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21.
BACKGROUND: Aerobic exercise training has been associated with beneficial effects on the cardiovascular system, improving arterial compliance, possibly related to a positive impact on the endothelium. The effects of competitive aerobic exercise are not so well documented. This prompted us to evaluate the possible modulation of arterial properties in a group of athletes and their response to the aging process. METHODS: 423 healthy males were enrolled in a cross-sectional study, 212 of whom were competitive athletes and 211 were controls. All underwent carotid-femoral pulse wave velocity (PWV) evaluation, and casual blood pressure and other relevant anthropometric data were evaluated. RESULTS: To control the effects of age, each group was divided into two subgroups with an age cut-point of 20 years. PWV was 6.3 +/- 0.9 m/s (athletes) vs. 7.0 +/- 1.0 m/s (controls) for ages <20 years, and 7.6 +/- 1.2 m/s (athletes) vs. 8.1 +/- 0.9 m/s (controls) for ages >20 years, with statistically significant differences in both comparisons. A linear regression model with logarithmic tendency analysis with age as the independent determinant of PWV revealed a different progression of age-related deterioration of aortic compliance between the two groups (athletes and controls). CONCLUSIONS: Our data documented better compliance indices in competition athletes compared with controls, which may reflect optimization of endothelial function. This improvement was age-dependent, being less pronounced as the athletes grow older, which could be due partially to sustained stretching effects on the arterial walls in long-term competitors.  相似文献   
22.
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events.  相似文献   
23.
We describe the case of a pregnant woman with idiopathic pulmonary arterial hypertension, a responder in right heart catheterization, followed since the first trimester in outpatient consultations, admitted to hospital at 23 weeks gestation. She was treated with inhaled iloprost until delivery (at 34 weeks gestation) and continuous infusion of iloprost throughout the perioperative period and following days. This line of therapy has proved efficacious in previous cases. The authors present echocardiographic images that document acute changes in ventricular synchrony during inhalation of iloprost.  相似文献   
24.
BACKGROUND: There are numerous studies that individually evaluate the efficacy/effectiveness and toxicity of drugs in the systemic treatment of psoriasis. On the contrary, we can hardly find studies that compare each other. OBJECTIVE: To evaluate and compare the effectiveness and toxicity of mycophenolate mofetil and cyclosporin in chronic plaque psoriasis through a prospective, sequential, cross-over, non-randomized, two-phase, open-label study. PATIENTS/METHODS: Eight patients (five women and three men; mean age 57, range 35-78) with moderate-to-severe chronic plaque psoriasis were included in the study. They were treated with oral mycophenolate mofetil (30 mg/kg/day) over a period of 16 weeks. Following a variable washout period and after a new outbreak of the disease, oral cyclosporin was introduced at a dose of 4 mg/kg/day. During both treatment regimens, follow-up visits were performed at 3, 8 and 16 weeks. RESULTS: In both groups, the PASI started to decrease once treatment was begun. Cyclosporin was faster and statistically a lot more effective than mycophenolate mofetil, reaching a higher number of complete remissions and better percentages of PASI improvement from baseline (45.7%, 60.2% and 60.5% at 3, 8 and 16 weeks respectively for mycophenolate mofetil, and 89.7%, 95.3% and 95.3% respectively at the same intervals for cyclosporin). Cyclosporin was also more predictable in its action as the percentage of improvement along the follow-up visits had a much wider range for mycophenolate mofetil. Overall, the tolerability of both drugs was good. None of the patients had to discontinue treatment because of an adverse event. Two patients treated with cyclosporin showed increased plasma levels of creatinine. CONCLUSIONS: Cyclosporin is more effective, fast, and predictable in its effect than mycophenolate mofetil to control moderate-to-severe chronic plaque psoriasis. Both drugs are well tolerated in short courses of treatment.  相似文献   
25.
