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Plasma and urinary levels of salicylic acid were examined in Standardbred mares after administration of various feeds, containing different compositions of hay. In addition, horses were administered acetylsalicylic acid orally and methyl salicylate topically. Elevated salicylic acid levels were observed in horse urine and plasma in animals fed lucerne hay. The plasma and urinary elimination of salicylic acid exhibited a diurnal pattern which was related to the type of feed and the feeding schedule. Within 24 h after oral administration of acetylsalicylic acid, plasma and urine salicylic acid levels were consistent with residual levels observed after feeding lucerne hay. Elimination of salicylic acid was rapid and complete, with a half-life between 5 and 7 h. Topical administration of methyl salicylate (8.4 g) produced elevated urinary salicylic acid levels for 6 h. A smaller dose of methyl salicylate (3.4 g) did not elevate plasma or urine salicylic acid levels above those observed following administration of lucerne hay.  相似文献   
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Three experiments were undertaken to determine the efficacy of different doses of buparvaquone in the infection and treatment immunization of cattle against Theileria parva derived from African buffalo (Syncerus caffer). Two of these experiments also compared buparvaquone with standard doses of long- and short-acting formulations of oxytetracycline. In addition, different dilutions of stabilates were used in the experiments. In the first experiment, a 10(-1.0) dilution of stabilate was used to infect groups of cattle treated with buparvaquone at doses of between 5 and 0.625 mg kg-1 body weight (bwt) on Day 0 after infection. All control cattle developed severe theileriosis and none of the treatment regimes (including those utilizing long-acting oxytetracycline) prevented the development of theileriosis. Treatment with buparvaquone at 2.5 mg kg-1 bwt or oxytetracycline gave the most satisfactory results. In the second experiment when the sporozoite dose was reduced to 10(-2.0) dilution, buparvaquone treatment at 5 and 2.5 mg kg-1 bwt and short- and long-acting formulations of oxytetracycline reduced reactions greatly. While all the oxytetracycline treated animals produced a serological response and were immune to a 50-fold higher challenge with the immunizing stabilate, several animals in the buparvaquone groups did not show a serological response and were not immune to challenge. In the third experiment, groups of cattle were infected with 10(-1.2), 10(-1.4) and 10(-1.6) dilutions of stabilate and were treated with 2.5 mg kg-1 bwt of buparvaquone. No animals developed severe theileriosis and all seroconverted. On homologous challenge, however, two out of 14 cattle showed severe reactions. It was concluded that further work on immunization using buparvaquone treatment at 2.5 mg kg-1 bwt and 10(-1.6) dilution of the stabilate would have to be carried out before such a system could be used in the field.  相似文献   
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Won J  Kim M  Yi YW  Kim YH  Jung N  Kim TK 《Science (New York, N.Y.)》2005,309(5731):121-125
Technologies to assess the molecular targets of biomolecules in living cells are lacking. We have developed a technology called magnetism-based interaction capture (MAGIC) that identifies molecular targets on the basis of induced movement of superparamagnetic nanoparticles inside living cells. Efficient intracellular uptake of superparamagnetic nanoparticles (coated with a small molecule of interest) was mediated by a transducible fusogenic peptide. These nanoprobes captured the small molecule's labeled target protein and were translocated in a direction specified by the magnetic field. Use of MAGIC in genome-wide expression screening identified multiple protein targets of a drug. MAGIC was also used to monitor signal-dependent modification and multiple interactions of proteins.  相似文献   
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