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排序方式: 共有117条查询结果,搜索用时 46 毫秒
41.
Manuela Romagnoli Enrico Segoloni Marcello Luna Andrea Margaritelli Moreno Gatti Ulderico Santamaria Vittorio Vinciguerra 《Wood Science and Technology》2013,47(4):701-716
This study is aimed at relating the colour of Tabebuia serratifolia (Bignoniaceae family) wood to its chemical composition and technological characteristics, such as hardness and gluing, important for the manufacture of wood flooring. Samples with standard wood colour and evident chromatic anomalies were subjected to CIELAB colorimetric and gas-chromatography analyses. Red and yellow wood colour is associated with the presence of lapachol and dehydro-α-lapachone, respectively, whereas large amounts of polyphenols were found in black parts, together with other quinone compounds. Wood is hardest where lapachol gives rise to a yellow chromatic zone (L1). Delamination tests have shown that polyphenols affect lamella bonding strength. The results may be used by the wood flooring industry to identify the chemical constituents of T. serratifolia according to its colour and foresee possible problems during the production process. 相似文献
42.
Luca Ferrari Paolo Martelli Roberta Saleri Elena De Angelis Valeria Cavalli Marcello Bresaola Michele Benetti Paolo Borghetti 《Veterinary immunology and immunopathology》2013,151(3-4):193-206
The present study evaluated the lymphocyte activation in PRRSV-vaccinated pigs subsequently exposed to natural infection by in vitro stimulation of peripheral blood mononuclear cells (PBMC) with homologous vaccine and two heterologous PRRSV isolates. The responsiveness was assessed by determining IFN-γ secreting cells by ELISpot assay, lymphocyte CD8 phenotype by intracellular staining/flow cytometry, cytokine gene expression by real-time quantitative PCR and cytokine secretion by ELISA. Conventional pigs were weaned at 28 days of age and inoculated intramuscularly (IM) or needle-less intradermally (ID) with a modified-live PRRSV vaccine suspended in adjuvant, while control pigs were injected with adjuvant alone (ADJ). Blood samples were collected at vaccination, 35 days post-vaccination and after 35 days post-exposure to natural infection by a heterologous field strain. Thirty-five days post-vaccination, PRRSV vaccine induced a low but significant virus-specific IFN-γ secreting cell response upon stimulation with both the vaccine strain and the two isolates in vaccinated pigs. Conversely, after 35 days post-exposure, only the vaccine strain and the BS/114/S isolate triggered this response. Intracellular staining showed that PRRSV-specific immune cells reacting upon vaccine strain and BS/114/S stimulation were mostly CD8+ IFN-γ producing cells whereas the stimulation with BS/55 isolate induced an IFN-γ production associated to the CD8?IFN-γ+ phenotype. At 35 days post-vaccination, PBMC from vaccinated pigs showed lower IL-10 expression and release, and higher TNF-α gene expression upon stimulation with both the vaccine and viral isolates. After infection, both cytokines were not differently modulated in different groups. Immune parameters give evidence that IFN-γ secreting cells in the peripheral blood can be elicited upon PRRSV infection although vaccination itself does not stimulate high levels of these reactive cells. Moreover, the cross-reactivity against divergent PRRS viruses can show a different intensity and be differently associated with cytotoxic CD8+IFN-γ+ as well as CD8?IFN-γ+ cells. Overall, the obtained data confirmed that the immune activation against PRRSV is not dependent on the genetic divergence of the virus. Especially after infection, a different immune reactivity was evident upon stimulation with the different isolates in terms of frequency and CD8 phenotype of PRRSV-specific IFN-γ producing cells. The modulation of cytokines in vaccinated pigs appeared to be more dependent on vaccination or infection conditions than on stimulation by different isolates, and the changes of IL-10 more relevant than those of TNF-α at gene and protein levels. Moreover, under the conditions of this study, the PRRSV vaccine administered via the intradermal route by a needle-less device was confirmed to induce an immune response comparable or in some cases higher than the intramuscular route. 相似文献
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Evaluating a filtering and recirculating system to reduce dust drift in simulated sowing of dressed seed and abraded dust particle characteristics
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45.
