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101.
A 2.5 year old Appaloosa stallion with progressive weight loss and a heart murmur was diagnosed as having vegetative endocarditis of the right atrioventricular valves with a mass in the right atrium. The ultrasonographic appearance of the lesion was characterized by extreme reverberation. On postmortem examination, a 9 cm diameter thrombus was found within the right atrium and auricle, occupying approximately 80% of the chamber volume. Additionally, a lenticular abscess extended throughout the parietal cusp of the right atrioventricular valve. Histologic examination revealed that the lesions were septic with numerous gram positive cocci in short chains, suggestive of Streptococcus equi , and gram negative rods.  相似文献   
102.
An apocrine adenocarcinoma was observed in the subcutis of the abdomen of golden hamster. Histologically, the tumor cells irregularly formed multiple layers of cysts and some detached cells were presented in the cystic space. PAS stain with alpha-amylase digestion revealed PAS-positive alpha-amylase-resistant granules in the cytoplasm. Immunohistochemically, cytokeratin was demonstrated in the tumor cells. By electron microscopy, the tumor cells had an oval nucleus with invagination, abundant cytoplasmic organelles and microvilli protruding into the intercellular spaces.  相似文献   
103.
Six bullmastiffs with congenital heart disease were evaluated over a three-year period. In all the cases the problem was shown to be dysplasia of the pulmonary valve. Five cases were male, one was female. All dogs available to follow-up developed signs of cardiac decompensation. Bullmastiffs must be added to the list of breeds in which valvular pulmonic stenosis is encountered frequently.  相似文献   
104.
Abstract. Leaching losses of nitrate-nitrogen were measured from a set of eight hydrologically isolated plots on a clay loam soil over the period from September 1987 to February 1990. Variable drainflow recovery from the plots hampered accurate estimation of nitrate loading, but results suggest that, when inorganic nitrogen fertilizer is applied up to the recommended amount, there is little influence of the amount applied on the amount leached. We did, however, observe the following effects on nitrate leaching: leguminous green manure incorporated in autumn increased leaching of nitrate-nitrogen by 10–15 kg per hectare during the winter; autumn cultivation caused some increase in leaching compared with no cultivation in one year; some systematic variations in nitrate leaching occurred between years and between plots, but were unrelated to treatments.
From the results we conclude that green manuring does not provide sufficient nitrogen for organically grown crops on this soil but contributes significantly to nitrate leaching, and that growing spring cereals, with the land remaining in stubble as long as possible in autumn, may be the best strategy to minimize nitrate leaching.  相似文献   
105.
Contents: An insemination trial using frozen semen is described. The freezing procedure was slightly modified from the Hannover method. The insemination dose consisted of 7 medium straws containing approx 1 109 spermatozoa. A total of 28 mares of the Norwegian Trotter breed were inseminated during the 1991 season. During oestrus the mares were examined at 12 hour intervals, and the insemination was carried out after detection of ovulation. The pregnancy rate was 43% after the first insemination, increased to 68% after second and further to 75% after the third and last insemination. The foaling rate was 61.5%.  相似文献   
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This report describes the use of 99mtechnetium pertechnetate (99mTcO4) and 131[for imaging of a metastatic thyroid carcinoma in a dog. The 131] imaging showed metastatic lesions undetected by the 99mTcO4 imaging on 2 separate occasions. The possible mechanisms for the discrepancies between 131I and 99mTcO4 imaging of thyroid carcinomas are discussed. The use of 131I for the imaging of functional thyroid carcinomas in the dog is recommended.  相似文献   
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Time course of grain filling pattern in two rice (Oryza sativa L.) cultivars, grown under normal and low light intensities, was studied. The number of spikelets, partially filled grains and high density grains were monitored at a 5 day interval during grain filling period from uniform panicles tagged at anthesis. The low light tolerant cultivar Swarnaprabha had more high density grains and less partially filled grains throughout the grain filling period and at harvest compared to cultivar Ratna under both normal and low light intensities. Further, the opening of spikelets in two flushes in Swarnaprabha seemed to result in a more efficient resource allocation and hence better yield as compared to Ratna, in which the opening of spikelets was in a single flush on day 10.  相似文献   
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