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排序方式: 共有104条查询结果,搜索用时 78 毫秒
1.
This study analyzed the plasma lipid profile, glucose levels and fat deposits in male rats treated with aqueous extract of gross yerba mate, commercial yerba mate or water. Yerba mate treatment did not change body weight gain and lipid profile. The consumption of gross yerba mate significantly increased blood glucose (6.6 mmol/L) as compared to the water (4.8 mmol/L) and commercial group (5.2 mmol/L) and decreased epididymal and intra-abdominal deposits (10.1 mg/g and 23.7 mg/g of weight) as compared to the water (15.4 mg/g and 36.9 mg/g of weight) and commercial group (12.5 mg/g and 28 mg/g of weight). The results suggest that gross yerba mate reduces fat more efficiently but produces a greater increase in blood glucose when compared to commercial yerba mate and water groups.  相似文献   
2.
To investigate the effects of increased hydrostatic pressure on transmembrane signaling in deep-living marine species, the A1 adenosine receptor – inhibitory G protein (Gi) – adenylyl cyclase signaling complex was examined in brain membrane preparations from four teleost fish species of the deep-sea family Macrouridae. The combined depth ranges of the adults of these species, Coryphaenoides armatus, C. cinereus, C. filifer, C. pectoralis, span several hundred meters to 5400 m. Basal adenylyl cyclase activity, determined at 5 °C, was inhibited by increased hydrostatic pressure in all four species. At the highest pressure tested, 476 atm, adenylyl cyclase activity was inhibited 60 to 70% relative to the atmospheric pressure values. Pressure inhibition did not result from denaturation or loss of protein components from the membrane due to pressure-induced shedding. Despite the pressure-inhibition of basal adenylyl cyclase activity, the responsiveness of adenylyl cyclase activity to modulation by N6-cyclopentyladenosine, an A1 adenosine receptor agonist, was retained at elevated pressures. Because the accumulation of the second messenger cAMP depends on the summation of modulatory inputs, these results indicate that the transmembrane signaling in these deep-living species is insensitive to hydrostatic pressure changes.  相似文献   
3.
高效液相色谱法测定龙眼果实腺苷含量   总被引:2,自引:0,他引:2  
建立了测定龙眼果实腺苷含量的高效液相色谱(HPLC)法,并用此方法测定了5个龙眼品种果实不同部位的腺苷含量.色谱柱采用Phenomenex C18(4.6 mm×250 mm,5μm),流动相为甲醇和0.001 mol.L-1KH2PO4,梯度洗脱,流速1.0 mL.min-1,检测波长285 nm,柱温40℃.结果表明,腺苷含量为5-80μg.mL-1时,腺苷含量与峰面积呈良好的线性关系,相关系数为0.9999,平均回收率为98.01%,相对标准误为1.19%,最低检出限为0.013μg.mL-1.不同品种龙眼果实及果实不同部位的腺苷含量存在差异,假种皮含量最高,果皮次之,种子最低.所建立的方法简便、快速、灵敏、准确.  相似文献   
4.
建立了一种测定蜂花粉中腺苷含量的高效液相色谱法.样品经10%乙醇提取,过Waters OASIS柱固相萃取净化,液相色谱分离,257 nm波长处枪测,腺苷在1~100μg/mL范围内呈现良好的线性关系,R2=0.999 9,回收率较高,达到97%~101%,精密度好,相对标准偏差小于5%.该方法操作简单、准确、可靠.  相似文献   
5.
Previous experiments demonstrated that treatment of longan trees with potassium chlorate (KClO3) induces “off season floral induction” (FI) even in the absence of the naturally required cool temperature [Manochai, P., Sruamsiri, P., Wiriya-alongkorn, W., Naphrom, D., Hegele, M., Bangerth, F., 2005. Year around off season flower induction in longan (Dimocarpus longan, Lour.) trees by KClO3 applications: potentials and problems. Sci. Hortic. 104, 379–390]. Potassium chlorate, however, cannot replace the presence of functional mature leaves and sufficient light intensity. Here we examined in more detail the effect of shade (about 10% of natural sunlight) on KClO3 affected hormone concentrations/transport of leaves and shoot apical buds (SAB) and their interactions with FI.  相似文献   
6.
