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941.
Seventeen kenaf varieties collected from several regions around Asia and Europe were grown in Korea and their genetic diversity was analyzed using morphological characters and AFLP technique. In the morphological analysis, the 17 varieties were divided into two major groups according to stem diameter, plant height, and flowering periods. The late varieties, which could yield more biomass compared with the early-medium varieties, were included in one of two major groups. Nonetheless, it is difficult to identify individual varieties based on morphological characters because of their limited variation. For the AFLP analysis, 34 primer combinations generated a total of 3,193 polymorphic bands (out of 3,914) with a polymorphic rate of 82%. The clusters were divided into two major groups with a similarity coefficient of 0.63 by UPGMA analysis method; but each group did not show a common tendency. Additionally, the results of the AFLP analysis did not show similar tendency compared with morphological data, a result that might be explained in terms of convergent evolution, i.e. the acquisition of morphologically similar traits between distinctly unrelated varieties.  相似文献   
942.
Cereal seed storage proteins are encoded by complex multigene families and their subunit profiles are highly related to end-use qualities. Each fraction of albumin and hordein was extracted and its subunit profile was evaluated in related to malt and grain quality parameters. The purpose of this study was to provide selection criteria for high quality malting barley using grain and malt quality parameters and biochemical-genetic information. Grain and malt quality of 13 local adaptability test (LAT) lines were evaluated for malting process. A total of 16 germplasm accessions of high or low seed storage protein content were also evaluated for biochemicalgenetic analysis. The correlation coefficients among quality parameters were analyzed. Several important quality parameters in brewing process showed significant positive or negative correlations. Seed storage protein subunits of albumin and hordein of all tested lines and accessions were evaluated using 12% 1D SDS-PAGE. Scored data of protein subunit’s presence or absence was applied to Agglomerative Hierarchical Clustering (AHC) for statistical analysis and showed specific grouping patterns among tested lines. Clustered lines with subunit information were highly related with agricultural performance and grain and malt qualities. Based on the profiles of seed storage protein subunits, association of hordein subunit of 38, 43, and 65 kDa with high malt scored lines was found. The obtained results would provide improved selection criteria for high quality malting barley in the malting barley breeding program.  相似文献   
943.
Chen YH  Tai CY  Hwang TL  Weng CF  Li JJ  Fang LS  Wang WH  Wu YC  Sung PJ 《Marine drugs》2010,8(12):2936-2945
Two new eunicellin-type diterpenoids, cladielloides A (1) and B (2), which were found to possess a 2-hydroxybutyroxy group in their structures, were isolated from an Indonesian octocoral identified as Cladiella sp. The structures of eunicellins 1 and 2 were elucidated by spectroscopic methods. Cladielloide B (2) exhibited moderate cytotoxicity toward CCRF-CEM tumor cells and this compound displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils.  相似文献   
944.
We report on the preparation and electrical characterization of nylon-6 nanofibers via electrospinning technique. During electrospinning, the polymer solution became highly ionized and emerging out of the micro-tip syringe by forming mesh-like ultrafine nanofibers structure in between the main fibers. The resultant nylon-6 nanofibers were well-oriented with uniform structure. The diameter of the ultrafine nanofibers (7 to 40 nm) is one order less than those of main fibers (100 to 200 nm). The current-voltage (I-V) measurements revealed a linear curve with an occurrence of negative differential resistance (NDR) behavior. The existence of NDR region in the nylon-6 nanofibers can be attributed to the tunneling current through the ultrafine structures. The fabrication of nanofibers, in the form of ultrafine mesh-like form, is relatively fast and inexpensive, and it paves the way to build up of new dimension for nano device applications.  相似文献   
945.
Kim YC  Lee MK  Sung SH  Kim SH 《Fitoterapia》2007,78(3):196-199
Investigation of antiinflammatory constituents of the stem and root barks of Ulmus davidiana var. japonica resulted in the isolation of three guaiane type sesquiterpenes, torilin, 1-hydroxytorilin, together with a new derivative, (1beta, 7beta, 8beta, 10beta)-1,8,11-trihydroxy-4-guaien-8-angeloyl-3-one named 1-hydroxytorilin A. All the three sesquiterpenes inhibited lipopolysaccharide-induced nitric oxide production in murine microglial BV2 cells.  相似文献   
946.
Two strains of Azadinium poporum, one from the Korean West coast and the other from the North Sea, were mass cultured for isolation of new azaspiracids. Approximately 0.9 mg of pure AZA-36 (1) and 1.3 mg of pure AZA-37 (2) were isolated from the Korean (870 L) and North Sea (120 L) strains, respectively. The structures were determined to be 3-hydroxy-8-methyl-39-demethyl-azaspiracid-1 (1) and 3-hydroxy-7,8-dihydro-39-demethyl-azaspiracid-1 (2) by 1H- and 13C-NMR. Using the Jurkat T lymphocyte cell toxicity assay, (1) and (2) were found to be 6- and 3-fold less toxic than AZA-1, respectively.  相似文献   
947.
Plant lectins have attracted much attention for biomedical applications including targeted drug delivery system and therapy against tumors and microbial infections. The main problem of using lectins as a biomedical tool is a batch-to-batch variation in isoforms content. The production of lectins using recombination tools has the advantage of obtaining high amounts of proteins with more precise properties, but there are only a handful of functional recombinant lectins presently available. A fetuin/asialo-fetuin specific lectin, Rhodobindin, has unique tandem repeats structure which makes it useful in exploiting for recombinant lectin. We developed three functional recombinant lectins using E. coli expression system: one from full cDNA sequence and two from fragmentary sequences of Rhodobindin. Hemagglutinating activity and solubility of the recombinant lectins were highest at OD 0.7 cell concentration at 20 °C. The optimized process developed in this study was suitable for the quality-controlled production of high amounts of soluble recombinant lectins.  相似文献   
948.
Five new 13,14-epoxybriarane diterpenoids, briarenolides U–Y (1–5), were isolated from the octocoral Briareum sp. The structures of briaranes 1–5 were elucidated by spectroscopic methods. Briarenolides U–Y (1–5) were found to significantly inhibit the expression of the pro-inflammatory inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein of the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells.  相似文献   
949.
950.
We prepared long carbon fiber (LCF)-reinforced thermoplastic composites using a compatibilizer of itaconic acid grafted polypropylene (PP-g-IA). We confirmed the structure of PP-g-IA and investigated the compatibilizing effects of PPg- IA on LCF/polypropylene composites. The tensile strength, tensile moduli, flexural strength, and flexural moduli of the composites increased with increasing PP-g-IA content in the thermoplastic composites. Using single pull-out analyzing system, we found PP-g-IA improved interfacial strength between the carbon fiber and PP matrix. The thermal properties of the composites were measured by thermogravimetric analysis (TGA). We could observe that LCF enhanced the mechanical properties and thermal decomposition temperature of the polypropylene (PP) composites, compared with neat PP. The fractured surfaces of PP/PP-g-IA/LCF composites showed that PP-g-IA was effective for improving the interfacial adhesion between LCF and PP matrix.  相似文献   
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