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861.
The present study investigated the influence of different frequencies of moderate exercise (13 weeks of treadmill running at 60% of maximal oxygen consumption) on oxidative stress in the heart and liver in rats. Oxidative stress was evaluated by chemiluminescence and lipid peroxidation (LPO) through thiobarbituric acid reactive substances. Activities of superoxide dismutase (SOD), glutathione peroxidase (GHPx) and catalase (CAT) were also measured. The animals were divided into four groups: control (C), acute ([A], only one exercise session at the end of 13 weeks), low frequency ([LF], one session a week for 13 weeks) and high frequency ([HF], five sessions a week for 13 weeks). Chronic exercise promoted cardiac hypertrophy in the HF group. Myocardial LPO in groups A and LF was increased, whereas in the HF group, it was decreased when compared with group C. The HF group demonstrated decreased myocardial SOD and GHPx activities and increased CAT activity. All exercise groups exhibited an increase in LPO in the liver compared with group C. SOD activity in liver was lower in the HF group and higher in the LF group as compared with group C. GHPx activity was higher in group A in relation to group C. Hepatic CAT activity was higher in groups A, LF and HF. It is suggested that chronic exercise training at a submaximal level is better than infrequent exercise bursts to promote metabolic adaptations that minimize oxidative stress.  相似文献   
862.
Malpass  TW; Hanson  SR; Savage  B; Hessel  EA d; Harker  LA 《Blood》1981,57(4):736-740
Cardiopulmonary bypass in baboons produced transient severe platelet dysfunction (bleeding times prolonged to 27.8 +/- 1.4 min compared with 3.9 +/- 0.7 baseline) that was associated with a parallel release of platelet alpha-granule proteins into plasma (platelet factor 4 and beta- thromboglobulin levels of 28.8 +/- 9.3 and 20.0 +/- 1.8 ng/ml, respectively) and their clearance into urine with a reciprocal depletion from circulating platelets. In contrast, platelet-dense granules did not undergo significant release. The bleeding times normalized rapidly following bypass (8.5 +/- 1.4 min at 1 hr). The infusion of prostacyclin (PGI2) into the bubble oxygenator during bypass (40--80 ng/kg/min) prevented the prolongation in bleeding time (p less than 0.01 compared with untreated control values) but did not block the release of alpha-granule proteins. Dosages outside this range were associated with prolonged bleeding times. These results show that transient platelet dysfunction occurring during cardiopulmonary bypass represents activation of platelets independent of alpha or dense granule release and is blocked by potent short-acting inhibition of platelet function using PGI2 infused into the oxygenator apparatus at optimal therapeutic doses.  相似文献   
863.

Background  

The summer of 2007 was the wettest in the UK since records began in 1914 and resulted in severe flooding in several regions. We carried out a health impact assessment using population-based surveys to assess the prevalence of and risk factors for the psychosocial consequences of this flooding in the United Kingdom.  相似文献   
864.
865.
866.

Background  

Intermittent hypoxia (IH), a model of sleep apnea, produces weight loss in animals. We hypothesized that changes in brown adipose tissue (BAT) function are involved in such phenomenon. We investigated the effect of IH, during 35 days, on body weight, brown adipose tissue wet weight (BATww) and total protein concentration (TPC) of BAT.  相似文献   
867.
头孢克洛缓释片治疗成人急性鼻窦炎临床研究   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 评价头孢克洛缓释片治疗成人急性鼻窦炎的疗效及安全性。方法 62例18-65岁诊断为急性鼻窦炎受试病例,连续服用头孢克洛缓释片(750 mg/次,每日两次,口服)14天,进行多中心的开放式研究。分别在治疗前后对病例进行症状和体征的评估,记录治疗期间发生的不良事件。结果 临床治愈15.5%,好转72.4%,总有效率87.9%(P<0.05)。12.9%的受试病例发生了以胃肠道事件为主的非严重性不良事件。结论 头孢克洛缓释片治疗急性鼻窦炎有良好临床疗效,并具有良好的安全性,可作为口服抗生素的一种有效选择。  相似文献   
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