目的观察金黄色葡菌球菌(金葡菌)感染大鼠肺炎对肺动脉压力的影响,以及不同剂量腺苷对其调节作用。方法50只SD大鼠被随机分为对照组、肺炎组和腺苷处理A、B、C组。金葡菌经气管插管注入复制肺炎大鼠模型,实验第5天各腺苷处理组于心内肺动脉测压管内持续注射不同剂量的腺苷(50、100、150μg.kg-1.min-1),各腺苷处理组动态测定心率(HR)和平均肺动脉压(mPAP)。对照组、肺炎组同法注射等量的生理盐水,测定指标同前。处死大鼠取心肌组织作病理检测。结果(1)心肌病理组织检查示肺炎组病变明显,与对照组比较P<0.01;(2)肺炎组肺动脉压力较对照组增高[(2.67±0.38)vs(2.03±0.41),P<0.01)];(3)腺苷处理B、C组用药后平均肺动脉压均低于肺炎组(均P<0.05),而与对照组比较差异无统计学意义(P>0.05)。结论金葡菌感染大鼠肺炎可致肺动脉压力增高以及心肌损害,由肺动脉给以外源性腺苷可降低肺动脉压力。  相似文献   
7.
TLCS与HPLC对比测定虫草中虫草素和腺苷含量   总被引:3,自引:0,他引:3  
冬虫夏草[Cordyceps sinensis(Berk.)Sacc.]是资源十分紧缺的药用真菌,蛹虫草[Cordyceps militaris(L.Fr.)Link]是冬虫夏草的近缘种,也是虫草属的模式种[1],具有与冬虫夏草相似的活性成份和医疗保健功效,其主要活性成分虫草素和腺苷的含量,均高于冬虫夏草[2],是代替冬虫夏草的首选菌种.  相似文献   
8.
Antibody response to an antigen involves the co-operation between three types of cells: macrophages, T cells and B cells. The cognate interactions between these cells play a fundamental role in the expression of a specific antibody response, but the last is modulated by antigen-nonspecific soluble factors produced either by macrophages or by T cells. Macrophages elaborate a spectrum of molecules modulating the function of lymphoid cells; among them are IL1 and prostaglandins of the E series, which are respectively enhancer and inhibitor of the antibody response in vitro. These molecules alter T cell and B cell activities through different mechanisms involving activation or inhibition of IL2 production, or alteration of cells surface antigens. However, the cellular events following the fixation of soluble factor on its receptors are not known.  相似文献   
9.
农杆菌介导glgC-TM基因转化水稻研究   总被引:6,自引:1,他引:6  
 利用农杆菌介导将glgC-TM基因导入多个水稻品种。研究表明农杆菌转化过程中,潮霉素是一种很好的筛选剂,成熟胚以及国产的羧苄青霉素不适宜用作农杆菌介导的遗传转化。不同品种以及不同的质粒在转化过程中对抗性愈伤的得率和阳性植株的转化率不存在显著影响。T1代PCR检测表明,在转基因当代就有可能获得转基因纯系。  相似文献   
10.
目的:研究槲皮素单硫酸酯和5’-氨-5’-脱氧腺苷合用对凝血酶诱导兔血小板聚集的影响。方法:用比浊法检测血小板聚集。结果:槲皮素单硫酸酯和5’-氨-5’-脱氧腺苷对凝血酶诱导的兔血小板聚集都有抑制作用,两者合用作用增加。结论:槲皮素单硫酸酯与5’-氨-5’-脱氧腺苷具有协同抗血小板聚集的作用。  相似文献   
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