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241.
The concentrations of 13 trace elements were determined in soils and Sangiovese grapes collected in vineyard zones of Tuscany (Italy). The purpose was to establish a correspondence among the chemical composition of grape, the geochemistry of vineyard soil and the geolithological features of cultivation zone, and determine the provenance of the grapes by means of their chemical fingerprints. Statistical analysis of Ba, Rb and Sr concentrations distinguished three classes of grapes according to the geochemical and geopedological characteristics of the soils. Grapes with the highest Sr levels grew on high‐Sr soils derived from calcareous, calcareous‐marly and marly‐clayey rocks, whereas the most elevated Rb concentrations characterized the berries cultivated on soils formed from clayey‐marly and sandy‐marly lithologies. Grapes with the highest Ba concentrations grew on soil derived from arenaceous rocks and carbonate lithologies of evaporitic origin. These findings suggested that Ba, Rb and Sr could be used as fingerprints for the chemical traceability of Sangiovese grapes. 相似文献
242.
Giovanni Di Matteo Luigi Perini Paolo Atzori Paolo De Angelis Tiziano Mei Giada Bertini Gianfranco Fabbio Giuseppe Scarascia Mugnozza 《林业研究》2014,25(4):839-845
We estimated water-use efficiency and potential photosynthetic assimilation of Holm oak(Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in two Mediterranean coppice forests. We used standard techniques for quantifying gas exchange and carbon isotopes in leaves and analyzed total chlorophyll, carotenoids and nitrogen in leaves collected from Mediterranean forests managed under the coppice system. We postulated that responses to drought of coppiced trees would lead to differential responses in physiological traits and that these traits could be used by foresters to adapt to predicted warming and drying in the Mediterranean area. We observed physiological responses of the coppiced trees that suggested acclimation in photosynthetic potential and water-use efficiency:(1) a significant reduction in stomatal conductance(p0.01) wasrecorded as the drought increased at the SW site;(2) foliar δ13C increased as drought increased at the SW site(p0.01);(3) variations in levels of carotenoids and foliar nitrogen, and differences in foliar morphology were recorded, and were tentatively attributed to variation in photosynthetic assimilation between sites. These findings increase knowledge of the capacity for acclimation of managed forests in the Mediterranean region of Europe. 相似文献
243.
244.
Mario Giorgi Sara Del Carlo Micaela Sgorbini Giuseppe Saccomanni 《Journal of Equine Veterinary Science》2009
Tramadol (T) is a centrally acting analgesic structurally related to codeine and morphine. Recently, T has been reported to be metabolized faster to inactive metabolites in goats, dogs, and horses than in cats. Clinical effectiveness of T has been questioned in species that mainly metabolize this molecule to inactive metabolites, suggesting that this drug could be not suitable as effective and safe treatment for pain as in humans. The purpose of the study is to determine the pharmacokinetics of T and its main metabolites in donkeys to evaluate its prospective use in clinical practice. The subjects were 12 male donkeys, 6 to 9 years old and weighing 300 to 380 kg. Each subject received a single dose of 2.5 mg/kg T either orally or intravenously. Plasma T, O-desmethyltramadol (M1), N-desmethyltramadol (M2), and N-,O-didesmethyltramadol (M5) concentrations were evaluated by high-pressure liquid chromatography (HPLC). Pharmacokinetic parameters in both administrations were calculated according to a non-compartmental model. After intravenous administration, T was detectable up to 10 hours, whereas M1, M2, and M5 were detectable from 15 minutes up to 6 hours. The total amount of M2 was greater than M1, which was greater than M5. The T area under the concentration/time curve (AUC), T1/2 λz (terminal half-life), and Cl/F (Clearance/F where F is the fraction of the drug absorbed) were 14,522 ± 2,554 h/ng/mL, 1.55 ± 0.74 hours, and 167 ± 22.3 mL/h/kg, respectively. After oral administration, T was detectable up to 8 hours to a lower extent than after the intravenous route. The total amount of M2 was greater than M5, which was greater than M1. The T AUC, T1/2 λz, and Cl/F were 4,624 ± 2,002 h/ng/mL, 4.22 ± 2.32 hours, and 495 ± 170 mL/h/kg, respectively. The bioavailability of the oral formulation was 11.7 ± 5.1%. In conclusion, despite the effectiveness of intravenous administration of T, oral administration did not reach the minimum plasma concentration of both M1 and parental drug reported in humans as needed to achieve analgesia in donkeys. 相似文献
245.
