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971.
972.
Laura W. Pomeroy Jacob M. Aaronson Samuel Handelman Jori Hardman Kevin Kawalec Thomas Bitterman Ward C. Wheeler 《Cladistics : the international journal of the Willi Hennig Society》2012,28(5):483-488
We have reported previously on use of a web‐based application, Supramap ( http://supramap.org ) for the study of biogeographic, genotypic, and phenotypic evolution. Using Supramap we have developed maps of the spread of drug‐resistant influenza and host shifts in H1N1 and H5N1 influenza and coronaviruses such as SARS. Here we report on another zoonotic pathogen, H7 influenza, and provide an update on the implementation of Supramap as a web service. We find that the emergence of pathogenic strains of H7 is labile with many transitions from high to low pathogenicity, and from low to high pathogenicity. We use Supramap to put these events in a temporal and geospatial context. We identify several lineages of H7 influenza with biomarkers of high pathogenicity in regions that have not been reported in the scientific literature. The original implementation of Supramap was built with tightly coupled client and server software. Now we have decoupled the components to provide a modular web service for POY ( http://poyws.org ) that can be consumed by a data provider to create a novel application. To demonstrate the web service, we have produced an application, Geogenes ( http://geogenes.org ). Unlike in Supramap, in which the user is required to create and upload data files, in Geogenes the user works from a graphical interface to query an underlying dataset. Geogenes demonstrates how the web service can provide underlying processing for any sequence and metadata database. © The Willi Hennig Society 2012. 相似文献
973.
Cytochrome c reductase is inhibited by p-chlorophenyl-methoxybenzyl-ketoxime (CPMB-oxime). CPMB-oxime induces a red-shift of the reduced spectrum of cytochrome b. The inhibitor blocks the oxidation of ubihydroquinone at the QP center of this enzyme in a non-competitive way. The binding stoichiometry equals one inhibitor molecule per Qp center. The apparent Kd in a red-shift assay was 6.9 +/- 0.6 microM. All binding characteristics analysed in this study were very similar to those of the E-beta-methoxyacrylate inhibitors, although the chemical structure is different from these inhibitors. This result is interpreted as a support for the inhibitory mechanism based on the model of a 'catalytic switch' proposed recently for the E-beta-methoxyacrylate inhibitors (MOA-inhibitors (Brandt and von Jagow, Eur. J. Biochem. 相似文献
974.
Mutagenesis of hydroxylamine oxidoreductase in Nitrosomonas europaea by transformation and recombination. 总被引:2,自引:0,他引:2 下载免费PDF全文
Mutagenesis of Nitrosomonas europaea was achieved by electroporation and recombination. To demonstrate this, an aminoglycoside 3'-phosphotransferase (kan) gene was specifically inserted into each of the three gene copies of hao individually. Southern hybridizations and PCR analysis showed the incorporation of the kan gene at the chosen genetic loci. The isolation of mutant strains was achieved in 7 to 14 days when the strains were grown on solid medium. The induced mutations were stable even in the absence of kanamycin-selective pressure for periods of up to 45 days in culture. The mutant strains did not show an observable phenotype different from that of the wild type when grown under the same conditions. 相似文献
975.
The moving parts of voltage-gated ion channels. 总被引:32,自引:0,他引:32
G Yellen 《Quarterly reviews of biophysics》1998,31(3):239-295
976.
977.
D. V. Popov D. V. Swirkun A. I. Netreba O. S. Tarasova A. B. Prostova I. M. Larina A. S. Borovik O. L. Vinogradova 《Human physiology》2006,32(5):609-614
The study was designed to test the hypothesis that, during strength training, a restricted blood supply to the working muscles stimulates the secretion of anabolic hormones and an increase in the muscle mass and strength can be achieved with significantly lower training loads. During eight weeks, three times a week, 18 young, physically active males trained their leg extensor muscles. Nine subjects (group I) worked at 80% of the maximal voluntary contraction (MVC), whereas the rest (group II) performed their exercise without relaxation and at a lower load (50% MVC). The total training load in group II was significantly lower than in group I (77 ± 5 vs. 157 ± 7 kJ, respectively). The eight-week training of both groups significantly increased the mean maximum strength (by 35 and 21% in groups I and II, respectively) and volume (by 17 and 9%, respectively) of the muscles trained (however, the differences between the groups with respect to these changes were nonsignificant). Group I displayed a higher increase in the blood level of creatine phosphokinase than group II, while group II showed a greater increase in the blood concentration of lactate. In contrast to group I, group II displayed a significant increase in the blood concentrations of growth hormone, insulin-like growth factor 1 (IGF-1), and cortisol. Hence, the suggestion that the secretion of metabolic hormones is triggered by a metabolic, rather than mechanical, stimulus from working muscles seems plausible. 相似文献
978.
The distribution of GABAergic interneurons as well as terminal and synaptic networks in different layers of the rat sensorimotor neocortex were studied at different stages of the postnatal period under normal conditions and after exposure to perinatal hypoxia. In control animals, the architectonics of the inhibitory network in different layers of the sensorimotor neocortex was shown to display distinctive features at different stages of the postnatal development. At early postnatal stages, a significant portion of neurons in layers II–V are immunopositive for GAD-67, indicative of a high level of GABA expression, however, GABA transmission is extremely weak, thus supporting the presence in the neuropil of only sporadic GABAergic terminals and synapses. By the juvenile age, a dramatic drop in the number of GABAergic neurons and an increase in the density of the network of GABA-immunopositive processes and synaptic structures occur in the neuropil, suggesting a considerable increase in GABA transmission. A higher level of GABA transmission is revealed in layers IV and V, persisting over the prepubertal period. Our results demonstrate that acute perinatal hypoxia affects the state of the inhibitory GABAergic network in the rat sensorimotor neocortex during the postnatal period. GABA expression and transmission were shown to change virtually in all layers. 相似文献
979.
980.
5''-Nucleotidases in rat heart. Evidence for the occurrence of two soluble enzymes with different substrate specificities. 总被引:7,自引:3,他引:4 下载免费PDF全文
Chromatography of soluble proteins from rat heart on phosphocellulose columns separates two 5'-nucleotidases. The first to emerge from the column shows a preference for AMP over IMP as substrate, whereas the second shows a preference for IMP over AMP. The properties of the IMP-preferring enzyme, including the conditions under which it is eluted from phosphocellulose columns, show it to be the enzyme studied by Itoh, Oka & Ozasa [Biochem. J. (1986) 235, 847-851]. The kinetic properties of the AMP-preferring enzyme indicate that it is likely to be the enzyme responsible for the production of adenosine under conditions of hypoxia and increased work load, and with metabolic stresses such as a high load of acetate. 相似文献