A precise and simple method for the determination of (234)Th activity by Cerenkov counting is described. A calibrated natural uranium solution (having (234m)Pa and (238)U in secular equilibrium) in 0.1M HNO(3) is used to construct the calibration curve. Because (231)Th (a beta-emitting nuclide present in the decay chain of (235)U) contribution to Cerenkov counting is experimentally proved to be negligible only in the case of low enriched uranium samples, simple calculations are needed to accomplish the activity determination.  相似文献   
26.
27.
A 76-year-old woman with an inferior wall myocardial infarction, with right ventricular involvement, developed severe arterial hypoxemia with neurological involvement. Pulmonary edema or embolism and chronic obstructive pulmonary disease were ruled-out, and a right-to-left shunt was demonstrated by contrast echocardiography at the level of the foramen ovale. After inotropic support and oxygen supplementation, the patient recovered, although with significant neurological sequelae. No focal lesions were detected in the central nervous system by computerized tomography. Hypoxemia improved, coinciding with the disappearance of right-to-left shunt by contrast echocardiography.  相似文献   
28.
We studied the hepatic handling of bromosulfophthalein in healthy rabbits with hepatic coccidiosis 28 days after an experimental infection with sporulated oocysts of Eimeria stiedai, an experimental model of liver disease histopathologically resembling primary biliary cirrhosis in man. A pharmacokinetic study of the results was performed following a multicompartmental model with 7 transfer constants to describe the physiological disposition of the dye. The study showed that the plasma disappearance, distribution volume (Vi), hepatic biotransformation and the biliary and urinary elimination of conjugated (BSPc) and unconjugated (BSPu) bromosulfophthalein were markedly altered. Whereas Vi and urinary excretion of the dye were significantly increased, the hepatic clearance, biotransformation and biliary excretion of BSPc and BSPu were drastically reduced in infected rabbits. Satisfactory agreement was obtained between the experimental and estimated data, particularly those relating to biotransformation clearance and biliary and urinary excretion of the dye. These results demonstrate that severe liver disease in rabbits with histopathological liver alterations resembling several hepatic dysfunctions in man markedly reduce hepatic uptake, metabolism and biliary excretion of a xenobiotic such as BSP.  相似文献   
29.
Based on a series of 220 cases of reconstruction (63 cases) or correction (67 cases) of the nipple-areolar complex and various extramammary procedures (tattoo scar revision, lips, eyebrows, eyelashes) (90 cases), the authors present their 2-year experience of medical dermography in a cancer centre. Dermography allows breast reconstruction to be completed in a large number of patients who had initially refused to complete their reconstruction. This minimally aggressive outpatient technique which reconstitutes the areolo-nipple complex with sufficient quality, is now part of reconstruction protocols and is gradually replacing surgical techniques.  相似文献   
30.
Interleukin-1 (IL-1) is a cytokine produced by the macrophage-monocyte system that has important effects on immunological responses and inflammatory reactions. Several clinical studies have shown that severe protein energy malnutrition adversely effects cell-mediated immune responses and the functional state of macrophages. The objective of this study was to analyse IL-1 production by adherent cells stimulated in vitro with lipopolysaccharide B (LPS) from patients with alcoholic cirrhosis of the liver and its possible relationship with nutritional states. Forty-five patients with alcoholic cirrhosis and 28 healthy donors were investigated. A combined index of nine anthropometric and biochemical parameters was used to evaluate nutritional status of cirrhotic patients, allowing a distinction to be made between those patients with acceptable nutrition (group I: 40%), those with slight malnutrition (group II: 37.7%), and those with severe malnutrition (group III: 22.3%). IL-1 activity was significantly lower in the cirrhosis patients than in the controls (P less than 0.001). This activity also was significantly lower in samples obtained from cirrhotics with severe malnutrition than in those with acceptable nutrition (P less than 0.05); the combined index and the sole anthropometric index gave the same results, suggesting that malnutrition may play a role in the immunoregulatory disturbances in the pathogenesis of alcoholic liver disease.  相似文献   
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