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51.
日本亮耳菌对植物病原真菌的拮抗试验   总被引:5,自引:0,他引:5  
 首次报道了日本亮耳真菌对植物病原真菌的拮抗活性.结果表明:除对竹荪疫霉(Phytophthora sp.)的拮抗方式是菌丝缠绕作用外,该菌株的菌丝体及其发酵液滤液对灰葡萄孢(Botrytis cinerea)、尖镰孢菌(Fusarium oxysporum)、绿色木霉(Trichoderma viride)、烟草疫霉(Phytophthora nicotianae)和稻瘟病菌(Pyricularia oryzae)均有很强的拮抗活性.  相似文献   
52.
疾病的治疗往往需要药物的联合使用,因此在用药过程中必须注意药物之间的相互作用,要充分发挥药物之间的协同治疗作用,尽可能减少药物的不良反应.本文对我院10025例门诊处方的用药进行了分析.  相似文献   
53.
西双版纳橡胶,咖啡和胡椒根际放线菌的抗菌作用研究   总被引:5,自引:0,他引:5  
对分别分离自橡胶、咖啡和胡椒根际的75-95株(8-11属)放线菌所作的拮抗测定表明,有拮抗作用的菌占44~46%,作为优势菌群一链霉菌有一半以上有抑菌作用。特别从三作物根际分离到对使柑桔、胡椒、辣椒三种作物致病疫霉菌(Phytophthora),咖啡炭疽(Colletatrichumlofteanum)和橡胶褐根病菌(Phellinusnoxius)分别有明显抑制作用的6株资源放线菌,有待开发研究。  相似文献   
54.
本文介绍了电子对抗中对混沌时间序列进行预测的一种数学模型和一种基于混沌序列的反侦察系统.指出了目前混沌技术在电子对抗中的应用状况以及电子对抗中的关键技术,对研究混沌技术及其应用有较重要的参考价值.文章还提出了在保密通信中应用时变系统的新设想,该设想在国内还没有实际使用.  相似文献   
55.
Sphingosine 1-phosphate (S1P) is an extensively studied signaling molecule that contributes to cell proliferation, survival, migration and other functions through binding to specific S1P receptors. The cycle of S1P1 internalization upon S1P binding and recycling to the cell surface when local S1P concentrations are low drives T cell trafficking. S1P1 modulators, such as fingolimod, disrupt this recycling by inducing persistent S1P1 internalization and receptor degradation, which results in blocked egress of T cells from the secondary lymphoid tissues. The approval of these compounds for the treatment of multiple sclerosis has placed the development of S1PR modulators in the focus of pharmacological research, mostly for autoimmune indications. Here, we report on a novel anellated bismorpholino derivative of oxy-fingolimod, named ST-2191, which exerts selective S1P1 agonist and functional antagonist potency. ST-2191 is also effective in reducing the lymphocyte number in mice, and this effect is not dependent on phosphorylation by sphingosine kinase 2 for activity. These data show that ST-2191 is a novel S1P1 modulator, but further experiments are needed to analyze the therapeutic impact of ST-2191 in animal models of autoimmune diseases.  相似文献   
56.
拮抗作用及传统医学的食物相克   总被引:5,自引:2,他引:3  
微量元素的生理活性取决于其化合物的溶解性,配位状态、浓度、溶液酸度以及其它元素浓度,拮抗作用的本质是元素的结构-性质-活性关系。其机理主要包括直接反应、形成MT的抑制反应,相似元素竞争配位部位以及社会、心理、遗传和个体易感性等,传统医学煌食物相克的实质还是物质的拮抗作用。  相似文献   
57.
