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991.
OBJECTIVE: Portugal has one of the highest incidences of cerebrovascular disease in Europe. We speculated that this could be due to an early setting of the main cardiovascular risk factors in the Portuguese population. METHODS AND RESULTS: The levels of the main cardiovascular risk factors were assessed in 1001 candidates to a private Health Education Institution (mean age: 19.3+/-3.3 years). Overall, men had a higher body mass index (23.0+/-3.0 vs. 21.5+/-3.0 kg/m2, p<0.001), higher blood pressure levels (124+/-12 and 73+/-7 vs. 116+/-12 and 70+/-7 mm Hg for systolic and diastolic pressure, respectively, p<0.001) and higher triglyceride levels (70+/-41 vs. 59+/-31 mg/dl, p<0.001) than women. Prevalence of obesity, hypertension, smoking and drinking were also higher in men (6%, 15%, 24% and 40% vs. 4%, 4%, 17% and 13% in women, respectively, p<0.01). Conversely, women had higher levels of total cholesterol (174+/-31 vs. 166+/-33 mg/dl, p<0.001), which were due to higher levels of HDL-cholesterol (52+/-1 vs. 45+/-9 mg/dl, p<0.001). Finally, in both genders, obese subjects had significantly higher levels of systolic and diastolic blood pressure, total cholesterol and triglycerides than non-obese. CONCLUSIONS: The prevalence of cardiovascular risk factors is high among young male Portuguese students and preventive measures should be applied, namely regarding obesity.  相似文献   
992.
Results of the pilot study for the Hypertension in the Very Elderly Trial   总被引:14,自引:0,他引:14  
BACKGROUND: The risks and benefits of treating hypertension in individuals older than 80 years are uncertain. A meta-analysis has suggested that a reduction in stroke events of 36% may have to be balanced against a 14% increase in total mortality. OBJECTIVES: To report the results of the pilot study of the Hypertension in the Very Elderly Trial (HYVET), which is in progress to address these issues. METHODS: The HYVET-Pilot was a multicentre international open pilot trial. In 10 European countries, 1283 patients older than 80 years and with a sustained blood pressure of 160-219/90-109 mmHg were allocated randomly to one of three treatments: a diuretic-based regimen (usually bendroflumethiazide; n = 426), an angiotensin-converting enzyme inhibitor regimen (usually lisinopril; n = 431) or no treatment (n = 426). The procedure permitted doses of the drug to be titrated and diltiazem slow-release to be added to active treatment. Target blood pressure was < 150/80 mmHg and mean follow-up was 13 months. RESULTS: In the combined actively treated groups, the reduction in stroke events relative hazard rate (RHR) was 0.47 [95% confidence interval (CI) 0.24 to 0.93] and the reduction in stroke mortality RHR was 0.57 (95% CI 0.25 to 1.32). However, the estimate of total mortality supported the possibility of excess deaths with active treatment (RHR 1.23, 95% CI 0.75 to 2.01). CONCLUSIONS: The preliminary results support the need for the continuing main HYVET trial. It is possible that treatment of 1000 patients for 1 year may reduce stroke events by 19 (nine non-fatal), but may be associated with 20 extra non-stroke deaths.  相似文献   
993.
We performed this prospective cohort study to correlate the findings of left ventricular angiography (LVA) and NOGA left ventricular electromechanical mapping (LVEM) in the evaluation of cardiac wall motion and also to establish standards for wall motion assessment by LVEM. Fifty-five patients (35 men; mean age, 60.4 +/- 11.8 years) eligible for elective left cardiac catheterization underwent LVA and LVEM. Wall motion scores, LV ejection fractions (LVEF), and LV volumes derived from LVA versus LVEM data were compared and analyzed statistically. Receiver operating characteristic (ROC) curves were used to assess the accuracy of LVEM in distinguishing between normal, hypokinetic, and akinetic/dyskinetic wall motion. Mean LVEM procedure time was 37 +/- 11 minutes. The LVEM and LVA findings differed for mean LVEF (55% +/- 13% vs 36% +/- 9%), mean end-systolic volume (56 +/- 13 mL vs 36 +/- 10 mL), and mean end-diastolic volume (174 +/- 104 mL vs 123 +/- 65 mL). Mean wall motion scores (+/- SD) for normokinetic, hypokinetic, and akinetic/dyskinetic segments were 13.9% +/- 5.6%, 8.3% +/- 5.2%, and 3.2% +/- 3.1%, respectively. Cutpoints for differentiating between wall motion types were 12% and 6%. The ROC curves showed LVEM to have a 93% accuracy in differentiating between normokinetic and akinetic/dyskinetic segments and a 73% accuracy between normokinetic and hypokinetic segments. These data suggest that LVEM can differentiate between normal and abnormal cardiac wall motion, although it is more accurate at differentiating between normokinetic and akinetic/dyskinetic motion than between normokinetic and hypokinetic motion.  相似文献   
994.
