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41.
SUMMARY An Australian bovine herpesvirus 1 (BHV1) isolate with a defined (427 base pair) deletion in the protein coding region of the thymidine kinase gene was obtained by standard marker rescue procedures. After selection in the presence of the nucleotide analogue 5iodo-deoxy-uridine the virus was analysed by hybridisation with three differential oligonucleotide probes, restriction endonuclease profile studies and DNA sequence analysis. The virus elicited an immune response in recipient animals after either intramuscular or intravenous administration and produced no significant deleterious side-effects when administered at a dose sufficient to stimulate the host immune response. The safety and immunogenicity of the recombinant BHV1 virus 39B1 were similar to those reported for other registered BHV1 vaccines and the virus would appear to be suitable for the production of a vaccine seed lot and more exhaustive field trials as a prelude to commercial vaccine production and registration.  相似文献   
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Increases of plasma concentrations of neutrophil myeloperoxidase (MPO) can be used as markers of polymorphonuclear leucocytes (PMN) activation in pathological situations (sepsis, acute lung injury, acute inflammation). To develop an assay for measurement of plasma MPO in horses during the above-mentioned infectious and inflammatory conditions, MPO was purified from equine PMN isolated from blood anticoagulated with citrate. PMN were extracted in a saline milieu (0.2 M Na acetate, 1 M NaCl, pH 4.7) to eliminate most of cellular proteins. Pellets were then extracted in the same buffer containing cationic detergent (1% cetyltrimethyl ammonium bromide). The supernatant was further purified by ion exchange chromatography (Hiload S Sepharose HP column 0.5 x 26 cm, equilibrated with 25 mM Na acetate, 0.2 M NaCl, pH 4.7) with a NaCl gradient (until 1 M). Most of the peroxidase activity of MPO (spectrophotometrically measured by the oxidation of orthodianisidine by hydrogen peroxide) was eluted at 0.65 M NaCl. MPO was further purified by gel filtration chromatography (Sephacryl S 200 column 2.6 x 42 cm with 25 mM Na acetate, 0.2 M NaCl, pH 4.7). MPO (specific activity: 74.3 U/mg) was obtained with a yield of 30% from the detergent extraction supernatant. Electrophoresis (non-reducing conditions) showed 3 bands identified, by comparison with human MPO, (i) the mature tetrameric enzyme (150 kDa) with 2 light and 2 heavy subunits, (ii) the precursor form (88 kDa) and (iii) a form of the heavy subunit without the prosthetic heme group (40 kDa). The mature enzyme and its precursor were glycosylated and possessed peroxidase activity. Equine MPO showed strong similarities with human and bovine MPO, with an absorption peak at 430 nm (Soret peak) characteristic of ferrimyeloperoxidase. Enzymatic activity was pH dependent (optimal value at pH 5.5).  相似文献   
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本文介绍一种新的饲料配方优化模型一模糊配方模型,利用该模型改进已有配方软件,并将该模型与已有模型进行比较和分析。  相似文献   
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In this study, we compared the analytical fingerprint and bioactivity of three onion extracts, including an aqueous, a methanol, and a fermented aqueous extract. The extracts were characterized by HPLC-DAD, LC-MS, and GC-MS analyses. The antibacterial, antigenotoxic, and antiproliferative activity of these extracts was assessed by means of agar disk diffusion, bacterial growth kinetics, a comet assay, cell cycle distribution analysis, and cell viability testing. Both the aqueous and methanolic extracts showed a typical flavonol-fingerprint as assessed by HPLC measurements and showed little to no bioactivity. The fermented aqueous extract, which lacks the usual onion flavonoid profile, was found to be the most active in all of the assays. This finding indicates that metabolites of onion compounds, generated by lactic acid fermentation, may be more active than their precursor substances.  相似文献   
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Soils irrigated with raw wastewater for many years accumulate trace metals, especially in the surface horizon. We do not know, however, to what extent the metals migrate down the profile and whether they accumulate in deeper horizons. We assessed the migration of trace metals in the suburbs of Paris where market gardens had been irrigated with wastewater for more than 100 years. Within a soil series, we compared metals in the polluted soils with those of a reference soil of the same kind. We sampled by horizons three representative Luvisol profiles in the irrigated area and a fourth profile selected as a reference just outside the irrigated area. Large quantities of Zn, Pb, Cd and Cu appeared to have accumulated in the topsoil, at the base of which concentrations diminished markedly. There appeared to be appreciable migration into the subsoil only at the most intensely irrigated site. By relating the total trace metal contents to the total iron contents we could detect anomalous values and identify migration into the subsurface horizons more sensitively. This approach was tested first with the endogenous metal Cr, then with metal pollutants. We showed that Zn, Pb, Cd and Cu migrated downwards in all three irrigated soils.  相似文献   
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Musty, earthy odors are highly detrimental to the aromatic quality of wines. A characteristic aroma of freshly tilled earth, damp cellar was studied in some red and white wines of different origins. The extraction and purification of the wines marked by this odor have shown after analysis by gas chromatography-olfactometry a unique strong odorous zone having the same odor as the one perceived at tasting. The compound responsible for this odorous zone was identified by gas chromatography-mass spectrometry as geosmin (trans-1,10-dimethyl-trans-9-decalol), which possesses a distinctive earthy odor. Geosmin may be present in wines at levels higher than the racemic geosmin olfactory perception threshold, thus suggesting its contribution to their off-aroma. Moreover, the presence of this compound in juice taken from freshly crushed grapes suggests that microorganisms that develop on the grapes may contribute to the presence of this compound in wines.  相似文献   
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Massive volumes of raw wastewater have been spread on sandy Luvisols in the Paris region since 1899, causing major soil contamination with metallic trace elements (MTE). To identify the factors influencing the vertical and horizontal redistribution of MTE at the plot scale, a study was carried out of the three‐dimensional distribution of zinc. The background and exogenous fractions of zinc in the contaminated soil were discriminated using correlations between zinc and iron defined from unpolluted soils of the area. At the surface, the spatial distribution of zinc is determined by the geometry of the irrigation system and the terrain topography. The highest concentrations are observed near the irrigation outlets and in areas of very slight slope. The exogenous zinc has migrated down to the base of the studied solums (1 m depth), and its subsurface distribution depends upon the physico‐chemical properties of the horizons. In the E horizon, the trapping of exogenous zinc is governed by the number of available reactive sites, whereas in the Bt horizon it is a function of the vertical and lateral behaviour of the drainage. Moreover, lateral transfer of exogenous zinc occurs in the C horizon. In the case of soil contaminated with raw wastewater, the organization of water flow on the surface and in the subsurface is a determining factor in the redistribution of zinc within a plot.  相似文献   
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