Barbara Laddomada Miriana Durante Giacomo Mangini Leone D’Amico Marcello Salvatore Lenucci Rosanna Simeone Luciana Piarulli Giovanni Mita Antonio Blanco 《Genetic Resources and Crop Evolution》2017,64(3):587-597
Phenolic acid intake through the consumption of whole-wheat foods provides important health benefits associated with reduced risks of cardiovascular diseases and colon cancer. The genetic variation for phenolic acids was extensively studied in common wheat, but a comprehensive survey in tetraploid wheat is lacking. In this study we evaluated the genetic variability for individual and total phenolic acids concentration existing in a large collection of tetraploid wheat (Triticum turgidum L.). A 2-year evaluation was undertaken on the whole-meal flour of 111 genotypes belonging to seven T. turgidum subspecies including cultivars, landraces and wild accessions. Durum cultivars [T. turgidum subsp. durum (Desf.) MacKey], had the highest average concentration of total phenolic acids (828.7 μg g?1 dm in 2012; 834.5 μg g?1 dm in 2013) with amounts varying from 550.9 μg g?1 dm to 1701.2 μg g?1 dm, indicating a variation of greater than threefold fold. The lowest concentration of phenolic acids was found in T. turgidum subsp. dicoccum (Schrank ex Schübler) Thell. Rivet wheat (T. turgidum L. subsp. turgidum) had phenolic acid concentrations similar to those in durum, but less variation was noted among the accessions. On the other hand, the accessions of the four remaining subspecies showed lower phenolic acid concentrations and variation among the accessions as compared to durum. A total of six phenolic acids were identified across the wheat genotypes. The effects of genotype, year and year × genotype were estimated by ANOVA and resulted significant for all phenolic acids. The ratio of genotypic variance to total variance suggested the possibility of improving phenolic acid content in elite wheat germplasm through appropriate breeding programs. Moreover, significant correlations between phenolic acids and other quality characteristics of the grain were detected. 相似文献
46.
Patrizia De Gaetano Paolo Vassallo Marco Bartoli Daniele Nizzoli Andrea M. Doglioli Marcello G. Magaldi Mauro Fabiano 《Aquaculture Research》2011,42(9):1359-1370
In order to provide values of key parameters in aquaculture waste degradation modelling specifically for the Mediterranean, sampling campaigns were carried out in 2006. Accurate measurements of particulate carbon input and benthic respiration rates were performed using sediment traps and intact core incubations. The in situ measurements, compared with data from Atlantic salmon production, showed lower carbon flux and oxygen consumption, while a greater degradation capability was observed. Moreover, a temperature dependence of the benthic parameters was highlighted. Successively, the model Finite Organic Accumulation Module was used for an accurate comparison between different parameterizations. Finite Organic Accumulation Module simulates the organic carbon degradation and the net carbon accumulation on the sediment, yielding a benthic state index. In comparison with previous results, there was a decrease in benthic impacts due to minor inputs of carbon and higher mineralization rates. Moreover, a seasonal variation could be observed in the organic carbon concentration. Nevertheless, the new results remain consistent with the old ones on two points: (a) the negligible benthic impact of faeces with respect to uneaten feed and (b) the dependence of that impact on the different feed release conditions. 相似文献
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Recent plant diversity changes on Europe's mountain summits 总被引:2,自引:0,他引:2
Pauli H Gottfried M Dullinger S Abdaladze O Akhalkatsi M Benito Alonso JL Coldea G Dick J Erschbamer B Fernández Calzado R Ghosn D Holten JI Kanka R Kazakis G Kollár J Larsson P Moiseev P Moiseev D Molau U Molero Mesa J Nagy L Pelino G Puşcaş M Rossi G Stanisci A Syverhuset AO Theurillat JP Tomaselli M Unterluggauer P Villar L Vittoz P Grabherr G 《Science (New York, N.Y.)》2012,336(6079):353-355
In mountainous regions, climate warming is expected to shift species' ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe's major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras' species richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (-1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region. 相似文献
50.
Pre-harvest multiple treatments of grapevine (cv. Merlot) with the plant activator benzothiadiazole (BTH, 0.3 mM) enhanced trans-resveratrol content in berries by about 40%. An even more striking effect was observed on anthocyanin synthesis, particularly on malvidine 3-glucoside, malvidine 3-(6-O-acetyl)glucoside and malvidine 3-(6-O-p-coumaroyl)glucoside, whose amounts were more than doubled. These data were obtained with a novel and time-saving HPLC method, set up for the simultaneous detection of stilbenes and anthocyanins, using an RF-10Axl fluorimetric detector instrument, with excitation at 330 nm and emission at 374 nm, and a SPD-Avp UV detector with absorption at 520 nm. Furthermore, BTH treatments induced systemic acquired resistance in grapevine, as assessed by inoculating clusters from treated and untreated plants with Botrytis cinerea. Disease severity, estimated according to the percentage of infected berries per cluster, was significantly reduced in grapes from BTH-treated plants. These results indicate that BTH treatments, besides improving the content of two important classes of nutraceuticals, with their well-known antioxidant, antitumoral, and phytoestrogenic activities, could be exploited in vineyard to protect grape against gray mould infection, thereby limiting an excessive use of fungicides 相似文献