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101.
102.
A cat experimentally infected with feline immunodeficiency virus (FIV) but known to be free of feline leukaemia virus (FeLV) developed lymphosarcoma. The lesions in the liver and kidneys were present nine months after infection, when the cat was 21 months old. The cat had no overt signs of immunodeficiency and it is suggested that the B cell activation induced shortly after FIV infection produced a large pool of proliferating lymphocytes from which the malignant cells emerged.  相似文献   
103.
A preliminary investigation of the blood levels of carbenicillin, after the administration of a single intramuscular injection, suggests that the tortoise's bladder may act as a reservoir of antibiotic that is available for resorption. This phenomenon could confound the establishment of a safe, effective dose regime for antibiotics, in tortoises, which are excreted in an unchanged active form in urine.  相似文献   
104.
Diagnostic radiology of the esophagus, stomach, small and large intestine, mesentery, and pancreas is reviewed. Survey and contrast radiography remain the principal imaging methods used to evaluate gastrointestinal diseases in animals. Of the other imaging techniques, scintigraphy has potential in assessment of esophageal and gastric motility disorders, and detection of intestinal hemorrhage. Ultrasonography is useful for imaging the pancreas and gastrointestinal mass lesions.  相似文献   
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The objectives of this study were to compare the growth rates of normal thoroughbred foals to previously reported growth rates1 and to compare growth rates of normal foals with foals diagnosed with cervical vertebral malformation (CVM). Fifty-six foals from two foals crops were used, and eight of these foals were diagnosed with CVM. Growth rate analysis of the CVM foals had to be restricted to the period prior to diagnosis because once these foals were diagnosed, they were treated differently from the normal foals. Body measurements taken at 7 day intervals were body weight, wither height, hip height, and heart girth. For statistical analysis, data were broken down into 30 day intervals. Results showed that the growth rates for normal thoroughbred foals have not changed in the past fifteen years. The CVM foals tended to be heavier and taller during some time intervals than the normal foals, but there were no significant differences between the two groups in any of the skeletal growth measurements. Body weight gain was faster in CVM foals from 31–60 d (p<.01), 121–150 d (p<.01), and 211–240 d (P –.05).  相似文献   
108.
The gluteus medius muscles were removed from a four-year-old female Welsh pony and her nine-month-old fetus. The muscles were divided into sections which were histochemically examined to determine the variation in the distribution of fast-twitch-glycolytic (FG), fast-twitch oxidative glycolytic (FOG), and slow-twitch oxidative (SO) muscle fibers throughout the entire cross-section of the muscle. The fetal muscle had a larger percent of FOG fibers and smaller percent of SO fibers than the same muscle from the mare. Variation in the distribution of muscle fiber type within the fetal gluteus medius was found. This is the first study of fiber type variation in fetal equine muscle.  相似文献   
109.
Wind is an important vector in the dispersal of microorganisms to new habitats. However, wind dispersal is generally assumed to be random or logarithmically related to distance. We assessed the wind dispersal and subsequent establishment of an important group of plant symbionts, VA mycorrhizal fungi, across a 74 Ha recontoured surface mine. Winds were predominantly westerly aloft, but due to complex north-south ridges, up-valley, thermally-driven air flows developed. Patterns of spore dispersal were tested by a combination of released spore mimics from the potential source areas and by assessing the composition of species deposited across the site and in the putative source areas. Survival of the fungi was assessed two years after the dispersal patterns were monitored.The spore mimics moved in predictable but complex patterns across the site depending on the interactions of surface and upper winds. Mimics from the valley sources moved up the valleys in the lower flows and occasionally over the ridges in the upper winds. Those from the ridge approximately 2 km distant were entrained in the upper air flows and deposited all across the site. The VA mycorrhizal fungal species compositions from the soils correlated with the deposition patterns measured with the mimics.Fungal survival showed a pattern similar to dispersal; the fungi often survived in habitats not resembling the habitat of origin although some selection in both more favorable and less favorable sites occurred. These data suggest that microbial dispersal even by wind is predictable if the wind characteristics are known, that the VA mycorrhizal fungi from the site can survive in habitats different from their habitats of origin, but that some selection among species may occur after deposition.  相似文献   
110.
Five cases of gonitis in young cows are reported. In all cases lameness was severe with no weight bearing on the affected limbs. The joints were swollen. No organisms were isolated from the fluids aspirated from the joints but cytological examination showed large numbers of neutrophils, and biochemical analysis showed increases in the activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase.  相似文献   
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