排序方式： 共有67条查询结果，搜索用时 281 毫秒
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Mithril C Dragsted LO Meyer C Blauert E Holt MK Astrup A 《Public health nutrition》2012,15(10):1941-1947
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Wisner AL Desin TS Lam PK Berberov E Mickael CS Townsend HG Potter AA Köster W 《Veterinary microbiology》2011,153(3-4):274-284
Several structural components of the type III secretion systems (T3SS) encoded by Salmonella pathogenicity island (SPI)-1 and SPI-2 are exposed to the host's immune system prior to/during the infection/invasion process, making them potential vaccine candidates. In this study we evaluated whether chickens vaccinated with SPI-2 T3SS components could mount a significant humoral immune response (as measured by serum IgG titres) and whether these antibodies could be transferred to progeny (as measured by egg yolk IgG titres), and whether vaccinates and progeny of vaccinates could be protected against challenge with SE. The results of our studies show that vaccinated chickens do produce high levels of SPI-2 T3SS specific serum IgG that they are able to transfer to their progeny. It was demonstrated that vaccinates and progeny of vaccinates had lower overall countable recovered Salmonella enterica subspecies enterica serovar Enteritidis (SE) per bird in most situations. 相似文献
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Emil Speidel 《Forstwissenschaftliches Centralblatt》1902,24(4):175-180
Ohne Zusammenfassung 相似文献
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Jadwiga Śliwka Marta Brylińska Emil Stefańczyk Henryka Jakuczun Iwona Wasilewicz-Flis Dorota Sołtys-Kalina Danuta Strzelczyk-Żyta Katarzyna Szajko Waldemar Marczewski 《Euphytica》2017,213(11):254
Anthocyanins occur in potato tuber skin and flesh, sprouts, leaves, stems and flowers. The goal of this study was to identify genomic regions and candidate gene alleles key for accumulation of anthocyanins in potato corolla in various quantities. QTL analyses were performed in two mapping populations segregating for flower colour intensity and candidate genes were identified on the basis of function and location (chalcone isomerase, chi; chalcone synthase, chs) or location (RNA-dependent RNA polymerase 1, RDR1). We detected three and four QTL affecting the violet flower colour intensity using the two mapping populations, respectively. In both populations a locus F, necessary for violet flower colour, segregated and we used different approaches to differentiate the qualitative effect of this locus and to detect the genetic factors affecting the quantitative flower colour intensity. The strongest QTL and the only one common for the two mapping populations was located on chromosome V. The role of all three candidate genes, chi, chs and RDR1, in control of flower colour intensity is supported to different extents by the performed genetic analyses. The most important QTL on chromosome V is most likely in the same position as the QTL for anthocyanin tuber flesh coloration described previously, which indicates that the natural variation in some biosynthetic and/or regulatory genes may influence anthocyanin levels in multiple tissues. 相似文献
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Krasnoff SB Lobkovsky EB Wach MJ Loria R Gibson DM 《Journal of agricultural and food chemistry》2005,53(24):9446-9451
The thaxtomin phytotoxins (1 and 2) from scab-producing Streptomyces pathogens of the potato are 2,5-dioxopiperazines consisting of modified l-tryptophanyl and l-phenylalanyl units. Thaxtomin A (1) is hydroxylated at C-14, the alpha carbon of the modified l-phenylalanyl moiety. Refluxing thaxtomin A in acidified MeOH, EtOH, and i-PrOH afforded C-14 thaxtomin A methyl- (3a and 3b), ethyl- (4a and 4b), and isopropyl- (5a and 5b) ethers, respectively, in both the 11S,14R (3a, 4a, and 5a) and 11S,14S (3b, 4b, and 5b) configurations. Crystal structures were determined for 3a and 4a. Extensive NMR as well as other spectroscopic data supported structural assignments for all of the derivatives. The 11S,14R-configured derivatives were slightly less potent than the natural products (1 and 2) as inhibitors of lettuce seedling root growth, whereas the activity of the 11S,14S epimers was much reduced, indicating that the configuration at C-14 found in the naturally occurring thaxtomins is essential for biological activity. Among the 11S,14R-configured compounds, potency decreased with an increasing size of the substituted alkoxy group. 相似文献
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Marta Brylińska Sylwester Sobkowiak Emil Stefańczyk Jadwiga Śliwka 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(1):33-44
Late blight is a devastating potato disease caused by Phytophthora infestans. This organism can reproduce asexually and sexually between the strains of two mating types named A1 and A2. Mating type is an important strain characteristic affecting the pathogen’s population structure. We validate different PCR markers for P. infestans mating type determination by comparison of the results obtained with the markers (W16, S1, PHYB) with the pairing test results for 26 isolates collected worldwide and for a group of 146 Polish isolates. This study identifies an interesting feature of the isolates of genotype US-1. For all these A1 mating type isolates, the product specific for A2 isolates is amplified using the marker W16. Analysis of sequences of W16 PCR products indicates high similarity of the US-1 isolates with modern A2 mating type isolates. When US-1 isolates are excluded from analysis, 95 and 96% of isolates are correctly assigned by markers W16 and S1, respectively, when compared with the pairing test results. Marker PHYB produces 14% of discrepant results with the pairing test. Our results show that molecular markers can be useful tools for P. infestans mating type determination, but their application should be preceded by validation in each local population since their efficiency may vary depending on a pathogen’s genotype. 相似文献
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Emil Cienciala Jan Tumajer Vladimír Zatloukal Jana Beranová Šárka Holá Iva Hůnová Radek Russ 《European Journal of Forest Research》2017,136(2):307-317
Decline or health deterioration of Norway spruce (Picea abies (L.) Karst.) dominated forest stands has recently been observed mainly in sub-mountainous parts of Central Europe. Forest inventory of 208 randomly distributed circular plots including field observations of spruce tree health and rot symptoms by honey fungus (Armillaria ostoyae) was used for assessing intensity of spruce forest health decline in a managed forest area of 12.7 th. ha located in Beskids Mts., NE Czech Republic. First, principal component analysis was used to separate inventory variables related to environmental stress (reduced apical increment, dry tree top and stem resin exudation due to A. ostoyae infestation) into PC1, and health deterioration symptoms associated with mechanical damage (peeling, crown breaks) into PC2. The first two principal components explained 59% of the total variability in health decline symptoms. Spatial variability of both principal components was explained using spatial lag regression model identified from a set of environmental variables including sulfur and nitrogen deposition, elevation, solar radiation, age of the forest stands and geological properties (geochemical reactivity index). Environmental stress (PC1) was associated with low elevations (sub-optimal for spruce), high level of nitrogen and sulfur deposition (their interaction), low geochemical reactivity and also stand age. On the other hand, mechanical damage (PC2) significantly increased with elevation and stand age. As the forest decline in Beskids Mts. is related to A. ostoyae spreading from local infestation hot spots, both principal components had a significant spatial autocorrelation, partly distorting the signal of environmental conditions. The results indicate that the disturbed forest soils by long-term acid deposition and subsequent nutrient degradation and more pronounced drought stress at low elevations are the most important drivers of the recent spruce health decline in Beskids Mts. 相似文献