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11.
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   
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The following work deals with ibuprofen-loaded ethylcellulose microspheres. The drug exists either in a state of molecular dispersion or in crystalline form, depending on the encapsulation ratio. The in vitro release profiles have been studied and the Higuchi model applied to the experimental results. With an appropriate treatment of the results, it has been shown that the surface crystals responsible for the observed burst effect are really encapsulated by the polymer. The calculation of the tortuosity factor clearly shows that the release kinetics are controlled by the hydrophobicity of ethylcellulose and the geometry of the porous volume resulting from the dissolution of ibuprofen crystals. It thus appears that crystals are probably differently distributed in the matrix depending on the microsphere size.  相似文献   
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The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present.  相似文献   
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Gliomatosis peritonei, the miliary implants of mature glial tissues on the peritoneum or omentum, is a rare complication of solid ovarian teratoma. Our case is reported and 38 previously reported cases are reviewed. The grade of the primary tumors varied from grade 0 to grade 3. Only five cases were composed entirely of mature tissues. Five of the 39 patients died. Despite of varied therapy, the rest of the patients were alive from 3 months to 38 years later. Inspite of intraperitoneal implants, the prognosis in patients with these tumors is good, irrespective of the mode of therapy. On the basis of this study, we recommended a conservative therapy for the primary tumor and therapy for the implants is not required.  相似文献   
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The purpose of this study was to test the hypothesis that specific cytokines are involved in the initiation and evolution of the fibrotic process in adhesive capsulitis of the shoulder. After approval from the Institutional Review Board, biopsies of shoulder capsule and synovium were collected during shoulder arthroscopy from 19 patients with adhesive capsulitis, 14 patients with nonspecific synovitis and no fibrosis or clinical evidence of adhesive capsulitis, and seven patients undergoing surgery for another pathology who had a normal capsule and synovium. Immunohistochemical localization with monoclonal antibodies to transforming growth factor-β and its receptor, platelet-derived growth factor and its receptor, basic fibroblast growth factor, interleukin-1β, tumor necrosis factor-α, and hepatocyte growth factor was performed using standard immunoperoxidase techniques. The frequency of cytokine staining was correlated with the clinical diagnosis Synovial cells, fibroblasts, T-cells, and B-cells were identified with specific antibodies, and newly synthesized matrix was examined for type-I and type-III collagen by immunohistochemical staining. The predominant cell types present were synovial cells and fibroblasts. Staining for type-III collagen in adhesive capsulitis tissues indicated new deposition of collagen in the capsule. There was staining for transforming growth factor-β and its receptor, platelet-derived growth factor and its receptor, interleukin-1β, and tumor necrosis factor-α in adhesive capsulitis and nonspecific synovitis tissues, compared with minimal staining in normal capsule. Staining was more frequent in snovial cells than in capsular cells. The frequency of cell and matrix staining for transforming growth factor-β, platelet-derived growth factor, and hepatocyte growth factor was greater in adhesive capsulitis tissues than in those from patients with nonspecific synovitis. No difference in the frequency of staining between primary (idiopathic) and secondary adhesive capsulitis was found. The results of this study indicate that adhesive/capsulitis involves both synovial hyperplasia and capsular fibrosis. Cytokines such as transforming growth factor-β and platelet-derived growth factor may be involved in the inflammatory and fibrotic processes in adhesive capsulitis. Matrix-bound transforming growth factor-β may act as a persistent stimulus, resulting in capsular fibrosis. Understanding the basic pathophysiology of adhesive capsulitis is an important step in the development of clinically useful antifibrotic agents that may serve as novel treatments for patients with this condition.  相似文献   
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A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p less than 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p less than 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients. Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography.  相似文献   
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This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states.  相似文献   
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