972 resultados para Normalized difference vegetation index (NDVI)
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OBJECTIVE: To assess the relation between coronary artery disease and the calcification index on helical computed tomography. METHOD: We studied 22 patients (ages ranging from 40 to 70 years) who underwent coronary angiography because of chest pain suggestive of angina pectoris. Findings on coronary angiography were classified as follows: significant obstructive disease (stenosis > or = 50%), nonobstructive disease (stenosis <50%), and no disease. With no previous knowledge of the results of the coronary angiography and within 7 days, helical computed tomography of the chest was performed. Then, data of the coronary angiography were correlated with the calcification index obtained by helical computed tomography. RESULTS: The sensitivity of helical computed tomography to the presence of significant obstructive lesions on coronary angiography was 87.5%, specificity was 100%, and negative and positive predictive values were 75% and 100%, respectively. The mean calcification index was greater in patients with severe coronary lesions, mainly when involvement of 2 or 3 vessels occurred, than that in patients with no coronary artery disease or with nonobstructive coronary artery lesions (p<0.05). CONCLUSION: Helical computed tomography is an effective method for detecting and quantifying coronary artery calcification, and it has proved to be sensitive to and specific for the noninvasive diagnosis of coronary artery stenosis.
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O presente estudo pretende verificar se existe uma correlação entre consciência morfológica e desempenho em leitura e escrita (mais precisamente, na componente de leitura) em crianças com e sem dificuldades ou perturbação de leitura e escrita. Para cumprir este objetivo, aplicou-se, numa amostra de crianças falantes de português europeu, dois instrumentos de avaliação: o “Teste de Idade de Leitura” e uma Prova de Consciência Morfológica, especificamente criada para o efeito. O grupo experimental (GE) inclui crianças com diagnóstico de dificuldades ou perturbação de leitura e escrita; o grupo de controlo (GC) não. Após a análise dos dados, conclui-se que existe uma diferença estatisticamente significativa entre os grupos de crianças em estudo, uma vez que o GC revela um desempenho superior ao GE em ambas as provas aplicadas. Os resultados obtidos demonstram ainda uma correlação estatisticamente significativa entre o desempenho das crianças no domínio de leitura e o desempenho das crianças ao nível da consciência morfológica. A correlação mostra-se consideravelmente mais forte no GE do que no GC. Deste modo, conclui-se que a estimulação da consciência morfológica pode efetivamente facilitar e auxiliar o desenvolvimento da aprendizagem leitora em crianças, sobretudo em crianças com dificuldades nestes domínios.
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OBJECTIVE: To compare sleepiness scores of the Epworth scale in patients with different levels of arterial pressure when undergoing outpatient monitoring within the context of clinical evaluation. METHODS: A total of 157 patients selected for outpatient monitoring of arterial pressure during hypertension evaluation were divided into 3 groups: group 1 - normotensive; group 2 - hypertensive; group 3 - resistant hypertensive. For analysis, values > or = 11 were considered as associated with respiratory disturbances during sleep. RESULTS: Seventeen (10.8%) patients in group 1, 112 (71.3%) in group 2, and 28 (17.8%) in group 3, which was composed of aged, more severely hypertensive individuals, were analyzed. Groups were similar relative to sex and body mass index, but different in relation to systolic and diastolic pressure levels and age. Despite an absolute difference, no statistically significant difference occurred between Epworth scores and in the proportion of patients with values > or = 11 (5.9% vs. 18.8% vs. 212.4%; P=0.37). Despite the positive association between degree of sleepiness measured with the scale and the severity of the hypertension, no statistical significance occurred following control by age (p=0.18). CONCLUSION: A positive correlation exists between degree of sleepiness and hypertension severity. The absence of a statistical significance shown in the present study could be due to a beta type of error. Instruments that render this complaint into an objective finding could help in the pursuit of an investigation of respiratory disturbances during sleep in more severely hypertensive patients, and should therefore be studied better.
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OBJECTIVE: To assess the benefit resulting from the use of abciximab associated with primary angioplasty. The following parameters were analyzed in-hospital, at 30 days, and 6 months: (a) flow in the culprit artery; (b) ventricular function; (c) combined outcome of death, acute myocardial infarction, and aditional revascularization. METHODS: From November 1997 to June 1999, a longitudinal nonrandomized study with historical data of 137 patients with acute myocardial infarction within the first 12 hours. Patients undergoing primary angioplasty and were divided into 2 groups: those receiving (A) abciximab (26) or (B) conventional therapy (111). TIMI flow and regional ventricular function estimated by the standard deviation (SD)/chordis index were analyzed. RESULTS: At the end of angioplasty, TIMI 3 flow was observed in 76.9% and 83.8% of the patients in groups A and B, respectively (P=0.58). In the reevaluation, patients with TIMI flow <3 showed a 100% improvement in group A and a 33% in group B (P<0.0001). A significant improvement (P<0.0001) in regional ventricular function, by SD/chordis index, occurred in each group; no significant difference between groups however, was observed (29.9% x 20.2%; P=0.58). A nonsignificant reduction in the combined outcome in the in-hospital phase (3.85% A x 9.0% B; P=0.34) and on the 30th day (4.0% x 12.0%; P=0.22) was observed in group A. CONCLUSION: Abciximab improved blood flow. Primary angioplasty improved regional ventricular function independent of antithrombotic therapy. Abciximab showed a trend toward reducing the combined outcome in the in-hospital phase and on the 30th day.
