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101.
102.
Background: A new commercial gel column agglutination system is reported to have high sensitivity in detecting cats with blood type AB. Objectives: The aims of this study were to compare gel column agglutination and card agglutination methods for feline blood‐typing and to determine the frequency distribution of feline blood types in northern Italy. Methods: Blood‐typing was performed on 120 cats using both a commercial gel column containing monoclonal antibodies (ID Gel‐Test Micro Typing System) and a card agglutination method (RapidVet‐H Feline). Results were confirmed with back‐typing. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the 2 methods. A second group of 140 Domestic Shorthair (DSH) cats was blood‐typed using the gel column technique to determine the frequency distribution of feline blood types in northern Italy. Results: The card agglutination method demonstrated poor sensitivity in identification of type‐AB cats (61%) and was only 95% specific when identifying type‐B cats. The gel column agglutination technique demonstrated 100% sensitivity and specificity for typing all 3 blood types (A, B, and AB). The frequency distribution study of 140 cats demonstrated that 127 (90.7%) cats were type A, 10 (7.1%) were type B, and 3 (2.1%) were type AB. Conclusion: When blood‐typing cats of breeds with a relatively high frequency of blood types B and AB, methods that use monoclonal antibodies for detection of blood types B and AB are recommended. Alternatively, blood type can be confirmed by more sensitive supplemental testing, such as back‐typing. The high frequency of blood type A in DSH cats in northern Italy was comparable to previously reported frequencies in Italy and world‐wide.  相似文献   
103.
Neboviruses are bovine enteric caliciviruses (genus Nebovirus) associated with enteric diseases in calves. By screening the stools of calves collected from Italian herds using primers targeted to a conserved stretch in calicivirus RNA-dependent RNA-polymerase (RdRp), nebovirus RNA was detected in calves with enteritis (13.1%) but not in overtly health animals. Upon sequence analysis of the RdRp fragment, the Italian viruses formed a tightly conserved group and resembled closely the nebovirus prototype Nebraska/80/US. The sequence of a 2.2kb ORF1 fragment, spanning the 3' end of the RdRp and the full-length capsid coding region, of two nebovirus strains was determined, revealing marked genetic heterogeneity in the capsid protein, as the two Italian viruses were classified into two distinct capsid lineages, and suggesting a recombination event downstream the highly conserved shell (S) domain.  相似文献   
104.
A study was carried out to evaluate the influence of vitamin and trace mineral supplementation on milk production and composition in grazing dairy ewes during the dry season. Ewes (n = 50) were assigned at weaning to blocks and treatments. Ewes were daily conducted (8 h/day) on a pasture based on Italian ryegrass (Lolium multiflorum). At fold, ewes received a basal diet composed by ad libitum oat hay and a definite amount of a pelleted concentrate. Dietary treatments included: (1) the control concentrate containing background of vitamin and trace mineral only, and (2) the experimental concentrate containing the premix supplement (10 g/kg of dry matter). Vitamin and trace mineral supplementation did not affect ewes’ body weight. Milk, fat- and protein-corrected milk, fat percentage, and clotting properties were improved in ewes fed supplemented concentrate. There was a week × treatment interaction (P < 0.05) for yield of milk and corrected milk that was greatest at peak production in ewes fed the premix. Our findings indicate that in grazing dairy ewe, the dietary vitamin and trace mineral supplementation during dry season led to an increase of milk production and quality, with positive improvement in milk clotting aptitude.  相似文献   
105.
Phase out of most chemicals available for weed management renewed the interest in soil solarization as a technically effective and environmentally safe practice for lettuce weed control in hot summer areas. Properties of solarizing films and lettuce crop system may considerably affect weed control and yield response of soil solarization. Different solarizing films, including low-density polyethylene, ethylene-vinyl acetate copolymer, low-density polyethylene–ethylene-vinyl acetate coextruded and a biodegradable corn starch-based film, were evaluated in 2003 and 2004 for weed control and lettuce yield response under field and greenhouse conditions in Southern Italy. Soil solarization strongly reduced weed density and biomass in both greenhouse and in the field, with no significant differences among the tested plastic films. Most annual weeds were completely controlled by soil solarization, except amaranth, Amaranthus spp., in soil solarized with biodegradable film in the field. Emergence of mediterranean sweetclover, Melilotus sulcatus, was stimulated by soil solarization in greenhouse. In the field, Cyprus vetch, Lathyrus ochrus, was found in solarized plots though absent in untreated soil. Perennial weeds were not affected by soil solarization, except a strong control of canadian thistle, Cirsium arvense, in the field. Lettuce yield resulted significantly higher in solarized soil than in control plots, with no significant differences among the solarizing materials. All tested materials proved to be technically effective for soil solarization in lettuce, though low resistance and short durability of biodegradable film may suggest its application mainly to soil solarization in greenhouse or in organic systems.  相似文献   
106.
