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51.
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A. D. J. Watson 《The Journal of small animal practice》1990,31(8):393-397
A female domestic shorthaired cat had frequent seizures and vague gastrointestinal signs. Lead poisoning was suspected because of increased urinary delta aminolevulinic acid concentration. However, abnormalities continued despite repeated chelation therapy and blood lead concentration was normal. Delta aminolevulinic aciduria persisted, but concentrations of porphobilinogen in urine and of porphyrins in blood, urine and faeces were normal. An inherited porphyric disorder was suspected, involving deficiency of aminolevulinic acid dehydrase, an enzyme active in haem biosynthesis. Accumulation of aminolevulinic acid in vivo could explain the observed signs. 相似文献
53.
Vitamin K-dependent multifactor coagulopathy in Devon Rex cats 总被引:1,自引:0,他引:1
J E Maddison A D Watson I G Eade T Exner 《Journal of the American Veterinary Medical Association》1990,197(11):1495-1497
A coagulopathy attributable to a deficiency of vitamin K-dependent clotting factors (II, VII, IX, and X) was diagnosed in 3 Devon Rex cats. There was no evidence for exposure to vitamin-antagonist-related rodenticides. The cats did not have evidence of hepatic disease, gastrointestinal disease, or fat malassimilation. Oral treatment with vitamin K1 resulted in normalization of clotting factor concentrations. However, when treatment was discontinued in 2 cats, prothrombin and activated partial thromboplastin values became prolonged again, although the cats did not have clinical signs of a bleeding disorder. 相似文献
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Riley MB Dumas JA Gbur EE Massey JH Mattice JD Mersie W Mueller TC Potter T Senseman SA Watson E 《Journal of agricultural and food chemistry》2005,53(13):5079-5083
An interlaboratory study was conducted to compare pesticide recovery from Empore C(18) and Speedisks C(18)XF solid phase extraction disks after shipping. Four pesticides were used for the comparison of the two disk extraction materials: atrazine, diazinon, metolachlor, and tebuconazole. These pesticides were chosen to provide a range of physiochemical properties. Water samples were extracted onto the disk types and shipped to a cooperating laboratory for elution and analysis. The mean recoveries from Empore disks were atrazine, 95%; diazinon, 91%; metolachlor, 92%; and tebuconazole, 83%. The recoveries from Speedisks C(18)XF were atrazine, 89%; diazinon, 87%; metolachlor, 86%; and tebuconazole, 79%. Means for each of the pesticides using the different disk types were not statistically different (alpha = 0.05), but results were more variable when using Speedisks C(18)XF as compared to Empore disks. Reasons for the increased variability are discussed, but overall results indicate that Speedisks C(18)XF could be used as an alternative to Empore disks. Speedisks C(18)XF are enclosed in a plastic housing, so they can be used more easily in remote sampling sites without the possibility of glassware breakage, no prefiltration of samples is needed, and there are realignment problems that can be associated with the Empore disks. 相似文献
56.
Managing soil fertility in organic farming systems 总被引:9,自引:0,他引:9
C.A. Watson D. Atkinson P. Gosling L.R. Jackson F.W. Rayns 《Soil Use and Management》2002,18(S1):239-247
Abstract. Complex relationships exist between different components of the organic farm and the quantity and quality of the end products depend on the functioning of the whole system. As such, it is very difficult to isolate soil fertility from production and environmental aspects of the system. Crop rotation is the central tool that integrates the maintenance and development of soil fertility with different aspects of crop and livestock production in organic systems. Nutrient supply to crops depends on the use of legumes to add nitrogen to the system and limited inputs of supplementary nutrients, added in acceptable forms. Manures and crop residues are carefully managed to recycle nutrients around the farm. Management of soil organic matter, primarily through the use of short-term leys, helps ensure good soil structure and biological activity, important for nutrient supply, health and productivity of both crops and livestock. Carefully planned diverse rotations help reduce the incidence of pests and diseases and allow for cultural methods of weed control. As a result of the complex interactions between different system components, fertility management in organic farming relies on a long-term integrated approach rather than the more short-term very targeted solutions common in conventional agriculture. 相似文献
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Watson EH 《Science (New York, N.Y.)》1934,79(2049):320-321
60.
Watson A 《Science (New York, N.Y.)》2000,290(5495):1287a-1288a
With calls to tie the European Space Agency (ESA) more closely to the business and security sectors (see sidebar), space scientists hope David Southwood, who will take over next May as ESA's science director, can nurture the agency's research with the skill he showed transforming its earth sciences division. Experts say he's up to the task. 相似文献