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91.
Abstract. Analyses of soil and hay samples collected from the Park Grass Experiment at Rothamsted during the last 137 years indicate slow but significant increases in KCl- and EDTA-extractable aluminium in soil and a sudden and very large recent increase in the concentration of aluminium in the herbage. The latter is associated with a sudden increase in the rate of acidification of the soil over the last 10–15 years and the mobilization of aluminium as the soil enters the aluminium buffer range -a Chemical Time Bomb. Such severe acidification from atmospheric inputs on a well-buffered soil illustrates how quickly an apparently stable situation can change as a result of acid deposition. It highlights the need to protect soils and plants from the effects of acidification by decreasing acid inputs or by liming. 相似文献
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D A Feeney G R Johnston J S Klausner V Perman J R Leininger M J Tomlinson 《Journal of the American Veterinary Medical Association》1987,190(8):1027-1034
A retrospective analysis was made of 30 cases of canine prostatic disease, with the objective of identifying (via a prepubic approach) the 2-dimensional, gray-scale ultrasonographic appearance most often associated with the various spontaneous prostatic diseases. Ultrasonography was of value in characterizing the parenchymal architecture as normal vs focally hyperechoic and diffusely hyperechoic (associated with chronic inflammation and neoplasia) or focally hypoechoic or anechoic (either accompanied by distant enhancement), which was associated with retention cyst or abscess. Further specificity based only on abnormal echotexture was not possible. Ultrasonography facilitated the differentiation of radiographically identifiable prostatomegaly attributable to abscess or neoplasia from apparent prostatomegaly attributable to paraprostatic cyst. An imaging protocol consisting of distention retrograde urethrocystography and prepubic ultrasonography was recommended, as a distended bladder aided ultrasonographic identification of the prostate gland. In addition, the combination of urethral morphologic features and urethroprostatic reflux appearance complemented the ultrasonographic appearance for differentiation of prostatic abscess from prostatic carcinoma. A classification scheme for spontaneous canine prostatic disease combining germane imaging morphologic features with microscopic and microbiologic findings was proposed. 相似文献
95.
Safety and immunogenicity of a vaccine bait containing ERA strain of attenuated rabies virus. 总被引:5,自引:5,他引:0 下载免费PDF全文
K F Lawson J G Black K M Charlton D H Johnston A J Rhodes 《Canadian journal of veterinary research》1987,51(4):460-464
Ninety percent of foxes fed commercial ERA vaccine in a specially designed bait developed rabies serum neutralizing antibodies. The vaccine bait did not cause clinical signs of rabies when consumed by foxes, raccoons, skunks, dogs, cats, cattle and monkeys. When presented, in the laboratory, to wild rodents of the species Microtus, Mus musculus and Peromyscus, the vaccine baits caused vaccine-induced rabies only in Mus musculus. Laboratory mice of the CD-1 and CLL strain were susceptible to vaccine-induced rabies; however, studies showed that transmission of virus to other animals did not occur. These studies suggest that the vaccine bait described could be useful in a rabies control program in areas where foxes and wild dogs are the principal vectors. 相似文献
96.
A probabilistic model was developed to estimate target and non-target avian mortality associated with the application of the avicide CPTH (3-chloro-p-toluidine hydrochloride) to minimize sprouting rice damage in the southern USA. CPTH exposures for individual birds were predicted by random sampling from species-specific non-parametric distributions of bait seed consumption and CPTH residues detected on individual bait seeds. Mortality was predicted from the species-specific exposure versus mortality relationship. Individual variations in this response were captured in the model by Monte Carlo sampling from species-specific distributions of slopes and median toxicity values (LD50) for each bird. The model was used to simultaneously predict mortality (percentage of exposed population and number of birds killed/weight of consumed bait) for a target (blackbird) and non-target (mourning dove) species feeding on bait sites for up to five consecutive days. 相似文献
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S.S. Sutherland D.V. Le Cras A.G. Robertson J.M. Johnston R.J. Evans 《Veterinary microbiology》1982,7(2):165-175
New and currently used serological procedures were evaluated using sera from cattle that were challenged with B. abortus S544 (S544) after vaccination with either B. abortus S19 (S19) or B. abortus 45/20 (S45/20) as calves or adults. In animals vaccinated with S19, titres to the indirect haemolysis test (IHLT) rose more slowly, declined more rapidly and involved fewer animals than did titres to the complement fixation test (CFT). In animals vaccinated with S45/20 the rough antigen complement fixation test (RCFT) showed persistent titres. At slaughter the IHLT and CFT were found to be more specific and more sensitive than the Rose Bengal Plate Test (RBPT) and Serum Agglutination Test (SAT) in the detection of cattle infected with B. abortus. 相似文献
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