Barley byproducts obtained by air classification have been used to produce a different barley functional spaghetti, which were compared to different commercial whole semolina samples. Total, insoluble, and soluble fiber and β-glucan contents of the barley spaghetti were found to be greater than those of commercial samples. Furthermore, it was proved that barley spaghetti reached the FDA requirements, which could allow these pastas to deserve the health claims "good source of dietary fiber" and "may reduce the risk of heart disease". When the barley coarse fraction was used, a flavan-3-ols enrichment and an increase of antioxidant activity were reported, while commercial samples showed the absence of flavan-3-ols and a higher presence of phenolic acids and tannins. Whole semolina commercial spaghetti had a significantly higher content of phenolic acids than semolina spaghetti samples. Besides, it was observed that when vital gluten was added to the spaghetti formulation, phenolic compounds were blocked in the gluten network and were partially released during the cooking process.  相似文献   
107.
Fifteen microsatellite loci were used to genotype 108 accessions of cultivated olive, Olea europaea L. ssp. europaea var. europaea, and eight of O. europaea L. ssp. cuspidata (Wall. ex G. Don) Ciferri, from the germplasm collection of the United States Department of Agriculture in Davis, California. Number of alleles per locus ranged from 3, for locus IAS-pOe12_A, to 16, for locus ssrOeUA-DCA11, with an overall mean of 9.93. Observed heterozygosity ranged from 0.175, for locus UDO99–019, to 0.937, for locus GAPU89, with a mean of 0.640. The cluster analysis using the Unweighted Pair Group Method using Arithmetic mean (UPGMA) method displayed thirteen clusters within seven main groups that can be partially described by common geographic origin or fruit use, though overlap among these groups was common. The locus-wise total gene diversity (H T) ranged from 0.319, at UDO99–019, to 0.847, at ssrOeUA-DCA3, with an overall mean of 0.696. Most of the gene diversity was partitioned within clusters, with proportions (H S/H T) ranging from 0.633, at IAS-pOe12_B, to 0.848 at GAPU89 per locus, with a mean of 0.759. The principal components analysis explained 24.8% of the total variation along the first two components. Projection of accessions onto the first two principal components produced affinities generally in agreement with the results of the UPGMA cluster analysis. The California cultivar ‘Mission’ clustered closely with Iberian cultivars and may represent clonal selections adapted to local growing conditions. The results show significant diversity but low levels of differentiation among olive cultivars within the collection.  相似文献   
108.
Organic amendment and tillage reduction are two common practices to contrast soil organic matter decline, thus promoting sustainable cropping and carbon sequestration. In a horticultural land use system under Mediterranean climate, we evaluated the 9-year effects of two compost inputs (15 and 30 t ha−1 y−1, low and high input, respectively) and two tillage intensities (intensive and reduced) on soil macronutrients concentration, microbial biomass and activity. Total organic C, total N and POlsen were smaller in plots amended at low input, whilst intensive tillage decreased them at both compost inputs. These decreases in intensively tilled plots was ascribed to the disruption of soil aggregates, with consequent microbial degradation of the physically protected organic matter by oxidative processes. On the contrary, reduced tillage increased the extractable C, likely due to a higher protection of the most labile soil C fraction from the mineralization. Similarly, microbial biomass C and N increased following both doubling compost input and reducing tillage intensity, with a greater effect by the first factor. The higher values of cumulative 10-day basal and 20-h glucose-induced respiration, and metabolic quotient in intensively tilled plots suggested that high tillage favoured soil aggregate disruption and C accessibility. This was also confirmed by higher values of dehydrogenase activity/total organic C in those plots. Intensive tillage caused a higher soil aeration and organic substrates accessibility to microflora, thus undoing the fertility benefits provided by the high compost input. However, also a low compost input coupled to reduced tillage seemed to accomplish soil sustainability needs.  相似文献   
109.
110.
The mechanism of modulation of the Na/H antiport was studied in erythrocytes of the tilapia, Oreochromis mossambicus. Activation of the antiport was determined through measurements of variations of intracellular pH, using a pH-sensitive, intracellular fluorescent probe 2′, 7′-bis (carboxyethyl)-5 (6)-carboxyfluorescein (BCECF). Phorbol ester (5 μM), a stimulator of protein kinase C, activated the antiport resulting in an increase of intracellular pH; a maximum of 0.125 ± 0.027 pH units over basal level (mean ± SD; n = 4–6) was reached in 20 min. The effect was blocked by protein kinase C inhibitors staurosporine and H-7, and also by the antiport inhibitor 5-(ethyl-N-isopropyl) amiloride; this demonstrates that the stimulation of the antiport in tilapia erythrocytes can take place through a protein kinase C-mediated mechanism. Vasopressin, an important osmoregulator hormone in teleosts, was able to activate the Na/H antiport, in a manner similar to phorbol ester, but its effect was only partially sensitive to staurosporine inhibition. Considering that the physiological role of the Na/H exchanger in fish is known to be different from its role in mammalian cells, these results indicate that other signal transduction mechanisms can be involved in the modulation of intracellular pH by vasopressin. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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