17 research outputs found

    Organic and inorganic compounds in limestone weathering crusts from cathedrals in Southern and Western Europe

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    Limestone and weathering crusts have been studied at the major cathedrals of Sevilla, in southwestern Spain, and Mechelen, in northern Belgium. These cities have very different climatic and environmental conditions. The deterioration characteristics of the limestone in both localities have been compared. Detailed petrographical characterization was carried out for the different building stones, including restoration materials. The bulk and trace inorganic composition of the stones and crusts was assessed, and the leachable ions were analyzed, while elemental concentration profiles with depth were studied with electron microprobe analysis. The organic compounds in the black weathering crusts have also been studied and compared. In the different types of limestone, the deterioration is largely influenced by the petrographie characteristics of the stone. Gypsum crusts from Mechelen and Sevilla show variable textures, even on the same stone types. Sulfatation of calcite provides Ca for the gypsum crusts. Except fora part of the Sr and Fe fractions in the crust, all other elements may be of external origin. Concentrations of the various elements are more or less comparable in crusts from Mechelen and Sevilla. External inorganic particles consist of fly ash, quartz, clay, and glauconite. Most of the organic material appeared to be of anthropogenic origin, due to combustion processes, while a minor fraction originated from cuticular waxes of higher plants.This work was supported by the Commission of the European Community, Project STEP-CT90-0107.Peer Reviewe

    Osteomas fronto-etmoidais: aspectos clínicos e cirúrgicos Fronto-ethmoid osteomas: clinical and surgical aspects

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    Introdução: Osteomas fronto-etmoidais são os tumores benignos mais freqüentes dos seios paranasais, podendo evoluir com complicações infecciosas e destruição das estruturas adjacentes. Apesar de serem relativamente freqüentes, poucos são os casos que necessitam de tratamento cirúrgico. Objetivo: Relatar um grupo de nove pacientes com osteoma frontal ou etmoidal, e discutir a apresentação clínica e o tratamento mais adequado desta doença. Forma de estudo: Clínico prospectivo. Material e Método: Realizado estudo clínico prospectivo de nove pacientes, operados no HSPE-FMO e no Hospital São Luiz de São Paulo, no período de 1995 a 1999. O tratamento cirúrgico foi a opção terapêutica escolhida neste grupo. Foi avaliada a evolução clínica no pós-operatório. Resultados: Dos nove pacientes, cinco eram do sexo feminino e quatro do sexo masculino, com idade variando de 12 a 55 anos e com média etária de 39,55 anos. Todos os pacientes tiveram resolução do quadro inicial, sendo que apenas um evoluiu com seqüelas (hiposmia). Conclusão: Baseados na revisão bibliográfica e nos casos acompanhados, concluímos que as lesões localizadas próximas ao óstio de drenagem do seio frontal, as que ultrapassam os limites dos seios frontal e etmoidal, bem como aquelas localizadas no etmóide, devem ser tratadas cirurgicamente.<br>Introduction: Fronto-ethmoidal osteomas are the most frequent paranasal sinus benign tumor and they may envolve with either infectious complications and destruction of adjacent structures. Though they are relatively frequent, few of them are cases requiring surgery. Aim: To report on a group of nine patients with frontal or ethmoidal osteoma, as well as to discuss the clinical presentation and the most suitable treatment of this disease. Study design: Clinical prospective. Material and Method: A prospective clinical study of nine patients who were submitted to surgery at the HSPE-FMO (State Public Servants Hospital) of São Paulo, and at the São Luiz Hospital of the city of São Paulo, in the period from 1995 to 1999. The surgical treatment was the therapeutic option selected in this group. The clinical evolution was assessed during the postoperative period. Results: Of the nine patients, five were females and four a male, ages ranging from 12 to 55 years, with an average age of 39,55 years. All the patients had a resolution of the symptoms and only one of them presented sequels (hyposmia). Conclusion: Based on both the literature review and on the cases followed, the authors concluded that the lesions compromising the drainage of the frontal sinus osteos, those with destruction of the sinus limits as well as any ethmoidal tumors should be surgically treated
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