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41.
Mariani J Ou R Bailey M Rowland M Nagley P Rosenfeldt F Pepe S 《The Journal of thoracic and cardiovascular surgery》2000,120(4):660-667
BACKGROUND: Recovery of cardiac function after cardiac surgery and other interventional cardiac procedures in elderly patients is inferior to that in younger patients, suggesting that the aged myocardium is more sensitive to ischemia and other stresses. Although convincing data from animal studies of senescence now exist, there is a dearth of controlled in vitro studies that examine the specific response of aged human myocardium to the stress of hypoxia or ischemia. OBJECTIVE: We sought to determine the effect of age on the capacity of human atrial trabeculae to recover contractile function after in vitro hypoxic or ischemic stress. METHODS: Atrial pectinate trabeculae were dissected from the tip of 58 right atrial appendages harvested during an operation in patients aged between 34 and 89 years and electrically stimulated at 1 Hz in oxygenated Ringer's solution at 37 degrees C. Tissues experienced 30 minutes of either hypoxia (N(2) and perfusate) or simulated ischemia (humidified N(2) without perfusate) and were returned to normoxia for recovery of function for 30 minutes. Developed force and other contractile variables were determined during each period. RESULTS: Under normoxic conditions, no significant age difference was observed for any contractile function variable. However, after hypoxia, the old (70-89 years) and intermediate age groups (60-69 years) showed reduced recovery of developed force (48.5% +/- 22.2% [n = 11] and 44.9% +/- 19% [n = 12], respectively) compared with that found (66.4% +/- 19.7% [n = 15]) in the younger (34-59 years) group (mean +/- SD, P =.02). Similarly, after simulated ischemia, the groups of 70- to 89-year-old and 60- to 69-year-old subjects showed reduced recovery of developed force (35.7% +/- 17% [n = 5] and 51.1% +/- 11.8% [n = 9], respectively) compared with that found (68.2% +/- 10.4% [n = 6]) in the group of 34- to 59-year-old subjects (P =.01). Multivariable analysis, comparing 20 factors of surgical patient characteristics and recovery of developed force, found that only age (P =.01) and hypertension (P =.01) were predictors of reduced recovery of developed force after either hypoxia or simulated ischemia. CONCLUSIONS: In aged human atrial myocardium, the capacity to recover contractile function after in vitro hypoxia or simulated ischemia is reduced compared with the younger myocardium of mature adults. These findings suggest that enhanced myocardial protective strategies may be indicated for elderly patients undergoing cardiac surgery. 相似文献
42.
SARS与急性上呼吸道感染中医证候分型及指标数量化方法的探讨 总被引:7,自引:0,他引:7
目的 探讨早期SARS与急性上呼吸道感染患者中医证候及四诊指标数量化,为中医证候客观化研究提供方法 学参考.方法 应用自编急诊发热病例中医证候观察表,收集急诊SARS患者与急性上呼吸道感染患者中医临床四诊信息,建立数据库,运用样品聚类分析及频数归一化权重分析.结果 早期SARS患者的中医证型主要有两型;急性上呼吸道感染患者早期证候主要有三个证型.结论 样品聚类分析与频数归一化权重方法 可用于SARS患者与急性上呼吸道感染患者的中医证候客观化研究,也可用于其他病的中医证候客观化研究. 相似文献
43.
福建省469例健康咨询热线电话记录分析 总被引:3,自引:0,他引:3
目的了解福建省接受健康咨询热线的主要对象的特征以及求询的主要内容,为今后开展健康教育和行为干预提供依据。方法选取2004年1月至2005年2月接受电话咨询者469例资料进行分析,按咨询内容(性病艾滋病、寻医问药、生殖生育和心理卫生)进行分类整理,数据采用SPSS 11.5统计软件包进行统计分析。结果求询者中,男性占66.74%,女性占33.26%;年龄以29岁以下青年人居多,占49.89%;职业以工人(打工族)居首位,占48.83%;文化程度主要是初中以下人员,占60.77%;咨询内容涉及性病艾滋病问题最多,占45.42%。结论本热线求询者以男性中青年为主,大部分文化程度偏低,且多数有高危行为。利用咨询热线,对求询者进行心理、行为等健康教育具有积极意义。 相似文献
44.
45.
目的:本文观察香菇多糖对恶性肿瘤患者围化疗期肺部感染抗生素治疗的增效作用。方法:120例围化疗期发生肺部感染恶性肿瘤患者在接受抗生素治疗的同时,随机分成加用香菇多糖针和不加香菇多糖针静脉滴注两组。每组各60例。结果:接受抗生素及香菇多糖联合治疗的患者的有效率显著提高(P〈0.05).临床症状、体征与X光胸部片改善时间大幅缩短。结论:香菇多糖对恶性肿瘤患者围化疗期肺部感染抗生素治疗有明显增效作用。 相似文献
46.
