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81.
采用圆点印迹法检测GFkV,结果表明:Tris-HCl和PBS在提取GFkV时效果相同,在带毒葡萄植株中韧皮部的GFkV含量较高。 相似文献
82.
Wei Liu Duan-Wei Zhu Da-Hui Liu Wen-Bing Zhou Te-Wu Yang Ming-Jian Geng 《Journal of plant nutrition》2013,36(13):1905-1918
The effects of potassium (K) deficiency on primary and secondary metabolism in leaves of Chrysanthemum morifolium Ramat. were investigated in five different stages throughout the growing season of the plant to understand the relationship between potassium and the metabolism of C. morifolium. The results suggested that flavonoids content of K-deficient was related to 4-coumarate coenzyme A ligase (4CL) activity closely through the growth stage. Flavonoid and chlorogenic acid concentrations of K-deficient were lower than that of full K supply control (except flower bud differentiation period and budding stage in upper leaves), and the concentration in upper leaves was higher than that in bottom. The mechanism might be that the net photosynthetic rate was decreased in leaves of K1, which reduced the carbohydrate synthesized in leaves so that the coumarin concentration, which was the substrate of 4CL activity, decreased and consequently lead to the flavonoid and chlorogenic acid concentration decrease. 相似文献
83.
对虾传染性皮下与造血组织坏死病毒(IHHNV)的研究进展 总被引:2,自引:1,他引:2
为了研究对虾传染性皮下及造血组织坏死病的流行病学特点、检测方法及综合防治现状。笔者研究前人研究成果,对传染性皮下及造血组织坏死病毒的基本特性、感染宿主、传播条件、致病性、地理分布、基因组研究、检测技术及最新研究进展等方面的研究现状进行了综述。以期为对虾IHHNV的防控提供系统的参考资料。 相似文献
84.
猪繁殖与呼吸综合征是猪群中的一种免疫抑制性传染病,是严重危害养猪业的主要疫病之一,运用各种检测技术对该病做出准确的诊断是预防和控制该病的前提。猪繁殖与呼吸综合征的检测包括检测病毒、检测血清抗体及分型诊断,涉及的技术和方法有病毒分离技术、免疫组化技术、RT-PCR技术、间接免疫荧光试验、免疫过氧化物酶单层细胞试验、酶联免疫吸附试验、基因芯片技术等。每种诊断技术都有其各自的优势和局限性,应根据研究目的及工作条件等予以选择,作者对各种诊断技术的原理、方法及特点进行了概述和比较,并对今后的应用前景和发展趋势进行了展望。 相似文献
85.
Organic acids released into the rhizosphere may perform many beneficial functions to the plant including metal detoxification and enhancement of nutrient acquisition. Typically, these organic acids are studied in isolation; however, roots simultaneously exude a cocktail of organic acids and other substances, and their combined impact on rhizosphere processes may be quite different. It has been hypothesized that some exudates may play secondary roles (e.g. inhibitors of microbial activity, blockage of sorption sites), which might enhance the longevity and nutrient-mobilization capacity of others. Here we investigated how the decomposition, sorption and P-solubilizing effects of citrate, malate and oxalate are affected by the presence of malonate and shikimate. We found that in a range of agricultural soils the decomposition of citrate, malate and oxalate was rapid, but not influenced by the presence of large quantities of shikimate or malonate. This suggests that the individual organic acids are taken up by different transport mechanisms or components of the microbial community. At large concentrations, malonate decreased sorption of citrate, malate and oxalate on the soil, whilst shikimate had little effect. The capacity of citrate, malate and oxalate to desorb P was significantly greater in cocktails containing malonate compared with the single organic acid; no effect was seen with shikimate. We conclude that neither malonate nor shikimate at realistic concentrations will significantly affect the biodegradation of citrate, malate or oxalate in the rhizosphere, and while malonate did enhance P desorption, this effect is additive rather than synergistic. Overall, we found little evidence that malonate and shikimate act as secondary regulators of citrate, malate and oxalate behavior in soil. 相似文献
86.
本文证明培育牛黄对乙酰胆硷与氯化钡所引起的小白鼠离体小肠痉挛有解痉作用。培育牛黄的成份中去氧胆酸具有较强的抗乙酰胆硷与氯化钡作用,其浓度与效应呈直线相关。其成分中的胆酸仅有较弱的抗乙酰胆硷作用,且浓度与效应不呈直线相关,也无抗氯化钡作用。 相似文献
87.
The deterioration of two kinds of sandstone is discussed for two 18:th century buildings in central Stockholm: the Royal Palace, and the Royal Carolean Burial Chapel (Karolinska gravkoret) annexed to the mediaeval Riddarholm church. The facades of calcitic Gotland sandstone show many signs of serious decay, such as gypsum formation, pulverized surface, exfoliation, discolouration, and salt efflorescence. The socles are built of the more resistant quartzitic Roslagen sandstone, displaying some discolouration, cracks, and slight exfoliation. In total about 300 samples have been analysed. The surface concentration of sulphur is highest at ground level and at rain-sheltered positions. Chemical and sulphur isotope data indicate that the stone decay to a large part may be attributed to anthropogenic sources like acid deposition and car traffic. 相似文献
88.
[目的]探讨L-乳酸对湿木耳保鲜效果的影响,确定最优保鲜条件。[方法]以经处理的湿木耳在37℃下贮存7 d后细菌总数为试验指标,通过单因素试验,研究保鲜剂种类、L-乳酸浓度、灭菌温度和灭菌时间对湿木耳保鲜效果的影响。以L-乳酸浓度、灭菌温度和灭菌时间3个因素进行正交试验优选保鲜条件。[结果]双乙酸钠、山梨酸钾、L-乳酸3种保鲜剂对湿木耳均具有保鲜作用,其中以L-乳酸的保鲜效果最好,其保鲜效果随其浓度的升高而增强。正交试验表明,影响湿木耳保鲜效果的因素依次为:L-乳酸浓度〉灭菌温度〉灭菌时间;最适保鲜条件为:L-乳酸0.40%、灭菌温度80℃、灭菌时间4 min,此时细菌总数为950 cfu/g。[结论]L-乳酸完全能够对湿木耳进行合格、安全的保鲜。 相似文献
89.
90.