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81.
VG Hardcastle 《Canadian Metallurgical Quarterly》1996,5(3):359-367
BACKGROUND: Although it has become clear that habitual exercise in older individuals can partially offset age-associated cardiovascular declines, it is not known whether the beneficial effects of exercise training in older individuals depend on their prior fitness level. METHODS AND RESULTS: Ten sedentary men (S), age 60.0 +/- 1.6 years (mean +/- SEM), who were carefully screened to exclude cardiac disease underwent exercise training for 24 to 32 weeks, and eight age-matched endurance-trained men (ET) stopped their exercise training for 12 weeks. All underwent treadmill exercise and rest and maximal cycle exercise upright gated blood pool scans at baseline and after the lifestyle intervention. Before the intervention, the treadmill maximum rate of oxygen consumption (Vo2max) was 49.9 +/- 1.9 and 32.1 +/- 1.4 mL.kg-1.min-1 in ET and S, respectively. During upright cycle exercise at exhaustion, although heart rate did not differ between groups, cardiac index, stroke volume index, ejection fraction, and left ventricular contractility index (systolic blood pressure/end-systolic volume index) all were significantly higher, and end-systolic volume index, diastolic blood pressure, and total systemic vascular resistance all were significantly lower in ET versus S. After the partial deconditioning of ET men, Vo2max fell to 42 +/- 2.2 mL.kg-1.min-1, and training of S increased Vo2max to 36.2 +/- 1.6 mL.kg-1.min-1. Training of S had effects on cardiovascular function that were similar in magnitude but directionally opposite those of detraining ET. All initial differences in cardiovascular performance at peak work rate between S and ET were abolished with the intervention. Across the broad range of fitness levels encountered before and after change in training status (Vo2max of 26 to 58 mL.kg-1.min-1), cardiac index, stroke volume index, end-systolic volume index, ejection fraction, and the left ventricular contractility index were all linearly correlated with Vo2max. CONCLUSIONS: Exercise training or detraining of older men results in changes in left ventricular performance that are qualitatively and quantitatively similar, regardless of the initial level of fitness before the intervention. 相似文献
82.
VG Sharov A Goussev M Lesch S Goldstein HN Sabbah 《Canadian Metallurgical Quarterly》1998,30(9):1757-1762
Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria that include hyperplasia, reduced organelle size and compromised structural integrity. In the present study, we examined mitochondrial respiration in myocardium of 10 normal dogs and 10 dogs with chronic HF (LV ejection fraction 24+/-2%) produced by intracoronary micro-embolizations. Mitochondrial respiratory rates were determined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles. Basal respiratory rate (VO), respiratory rate after addition of substrates, glutamate and malate (VSUB) and state 3 respiratory rate (VADP, after addition of ADP), were measured in tissue samples from the subendocardial and subepicardial LV free wall, interventricular septum and right-ventricular free wall. No differences were observed in basal respiratory rates between normal and HF tissue, while VSUB was significantly lower in HF compared to normal. VADP was 50-60% lower in HF compared to normal tissue (P<0.001). The results indicate abnormal mitochondrial respiratory activity in myocardium of dogs with chronic HF. These findings support the concept of low myocardial energy production in HF that can contribute to the global cardiac dysfunction. 相似文献
83.
Clinical study of 172 patients treated in the Burdenko Military Hospital for subacute infectious endocarditis in 1980-1996 compared with 192 cases in 1950-1979. Contemporary course of the disease is attended by a few symptoms, primordiality and single-valve affection. On the grounds of antibiotics sensitivity of the most prevalent infection agents discovered in 1996, the article develops some schemes of antibacterial therapy for Streptococcus, Enterococcus and staphylococcal etiology of disease. Rational antibiotic therapy together with surgery measures reduced lethality to 14.3% for Streptococcus endocarditis, to 16.7%--for Enterococcus and to 34.4%--for Staphylococcus. 相似文献
84.
