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581.
Mitsuhiro Wada Megumi Kira Hirotsugu Kido Rie Ikeda Naotaka Kuroda Toshiaki Nishigaki Kenichiro Nakashima 《Luminescence》2011,26(3):191-195
A semi‐micro flow injection analysis (SMFIA) method for evaluation of quenching effect of food additive antioxidants or health foods on peroxynitrite (ONOO‐) is described. The injected sample was carried with phosphate buffer containing NaNO2, mixed with a trigger solution to generate ONOO‐ and then detected CL generated after mixing with luminol solution. Selective chemiluminescence caused by ONOO‐ in this generation system was confirmed by catalase treatment. Ascorbic acid (ASA), Trolox and ascorbyl palmitate (ASP) were used as food additive antioxidants. EC50 values of ASA, Trolox and ASP were 2.6, 6.4 and 43 µg/mL, respectively. The amount of reagents required for an assay by this SMFIA system could reduce the time by a third compared with the conventional method previously reported. Furthermore, as an application of the proposed method, the quenching effect of commercially available Noni (Morinda citrifolia) juices was evaluated. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
582.
Journal of Plant Research - How perennial grass populations are maintained in different climates is poorly understood at the level of individual shoots (ramets). During the years 1982–1987... 相似文献
583.
Kento Ishii Hirotsugu Fujitani Yuji Sekiguchi Satoshi Tsuneda 《Environmental microbiology》2020,22(6):2365-2382
Oxidation of nitrite to nitrate is an important process in the global nitrogen cycle. Recent molecular biology-based studies have revealed that the widespread nitrite-oxidizing bacteria (NOB) belonging to the genus ‘Candidatus Nitrotoga’ may be highly important for the environment. However, the insufficient availability of pure Nitrotoga cultures has limited our understanding of their physiological and genomic characteristics. Here, we isolated the ‘Ca. Nitrotoga’ sp. strain AM1P, from a previously enriched Nitrotoga culture, using an improved isolation strategy. Although ‘Ca. Nitrotoga’ have been recognized as cold-adapted NOB, the strain AM1P had a slightly higher optimum growth temperature at 23°C. Strain AM1P showed a pH optimum of 8.3 and was not inhibited even at high nitrite concentrations (20 mM). We obtained the complete genome of the strain and compared the genome profile to five previously sequenced ‘Ca. Nitrotoga’ strains. Comparative genomics suggested that lactate dehydrogenase may be only encoded in the strain AM1P and closely related genomes. While the growth yield of AM1P did not change, we observed faster growth in the presence of lactate in comparison to purely chemolithoautotrophic growth. The characterization of the new strain AM1P sheds light on the physiological adaptation of this environmentally important, but understudied genus ‘Ca. Nitrotoga’. 相似文献
584.
Tetsuro Fujita Yoshio Takeda Eiji Yuasa Akio Okamura Tetsuro Shingu Toshio Yokoi 《Phytochemistry》1982,21(4):903-905
From the leaves of Rabdosia inflexa a new cytotoxic diterpenoid, inflexinol was isolated, together with the known inflexin, and the structure was established as ent-kaur-16-en-15-one-1α,3α,6β,11β-tetraol 1,3-diacetate. 相似文献
585.
M. Nakamura Zhi-qiang Zhang Liang Shan Tomoyuki Hisa Mitsuyo Sasaki Ryuichi Tsukino Toyoharu Yokoi Akio Kaname Kennichi Kakudo 《Human genetics》1996,99(1):38-41
Evidence from cDNA cloning has shown that calcitonin receptors (CTRs) have seven potential transmembrane domains. In this
study, structural analysis of CTRs from ten cultured human tumor cell lines and 117 human blood samples demonstrated allelic
variants at the 1377th nucleotide in intracellular domain 4, expressing either proline or leucine as the 463rd amino acid.
It was found that the variant with proline at this site was the more prevalent type of CTR among the Japanese population.
Received: 21 June 1996 相似文献
586.
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588.
A Miyake S Mochizuki H Yokoi M Kohda K Furuichi 《The Journal of biological chemistry》1999,274(35):25018-25025
A cDNA encoding a novel voltage-gated K(+) channel protein was isolated from human brain. This protein, termed BEC1, is 46% identical to rat elk in the ether-à-go-go K(+) channel family. The BEC1 gene maps to the 12q13 region of the human genome. Northern blot analysis indicates that BEC1 is exclusively expressed in human brain, where the expression is concentrated in the telencephalic areas such as the cerebral cortex, amygdala, hippocampus, and striatum. By in situ hybridization, BEC1 is detected in the CA1-CA3 pyramidal cell layers and the dentate gyrus granule cell layers of the hippocampus. Specific signals are also found in neocortical neurons. Transfection of mammalian L929 and Chinese hamster ovary cells with BEC1 cDNA induces a voltage-gated outward current with a fast inactivation component. This current is insensitive to tetraethylammonium and quinidine. Additionally, a second related gene BEC2 was isolated from human brain. BEC2 is also brain-specific, located in the neocortex and the striatum, and functional as a channel gene. Phylogenetic analysis indicates that BEC1 and BEC2 constitute a subfamily, together with elk, in the ether-à-go-go family. The two genes may be involved in cellular excitability of restricted neurons in the human central nervous system. 相似文献
589.
T Fujita N Sugimoto F Yokoi Y Ohtsubo M Ikutoh Y Kato Y Natsuhara S Oka I Yano 《Microbiology and immunology》1990,34(6):523-532
The immunomodifying activity of a novel mycoloyl glycolipid, trehalose 2,3,6'-trimycolate (GaGM), from a unique psychrophilic acid-fast bacterium, Rhodococcus aurantiacus, was examined. ICR mice were primed intravenously (i.v.) or intraperitoneally (i.p.) with liposomes containing GaGM (300 micrograms/mouse), and were administered LPS dissolved in saline (25 micrograms/mouse, i.v.) 2 weeks later. Two hours after injection of LPS, interferons (IFNs) and tumor necrosis factor (TNF) were induced significantly in mice sera. The increase in activities of IFNs and TNF was approximately paralleled with granuloma formation in spleen of mice primed with GaGM. However, IFNs and TNF were not induced either in mice primed with GaGM but not elicited with LPS, or in those primed with GaGM and elicited by GaGM. Both activities induced were lower in mice primed with trehalose mono- or dimycolate from R. aurantiacus (GaTMM, GaTDM) or TDM from Nocardia rubra than in GaGM-primed mice. Time course study showed that the maximum activity of each interferon (alpha, beta, or gamma) was observed at different stages after LPS administration; IFN-alpha, IFN-beta, and IFN-gamma appeared 3, 2, and 6 hours most abundantly after LPS administration, respectively. 相似文献
590.
Biopolymer flocculant produced by an Pseudomonas sp. 总被引:13,自引:0,他引:13
Haruhiko Yokoi Takashi Yoshida Jun Hirose Sachio Hayashi Yoshiyuki Takasaki 《Biotechnology Techniques》1998,12(7):511-514
A biopolymer flocculant produced by Pseudomonas sp. A-99 had flocculating activity both in inorganic suspensions containing Ca2, Mg2 or Fe3 and in organic suspensions containing Fe2, Fe3 or Al3. The flocculant was an acidic protein and contained a small amount of an acidic polysaccharide consisting of galacturonic acid, glucose and galactose. Productivity of the flocculant was about 450 mg/l medium. © Rapid Science Ltd. 1998 相似文献