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排序方式: 共有172条查询结果,搜索用时 15 毫秒
1.
目的:外泌体及其内容物是各种肝脏疾病的潜在生物标志物。本研究探索外泌体及其内容物在肝移植排斥反应及预后中的作用。创新点:本研究发现外泌体及内含物半乳糖凝集素-9(galectin-9)在肝移植术后排斥及预后预测中发挥重要作用。方法:分别从急性排斥和肝功能稳定患者提取外泌体,进行分离、鉴定并检测其内含蛋白。候选蛋白通过在73个急性排斥病人和63个肝功能稳定病人切除肝的组织芯片中进行验证。最后将蛋白表达量和临床参数纳入Kaplan-Meier生存率和Cox回归分析。结论:外泌体来源的galectin-9可作为预测肝移植术后排斥发生及预后的生物学指标。  相似文献   
2.
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/(m^2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress.  相似文献   
3.
Lipids changes in liver cancer   总被引:9,自引:1,他引:8  
Liver is one of the most important organs in energy metabolism. Most plasma apolipoproteins and endogenous lipids and lipoproteins are synthesized in the liver. It depends on the integrity of liver cellular function, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs, these processes are impaired and the plasma lipid and lipoprotein patterns may be changed. Liver cancer is the fifth common malignant tumor worldwide, and is closely related to the infections of hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV infections are quite common in China and other Southeast Asian countries. In addition, liver cancer is often followed by a procession of chronic hepatitis or cirrhosis, so that hepatic function is damaged obviously on these bases, which may significantly influence lipid and lipoprotein metabolism in vivo. In this review we summarize the clinical significance of lipid and lipoprotein metabolism under liver cancer.  相似文献   
4.
研究胡子鲶胃、前肠、中肠、肝胰脏四个部位的主要消化酶(蛋白酶、淀粉酶、脂肪酶)活性以及温度、pH对其的影响.结果表明:在四个部位中,蛋白酶活力由高到低依次为:胃〉前肠〉肝胰脏〉中肠;淀粉酶活力由高到低依次为:肝胰脏〉中肠〉胃〉前肠;脂肪酶活力由高到低依次为:前肠〉中肠〉胃〉肝胰脏.胃蛋白酶活性最高,其适宜温度为30-35℃。适宜pH为5.5;肝胰脏淀粉酶活性最高,其适宜温度为25~35℃。适宜pH为6.0~7.0;前肠脂肪酶活性最高,其适宜温度为35-40℃,适宜pH为7.0~7.5.  相似文献   
5.
目的:研究耐力运动对高脂膳食诱导的C57BL/6J脂肪肝小鼠肝脏UCP2及Mn-SOD表达与脂肪肝的关系.方法:以高脂膳食诱导的脂肪肝小鼠为模型,分析耐力运动20周后肝脏UCP2及Mn-SOD表达变化与肝脏脂肪变的关系.结果:肝脏UCP2与Mn-SOD在高脂膳食组(HS组)均显著升高;恢复正常膳食结合耐力运动20周组(RE组),Mn-SOD表达进一步升高,而UCP2表达显著降低.HS组形成明显的脂肪肝,恢复正常膳食加20周不运动组与恢复正常膳食结合20周耐力运动组脂肪肝得到明显改善,但RE组改善更为明显.结论:耐力运动可能以上调Mn-SOD表达而下调UCP2表达,达到既清除活性氧又减少肝脏线粒体ATP合成降低目的,从而保护肝脏免受过多活性氧和ATP耗尽的损伤.  相似文献   
6.
图像特征提取是图像处理的一个主要环节,是图像处理技术研究和应用的一个重要领域。本文选取了新疆地方性肝包虫病中的单囊型肝包虫和正常肝脏CT图像进行研究,提取了灰度直方图、灰度共生矩阵(GLCM)、kc复杂性三种特征组成综合图像特征。首先对图像进行尺寸归一、去噪、对比度增强的预处理,并对综合特征进行统计学分析,最后应用Fisher判别分析法对特征的分类能力进行评价。实验结果表明运用综合特征对图像分类有较高的准确率,这对基于内容的新疆肝包虫病CT图像的检索的研究奠定了一定的基础。  相似文献   
7.
8.
宋亚军  马伟  郝梅 《体育科学》2004,24(7):25-27
采用实验法,探讨一次性长时间运动后及恢复期大鼠脑组织一氧化氮(NO)和一氧化氮合成酶(NOS)的变化以及中药对其调节性作用。研究结论:急性耐力运动后大鼠端脑iNOS活性显著性增高、cNOS显著性降低,而NO水平的过量提高可能具有神经毒性作用,这可能是急性耐力运动引发运动性中枢疲劳的重要原因;急性耐力运动后20h恢复期,大鼠端脑NO及其合成酶系的变化趋势与病理性脑损伤存在明显差异,这可能与急性耐力运动中脑组织L-精氨酸分解代谢加速和脂质过氧化水平提高有关;中药营养补充对减缓急性耐力运动中NO过量增高、保护脑组织、推迟中枢疲劳的产生具有一定的积极性作用。  相似文献   
9.
To study the protective role of Arogh on isoproterenol induced myocardial damage in rats. The effect of Arogh pretreatment on isoproterenol induced myocardial damage was assessed by studying the levels of lipid peroxides and changes in the activity of marker enzymes such as creatine kinase, lactate dehydrogenase and transaminases in serum and heart tissue. In isoproterenol administered rats, a significant decrease was observed in the activity of marker enzymes in the heart with a corresponding increase in their levels in serum. Lipid peroxide levels increased significantly in the serum and heart. In rats pretreated with arogh, the level of lipid peroxides and the activity of marker enzymes were maintained at near normal values. Pretreatment with Arogh offered a protective effect against isoproterenol induced myocardial damage in rats as evidenced by LDH isoenzyme patterm and histopathological studies of heart tissue.  相似文献   
10.
Serum creatinine does not distinguish between various causes of graft dysfunction. Serial assay of proximal tubular enzymes N-Acetyl-D-glucosaminidase (NAG), Alanine aminopeptidase (AAP) and Gamma glutamyl transferase (GGT) in urine was done to assess their usefulness in distinguishing various causes of graft dysfunction. Daily serum creatinine and enzymuria were measured in 32 consecutive renal allograft recipients for first 15 postoperative days. Graft dysfunction was defined as >20% increase in serum creatinine and >100% increase in enzymuria over the baseline. The diagnosis of graft dysfunction was based upon clinical criteria, ultrasonography, cyclosporin trough level, allograft biopsy, response to anti-rejection therapy and alteration of cyclosporin dosage. Fifteen episodes of graft dysfunction were identified in 15 patients. The sensitivity and specificity of the enzymes (NAG, AAP and GGT) for predicting graft dysfunction were 87.5%, 86.9%, 88.5% and 98.2%, 98.2%, 97.9% respectively. There was a significant increase in enzymuria during acute tubular necrosis (ATN) and acute rejection episode compared to cyclosporin nephrotoxicity (p<0.01). Enzymuria assay provides a simple, reliable and noninvasive method to distinguish cyclosporin nephrotoxicity from acute tubular necrosis and acute rejection in renal allograft recipients.  相似文献   
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