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61.
62.
Production and characterization of monoclonal antibodies specific for bovine gamma-interferon 总被引:2,自引:0,他引:2
P R Wood J S Rothel P G McWaters S L Jones 《Veterinary immunology and immunopathology》1990,25(1):37-46
Nine stable hybridoma cell lines were established which secreted specific monoclonal antibodies (MAbs) to bovine gamma-interferon (BoIFN-gamma). Specific binding of each of the MAbs to recombinant BoIFN-gamma (rBoIFN-gamma) was demonstrated in an indirect ELISA, whilst none of the MAbs bound to rBoIFN-alpha or rBoIFN-beta. In a Western blot the MAbs reacted with the 16 kDa and 32 kDa polypeptides present in rBoIFN-gamma preparations. Competitive ELISA's showed that four MAbs bound to one epitope on rBoIFN-gamma, and the other five MAbs bound to a separate epitope. Two MAbs, each recognising different epitopes, were shown to neutralise the anti-viral activity of natural BoIFN-gamma. 相似文献
63.
64.
Summary Four varieties of lupins were sown at three planting dates and the level of Phomopsis leptostromiformis measured on the mature stems. When averaged over planting dates the varieties did not differ in resistance to this disease, however there were highly significant interactions between varieties and planting dates for level of disease. The implications of this result for resistance breeding to Phomopsis leptostromiformis are discussed. 相似文献
65.
A L Patey M Sharman R Wood J Gilbert 《Journal of the Association of Official Analytical Chemists》1989,72(6):965-969
Sixteen United Kingdom analytical laboratories participated in an evaluation of 3 commercially available enzyme-linked immunosorbent assay (ELISA) kits for analysis of aflatoxin in peanut butter. Each laboratory was sent 3 sets of 10 randomly numbered samples of peanut butter. Each set consisted of 5 pairs of undisclosed duplicates. Four of the sets of duplicates were naturally contaminated butters with "target" aflatoxin values (estimated by liquid chromatography) between 8 and 81 micrograms/kg. The fifth pair was a blank peanut butter containing approximately 3 micrograms/kg of total aflatoxins. A statistical treatment of the results of the study is presented, together with discussion of the relative merits of the different kits. 相似文献
66.
Ronald A. Wood Margaret D. Burchett Ralph Alquezar Ralph L. Orwell Jane Tarran Fraser Torpy 《Water, air, and soil pollution》2006,175(1-4):163-180
Volatile organic compounds (VOCs) are major contaminants of indoor air, with concentrations often several times higher than outdoors. They are recognized as causative agents of “building-related illness” or “sick-building syndrome”. Our previous laboratory test-chamber studies have shown that the potted-plant/root-zone microorganism microcosm can eliminate high concentrations of air-borne VOCs within 24 hours, once the removal response has been induced by an initial dose. However, the effectiveness of the potted-plant microcosm in ‘real-world’ indoor spaces has never previously been tested experimentally. This paper reports the results of a field-study on the effects of potted-plant presence on total VOC (TVOC) levels, measured in 60 offices (12 per treatment), over two 5–9 week periods, using three planting regimes, with two ‘international indoor-plant’ species. Fourteen VOCs were identified in the office air. When TVOC loads in reference offices rose above 100 ppb, large reductions, of from 50 to 75% (to <100 ppb), were found in planted offices, under all planting regimes The results indicate that air-borne TVOC levels above a threshold of about 100 ppb stimulate the graded induction of an efficient metabolic VOC-removal mechanism in the microcosm. Follow-up laboratory dose-response experiments, reported in the following paper, confirm the graded induction response, over a wide range of VOC concentrations. The findings together demonstrate that potted-plants can provide an efficient, self-regulating, low-cost, sustainable, bioremediation system for indoor air pollution, which can effectively complement engineering measures to reduce indoor air pollution, and hence improve human wellbeing and productivity. 相似文献
67.
The responses of six strains of R. trifolii to pH, Ca, Al and phosphate were studied in the defined medium of Munns and Keyser (1981) supplemented with vitamins. Wild-type strains responded in the same way as rifampicin-resistant mutant strains. Multiplication was inhibited by acidity alone at pH4.3, and by 50 μM Al at pH 5.5 (despite the precipitation of Al). This inhibitory effect of Al was overcome by increasing the pH above 6.0, or by increasing the phosphate concentration from 10 to 100 μm. Ca concentration had no effect, nor did holding the medium at 22°C for 36 weeks before inoculation. There was variation between strains in their responses to concentrations of A1 < 50 μM. These responses indicate that the defined medium is a satisfactory model for the white clover rhizosphere.Results from these studies and from chemical analyses indicate that the inhibitory effect of Al under partially-neutralized conditions is not due to a direct effect of monomeric A1, nor to an indirect effect of polymeric A1 in reducing the concentration of phosphate, but is due to a direct effect of polymeric A1. 相似文献
68.
M T Knight D W Wood J F Black G Gosney R O Rigney J R Agin C K Gravens S M Farnham 《Journal of the Association of Official Analytical Chemists》1990,73(5):729-733
Twelve laboratories evaluated the Gram-Negative Identification (GNI) Card to identify members of the Enterobacteriaceae. Eighty-four isolates, previously isolated from foods, were used in the collaborative study; the isolates represented 12 genera within the Enterobacteriaceae group. Each collaborator streaked each isolate on tryptic soy agar plates for purity. In the method, plates are incubated 18-24 h at 35 degrees C. Isolated colonies are then subcultured to tryptic soy agar slants and incubated 18-24 h at 35 degrees C. An emulsion is made from the growth on the slant in 1.8 mL 0.45% sodium chloride solution. The GNI Card is filled and placed in a reader/incubator. Isolates are identified and an identification is printed. The Vitek System correctly identified 96.7% of Salmonella sp., 97.0% of Escherichia coli, and an average of 93.8% of the other enteric genera. The method using the Vitek System and GNI Card has been approved interim official first action by AOAC as a screening method for the presumptive identification of Salmonella sp., E. coli, and other Enterobacteriaceae isolated from foods. 相似文献
69.
Juan Valencia Chris Harwood Russell Washusen Andrew Morrow Matthew Wood Peter Volker 《Wood Science and Technology》2011,45(1):15-34
Peripheral longitudinal growth strain (LGS) was measured on a total of 81, 22-year-old pruned Eucalyptus nitens trees from five thinning treatments in a plantation thinning trial in Tasmania. Growth strain data were gathered at breast
height on each tree using the CIRAD-Forêt method. The effects of thinning treatment and tree diameter on LGS and its relationships
to solid-wood traits determined in a processing trial were examined. LGS was significantly higher in the direction of the
prevailing wind and was not significantly affected by either thinning treatment or tree diameter. An index of log end splitting
was positively related to tree diameter, sawlog position (upper/lower), and LGS, which explained up to an additional 20% of
the variance after tree diameter and log position were accounted for in a linear regression model. High LGS and log end splitting
were significant indicators of increased board end splitting. 相似文献
70.
试验结果表明 ,温室后墙悬挂反光膜进行补光后 ,对温室内测定点处最大光照度值无影响 ,但平均提高测定点处水平光照度值 15 4 8% ;温室内凌晨时气温、地温、墙温和被反光膜遮掩处墙温分别比对照温室低 1 1℃、1 5℃、0 9℃和 1 8℃ ,但正午时分别比对照温室高 1 6℃、1 4℃、0 3℃和低 11 4℃。温室经济产量增加 7 4 % ,当期经济效益增加 2 1元 /m2 。 相似文献