background: the shielding methods in radiotherapy due to delivering an accurate radiation dose to cancer tissues and avoiding unnecessary dose to normal tissues are very important. these methods include lead standard blocks, individual molding and multi leaf collimator (mlc). the mlc method is not still common in iran radiotherapy centers. individual molding is better than the lead block shield...

normal 0 false false false en-us x-none fa introduction: in radiation therapy centers across iran, protection of normal tissues is usually accomplished by either cerrobend or lead block shielding. in this study, the influence of these two shielding methods on central axis dose distribution of photon beam a cobalt unit was investigated in clinical conditions. materials and methods: all measureme...

OBJECTIVE In the present study, a modified limb lead (MLL) system was used to record the Ta wave in sinus rhythm and with AV block in male patients. METHODS Eighty male subjects (mean age 36 ± 7 years) in sinus rhythm and 20 male patients with AV block (mean age 72 ± 5 years) were included in this study. Standard limb lead (SLL) ECGs and MLL ECGs were recorded for 60 seconds each with an EDAN...

Knowledge on the lithologically inherited variation in present day Pb isotope ratios in soils is remarkably limited. Such information is essential to determine the anthropogenic Pb fraction and anthropogenic Pb sources in Pb polluted soils. This study presents results of a survey of subsoil samples of approximately 350 rural locations covering the entire Netherlands, for which the bulk geochemi...

Abstract Funding Acknowledgements Type of funding sources: None. Background First-degree atrioventricular (AV) block (PR interval >200 ms) is considered a benign condition with rare progression to higher degree AV block. The site determined electrophysiological (EP) study and measurement His-ventricular (HV) interval, normal values below 55 ms. Prolonged HV > 70 ms predictive high...

Concentrations and isotopic compositions of lead in the total and mobile (acid-soluble and carbonatebound) forms were determined in remote and roadside Chestnut soils in the dry steppe region of Low Volga, Russia. As a reference to evaluate the level of modern soil contamination with lead, we used ancient soil buried under a Bronze Age kurgan about 4500 years ago. In comparison with buried soil...

A 57-year-old womanwith a history of dizziness due to episodes of complete heart block and bradycardia was referred to the electrophysiology ward for pacemaker implantation. A dual chamber pacemaker (Medtronic, Relia, Medtronic, Minneapolis, USA) was implanted. Its analysis showed normal function (atrial lead capture threshold 0.5 V at 0.4 ms, ventricular lead capture threshold 0.75 V at 0.4 ms...