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The development of allergy in germ-free rats in chronic vibriocarriership was studied. The formation of specific delayed type hypersensitivity was found to occur to a limited extent in the animals devoid of normal microflora. The picture of hyperergic inflammation was revealed in the lymph nodes of vibriocarrier rats, the test for specific allergen being positive. 相似文献
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BOŽENA SKLÁRŠOVÁ PETER ŠIMON EMIL KOLEK PETER ŠIMKO ALENA BEDNÁRIKOVÁ 《Polycyclic Aromatic Compounds》2013,33(4):580-588
Benzo[a]pyrene (BaP) was dissolved in glyceryl trioctanoate, heated in a glass reaction vessel within temperature range 297.95–361.85 K with heating rate of 1 K/min and simultaneously exposed to UV light at wavelength λ = 365 nm at radiation power 20 mW cm?2 in order to study the decrease of BaP concentration due to its photooxidation. The concentration of BaP was determined by HPLC-FD periodically in 5 min intervals. As observed, the BaP concentration decreased from 62.2 μg L-1 to 19.8 μg L-1. From the experimental results, the parameters characterizing the non-isothermal kinetics of BaP photooxidation have been obtained. The parameters were tested at two various isothermal conditions (290.16 and 323.26 K) to verify a suitability of derived parameters. Comparing calculated and measured data of half-lives of BaP decrease at mentioned temperatures it was found that calculated half-lives are in a good accordance with those experimentally obtained values, when relative standard deviations at 290.16 K were 17.0% and 5.4% at 323.26 K, respectively. The kinetic parameters enable the calculation of the rate constant for any temperature in isothermal regime and make possible to model, in general, the kinetics of such processes without a deeper insight into their mechanisms. 相似文献