This study aimed to identify and understand the essence of the anguish of five asthmatic women, patients of the Pneumology Service of a hospital in Porto Alegre, and how they interact with the health professionals. It uses the qualitative methodology, with semi-structured interviews. The content analysis identified: a dependent relationship and an incidence of separation anguish demonstrated by the way the women deal with medication and the caregivers; some of the women's impediments; difficulties to describe the illness and asthma crisis. The separation anxiety and the dependent behavior of the patient must be understood by the caregiver.  相似文献   
995.
Persons undergoing genetic testing for an inherited predisposition to cancer often raise questions about recommendations for follow-up care. Missing from current guidelines is consideration of the role of estrogens for BRCA1/BRCA2 mutation carriers. Potential implications of hormones for risk of cancer and effectiveness of risk-reduction strategies need to be considered in the design of comprehensive guidelines for high-risk women. Patients who are mutation carriers may ask questions about the use of oral contraceptives, hormone replacement, and utility of current screening modalities. Controversy exists, even when considering these issues for the general population, but become more imperative when considering young, unaffected women who carry an inherited genetic mutation making decisions that may have long-term health consequences. Many patients have considered estrogen ablation via prophylactic surgeries as risk-reduction interventions. This article reviews data regarding these issues, makes recommendations based on available information, and offers future perspectives for those identified at high risk for cancer because of genetic predisposition. Although questions remain regarding the potential implications of hormones for risk of cancer and effectiveness of risk-reduction strategies, all information should be considered when educating and caring for such patients.  相似文献   
996.
Mandibular fractures in children: long term results   总被引:1,自引:0,他引:1  
Mandibular fractures in children treated in our department between March 1994 and January 2001 were retrospectively studied. Age, sex, type of fracture, etiology and evolution after treatment, functional mobility and maximal mouth opening were recorded. The population consisted of 19 patients who sustained 30 fractures. The patients ages ranged from 1.5 to 18 years. The mean time of follow up was 28 months. The male to female ratio was 1.7:1. Traffic and bicycle accidents were the main causes of the fractures. The condyle was involved in 16% of the cases, the subcondylar region in 28%. Fractures were multiple in half of the cases. Isolated fractures of the condyloid joint were treated conservatively. For isolated subcondylar fractures, maxillomandibular fixation was the treatment in 40% of the cases. Otherwise, conservative functional treatment was used. Children with a combination of body and condyle fractures were treated by open reduction and maxillomandibular fixation. Neither infection nor retarded facial growth was observed. Only one case of ankylosis of the temporomandibular joint (TMJ) and one case of temporomandibular pain syndrome were recorded. Associated lesions might concern the extremities, the brain and the cervical spine.  相似文献   
997.
Carvalho S  Büki B  Bonfils P  Avan P 《Hearing research》2003,175(1-2):215-225
The rather shallow growth of click-evoked otoacoustic emissions (CEOAE) with click intensity, namely <1 dB/dB, distinguishes genuine CEOAEs from stimulus artifacts, thereby providing the rationale for the popular 'derived nonlinear recording' method. However, other CEOAE nonlinearities regarding phase or envelope dependence on stimulus intensity have been barely acknowledged so far. The present work used CEOAEs from 20 normal ears recorded in response to 50-86 dB peak equivalent SPL clicks. The phases of CEOAE spectral components varied considerably with click intensity (sometimes more than 120 degrees ), mostly in a monotonic manner and in such a way that in the majority of ears, phase lagged with increasing intensity. When present, synchronized spontaneous otoacoustic emissions exhibited the same behavior. In a few instances, conspicuous frequency shifts of CEOAE spectral peaks were seen. In contrast to CEOAE phases, envelopes were almost intensity-invariant. This behavior contrasts with that of basilar membrane motion at the place tuned to the stimulus frequency, as consistently disclosed by several recent publications, i.e., no phase shift and large envelope shift with stimulus intensity. It is thought that the phase invariance of basilar membrane motion implies that whatever they do, outer hair cells cannot alter the resonance frequency of the cochlear partition. If one elaborates along this line of reasoning, the large phase shift of CEOAEs with click intensity implies that CEOAEs at frequency f cannot come from the place tuned to f and that instead, they may be intermodulation distortion products produced by nonlinear interactions between spectral components of the click stimulus over a significant length of the basilar membrane.  相似文献   
998.
