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排序方式: 共有97条查询结果,搜索用时 15 毫秒
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Elena V. Girich Anton N. Yurchenko Olga F. Smetanina Phan Thi Hoai Trinh Ngo Thi Duy Ngoc Mikhail V. Pivkin Roman S. Popov Evgeny A. Pislyagin Ekaterina S. Menchinskaya Ekaterina A. Chingizova Shamil S. Afiyatullov Ekaterina A. Yurchenko 《Marine drugs》2020,18(12)
Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity. 相似文献
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Preckel T Fung-Leung WP Cai Z Vitiello A Salter-Cid L Winqvist O Wolfe TG Von Herrath M Angulo A Ghazal P Lee JD Fourie AM Wu Y Pang J Ngo K Peterson PA Früh K Yang Y 《Science (New York, N.Y.)》1999,286(5447):2162-2165
In vitro PA28 binds and activates proteasomes. It is shown here that mice with a disrupted PA28b gene lack PA28a and PA28b polypeptides, demonstrating that PA28 functions as a hetero-oligomer in vivo. Processing of antigenic epitopes derived from exogenous or endogenous antigens is altered in PA28-/- mice. Cytotoxic T lymphocyte responses are impaired, and assembly of immunoproteasomes is greatly inhibited in mice lacking PA28. These results show that PA28 is necessary for immunoproteasome assembly and is required for efficient antigen processing, thus demonstrating the importance of PA28-mediated proteasome function in immune responses. 相似文献
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DH Lowndes DB Geohegan AA Puretzky DP Norton CM Rouleau 《Science (New York, N.Y.)》1996,273(5277):898-903
Pulsed laser deposition (PLD) is a conceptually and experimentally simple yet highly versatile tool for thin-film and multilayer research. Its advantages for the film growth of oxides and other chemically complex materials include stoichiometric transfer, growth from an energetic beam, reactive deposition, and inherent simplicity for the growth of multilayered structures. With the use of PLD, artificially layered materials and metastable phases have been created and their properties varied by control of the layer thicknesses. In situ monitoring techniques have provided information about the role of energetic species in the formation of ultrahard phases and in the doping of semiconductors. Cluster-assembled nanocrystalline and composite films offer opportunities to control and produce new combinations of properties with PLD. 相似文献
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Serra-Majem L Ribas L Ngo J Ortega RM García A Pérez-Rodrigo C Aranceta J 《Public health nutrition》2004,7(7):931-935
OBJECTIVE: To evaluate dietary habits in Spanish children and adolescents based on a Mediterranean Diet Quality Index tool, which considers certain principles sustaining and challenging traditional healthy Mediterranean dietary patterns. DESIGN: Observational population-based cross-sectional study. A 16-item Mediterranean Diet Quality Index was included in data gathered for the EnKid study (in which two 24-hour recalls, a quantitative 169-item food-frequency questionnaire and a general questionnaire about socio-economic, demographic and lifestyle items were administered). SETTING: Spain. SUBJECTS: In total, 3850 children and youths aged 2-24 years residing in Spain. RESULTS: Of the sample, 4.2% showed very low KIDMED index results, 49.4% had intermediate values and 46.4% had high index results. Important geographical differences were seen, with subjects from the Northeast showing the most favourable outcomes (52% with elevated scores vs. 37.5% of those from the North). Lower percentages of high diet quality were observed in low socio-economic groups, compared with middle and upper income cohorts (42.8%, 47.6% and 54.9%, respectively). Large cities had more positive results and only slight variations were seen for gender and age. CONCLUSIONS: The KIDMED index, the first to evaluate the adequacy of Mediterranean dietary patterns in children and youth, confirms that this collective is undergoing important changes, which makes them a priority target for nutrition interventions. Results challenge certain commonly perceived notions tied to income level, population size and diet quality. 相似文献
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Trinh Xuan Hoat Ngo Gia Bon Mai Van Quan Vu Duy Hien Nguyen Duc Thanh Matthew Dickinson 《Phytoparasitica》2012,40(4):351-359
Sugarcane is an important cash crop in Vietnam and has been widely promoted at national and provincial level. In 2006, a new disease was discovered in sugarcane in the Nghean Tate&Lyle Sugar Mill in Nghean Province in north-central Vietnam. The key symptoms were the formation of green grassy shoots around the base of mature stools. We applied nested polymerase chain reaction (PCR) using P1/P7 and R16F2n/R16R2 for detection and characterization of phytoplasma from the symptomatic tissues. PCR products of the expected size (approx. 1200?bp) were obtained from the 16S rDNA of the phytoplasma. The restriction fragment length polymorphism profiles indicated that all samples were infected by the same phytoplasma. Phylogenetic analysis confirmed that the SCGS phytoplasma from Vietnam belong to the 16SrXI group, formerly Rice Yellow Dwarf group. 相似文献