the hot compression tests were carried on x45crniw189 valve steel (x45) in the temperature rangeof 1000– 1200 °c and the strain rate range of 0.004 – 0.5 s-1 in order to study the high temperaturesoftening behavior of this steel. for the exact prediction of flow stress, the effective stress-effectivestrain curves were obtained from experiments under various conditions. on the basis of experimen...

granulocytic sarcomas (chloromas) are rare extramedullary tumors consisting of primitive granulocytic cells. we report here on a case of a 23-year-old man who presented with a generalized swelling. he is known case of acute myelomonocytic leukemia. granulocytic sarcomas are rare, destructive, extramedullary tumor masses that consist of immature granulocytic cells. in this unusual patient's case...

multiple aorto-cardiac cavity communications is very rare but important complication of prosthetic aortic valve endocarditis. the case below illustrates multiple aorto-cardiac cavity fistula formation following prostethic aortic valve endocarditis presented with slowly progressive symptoms of heart failure. a brief review of surgical reconstruction and the existing literature are presented, inc...

background: the adult cardiac surgery databank (acsd) of tehran heart center was established in 2002 with a view to providing clinical prediction rules for outcomes of cardiac procedures, developing risk score systems, and devising clinical guidelines. this is a general analysis of the collected data. methods: all the patients referred to tehran heart center for any kind of heart surgery betwee...

giant left atria are defined as those measuring larger than 8 cm and are typically found in patients who have rheumatic mitral valve disease with severe regurgitation. enlargement of the left atrium may create compression of the surrounding structures such as the esophagus, pulmonary veins, respiratory tract, lung, inferior vena cava, recurrent laryngeal nerve, and thoracic vertebrae and lead t...

background: about half of all patients who undergo mitral valve surgery suffer from atrial fibrillation (af). cox described the surgical cut-and-sew maze procedure, which is an effective surgical method but has some complications. this study was designed to evaluate the efficacy of a substitution method of radiofrequency ablation (rfa) for patients undergoing mitral valve surgery with af. metho...

To investigate the prevalence of Mycobacterium paratuberculosis (M. avium subsp. paratuberculosis)infection among cattle slaughtered in Ahvaz abattoir, samples were taken from 250 cattle. Before slaughter,sex and age were assessed. Thereafter, samples were taken from ileocecal valve, rectum mucosa, ileocecallymph node and stool. All smears which taken from these samples were stained by Ziehl-Ne...

Introduction: Heart valve disease in pediatricsis an increasing global concern, especially in developing countries. This study aims to determine the clinical outcomes of pulmonary valve replacement (PVR) surgery in pediatrics. Methods: The authors retrospectively identified all pediatrics undergoing PVR surgery at Imam Reza hospital (Mashhad, Iran) between 2000 and 2020. Their medical records...

transcatheteraortic valve implantation, first introduced in 2002, has been established as an alternative modality for patients deemed not suitable for open-heart surgery. the anatomical vicinity of the atrioventricular node and the his bundle to the non-coronary and rightcoronary aortic cusps predisposes patients to conduction abnormalities in case of severe calcification or mechanical trauma d...