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1.
测定了环丙沙星、氧氟沙星、单诺沙星、红霉素、罗红霉素、泰乐菌素、泰妙菌素、四环素等8种药物对羊肺炎支原体两个标准株Y-98和Y-goat的体外抑菌浓度以及红霉素与氧氟沙星、泰乐菌素对Y-goat和四环素与氧氟沙星、泰乐菌素对Y-98的联合药敏作用.结果表明,这8种抗菌药物对Y-goat和Y-98的MIC(μg/mL)分别为:环丙沙星0.223、0.002 23,氧氟沙星0.281、0.014 0,单诺沙星0.136、0.014 0,红霉素0.021 8、无效,罗红霉素0.032 7、无效,泰乐菌素0.042 2、0.039 0,泰妙菌素0.021 7、0.052 0,四环素0.195、0.052 0.红霉素与氧氟沙星的联合药敏指数为1,是相加作用;红霉素与泰乐菌素对Y-goat的联合药敏指数为1.5,是无关作用;四环素与氧氟沙星、泰乐菌素对Y-98的联合药敏试验指数均为0.375,是协同作用.  相似文献   
2.
Development of new semen cryopreservation techniques improving sperm survival and ensuring availability of viable spermatozoa for a prolonged time‐period after AI is promising tools to reduce sensitivity of timing of AI and enhance overall fertility. The SpermVital® technology utilizes immobilization of bull spermatozoa in a solid network of alginate gel prior to freezing, which will provide a gradual release of spermatozoa after AI. The objective of this study was to compare post‐thaw sperm quality and in vitro sperm survival over time of Norwegian Red bull semen processed by the SpermVital® (SV) technology, the first commercialized production line of SpermVital® (C) and by conventional procedure applying Biladyl® extender (B). Post‐thaw sperm motility was not significantly different between SV, C and B semen (p > .05). However, sperm viability and acrosome intactness were higher for SV than C and B semen (p < .05). Small differences in DNA quality were observed (p < .05). Sperm viability after storage in uterus ex vivo was higher for SV than for C semen (p < .05). Furthermore, sperm survival in vitro over time at physiological temperature was significantly higher for SV semen than C semen as well as B semen during the incubation period of 48 hr (p < .05). In conclusion, the SpermVital® technology is improved and is more efficient in conserving post‐thaw sperm quality and results in higher sperm viability over time in vitro for SV than for C and B semen.  相似文献   
3.
The effect of low dose dopamine on the excretory urographic image quality and contrast media-induced nephropathy in normal dogs (experiment 1) and the dogs with decreased renal function (experiment 2) were assessed. In experiment 2, decreased renal function was induced by gentamicin overdose. In each experiment, animals were divided into 3 groups. In group 1, only contrast medium (iohexol) was administered. In group 2, contrast medium plus intravenous fluid (0.9% saline) were administered. And in group 3, contrast medium plus intravenous fluid and low dose dopamine were administered. Investigated parameters included intrarenal resistive index (RI), serum BUN and creatinine concentrations, contrast medium elimination time and radiographic image quality. In experiment 1, RI of group I increased at 80 min after contrast medium administration (p<0.05), but RI of group 3 decreased at 48 and 72 hr (p<0.05). Serum BUN concentration of group 1 was higher than that of group 2 and 3 (p<0.05); in radiographic examination, contrast medium elimination time decreased in group 2 and 3, but image quality of group 2 was inferior to that of group 3. In experiment 2, image quality of group 3 only provided adequate visualization of renal structures. The formula of contrast medium plus low dose dopamine was found to provide good nephrogram and pyelogram image quality without supplemental contrast medium, and to protect renal tubules from prolonged exposure to concentrated contrast medium.  相似文献   
4.
A 7-year-old female Maltese presented for evaluation of severe vomiting. A diagnosis of pylorogastric intussusception was made during ultrasonographic examination. The intussusception spontaneously underwent reduction by the following morning.  相似文献   
5.
Some studies have shown that relative to baseline, the renal resistive index (RI) remains unchanged in nonobstructed kidneys and increases in obstructed kidneys after administration of furosemide. To our knowledge, the effect of mannitol administration on the renal RI of dogs has not been reported. We evaluated the renal RI in 16 kidneys in 8 young adult dogs after administration of mannitol. The mean RI decreased significantly from baseline (P < .01). Additionally, left complete ureteral obstruction wasinduced in 5 dogs. Evaluation by Doppler ultrasonography was performed for 5 days. On the 5th day, Doppler examination was repeated at 30 and 60 minutes after administration of mannitol to obstructed dogs. After induction of left ureteral obstruction, the RI of the left kidney increased significantly over 5 consecutive days. Administration of mannitol decreased the RI in the nonobstructed contralateral kidneys, and thus the RI difference between obstructed and nonobstructed kidneys was increased above normal (P < .001). In conclusion, administration of mannitol may be useful as another diuretic agent to identify unilateral ureteral obstruction on Doppler sonographic examination.  相似文献   
6.
A 10-year-old Maltese dog was presented with a firm mass on the left side of his neck. Physical examination confirmed a firm mass in the left and a submandibular swelling in the right cervical region. Sialolithiasis and associated sialocele in both mandibular salivary glands were suspected and bilateral sialoadenectomy was performed. The stones were identified as non-mineral sialoliths.  相似文献   
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A seven‐month‐old, entire, male miniature schnauzer dog was referred with acute vomiting, inappetence and depression primarily as a result of a gastric foreign body (pine cones). During investigations, thoracic radiographs revealed increased volume of the right lung lobes, deviated cardiomediastinal structures and elevation of the heart from the sternum. Thoracic computed tomography revealed left cranial lung lobe hypoplasia and extension of the right cranial lung parenchyma across the midline to the left hemithorax. Branches of the right pulmonary vessels and bronchi also crossed the midline and extended to the left caudal lung lobe. These findings suggested that the right and left lungs were fused. In humans this finding is consistent with horseshoe lung, which is an uncommon congenital malformation. To the authors’ knowledge, this case represents the first report of such a pulmonary anomaly in a dog.  相似文献   
10.
Comparative Earth History and Late Permian Mass Extinction   总被引:6,自引:0,他引:6  
The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction.  相似文献   
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