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High-density lipoprotein cholesterol and longevity   总被引:1,自引:0,他引:1  
Serum total cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides were studied in three groups: (1) 85 healthy subjects aged 85-89 years, (2) 62 patients without coronary artery disease aged 38-62 years, and (3) 323 patients aged 32-69 years with triple-vessel disease diagnosed by coronary angiography. The mean values for total cholesterol were significantly higher in patients with triple-vessel disease than in those without coronary artery disease and in the elderly. Total cholesterol was over 6.5 mmol/l in 32% of the elderly, in 31% of patients without coronary artery disease and in 42% of patients with triple-vessel disease, but these differences were not significant. HDL-cholesterol and the ratio of HDL/total cholesterol were significantly higher in the elderly than in the patients without coronary artery disease and patients with triple-vessel disease. Serum HDL-cholesterol was over 1.0 mmol/l in 92% of the elderly, in 69% of patients without coronary artery disease and in 46% of patients with triple-vessel disease, the differences being significant between all groups.  相似文献   
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Pharmaceutical Research - Beagle dogs are used to study oral pharmacokinetics and guide development of drug formulations for human use. Since mechanistic insight into species differences is needed...  相似文献   
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BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality.  相似文献   
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To study the mechanisms of low density lipoprotein (LDL) cholesterol lowering by peroral and transdermal estrogen replacement therapy (ERT), 79 hysterectomized postmenopausal women aged 48 to 62 years were randomized in a double-blind double-dummy trial to receive either peroral estradiol valerate (2 mg/d) or transdermal estradiol gel (1 mg/d) for 6 months. Plasma LDL cholesterol decreased from 4. 19+/-0.83 (mean+/-SD) to 3.39+/-0.78 mmol/L (P<0.001) in the peroral group and from 4.11+/-0.86 to 3.72+/-0.78 mmol/L (P<0.001) in the transdermal estrogen group. Peroral estrogen did, but transdermal treatment did not, enhance the fractional catabolic rate (FCR) and production of LDL apolipoprotein B (apoB). However, the decrease of LDL cholesterol was related to an increase in FCR for LDL apoB on both peroral and transdermal ERT (r=-0.645, P<0.001 and r=-0.627, P<0.001, respectively). These changes were associated with changes in the serum estrogen level. Both therapies reduced absorption of dietary cholesterol by 6% to 10% (P<0.05). The effects of estrogen were not modified by the polymorphisms of apoE and apoB or cholesterol 7alpha-hydroxylase. In conclusion, the ERT-induced LDL cholesterol-lowering effect is related to changes in estrogen level, which presumably enhance LDL receptor activity, which is manifested as an increase in FCR for LDL apoB. The small decrease in the absorption efficiency of dietary cholesterol does not seem to contribute largely to the cholesterol lowering on either transdermal or peroral ERT.  相似文献   
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Postural sway behavior while standing and during and after an unexpected disturbance of balance was examined in men aged 31 to 35, 51 to 55, and 71 to 75 years. The groups studied were random samples of men living in the town of Jyv?skyl? in 1981. Postural sway while standing was more pronounced in the older age groups, whereas after a disturbance of balance postural sway was nearly the same in all age groups. The functioning of the postural control system was correlated with the vibratory threshold on the ankles, grip strength, as well as with aerobic and anaerobic capacity within the age groups. Further, in the youngest age group the functioning of the postural control system was poorer among those who had been subject to noise at their work. The correlation between health status and postural sway was negligible. The results may indicate the partly parallel and similar effects of aging, poor physical fitness, and harmful environmental factors on the functioning of the postural control system.  相似文献   
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