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491.
da Silva Franco CC de Sant' Anna JR Rosada LJ Kaneshima EN Stangarlin JR De Castro-Prado MA 《Phytopathology》2011,101(8):923-928
Heterokaryosis is an important mechanism which provides genetic variability increase in filamentous fungi. In order to assess the diversity of vegetative compatibility reactions existing among Colletotrichum acutatum isolates derived from different hosts, complementary nit mutants of each isolate were obtained and paired in all possible combinations. Vegetative compatibility groups (VCG) were identified among the isolates according to their ability to form viable heterokaryons. Seven VCGs were identified among the isolates, one of which contained isolates from different hosts. VCGs 2 and 6 contained two and three members, respectively; VCG-3 contained four members, and four VCGs (1, 4, 5, and 7) contained a single one. This study shows, for the first time, the isolation and the parasexual segregation of a heterozygous diploid sector derived from the heterokaryon formed with nit mutants from VCG-6. Diploid, named DE-3, showed nit+ phenotype and growth rate similar to the parental wild isolate. When inoculated in the presence of the haploidizing agent benomyl, the diploid strain produced parasexual haploid segregants exhibiting the nit phenotypes of the crossed mutants. Since viable heterokaryons and diploid may be formed among vegetative compatible isolates of C. acutatum, this study suggests that the parasexual cycle may be an alternative source of genetic variability in C. acutatum isolates. 相似文献
492.
493.
494.
Carminato A Vascellari M Marchioro W Melchiotti E Mutinelli F 《Veterinary dermatology》2011,22(6):565-569
A 9-year-old, neutered male cat was presented for a subcutaneous mass on the neck. After surgical removal of the mass, a pet identification microchip was found within the tumour. Histological examination of the mass revealed typical features of the feline postinjection sarcoma. The cat had never received injections at the tumour site; all routine vaccinations were administered in the hindlimbs. Few cases of sarcomas developing at the site of microchip application have been reported in animals, although the contributory role of vaccine administrations has not been ruled out. This is the first report of a microchip-associated fibrosarcoma in a cat. Adherence to American Association of Feline Practitioners vaccination guidelines, avoiding the interscapular area, enabled confirmation of the definitive aetiology of the neoplasia. 相似文献
495.
Pistil abortion is considered to be an evolutionary adaptation to save resources in andromonoecious species, balancing the number of pistils with the resources available. It follows that large-fruited species/cultivars should have greater levels of pistil abortion. Working in olive, we found that pistil abortion, expressed as percentage of staminate flowers, was positively correlated to the average ovary mass at bloom, across cultivars with different ovary/fruit mass. Since ovary mass correlated with fruit mass, pistil abortion also correlated with fruit mass. The absolute number of perfect flowers per inflorescence was negatively correlated with both ovary mass and pistil abortion, while the number of staminate flowers per inflorescence increased with both parameters. The total number of flowers (i.e. staminate + perfect) was not correlated to ovary mass or pistil abortion, suggesting that male function was not affected. The results support the hypothesis that pistil abortion is related to competition for resources among ovaries, and suggest that genetic differences in pistil abortion among olive cultivars may be explained by their different pistil mass and sink strength. 相似文献
496.
Robert P. Walker Franco Famiani Alessandro Baldicchi Juan G. Cruz-Castillo Paolo Inglese 《Scientia Horticulturae》2011
The aim of this study was to investigate changes in the abundance of a number of enzymes in the peel, core and seeds of fruits of Opuntia ficus-indica (L.) Miller during development. The enzymes studied were phosphoenolpyruvate carboxylase (PEPC; EC: 4.1.1.31), ribulose-1,5-bisphosphate carboxylase/oxygenase (RUBISCO; EC: 4.1.1.39), aldolase (EC: 4.1.2.13), pyruvate, orthophosphate dikinase (PPDK; EC: 2.7.9.1), phosphoenolpyruvate carboxykinase (PEPCK; EC: 4.1.1.49) and aspartate aminotransferase (AspAT; EC: 2.6.1.1). To detect these enzymes, antibodies specific for each enzyme were used to probe Western blots of sodium dodecyl sulphate polyacrylamide gels. Fruit weight increased throughout development, and during ripening there was both an accumulation of total soluble solids and a decrease in both total titratable acidity and chlorophyll content. In the early stages of its growth the polypeptide pattern and enzyme composition of the fruit chlorenchyma was similar to that of the cladode. In the peel of the fruit PEPC, RUBISCO, plastidic aldolase and PPDK decreased to undetectable amounts as ripening progressed. PEPCK was not detected in either the chlorenchyma of the fruit or cladode. This showed that O. ficus-indica is not a PEPCK type CAM plant and that in this fruit PEPCK is not involved in the metabolism of organic acids. Cytosolic aldolase and AspAT were present in both the peel and core throughout development. The seeds accumulated storage proteins before the fruit ripened, and the abundance of all the enzymes studied declined once the accumulation of storage proteins was complete. 相似文献
497.