VP Barkhatova ZA Suslina VG Ionova IA Chudakova OE Mel''kina MM Tanashian OIu Rebrova 《Canadian Metallurgical Quarterly》1998,98(8):34-38
Contents of lipids (cholesterol CS, triglycerides) as well as levels of CS of lipoproteins of different density and of apolipoproteins A1 and B were measured in blood serum of 31 patients in different periods after of ischemic stroke. The majority of the indices studied were significantly decreased in men in acute periods of the stroke, especially in 8-21 days after the stroke development. Meanwhile, the levels of lipids, CS lipoproteins of both low and very low densities were increased later. Contents of CS of antiatherogenic lipoproteins of high density (HDLP) was low in different periods after the development of disorders of cerebral circulation. This confirms the concept that low level of HDLP is one of the risk factors of ischemic stroke. Decrease of the levels of both lipids and CS of lipoproteins of different density was more pronounced in patients with more severe atherosclerotic damages of the main cerebral arteries. Disorders of metabolism of lipoproteins in ischemic disorders of cerebral circulation are discussed with reference to literary data taking into consideration their heterogeneity. Genetically determined pathology of certain apolipoproteins plays a key role factor in the development of early atherosclerosis and in the elucidation of biochemical markers of the primary damages of cerebral vessels. 相似文献
85.
I Rajman GY Lip R Cramb SR Maxwell J Zarifis DG Beevers MJ Kendall 《Canadian Metallurgical Quarterly》1996,89(10):771-778
In a prospective longitudinal study in 17 women, we investigated the effects of surgical menopause and subsequent oestrogen-only hormone replacement therapy (HRT) on plasma concentrations of total cholesterol, HDL cholesterol, LDL cholesterol, triglyceride and LDL subfractions profile. Plasma LDL is a heterogeneous population of particles of varying size, density and chemical composition. The predominance of small LDL particles is a newly-recognized risk factor for coronary artery disease. The LDL score is used to describe LDL subfractions profile and the greater the score, the higher the proportion of small LDL particles. Six weeks after hysterectomy and bilateral oopherectomy, total cholesterol and triglyceride concentrations were significantly increased (p < 0.01) as well as the LDL score (p < 0.05). After 6 weeks of oestrogen-only HRT, total cholesterol concentration was significantly lower and HDL cholesterol concentration significantly higher than before the treatment (p < 0.05). At the same time, mean LDL score significantly increased and in none of the women did LDL subfractions profile change favourably. 相似文献
86.
VG Karpov 《Canadian Metallurgical Quarterly》1994,50(24):18106-18112
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89.
KG Karageuzyan ES Sekoyan AT Karagyan NR Pogosyan GG Manucharyan AE Sekoyan AY Tunyan VG Boyajyan MK Karageuzyan 《Canadian Metallurgical Quarterly》1998,63(10):1226-1232
The effect of low-energy infrared laser irradiation on the phospholipid pool, lipid peroxidation, and superoxide dismutase activity in the brain of white rats was studied in experimental ischemia, reperfusion, and acute edema. These models are characterized by oxidative stress; the contents of tri- and diphosphoinositides and sphingomyelins were lowered, whereas the levels of phosphatidylserine and phosphatidylethanolamine did not change, and the amount of phosphatidylcholine was increased. In acute brain edema, the contents of hydroperoxides and malonic dialdehyde in enzymatic and nonenzymic lipid peroxidation systems were increased in mitochondrial and microsomal fractions and the level of arachidonic acid was significantly elevated. Infrared laser irradiation contributes to the correction of the changes in the phospholipid pool; laser irradiation lowered the increased levels of hydroperoxides and malonic dialdehyde and elevated superoxide dismutase activity in the brain during ischemia, reperfusion, and acute edema of the brain. The data suggest that low-energy infrared laser irradiation has certain neuroprotective activity in various types of oxidative stress including ischemia, reperfusion, and acute edema of the brain. 相似文献
90.