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During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.  相似文献   
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SUMMARY As part of a program to eradicate virulent footrot from Western Australia, 2745 isolates of Dichelobacter nodosus were isolated from 5263 specimens from 1883 submissions. The virulence of each isolate was assessed using protease thermostability and isoenzyme zymogram. We describe changes to the materials and methods required to handle these specimens and to reduce the interval between submission and report to 8 days.  相似文献   
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SUMMARY An aqueous suspension of air-dried, hammer-milled leaf of Terminalla oblongata (yellow-wood) was administered to sheep by gavage, as a single dose of 5 to 20 g (dry weight)/kg body weight. Doses of 15 g/kg, or more, caused depression, Inappetence, abdominal pain and reduced ruminal movements within 24 to 48 h and some sheep also showed dyspnoea, oplsthotonus and champing of the Jaws. Haematology and blood gas and acid-base measurements were unaffected. In sheep given a dose of 12.5 g/kg, or more, plasma osmolality, aspartate aminotransferase activity and potassium and bilirubin concentrations Increased while plasma total protein markedly decreased and plasma sodium concentration and alkaline phosphatase activity remained normal. Most sheep were necropsled 48 h after dosing. The liver showed zonal hepatocellular necrosis, the pattern of which varied with the dose given. No renal lesions were observed, although one sheep given a very high dose became azotaemic and hyperkalaemic. Hydrothorax, hydroperlcardlum and ascltes developed In sheep given doses of 15 or 20 g/kg.  相似文献   
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Epizootic ulcerative syndrome was diagnosed, and the presence of Aphanomyces invadans confirmed, from an outbreak of clinical disease in wild‐caught bony bream (Nematalosa erebi) from the Darling River near Bourke, in New South Wales, Australia, during 2008. This confirms a significant extension of the agent beyond its historical range.  相似文献   
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The objectives of this study were to determine the plasma and pulmonary disposition of gamithromycin in foals and to investigate the in vitro activity of the drug against Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) and Rhodococcus equi. A single dose of gamithromycin (6 mg/kg of body weight) was administered intramuscularly. Concentrations of gamithromycin in plasma, pulmonary epithelial lining fluid (PELF), bronchoalveolar lavage (BAL) cells, and blood neutrophils were determined using HPLC with tandem mass spectrometry detection. The minimum inhibitory concentration of gamithromycin required for growth inhibition of 90% of R. equi and S. zooepidemicus isolates (MIC(90)) was determined. Additionally, the activity of gamithromycin against intracellular R. equi was measured. Mean peak gamithromycin concentrations were significantly higher in blood neutrophils (8.35±1.77 μg/mL) and BAL cells (8.91±1.65 μg/mL) compared with PELF (2.15±2.78 μg/mL) and plasma (0.33±0.12 μg/mL). Mean terminal half-lives in neutrophils (78.6 h), BAL cells (70.3 h), and PELF (63.6 h) were significantly longer than those in plasma (39.1 h). The MIC(90) for S. zooepidemicus isolates was 0.125 μg/mL. The MIC of gamithromycin for macrolide-resistant R. equi isolates (MIC(90)=128 μg/mL) was significantly higher than that for macrolide-susceptible isolates (1.0 μg/mL). The activity of gamithromycin against intracellular R. equi was similar to that of azithromycin and erythromycin. Intramuscular administration of gamithromycin at a dosage of 6 mg/kg would maintain PELF concentrations above the MIC(90) for S. zooepidemicus and phagocytic cell concentrations above the MIC(90) for R. equi for approximately 7 days.  相似文献   
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OBJECTIVE: To identify risk factors associated with dysautonomia in dogs. DESIGN: Case-control study. ANIMALS: 42 dogs with dysautonomia examined between October 1988 and January 2000 and 132 control dogs examined during the same period for an unrelated problem. PROCEDURE: Information was gathered from medical records and surveys mailed to owners of case and control dogs. RESULTS: 42 case and 132 control dogs were included; completed surveys were returned by owners of 30 case and 103 control dogs. Dogs with dysautonomia were significantly younger (median, 18 months) than control dogs (median, 60 months) and more likely to come from rural areas and to spend > or =50% of their time outdoors. Compared with rural control dogs that spent at least some time outdoors, affected dogs were more likely to have access to pasture land, farm ponds, and cattle, and to have consumed wildlife, at least occasionally. The largest numbers of dogs with dysautonomia were identified during February and April, with relatively few dogs identified during the summer and early fall. CONCLUSION AND CLINICAL RELEVANCE: Although the cause of dysautonomia is unknown, results suggest that dogs with dysautonomia were significantly more likely to live in rural areas and spend > or =50% of their time outdoors than were control dogs examined for unrelated diseases.  相似文献   
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