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1.
The activity and inhibition of poly(ADP‐ribose) polymerase‐1 in equine peripheral blood mononuclear cells in vitro 下载免费PDF全文
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Journal of Plant Diseases and Protection - A broad range of different Fusarium (F.) species is associated with Fusarium head blight (FHB) on barley and the corresponding negative effects in... 相似文献
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Guy Honée Guido F. J. M. Van den Ackerveken Henk W. J. Van den Broek Ton J. Cozijnsen Matthieu H. A. J. Joosten Mirian Kooman-Gersmann Jacques Vervoort Ralph Vogelsang Paul Vossen Jos P. Wubben Pierre J. G. M. De Wit 《Euphytica》1994,79(3):219-225
The fungus Cladosprium fulvum is a biotrophic leaf pathogen of tomato. The fungus develops in the intercellular space without forming specialized feeding structures and does not affect the leaf tissue. The outcome of the C. fulvum-tomato interaction can be described by the gene-for-gene model. Failure of infection is expressed by a hypersensitive response. Two fungal proteins, ECP1 and ECP2, have been isolated and their corresponding genes have been cloned. In a compatible interaction including many physiological races ECP1 and ECP2 are highly produced and a role in pathogenicity is suggestive. The ecp1 gene shows some homology with tumor necrosis factor receptors (TNFRs) while the ecp2 gene shows no homology with sequences known in data bases. However, disruption of one of the two genes showed no reduced pathogenicity of the fungus. Two race-specific elicitors, AVR4 and AVR9, have been isolated and their corresponding genes have been cloned. The avirulence genes Avr4 and Avr9 are only present in C. fulvum avirulent on Cf-4 and Cf-9 cultivars, respectively. The expression of these two genes is, like the expression of the ecp genes, highly induced when the fungus grows in planta. Disruption of the Avr9 gene in wild type avirulent races leads to virulence on tomato genotypes carrying the complementary resistance gene Cf-9. A single base-pair change in the avirulence gene Avr4 leads to virulence on tomato genotypes carrying the Cf-4 resistance gene. Isolation, characterization and possible function of ECP1, ECP2, AVR4, and AVR9 will be discussed. 相似文献
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the mortality of the grain weevil,Sitophilus granarius, treated with methyl bromide at 25° and 30°C is influenced by the relative humidity. The concentrationtime product for a mortality of 90% increases significantly with humidity. 相似文献
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Bunzel M Ralph J Kim H Lu F Ralph SA Marita JM Hatfield RD Steinhart H 《Journal of agricultural and food chemistry》2003,51(5):1427-1434
Two 8-8-coupled sinapic acid dehydrodimers and at least three sinapate-ferulate heterodimers have been identified as saponification products from different insoluble and soluble cereal grain dietary fibers. The two 8-8-disinapates were authenticated by comparison of their GC retention times and mass spectra with authentic dehydrodimers synthesized from methyl or ethyl sinapate using two different single-electron metal oxidant systems. The highest amounts (481 microg/g) were found in wild rice insoluble dietary fiber. Model reactions showed that it is unlikely that the dehydrodisinapates detected are artifacts formed from free sinapic acid during the saponification procedure. The dehydrodisinapates presumably derive from radical coupling of sinapate-polymer esters in the cell wall; the radical coupling origin is further confirmed by finding 8-8 and 8-5 (and possibly 8-O-4) sinapate-ferulate cross-products. Sinapates therefore appear to have an analogous role to ferulates in cross-linking polysaccharides in cereal grains and presumably grass cell walls in general. 相似文献
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Dorfner R Ferge T Kettrup A Zimmermann R Yeretzian C 《Journal of agricultural and food chemistry》2003,51(19):5768-5773
The formation of 4-vinylguaiacol, guaiacol, and phenol during coffee roasting was monitored in real-time, using resonance enhanced multiphoton ionization and time-of-flight mass spectrometry. A model is proposed, based on two connected reaction channels. One channel, termed the "low activation energy" channel, consists of ester hydrolysis of 5-FQA followed by decarboxylation of the ferulic acid to form 4-vinylguaiacol, and finally polymerization at the vinyl group to form partly insoluble polymers (coffee melanoidins). The second "high activation energy" channel opens up once the beans have reached higher temperatures. It leads to formation of guaiacol, via oxidation of 4-vinylguaiacol, and subsequently to phenol and other phenolic VOCs. This work aims at developing strategies to modify the composition of coffee flavor compounds based on the time-temperature history during roasting. 相似文献
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The factors influencing the number of nightjars on 36 heathland sites (referred to as patches) in Dorset, England were examined using novel spatial integration of existing datasets. Surrogate measures of human density and settlement, including the amount of developed land at different distances from the heath (obtained from aerial photographs) and the actual number of buildings (obtained from Post Code databases) were all found to be highly correlated with each other and to show a strong negative relationship with the density of nightjars present on a patch, regardless of patch size. The amount of woodland (the preferred foraging habitat) surrounding each patch (within 500 m of the patch boundary) was also a significant predictor of nightjar numbers. When used together, the extent of woodland and developed land both gave significant improvements to predictions of nightjar density. The results indicate that the number of nightjars present on a heathland patch is influenced by the surrounding land-use and that the effect of urban development is more than just habitat loss. We suggest that trends identified are at least partly due to actual human presence on the heathlands and as such, human disturbance is potentially a problem for this species. 相似文献