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31.
Secondary metabolites not only play important ecological roles in plants but also are important pharmaceutical and source compounds for derivative synthesis. Production of plant secondary metabolites is believed to be controlled by the endogenous signal network of plants. However, the molecular basis is still largely unknown. Here we show that matrine production of Sophora flavescens Ait. cells treated with low levels of jasmonic acid (JA) and nitric oxide (NO) is significantly increased although treatment with low concentrations of JA or NO alone has no effects on matrine production, showing that JA and NO may act synergistically in triggering matrine production. Moreover, treatment with NO triggers lipoxygenase (LOX) activity and enhances JA levels of the cells, showing that NO may activate the endogenous JA biosynthesis of S. flavescens cells. External application of JA induces nitric oxide synthase-like activities and stimulates NO generation of S. flavescens cells, which suggests that JA may trigger NO generation of the cells. Thus, the results reveal a mutually amplifying reaction between JA and NO in S. flavescens cells. Furthermore, JA and NO inhibitors suppress not only the mutually amplifying reaction between JA and NO but also the synergistic effects of NO and JA on matrine production. Therefore, the data demonstrate that the synergistic action of JA and NO in inducing matrine production might be due to the mutually amplifying reaction between JA and NO in the cells.  相似文献   
32.
Two experiments were performed to characterize the corticosteroid response of yellow perch Perca flavescens following an intraperitoneal injection of lipopolysaccharide (LPS) and determine if sustained differences in rearing density alter this response. In the first experiment, yellow perch were injected with LPS (3 mg kg−1), saline, or handled without receiving any injection. Concentrations of cortisol in plasma were elevated in all groups relative to non‐disturbed fish at 1·5 and 3 h after handling but by 6 h after injection the mean concentration of cortisol in plasma from LPS‐injected yellow perch were three to five times higher than fish before injection and significantly larger than groups of fish not treated with LPS. In the second test, yellow perch were held at different rearing densities (9 v . 18-19 kg m−3) for 3, 7 and 14 days before injection with LPS (3 mg kg−1). The cortisol response of yellow perch following LPS injection of fish held for 14 days at high density was significantly lower than that of fish held at the low density for the same duration. Additionally a trend of a decreased cortisol response to LPS injection as duration of holding increased was observed among fish held at high density relative to fish held at low density. These data illustrate that the corticosteroid response of yellow perch following LPS injection is distinct from handling alone and that the magnitude of the response is impacted by rearing density.  相似文献   
33.
苦参凝集素的分离纯化及部分性质研究   总被引:2,自引:0,他引:2  
从苦参 (SophoraflavescensAit.)根浸出液经硫酸铵分级 ,得苦参凝集素 (SFL)粗品 ,再经DEAE_Sepharose、SephadexG_1 5 0和HPLC层析 ,获得具有强凝集活性的SFL样品 ,用PAGE和SDS_PAGE检测均为单一蛋白染色带。SDS_PAGE显示SFL分子仅有一条肽链 ,SephadexG_1 0 0和SDS_PAGE测得其分子量均为 32kD。当SFL浓度为 0 .97μg/mL时能凝集兔红细胞 ,无血型专一性 ,其凝血活性可被甘露糖和果糖抑制 ,麦芽糖和葡萄糖有弱的抑制作用 ,凝集素分子含有 2 .89%的中性糖 ;当SFL量为 6 2 μg时 ,对棉花枯萎病菌 (FusariumvasinfectumAtk .)、小麦赤霉病菌(Gibberllasaubinetii (Mont.)Sacc .)和水稻稻瘟病菌 (PiriculariaoryzaeCav)菌丝体的生长发育有明显地抑制作用。用Edman法在蛋白测序仪上测出SFL的N端肽链 30个氨基酸的排列顺序为 :T/A/VDXLXFTFSDFDP NGEDLLFQGDAHVTSNN。  相似文献   
34.
苦参化学成分研究概况   总被引:19,自引:1,他引:19  
本文综述了苦参的药理、临床应用情况和苦参生物碱、黄酮等化学成分的结构特点及其结构测定方法.  相似文献   
35.
报道采自内蒙古和黑龙江的中国鳞伞属Pholiota新记录3种,即阿拉巴马鳞伞Pholiota alabamensis、变黄鳞伞Pholiota flavescens和暗黄鳞伞Pholiota pseudosiparia。研究标本存放在吉林农业大学菌物标本馆(HMJAU)。  相似文献   
36.
