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791.
Derek W. Cowling Andrew W. Bristow 《Journal of the science of food and agriculture》1979,30(4):354-360
An investigation was made of the S and N fractions and of the free amino acids in the shoots of perennial ryegrass (Lolium perenne L.) cv S23 grown in soil with and without added sulphate and in filtered air containing 0 and 400 μg SO2 m?3. Exposure to SO2 of potentially S-deficient plants alleviated the signs of deficiency; compared to deficient plants, the content of total and sulphate S was increased and the ratio N:S, as well as content of free amino acids, including asparagine and glutamine, was decreased. Similar exposure of plants grown with an adequate supply of S through the soil increased the content of sulphate but resulted in no significant alteration of the content of free amino acids. 相似文献
792.
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794.
The disinfecting effect of decametoxin, antibiotics, such as bensylpenicillin, streptomycin, monomycin and their combinations was studied on surgical threads of various thickness previously infected with Staph. aureus, Pr. vulgaris, Bac. anthracis, E. coli, Ps. aeruginosa and Bac. subtilis. It was shown that disinfection of the surgical silk with 0.1% solution of decametoxin for 15 minutes followed by its treatment with an antibiotic solution for 105 minutes provided absolute sterility. Treatment of the surgical silk with decametoxin and antibiotic combinations alone did not provide absolute destruction of the above test-microbes. It was found that treatment of the silk with 0.1% decametoxin solution for 24 hours did not decrease its strength. 相似文献
795.
In a study of pineal gland influences on hormone secretory profiles, blood samples were collected at 20 min intervals for 26 h from 4 pinealectomized and 4 sham-operated rams which were subjected to a 14.5 h daily photoperiod. Plasma levels of luteinizing hormone (LH) and testosterone (T) underwent rapid pulsatile fluctuations in all rams. Pinealectomized rams produced more LH than the sham-operated rams and a similar trend was recorded for plasma T data, since T secretion closely followed that of LH. A nocturnal elevation of plasma prolactin (Prl) levels displayed by sham-operated rams was substantially abolished by pinealectomy. Also a rise in cortisol secretion during the morning hours recorded from 3 of the sham-operated rams was absent in 2 of the pinealectomized rams. The possible significance of the pineal gland in the regulation of secretion of these hormones is discussed. 相似文献
796.