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排序方式: 共有300条查询结果,搜索用时 9 毫秒
81.
Jin KK Krishna SS Schwarzenbacher R McMullan D Abdubek P Agarwalla S Ambing E Axelrod H Canaves JM Chiu HJ Deacon AM DiDonato M Elsliger MA Feuerhelm J Godzik A Grittini C Grzechnik SK Hale J Hampton E Haugen J Hornsby M Jaroszewski L Klock HE Knuth MW Koesema E Kreusch A Kuhn P Lesley SA Miller MD Moy K Nigoghossian E Okach L Oommachen S Paulsen J Quijano K Reyes R Rife C Stevens RC Spraggon G van den Bedem H Velasquez J White A Wolf G Han GW Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2006,63(4):1112-1118
82.
Guillermo Quijano María Hernandez Frédéric Thalasso Raúl Muñoz Santiago Villaverde 《Applied microbiology and biotechnology》2009,82(5):829-836
Operation of microbial electrolysis cells (MECs) without an ion exchange membrane could help to lower the construction costs
while lowering the ohmic cell resistance and improving MEC conversion rates by minimizing the pH gradient between anode and
cathode. In this research, we demonstrate that membraneless MECs with plain graphite can be operated for methane production
without pH adjustment and that the ohmic cell resistance could be lowered with approximately 50% by removing the cation exchange
membrane. As a result, the current production increased from 66 ± 2 to 156 ± 1 A m−3 MEC by removing the membrane with an applied voltage of −0.8 V. Methane was the main energetic product despite continuous
operation under carbonate-limited and slightly acidified conditions (pH 6.1–6.2). Our results suggest that continuous production
of hydrogen in membraneless MECs will be challenging since methane production might not be avoided easily. The electrical
energy invested was not always completely recovered under the form of an energy-rich biogas; however, our results indicate
that membraneless MECs might be a viable polishing step for the treatment of the effluent of anaerobic digesters as methane
was produced under low organic loading conditions and at room temperature.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
83.
Janine C. Quijano Michael J. Stinchfield Brad Zerlanko Ying Y. Gibbens Norma T. Takaesu Cathy Hyman-Walsh David Wotton Stuart J. Newfeld 《PloS one》2010,5(7)
The Sno oncogene (Snoo or dSno in Drosophila) is a highly conserved protein and a well-established antagonist of Transforming Growth Factor-β signaling in overexpression assays. However, analyses of Sno mutants in flies and mice have proven enigmatic in revealing developmental roles for Sno proteins. Thus, to identify developmental roles for dSno we first reconciled conflicting data on the lethality of dSno mutations. Then we conducted analyses of wing development in dSno loss of function genotypes. These studies revealed ectopic margin bristles and ectopic campaniform sensilla in the anterior compartment of the wing blade suggesting that dSno functions to antagonize Wingless (Wg) signaling. A subsequent series of gain of function analyses yielded the opposite phenotype (loss of bristles and sensilla) and further suggested that dSno antagonizes Wg signal transduction in target cells. To date Sno family proteins have not been reported to influence the Wg pathway during development in any species. Overall our data suggest that dSno functions as a tissue-specific component of the Wg signaling pathway with modest antagonistic activity under normal conditions but capable of blocking significant levels of extraneous Wg, a role that may be conserved in vertebrates. 相似文献
84.
JC Biro 《Theoretical biology & medical modelling》2006,3(1):15-12
Background
Prediction of protein folding and specific interactions from only the sequence (ab initio) is a major challenge in bioinformatics. It is believed that such prediction will prove possible if Anfinsen's thermodynamic principle is correct for all kinds of proteins, and all the information necessary to form a concrete 3D structure is indeed present in the sequence. 相似文献85.
Schwarzenbacher R Jaroszewski L von Delft F Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2004,55(3):768-771
86.
Spraggon G Schwarzenbacher R Kreusch A Lee CC Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Jaroszewski L Karlak C Klock HE Koesema E Kovarik JS Kuhn P Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Stevens RC van den Bedem H Velasquez J Vincent J von Delft F Wang X West B Wolf G Xu Q Hodgson KO Wooley J Lesley SA Wilson IA 《Proteins》2004,55(4):1078-1081
87.
Alfonso G. Ober Leovigildo Quijano Lowell E. Urbatsch Nikolaus H. Fischer 《Phytochemistry》1984,23(4):910-912
Chemical analysis of Calea trichomata yielded, besides four known eudesmanolides, a new eudesmanolide, trichomatolide A. The structure of the new compound was established by chemical and spectral methods. 相似文献
88.
Calea trichomata gave in addition to four known 1β-hydroxy-8β-tigloyloxy-11(13)-eudesmen-6α, 12-olide derivatives a new heliangolide, 3-deoxy 相似文献
89.
90.
Effect of insulin on ultrastructure and glycogenesis in primary cultures of adult rat hepatocytes 下载免费PDF全文
Insulin in the presence of high concentrations of glucose has a beneficial trophic effect on the development of primary cultures of hepatocytes. Compared to the situation observed in hormone-free control cultures, the flattening of the reaggregated hepatocytes is enhanced, and the reconstituted cell trabeculae are enlarged and tend to form a confluent monolayer after 3 days; the survival time is prolonged from 3 to 5 or 6 days. Ultrastructural modifications are also initiated by insulin; numerous glycogen particles appear after 24 h, in between the cisternae of the proliferated smooth endoplasmic reticulum. After 48 h, large amounts of glycogen are stored, and numerous polysomes are present. A small number of cells showed an increased synthesis of lipid droplets in the lumen of the smooth endoplasmic reticulum and form liposomes at the same time. After 72 h, cytolysomes filled with glycogen develop, simulating glycogenosis type II. Simultaneously, microtubules and microfilaments, closely related to numerous polysomes, appear in cytoplasmic extensions constituting undulating membranes. The biochemical data demonstrate that, in the absence of insulin, a high concentration of glucose stimulates glycogenesis and hinders glycogenolysis. This effect of glucose on polysaccharide synthesis is progressively lost. The addition of insulin to the culture induces after 48 and 72 h, a three- to fivefold increase of the glucose incorporation into glycogen, as compared to the controls. The presence of insulin is required to maintain the hepatocyte's capacity to store glycogen. Glycogen synthetase is converted into its active form under the influence of glucose. Insulin increases the rate of activation. 相似文献