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51.
The effect of three different nitrogen (N) supply forms differing in their ammonium-to-nitrate (NH(4):NO(3)) ratio (100% NH(4), 50% NH(4) + 50% NO(3), 100% NO(3)) under three different levels of daily photosynthetic active radiation (PAR) (low, 5.0; medium, 6.8; high, 9.0 mol m(-2) day(-1)) on a range of desirable health-promoting phytochemicals in Brassica rapa subsp. nipposinica var. chinoleifera and Brassica juncea was determined. The 100% NH(4) supply under medium PAR levels led to the highest concentration of glucosinolates based on a low nitrogen/sulfur ratio as well as high levels of carotenoids in the leaves of both Brassica species. However, the 100% NH(4) supply under low and medium PAR levels resulted in low concentrations of flavonoids based on high N concentration in the leaves. Thus, the data provided here have strong implications for crop management strategies aimed at optimizing both the concentration and composition of a range of phytochemicals.  相似文献   
52.
In this article, we propose a spatial model for analyzing extreme rainfall values over the Triveneto region (Italy). We assess the existence of a long-term trend in the extremes. To integrate data coming from the different stations, we propose a hierarchical model. At the first level, for each monitoring station we model data by making use of a generalized extreme value distribution; at the second level, we combine results from the first stage by exploiting recent advances in modeling nonstationary spatial random fields.  相似文献   
53.
Journal of Soils and Sediments - Humic acids (HA) have several environmental roles, but are particularly important in aquatic environments, being recognized as redox active natural organic matter...  相似文献   
54.
Polyphenols are widespread in vegetables and fruits. They can play an important role in human diet and health, and they influence the sensorial properties of many foods, and act as natural antioxidants. This study was conducted using HPLC/DAD, tyrosinase biosensor, and differential pulse voltammetry (DPV) analyses to detect polyphenolic compounds in natural complex matrices. The analyses were applied to a series of both standards and natural extracts derived from grape, olives, and green tea. The pure compounds include phenolic acids, flavones, flavonols, catechins, tannins, and oleuropein. HPLC/DAD, DPV, and the biosensor approach were used as independent analytical techniques. Bare graphite screen-printed electrodes were employed in DPV and in the biosensor analysis. The most accurate data were obtained by HPLC/DAD analysis, while the DPV approach using screen-printed electrodes could represent a quick screening method for the determination of polyphenols in natural extracts. Use of the biosensor for the analysis of complex matrices needs further study in order to improve its performance.  相似文献   
55.
Feijoa sellowiana Berg. fruits and especially the acetonic extract have been shown to possess biological activities, although the responsible compounds have never been identified. The present study was designed to evaluate the anti-inflammatory activity of an acetonic extract from F. sellowiana Berg. fruits on the nitric oxide (NO) pathway, which plays an important role in inflammation. To this aim the J774 cell line, which expresses inducible nitric oxide synthase (iNOS) following stimulation with lipopolysaccharide (LPS), has been utilized, and the effects of this extract and its fractions on NO production, iNOS protein expression, and signal pathways involved in its regulation have been evaluated. This study demonstrates that at least some part of the anti-inflammatory activity of the acetonic extract is due to the suppression of NO production by flavone and stearic acid. The mechanism of this inhibition seems to be related to an action on the expression of the enzyme iNOS through the attenuation of nuclear factor kappaB (NF-kappaB) and/or mitogen-activated protein kinase (MAPK) activation.  相似文献   
56.
Four different polyphenolic compounds were isolated by chromatographic methods from methanolic and hydromethanolic extracts of Ipomoea batatas tuber flour. On the basis of UV, mass, and NMR analysis procedures, the structure of the isolated compounds were determined as 4,5-di-O-caffeoyldaucic acid (1), 4-O-caffeoylquinic acid (2), 3,5-di-O-caffeoylquinic acid (3), and 1,3-di-O-caffeoylquinic acid (4). To the best of our knowledge, this is the first report of isolation and characterization of compound 1. Then, we evaluated the antioxidant activity of daucic acid derivative by using DPPH and FRAP methods together with authentic antioxidant standards, l-ascorbic acid, tert-butyl-4-hydroxy toluene (BHT), and gallic acid. The activity of compound 1 in both methods was higher than that of all standards used at the same molar concentration.  相似文献   
57.