目的:将治糜灵栓剂(《中国药典》2010版一部)改为治糜灵凝胶剂,建立治糜灵凝胶剂的薄层色谱鉴别方法,为制定其质量控制标准制定依据。方法:参照《中国药典》2010版一部治糜灵栓剂项下黄柏、苦参、儿茶、冰片的薄层色谱鉴别方法,对处方中的主要药味进行定性鉴别。黄柏鉴别中以甲苯-乙酸乙酯-异丙醇-水(6:3:1.5:1.5)为展开剂;苦参鉴别中以甲苯-乙酸乙酯-甲醇(8:3:0.5)为展开剂;儿茶鉴别中以正丁醇-醋酸-水(3:2:1)为展开剂;冰片鉴别中以环己烷-三氯甲烷-乙酸乙酯(9:1:2)为展开剂。结果:薄层色谱上具有黄柏,苦参,儿茶,冰片的鉴别特征,且阴性对照无干扰。结论:色谱斑点清晰,专属性强;该方法操作简便,稳定性、重现性均很好。可作为质量标准的控制依据。证明治糜灵凝胶剂研究的方法可行。  相似文献   
37.
研究表明茶小绿叶蝉(Empoasca flavescens Fabricius)在云南大叶茶无性系良种云抗十号、云抗十四号、长叶白毫、矮丰上的生长发育历期、成活率、田间自然种群虫口数量、卵数量、卵分布等方面,皆有明显差异;说明这些品种对茶小绿叶蝉的抗性有差异,上述品种中矮丰对茶小绿叶蝉的抗性最强,云抗十号的抗性较差。在生产实践中对不同品种间存在的抗性差异应加以充分合理的利用。茶小绿叶蝉的空间分布型为随机分布型;在空间分布型方面,各品种间无明显差异。  相似文献   
38.
Abstract: The status of the specific name of the Southern sea lion is controversial; currently two names are in use: Otaria flavescens (Shaw, 1800) and Otaria byronia (de Blainville, 1820). The former was based on a two-foot-long yellowish otariid collected in the Strait of Magellan and the latter on a skull stated to have been collected on the Tinian Island (Marianas Archipelago); unfortunately both holotypes are lost. Otaria flavescens has date priority over Otaria byronia , but its identification was uncertain. This paper focuses on analyzing the main features of Shaw's holotype (body length, ear size, and hair color), which fit with the features of a Southern sea lion pup. As this was a tangible specimen from a valid locality and has priority over other available epithets, the specific name of the Southern sea lion should be Otaria flavescens (Shaw, 1800).  相似文献   
39.
The reaction distance of Gobiusculus flavescens to mobile and immobile copepod prey of different transparency was studied in water conditions with different turbidity levels or spectral composition. Both prey contrast (red or transparent Calanus spp.) and prey mobility caused reaction distance of G. flavescens to increase. The effect of prey mobility or prey transparency on reaction distance was independent of turbidity level. Longest reaction distances were measured for mobile and red prey at intermediate turbidity levels (10–20 JTU). Contrast threshold decreased with increasing turbidity. Although contrast of red and transparent copepod prey increased with increasing wavelength, longest reaction distances were observed at shorter wavelengths (blue–green). Lowest contrast threshold was found at shorter wavelengths. Visual pigments of G. flavescens are adapted to its natural environment. Both turbidity and spectral composition influenced G. flavescens contrast threshold.  相似文献   
40.
《Phytomedicine》2014,21(7):931-935
Matrine, a alkaloid of the root of Sophora flavescens, has multiple protective effects on the cardiovascular system including cardiac arrhythmias. However, the molecular and ionic mechanisms of matrine have not been well investigated. Our study aimed at to shed a light on the issue to investigate the antiarrhythmic effects of matrine by using ouabain to construct an arrhythmic model of cardiomyocytes. In this experiment, matrine significantly and dose-dependently increased the doses of ouabain required to induce cardiac arrhythmias and decreased the duration of arrhythmias in guinea pigs. In cardiomyocytes of guinea pigs, ouabain 10 μM prolonged action potential duration by 80% (p < 0.05) and increased L-type Ca2+ currents and Ca2+ transients induced by KCl (p < 0.05). Matrine 100 μM shortened the prolongation of APD and prevented the increase of L-type Ca2+ currents and Ca2+ transients induced by ouabain. Taken together, these findings provide the first evidence that matrine possessed arrhythmogenic effect of ouabain by inhibiting of L-type Ca2+ currents and Ca2+ overload in guinea pigs.  相似文献   
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