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41.
Aliphatic primary and biogenic amines of grape varieties from two vintages were studied. We established that appearance and/or increase of both primary aliphatic and biogenic amines is due to microbiota living in/on grape berries. Aszú, gray rotten grapes infected mainly with Botrytis cinerea, grape berries infected mainly with Penicillium species, and intact grape berries were compared on the basis of amine composition using t-test, analysis of variance, and multivariate statistical analysis (principal component analysis and linear discriminant analysis). The amine composition and amine content of Aszú grapes were significantly different (p < 0.05) from those of intact grapes despite the effect of the vineyards and the vintages. Grape samples coming from the same growing location, intact, Aszú grapes, and grape berries infected mainly with Penicillium species could be separated from each other with multivariate statistical analysis. We distinguished intact, Aszú (noble rotten), and gray rotten berries from each other as well. Evaluating amine values of grape samples independently of the place of origin, the Aszú and green rotten berries could not be differentiated. The varieties and vineyards have affected the amine composition of Aszú grapes, while these effects on intact grapes appeared only slightly.  相似文献   
42.
Successful control of livestock diseases requires an understanding of how they spread amongst animals and between premises. Mathematical models can offer important insight into the dynamics of disease, especially when built upon experimental and/or field data. Here the dynamics of a range of epidemiological models are explored in order to determine which models perform best in capturing real-world heterogeneities at sufficient resolution. Individual based network models are considered together with one- and two-class compartmental models, for which the final epidemic size is calculated as a function of the probability of disease transmission occurring during a given physical contact between two individuals. For numerical results the special cases of a viral disease with a fast recovery rate (foot-and-mouth disease) and a bacterial disease with a slow recovery rate (brucellosis) amongst sheep are considered. Quantitative results from observational studies of physical contact amongst domestic sheep are applied and results from the differently structured flocks (ewes with newborn lambs, ewes with nearly weaned lambs and ewes only) compared. These indicate that the breeding cycle leads to significant changes in the expected basic reproduction ratio of diseases. The observed heterogeneity of contacts amongst animals is best captured by full network simulations, although simple compartmental models describe the key features of an outbreak but, as expected, often overestimate the speed of an outbreak. Here the weights of contacts are heterogeneous, with many low weight links. However, due to the well-connected nature of the networks, this has little effect and differences between models remain small. These results indicate that simple compartmental models can be a useful tool for modelling real-world flocks; their applicability will be greater still for more homogeneously mixed livestock, which could be promoted by higher intensity farming practices.  相似文献   
43.
Faba bean is an excellent candidate crop to provide nitrogen input into temperate agricultural systems. However, its growth is hampered by several factors including environmental stresses and the presence of anti-nutritional factors. To solve these limitations, breeding programs have been initiated that were successful for monogenic traits but not so for multigenic traits. The large genome size of faba bean has slowed down breeding processes. Several other legumes have emerged as model legumes including Medicago truncatula, Lotus japonicus, Glycine max and Pisum sativum. The establishment of these models has already boosted our understanding of important processes such as the nitrogen-fixing symbiotic interaction. The high level of synteny and collinearity existing between legumes makes possible the transfer of key knowledge from model legumes to faba bean. Here we review the most recent knowledge gained from model legumes on grain quality, resistance to biotic and abiotic stresses, nitrogen-fixing symbiosis and how this knowledge can be employed for faba bean breeding.  相似文献   
44.
Swine influenza virus isolates originating from outbreaks in Sweden from 1983, 2002 and 2009 were subjected to nucleotide sequencing and phylogenetic analysis. The aim of the studies was to obtain an overview on their potential relatedness as well as to provide data for broader scale studies on swine influenza epidemiology. Nonetheless, analyzing archive isolates is justified by the efforts directed to the comprehension of the appearance of pandemic H1N1 influenza virus. Interestingly, this study illustrates the evolution of swine influenza viruses in Europe, because the earliest isolate belonged to ''classical'' swine H1N1, the subsequent ones to Eurasian ''avian-like'' swine H1N1 and reassortant ''avian-like'' swine H1N2 lineages, respectively. The latter two showed close genetic relatedness regarding their PB2, HA, NP, and NS genes, suggesting common ancestry. The study substantiates the importance of molecular surveillance for swine influenza viruses.  相似文献   
45.
In this study, for the first time, we used the in vitro metallopeptidase model for the identification of a potential novel activity of defatted evening primrose seed extracts. Prepared extracts of different polarity (aqueous, 60% ethanolic, isopropanolic, and 30% isopropanolic) at concentrations of 1.5-100 microg/mL exhibited a significant and dose dependent inhibition of three tested enzymes. The 50% inhibition of enzymes activity showed that aminopeptidase N (APN) was the enzyme affected to the greatest extent with IC50 at the level of 2.8 microg/mL and 2.9 microg/mL for aqueous and 30% isopropanolic extracts, respectively. The activity of neutral endopeptidase (NEP) was quite strongly inhibited by the extracts as well. The HPLC-DAD analysis and bioguided fractionation led to the identification of four active compounds: (-)-epicatechin gallate, proanthocyanidin B3, oenothein B, and penta-O-galloyl-beta-D-glucose (PGG). Oenothein B has been shown previously to inhibit metallopeptidases. The three other compounds are known to inhibit angiotensin-converting enzyme (ACE), but they have not been previously reported to inhibit the NEP and APN activity. PGG and procyanidins with different degrees of polymerization, as the dominating compounds in O. paradoxa seeds, seemed to play a role in the crude extract activity.  相似文献   
46.
47.
1. Concentration of noradrenaline, adrenaline and dopamine in eight hypothalamic nuclei or areas (nucleus hypothalamicus medialis anterior, n. periventricularis magnocellularis, n. hypothalamicus lateralis anterior, n. hypothalamicus medialis posterior, n. hypothalamicus lateralis posterior, eminentia medialis, n. tuberis, area hypothalamica posterior) have been determined by a sensitive radioenzymatic micromethod in male Japanese quail restrained for 30 min.