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PURPOSE: To evaluate left ventricular mass (LVM) index in hypertensive and normotensive obese individuals. METHODS: Using M mode echocardiography, 544 essential hypertensive and 106 normotensive patients were evaluated, and LVM was indexed for body surface area (LVM/BSA) and for height² (LVM/h²). The 2 indexes were then compared in both populations, in subgroups stratified according to body mass index (BMI): <27; 27-30; > or = 30kg/m². RESULTS: The BSA index does not allow identification of significant differences between BMI subgroups. Indexing by height² provides significantly increased values for high BMI subgroups in normotensive and hypertensive populations. CONCLUSION: Left ventricular hypertrophy (LVH) has been underestimated in the obese with the use of LVM/BSA because this index considers obesity as a physiological variable. Indexing by height² allows differences between BMI subgroups to become apparent and seems to be more appropriate for detecting LVH in obese populations.
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OBJECTVE: To objectively and critically assess body mass index and to propose alternatives for relating body weight and height that are evidence-based and that eliminate or reduce the limitations of the body mass index. METHODS: To analyze the relations involving weight and height, we used 2 databases as follows: 1) children and adolescents from Brazil, the United States, and Switzerland; and 2) 538 university students. We performed mathematical simulations with height data ranging from 115 to 190 cm and weight data ranging from 25 to 105 kg. We selected 3 methods to analyze the relation of weight and height as follows: body mass index - weight (kg)/height (m²); reciprocal of the ponderal index - height (cm)/weight1/3 (kg); and ectomorphy. Using the normal range from 20 to 25 kg/m² for the body mass index in the reference height of 170 cm, we identified the corresponding ranges of 41 to 44 cm/kg1/3 for the reciprocal of the ponderal index, and of 1.45 to 3.60 for ectomorphy. RESULTS: The mathematical simulations showed a strong association among the 3 methods with an absolute concordance to a height of 170 cm, but with a tendency towards discrepancy in the normal ranges, which had already been observed for the heights of 165 and 175 cm. This made the direct convertibility between the indices unfeasible. The reciprocal of the ponderal index and ectomorphy with their cut points comprised a larger age range in children and adolescents and a wider and more central range in the university students, both for the reported (current) and desired weights. CONCLUSION: The reciprocal of the ponderal index and ectomorphy are stronger and are more mathematically logical than body mass index; in addition, they may be applied with the same cut points for normal from the age of 5 ½ years on.
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OBJECTIVE - To determine the prevalence of hyperhomocystinemia in patients with acute ischemic syndrome of the unstable angina type. METHODS - We prospectively studied 46 patients (24 females) with unstable angina and 46 control patients (19 males), paired by sex and age, blinded to the laboratory data. Details of diets, smoking habits, medication used, body mass index, and the presence of hypertension and diabetes were recorded, as were plasma lipid and glucose levels, C-reactive protein, and lipoperoxidation in all participants. Patients with renal disease were excluded. Plasma homocysteine was estimated using high-pressure liquid chromatography. RESULTS - Plasma homocysteine levels were significantly higher in the group of patients with unstable angina (12.7±6.7 µmol/L) than in the control group (8.7±4.4 µmol/L) (p<0.05). Among males, homocystinemia was higher in the group with unstable angina than in the control group, but this difference was not statistically significant (14.1±5.9 µmol/L versus 11.9±4.2 µmol/L). Among females, however, a statistically significant difference was observed between the 2 groups: 11.0±7.4 µmol/L versus 6.4±2.9 µmol/L (p<0.05) in the unstable angina and control groups, respectively. Approximately 24% of the patients had unstable angina at homocysteine levels above 15 µmol/L. CONCLUSION - High homocysteine levels seem to be a relevant prevalent factor in the population with unstable angina, particularly among females.
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OBJECTIVE: To compare the accuracy of 4 different indices of cardiac risk currently used for predicting perioperative cardiac complications. METHODS: We studied 119 patients at a university-affiliated hospital whose cardiac assessment had been required for noncardiac surgery. Predictive factors of high risk for perioperative cardiac complications were assessed through clinical history and physical examination, and the patients were followed up after surgery until the 4th postoperative day to assess the occurrence of cardiac events. All patients were classified according to 4 indices of cardiac risk: the Goldman risk-factor index, Detsky modified risk index, Larsen index, and the American Society of Anesthesiologists' physical status classification and their compared accuracies, examining the areas under their respective receiver operating characteristic (ROC) curves. RESULTS: Cardiac complications occurred in 16% of the patients. The areas under the ROC curves were equal for the Goldman risk-factor index, the Larsen index, and the American Society of Anesthesiologists' physical status classification: 0.48 (SEM ± 0.03). For the Detsky index, the value found was 0.38 (SEM ± 0.03). This difference in the values was not statistically significant. CONCLUSION: The cardiac risk indices currently used did not show a better accuracy than that obtained randomly. None of the indices proved to be significantly better than the others. Studies to improve our ability to predict such complications are still required.
