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961.
Albendazole administered to cattle at doses of 45, 35, 25, and 15 mg/kg of body weight reduced the number of viable Fasciola hepatica adults by 99.8%, 97.6%, 97.6%, and 95.7%, F hepatica immatures by 100%, 98.6%, 98.6% and 91.9% and Fascioloides magna by 96.5%, 99.1%, 94.0%, and 94.0%, respectively. Statistical evaluation by one-way analysis of variance, showed significant (P less than 0.05) differences in burdens of each fluke species between treated and untreated cattle, but differences in efficacy between any two of the four drug doses were not significant. Signs of toxicosis were not observed between the time of drug administration and slaughter 7 to 10 days later. 相似文献
962.
Sulfamethazine residues in uncooked edible tissues of port following recommended oral administration and withdrawal. 总被引:1,自引:0,他引:1
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Commercial feed rations containing sulfamethazine at the level of 110 ppm were fed for a period of 65 days to market pigs in a study simulating normal farm practices. The levels of sulfamethazine at the end of medication were in excess of 10 ppm in liver and kidney and up to 2.6 ppm in muscle tissues. Concentrations of sulfamethazine in tissues from pigs after withdrawal of medicated feed depleted to 0.1 ppm within nine days. The rate of depletion was similar for all tissues. It was observed that storage of tissue samples at freezer temperature (-20 degrees C) for 30 days further reduces sulfamethazine levels by 3 to 20% of their original value. 相似文献
963.
Applications of GA3 in May/June, when the first flush of growth was maturing, induced an extra flush of vegetative growth and initiated lateral bud break. Flower initiation was delayed and flower size reduced by the GA3. These responses were only slightly modified by additional sprays with BAP and TIBA. GA4+7 was ineffective in promoting either extra extension growth or lateral bud break, but it did reduce flower size. 相似文献
964.
965.
Benlate (50 per cent wettable powder), the commercial formulation of the systemic fungicide benomyl, was applied to a flooded alluvial soil at concentrations of 5 to 100 μg/g active ingredient. At about the field application rate (S μg/g), benomyl retarded the decrease in the redox potentials of the flooded soil and curtailed the accumulation of iron and manganese in solution, both without and with added rice straw (0.5 per cent). 相似文献
966.
967.
T.N. Patil J.N. Telford F.W. Plapp R.B. Koch 《Pesticide biochemistry and physiology》1979,12(1):95-104
A water-soluble Mg2+-dependent ATPase (coupling factor F1) was isolated from the mitochondria of housefly thorax. It comprised about 14% of the proteins from a crude preparation. The F1 preparation was nearly homogeneous as assessed by gel electrophoresis, isoelectric focusing, and electron microscopy. It was composed of five subunits with the following apparent molecular weights: α, 68,000; β, 61,000; γ, 38,000; δ, 27,000; and ?, 17,500. The isoelectric pH (pI) of this protein was 7.3. F1 had a pH optimum of 8.2 and a temperature optimum between 37 and 45°C. The enzyme was fairly stable at 25°C. Nearly complete loss of activity was noticed at 0°C, while at 0 or 25°C, glycerol (20%) partially stabilized the enzyme activity against such inactivation. The Km value of the enzyme with respect to ATP was 0.4 mM. The activity was stimulated by low concentrations of 2,4-dinitrophenol. The enzyme was inhibited by azide, p-hydroxymercuribenzoate, and guanidine hydrochloride. Oligomycin and the pesticides pyrethrin, cyhexatin, and DDT have no effect on the enzyme activity. However, all of these chemicals inhibited intact Mg2+- ATPase. The results are discussed in the light of differential responses of soluble and intact ATPase to these pesticides. 相似文献
968.
969.
970.