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151.
A series of supported Ni catalysts including Ni/MgO, Ni/γ-Al2O3, Ni/α-Al2O3, Ni/SiO2 and Ni/ZrO2 was tested in CO2 reforming of toluene as a model compound of tar from biomass gasification in a fluidized bed reactor, and characterized by the means of temperature programmed reduction with hydrogen (H2-TPR), XRD, TEM and temperature programmed oxidation (TPO). Combining the characterization results with the performance tests, the activity of catalyst greatly depended on Ni particles size, and the stability was affected by the coke composition. Both of them (Ni particle size and coke composition) were closely related to the interaction between nickel and support which would determine the chemical environment where Ni inhabited. The best catalytic performance was observed on Ni/MgO due to the strong interaction between NiO and MgO via the formation of Ni-Mg-O solid solution, and the highest dispersion of Ni particle in the basic environment. 相似文献
152.
The dazzling array of basal branches in the mtDNA macrohaplogroup M from India as inferred from complete genomes 总被引:8,自引:1,他引:8
Sun C Kong QP Palanichamy MG Agrawal S Bandelt HJ Yao YG Khan F Zhu CL Chaudhuri TK Zhang YP 《Molecular biology and evolution》2006,23(3):683-690
Many efforts based on complete mitochondrial DNA (mtDNA) genomeshave been made to depict the global mtDNA landscape, but thephylogeny of Indian macrohaplogroup M has not yet been resolvedin detail. To fill this lacuna, we took the same strategy asin our recent analysis of Indian mtDNA macrohaplogroup N andselected 56 mtDNAs from over 1,200 samples across India forcomplete sequencing, with the intention to cover all Indianautochthonous M lineages. As a result, the phylogenetic statusof previously identified haplogroups based on control-regionand/or partial coding-region information, such as M2, M3, M4,M5, M6, M30, and M33, was solidified or redefined here. Moreover,seven novel basal M haplogroups (viz., M34M40) were identified,and yet another five singular branches of the M phylogeny werediscovered in the present study. The comparison of matrilinealcomponents among India, East Asia, Southeast Asia, and Oceaniaat the deepest level yielded a star-like and nonoverlappingpattern, reflecting a rapid mode of modern human dispersal alongthe Asian coast after the initial "out-of-Africa" event. 相似文献
153.
Enrichment of a common wheat genetic map and QTL mapping for fatty acid content in grain 总被引:2,自引:0,他引:2
Ying-ying Wang Xian-yin Sun Yan Zhao Fan-mei Kong Ying Guo Gui-zhi Zhang Yan-yan Pu Ke WuSi-shen Li 《Plant science》2011,181(1):65-75
DArT and SSR markers were used to saturate and improve a previous genetic map of RILs derived from the cross Chuan35050 × Shannong483. The new map comprised 719 loci, 561 of which were located on specific chromosomes, giving a total map length of 4008.4 cM; the rest 158 loci were mapped to the most likely intervals. The average chromosome length was 190.9 cM and the marker density was 7.15 cM per marker interval. Among the 719 loci, the majority of marker loci were DArTs (361); the rest included 170 SSRs, 100 EST-SSRs, and 88 other molecular and biochemical loci. QTL mapping for fatty acid content in wheat grain was conducted in this study. Forty QTLs were detected in different environments, with single QTL explaining 3.6-58.1% of the phenotypic variations. These QTLs were distributed on 16 chromosomes. Twenty-two QTLs showed positive additive effects, with Chuan35050 increasing the QTL effects, whereas 18 QTLs were negative with increasing effects from Shannong483. Six sets of co-located QTLs for different traits occurred on chromosomes 1B, 1D, 2D, 5D, and 6B. 相似文献
154.
The insulin receptor (IR) gene plays an important role in regulating cell growth, differentiation and development. In the present study, DNA sequences of insulin receptor genes, IRa and IRb, were amplified and sequenced from 37 representative species of the Cyprinidae and from five outgroup species from non-cyprinid Cypriniformes. Based on coding sequences (CDS) of tyrosine kinase regions of IRa and IRb, molecular evolution and phylogenetic relationships were analyzed to better understand the characteristics of IR gene divergence in the family Cyprinidae. IRa and IRb were clustered into one lineage in the gene tree of the IR gene family, reconstructed using the unweighted pair group method with arithmetic mean (UPGMA). IRa and IRb have evolved into distinct genes after IR gene duplication in Cyprinidae. For each gene, molecular evolution analyses showed that there was no significant difference among different groups in the reconstructed maximum parsimony (MP) tree of Cyprinidae; IRa and IRb have been subjected to similar evolutionary pressure among different lineages. Although the amino acid sequences of IRa and IRb tyrosine kinase regions were highly conserved, our analyses showed that there were clear sequence variations between the tyrosine kinase regions of IRa and IRb proteins. This indicates that IRa and IRb proteins might play different roles in the insulin signaling pathway. 相似文献
155.
