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151.
The effect of single intraperitoneal 1 g.kg-1 doses of a solution of 20 amino acids (AA) on food intake was investigated in 20 piglets examined repeatedly between 2 and 26 days of age. The animals were reared individually from day 1 after birth in cages and bottle-fed a liquid diet nine times per day at two-hour intervals from 6 to 22 h. Although amino acid administration did not significantly affect plasma concentrations of total free AA throughout the experiment (as measured just before and 2 and 5 h after AA administration in blood withdrawn from the external jugular vein) it did produce a downward trend in food intake of piglets at 9-10 d of age. In older animals, the depressive effect on food intake was significantly greater and lasted longer. It is suggested that the aminostatic component of food intake regulation in piglets does not begin to operate until the weaning period. 相似文献
152.
153.
After a short irradiation at 366 nm with 200 lx, the intensity of conidiation ofTrichoderma viride colonies grown in the dark increased for the first 10 s proportionally with time. The increase slowed down after 10 s—6 min
of exposure and after 10–60 min of irradiation the conidiation intensity began to decrease. When photo-induced by daylight,
the conidiation started at a high rate after 25 h and persisted even after 48 h. The conidiation had no circadian character
and its periodicity depended on the periodicity of photo-induction. Its intensity was also influenced by the carbon sources
used, a maximum being reached with glucose (1–2 %). Higher glucose concentrations inhibited conidiation but had no influence
on growth of colonies. 相似文献
154.
As spontaneous abortion is a frequent finding in females with Factor XIII (FXIII) deficiency it has been presumed that this clotting factor is essential to normal pregnancy. FXIII subunit a (FXIII A) has been demonstrated in the homogenate of human uterus, but no information on its cellular distribution has been published, so far. In the present study first FXIII A was detected in paraformaldehyde-fixed, paraffin-embedded sections of human uterus by immunoperoxidase technique. Cells containing FXIII A were localized between collagen fibrils stained by Picrosirius Red F3B in the connective tissue. To characterize them the immunofluorescent detection of FXIII A was combined by the visualization of different marker antigens of monocytes and macrophages recognized by Leu-M3, RFD7, anti-HLA-DR and DAKO-anti-macrophage monoclonal antibodies on frozen sections. The coexpression of FXIII A with monocyte and macrophage differentiation marker antigens clearly proves that cells containing FXIII A in the uterus are monocyte-derived tissue macrophages. The results well agree with our previous findings demonstrating FXIII A in human monocytes and different types of macrophages. On the basis of these results, the presence of FXIII A does not seem to be a specificity of the uterus but a characteristic of monocyte/macrophage cell line including tissue macrophages, in general. 相似文献
155.
156.
The formation of two extracellular enzymes (α-amylase and a proteinase) ofB. subtilis was investigated in batch and continuous cultures. Differences were observed in the production of both enzymes in batch culture when studied in flasks and in a fermentor. The values of proteinase activity from continuous cultivation never reached those obtained during batch cultivation. The optimal dilution rate for proteinase synthesis was 0.1 – 0.2/h. The optimal dilution rate for the production of α-amylase was 0.2 –0.3/h. 相似文献
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