G. Marino A. Zanghi M. Quartuccio S. Cristarella M. Giuseppe G. Catone 《Journal of Equine Veterinary Science》2009,29(10):728-733
Nematodes of the genuses Strongylus and Setaria are able to erratically migrate to the equine testis and provoke characteristic inflammatory changes. Moreover, the presence of living parasites in scrotal testes is a scarce finding in which only the tracts and related lesions may be observed. In a 20-year experience of equine testes observed in abattoirs, 13 cases of atypical inflammatory lesions in scrotal testes were collected. On opening of the vaginal cavity, hydrocele was consistantly observed, and the Morgagni's appendix was enlarged, prominent, and reddish. Large, elongated, or irregular prominent red to yellow areas were visible on the testicular or epididymal serosa. Edematous enlargement of the epididymal head or tail was occasionally observed. In two cases, the described lesions were detected together with nematodes of the species Setaria equina, free and viable or encapsulated in the visceral and parietal layers of the tunica vaginalis, confirming the hypothesized cause. Histologically, the serosal lesions were interpreted as parasitic tracts, characterized by hemorrhage and leukocyte infiltrates in recent lesions or by granulation tissue with numerous macrophages in elderly ones. In the latter, areas of squamous metaplasia could be observed in the appendix testis and in the epididymal duct. Associated microscopic lesions included diffuse periorchitis, lymphocytic interstitial orchitis with mild to severe degeneration of seminiferous tubules, and vasculitis, epididymitis, and sperm granuloma. 相似文献
246.
This study describes the aluminum (Al) accumulation in relation to macronutrient and micronutrient elements in 19 Melastomataceae species in the Guayana Region in Venezuela. The purpose was to investigate the Al accumulation in four tribes and different life forms. Aluminum accumulation was predicted in the basal tribes Miconieae and Merianieae in contrast to the derived tribes and herbs from any tribe, which generally do not accumulate Al. The survey was done in a vegetation continuum, which includes a savanna shrubland, a palm‐swamp community, and an evergreen forest in the Guayana region in southeastern Venezuela. The highest value of soil Al concentration was found in the savanna shrubland, where ten lignified Miconiae and one Merianeae Al accumulators were present. At the forest, the site with highest soil acidity, four Al‐accumulator tree species from Miconiae were found. Miconia lepidota showed similar Al foliar concentrations in the savanna shrubland and forest, but foliar Ca was lower in the forest, even though it was the site with highest Ca in the soil. At the palm‐swamp community, the Melastomeae shrub Macairea pachyphylla was found with an Al concentration of 0.59 g kg–1 in leaves and 0.16 g kg–1 in bark. At the same site, Al accumulation occurred in one Microlicieae species, one Miconieae species, and in the Melastomeae herbs Pterogastra divaricata (13.25 g [kg dry mass]–1) and Pterolepis trichotoma (17.83 g kg–1). The report of Al hyperaccumulation in P. trichotoma is new for the genus, and Al accumulation in herbs is considered exceptional. The foliar Al concentration was positively correlated (p < 0.005) with Fe (r = 0.64, n = 20) and Zn (r = 0.63). The analysis of the relationships between soil Al, Fe, or Zn and the concentrations of these elements in leaves revealed they were not significantly correlated. The results indicate Al hyperaccumulation in two herbaceous Melastoamataceae species and suggest Al accumulation in this life form deserves future research. However, they also confirm the highest number of Al accumulators in lignified species of the ancient tribe Miconiae (14 out of 19 species studied). 相似文献
247.
