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排序方式: 共有363条查询结果,搜索用时 15 毫秒
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赛庚啶对氧自由基的清除作用 总被引:18,自引:0,他引:18
赛庚啶(Cyp)对Fenton反应生成的·OH有较强的直接清除作用(EC50为54μmol/L),并明显抑制·OH的生成速率(IC50为22 μmol/L),且作用明显比·OH特异性清除剂甘露醇强(其EC50和IC50分别为22.7 mmol/L和10.7mmol/L)。Cyp对大鼠腹腔多形核白细胞(PMNs)产生的O2也有一定的清除作用,其IC50为179 μmol/L。提示Cyp的抗心肌损伤作用可能至少部分与其清除氧自由基作用相关。 相似文献
84.
Diabetes mellitus encompasses a group of chronic metabolic conditions associated with cardiovascular complications such as atherosclerosis, cardiomyopathy and nephropathy. In the present study, the authors investigated the beneficial effects of swertiamarin in diabetes and its associated cardiovascular complications in Zucker fa/fa rats. Six male Zucker fa/fa rats in each group were treated for 28 days with swertiamarin (75 mg/kg/day, intraperitoneally) or pioglitazone (30 mg/kg orally). Blood samples were collected and evaluated for several parameters. Elevated serum glucose, triglyceride, nonesterified free-fatty acid and cholesterol levels were found in untreated Zucker fa/fa rats. Serum matrix metalloproteinase (MMP)-9 and MMP-3 levels were also found to be significantly higher in untreated Zucker fa/fa rats. Treatment with swertiamarin significantly (P<0.05) reduced serum glucose, triglyceride, nonesterified free-fatty acid and cholesterol levels, and also reduced serum MMP-9 and MMP-3 levels compared with untreated rats. Swertiamarin also significantly (P<0.05) decreased serum levels of urea compared with untreated Zucker fa/fa rats. Overall, the data suggest that swertiamarin produced beneficial effects with respect to diabetes-induced cardiovascular complications such as atherosclerosis and nephropathy. A swertiamarin-induced decrease in serum MMP-9 and MMP-3 levels is one of the possible mechanisms responsible for improvement of these complications. 相似文献
85.
Physician support for diabetes patients and clinical outcomes 总被引:1,自引:0,他引:1
Jochen Gensichen Michael Von Korff Carolyn M Rutter Michelle D Seelig Evette J Ludman Elizabeth HB Lin Paul Ciechanowski Bessie A Young Edward H Wagner Wayne J Katon 《BMC public health》2009,9(1):367
Background
Physician practical support (e.g. setting goals, pro-active follow-up) and communicative support (e.g., empathic listening, eliciting preferences) have been hypothesized to influence diabetes outcomes. 相似文献86.
腹腔镜外科发展中的难题与对策 总被引:13,自引:3,他引:10
许红兵 《世界华人消化杂志》1999,7(12):1059-1060
现代外科正在向创伤小,痛苦少,康复快,预后好的趋势发展,腹腔镜外科便是顺应这种趋势的微创外科新技术的主要代表.与传统外科相比,腹腔镜外科具有突出的优点:避免或极少切断腹壁神经或肌肉,使切口疼痛大为减轻,切口并发症大为降低,内脏干扰轻,脏器功能恢复快;手术术野光照良好,图象放大,手术器械精良,颇有点显微外科手术特点,戳孔微小,灵活机动,便于多种外科疾病联合诊治;由于参与手术人员能共睹同一画面,有利于鼎力合作,也便于观摩教学;而且大大减少了传染性疾病对手术人员的威胁,还因能坐下来手术而减轻了劳动强度… 相似文献
87.
In vivo and in vitro MR imaging of renal tumors: histopathologic correlation and pulse sequence optimization 总被引:1,自引:0,他引:1
Quint LE; Glazer GM; Chenevert TL; Fechner KP; Gikas PW; Shireman PK; Grossman HB; Li KC 《Radiology》1988,169(2):359-362
Magnetic resonance (MR) imaging has given mixed results in the detection of renal masses. To identify the reasons for this and to determine the optimal pulse sequences for evaluating renal tumors, the authors imaged 12 primary renal tumors in vivo and 17 in vitro at 0.35 T. Histopathologic findings for each specimen were closely correlated with the MR images. Four of seven solid tumors imaged in vivo were isointense with surrounding normal renal parenchyma at all pulse sequences. The other three tumors were hyperintense in vivo at T2-weighted sequences. At heavily T2-weighted sequences eight solid tumors were hyperintense in vitro and four were hypointense. There was no correlation between signal intensity and specific tissue type or histologic pattern for solid tumors. The five cystic tumors were well seen both in vivo and in vitro on T2-weighted images. However, the signal intensity of the cyst fluid was an unreliable indicator of benignancy. SE MR imaging at 0.35 T has significant limitations in the detection of solid renal masses. 相似文献
88.
