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排序方式: 共有117条查询结果,搜索用时 31 毫秒
81.
Hui PAN Bao-hui WANG Zhou-bin LI Xing-guo GONG Yong QIN Yan JIANG Wei-li HAN 《Journal of Zhejiang University. Science. B》2019,(4):310-321
目的:通过细胞外过氧化氢(H_2O_2)的刺激建立单个人肺癌SPC-A-1细胞的氧化压力模型。创新点:氧自由基(ROS)涉及多种生物现象,包括有益和有害两个方面。ROS的定量检测和反应网络的评估结果令人期待。但ROS半衰期很短且反应过程很快,因此,我们通过多种手段克服了检测和评估的困难。方法:利用改进的微流控和成像技术测定ROS水平,构建氧反应网络。通过调控线粒体胞浆Ca2+水平、线粒体Ca2+摄取、细胞内ROS自扩增以及内在凋亡途径,确定线粒体在外源氧化压力模式中扮演的角色。结论:研究结果表明1 mmol/L H_2O_2引起细胞O_2·-水平的快速增加,从而导致细胞氧化能力增加和还原能力降低。此外,研究还证实了内质网中储存的Ca2+是H_2O_2诱导的线粒体Ca2+爆发的主要来源。外源氧化压力反应涉及细胞器间Ca2+信号的传递、ROS自身扩增、线粒体功能紊乱和半胱天冬酶依赖性凋亡途径。线粒体在外源性氧化应激影响细胞命运方面发挥着关键作用。 相似文献
82.
V. N. Thorat A. N. Suryakar A. S. Sardeshmukh S. S. Sarawade 《Indian journal of clinical biochemistry : IJCB》2004,19(2):32-35
In the present study, the role of serum lipid peroxide and serum nitric oxide as oxidants and erythrocytic superoxide dismutase
& serum vitamin E as antioxidants were determined in the 50 neonates with hypoxic ischaemic encephalopathy. (HIE) as against
25 healthy neonates as controls 50 patients of HIE were further divided into two groups i. e. mild and moderate HIE patients.
All subjects were in the age group of 37–41 weeks of gestation. The levels of serum lipid peroxide, serum nitric oxide and
erythrocytic superoxide dismutase were significantly elevated in both groups of neonates with HIE than those of controls (P<0.001),
whereas serum vitamin E levels were significantly decreased in both groups of HIE patients than those of controls (P<0.001).
A positive correlation was obtained between serum lipid peroxide and erythrocytic superoxide dismutase (r=+0.86). Alterations
in the status of oxidants and antioxidants indicate role of free radicals in the development of HIE. 相似文献
83.
Alcohol induced oxidative stress is linked to the metabolism of ethanol. In this study it has been observed that administration
of ethanol in lower concentration caused gain in body and liver weight. while higher concentration of ethanol caused lesser
gain in body and liver weight. Ethanol treatment enhanced lipid peroxidation significantly, depletion in levels of hepatic
glutathione and ascorbate, accompanied by a decline in the activities of glutathione peroxidase and glutathione reductase,
and increased in hepatic glutathione s-transferase activity. Interestingly catalase activity increases in lower concentration
of ethanol exposure, and decreased in higher concentration. Superoxide dismutase activity was also increased on ethanol exposure.
But, ethanol feeding did not show any effect on glucose-6-phosphate dehydrogenase activity. Ethanol ingestion perturbs the
antioxidant system in a dose and time dependent manner. 相似文献
84.
Ethanol-induced liver injury may be linked, at least partly, to an oxidative stress resulting from increased free radical
production and/or decreased antioxidant defence. Distinguishing alcoholic and non-alcoholic liver disease has important implications.
This study looked at the possible changes between alcoholic and non-alcoholic liver diseases by examining the presence of
oxidative damage, as monitored by several parameters relating to oxidative stress. Lipid peroxides concentration, superoxide
dismutase activity and glutathione S-transferase activity increased, where as glutathione content, glutathione peroxidase
activity and glutathione reductase activity decreased among the tested subjects in comparison to normal healthy group. Determination
of these parameters may be valuable in the evaluation of liver disease. However, oxidative stress related enzymes and non-enzymes
can not be utilized as a marker for alcoholic liver diseases, as these parameters responded in the same way after liver is
damaged irrespective of their cause. Their level may help in determining the degree of liver damage. Degree of oxidative injury
was similar in patients with non-alcoholic liver disease and in moderate drinkers; while significantly higher in heavy drinkers.