Luigi Badalucco Maria Rao Claudio Colombo Giuseppe Palumbo Vito Armando Laudicina Liliana Gianfreda 《Biology and Fertility of Soils》2010,46(5):481-489
Intensive agriculture (IA) is widespread in South Italy, although it requires frequent tillage, large amounts of fertilizers
and irrigation water. We have assessed the efficacy of reversing IA to sustainable agriculture (SA) in recovering quality
of a typical South Italy soil (Lithic Haploxeralf). This reversion, lasting from 2000 to 2007, replaced 75% of nutrients formerly
supplied inorganically by farmyard manuring and reduced the tillage frequency. Several chemical and biochemical properties,
functionally related to C and N mineralisation–immobilisation processes and to P and S nutrient cycles, were monitored annually
from 2005 to 2007 in the spring. Reversing IA to SA decreased soil bulk density, almost doubled the soil organic matter (SOM)
as favoured the immobilisation of C and N, increased most soil microbial indicators but decreased contents of nitrate, mineral
N and K2SO4-extractable C. The K2SO4-extractable C/K2SO4-extractable organic N ratio suggested that substrate quality rather than the mass of readily available C and N affected biomass
and activity of soil microflora. Also, the largely higher 10-day-evolved CO2–C-to-inorganic N ratio under SA than IA indicated that higher C mineralisation, associated with higher microbial biomass
N immobilisation, occurred under SA than IA. Decreases in most soil enzyme activities under IA, compared to SA, were much
higher than concomitant decreases in SOM content. Soil salinity and sodicity were always higher in IA than SA soil, although
not critically high, likely due to the intensive inorganic fertilisation as irrigation waters were qualitatively and quantitatively
the same between the two soils. Thus, we suggest that the cumulative small but long-term saline (osmotic) and sodic (dispersing)
effects in IA soil decreased the microbial variables more than total organic C and increased soil bulk density. 相似文献
248.
Greco G Colarieti ML Toscano G Iamarino G Rao MA Gianfreda L 《Journal of agricultural and food chemistry》2006,54(18):6776-6782
The toxicity of olive mill wastewaters (OMW) is commonly attributed to monomeric phenols. OMW were treated in an aerated, stirred reactor containing agricultural soil, where the oxidative polymerization of phenols took place. In 24 h, OMW monomeric phenols decreased by >90%. This resulted in a corresponding reduction in phytotoxicity, as measured by germination tests with tomato and English cress seeds, and in microbial toxicity, as measured by lag phase duration in Bacillus cereus batch growth. Soil germination capability after irrigation with OMW was assessed in long-term pot experiments. The relative germination percentage of tomato was higher when the soil was irrigated with treated OMW rather than with untreated ones, although it was lower than the control (e.g., soil irrigated with distilled water). At longer incubation times, a complete recovery of the soil germination capability was achieved with treated, but not with untreated, OMW. 相似文献
249.
Forlani G Obojska A Berlicki Ł Kafarski P 《Journal of agricultural and food chemistry》2006,54(3):796-802
A series of phosphinothricin derivatives with a modified methyl group, designed on the basis of the crystal structure of the complex formed by the inhibitor and the target enzyme from Salmonella typhimurium, were evaluated as potential inhibitors of plant glutamine synthetase. These compounds were previously shown to be equipotent or slightly weaker inhibitors to the lead compound against the bacterial enzyme. Because of the presence in higher plants of at least two enzyme forms with different subcellular localization and possible separate metabolic functions, plastidial and cytosolic glutamine synthetases were purified to electrophoretic homogeneity from spinach chloroplasts and cultured tobacco cells, respectively. Kinetic analysis confirmed the ability of the phosphinothricin analogues to inhibit both isoenzymes in the micromolar range, with a mechanism of a competitive type with respect to glutamate. Interestingly, some of them exerted a differential effect against either the two plant isoforms, or against the plant versus the bacterial enzyme. 相似文献
250.
介绍了意大利的甜瓜栽培方式,并对中国甜瓜品种与意大利甜瓜品种的综合性状进行了比较,试种结果表明,中蜜1号等7个中国甜瓜品种适应意大利的甜瓜栽培方式,在意大利表现出良好的性状。 相似文献