We demonstrated that aldose reductase inhibition corrects the impaired microvascular responses to inflammatory mediators in diabetic rats. To study the mechanism involved in the restoring effect of aldose reductase inhibition, we examined the effects of minalrestat, another aldose reductase inhibitor, on the responses of mesenteric microvessels studied in vivo to permeability-increasing agents in diabetic and galactosemic rats. The diabetic group was treated from 3 days after the alloxan injection with minalrestat (10 mg/kg/day) for 30 days and the minalrestat treatment (10 mg/kg/day/7 days) of galactosemic rats started concomitantly with the induction of galactosemia. The mesenteric microvessel reactivity was studied using intravital microscopy and changes in vessel diameters were estimated after the topical application of vasoactive agents. The impaired responses to bradykinin, histamine, and platelet-activating factor of arterioles and venules observed in diabetic and galactosemic rats were completely prevented by minalrestat. Neither diabetes nor galactosemia affected responses to acetylcholine and sodium nitroprusside. Responses to these agents were not modified by aldose reductase inhibition. The restoring effect of minalrestat was reversed by inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester, by blocking K(+) channel with tetraethylammonium but not by cyclooxygenase inhibition with diclofenac. Therefore, we concluded that NO, membrane hyperpolarization, but not cyclooxygenase products are involved in the beneficial effect of minalrestat on the microvascular reactivity in diabetes. Together, these findings led us to suggest that aldose reductase inhibition might ameliorate diabetic complications through the correction of the altered microvascular reactivity by a mechanism that involves NO and membrane hyperpolarization.  相似文献   
999.
OBJECTIVE: The aims of this study were to evaluate inflammatory cells, the profile of inflammatory mediators in nasal lavage (NL), and the involvement of the paranasal mucosa in atopic infants with no symptoms of sinusitis. METHODS: 48 atopic patients with allergic rhinitis (AR), and 33/48 patients with asthma were studied; the control group consisted of 13 nonatopic children. Those individuals with acute, chronic or recurrent sinusitis were excluded. The involvement of the paranasal mucosa was assessed by coronal computed tomography (CT) and graded by a standard protocol (0-30). A CT score greater than or equal to 12 indicated extensive involvement. Nasal lavage was used to quantify total and differential nasal cell counts. An aliquot of the supernatant was used for determining inflammatory mediators: interleukin-8 (IL-8), myeloperoxidase (MPO), and eosinophil cationic protein (ECP). Albumin was used as a marker for increased vascular permeability. These measurements were performed on all of the atopic patients and in 6/13 patients in the control group. The three groups were submitted to spirometry and complete blood cell count. RESULTS: Extensive involvement of the paranasal mucosa was observed in 7/33 (21%) of asthmatic patients (Group I) and 2/15 (13%) of those with allergic rhinitis (Group II). The highest CT score in the control group (Group III) was 7. Total cell and eosinophil count/ml and albumin concentration in nasal fluid were higher in asthmatic patients whose CT score was greater than 12. Interleukin-8 concentration, number of neutrophils and epithelial cells/ml in nasal fluid were similar in the three groups. A positive correlation between CT score, peripheral blood eosinophilia, number of eosinophils/ml and eosinophil cationic protein concentration was found in the nasal fluid of atopic children (n=48). There was an association between number of neutrophils and titers of interleukin-8 and myeloperoxidase, and between interleukin-8 and eosinophil count. CONCLUSIONS: in asthmatic patients with no symptoms of sinusitis, the extensive involvement of the paranasal mucosa is associated with blood and nasal lavage eosinophilia and cellular activation. Neutrophil infiltration and activation were not related to increased involvement of the paranasal mucosa.  相似文献   
1000.
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