Plasma cortisol is the most commonly used indicator of stress in fish but, as the blood sampling procedure itself can be a source of stress, it would be helpful to measure cortisol using less invasive matrices. It is also necessary to find alternative matrices as stress indicators in dead fish in which blood sampling is impossible. In the present study, we investigated transport stress in three aquaculture species, European sea bass (Dicentrarchus labrax L.), common carp (Cyprinus carpio L.) and rainbow trout (Oncorhynchus mykiss Walbaum), by cortisol determination (radioimmunoassay) in plasma and other matrices (skin mucus, gut content, lateral muscle and caudal fin). Cortisol significantly increased after transport in all species and matrices, except in the sea bass gut content, where it remained unchanged. The three species responded to transport stress by producing different cortisol levels. In conclusion, the significant correlation found between plasma cortisol and most of the other matrices opens up the possibility of using them to evaluate stress in fish: mucus sampling is a less invasive method than blood sampling, and in addition to muscle and fin sampling, it can be used in postmortem fish.  相似文献   
58.
In potato breeding and selection, storability should be regarded as equally important as yield, disease resistance, and quality. A study documenting the dormancy period, sprouting behavior, and weight loss of 17 International Potato Center potato elite and advanced clones was carried out in Tashkent, Uzbekistan, under cellar and cold store conditions, during 2008 and 2009. Ninety tubers of each of 17 clones were allocated to experimental units of 30 tubers each placed in trays and randomized in three replications following a random complete block design. Therefore, there were three replications of 30 seed tubers each per entry. The dormancy period ranged from 77 to 115 days and from 100 to 186 days under cellar and cold storage, respectively. There was a relatively high positive correlation (0.69) for dormancy period between storage systems, indicating that clones demonstrating longer and shorter dormancy periods under one system will also behave similarly under the other system. A negative correlation (−0.53 and −0.88) was found between dormancy period and length of the longest sprout in cellar and cold store, respectively, meaning that clones with shorter dormancy often showed a greater length of their longest sprout. The weight loss percentage per tuber was similar in both storage systems, from 5.0% to 8.0% in the cellar and from 5.0% to 9.8% in the cold store, although for different storage periods (an average of 110 and 166 days under cellar and cold storage conditions, respectively). The study indicated that under cellar conditions, clones with a longer dormancy period and slower rate of sprout growth have less weight loss during storage and therefore better keeping quality.  相似文献   
59.
Growth, weight at birth and daily weight gain (DWG) on 12 water buffalo calves, starting from 6 days of age until completion of weaning, was investigated in this study. Different feeding regimens were given to two groups of animals with regard to daily milk replacer: (1) group 1 (G1) received a double concentration in single administration; whereas (2) group 2 (G2) received the same amount of milk replacer split twice daily. Blood samples were collected from each calf on days 6, 30, 60 and 90 to evaluate acute phase proteins (haptoglobin), bactericide activity, lysozime, total protein content and biochemical parameters. No differences were observed between the two groups in terms of dry matter intake, feed efficiency and live body weight at the end of the study. Interestingly, a significantly (P?<?0.05) reduced DWG was observed earlier in G1 (day 45) than in G2 (day 60). Gastrointestinal disorders were not recorded throughout the experimental period, and no significant differences were recorded between the two groups for all considered parameters. This study confirms the possibility of utilising one daily administration of milk replacer in water buffalo calf during weaning. This new approach facilitates calves management, without interfering with calves growing performances.  相似文献   
60.
OBJECTIVE: To determine the efficacy of triamcinolone acetonide topical solution (TTS) in dogs for use in reduction of clinical signs of pruritic inflammatory skin diseases of a known or suspected allergic basis and to evaluate adverse effects associated with TTS administration. ANIMALS: 103 pruritic adult dogs with known or suspected allergic skin disease. PROCEDURE: Dogs were treated for 4 weeks with TTS or with vehicle solution (control dogs) in a multiple-center study. Clinical signs were scored by owners and by examining veterinarians before and after treatment. Blood samples obtained before and after treatment were subjected to routine hematologic and serum biochemical analyses. RESULTS: Treatment success, as defined by an improvement of at least 2 of 6 grades in overall clinical score, was evident in 35 of 52 (67%) TTS-treated dogs (mean improvement, 1.98) and 12 of 51 (24%) control dogs (mean improvement, 0.29). For several criteria, TTS was significantly more effective than vehicle in reducing clinical signs. Minor alterations in hematologic determinations in TTS-treated dogs were limited to slightly lower total leukocyte, lymphocyte, and eosinophil counts after treatment. Minor adverse effects were reported by owners in 6 of 52 (12%) TTS-treated and 9 of 51 (18%) control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Triamcinolone used as a spray solution at a concentration approximately one-sixth the concentration of triamcinolone topical preparations currently available for veterinary use is effective for short-term alleviation of allergic pruritus in dogs. Adverse effects are few and mild and, thus, do not preclude prolonged treatment with the solution.  相似文献   
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