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81.
82.
Decaro N Mari V von Reitzenstein M Lucente MS Cirone F Elia G Martella V King VL Di Bello A Varello K Zhang S Caramelli M Buonavoglia C 《Veterinary microbiology》2012,159(1-2):239-244
We report the genetic and biological characterisation of a novel pantropic canine coronavirus (CCoV), strain 450/07, which caused the death of a 60-day-old miniature pinscher. At the genetic level, this virus was strictly related to the prototype strain CB/05, but displayed some unique features. After experimental infection with the new pantropic isolate, most inoculated dogs showed diarrhoea and acute lymphopenia. Gross lesions and histological changes were mainly evident in the gut and lymphoid tissues, although some animals showed remarkable changed also in parenchymatous organs. The viral RNA was detected in the faeces and/or internal organs of most pups. These findings seem to indicate that strain 450/07 is able to spread to internal organs (mainly lymphoid tissues), causing lymphopenia but inducing a mild disease. 相似文献
83.
Previous simulations of a self-avoiding, closed random surface with restricted topology (without handles) on a three-dimensional lattice have shown that its behavior on long length scales is consistent with that of a branched-polymer. It is shown analytically that such a surface with an unrestricted number of handles has a qualitatively different geometry and therefore is in a different universality class. The effect of a net external pressure is to suppress the handles and collapse the surface into a branched polymer-like configuration. Topology is thus shown to be a key factor in determining the universality class of the system. 相似文献
84.
Maria Stella Grando Luigi De Micheli Attilio Scienza 《Genetic Resources and Crop Evolution》1996,43(2):187-192
Summary An analysis of the amplification fragments polymorphism of DNA coming from different accessions of germplasm belonging to species and cultivars of the genus Vitis, was carried out using 40 primer decamers of arbitrary sequence. The RAPD profiles showed a great intraspecific diversity. In many cases a single primer produced a unique pattern for each species. A phylogram tree based upon presence/absence data of the principal DNA bands divided the species according to their geographical origins. The intraspecific polymorphism of DNA fragments was not sufficient for an unambiguous identification of Vitis vinifera cultivars but the RAPD profiles turned out to be highly reproducible. The high capacity of this technique to generate DNA markers offers a new possibility for the study of the genetic relationships in the genus Vitis.Abbreviations PCR
Polymerase chain reaction
- RAPD
Random amplified polymorphic DNA 相似文献
85.
Carnosine (beta-alanyl-L-histidine) is a dipeptide found in the muscle foods that has been postulated to be a bioactive food component. The objective of this research was to determine the concentration of carnosine in human plasma after ingestion of beef. Nine males and nine females were recruited for the study. Food devoid of meat products was given to the subjects so that they did not consume carnosine for 48 h prior to the test. Subjects fasted for 12 h and then had blood withdrawn prior to a meal containing 200 g of ground beef. Additional blood samples were collected over the following 24 h and carnosine concentrations were determined by HPLC. The cooked ground beef used in the study contained 52% water, 24% protein, 22% fat, and 124 mg of carnosine/100 g of beef. No plasma carnosine was detected in subjects before the consumption of the beef. Carnosine was detected in plasma 15 min after beef consumption. Plasma carnosine concentrations continued to increase with a maximum (32.7 mg of carnosine/L of plasma) being recorded 2.5 h after consumption. Carnosine concentrations then decreased until no carnosine could be detected at 5.5 h postconsumption. These results indicate that dietary carnosine is absorbed into human plasma after the consumption of beef. Since carnosine has several potential health benefits, evidence of its bioavailability suggests that it could be a bioactive food component. 相似文献
86.
Christophoridou S Dais P Tseng LH Spraul M 《Journal of agricultural and food chemistry》2005,53(12):4667-4679
This study reports the first application of the hyphenated LC-SPE-NMR technique using postcolumn solid-phase extraction to the direct analysis of phenolic compounds in the polar part of olive oil. Apart from the identification and structure elucidation of simple phenols (hydroxytyrosol, tyrosol, vanillic acid, vanillin, p-coumaric acid, hydroxytyrosol, and tyrosol acetates), lignans (pinoresinol and 1-acetoxypinoresinol), flavonoids (apigenin and luteolin), and a large number of secoiridoid derivatives, this technique enables the identification of several new phenolic components, which had not been reported previously as constituents in the polar part of olive oil. 相似文献
87.
