الفهرس 
The cellOnly 14 pages are availabe for public view
 |  | from | 143 |  |  |
| | | from | 143 | | |
Abstract
the degree of genetic abnormalities produced by X-ray aRer chronic low dose exposure which is considered one of the genotoxicmts. The biological consequences of exposure to ionizing radiation include gene mrrtation, chromosome aberrations, malignant transformation and cell death. These effects are attributed to the production of irreversible damage at the time of the irradiation. However the common cytogenetic observed end point are chromosomal aberration, so it the topic of our study. The study was undertaken on 46 individuals, divided into two groups ,exposed and control groups , the exposed one includes 39 X-ray exposed workers employed in radio diagnosis departments ,and the control group includes ’/ persons not exposed to radiation or any other factor that may affect the chromosomes ,both groups were of almost similar ages and sex. Both groups were inte~ewedfo r proper medical history and blood samples were collected from them for hematological and cytogenetic study. Complete blood picture was used to detect hematological changes, however the cytogenetic studies have incl~ided solid staining. Solid staining technique was done by addition of nutritional media, antibiotic, phytohaemagglutinin (mitotic inducer) to heparinized blood sample for 72 hour at 37T Two’ hours before harvesting colcirnide was added to culture media (to arrest cells cycle at metaphase).This was followed by treatment of the culture with hypotonic potassium chloride solution and their fixation in fixative solution . They were spread on glass slides and stained with Gigm,?%g glglj~~ &&g WE m~~h& Ddp% Summery and Conclusion and covered. Followed by examination at 1 000 Microscopic Magnification and photographs were taken. The results obtained showed : haematotoxic effect, appeared in the form of anemia which was the only significant component in blood picture in 9 persons. Genetic effect of X-ray showed non significant increase in total chromosomal aberrations (including and excluding gap). These specific stn~ctural aberrations were non significantly increased also, as regards gaps, breaks, dicentric chromosomes and tetraploidy. However acenteric fragment was the only significant aberration in the exposed persons. Meantime, an increase in the mitotic activity of peripheral blood lymphocyte of X-ray exposed workers was observed. All the results had no relationship to age or sex. Therefore, the fact that the value of peripheral blood cuIture for occqational dosimetry depends mainly on its ability to detect a significant diflerence in the frequency of chromosomal aberrations between radiation exposed persons and individuals not exposed or from the general population. Such differences was not demonstrated in the present work. So this study c.onfirms the opinion held by other workers that the low level of aberration detected , necessitates an increase in the size of the sample examined .This seems to be an essential requirement in studies of radiation induced chromosome aberrations in personnel exposed to low doses of radiation at low dose rates