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261.
One of the main olive oil phenolic compounds, hydroxytyrosol (3,4-DHPEA), exerts in vitro chemopreventive activities (antiproliferative and pro-apoptotic) on tumor cells through the accumulation of H(2)O(2) in the culture medium. However, the phenol composition of virgin olive oil is complex, and 3,4-DHPEA is present at low concentrations when compared to other secoiridoids. In this study, the in vitro chemopreventive activities of complex virgin olive oil phenolic extracts (VOO-PE, derived from the four Italian cultivars Nocellara del Belice, Coratina, Ogliarola, and Taggiasca) were compared to each other and related to the amount of the single phenolic constituents. A great chemopreventive potential among the different VOO-PE was found following this order: Ogliarola > Coratina > Nocellara > Taggiasca. The antiproliferative and pro-apoptotic activities of VOO-PE were positively correlated to the secoiridoid content and negatively correlated to the concentration of both phenyl alcohols and lignans. All extracts induced H(2)O(2) accumulation in the culture medium, but this phenomenon was not responsible for their pro-apoptotic activity. When tested in a complex mixture, the olive oil phenols exerted a more potent chemopreventive effect compared to the isolated compounds, and this effect could be due either to a synergistic action of components or to any other unidentified extract constituent.  相似文献   
262.
263.
Tropical Animal Health and Production - This study aimed to estimate the genetic parameters of milk (305-day milk yield (MY305)), growth (weaning weight (WW), yearling weight (YW), and weight at...  相似文献   
264.
House geckos in the genus Hemidactylus are highly successful colonizers of regions beyond their native range, with colonization often resulting in displacement of native gecko species through competitive interactions for daytime refuge (crevices) and prey resources. We report on data collected from nighttime surveys undertaken in April–May 2014 on Barbados, West Indies, that focused on the distribution and abundance of the endemic Barbados leaf‐toed gecko (Phyllodactylus pulcher) and the introduced tropical house gecko (Hemidactylus mabouia) along unlit coastal walls and among boulders in the grounds of a hotel resort. In contrast to patterns of displacement of native species by H. mabouia seen elsewhere, P. pulcher was more abundant than H. mabouia on coastal walls, whereas the latter was found in greater numbers using boulders at this site. Walls and boulders differed with regard to availability of diurnal refugia suitable for geckos, with the walls having high frequency of small crevices with openings <20 mm, and boulders offering very little cover other than the underside of the boulder itself. To investigate whether this niche separation was a result of differences in diurnal refuge use between the species, we conducted experimental trials in which geckos were allowed to select between refugia with different characteristics. Both species selected for narrower and warmer refugia, and refugia that had been previously occupied by the other species. These shared preferences for refugia type suggest that other factors underlie the niche separation observed in the field. In supporting high densities of P. pulcher, coastal walls could offer important secondary habitat by augmenting the natural cliff side habitat of this endemic gecko, a finding that could be exploited for the conservation of this candidate species for Critically Endangered classification.  相似文献   
265.
ABSTRACT Fusarium wilt of lettuce, caused worldwide by Fusarium oxysporum f. sp. lactucae, is an emerging seed-transmitted disease on Lactuca sativa. In order to develop a molecular diagnostic tool for identifying race 1 (VCG0300) of the pathogen on vegetable samples, an effective technique is presented. Inter-retrotransposon amplified polymorphism polymerase chain reaction (PCR), a technique based on the amplification of genomic regions between long terminal repeats, was applied. It was shown to be useful for grouping F. oxysporum f. sp. lactucae race 1 isolates. Inter-retrotransposon sequence-characterized amplified regions (IR-SCAR) was used to develop a specific set of PCR primers to be utilized for differentiating F. oxysporum f. sp. lactucae isolates from other F. oxysporum isolates. The specific primers were able to uniquely amplify fungal genomic DNA from race 1 isolates obtained in Italy, Portugal, the United States, Japan, and Taiwan. The primers also were specific to pathogen DNA obtained from artificially infected lettuce seed and naturally and artificially infected plants.  相似文献   
266.
