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排序方式: 共有775条查询结果,搜索用时 109 毫秒
1.
Various process alternatives and designs of using a filter containing cellular adsorbents to remove trace viral contaminants from blood and other protein solutions have been studied. Sterilization charts have been developed that can be used to estimate the filter size required to achieve a desired sterilization criterion. A parametric study was carried out to identify various process parameters that may affect this physical trace removal process. It has been demonstrated that the adsorption rate constant is a critical parameter in the design of an efficient cellular filter for viral contaminant removal. This constant is characteristic of the virus-cell system under consideration and is shown to be particularly sensitive to the cell surface receptor density, adsorbent diameter, and fluid flow rate. Higher log titer reduction in virus concentrations can be achieved with low flow rates and no recycle. Preliminary analyses indicate the feasibility of using a magnetically stabilized fluidized filter (MSFF) reactor design for effective virus removal from these complex solutions. 相似文献
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L.C. Chiang H.Y. Hsiao M.C. Flickinger L.F. Chen G.T. Tsao 《Enzyme and microbial technology》1982,4(2):93-95
The capabilities of immobilized Fusarium oxysporum f. sp. lini, Mucor sp., and Saccharomyces cerevisiae in fermenting pentose to ethanol have been compared. S. cerevisiae was found to have the best fermentation rate on d-xylulose of 0.3 g l?1 h?1. By using a separate isomerase column for converting d-xylose to d-xylulose and a yeast column for converting d-xylulose to ethanol, an ethanol concentration of 32 g l?1 was obtained from 10% d-xylose. The ethanol yield was calculated to be 64% of the theoretical yield. 相似文献
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Marcio Voloch Michael R. Ladisch Victor W. Rodwell George T. Tsao 《Biotechnology and bioengineering》1981,23(6):1289-1296
Fermentation of xylose by Klebsiella pneumoniae (ATCC 8724) producers meso and nonmeso 2,3-butaneodiol. The enzyme Kinetic of 2,3-butanediol stereoisomer formation from acetone is currently under study in our laboratory. Modeling of these kinetics requires resolution of meso and racemic 2,3-butanediol and positive identification of these resolved components. We report their resolution by aqueous liquid chromatography on both an analytical and a preparative scale. The resolved stereoisomer were identified by a combination of gas chromatography, gas chromatography/mass spectroscopy, 13C-NMR spectroscopy, optical activity, and, melting points of the m-dinitrobenzoyl eaters of meso and racemic 2,3-butanediol. An aqueous liquid chromatographic technique for resolving and qualifying major components of a butanediol fermentation mixture in 40 min is presented. 相似文献
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NGF and other growth factors induce an association between ERK1 and the NGF receptor, gp140prototrk.
As detected by coimmunoprecipitation from PC12 cells, NGF induces rapid association between ERK1 (a growth factor-activated serine/threonine protein kinase) and gp140prototrk NGF receptors. In contrast, no such association is found with the closely related ERK2. Anti-trk immunocomplexes generated from NGF-treated cells also contain protein kinase activity that shares many properties with soluble ERK1. The association of both ERK1 protein and ERK-like kinase activity with gp140prototrk is maximal by 5 min of NGF treatment, persists for approximately 1 hr, and subsequently declines by 18 hr. Treatment with either basic fibroblast growth factor, epidermal growth factor, or orthovanadate also leads to association of ERK1 with gp140prototrk without tyrosine phosphorylation of the latter. The interaction between ERK1 and gp140prototrk may prove relevant to the NGF mechanism. 相似文献
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Bradley P. Coe Kelsie L. Thu Sarit Aviel-Ronen Emily A. Vucic Adi F. Gazdar Stephen Lam Ming-Sound Tsao Wan L. Lam 《PloS one》2013,8(8)
Small cell lung cancer (SCLC) is a highly aggressive lung neoplasm with extremely poor clinical outcomes and no approved targeted treatments. To elucidate the mechanisms responsible for driving the SCLC phenotype in hopes of revealing novel therapeutic targets, we studied copy number and methylation profiles of SCLC. We found disruption of the E2F/Rb pathway was a prominent feature deregulated in 96% of the SCLC samples investigated and was strongly associated with increased expression of EZH2, an oncogene and core member of the polycomb repressive complex 2 (PRC2). Through its catalytic role in the PRC2 complex, EZH2 normally functions to epigenetically silence genes during development, however, it aberrantly silences genes in human cancers. We provide evidence to support that EZH2 is functionally active in SCLC tumours, exerts pro-tumourigenic functions in vitro, and is associated with aberrant methylation profiles of PRC2 target genes indicative of a “stem-cell like” hypermethylator profile in SCLC tumours. Furthermore, lentiviral-mediated knockdown of EZH2 demonstrated a significant reduction in the growth of SCLC cell lines, suggesting EZH2 has a key role in driving SCLC biology. In conclusion, our data confirm the role of EZH2 as a critical oncogene in SCLC, and lend support to the prioritization of EZH2 as a potential therapeutic target in clinical disease. 相似文献
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A. Aitmambetov A. M. Tokhtybaeva R. T. Tlegenov L. Tsao 《Russian Journal of Bioorganic Chemistry》2006,32(4):402-403
Interaction of 7-hydroxyisoflavonones with cinnamoyl chloride results in cinnamoyloxyisoflavonones. 相似文献
10.
Shutian Tao Shaoling Zhang Rong Tsao Marie Thérèse Charles Raymond Yang 《Archives Of Phytopathology And Plant Protection》2013,46(16):1564-1578
Six selected antioxidants (catechin, quercetin-3-galactoside, cyanidin-3-glucoside, pelargonidin-3-glucoside, ellagic and gallic acids) were evaluated in vitro for their antifungal activities and mode of action on Botrytis cinerea Pers., one of the most important pathogens of strawberries. Inhibitory effects were found for all the tested antioxidants, but varied at different fungal developmental stages. Catechin and quercetin-3-galactoside showed linear inhibitory effects on germ tube elongation, with the highest suppression ratios of 54.8% and 58.8% respectively. No significant effect was found on spore germination between treatments and control. Gallic acid showed very strong and linear inhibition on spore germination (r = ?0.95), but the effect diminished after spore germination. Cyanidin-3-glucoside and pelargonidin-3-glucoside provided effective control on the fungi as concentrations increased. The arresting effect of ellagic acid on development of B. cinerea was quadratic. Ellagic acid inhibited germ tube elongation and mycelial growth at its highest and lowest concentrations, while no effects were observed at its medium concentration used in this study. 相似文献