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101.
Mariangela Marrelli Monica Rosa Loizzo Marcello Nicoletti Francesco Menichini Filomena Conforti 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):340-346
One of the most important strategy in the treatment of obesity includes the development of nutrient digestion and absorption inhibitors. Inhibition of digestive enzymes is one of the most widely studied mechanisms used to determine the potential efficacy of natural products as hypolipidemic and hypoglycaemic agents. In vitro studies here reported were performed to evaluate the inhibitory activity of five species (as hydroalcoholic extracts) of edible plants from Calabria region (Italy) on amylase and lipase by monitoring the hydrolysis of p-NPC and the hydrolysis of glycoside bonds in digestible carbohydrate foods. The formulation obtained from Clematis vitalba L. exhibited the strongest inhibitory effect on pancreatic lipase (IC50?=?0.99 mg/ml) and on α-amylase (IC50?=?31.52 μg/ml). In order to explore metabolome production HPTLC analysis of the extracts was performed, revealing the predominance of (±)-catechin, caffeic acid and chlorogenic acid in C. vitalba formulation at concentration of 23.18?±?3.14, 13.63?±?0.65 and 18.88?±?0.76 mg/g, respectively. GC/MS analysis was used to identify fatty acids and terpene composition. 相似文献
102.
Roberto Confalonieri Alessia Perego Marcello Ermido Chiodini Barbara Scaglia Alexandra Stella Rosenmund Marco Acutis 《Field Crops Research》2009
Pre-samplings for sample size determination are strongly recommended to assure the reliability of collected data. However, there is a certain dearth of references about sample size determination in field experiments. Seldom if ever, differences in sample size were identified under different management conditions, plant traits, varieties grown and crop age. In order to analyze any differences in sample size for some of the variables measurable in rice field experiments, the visual jackknife method was applied to pre-samples collected in a paddy rice field in Northern Italy, where a management typical for European rice was conducted. Sample sizes for 14 variables describing plant features (plant density, spikelet sterility, biomass, carbon and nitrogen concentration for the different plant organs and for the whole plant) and for 12 variables describing physical and chemical soil features (texture, pH, water holding capacity, soil organic matter, total carbon and nitrogen concentration, mineral nitrogen concentration) and soil microbial activity were estimated. The elementary units of observation were a 3-plant sample and an aggregate sample of four 125 cm3 sub-samples respectively for plant- and soil-related variables. Sample sizes ranged between 15 and 27 for plant-related variables and between 5 and 6 for soil variables. Relating to plant features, remarkable differences in sample size were observed in carbon concentration values of different plant organs, probably due to maintenance respiration. Homogeneity among sample sizes for soil variables could be explained by the capability of aggregate samples in capturing a big part of the total variance. This study underlines importance of carrying out pre-samplings aiming at sample size determination for different variables describing the cropping system. 相似文献
103.
A total of 1,366 Rhynchosporium secalis isolates causing scald on barley, rye, and wild barley (Hordeum spontaneum) were assayed for restriction fragment length polymorphism loci, DNA fingerprints, and mating type, to characterize global genetic structure. The isolates originated from 31 field populations on five continents. Hierarchical analysis revealed that more than 70% of the total genetic variation within regions was distributed within a barley field. At the global level, only 58% of the total genetic variation was distributed within fields, while 11% was distributed among fields within regions, and 31% was distributed among regions. A significant correlation was found between genetic and geographic distance. These findings suggest that gene flow is common at the local level while it is low between regions on the same continent, and rare between continents. Analyses of multilocus associations, genotype diversity, and mating type frequencies indicate that sexual recombination is occurring in most of the populations. We found the highest allele richness in Scandinavia followed by Switzerland. This suggests that R. secalis may not have originated at the center of origin of barley, the Fertile Crescent, nor in a secondary center of diversity of barley, Ethiopia. 相似文献
104.
Priscilla Bettini Rita Baraldi Francesca Rapparini Lorenzo Melani Maria Luisa Mauro Daniela Bindi Marcello Buiatti 《Scientia Horticulturae》2010
In the present paper we report on the effects of the insertion of the Agrobacterium rhizogenes rolC gene in the tomato (Solanum lycopersicum L., formerly Lycopersicon esculentum Mill.) cultivar Tondino. Several transgenic lines were successfully obtained, between which two clones, rolC1 and rolC3, were chosen for the analysis of morpho-productive traits as well as of the endogenous levels of auxin and abscisic acid. Consistent with the known phenotypic effect of this gene, the transformed tomato plants were significantly shorter than the corresponding controls. On the other hand, even if yield was not affected by the transformation in terms of average number of fruits produced, fruit weight was significantly lower in the transgenics with respect to the controls. Therefore, insertion of the rolC gene does not lead to an improvement in plant productivity. 相似文献
105.
