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Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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Nuno Fonseca Filomena Caetano José Santos Filipe Seixo Leonel Bernardino Isabel Silvestre Paula Cardoso Filomena Segurado Lopes Inês 《Revista portuguesa de cardiologia》2004,23(3):365-375
INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function. 相似文献
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As in the principal industrial countries, Brazilian women have lived longer than men. However, paradoxically, women present higher morbidity indicators than men. Knowledge of the Brazilian pattern regarding this matter could be a useful contribution to an understanding of their determinants in our specific reality, as well as enabling us to foresee future trends that would make it possible to plan adjustment in the health system. A morbidity study based on data from the National Household Sample Survey (PNAD/IBGE), was undertaken in ten Brazilian states in 1986 with this in view. Coefficients of the prevalence of perceived morbidity, demand for and utilization of health services according to sex, standardized by age and using the direct method, were built up. As a measurement of the differentials, sex ratios were calculated. The excess of perceived morbidity in women was constant in all the regions. The sex differential in the utilization of health services showed regional variations, suggesting a relationship with the health services supply. Sex differentials were not observed in childhood; the highest values were found during the woman's reproductive period, decreasing sharply after 60 years of age. The pattern is very similar in all regions. In the present study, the findings could be partially explained by the methodology adopted, but they are similar to the findings reported in other countries. The intense transformations in the reproductive pattern and in the social status of Brazilian women probably have a considerable impact on the health status and on the recourse to health services, not as yet evaluated.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Ulisses Xavier da Silva Neto Ivaldo Gomes de Moraes Vania Portela Ditzel Westphalen Renato Menezes Everdan Carneiro Luiz Fernando Fariniuk 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e53-e57
OBJECTIVE: The aim of this study was to measure leakage of 4 resin-based sealers. STUDY DESIGN: Four groups of premolars (n = 60) were prepared using GT Rotary files and the crown-down technique and filled by the single-cone technique with AH26, AHPlus, EndoREZ, and an experimental MBP as sealer. Leakage was measured using the fluid filtration method after 15, 30, and 60 days and determined as microL/min(-1) x 10 psi. RESULTS: Statistical analysis by ANOVA and Tukey HSD test indicated that root fillings with AH Plus and the MBP showed lower leakage values after 15 days (P < .05). At 30 days, AH26 presented higher leakage values when compared to other sealers (P < .05). At 60 days, MBP and AH Plus presented the lower leakage values, differing significantly from EndoREZ (P < .05). CONCLUSION: It was observed that AH Plus and the experimental MBP showed lower leakage after 60 days than AH 26 and EndoREZ. 相似文献
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Maria De Ftima V. Marques Cristiane A. Henriques Jos Luiz F. Monteiro Sonia M. C. Menezes Fernanda M. B. Coutinho 《Macromolecular chemistry and physics.》1997,198(11):3709-3717
Y zeolites with different sodium contents and a sodium mordenite were evaluated as support for bis(cyclopentadienyl)zirconium dichloride as catalyst for ethylene polymerization. The results showed that, although the activities of the supported catalysts were lower than that of the homogeneous system, the average molecular weight of the polyethylene produced from the former was in general much higher than that of the polymer produced in solution. Contrary to the expected trend if the specific area was the dominant factor for catalyst activity, the best catalyst was the one supported on NaM zeolite. Thus, our results indicate that the concentration of framework aluminium atoms is the dominant factor, but that the contribution of the external surface is also important. 相似文献
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BACKGROUND--Chronic bronchitis causes high morbidity and mortality throughout the world. It is basically a preventable disease. However, few population based studies of chronic bronchitis have been carried out in less developed countries. METHODS--A population based cross sectional survey was conducted to determine the prevalence of chronic bronchitis and associated risk factors in an urban area (Pelotas) of southern Brazil. 1053 subjects aged 40 years and over (90.3% of eligible subjects) were interviewed using the ATS-DLD-78 questionnaire. RESULTS--Of the subjects interviewed 12.7% were classified as having chronic bronchitis. In univariate analyses a significant increase in the relative odds of chronic bronchitis was seen in men (OR = 2.17, 95% CI 1.50 to 3.13), low family income (OR = 2.60, 95% CI 1.47 to 4.47 for lowest quartile), low schooling (OR = 4.65, 95% CI 2.36 to 9.18 for those with no schooling), smoking habits (OR = 6.92, 95% CI 4.22 to 11.36 for smokers of 20 or more cigarettes per day), high occupational exposure to dust (OR = 2.48, 95% CI 1.56 to 3.94), inadequate housing (OR = 2.09, 95% CI 1.22 to 3.58), high level of indoor air pollution (OR = 1.86, 95% CI 1.16 to 2.99), and reported childhood respiratory illnesses (OR = 2.08, 95% CI 1.25 to 3.49). Multiple logistic regression resulted in the identification of the following independent risk factors: family income (OR = 1.99, 95% CI 1.04 to 3.81 for subjects in the lowest quartile compared with those in the highest quartile), schooling (OR = 5.60, 95% CI 2.52 to 12.45 for subjects with no schooling compared with those with nine or more years), smoking (OR = 8.10, 95% CI 4.46 to 14.71 for smokers of 20 or more cigarettes per day compared with non-smokers), and history of major respiratory illnesses in childhood (OR = 2.16, 95% CI 1.20 to 3.85). CONCLUSIONS--Low family income, poor schooling, smoking, and childhood respiratory illnesses were significantly associated with chronic bronchitis. 相似文献