Calcite and gypsum are salts of major ions characterized by poor solubility compared with other salts that may precipitate in soils. Knowledge of calcite and gypsum solubility products in water‐saturated soil samples substantially contributes to a better assessment of processes involved in soil salinity. The new SALSOLCHEMIS code for chemical equilibrium assessment was parameterized with published analytical data for aqueous synthetic calcite and gypsum‐saturated solutions. Once parameterized, SALSOLCHEMIS was applied to calculations of the ionic activity products of calcium carbonate and calcium sulphate in 133 water‐saturated soil samples from an irrigated salt‐affected agricultural area in a semi‐arid Mediterranean climate. During parameterization, sufficiently constant values for the ionic activity products of calcium carbonate and calcium sulphate were obtained only when the following were used in SALSOLCHEMIS: (i) the equations of Sposito & Traina for the free ion activity coefficient calculation, (ii) the assumption of the non‐existence of the Ca (HCO 3)+ and CaCO3o ion pairs and (iii) a paradigm of total ion activity coefficients. The value of 4.62 can be assumed to be a reliable gypsum solubility product (pKs) in simple aqueous and soil solutions, while a value of 8.43 can only be assumed as a reliable calcite solubility product (pKs) in simple aqueous solutions. The saturated pastes and saturation extracts were found to be calcite over‐saturated, with the former significantly being less so (p IAP = 8.29) than the latter (p IAP = 8.22). The calcite over‐saturation of saturated pastes increased with the soil organic matter content. Nevertheless, the inhibition of calcite precipitation is caused by the soluble organic matter from a dissolved organic carbon threshold value that lies between 7 and 12 mm . The hypothesis of thermodynamic equilibrium is more adequate for the saturated pastes than for the saturation extracts.  相似文献   
267.

Purpose  

The aim of this study was to evaluate polychlorinated biphenyl (PCB) removal in relation to the associated bacterial community composition in Ohio River sediments (USA) using field and laboratory approaches.  相似文献   
268.
The activity of different types of natural compounds and of two biofungicides based on Bacillus subtilis and Ampelomyces quisqualis alone and in combination with fungicides was tested against powdery mildew of zucchini. The efficacy was compared to the activity of fungicides used alone in four experimental trials carried out in the open field and under greenhouse conditions. The Podosphaera xanthii population used throughout the work was partially resistant to azoxystrobin, whereas it was susceptible to mychlobutanil. Sulphur plus terpenes and mustard oil consistently controlled powdery mildew, followed by mychlobutanil alone or in combination with A. quisqualis. B. subtilis and A. quisqualis when tested alone were partially effective. The combination of azoxystrobin and B. subtilis only delayed the spread of the pathogen.  相似文献   
269.
Tritrichomonas foetus is an extracellular parasite of the reproductive tract in cattle. The mechanism by which T. foetus causes abortion in cattle is largely unknown. There are no studies of infection in the cow oviducts, almost all published papers are related to vagina infection and few articles focusing on the uterus. The aim of the present study was to establish a working model of bovine oviduct epithelial cells and submit these cells to Tritrichomonas foetus interaction. Twenty bovine oviducts were obtained from cows at a commercial abattoir and T. foetus was injected through the isthmus into the oviduct lumen. The whole oviduct was analyzed by scanning and transmission electron microscopy. The results reported here demonstrate that: (1) fresh whole oviducts can be used as a good model to study parasite-host cell interaction; (2) cow oviduct epithelium has been shown to consist of two cell types: ciliated and nonciliated secretory cells, and T. foetus displayed great specificity for the nonciliated cells localized in the deeper oviduct folds; (3) T. foetus adheres as single separate cells, and maintains the flagella externalized; (4) differently from T. vaginalis, T. foetus does not change its shape during the adhesion process; and (5) oviduct cells exhibited morphological characteristics of apoptosis after trichomonadal interaction.  相似文献   
270.
Two representative Italian emmer wheat (Triticum dicoccum) landraces, two selected lines and three improved emmer wheat cultivars, derived from crosses with durum wheat (Molisano landrace × ‘Simeto’), were tested for their susceptibility to Tilletia indica, the cause of Karnal bunt of wheat. Plants of emmer wheat were inoculated by injecting allantoid sporidial suspensions into the boot cavity of plants, just prior to ear emergence. A highly susceptible Indian spring wheat cultivar (Triticum aestivum) was used as a comparative control. At maturity of the plants, the seeds were harvested and assessed for incidence and severity of disease. All emmer wheat genotypes tested were infected but showed differing levels of susceptibility. The percentage of infected seeds for individual genotypes ranged from 5.4 to 75.0% compared with 99.1% for WL-711. The severity of infection was less in the old landraces, but it was higher in all the improved emmer wheat cultivars. In conclusion, Italian cultivars of emmer wheat were found to be highly susceptible to T. indica, and are potentially able to support the establishment of the pathogen.Authors L. Riccioni and M. Valvassori contributed equally to this work and should both be considered as first author.  相似文献   
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