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Fei-Yi Wu Chen-Yuan Hsiao Chih-Pei Ou-Yang Chang-Chi Lai Yi-You Wang Zen-Chung Weng Cheng-Hsiung Huang 《Journal of the Chinese Medical Association》2013,76(9):497-503
BackgroundWe previously reported that pressure overload of the left ventricle reduced myocardial infarct (MI) size in rabbits. The threshold of pressure overload was investigated in this study.MethodsPressure overload of the left ventricle was induced by partial snare of the ascending aorta in anesthetized, open-chest rabbits. Systolic left ventricular pressure (SLVP) was elevated 50% or 30% above baseline value by varying the degree of partial snaring. Different duration of pressure overload, including 10 minutes, 5 minutes, 3 minutes, or 2 minutes, was applied to determine the threshold of protective effects. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions and reperfusions. Ten minutes after different pretreatment, 1 hour occlusion of the left anterior descending coronary artery followed by 3 hours reperfusion was done to induce MI. The size of area at risk and MI were determined by blue dye injection and triphenyl tetrazolium chloride staining after experiments.ResultsPressure overload increase of SLVP 50% above baseline value for 10 minutes, 5 minutes, and 3 minutes significantly reduced MI size (18.5 ± 3.6%, 21.4 ± 1.9% and 21.6 ± 1.7%, respectively, vs. 26.6 ± 1.0% in the control group, mean ± standard deviation, p < 0.01). A 30% increase of SLVP by pressure overload for 10 minutes, 5 minutes and 3 minutes also significantly decreased MI size (20.5 ± 2.5%, 21.6 ± 2.3%, and 21.5 ± 2.3%, p < 0.01). Ischemic preconditioning significantly decreased MI size (19.9 ± 2.8%, p < 0.001). Pressure overload to elevate SLVP 50% or 30% above baseline value for 2 minutes did not significantly alter MI size (25.0 ± 2.3% and 26.0 ± 1.7%, p = 0.122 and p = 0.457). Two episodes of 2 minutes pressure overload did not significantly decrease MI size (25.0 ± 2.2% and 25.5 ± 2.2%, p = 0.118 and p = 0.281). The hemodynamics, area at risk, and mortality were not significantly different among all groups of animals.ConclusionPressure overload to raise SLVP either 50% or 30% above baseline value reduced MI size. A minimum duration of 3 minutes was necessary to induce the protective effects. 相似文献
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Rebecca S. Lipner Weifeng Weng Kelly J. Caverzagie Brian J. Hess 《Advances in health sciences education : theory and practice》2013,18(5):1029-1045
Given the rising burden of healthcare costs, both patients and healthcare purchasers are interested in discerning which physicians deliver quality care. We proposed a methodology to assess physician clinical performance in preventive cardiology care, and determined a benchmark for minimally acceptable performance. We used data on eight evidence-based clinical measures from 811 physicians that completed the American Board of Internal Medicine’s Preventive Cardiology Practice Improvement ModuleSM to form an overall composite score for preventive cardiology care. An expert panel of nine internists/cardiologists skilled in preventive care for cardiovascular disease used an adaptation of the Angoff standard-setting method and the Dunn-Rankin method to create the composite and establish a standard. Physician characteristics were used to examine the validity of the inferences made from the composite scores. The mean composite score was 73.88 % (SD = 11.88 %). Reliability of the composite was high at 0.87. Specialized cardiologists had significantly lower composite scores (P = 0.04), while physicians who reported spending more time in primary, longitudinal, and preventive consultative care had significantly higher scores (P = 0.01), providing some evidence of score validity. The panel established a standard of 47.38 % on the composite measure with high classification accuracy (0.98). Only 2.7 % of the physicians performed below the standard for minimally acceptable preventive cardiovascular disease care. Of those, 64 % (N = 14) were not general cardiologists. Our study presents a psychometrically defensible methodology for assessing physician performance in preventive cardiology while also providing relative feedback with the hope of heightening physician awareness about deficits and improving patient care. 相似文献
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目的探讨凝血酶原基因3’端非翻译区20210 G/A多态性与中国汉族人群肺血栓栓塞症(PTE)发生的相关性。方法采用病例-对照研究,病例组为经放射性核素肺通气/灌注显像和(或)螺旋CT肺动脉造影(CTPA)检查,并结合临床资料确诊的PTE患者101例;对照组为与PTE患者来自相同地区,性别、年龄相匹配的健康对照101例。应用碘化钾-氯仿-异丙醇法提取基因组。应用聚合酶链反应(PCR)、HindⅢ限制性内切酶片段长度多态性分析(RFLP)及聚丙烯酰胺凝胶电泳(PAGE)等方法检测凝血酶原G20210多态性。结果健康对照人群GⅡ20210A位点的基因频率符合Hardy-Weinberg平衡定律,PTE病例组及对照组GⅡ20210A位点均为野生型(GG)纯合子,GA、AA基因型频率为0,A等位基因频率为0。结论凝血酶原G20210A基因多态性与中国汉族人群PTE发生可能无关。 相似文献