47.
Hui Tian Junhai Ou Stephen C Strom Raman Venkataramanan 《Drug metabolism and disposition》2005,33(3):329-335
Hepatic regeneration is very critical to the success of living donor liver transplantation, which allows a reduced size liver to grow in size to accommodate the requirements of both the donor and the recipient. The objectives of this study were to evaluate 1) the hepatic metabolism of the two immunosuppressive drugs, tacrolimus and mycophenolic acid (MPA), and 2) the pharmacokinetics of tacrolimus and mycophenolic acid at various time points after initiation of hepatic regeneration by partial hepatectomy in rats. The hepatic intrinsic clearance of tacrolimus was decreased to 70% and 51% of the control level at the 24th h and the 6th day, respectively, but returned to normal level by day 14. The total body clearance of tacrolimus was reduced transiently but recovered completely by day 18. The hepatic intrinsic clearance of MPA was decreased to 52% and 51% of that in control rats at the 24th h and the 6th day, respectively, but recovered to normal level by day 14. The total body clearance of MPA was reduced at the 24th h but recovered by day 6. The magnitude of reduction in the clearance of tacrolimus and MPA was much smaller than what was predicted from in vitro data. The elimination clearance of MPA glucuronide was also impaired during hepatic regeneration but recovered to normal level with time. In conclusion, the pharmacokinetics of tacrolimus and mycophenolic acid were altered during hepatic regeneration but recovered completely at different rates over time. Caution must be exercised in extrapolating in vitro data to in vivo conditions during hepatic regeneration. 相似文献
48.
波依定与洛汀新治疗不同中医证型高血压疗效比较 总被引:6,自引:0,他引:6
目的:观察波依定与洛汀新对不同中医证型高血压的疗效是否具有中草药的某些特征,能否按中医辨证选择抗高血压药.方法:按照WHO的标准明确高血压诊断与分级,根据<中药新药临床研究指导原则>分为4型.216例患者随机分为两组,分别给予波依定与洛汀新治疗,疗程4周.分析对总体血压和不同证型血压的影响,以及对不同症状的疗效有无差异.结果:两种药物降低患者总体血压的幅度基本相同;但分层研究,对4种中医证型患者的血压的降低程度明显不同,洛汀新对肝火亢盛型血压降低幅度更明显,波依定对痰湿壅盛型比其它三型降压更好;对阴虚阳亢型和阴阳两虚型两组之间差异无显著性.对各种证型症状的改善作用也显示同样的结果.结论:抗高血压药对不同中医证型高血压的疗效不同,表明西药也同样具有中草药的某些特性,可以根据中医辨证选择抗高血压药. 相似文献
49.
Solitary fibrous tumors of the pleura: clinical, radiological, surgical and pathological evaluation. 总被引:2,自引:0,他引:2
S C Lee C Tzao S M Ou H H Hsu C P Yu Y L Cheng 《European journal of surgical oncology》2005,31(1):84-87
AIMS: To report a clinicopathological series of cases of solitary fibrous tumor of the pleura from Taiwan. METHODS: Clinical data was collected from a review of medical records and telephone interviewing for follow-up. RESULTS: Eight patients, three men and five women aging from 34 to 71 years, underwent tumor resection and were followed in a period from 7 months to 13.5 years. Six patients underwent standard thoracotomy and two had VATS for tumor excision. Tumors were pathologically benign in seven patients and malignant in one. Patients were all alive with no evidence of tumor recurrence at the time of this report. CONCLUSIONS: One should always consider SFTPs as potentially malignant tumors. Complete resection remains the mainstay of cure. Standard thoracotomy should always be considered when a high suspicion of malignancy is raised, whereas VATS may be a preferred approach for smaller tumors. 相似文献
50.
目的构建人凋亡诱导因子(AIF)基因功能片段的真核表达载体pcDNA3.1( )AIF,并初步研究AIF在细胞凋亡中的作用。方法从人细胞中提取总RNA,RTPCR扩增AIF基因片段;克隆到pMD18T载体上,通过酶切和测序进行鉴定;将AIF基因片段插入pcDNA3.1( ),构建真核表达载体;电转化淋巴母细胞Raji细胞,观察AIF的表达水平和功能。结果成熟AIF蛋白分子在真核细胞中表达,并转移到细胞核中,诱导Caspase非依赖性细胞凋亡。结论成功构建了pcDNA3.1( )AIF真核表达载体,AIF在Caspase非依赖性细胞凋亡中发挥重要作用。 相似文献