function of Cyt b559 remains unclear,We have successfully overxpressed the psbF gene,encoding the β subunit of Cyt b559,from a marine cyanobacterium Synechoccous sp.PCC 7002 as a fusion gene and obtained a redox-active from of Cyt b559,When the N-terminal GST protein of the fusion gene product was removed with thrombin ,the PsbF protein was still redox-active,suggesting that the recombinant PsbF can form dimer in Escherichia coli.The absorption spectra of either the oxidized from or the reduced form of both GST fusion protein and the purified PsbF dimer and the difference Spectra between the two forms are the same as that of the Cyt b559 isolated from the higher plants .Redox titration analysis of recombinant PsbF showed that the mid-point redox potential of the recombinant Cyt b559 was approximately 50 mV, which is close to the low potential of Cyt b559 ,The results are helpful to the understanding of locatlization and function of Cyt b559 on thylakoid membranes.Ⅰ 相似文献
987.
WANGTiejun QIYingqun XUJingkun HUXiujie CHENPing 《科学通报(英文版)》2003,48(22):2444-2445
By mixing various concentrations of poly (ethylene glycol), a series of poly(3,4-ethylenedioxythiophene)-poly(styeenesuffonate) composite thin films were prepared.The electrical conductivity of the PEDOT-PSS/PEG thin films was measured by the four-pcobe method. Experimental results showed that the inclusion of poly(ethylene glycol) influenced the electrical conductivity of PEDOT-PSS film significantly. With the increase of PEG concentrations, the electrical conductivity sharply increased to reach a maximum and then slowly decreased down. Furthermore, the PEG molecular weight and environment temperature also played important roles on the electrical conductivity of PEDOT-PSS/PEG thin films. A good linear relationship was found between in σDC and T^-1/2 within the entire temperature range detected. 相似文献
988.
QTL mapping of the root traits and their correlation analysis with drought resistance using DH lines from paddy and upland rice cross 总被引:8,自引:0,他引:8
MUPing LIZichao LIChunping ZHANGHongliang WUChangming LIChen WANGXiangkun 《科学通报(英文版)》2003,48(24):2718-2724
A Double Haploid (DH) population, 116 plants, derived from the cross between Japonica upland rice IRAT109 and paddy rice Yuefu, planted in PVC pipe under upland ecosystem in 2001 and 2002, was used in this study. Seven root traits, including basal root thickness (BRT), total root number (RN), maximum root length (MRL), root fresh weight (RFW), root dry weight (RDW), ratio of root fresh weight to shoot fresh weight (RFW/SFW) and ratio of root dry weight to shoot dry weight (RDW/SDW), were studied. Using index of drought resistance (IDR), the ratio of yield under upland ecosystem to yield under lowland ecosystem of DH lines, as the criteria of drought resistance, and correla-tion analysis between root traits and IDR, showed that BRT, MRL and RN were significantly correlated with IDR. High IDR lines had thicker BRT, longer MRL and less RN than low IDR lines. A molecular linkage map with 94 RFLP markers and 71 SSR markers covering 1535.1 cM was pro-duced. QTLs and G譋 interactions for BRT, RN, MRL, RFW, RDW, RFW/SFW and RDW/SDW were obtained based on the constructed molecular linkage map and soft-ware QTLmapper version 1.0. A total of 18 additive QTLs and 18 pairs of epistatic QTLs associated with root traits were detected. There were nine additive QTLs and two pairs of epistatic QTLs performed significant interactions with environment. Some QTLs with high general contribution and no G譋 interaction were obtained. Two pairs of epistatic QTLs mrl3 and mrl8, brt3 and brt11a controlling MRL and BRT had high general contributions of 21.51% and 13.03% respectively. An additive QTL and a pair of epistatic QTLs controlling RFW and RDW had high general contributions of 13.50% and 25.64% respectively. Marker assisted selec-tion (MAS) for rice drought resistance based on QTL with high general contribution, low G譋 interaction and tightly linkage with IDR were also discussed. 相似文献
989.
水稻花培育种技术操作和无性系变异体选择 总被引:3,自引:0,他引:3
概述了水稻花培育种的技术操作程序和细胞无性系变异的选择方法。选择合适的水稻花培起始材料,选用适宜的培养基配方,对于水稻花培中愈伤组织诱导和分化至关重要。某些增效因子(例如水解乳蛋白、单核苷酸、AgNO3等)可提高灿稻花培的绿苗分化率。无性系变异为农作物细胞工程育种提供丰富的选择材料。通过对细胞变异的研究,建立了裸米选择-测米培胚的技术方法,并选育出多个高蛋白量的水稻优质品种(品系)。 相似文献
990.