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OBJECTIVE: To analyze parameters of respiratory system mechanics and oxygenation and cardiovascular alterations involved in weaning tracheostomized patients from long-term mechanical ventilation after cardiac surgery. METHODS: We studied 45 patients in their postoperative period of cardiac surgery, who required long-term mechanical ventilation for more than 10 days and had to undergo tracheostomy due to unsuccessful weaning from mechanical ventilation. The parameters of respiratory system mechanics, oxigenation and the following factors were analyzed: type of surgical procedure, presence of cardiac dysfunction, time of extracorporeal circulation, and presence of neurologic lesions. RESULTS: Of the 45 patients studied, successful weaning from mechanical ventilation was achieved in 22 patients, while the procedure was unsuccessful in 23 patients. No statistically significant difference was observed between the groups in regard to static pulmonary compliance (p=0.23), airway resistance (p=0.21), and the dead space/tidal volume ratio (p=0.54). No difference was also observed in regard to the variables PaO2/FiO2 ratio (p=0.86), rapid and superficial respiration index (p=0.48), and carbon dioxide arterial pressure (p=0.86). Cardiac dysfunction and time of extracorporeal circulation showed a significant difference. CONCLUSION: Data on respiratory system mechanics and oxygenation were not parameters for assessing the success or failure. Cardiac dysfunction and time of cardiopulmonary bypass, however, significantly interfered with the success in weaning patients from mechanical ventilation.
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OBJECTIVE: To compare the lipid profiles and coronary heart disease risks of 2 Brazilian Amazonian populations as follows: a riverside population (village of Vigia) and an urban population (city of Belém in the state of Pará). METHODS: Fifty individuals controlled for age and sex were assessed in each region, and the major risk factors for coronary heart disease were analyzed. RESULTS: According to the National Cholesterol Education Program (NCEP III) and using the Framingham score, both populations had the same absolute risk of events (Vigia = 5.4 ± 1 vs Belém = 5.7 ± 1), although the population of Vigia had a lower consumption of saturated fat (P<0.0001), a greater consumption of mono- and polyunsaturated fat (P<0.03), in addition to lower values for body mass index (25.4± 0.6 vs 27.6 ± 0.7 kg/m², P<0.02), of biceps skin fold (18.6 ± 1.1 vs 27.5 ± 1.3 mm, P<0.0001), of triceps skin fold (28.7 ± 1.2 vs 37.3 ± 1.7 mm, P<0.002), and of total cholesterol (205 ± 5 vs 223 ± 6 mg/dL, P< 0.03) and triglycerides (119 ± 9 vs 177 ± 18 mg/dL, P<0.005). Both populations did not differ in regard to HDL-C (46 ± 1 vs 46 ± 1 mg/dL), LDL-C (135 ± 4 vs 144 ± 5 mg/dL) and blood pressure (SBP 124 ± 3 vs 128 ± 3 mmHg; DBP 80 ± 2 vs 82 ± 2 mmHg). CONCLUSION: The riverside and urban populations of Amazonia had similar cardiovascular risks. However, the marked difference in the variables studied suggests that different strategies of prevention should be applied.
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OBJECTIVE: To verify the hypothesis that the pulmonary vein pulsatility index is higher in fetuses of diabetic mothers than it is in normal fetuses of nondiabetic mothers. METHODS: Twenty-four fetuses of mothers with either gestational or previous diabetes (cases), and 25 normal fetuses of mothers without systemic disease (control) were examined. Fetuses were examined through prenatal Doppler and color flow mapping. The pulmonary vein pulsatility index was obtained by placing the pulsed Doppler sample volume over the right superior pulmonary vein and applying the formula (systolic velocity - presystolic velocity)/mean velocity. RESULTS: The mean gestational age of the study fetuses was 30.3±2.7 weeks, and gestational age of the controls was 29±3.3 weeks, with no significant difference in gestational age between groups (p=0.14). Fetuses of diabetic mothers had a mean pulmonary vein pulsatility index of 1.6±1, and those of the control group had an index of 0.86±0.27. CONCLUSION: Fetuses of diabetic mothers had pulmonary vein pulsatility indexes (parameter easily obtained through Doppler echocardiography that may be related to fetal diastolic function) higher than those in fetuses of mothers with normal glycemia.
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Fascicles 1-12, 1753-1906
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Suppl. 1906-12
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Suppl. prelim. 1913-17
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Suppl. 3 1917-33