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目的探讨颗粒子宫腺(GMG)细胞中血管内皮生长因子(VEGF)的表达。方法取妊娠13~15 d昆明种小鼠的子宫腺细胞区,经组织块培养提纯GMG细胞,应用免疫组织化学及Western blot法显示GMG细胞中VEGF。结果组织块培养时GMG细胞生长状况好,细胞纯度高,在GMG细胞及其培养液中均有VEGF表达。结论GMG细胞表达和分泌VEGF。 相似文献
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目的 构建个性化知识图谱技术和定性访谈法结合,进一步挖掘张忠德教授辨治间质性肺疾病临证特征与用药规律。方法 采用回顾性分析,系统收集张忠德教授广东省中医院门诊2010年8月至2020年8月治疗间质性肺疾病病历,按照诊断标准、纳入标准、排除标准,严格筛选后,通过广东省中医院大数据挖掘团队中医药大数据智能处理与知识服务系统进行数据挖掘分析,并通过多元化视觉定性访谈法,将定量与定性分析有效结合。结果 共筛选出347首方,共141味药物,常用药物频次 ≥ 84次的药物有10味,其中党参、麦芽、黄芪、紫菀、白术等为核心用药,通过症状与药物推理知识地图显示,党参、炒麦芽、黄芪、大枣、太子参、山萸肉、巴戟天等为主要治疗用药;临证遣方用药知识关联分析,得知咳嗽、耳鸣、心悸、水肿、头痛、胸闷、恶寒等为多见,针对咳嗽,首选紫苏子、橘红、桂枝等温肺降气通阳之品等;频繁聚集显示,常用药对炒麦芽-炒白术、黄芪-党参、黄精-菟丝子、前胡-紫菀、炙枇杷叶-浙贝母等;聚类分析结果得到4组关系密切的聚类新药物组合;以脾为中轴,肺肾共扶为主的“平调五脏论”,分期阶梯辨治间质性肺疾病。结论 张忠德教授认为间质性肺疾病,虚实夹杂为多见,应从肺、脾、肾着手,采用平调五脏论分期阶梯辨治,用药配伍精简,以和为贵,以平为期。 相似文献
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Jin-Ming Cen Jie Cheng Qing-Yuan Xiong Bai-Qiang Mei Wei-Biao Cai Xi-Li Yang 《慢性疾病与转化医学(英文)》2015,1(2):105-109
ObjectiveThis study explores the correlation between plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) and coronary heart disease (CHD) by comparing the level of plasma Lp-PLA2 in the plasma of patients with different types of CHD.MethodsBlood samples were collected from 56 patients diagnosed with CHD by the Department of Cardiology of the First People''s Hospital of Foshan and 34 healthy subjects from February 2013 to January 2014. We measured the concentration of plasma Lp-PLA2 and determined the levels of total cholesterol (Tch), triglyceride (TG), apolipoprotein A1 (Apo-A1), apolipoprotein B (Apo-B), high density lipoprotein-cholesterol (HDL-c), low density lipoprotein-cholesterol (LDL-c), lipoprotein a (Lp(a)), glucose (Glu), and high-sensitivity C-reactive protein (hs-CRP). The concentration of plasma Lp-PLA2 in the healthy control group and each subgroup of CHD patients were compared and analyzed for correlations of plasma Lp-PLA2 between the patients in different CHD subgroups and several laboratory indicators.ResultsThe concentration of plasma Lp-PLA2 in each subgroup of CHD was significantly higher than in the control group (P < 0.05). The concentration of Lp-PLA2 in the unstable angina pectoris (UAP) group and acute myocardial infarction (AMI) group were significantly higher than in the stable angina pectoris (SAP) group (P < 0.05), and the concentration of plasma Lp-PLA2 in the AMI group was significantly higher than in the UAP group (P < 0.05). The concentration of plasma Lp-PLA2 in the CHD group merely showed a positive correlation (r = 0.493, P < 0.05) with the hs-CRP group, but the levels of Tch, TG, Apo-A1, Apo-B, HDL-c, LDL-c, Lp(a) and Glu did not.ConclusionsThe concentration of plasma Lp-PLA2 in patients with CHD was higher than that in the control group. The concentration of plasma Lp-PLA2 in the subgroups of CHD patients varied greatly from each other. The inflammatory response of atherosclerosis might be resulted from the synergy of plasma Lp-PLA2 and hs-CRP. 相似文献
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Alpha‐phellandrene‐induced DNA damage and affect DNA repair protein expression in WEHI‐3 murine leukemia cells in vitro 下载免费PDF全文
Jen‐Jyh Lin Chih‐Chung Wu Shu‐Chun Hsu Shu‐Wen Weng Yi‐Shih Ma Yi‐Ping Huang Jaung‐Geng Lin Jing‐Gung Chung 《Environmental toxicology》2015,30(11):1322-1330
Although there are few reports regarding α‐phellandrene (α‐PA), a natural compound from Schinus molle L. essential oil, there is no report to show that α‐PA induced DNA damage and affected DNA repair associated protein expression. Herein, we investigated the effects of α‐PA on DNA damage and repair associated protein expression in murine leukemia cells. Flow cytometric assay was used to measure the effects of α‐PA on total cell viability and the results indicated that α‐PA induced cell death. Comet assay and 4,6‐diamidino‐2‐phenylindole dihydrochloride staining were used for measuring DNA damage and condensation, respectively, and the results indicated that α‐PA induced DNA damage and condensation in a concentration‐dependent manner. DNA gel electrophoresis was used to examine the DNA damage and the results showed that α‐PA induced DNA damage in WEHI‐3 cells. Western blotting assay was used to measure the changes of DNA damage and repair associated protein expression and the results indicated that α‐PA increased p‐p53, p‐H2A.X, 14‐3‐3‐σ, and MDC1 protein expression but inhibited the protein of p53, MGMT, DNA‐PK, and BRCA‐1. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1322–1330, 2015. 相似文献