Vahid Changizi

Department of Radiology, School of Allied, Tehran University of Medical Sciences, Tehran, Iran

[ 1 ] - Origanum vulgare leaf extract protects mice bone marrow cells against ionizing radiation

Objective: Ionizing radiation produces free radicals which induce DNA damage and cell death. Origanum vulgare leaf extract (OVLE) is a natural compound and its capability of scavenging free radicals and its antioxidant activity have been demonstrated by many researchers. In this study, using micronucleus assay, radioprotective effect of OVLE against clastogenic and cytotoxic effect of gamma irr...

[ 2 ] - Evaluation of 226Ra, 232Th, 137Cs and 40K “Agaricus Bisporus” Activity in Cultivated Edible Mushroom formed in Tehran Province- Iran

Introduction Natural and man made radioactive sources exist in our environment they can enter into our food chains. One of these is the soil-mushroom-human chain. High level doses of natural radiation can cause hazards to humans. Materials and Methods Samples of Agaricus bisporus cultivated edible mushroom in Tehran province- Iran were collected from 7 farms. Specific activity of 226Ra, 228Ra, ...

[ 3 ] - Optimization of 3D Planning Dosimetry in a Breast Phantom for the Match Region of Supraclavicular and Tangential Fields

Introduction: The complex geometry of breast and also lung and heart inhomogeneities near the planning target volume (PTV) result in perturbations in dose distribution. This problem can result in overdosage or underdosage in the match region of the three treatment fields. The purpose of this study is to create a homogeneous dose distribution in the match region between the supraclavicular and t...

[ 4 ] - Histological Study of Open Wound Healing with a Light Cure Instrument

Introduction: In the present study, the effects of light cure on wound healing of mice’s skin with complete thickness were studied. Materials and Methods: Forty male mice of NMRI race were placed randomly into two groups of examination and control. Under aseptic and unconscious conditions, a circular wound of 6 mm width with complete thickness of skin was made on the back of each mice. The surg...

[ 5 ] - میزان آگاهی استفاده‌کنندگان در برابر خطرات سولاریوم بررسی آماری در شهر تهران

Solarium or tanning machines are available at gyms, beauty salons and.... Now, it is about 35 years since these devices have been introduced for tanning with ultraviolet radiation (UV). UV radiation having chemical reactions with skin, increases skin pigmentation and helps the formation of vitamin D and calcium absorption. Using solarium in Europe where they get less benefit from direct sunligh...

[ 6 ] - Radioprotective effects of selenium and vitamin-E against 6MV X-rays in human blood lymphocytes by micronucleus assay

Background: Critical macromolecules of cells such as DNA are in exposure to damage of free radicals that induced from the interaction of ionizing radiation with biological systems. Selenium and vitamin-E are natural compounds that have been shown to be a direct free radical scavenger. The aim of this study was to investigate the radioprotective effect of selenium and vitamin-E separately and sy...

[ 7 ] - A study of professional radiation hazards in CT scan and nuclear medicine workers using GTG-banding and solid stain

  Background: CT scan and nuclear medicine exams deliver a great part of medical exposures. This study examined professional radiation hazards in CT scan and nuclear medicine workers.   Methods : In a cross sectional study 30 occupationally exposed workers and 7 controls (all from personnel of a laboratory) were selected. Physical dosimetry was performed for exposed workers. Blood samples were ...

[ 8 ] - Measurement of 226Ra, 228Ra, 137Cs and 40K in edible parts of two types of leafy vegetables cultivated in Tehran province-Iran and resultant annual ingestion radiation dose

Background: The sources of radioactivity in the environment have natural, terrestrial and extraterrestrial, and anthropogenic origins. Plants may get radioactive nuclides in two ways: (i) by the deposition of radioactive fallout, (ii) by absorption from the soil. Materials and Methods: The Concentrations of the natural radionuclides (226Ra, 228Ra, 40K) and the artificial radionuclide (...

[ 9 ] - Application of small angle X-ray scattering (SAXS) for differentiation between normal and cancerous breast tissues

ABSTRACT Background: Coherent scattering leads to diffraction effects and especially constructive interferences. Theseinterferences carry some information about the molecular structure of the tissue. As breast cancer isthe most widespread cancer in women, this project evaluated the application of small angleX-ray scattering (SAXS) for differentiation between normal and cancerous breast tissues....

[ 10 ] - بررسی پرتوگیری ناشی از گاز رادن در کارکنان مراکز رادیوتراپی شهر تهران در سال 1394

Background and Aim: Estimation of radon density  in underground centers is very important. Considering the use of high-energy medical accelerators, radiotherapy departments are usually located in underground floors. The aim of this study was to evaluate staff exposure to radon gas in these centers in Tehran in 2015-2016. Materials and Methods: This is a descriptive,  cross-sectional survey. In...

[ 11 ] - نقش متابولیتها در تشخیص توده های مغزی با استفاده از طیف سنجی تشدید مغناطیس هسته ای و مقایسه غلظت آنها در بیماران تومورال با افراد سالم

Background and Aim: Brain tumors have remained as a significant cause of morbidity and mortality and are often refractory to treatment. The grading of brain tumor has an important implication in clinical management. Currently, magnetic resonance spectroscopy (MRS) is an important dimension in evaluating metabolites and grading brain tumors. The aim of this study is to evaluate metabolites in br...

[ 12 ] - Optimization of Radiation Dose in Cranial Computed Tomography among Adults: Assessment of Radiation Dose against Image Quality

Introduction: The rapid use of computed tomography (CT) scan is of great concern, due to increase in patients’ dose. Optimization of CT protocol is a vital issue in dose reduction. This study aimed to optimize radiation dose in cranial CT and assess modifications in image quality under radiation dose reduction. Material and Methods: A poly(me...

[ 13 ] - Planning, Implementation and Evaluation of Active Learning- Teaching Methods in Inverted Classroom,Peer Learning and Virtual Education among Students in the School of Allied Medical Sciences

Introduction: Education in the field of medical sciences requires using modern learning- teaching methods to enable students to be active in this process and to cultivate creative and thoughtful students. The aim of this study was to design, implement and evaluate active learning- teaching methods in the form of flipped classroom, peer learning and virtual education among paramedical students. ...