89.
S A Morris H B Tanowitz K S Rowin M Wittner J P Bilezikian 《Molecular and biochemical parasitology》1984,13(2):227-234
L6E9 myoblasts infected with Trypanosoma cruzi undergo desensitization to beta-adrenergic catecholamines in a manner distinct from uninfected control myoblasts. Following incubation of intact cells with isoproterenol for 2 h, homogenates prepared from differentiated, high density uninfected L6E9 cells retain isoproterenol-dependent adenylate cyclase activity. In addition, previous exposure to isoproterenol is accompanied by a decrease in the number of beta-adrenergic receptors. Homogenates of high density L6E9 cells infected with T. cruzi retain their adenylate cyclase responsivity to isoproterenol but demonstrate a marked decrease in beta-adrenergic receptors. Following desensitization infected cell homogenates lose their responsiveness to isoproterenol and demonstrate a more marked decrease in beta-receptors. There does not appear to be any effect of T. cruzi infection on affinity of beta-adrenergic agonists for the beta-receptor or on changes in agonist affinity associated with desensitization. Infection of low density undifferentiated cells results in no apparent change in adenylate cyclase activity or in beta-receptors. Their behavior in the setting of desensitization--decreased whole cell cyclic AMP, decreased adenylate cyclase, unchanged beta-receptors--is also not affected by infection. The pattern of desensitization to beta-adrenergic agonists in high density infected cells shares several properties with the pattern of desensitization in low density uninfected cells, suggesting that infection may be associated with part of the more primitive cellular response pattern. 相似文献
90.
学术背景:平衡能力是人体的一项重要生理机能,在人类生活中有非常重要的意义.特别是老年人平衡能力下降,直接影响老年人独立生活能力,严重的会引起老年人跌倒,诱发其他疾病.目的:总结老年人平衡能力的国内外研究现状,并展望未来老年人平衡能力研究的发展方向.检索策略:应用计算机检索PubMed数据库1990-12/2007-06有关老年人平衡能力方面的文章,检索词“elderly,balance“,限定文章语言种类为English,共检索到208篇文章.同时应用计算机检索中国期刊全文数据库、万方数据库1997-12/2007-06的相关文章,检索词“老年人、平衡能力“,限定文章语言种类为中文,共检索到85篇文章.对资料进行初审,选取符合研究要求的有关文章找全文.纳入标准:①平衡能力的研究.②老年人平衡特征.③平衡能力评价.④运动干预对平衡能力的研究.排除理由:①较陈旧的文献.②重复研究.文献评价:共19个研究满足全部纳入标准,予以纳入.其中6篇为老年人平衡特征的文献、8篇平衡评价的文献、5篇运动干预老年人平衡影响的文献.资料综合:①平衡能力是人体相关系统功能的集中表现,研究影响平衡能力的前庭系统、视觉系统、躯体感觉、神经系统及肌肉-骨骼等系统功能增龄性的变化趋势,探究导致平衡能力增龄性变化的主要因素是待解决的问题.②平衡测试是定量评定平衡能力的前提,针对老年群体的特殊性,逐步寻求安全、简捷能全面反映其平衡能力的测试方法.③国内专业人员日益提高了对平衡的关注,发表的论文也较多,但由于平衡评定方法不统一,对中国人民平衡能力增龄性变化的研究没有继承性,研究国民的平衡能力增龄性变化是必要的.④众多研究表明,体育锻炼可以延缓平衡能力的衰退.但研究比较分散,运动项目比较单一,探究利于干预的运动项目以及最佳时机是待解决的热点课题.结论:建立一整套适合中国国民平衡能力评价体系,研究国民的平衡能力增龄性变化是十分有必要的,为全民健身活动中的老年人科学地进行健身提供依据. 相似文献