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211.
In our experience the camel (Camelus dromedarius) seems to be affected more commonly by dermoid cysts as compared to other cutaneous cysts. However, apart from one reference (Monteverde, 1935), the dermoid cyst has not been reported in the camel. This report documents dermoid cysts in identical locations in 11 camels with two camels having bilateral dermoid cysts at the similar site.  相似文献   
212.
In order to investigate usefulness of electrodiagnostic methods in Cauda Equina-Compression, 26 dogs with this disease were subjected to electromyography and spinal evoked potentials. 16 normal dogs served as controls. It was found that--after stimulation of the Nn.tibialis, peronaeus, pudendus and coccygeales and recording at the lumbosacral junction--latencies and nerve-conduction velocities were largely normal. However the amplitudes were decreased and--depending on the severity of the compression--the morphology of the potentials was altered although considerable standard deviations were obtained. Electromyographically, increased spontaneous activity with fibrillations and positive sharp waves were found in the myotomes of the lumbosacral nerves. Their number increased according to the severity of the cauda equina compression and they had a centrifugal distribution pattern. Based on these results it appears indicated to perform an electromyographic exam before applying myelography. The technique of spinal evoked potentials will need more refinement and standardisation before being useful in a clinical situation.  相似文献   
213.
The purpose of this study was to determine whether there were differences in skeletal muscle properties in the hindlimb muscles of different types of dogs. Muscle samples were obtained from the gracilis, sartorius cranial head, sartorius caudal head and tibialis anterior muscles of mixed-breed and hound-type dogs and Beagles. Fiber type, fiber size and capillary morphometry determinations of each muscle from each dog were made from sections stained for myofibrillar ATPase activity. Individual animals were bilaterally symmetric for all measured variables. Fiber type, fiber size and capillary geometry varied between dogs of a given type and muscles within a given dog. There were no differences between dog types for fiber type or fiber size; significant variation in log(muscle)/log(body) mass ratios between dog types was observed for all muscles. The results indicate that for a given muscle, significant variation can occur in skeletal muscle characteristics between different types of dogs and that these differences can be independent of differences in exercise history.  相似文献   
214.
Lymphoblastic lymphosarcoma with disseminated skeletal involvement was diagnosed in a 15-week-old Golden Retriever. The skeletal disease was characterized by diffuse, irregular areas of radiolucency most evident in the diaphyseal portion of long bones and was associated with gait abnormalities and signs of pain. Necropsy also revealed involvement of the spleen, liver, kidneys, and mesenteric lymph nodes.  相似文献   
215.
216.
This investigation was conducted to determine if Pasteurella haemolytica within feedlot cattle affected by pneumonic pasteurellosis express fimbriae (pili) and bacterial glycocalyx. Bacteriological culture of pulmonary tissue from three calves with fibrinous pneumonia resulted in heavy growth of P. haemolytica. Transmission electron microscopy of the lungs showed numerous microcolonies of gram-negative bacteria with morphology typical of Pasteurella haemolytica. The cells within these microcolonies possessed bacterial glycocalyces which stained with ruthenium red. Glycocalyx-encased microcolonies were also present in specimens examined by scanning electron microscopy. Typical P. haemolytica cells were evident in a tracheal specimen and these bacteria had radial glycocalyces consistent with polysaccharide and proteinaceous material condensed on linear structures suggestive of fimbriae. The pathogenetic importance of the bacterial glycocalyx and fimbriae in shipping fever pneumonia has yet to be established but their presence in clinical cases of Pasteurella pneumonia in feedlot cattle further supports a possible role in the initiation and progression of this disease as well as bacterial resistance to antimicrobial agents.  相似文献   
217.
Between September 1982 and March 1984, 101 Western Australian piggeries with 15 or more sows were surveyed to determine the prevalence of internal parasites and examine the relationship between parasitism and management practices. Faecal samples were collected from 20 pigs in 4 age groups in randomly selected piggeries, and examined for the presence of eggs of helminth parasites and protozoan cysts. Evidence of nematode parasites was found in 79% of piggeries. Sows were more commonly affected than other classes of pigs with worm eggs being found in 68% of herds. Oesophagostomum spp was the most prevalent worm species, being found in pigs from 65% of piggeries and in sows in 60% of herds. Ascaris suum was the most common species of worm found in growing pigs. There was no evidence of infection with either Metastrongylus spp or Strongyloides spp in any of the herds sampled. Oocysts of coccidia were found in pigs from 56% of piggeries and Balantidium coli cysts were detected in pigs from 42% of piggeries sampled.  相似文献   
218.
The effect of intravenous doses of cortisol and xylazine on the quantity of copper excreted in response to 100 and 200 mg doses of tetrathiomolybdate (TTM) was studied in seven sheep. Cortisol alone produced a non-significant 1.4-fold increase and had no enhancing action on the response to TTM. Xylazine produced a significant 2.25-fold increase, doubled the quantity of copper excreted in response to both doses of TTM and reduced bile flow by approximately 35 per cent. The alpha 2 antagonist, idazoxan, prevented both the latter effects showing that they were due to xylazine's alpha 2-agonistic action. It is suggested that the combination of an alpha 2-agonist with the intravenous injection of TTM in the treatment of acute copper toxicity in sheep could reduced by 50 per cent the amount of molybdenum needed.  相似文献   
219.
The ability of Mycoplasma hyopneumoniae to agglutinate RBC was evaluated to develop an in vitro cytadsorption assay. Using swine RBC in a microtitration hemagglutination test, no agglutination or partial agglutination was detected. Comparison of RBC from various other species indicated that improved hemagglutination was obtained with RBC from turkeys. This hemagglutination was detected only when mycoplasma cells used in the assay had been frozen and thawed, heated at 50 C for 30 minutes, or treated with trypsin. Treatment of RBC with trypsin or neuraminidase enhanced hemagglutination. Possible surface lectin activity in M hyopneumoniae was evaluated by use of carbohydrates in a blocking assay; hemagglutination was not inhibited by any of 13 carbohydrates evaluated. Mycoplasma hyopneumoniae convalescent porcine serum and monoclonal antibodies against 2 M hyopneumoniae immunogens of molecular weights of 64,000 and 41,000 inhibited hemagglutination.  相似文献   
220.
Resistance of gram-negative bacteria to gentamicin has become an increasingly common problem among clinical isolates from human beings. Susceptibility of isolates from horses to gentamicin and amikacin was evaluated for the period from July, 1983 to June, 1985. All isolates of Escherichia coli, and species of Enterobacter, Klebsiella, Proteus, and Pseudomonas examined were susceptible to amikacin, except 2 of the 46 Pseudomonas isolates. In contrast, 13 to 50% of isolates were resistant to gentamicin. Escherichia coli, and Klebsiella, Proteus, and Enterobacter species isolates were highly significantly more susceptible to amikacin (P less than 0.01) than to gentamicin. Pseudomonas spp (P = 0.13) were not significantly different in susceptibility to the 2 drugs. There was significant variation among genera in their susceptibility to gentamicin (P = 0.002), primarily because of the frequency of resistance in isolates of Klebsiella spp and Proteus spp, compared with the other 3 organisms (E coli, Enterobacter spp, and Pseudomonas spp). There was no significant difference of susceptibility to amikacin among the genera studied (P = 0.06).  相似文献   
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