Effect of the substitutional elements on the microstructure of the Ti-15Mo-Zr and Ti-15Zr-Mo systems alloys

AbstractTitanium alloys have excellent biocompatibility, and combined with their low elastic modulus, become more efficient when applied in orthopedic prostheses. Samples of Ti-15Mo-Zr and Ti-15Zr-Mo system alloys were prepared using an arc-melting furnace with argon atmosphere. The chemical quantitative analysis was performed using an optical emission spectrometer with inductively coupled plasma and thermal conductivity difference. The X-ray diffractograms, allied with optical microscopy, revealed the structure and microstructure of the samples. The mechanical analysis was evaluated by Vickers microhardness measurements. The structure and microstructure of alloys were sensitive to molybdenum and zirconium concentration, presenting α′, α″ and β phases. Molybdenum proved to have greater β-stabilizer action than zirconium. Microhardness was changed with addition of molybdenum and zirconium, having Ti-15Zr-10Mo (436±2HV) and Ti-15Mo-10Zr (378±4HV) the highest values in each system

Correção cirúrgica dos aneurismas da aorta: novo dispositivo que transforma qualquer tipo de prótese em prótese intraluminal Surgical correction of aortic aneurysms: a new device for conversion of any graft of intraluminal one

Os autores propõem o tratamento dos aneurismas da aorta com prótese intraluminal. É usado um novo dispositivo que transforma prótese de tipo, tamanho e diâmetro diferentes em prótese intraluminal, excluindo qualquer tipo de sutura para a fixação, e usando apenas uma ligadura circunferencial extravascular. Entre maio de 1989 e janeiro de 1993, 22 pacientes foram submetidos a aneurismectomia da aorta usando esta técnica: 12 pacientes com dissecção aguda da aorta tipo I e II de DeBAKEY, 1 paciente com dissecção aguda da aorta tipo III de DeBAKEY, 2 pacientes com aneurisma da aorta descendente, 2 pacientes com aneurisma da aorta toracoabdominal e 5 pacientes com aneurisma da aorta abdominal. Três pacientes evoluíram para o óbito no pós-operatório por acidente vascular cerebral, trombose mesentérica e infecção pulmonar, respectivamente. Os pacientes sobreviventes estão sendo seguidos trimestralmente em ambulatório e encontram-se assintomáticos. O uso do anel rígido sulcado de Delrin (R) simplifica a técnica cirúrgica, reduzindo o tempo de circulação extracorpórea e de parada cardíaca, dispensando o uso de hipotermia profunda e reduzindo o sangramento. Permite ainda o seu uso em qualquer local da aorta de maneira rápida, fácil e a baixo custo.The authors propose the treatment of aortic aneurysms by using an intraluminal graft. A new device which transforms any kind of graft of different sizes and diameters into an intraluminal one is described. This new device just needs an extra-vascular circunferential ligature and does not require any fixation suture. The use of the rigid, sulcated DELRIN (R) ring simplifies the technique shortening the duration of the surgery, reducing surgical bleeding and dispensing the use of profound hypothermia and platelet transfusion. Between May 1989 and January 1993, 22 patients were submited to aneurysmectomy of the aorta using this technique. Twelve patients exhibited acute aortic dissection (type I and II DeBakey), one DeBakey type III acute aortic dissection, two presented descending aortic aneurysm, two cases were of thoraco-abdominal aortic aneurysm and five aneurysms of abdominal aorta. Three patients died in the imediate post-operative period from cerebrovascular accident, mesenteric thrombosis and pulmonary infection. The survivors have been followed up as outpatients

Update on the Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Guideline of the Brazilian Society of Cardiology-2019

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