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1.
The purpose of this study was to determine whether myocardial adenosine triphosphatase (ATPase) activities were reduced in pigs with naturally occurring hypertrophic cardiomyopathy (HCM). The selection of hearts for the HCM and the normal control groups depended on histological examination. Specific ATPase activity and 5-nucleotidase activity were measured in left ventricular myocardium obtained from HCM (n=7) and normal control (n=7) animals. The histological features of HCM included marked disorientation of muscle cells, thickening of the intramural coronary arterial wall with a narrowed lumen, endocardial fibrosis and myocardial fibrosis. The HCM group showed significant increases in both heart weight (32%) and heart weight to body weight ratio (46%). The total ATPase activity in crude homogenates from the HCM group was significantly decreased by 16%. Azide-sensitive ATPase (mitochondrial ATPase) activity, ouabain-sensitive ATPase (Na+,K+-ATPase) activity, basal Mg2+-ATPase activity and Ca2+-ATPase activity were all significantly decreased by 18%, 30%, 20% and 50%, respectively. In contrast, no significant decrease was found in the mean values for 5-nucleotidase activity. These results suggest that myocardial ATPase activities are suppressed in pigs with naturally occurring HCMAbbreviations ATP adenosine triphosphate - gww grams wet weight - HCM hypertrophic cardiomyopathy - Pi inorganic phosphate  相似文献   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
Deep-frozen semen from 28 bulls belonging to 6 different A.I. centres was studied after thawing and the ATP content in the spermatozoa was assayed using a bioluminescence technique. The sperm motility was subjectively estimated under a phase contrast microscope and the sperm concentration of each ejaculate was calculated in a haemocytometer. The overall mean ATP content was 16.6 nmoles ATP/spermatozoa x 10(8). There was a significant variation in ATP content between A.I. centres. Significant differences between bulls in ATP content were found as well as a significant correlation between ATP concentration and the number of motile spermatozoa. This may indicate that ATP assessment may be useful as an additional, objective laboratory test.  相似文献   
8.
It has been recognized that the cholinergic and adenosinergic systems have an essential role in immune and inflammatory responses during bacterial fish pathogens, such as the enzymes acetylcholinesterase (AChE) and adenosine deaminase (ADA), which are responsible for catalysis of the anti‐inflammatory molecules acetylcholine (ACh) and adenosine (Ado) respectively. Thus, the aim of this study was to investigate the involvement of the cholinergic and adenosinergic systems on the immune response and inflammatory process in gills of experimentally infected Rhamdia quelen with Streptococcus agalactiae. Acetylcholinesterase activity decreased, while ACh levels increased in gills of infected animals compared to uninfected animals. On the other hand, a significant increase in ADA activity with a concomitant decrease in Ado levels was observed in infected animals compared to uninfected animals. Based on this evidence, we concluded that infection by S. agalactiae in silver catfish alters the cholinergic and adenosinergic systems, suggesting the involvement of AChE and ADA activities on immune and inflammatory responses, regulating the ACh and Ado levels. In summary, the downregulation of AChE activity exerts an anti‐inflammatory profile in an attempt to reduce or prevent the tissue damage, while the upregulation of ADA activity exerts a pro‐inflammatory profile, contributing to disease pathophysiology.  相似文献   
9.
利用蝉花虫草Ophiocordyceps sobolifera代谢产物N6-(2-羟乙基)腺苷(HEA)作用于小菜蛾Plutella xylostella L.获得差异表达的片段,采用RT-PCR和RACE技术从小菜蛾中克隆全长1828 bp的小菜蛾腺苷受体(Plutella xylostella adenosine receptor,PxAdoR)基因,通过生物信息学软件预测和分析蛋白质结构,PxAdoR为分子量49.2 kD,没有信号肽,疏水性不稳定蛋白,具有7次跨膜螺旋结构的一类G蛋白偶联受体(G protein coupled receptor,GPCRs)。利用HEA及哺乳动物腺苷受体A2aR抑制剂SCH58261处理小菜蛾2龄幼虫,结果显示联合使用HEA和SCH58261后36~60 h,可使HEA引起的小菜蛾2龄幼虫的校正死亡率显著降低(42.7%~53.9%,P<0.05);而联合用药后36、48、60 h小菜蛾2龄幼虫体重增长抑制率由43.3%、38.3%、46.2%显著降低(P<0.05)到13.2%、10.3%、8.6%。本研究表明SCH58261能显著降低HEA引起的小菜蛾2龄幼虫的死亡率和体重增长抑制率,HEA可能是通过PxAdoR而起作用,PxAdoR基因可以作为新的杀虫靶点用于害虫控制研究。  相似文献   
10.
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   
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