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从顶质体的发现、起源、形态学、基因组以及生物学功能等方面介绍了顶复门寄生虫顶质体的一些研究进展,说明了顶质体对于顶复门寄生虫的存活具有十分重要的作用,它参与了脂肪酸、血红素以及类异戊二烯的生物学合成。提示,顶质体所具有的新陈代谢功能也使其成为研制抗寄生虫药的潜在靶位点。 相似文献
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Cornelisse CJ Robinson NE Berney CE Kobe CA Boruta DT Derksen FJ 《Equine veterinary journal》2004,36(5):426-430
REASONS FOR PERFORMING STUDY: Although the efficacy of dexamethasone for the treatment of recurrent airway obstruction (RAO) has been documented, the speed of onset of effect and duration of action are unknown, as is the efficacy of orally administered dexamethasone with or without fasting. OBJECTIVES: To document the time of onset of effect and duration of action of a dexamethasone solution i.v. or orally with and without fasting. METHODS: Protocol 1 used 8 RAO-affected horses with airway obstruction in a crossover design experiment that compared the effect of i.v. saline and dexamethasone (0.1 mg/kg bwt) on pulmonary function over 4 h. Protocol 2 used 6 similar horses to compare, in a crossover design, the effects of dexamethasone i.v. (0.1 mg/kg bwt), dexamethasone per os (0.164 mg/kg bwt) with and without prior fasting, and dexamethasone per os (0.082 mg/kg) with fasting. RESULTS: Dexamethasone i.v. caused significant improvement in lung function within 2 h with a peak effect at 4-6 h. Dexamethasone per os was effective within 6 h with peak effect at 24 h at a dose of 0.164 mg/kg bwt prior to feeding. The duration of effect was, for all dexamethasone treatments, statistically significant for 30 h when compared to saline and tended to have a longer duration of effect when used orally. Dexamethasone per os at a dose of 0.164 mg/kg bwt to fed horses had mean effects comparable to dexamethasone at a dose of 0.082 mg/kg bwt per os given to fasted horses, indicating that feeding decreases bioavailability. CONCLUSIONS: Dexamethasone administered i.v. has a rapid onset of action in RAO-affected horses. Oral administration of a bioequivalent dose of the same solution to fasted horses is as effective as i.v. administration and tends to have longer duration of action. Fasting horses before oral administration of dexamethasone improves the efficacy of treatment. POTENTIAL RELEVANCE: Oral administration to fasted horses of a dexamethasone solution intended for i.v. use provides an effective treatment for RAO-affected animals. 相似文献
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Borlaug NE 《Science (New York, N.Y.)》2004,303(5661):1137-1138
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Houston DM Rinkardt NE Hilton J 《Veterinary therapeutics : research in applied veterinary medicine》2004,5(3):187-201
Clinical signs of struvite urolithiasis resolved in an average of 19 days in cats fed either a canned or dry urine-acidifying, magnesium-restricted diet, and stones completely dissolved in 31 of 39 cats in an average of 30 days. Stones were surgically removed from five cats, and analysis revealed that these stones were not composed of struvite. The results of this study strongly suggest that the diet will dissolve naturally occurring feline struvite bladder uroliths. 相似文献