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排序方式: 共有599条查询结果,搜索用时 62 毫秒
71.
Myocardial contractility and left ventricular function in obese patients with essential hypertension 总被引:2,自引:0,他引:2
G E Garavaglia F H Messerli B D Nunez R E Schmieder E Grossman 《The American journal of cardiology》1988,62(9):594-597
Although the risk of developing congestive heart failure increases in parallel with the degree of obesity, load-dependent indexes of left ventricular function are found to be reduced in patients with morbid obesity only. We used the ratio of end-systolic wall stress to end-systolic volume index, which is load-independent, to assess myocardial contractility in 23 nonobese, 28 mildly obese and 26 moderately obese patients with mild to moderate essential hypertension. Although load-dependent indexes (i.e., ejection fraction, fractional fiber shortening and velocity of circumferential fiber shortening) were similar in the 3 groups, end-systolic wall stress to end-systolic volume index was lower in the moderately obese group (2.63 +/- 0.4, p less than 0.002) and even in the mildly obese group (2.88 +/- 0.8, p less than 0.05) than in the nonobese group (3.27 +/- 0.7). Further, there was a significant inverse relation between end-systolic wall stress to end-systolic volume index and body mass index (r = -0.34, p less than 0.005), diastolic diameter (r = -0.56, p less than 0.001) and left ventricular mass index (r = -0.55, p less than 0.001). Some obese patients have depressed myocardial contractility when compared with lean patients despite well-preserved pump function. 相似文献
72.
Adenylate cyclase and guanylate cyclase activity in normal and leukemic human lymphocytes 总被引:1,自引:0,他引:1
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested. 相似文献
73.
74.
Cardiac status in juvenile borderline hypertension 总被引:2,自引:0,他引:2
W S Culpepper P C Sodt F H Messerli D G Ruschhaupt R A Arcilla 《Annals of internal medicine》1983,98(1):1-7
A prospective M-mode echocardiographic study was done to look for early cardiovascular changes in children prone to hypertension with blood pressures between the 75th and 95th percentiles for age. Average systolic/diastolic pressures in 27 children with borderline hypertension were 137/89 mm Hg compared to 110/68 mm Hg for the 26 controls. Echocardiographic measurements were normalized for comparison using two methods. The borderline hypertensive group mean values were significantly greater than controls for left ventricular wall thickness (p less than 0.05 for method 1; p less than 0.001 for method 2), left ventricular mass (p less than 0.001; p less than 0.005) and left ventricular wall thickness to radius ratio (p less than 0.001, both methods). Echocardiographic estimates of left ventricular function were lower in the hypertensive group. This study suggests that cardiac hypertrophy can be shown by noninvasive means in some children before arterial pressure becomes elevated. To assess the incidence and possible consequences of early target organ changes, more extensive clinical evaluation of borderline hypertension in children is recommended. 相似文献
75.
Sex differences in cardiac adaptation to essential hypertension 总被引:4,自引:0,他引:4
G E Garavaglia F H Messerli R E Schmieder B D Nunez S Oren 《European heart journal》1989,10(12):1110-1114
Left ventricular functional and structural adaptations to mild essential hypertension were assessed by 2D-guided M-mode echocardiography in a population of premenopausal and postmenopausal women (n = 29) who were matched with the same number of men with regard to mean arterial pressure, age and race. Premenopausal women had a thinner posterial wall (P less than 0.05), a smaller left ventricular systolic and diastolic diameter, and a smaller left ventricular mass than men with the same level of arterial pressure. Left ventricular performance indices, ejection fraction, velocity of circumferential fibre shortening, and the ratio of the end-systolic wall stress to the end-systolic volume index (a load-insensitive contractility index) were higher in women than in men. These sex differences were most pronounced before the menopause and tended to disappear thereafter. We conclude that in the presence of the same level of arterial pressure, women have smaller left ventricular dimensions and enhanced ventricular performance compared with men. These differences in cardiac adaptations between the genders may account for the lower risk of cardiovascular morbidity and mortality in premenopausal women with essential hypertension. 相似文献
76.
Messerli FH 《Archives of internal medicine》2003,163(22):2791-2; author reply 2792-3
77.
78.
Renal haemodynamic studies in obesity hypertension 总被引:2,自引:0,他引:2
Previous investigations have reported the systemic haemodynamic characteristics of obese hypertensive patients; however, their renal haemodynamics have not been explored. This report compares the renal and systemic haemodynamic findings in obese and lean normotensive and hypertensive patients. Our results demonstrate that both normotensive and hypertensive obese subjects had an increased renal blood flow, total blood volume and cardiac output, with decreased total peripheral and renal vascular resistances in comparison with lean normotensive and hypertensive patients. Body weight correlated directly and significantly with total blood volume, cardiac output and renal blood flow but indirectly with total peripheral resistance. Therefore, the elevated cardiac output and volume expansion found in obese patients were associated with increased renal perfusion; this increased renal blood flow accounts for the reduced renal vascular resistance in patients with obesity hypertension. Thus, we suggest that this effect of volume expansion in obesity could counteract the opposing effect of active vasoconstriction produced by the hypertensive disease and may account for the difference in prognosis of obese and lean hypertensive patients. 相似文献
79.
I Kobrin W Oigman A Kumar H O Ventura F H Messerli E D Frohlich F G Dunn 《Journal of the American Geriatrics Society》1984,32(12):896-899
Twenty-one elderly patients with essential hypertension, all over 65 years of age, were subjected to automated noninvasive 24-hour blood pressure measurement. Readings were obtained every 7.5 minutes throughout the day. The data were analyzed with respect to: correlation between office and ambulatory pressure measurements; possible differences in the circadian blood pressure pattern; and the existence of hypertensive or atherosclerotic cardiovascular complications. In all patients, the office systolic pressures were significantly higher than the ambulatory daytime pressures; diastolic pressures were similar. At night, two patterns of blood pressure emerged. In one there was a further fall in both systolic and diastolic pressures to normotensive levels, whereas the other pattern revealed no change in diastolic pressure, although systolic pressure increased significantly to similar levels as measured in the office. The prevalence of hypertensive or atherosclerotic cardiovascular complications in the patients with the first pattern was significantly less than in the group of patients with the second pattern (chi square, P less than 0.025). The data reported herein indicate that ambulatory blood pressure monitoring may help in the overall clinical evaluation of elderly patients with hypertension. 相似文献
80.