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181.
Seedlings of Hypericum perforatum were grown with 0.01 and 0.1 mM of chromium added to the nutrient media. A treatment with 0.01 mM Cr(VI) for seven days resulted in an increased production of protopseudohypericin (+135%), hypericin (+38%) and pseudohypericin (+5%). Treatment with 0.1 mM Cr(VI) for two days also caused an increase of protopseudohypericin (+167%), hypericin (25%) and pseudohypericin (+5%). The greatest effect of chromium treatment was observed at a concentration of 0.1 mM for seven days: protopseudohypericin increased +404% and pseudohypericin to +379%. Hypericin was not affected by this treatment.  相似文献   
182.
A survey was conducted in 16 fields cultivated with broad bean (Vicia faba L.) and garden pea (Pisum sativum L.) in nine localities of Apulia, southern Italy, to determine whether annual weeds were susceptible to the pea cyst nematode (PEACN), Heterodera goettingiana, and could therefore serve as alternate host for the nematode. The results of this study showed that black medick (Medicago lupulina L.) is a good host for the nematode increasing its population levels in the soil in the absence of the primary hosts. The identity of the PEACN was confirmed by integrative taxonomic approaches (classical, and molecular), resulting identical in all cases (broad bean and garden pea, as well as the spontaneous black medick infections). The phylogenetic analyses using ITS and coxI gene regions strongly support the identification of the populations of H. goettingiana from Italy. Also, ITS and coxI gene sequences were obtained from the same cyst, confirming the species identity in comparison to other nematodes and populations in the Goettingiana group, demonstrating that ITS and coxI gene regions of the PEACN are suitable molecular markers for accurate and unequivocal identification of the PEACN. Reproduction and histopathological analyses demonstrated a good host-suitability of black medick to the PEACN. This record enlarges the relatively narrow host-range of the pea cyst nematode and indicates the need to control M. lupulina to avoid the increase of the nematode population in the absence of the main host crop.  相似文献   
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Dehydrated lemon peel (DLP) at two levels (1.5% and 3%) was included for 30 days in the diet of gilthead seabream (Sparus aurata L.) and after 15 and 30 days the serum and skin mucus of fish were analysed. In serum, both experimental diets led to an initial decrease in glucose and lactate after which the levels became comparable to the control. Dietary DLP modulated the activity of transaminases, alanine aminotransferase and aspartate aminotransferase. The total antioxidant status showed a progressive increase in relation to levels of inclusion of DLP and time of administration (p < .05). In skin mucus, some biomolecular markers related to general stress, oxidative stress and apoptosis exhibited variations that suggest an adaptive response of fish to the new metabolic situation, resulting from the experimental diet. The inclusion of DLP in the diet seems to positively modulate the central metabolism and welfare of gilthead seabream.  相似文献   
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In the last year, a central issue in regional economic growth debate has been represented by the empirical analysis of Verdoorn's law related to the long‐term dynamic relationship between the rate of growth in output and the productivity growth due to increasing returns. Several papers have tested Verdoorn's law on European countries as well as many other world economies. Recently, attempts have been made to provide foundations for a spatial version of the original law specification. The main contributions were dedicated to the inclusion of spatial dependence in the economic model. Surprisingly, in the literature on Verdoom's law the analysis of the spatial heterogeneity is not often considered. The aim of this paper is the regional analysis of the spatial dependence and heterogeneity in Verdoorn's law, identifying spatial regimes that can be interpreted as clusters of productivity growth in European regions at NUTS 2 level. To pursue this objective, an optimization algorithm for the identification of groups is used. This constitutes a modified version of Simulated Annealing.  相似文献   
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