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51.
Lipid composition of whole roots of wheat (Triticum vulgare Vill. cv. Svenno Spring Wheat) and oat (Avena sativa L. cv. Brighton) and of cell wall fractions, mitochondrial fractions and microsomal fractions of these roots were studied. Lipid composition depended upon the level of mineral nutrition. In wheat total phospholipids, phosphatidyl choline and sulfolipid content was highest in the roots grown at the higher salt concentration, while the reverse was true for oat roots. In both species glycolipid and sterol content was lower in the high salt roots, at the same time as higher proportions of them were built into the microsomal fraction. Phosphatidyl choline content of the wheat root membrane fractions increased with the salt level, while the opposite occurred in the oat roots. The phosphatidyl choline content may be correlated with the (Ca2+, Mg2+)-stimulated ATPase activity. 相似文献
52.
Zamani M Sharifi Tehrani A Ali Abadi AA 《Communications in agricultural and applied biological sciences》2007,72(4):773-777
The aim of this research was to determine if the attacks of green mold on orange could be reduced by edible salts alone or in combination with biocontrol agent. For this purpose toxicity to Pantoea digitatum and practical use of sodium carbonate (SC), sodium bicarbonate (SBC) and potassium carbonate, and potassium bicarbonate alone or in combination with antagonistic bacteria (Pseudomonas fluorescens isolate PN, Bacillus subtilis isolate VHN, Pantoea agglomerans isolate CA) to control green mold were determined. All were fungistatic. SC and SBC were equal and superior to the other salts for control of green mold on oranges inoculated 6h before treatment and were chosen for subsequent trails under cold storage conditions. The biocontrol agents were found completely tolerant to 3% sodium bicarbonate and sodium carbonate at room temperature; although their culturability was reduced by > 1000-fold after 60 min in 1% other salt solutions. Satisfactory results were also obtained with the combined treatment for control of green mold. A significant increase in biocontrol activity of all isolate was observed when combined with sodium carbonate and sodium bicarbonate. The treatments comprising CA combined with SB was as effective as fungicide treatment. Thus, use of sodium bicarbonate treatment at 3% followed by the antagonist P. agglomerans CA could be an alternative to chemical fungicides for control of green mold on oranges. 相似文献
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55.
Margulis A Bauer BS Alizadeh K 《Plastic and reconstructive surgery》2003,111(2):891-7; discussion 898
The recent fad of high ear piercing in the pinna has led to an increased incidence of auricular chondritis, which leads to dissolution of the cartilage and residual ear deformity. The typical postpiercing chondritis deformity presents as a structural collapse of the superior helical rim, scaphal cartilage, and the adjacent antihelix. The skin envelope is usually preserved, but it may be scarred from the infectious process and from previous drainage incisions. In the present article, the authors present a systematic approach to reconstruction of these acquired ear deformities. Careful assessment of the residual tissue is requisite to planning and appropriate reconstruction. The greater the cartilage loss, the more structural support is required to expand the skin envelope to its normal size and shape. The choice of cartilage donor site is made on the basis of the size of the defect and may include ipsilateral or contralateral conchal cartilage, bilateral conchal cartilage, or costal cartilage. Redraping of the carefully dissected skin and fixation of the flaps to the newly reconstructed cartilaginous framework usually provide sufficient soft-tissue coverage. A temporal-parietal fascial flap is preserved for the rare cases of extensive full-thickness skin loss or badly damaged and scarred auricular skin. 相似文献
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The intestinal mast cell response to Trichinella spiralis infection in mast cell-deficient w/wv mice
The intestinal mast cell response and lymphoblast activity, as measured by the incorporation of 3H-thymidine into mesenteric lymph node cells (MLN) of WBB6F1-w/wv(w/wv) mice, their normal congenic littermates (+/+) and C57BL/6J mice, were compared after infection with Trichinella spiralis. Marked and similar blast cell activity and an increase in number of cells were observed in the MLN of infected w/wv and C57BL/6J mice 7 and 15 days P.I. In contrast to C57BL/6J mice, primary T. spiralis intestinal infections were prolonged in w/wv mice and more muscle larvae were recovered from w/wv mice 29 days post-infection. In C57BL/6J mice mucosal mast cell (MMC) numbers increased on day 7 P.I. whereas in w/wv mice these cells did not increase significantly until day 15 post-infection, reaching a peak on day 22. In w/wv mice, the response to secondary infection as determined by an accelerated expulsion of adult worms did not occur until day 11 postchallenge whereas in +/+ and C57BL/6J mice worm expulsion was nearly complete at that time. In both primary and secondary infections, the MMC numbers in w/wv mice were significantly lower than in C57BL/6J or +/+ mice. The results suggest that prolongation of T. spiralis infection in w/wv mice is associated with delayed appearance of mast cells in the intestinal mucosa which may reflect slow generation of the intestinal inflammatory response. 相似文献
58.
Goldenkova I. V. Musiychuk K. A. Abdeev R. M. Berdichivets L. G. Alizadeh H. Piruzian E. S. 《Russian Journal of Plant Physiology》2002,49(3):364-368
The expression of the bacterial gene for thermostable -1,3-glucanase in transgenic tobacco plants was shown to induce substantial changes in plant morphogenetic potential, whereas the expression of -1,3; 1,4-glucanase did not affect essentially plant morphogenesis. Our results permit the suggestion that the expression of bacterial -1,3-glucanase in plants elevated the level of endogenous auxin. 相似文献
59.
Occurrence of arbuscular mycorrhizal fungi in saline soils of the Tabriz Plain of Iran in relation to some physical and chemical properties of soil 总被引:10,自引:0,他引:10
The abundance and distribution of arbuscular mycorrhizal fungi (AMF) were evaluated in the Tabriz Plain, where soil salinity levels range from 7.3 to 92.0 dS/m. Soil and root samples were collected from the rhizosphere of several glycophytes (Allium cepa L., Medicago sativa L., Triticum aestivum L. and Hordeum vulgare L.) and halophytes (Salicornia sp. and Salsola sp.) and were analysed for spore number in soil, root colonization with AMF and some physical and chemical soil properties. The number of AMF spores was not correlated significantly with soil salinity but suffered adverse effects from the accumulation of some anions and cations. Cluster analysis of correlation matrices showed that root colonization, soil pH, sand and clay percent, and soil-available P, rather than soil salinity and ion concentrations, were closely related with spore number. The percentage of root length colonized in glycophytes significantly decreased with increasing soil salinity. Barley roots showed 5% mycorrhizal colonization in high soil salinity (~20 dS/m). Halophyte roots were not mycorrhizal but more spores were found in rhizosphere than in non-rhizosphere soil. 相似文献
60.
Activation by Ca2+, Mg2+, Zn2+, or Mn2+ of adenosine triphosphatases in a microsomal fraction from wheat roots depends upon the growth temperature when the plants are grown under low salt conditions, but not when the plants get a full-strength culture medium. At low ionic strength, cultivation at 25°C gives only half as high activation as cultivation at 18°C or at high ionic strength at both temperatures. Corresponding data for activation of ATPases from oats also show that low ionic strength during growth gives the highest temperature dependence. Low temperature together with low salt conditions during growth gives the highest ATPase activity after stimulation with divalent cations. High growth temperature and full-strength medium decrease the ATPase activity. Activation energies (Ea) were calculated for the two temperature intervals 35–20°C and 20–5°C. The dominating ATPase stimulation (Ca2+ in wheat, Mg2+ in oats) is characterized by high specific activity combined with a low Ea value. The differences in ATPase activity between oats and wheat can be correlated with different cultivation requirements known from agriculture. 相似文献