Molecular tagging and mapping of the erect panicle gene in rice 总被引:6,自引:0,他引:6
Fan Na Kong Jia Yu Wang Ji Cheng Zou Li Xue Shi Min De Jin Zheng Jin Xu Bin Wang 《Molecular breeding : new strategies in plant improvement》2007,19(4):297-304
Erect panicle (EP) is one of the more important traits of the proposed ideotype of high-yielding rice. Several rice cultivars
with the EP phenotype, which has been reported to be controlled by a dominant gene, have been successfully developed and released
for commercial production in North China. To analyze the inheritance of the EP trait, we generated segregating F2 and BC1F1 populations by crossing an EP-type variety, Liaojing 5, and a curved-panicle-type variety, Fengjin. Our results confirmed that a dominant gene controls the EP trait. Simple-sequence repeat (SSR) and bulked segregant analyses
of the F2 population revealed that the EP gene is located on chromosome 9, between two newly developed SSR markers, RM5833-11 and RM5686-23, at a genetic distance
of 1.5 and 0.9 cM, respectively. Markers closer to the EP gene were developed by amplified fragment length polymorphism (AFLP) analysis with 128 AFLP primer combinations. Three AFLP
markers were found to be linked to the EP gene, and the nearest marker, E-TA/M-CTC200, was mapped to the same location as SSR marker RM5686-23, 1.5 cM from the EP gene. A local map around the EP gene comprising nine SSR and one AFLP marker was constructed. These markers will be useful for marker-assisted selection
(MAS) for the EP trait in rice breeding programs. 相似文献
156.
一种放大凋亡细胞Giemsa染色法及其在抗癌药物研究中的应用 总被引:1,自引:0,他引:1
本文介绍了一种用甲醇、冰醋酸、水处理细胞再经Giemsa染色的方法,经该方法处理后,细胞体积增大,凋亡细胞形态尤其胞核结构在普通光学显微镜下非常清晰.采用高三尖杉酯碱诱导四种不同类型肿瘤细胞凋亡,经放大细胞Giemsa染色之后,可获得清晰的不同时期凋亡细胞形态学表现及动态变化特征.进一步用琼脂糖电泳法检测四种细胞的DNA降解程度,结果表明,这种放大细胞的方法比琼脂糖电泳法更适用于形成凋亡小体之前细胞形态学特征的分析,为抗癌药物及细胞凋亡的研究提供了一种直观、准确的方法. 相似文献
157.
介绍了以基因工程为核心内容,包括细胞工程、酶工程和发酵工程的现代生物技术在改造食品资源、改进食品加工工艺,改善食品质量及开发新型保健食品等方面的应用状况,并展望了其发展前景。 相似文献
158.
159.
Kevin K.-C. Liu Bruce A. Lefker Mark A. Dombroski Phoebe Chiang Peter Cornelius Terrell A. Patterson Yuan Zeng Stephanie Santucci Elizabeth Tomlinson Colleen P. Gibbons Ravi Marala Janice A. Brown Jimmy X. Kong Eunsun Lee Wendy Werner Zane Wenzel Craig Giragossian Hou Chen Steven B. Coffey 《Bioorganic & medicinal chemistry letters》2010,20(7):2365-2369
Brain-penetrable proline amides were developed as 5HT2c agonists with more than 1000-fold binding selectivity against 5HT2b receptor. After medicinal chemistry optimization and SAR studies, orally active proline amides with robust efficacy in a rodent food intake inhibition model were uncovered. 相似文献
160.
Xinyi Wu Ruiru Cheng Shulin Xue Zhongxin Kong Hongshen Wan Guoqiang Li Yulong Huang Haiyan Jia Jizeng Jia Lixia Zhang Zhengqiang Ma 《Molecular breeding : new strategies in plant improvement》2014,33(1):129-138
The spike characteristics length, spikelet density and fertile floret number are related yield components and are important in cereal improvement. QSpl.nau-2D is a major quantitative trait locus controlling spike length (SPL) detected in the recombinant inbred line population developed by crossing wheat (Triticum aestivum) cultivars Nanda2419 with Wangshuibai. In this study, to validate its genetic effect and determine its precise location, QSpl.nau-2D’s near-isogenic line (NIL) was developed using Mianyang99-323 as the recurrent parent through marker-assisted selection. Field trials showed that the NIL not only had significantly longer spikes on average than the recurrent parent but also had significantly higher grain weight, but did not differ in spikelet number and kernel number per spike. In the F2 population derived from a cross of the NIL with Mianyang99-323, QSpl.nau-2D functioned like a single gene and conditioned the SPL in a partially dominant manner, and was thus designated as HL1 (for head length). To precisely map HL1, 89 recombinants, consisting of 11 genotypes, were identified in the NIL-derived F2 population of 674 plants by using markers in the Xwmc25–Xgpw4080 interval. Phenotyping these lines showed that the introduction of a 0.9-cM interval flanked by Xcfd53 and DG371 in Nanda2419 resulted in longer spikes and a higher grain weight in the NIL. The availability of markers closely linked to HL1 could facilitate its use in breeding programs. 相似文献