الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
SUMMARY
The present work (thesis) provides reasonable understanding to the effect of radiation on blood viscosity, dielectric properties (conductivity, permittivity, dielectric loss and cole-cole parameters), blood film and osmotic fragility rat’s blood. It contains five chapters and (97) references
The first chapter:
This chapter introduces a general introduction to the interactions of ionized radiation with biomaterial which induced cell effects. The chapter is divided into eight sections. This chapter represent an introduction to photons (x or γ-rays) which interact with matter that leads to three processes of interaction concerning with energy of photons. The second section gives in briefly, definition to interaction as a result of energy transfer that induces the chemical processes which lead to biological changes. The third section introduces the biological effects of radiation explaining two mechanisms (direct and indirect effects) in which radiation ultimately affect the cells and hypotheses of radiation dose relationship also this chapter gives introduction of linear accelerator composition
This chapter gives a Review of Literature of effects of radiations on blood via biophysical measurements. The Aim of the work section gives in a brief, the outline proposal of present work as the following:
Study the biological effects of X-ray 6 MV emitted from linear accelerator on the red blood cell membrane, and to derive useful parameters for the evaluation of radiation effects on the osmotic fragility of the membrane; whole blood viscosity and the blood film test were also measured and the effect of radiation on dielectric properties on the red blood cell membrane was discussed.
The second chapter:
The chapter is divided into nine sections is devoted to theoretical background of red blood cell membrane structure and its role functions in elasticity, permeability, osmotic fragility, viscosity, conductivity and permittivity and its importance in cell-cell communication and cell adhesion. Also in this chapter gives the basic principle of blood tests such as viscosity, osmotic fragility, blood film and electrical properties, definitions and explanations of impedance, conductivity and permittivity.
The third chapter:
This chapter provides measurement techniques used as the basis of this work. The chapter is divided into six sections. The first section gives materials and methods used for animal preparations. The second section explains irradiation facility the third section explains method used for blood viscosity measurements then the osmotic fragility measurements. The fifth section explains in vitro dielectric measurements and by using cell capacitor technique. Finally the statistical analyses of the data were used according to Harnet [93] by calculating arithmetic means and standard error for red blood cells osmotic fragility, viscosity and dielectric measurements.
The fourth chapter:
In this chapter, the experimental data used for 5 groups first is the control group and other groups 4 groups are equally divided to be exposed to X-ray linear accelerator machine for doses 700,800,1000 and 1200 cGy for two delayed points 3days post irradiated and 9 days post irradiated. The chapter is divided into four sections. The first section gives information of osmotic fragility of red blood cells which indicates clarifies difference of irradiated animals from the control groups. The second section gives the results and discussed data obtained from blood viscosity test which increase in 3days post irradiated subgroups then increase as compared with the control group and the all data are obey the power model low The third section gives the results and discussed data obtained from 3days post irradiated which whole body exposed to 6MV X-rays In this experiment, the plots of impedance data and dielectric properties (conductivity and permittivity) are presented and discussed. Also the fitting parameters (R0, R∞ and τ) of the Cole-Cole equation of impedance spectra for rat’s blood are presented in tables for both non-irradiated and irradiated rats. The fourth section gives the results and discussed the data obtained from blood film test for irradiated and non irradiated groups which depicts a clarify difference for each one of the eight subgroups compared with the control group in size, morphology and shape.
The fifth chapter:
This chapter, provides in briefly the conclusions with final remarks as following
Ionizing radiation includes alterations in membrane proteins, peroxidation of unsaturated lipids accompanied by perturbations of the lipid bilayer polarity. The radiation includes oxidative damage in phospholipids initiated mainly by free radical products and leading to the appearance of various degradation substances and modified molecules. When hydro peroxide residues are produced in the bilayer core, hydrophobic interactions between adjacent phospholipids become unstable, allowing easier penetration of water molecules. Significant degradation of membrane function and structure may favor apoptosis.
The obtained results showed that whole blood measurements are affected by 6MVX-ray and as the radiation increase the damage of cell membrane increase which lead to change in their physical and chemical properties e.g. (osmotic fragility, viscosity, shape, size, ion concentrations in and out the cell) which lead to change their in vital roles and their mechanism of action as a result of some types of blood disease, one of the more common blood disorders, occurs when level of healthy red blood cells (RBCs) in body becomes too low. This can lead to health problems as a result of few days after exposure the rat’s probability of getting diseases increased.
Physical properties of the blood directly affect blood flow, and sufficient blood flow is essential for the health of all organs.
As the dose increase the probability of cell damage of erythrocyte cell membrane increase which lead to change their vital roles and their mechanism of action as a result of some types of blood disease.
More over it is necessary to consider blood rheology measurement to be included in routine medical investigation.
Counting of blood cells in routine medical invigorations is not enough to evaluate the radiation hazard and it is necessary to consider the blood cells biophysical properties rather than its numbers.