The differences between the groups might be based on the type of liver pathological condition rather than its etiology (i.e.
alcohol and non alcohol related causes). 相似文献
85.
目的:为探讨经导管射频消融术对心脏和心脏自主神经的急性期损伤。方法:选择接受射频消融术的阵发性室上性心动过速病人120例,在术前,术后进行超氧化物歧化酶测定和心率变异性分析。结果:射频消融术后超氧化物歧化酶较术前明显增高(P<0.01);术后心率变异性的各项频域和时域指标均降低,但与超氧化物歧化酶变化无明显相关,结论:射频消融术对心脏和心脏自主神经的急性期损伤是存在的,但术后心率变异性的降低是由于射频电流损伤心脏迷走神经所致,与手术引起的心肌应激性损伤无关。 相似文献
86.
Subcutaneous administration of monosodium glutamate (MSG), to normal adult male mice, for six consecutive days at dose levels
of 4 and 8 mg/g body weight, significantly increased the level of free radical initiating enzyme, xanthine oxidase, whereas
the activity of free radical scavenging enzymes, like catalase and superoxide dismutase was significantly decreased in hepatic
tissue. These observations suggested that ingestion of MSG at dose level of 4 mg/g body weight and above, induced oxidative
stress in the hepatic tissue of adult male mice. 相似文献
87.
Krishna Mohan Surapneni V. S. Chandrasada Gopan 《Indian journal of clinical biochemistry : IJCB》2008,23(1):41-44
The changes in the erythrocyte lipid peroxidation products (MDA), levels of glutathione (GSH), ascorbic acid and plasma vitamin
E (non enzymatic antioxidant parameters) and activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase
(GPX), catalase in erythrocytes and plasma glutathione - S - transferase (GST) activity were estimated in patients with rheumatoid
arthritis. This work was undertaken to assess oxidative stress and anti oxidant status in patients with rheumatoid arthritis.
It was observed that there was a significant increase in erythrocyte MDA levels, activities of SOD, GPX, plasma GST and a significant decrease in erythrocyte GSH, ascorbic acid, plasma vitamin E levels and catalse activity in
patients with rheumatoid arthritis when compared to controls. The results of our study suggests higher oxygen free radical
production, evidenced by increased MDA and decreased GSH, ascorbic acid, vitamin E and Catalase activity, support to the oxidative
stress in rheumatoid arthritis. The increased activities of antioxidant enzymes may be a compensatory regulation in response
to increased oxidative stress. 相似文献
88.
Forty cases of head and neck cancer were studied for plasma superoxide dismutase, malondialdehyde and thiol levels and results
were compared with a group of forty normal healthy volunteers. Mean plasma superoxide dismutase activity was not found to
be altered while malondialdehyde concentration was significantly higher when compared with the control group. On the other
hand, mean thiol level was significantly lowered. The data suggests increased level of oxidative stress in patients with head
and neck cancer. 相似文献
89.
N. Ananth Ganesh B. Balaji D. M. Vasudevan MD FRC Vivian D’Souza Ashalatha V. Rao Dinesh Nambiar 《Indian journal of clinical biochemistry : IJCB》1998,13(2):126-128
In a pilot study with five oral cancer patients undergoing radiotherapy (RT) three were given Granulocyte Macrophage Colony
Stimulating Factor (GM-CSF) as a protective agent to reduce the mucosal inflammation during radiotherapy. The myeloperoxidase
(MPO) enzyme activity in WBC was quantitated. The three patients showed a significant increase in the MPO activity when compared
with two untreated controls indicating the efficacy of GM-CSF as a protective agent. It is suggested that further detailed
studies with larger number of patients would be useful. 相似文献
90.
超氧化物歧化酶(SOD)样活性的测定主要依赖于超氧阴离子自由基(O2-·)在不同条件下的受控产生,目前产生O2-·的方法主要有邻苯三酚自氧化法、肾上腺素自氧化法、黄嘌呤氧化酶法、核黄素光照法、碱性二甲基亚砜砜法和碱性连二亚硫酸钠法等,各种方法的模型体系对SOD活性的测定结果均有不同的准确性和灵敏度。 相似文献