106.
Gianluigi Mazzoccoli Angelo De Cata Antonio Greco Marcello Damato Nunzia Marzulli Mariangela Pia Dagostino Stefano Carughi Federico Perfetto Roberto Tarquini 《Journal of circadian rhythms》2010,8(1):6
Background
Immunosenescence is a process that affects all cell compartments of the immune system and the contribution of the immune system to healthy aging and longevity is still an open question. Lymphocyte subpopulations present different patterns of circadian variation and in the elderly alteration of circadian rhythmicity has been evidenced. The aim of our study was to analyze the dynamics of variation of specific cytotoxic lymphocyte subsets in old aged subjects. 相似文献107.
Marcello Donatelli Gianni Bellocchi Ephrem Habyarimana Roberto Confalonieri Fabio Micale 《Computers and Electronics in Agriculture》2009,69(2):165-170
Wind is a library providing a collection of stochastic approaches to generate wind speed data on daily and hourly time steps. Daily generation refers to as mean, maximum and minimum daily wind speed. The library is made available as software component, inclusive of hypertext help file, allowing the development of language-independent clients under Windows operating systems. The component includes advanced features for re-use in custom developed applications, and it allows independent extensions by third parties without requiring its re-compilation. Illustrative examples on how to extend and re-use the library are provided as C# code projects. 相似文献
108.
Ariadne Missono Brondi Josiane Souza Pereira Daniel Vitor Xavier Monteiro de Castro Jerusa Simone Garcia Marcello Garcia Trevisan 《Communications in Soil Science and Plant Analysis》2016,47(22):2506-2513
Humic substances are the main responsible for soil conditioning and are one of the major components of the composting product. However, there is still little information about their composition and mechanisms of activity. This study aimed to evaluate quantitatively the humic and fulvic fraction by size-exclusion liquid chromatography and the metal content by atomic absorption spectrometry. The chromatographic method used was efficient for humic and fulvic acids quantitation. Levels of 1.73 ± 0.03 and 1.6 ± 0.5 g kg?1 were found for chicken manure regarding humic and fulvic acids, respectively, and 5.1 ± 0.9 and 1.2 ± 0.1 g kg?1 for peat. The metal contents indicated the need of a mineral enrichment, because only the levels of iron reached the minimum recommended by legislation. It was also observed that evaluated organic fertilizers were in accordance with the specifications established by legislation in relation to carbon and total nitrogen and the pathogen levels. 相似文献
109.
Virgilio Balmas Barbara Scherm Pietro Di Primo Domenico Rau Angela Marcello Quirico Migheli 《European journal of plant pathology / European Foundation for Plant Pathology》2005,111(1):1-8
Random amplification of polymorphic DNA (RAPD-PCR) analysis was conducted on 48 isolates of Fusarium oxysporum f. sp. radicis-lycopersici (F.o.r.l.) from different geographic regions, representing all known vegetative compatibility groups (VCGs) except VCG 0097 and VCG 0099 and on eight isolates of F.oxysporum f. sp. lycopersici (F.o.l.), representing VCGs 0030, 0031, 0032 and 0033. Upon UPGMA (unweighted pair-group method with arithmetic averages) analysis of 86 RAPD-PCR markers generated by 16 informative primers and 44 markers obtained with eight microsatellite primers, a close relatedness was evident for F.o.r.l. isolates in VCGs 0090, 0092, 0096, and, to a lesser extent, for those in VCG 0093. Representatives of VCG 0091 formed a distinct group, while F.o.r.l. isolates in VCGs 0094 and 0098 were not distinguishable by the tested markers, most of which were also shared by F.o.l. isolates belonging to VCGs 0031 and 0033. F.o.l. isolates in VCGs 0030 and 0032 shared most of the molecular markers. The correlation between RAPD-PCR and microsatellite genetic distance was highly significant (R2 = 0.77; P by Mantel test < 0.001). The molecular variability observed in both formae speciales is discussed in relation to the development of F.o.r.l.- and F.o.l.-specific diagnostic tools. 相似文献
110.
HgEx is an Expert System that addresses the complex problems surrounding the pollution of the Amazon with Hg by informal mining operations. The system integrates information on biology, chemistry, geochemistry, medical, social and political issues in order to evaluate contamination for a single site or region. The program attempts to diagnose the possibility of hazardous Hg transformations such as oxidation and methylation. An extensive tutorial section containing over 1500 electronic pages provides guidelines for Hg monitoring fieldwork, sampling and analytical steps, amalgamation practices improvements and remelioration procedures for a polluted site. The system is structured for use by either highly-skilled personnel or those without technical-training. 相似文献