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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
121.
Rothblatt S 《Science (New York, N.Y.)》1986,232(4753):1013-1014
122.
Walt SM 《Science (New York, N.Y.)》1986,232(4753):1014-1015
123.
Ten out of eleven subcutaneous abscesses in cats harboured anaerobic bacteria. Seven of the ten abscesses contained a mixture of obligate anaerobes and facultative anaerobes or microaerophilic bacteria. All of the anaerobic isolates were sensitive to the antibiotic metronidazole, but were resistant to streptomycin. Three isolates from one abscess were resistant to penicillin and ampicillin. Clinical resolution of subcutaneous abscesses was poor when procaine penicillin was used alone as treatment. 相似文献
124.
Field treatments in a vineyard with 0.015 or 0.01% a.i. of cypermethrin, fenvalerate, fenpropathrin or AC-222,705 were more efficient in controlling the grape-berry moth (Lobesia botrana Schiff.) and the honeydew moth (Cryptoblabes gnidiella Mill.) than four standard treatments consisting of two with 0.05% a.i. fenitrothion and two with 0.075% a.i. diazinon. In pyrethroid-treated plots, infestation at the end of the trials ranged between 2.5 and 12%, compared with 21% in the standard treatment plots and 34% in the untreated plots. Cypermethrin, fenpropathrin and AC-222,705 exhibited similar field activity, while that of fenvalerate was somewhat lower. Under laboratory conditions, cypermethrin at 0.005 and 0.01% a.i. was significantly more potent than fenvalerate, fenpropathrin and AC-222,705; at a higher concentration, 0.015% a.i., all pyrethroids were highly active, with mortality ranging between 75 and 95%. Under laboratory conditions the vinegar fly (Drosophila melanogaster Meig.) was in general more susceptible to pyrethroids than was the grape-berry moth. Cypermethrin and AC-222,705 at 0.005% a.i. and avermectin at 0.0035% a.i. were potent compounds against the vinegar fly and more active than fenvalerate and fenpropathrin. 相似文献
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126.
G. I. McINTYRK 《Weed Research》1962,2(3):165-176
Summary. Previous findings suggested that the translocation in Agropyron repens of 2,2-dichloropropionic acid (dalapon) may be considerably affected by the transpiration rate. This relationship has been studied further in the present investigation using 14 C-labelled material and autoradiography.
It was found that when dalapon was applied to the leaves and the treated plants were placed in darkness a reduction in the transpiration rate of ca. 90% was associated with a marked increase in the amount of dalapon translocation into the roots and tillers. The evidence provided by the autoradiographs was confirmed by a quantitative assay of the14 C present in the roots. It was also found, however, that translocation was not appreciably affected either by a 50% reduction in the light intensity or when the transpiration rate was reduced by placing the plaints under conditions of high humidity in the light or by the application of white petroleum jelly to the leaves. An alternative hypothesis, namely that the effect of darkness on the movement of the herbicide might be due to changes induced in the normal pattern of assimilate translocation was also investigated but was not supported by the results obtained. Further experimentss, in which various parts of the treated shoot were placed in the dark, suggested that the effect of darkness on the translocation of dalapon is exerted primarily on the treated leaf itself.
Etudes sur to migration dans Agropyron repens de l'acide 2,2-dichloropropionique marqué avec14 C 相似文献
It was found that when dalapon was applied to the leaves and the treated plants were placed in darkness a reduction in the transpiration rate of ca. 90% was associated with a marked increase in the amount of dalapon translocation into the roots and tillers. The evidence provided by the autoradiographs was confirmed by a quantitative assay of the
Etudes sur to migration dans Agropyron repens de l'acide 2,2-dichloropropionique marqué avec
127.
I M Skurikhin 《Journal of the Association of Official Analytical Chemists》1989,72(2):294-297
To evaluate the suitability of the analytical methods used in determining food safety, a new metrological characteristic "MQS" is suggested. MQS is defined as the absolute minimum quantity in micrograms of a substance that can be determined in a test solution (solubilized test portion). MQS accounts for 2 factors: (a) the necessity for a reliable determination of ML (maximum permitted level, i.e., regulatory tolerance), and (b) the optimum quantity of test portion of a food product to be analyzed, and thus assists in evaluating the suitability of a method to assure food safety. The MQS of 8 toxic elements in any food are As, 3; Cd, 0.5; Cu, 20; Fe, 50; Hg, 0.2; Pb, 4; Sn, 200; Zn, 100 micrograms. To characterize the applicability of any given method, the specific minimum limit of determination, MQSM, must be established for each method. The method in question may be used to control food safety only if MQSM is less than MQS. MQSM values are given for the common polarographic and colorimetric methods for determining these elements. 相似文献
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