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The plasma levels, disposition kinetics and a dosage regimen for pralidoxime (2-PAM) were investigated in male buffalo calves following single intramuscular administration (15 or 30 mg/kg). The effects of 2-PAM on various blood enzymes were also determined. The absorption half-life, elimination half-life, apparent volume of distribution and total body clearance of 2-PAM were 1.08±0.19 h, 3.14–3.19 h, 0.83–1.01 L/kg and 184.9–252.1 ml/(kg h), respectively. At doses of 15 and 30 mg/kg body weight, a plasma concentration 4 g/ml was maintained for up to 4 and 6 h, respectively. Pralidoxime significantly lowered the serum level of transferases, phosphatases and lactate dehydrogenase but did not influence the acetylcholinesterase and carboxylesterase enzymes. The most appropriate dosage regimen for 2-PAM in the treatment of organophosphate toxicity in buffaloes would be 25 mg/kg followed by 22 mg/kg at 8 h intervals. 相似文献
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The disposition kinetics and urinary excretion of pefloxacin after a single intravenous administration of 5 mg/kg were investigated in crossbred calves and an appropriate dosage regimen was calculated. At 1 min after injection, the concentration of pefloxacin in the plasma was 18.95±0.892 g/ml, which declined to 0.13±0.02 g/ml at 10 h. The pefloxacin was rapidly distributed from the blood to the tissue compartment as shown by the high values for the initial distribution coefficient, (12.1±1.21 h–1) and the constant for the rate of transfer of drug from the central to the peripheral compartment, K
12 (8.49±0.99 h–1). The elimination half-life and volume of distribution were 2.21±0.111 h and 1.44±0.084 L/kg, respectively. The total body clearance (ClB) and the ratio of the drug present in the peripheral to that in the central compartment (P/C ratio) were 0.454±0.026 L/kg h) and 5.52±0.519, respectively. On the basis of the pharmacokinetic parameters obtained in the present study, an appropriate intravenous dosage regimen for pefloxacin in cattle for most of the bacteria sensitive to it would be 6.4 mg/kg repeated at 12 h intervals. 相似文献
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A non-ionic water-soluble galactomannan, having galactose and mannose in 1:6 molar ratio, was isolated from endosperm of the seeds of Ipomoea dasysperma. The seed mucilage was found to have a structure having a linear chain of beta (1-->4) linked mannopyranosyl units with D-galactose side chains attached through alpha (1-->6) linkage to the main chain. I. dasysperma seed gum possesses non-ionic characteristics of commercial seed gums and has potential to be used in food and pharmaceutical industries. 相似文献
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Megabase-scale mapping of the HLA gene complex by pulsed field gel electrophoresis 总被引:18,自引:0,他引:18
S K Lawrance C L Smith R Srivastava C R Cantor S M Weissman 《Science (New York, N.Y.)》1987,235(4794):1387-1390
In the study of the genetic structure of mammalian chromosomes, there exists a "resolution gap" between molecular cloning experiments and meiotic linkage analyses. This gap has discouraged attempts to construct full-scale genetic maps of mammalian chromosomes. The organization of the human major histocompatibility complex was examined within this range by pulsed field gel electrophoresis. The data obtained indicate that the complex spans over 3000 kilobases and enable the construction of a megabase-scale molecular map. These results indicate that the techniques employed in DNA extraction, enzymatic digestion, electrophoresis, and hybridization are suitable for the efficient analysis of megabase regions of mammalian chromosomes and effectively bridge the resolution gap between molecular cloning and classical genetics. 相似文献
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