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31.
In 2005, a prion disease identified in a goat from France was reported to be consistent with disease from the bovine spongiform encephalopathy (BSE) agent. Subsequent retrospective examination of UK goat scrapie cases led to the identification of one potentially similar, but as yet unconfirmed, case from Scotland. These findings strengthened concerns that small ruminant populations exposed to the BSE agent have become infected. The lack of data relating specifically to scrapie in goats has been contributory to past assumptions that, in general, sheep and goats respond similarly to prion infections. In this study, brain material from 22 archived caprine scrapie cases from the UK was reviewed by histopathology and by immunohistochemical examination for accumulations of disease-specific prion protein (PrP(Sc)) to provide additional data on the lesions of caprine scrapie and to identify any BSE-like features. The vacuolar change observed in the goats was characteristic of transmissible spongiform encephalopathies in general. PrP(Sc) immunohistochemical morphologic forms described in scrapie and experimental BSE infections of sheep were demonstrable in the goats, but these were generally more extensive and variable in PrP(Sc) accumulation. None of the cases examined showed a PrP(Sc) immunohistochemical pattern indicative of BSE.  相似文献   
32.
Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right lateral approach at the 16th rib resulted in resolution of intestinal protein loss and colic. The results of this case suggest that surgical resection of the ulcerated right dorsal colon may be the recommended treatment for right dorsal ulcerative colitis.  相似文献   
33.
A randomised sample of 2,809 apparently healthy sheep, 55 per cent of them less than 15 months of age, which were slaughtered for human consumption at abattoirs in Great Britain in 1997/98, was taken to establish the prevalence of scrapie infection. The medulla oblongata of each sheep was examined histopathologically at the level of the obex, and fresh brain tissue was examined for scrapie-associated fibrils (SAF) to establish whether there was evidence of scrapie. In addition, histological sections of the medulla from 500 of the sheep were immunostained with an antiserum to PrP, and the same technique was also applied to any animal found positive or inconclusive by the histological or SAF examinations. Any sheep which was positive by any of these diagnostic methods was also examined by Western immunoblotting, for the detection of the disease-specific protein PrP(Sc). A total of 2,798 sheep (99.6 per cent) were negative by all the methods applied. Ten animals were SAF-positive but negative by all the other methods, and in one animal there was immunohistochemical staining which could not be interpreted unequivocally as disease-specific. A mathematical model was used to estimate the prevalence of scrapie infection in the national slaughtered sheep population which would be consistent with these results. By this model, the absence of unequivocally substantiated cases of scrapie in the sample was consistent with a prevalence of infection in the slaughter population of up to 11 per cent.  相似文献   
34.
During 1972, 333 fluff samples were tested from 13 Queensland hatcheries and assessed according to the English standards for total count, coliforms and fungi. They were also assessed as being "standard" or "substandard", using a combination of the criteria of the English system. All hatcheries had at least 2 substandard samples and all the samples from 2 hatcheries were substandard.  相似文献   
35.
SUMMARY A group of 4 cows was vaccinated with Brucella abortus strain 19, followed 8 weeks later by a single dose of B. abortus 45/20 vaccine. A similar group received 2 doses of B. abortus 45/20 vaccine 8 weeks apart. The antibody responses of the groups were compared by testing whole serums and separated IgM and IgG fractions by the Rose Bengal Plate (RBP) agglutination and the complement fixation tests (CFT) using rough and smooth B. abortus antigens. Animals that had received B. abortus strain 19 responded to the 45/20 vaccine with increased titres to the smooth antigen. These relevant antibodies were predominantly of the IgG class. Standard CFT and RBP test antibodies could be detected in IgM and IgG fractions after the primary inoculation with B. abortus strain 19 vaccine.  相似文献   
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37.
On low cation exchange capacity, sandy soils where soil test Ca is low, potato tuber (Solanum tuberosum L.) Ca levels may not be optimal for maximum yield or quality; therefore, this study evaluated the effect of several levels of applied Ca on potato yield and quality on four soil types in Wisconsin. Calcium was applied to a Plainfield loamy sand, a Keiner loamy sand, a Pence sandy loam, and an Antigo silt loam at five rates in 1984 (0, 84, 252, 420, and 588 kg Ca ha?1) and at six rates in 1985 (0, 56, 112, 168, 224, and 336 kg Ca ha?1) as a band of CaSO4 in the hill. In 1984, on the Plainfield soil, three rates of sidedress Ca(NO3)2 (0, 84, and 168 kg Ca ha?1) were factorially combined with the five CaSO4 treatments to evaluate the efficacy of Ca(NO3)2 as a concomitant Ca and N source. In general, total yield was not affected by CaSO4 additions; however, the addition of approximately 100 kg Ca ha?1 as Ca(NO3)2 increased total yield 3.6 Mg ha?1. On the low-CEC, low-Ca soils (Plainfield and Kelner), improved tuber grade and/ or US1A size grade were detected with the addition of up to approximately 300 kg Ca ha?1 as CaSO4. The percent of US1A tubers increased 5 to 10% and the yield of US1A prime size (170–370 g) tubers increased 3.4 to 8.4 Mg ha?1 above control values. These improvements were accompanied by increased periderm Ca concentrations, even though leaflet Ca concentrations were not affected by Ca applications. The use of 100 kg Ca ha?1 asCa(NO3)2 in combination with CaSO4 was more effective than CaSO4 alone. On higher soil test Ca soils (Pence and Antigo), responses were inconsistent and periderm Ca was generally not increased.  相似文献   
38.
Fourteen millstream flours, a straight‐run flour, bran, pollard, and germ were prepared separately from two Australian and two New Zealand wheat cultivars using a 650 kg/hr pilot roller mill. Glutathione (GSH) and oxidized glutathione (GSSG) were measured in all samples. The Australian cultivars had higher levels of GSH and GSSG than the New Zealand cultivars, and in all cultivars the levels in pollard and germ were considerably higher than in flour samples. Generally, the early break flours and early reduction flours had lower GSSH/GSSG levels than the tail‐end break and reduction flours. There was a strong correlation between GSH/GSSG and ash content in millstream flours, which indicated that much of the GSH/GSSG in the flour was likely to have derived from contamination by bran, aleurone (pollard), and germ. There were also moderate to strong correlations between GSH/GSSG and the cysteine content of all proteins in flour. GSH/GSSG correlated strongly with the albumin and globulin content of flour but not with gliadin and glutenin. The volume and crumb texture properties of bread made with millstream flours in the absence of ascorbic acid (AA) were negatively correlated with GSH/GSSG. The change in bread volume and texture properties when AA was added to dough (baking improver effect of AA), however, were poorly correlated with GSH/GSSG.  相似文献   
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40.
The thermal diffusivity and conductivity of type C lunar samples returned by Apollo 11 are lower and less dependent on temperature than those of type A samples. The thermal properties of both types are lower than the corresponding properties of normal terrestrial rocks.  相似文献   
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