الفهرس 
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Abstract
Cancer treatment is one of main challenges that face the scientific centers all over the world. The cancer incidence percentage increases year after year.
It is known that Hyperthermia -elevated tissue temperature by radio frequency (RF) and microwave fields- has beneficial effects in cancer therapy. Particularly, in noninvasive electromagnetic (EM) hyperthermia, one attempts to focus the energy in the tumor region, while avoiding damage to the surrounding healthy tissue. In order to understand these phenomena and facilitate their use for therapeutic purposes, there are several numerical techniques are employed for modeling the processes involved in interactions between EM fields and biological systems.
The possible sources of error of the biologic sciences are coupled with the sources of error associated with RF engineering and dosimetry. It is often difficult to make meaningful comparisons between studies.
Presented in this thesis are the following theoretical investigations carried out on non-invasive RF/ microwave hypothesis of superficial of malignant tumors in human body.
Fundamentals concepts of electromagnetic wave propagation through biomass and it’s interaction with it, are discussed.
The present work is concentrated on the use of horn antenna as a noninvasive hyperthermia applicator so that the design of antenna that is appropriate for the used microwave generator has been done.
In the present work, microwave with two power levels (40W and 50W) and RF with (20W) have been exposed to Ehrlich tumor.
Tumor bearing animals were divided into two main groups first group were injected intramuscularly and second group were injected subcutaneously .from the main groups there are subgroups divided to eight groups two of them are control groups(untreated) the other groups are divided to groups exposed to microwave for 8 min and the other groups exposed to RF at power for 35 min.
Tumor growth was examined regularly every 2 days, in addition to measure some dielectric properties of the solid tumor after killing the animals.
Treatment of Ehrlich ascities tumor with RF has no effect on superficial tumor volume, while microwave energy has some cytotoxic effects on tumor cells.
II. Conclusion
• The microwave frequency at 2450 MHz is recommended as the frequency of operation (ISM frequency) for superficial hyperthermia treatment.
• Decreasing in the tumor volume was observed either on using 40W and 50W but with the higher power it was more decreased.
• The relative permittivity of tumor decreased with increasing the applied frequency in RCL instrument.
• The conductivity increased exponentially with increasing frequency in RCL instrument for all cases.
• The imaginary permittivity for tumor decreased with increasing the applied frequency in RCL instrument.
• The effect of microwave therapy increases with increasing of its energy.
• Conductivity describes the ability of a substance to dissipate energy, while permittivity describes the ability of a substance to store energy.
• Control malignant tumor tissue has been shown to exhibit a larger permittivity and conductivity than treated tumor tissues. This might be associated with the fact that tumor cells have a higher water content and sodium concentration than normal cells, as well as different electrochemical properties of their cell membranes.
• There is no significant difference in the dielectric properties exist between sample exposed to RF and control samples for subcutaneous and intramuscular tumors.
Future Work:
Future research directions should examine:
1. Mechanisms of how cells react to changes in their thermal environment and clarification of thresholds for thermal damage in humans.
2. Accurate EM and thermal dosimetry including further investigations in the following fields: (a) modeling power deposition and estimation of EM energy absorbed by tissues exposed to EM radiation, (b) electrical-thermal modeling for thermal therapy with various models of heat transfer in living tissues, and (c) models of EM energy deposition in humans combined with appropriate models of the human thermoregulatory responses to predict the potential hazards associated with specific EM exposure conditions.
3. Human and animal studies on (a) CNS changes in heat-related illnesses using quantitative immunopathological techniques at the cellular and ultrastructural levels, (b) effect of EM exposure on cognitive performance, (c) effect of prolonged or chronic exposure at ambient temperatures (<41°C), and (d) carcinogenic risk of heat, especially for low-temperature hyperthermia.