The μ-opioid receptors belong to the family of G protein-coupled receptors (GPCRs), and their activation triggers a cascade of intracellular relays with the final effect of analgesia. Classical agonists of this receptor, such as morphine, are the main targets in the treatment of both acute and chronic pain. However, the dangerous side effects, such as respiratory depression or addiction, significantly limit their widespread use. The allosteric centers of the receptors exhibit large structural diversity within particular types and even subtypes. Currently, a considerable interest is aroused by the modulation of μ-opioid receptors. The application of such a technique may result in a reduction in the dose or even discontinuation of classical opiates, thus eliminating the side effects typical of this class of drugs. Our aim is to obtain a series of 1-aryl-5,6(1H)dioxo-2,3-dihydroimidazo[1,2-a]imidazole derivatives and provide more information about their activity and selectivity on OP3 (MOP, human mu opioid receptor). The study was based on an observation that some carbonyl derivatives of 1-aryl-2-aminoimidazoline cooperate strongly with morphine or DAMGO in sub-threshold doses, producing similar results to those of normal active doses. To elucidate the possible mechanism of such enhancement, we performed a few in vitro functional tests (involving cAMP and β-arrestin recruitment) and a radioligand binding assay on CHO-K1 cells with the expression of the OP3 receptor. One of the compounds had no orthosteric affinity or intrinsic activity, but inhibited the efficiency of DAMGO. These results allow to conclude that this compound is a negative allosteric modulator (NAM) of the human μ-opioid receptor.  相似文献   
58.
从发病魔芋植株中分离筛选获得拮抗菌株B J-1,通过抑菌试验和抗菌粗蛋白提取物的制备,对该菌的拮抗作用做了初步研究,发现菌株B J-1具广谱抗菌活性,对软腐病原菌有较强的抗菌作用.  相似文献   
59.
采用组织分离法从连翘枝条中筛选出13株内生菌,其中有7株内生真菌,6株内生细菌。分别以金黄色葡萄球菌、大肠杆菌为指示菌株,采用平板对峙法对分离出的13株内生菌的抗菌活性进行筛选。结果表明:13株菌种中有10个菌株对1种供试菌具有抑菌活性。其中L-07-01、L-07-09、L-07-12、L-07-13的拮抗效果明显,L-07-09对金黄色葡萄球菌具有较强的抑菌效果,测量其抑菌圈直径为10 mm。L-07-12对大肠杆菌具有较强抑菌效果,测量其抑菌圈直径为10 mm。对拮抗效果较强的菌株进行液体发酵培养后采用双层打孔法,测定其抑菌效果后证明L-07-13对金黄色葡萄球菌有极强的抑制效果。对拮抗后的指示菌进一步镜检后,发现菌体有明显的溶菌、空洞、畸形等现象。连翘内生菌可以产生丰富的具有药物活性的次生代谢产物,可作为新型药物的筛选源。  相似文献   
60.
Food innovation is moving rapidly and comprises new categories of food products and/or ingredients with a natural and ecological origin. Monocultivar olive pomaces, individually or combined, can be a source of natural bioactive compounds suitable for food or cosmetic applications. This work aimed to assess the phenolics content and antioxidant activity of four monocultivar olive pomaces (Arbosana, Koroneiki, Oliana, and Arbequina) and forty-nine blends prepared with different proportions of each. Additive, synergistic, and antagonistic effects were studied. Among the monocultivar pomaces, Koroneiki and Arbosana were the richest in total phenolics (~15 mg gallic acid eq./g). Most of the interactions found in the blends were additive or synergistic, while very few antagonistic effects were observed. The best results were obtained for those blends where the Koroneiki variety predominated: (i) 90% Koroneiki, 4.75% Oliana, 3.75% Arbequina, 1.5% Arbosana; (ii) 65% Koroneiki, 29% Oliana, 3.25% Arbequina, 2.75% Arbosana; and (iii) 85% Koroneiki, 8.75% Arbequina, 3.5% Arbosana, 2.75% Oliana. In sum, these combinations can be advantageous in comparison to the individual use of monocultivar pomaces, presenting a higher potential to be used as functional ingredients or for bioactive compounds extraction, having in view the obtention of natural preservatives or food/cosmetic formula enhancers.  相似文献   
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