Dichloromethane, methanol and aqueous extracts of the aerial parts of Terminalia australis were evaluated for their antifungal activity. The methanol and aqueous extracts were found to be effective against the tested Aspergillus and Candida strains. 相似文献
88.
Pereyra CM Cavaglieri LR Chiacchiera SM Dalcero AM 《Veterinary research communications》2011,35(6):367-379
The aim of the present study was to determine the mycobiota and natural levels of mycotoxins such as zearalenone, fumonisin
B1, aflatoxin B1 and ochratoxin A present in raw materials and finished fattening pig feed. Samples were examined for total fungi and genera
distribution. Zearalenone, FB1, AFB1 and OTA contamination were determined using high pressure liquid chromatography and thin layer chromatography. Milled maize
and finished feed samples showed fungal contamination over than 1 × 104 CFU/g. All samples contained at least one of the main mycotoxigenic genera Aspergillus, Fusarium and Penicillium. A. flavus and F. verticillioides were the most prevalent species. Only some Aspergillus section Nigri strains from suckling pig to growing pig samples were able to produce OTA. A. flavus strains from milled maize, wheat bran, suckling pig to growing pig samples were able to produce AFB1. All samples were positive for FB1. Sucking pig, piglet, growing and boar feed samples showed ZEA natural contamination. AFB1 and OTA contamination were not detected. There was a 100% correlation between FB1 and ZEA contamination in sucking pig, piglet, growing and boar feed samples; 50% piglet samples and 67% suckling pig samples
showed ZEA levels over the recommended limits. The present study has shown the occurrence of two mycotoxins, FB1 and ZEA in feed intended for fattening pig consumption. In animal production, the simultaneous presence of toxicogenic fungi
and low dietary levels of mycotoxins in field conditions can cause possible health impacts and lost performance in pigs from
feeding spoiled feeds. 相似文献
89.
Roberto Confalonieri Simone Bregaglio Alexandra Stella Rosenmund Marco Acutis Igor Savin 《European Journal of Agronomy》2011,34(1):20-25
A reliable approach for modelling rice plant height would allow the simulation of processes with a significant impact on yields, e.g., lodging, floodwater effect on leaves temperature, crop–weeds competition for radiation interception. In this paper we present a new model for the simulation of rice plant height based on the integral of the percentage of biomass partitioned to stems. The model was compared with four alternative approaches using data collected during eight experiments carried out in Russia, Japan and US between 1991 and 2000, proving to be the most accurate in reproducing plant height during the whole crop cycle. RRMSE ranged between 8.02% and 20.87%, modelling efficiency was always close to one and the absolute value of coefficient of residual mass never exceeded 0.16. It resulted also the most robust and the less complex (according to the Akaike's Information Criterion) among those compared. The model presents a lower level of empiricism with respect to the other approaches found in the literature, deriving plant height from the allocation of biomass to stems, which are the plant organs most involved in determining canopy height. This model represents a suitable base for further developments aiming at including the effect of management practices (e.g., fluctuating water depth) and environmental factors (e.g., crop–weeds competition for radiation interception). Moreover, the low input requirements favour its inclusion in operational cropping systems models. 相似文献
90.
Stella Marie Reamon-Büttner Günter Wricke Lothar Frese 《Genetic Resources and Crop Evolution》1996,43(3):261-274
Interspecific relationship among wild beets in section Corollinae was analyzed. Isozyme allele composition supports the concept of three basic species consisting of two diploid species, Beta lomatogona and Beta macrorhiza and the tetraploid species, Beta corolliflora. The polyploid and apomictic species referred to as Beta trigyna and Beta intermedia were found as hybrids. Based on isozyme and RAPD results, B. corolliflora was also found more related to B. macrorhiza than to B. lomatogona. From the phylogenetic trees constructed from isozyme data, B. corolliflora and B. macrorhiza seem to be the end members of the evolutionary line. Analysis of genetic diversity showed that B. corolliflora was more polymorphic and heterozygous than B. lomatogona and B. macrorhiza. Differences between B. macrorhiza accessions from Turkey and Dagestan were found. 相似文献