2. In control quail the highest concentrations were found in the a. hypothalamica posterior, n. periventricularis magnocellularis and n. hypothalamicus medialis anterior; the lowest was in the n. hypothalamicus medialis posterior.

3. After restraint, noradrenaline concentrations decreased in the n. periventricularis magnocellularis and n. hypothalamicus medialis posterior. However, the concentration of adrenaline increased in the n. tuberis under the same conditions. In stressed animals the dopamine concentration was lower than in controls in the n. periventicularis and higher in the n. tuberis.  相似文献   

48.
49.
Our objectives were to improve the rate of haploid plant regeneration through increasing the rate of callus initiation on the anthers and sustaining shoot regeneration frequency, and to analyze the field population of anther culture origin by morphological and molecular methods. Regarding the callus initiation, the most responsive clones were ‘N-90’(59%) in P. nigra and ‘D-29’ (75%) in P. deltoides. The rate of shoot regeneration and number of shoots/calli ranged from 4%–79% and 1–9, respectively. From the 208 rooted plants 8 haploid, 179 diploid, 4 tetraploid and 17 aneuploid plants were found. In the field population, the haploid plants could be easily identified by their retarded development and morphological characteristics (size and shape of the leaves, strong branching, etc). Several diploid plants showed depressed developmental and morphological traits similar to the haploid ones. Three traits (growth rate, leaf blade length and shape of leaf base) of the 6 different morphological characteristics measured were in correlation with the ploidy level within the poplar field population. Six primers of the 48 primers tested were able to detect polymorphism among the field plants. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
50.
Summary Morphological characterization of 20 common millet (Panicum miliaceum L., 2n = 4x = 36) cultivars and landraces revealed four distinct clusters which were apparently consistent with the grain colors of black, black and brown, red, yellow, and white. Seed remains of medieval millet, recovered from a 15th century layer (King's Palace, Budapest, Hungary), showed reddish yellow grain color after rehydrating on tissue culture medium that was close to grain color of modern cultivar Omszkoje. aDNA of medieval commom millet was extracted successfully, analyzed and compared to modern common millets by ISSR, SSR, CAP and mtDNA. Analyses of fragments and sequences revealed polymorphism at seven ISSR loci (15 alleles) and at the 5S-18S rDNA locus of mtDNA. CAP analysis of the 5S-18S rDNA fragment revealed no SNPs in the restriction sites of six endonucleases TaqI, BsuRI, HinfI, MboI, AluI and RsaI. Sequence alignments of the restriction fragments RsaI also revealed consensus sequence in the medieval sample compared to a modern variety. An attempted phenotype reconstruction indicated that medieval common millet showed the closest morphological similarity to modern millet cultivar Omszkoje.  相似文献   
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