Vincenzo Mollace Iolanda SaccoElzbieta Janda Claudio MalaraDomenica Ventrice Carmen ColicaValeria Visalli Saverio MuscoliSalvatore Ragusa Carolina MuscoliDomenicantonio Rotiroti Franco Romeo 《Fitoterapia》2011,82(3):309-316
Bergamot juice produces hypolipemic activity in rats though the mechanism remains unclear. Here we investigated on the effect of bergamot extract (BPF) in diet-induced hyperlipemia in Wistar rats and in 237 patients suffering from hyperlipemia either associated or not with hyperglycaemia. BPF, given orally for 30 days to both rats and patients, reduces total and LDL cholesterol levels (an effect accompanied by elevation of cHDL), triglyceride levels and by a significant decrease in blood glucose. Moreover, BPF inhibited HMG-CoA reductase activity and enhanced reactive vasodilation thus representing an efficient phytotherapeutic approach in combating hyperlipemic and hyperglycaemic disorders. 相似文献
498.
Fabrizio Costa Luca Cappellin Sara Longhi Walter Guerra Pierluigi Magnago Duilio Porro Christos Soukoulis Silvio Salvi Riccardo Velasco Franco Biasioli Flavia Gasperi 《Postharvest Biology and Technology》2011,61(1):21-28
Texture of apple fruit originates from anatomic traits related to cell wall architecture and is one of its most important quality characteristics, thus there is the desire to better understand the different factors which contribute to apple texture. Here we present a novel approach based on the simultaneous profiling of the mechanical and acoustic response of the flesh tissue to compression, using a texture analyzer coupled with an acoustic device. The methodology was applied to a 86 different apple cultivars, measured after two months postharvest cold storage and characterised by 16 acoustic and mechanical parameters. Statistical treatment of the data with principal component analysis (PCA) allowed for the identification of three groups of variables, the mechanical ones being clearly distinguished from the acoustic ones. Moreover, the distribution of the apple cultivars in the multivariate PCA plot allowed characterisation of the cultivars according to their textural performance. Each cultivar was analyzed also with non-destructive vis/NIR spectroscopy in order to determine impartially the ripening stage. Sensory evaluation by panellists was performed on a selected group of cultivars and sensory data correlated with the acoustic-mechanical data. The results demonstrate the good performance of our combined acoustic-mechanical strategy in measuring apple crispness as it is perceived by human senses. 相似文献
499.
Rene S Hendriksen Dik J Mevius Andreas Schroeter Christopher Teale Danièle Meunier Patrick Butaye Alessia Franco Andra Utinane Alice Amado Miguel Moreno Christina Greko Katharina St?rk Christian Berghold Anna-Liisa Myllyniemi Dariusz Wasyl Marianne Sunde Frank M Aarestrup 《Acta veterinaria Scandinavica》2008,50(1):28
Background
The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003–2005, with the aim to establish a continuous monitoring of antimicrobial susceptibility among veterinary laboratories in European countries based on validated and harmonised methodologies. Available summary data of the susceptibility testing of the bacterial pathogens from the different laboratories were collected.Method
Antimicrobial susceptibility data for several bovine pathogens were obtained over a three year period (2002–2004). Each year the participating laboratories were requested to fill in excel-file templates with national summary data on the occurrence of antimicrobial resistance from different bacterial species.A proficiency test (EQAS – external quality assurance system) for antimicrobial susceptibility testing was conducted each year to test the accuracy of antimicrobial susceptibility testing in the participating laboratories. The data from this testing demonstrated that for the species included in the EQAS the results are comparable between countries.Results
Data from 25,241 isolates were collected from 13 European countries. For Staphylococcus aureus from bovine mastitis major differences were apparent in the occurrence of resistance between countries and between the different antimicrobial agents tested. The highest frequency of resistance was observed for penicillin. For Mannheimia haemolytica resistance to ampicillin, tetracycline and trimethoprim/sulphonamide were observed in France, the Netherlands and Portugal. All isolates of Pasteurella multocida isolated in Finland and most of those from Denmark, England (and Wales), Italy and Sweden were susceptible to the majority of the antimicrobials. Streptococcus dysgalactiae and Streptococcus uberis isolates from Sweden were fully susceptible. For the other countries some resistance was observed to tetracycline, gentamicin and erythromycin. More resistance and variation of the resistance levels between countries were observed for Escherichia coli compared to the other bacterial species investigated.Conclusion
In general, isolates from Denmark, England (and Wales), the Netherlands, Norway, Sweden and Switzerland showed low frequencies of resistance, whereas many isolates from Belgium, France, Italy, Latvia and Spain were resistant to most antimicrobials tested. In the future, data on the prevalence of resistance should be used to develop guidelines for appropriate antimicrobial use in veterinary medicine. 相似文献500.
Rene S Hendriksen Dik J Mevius Andreas Schroeter Christopher Teale Eric Jouy Patrick Butaye Alessia Franco Andra Utinane Alice Amado Miguel Moreno Christina Greko Katharina DC St?rk Christian Berghold Anna-Liisa Myllyniemi Andrzej Hoszowski Marianne Sunde Frank M Aarestrup 《Acta veterinaria Scandinavica》2008,50(1):19