الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Cryosurgery is a branch of therapeutics that makes use of local freezing for the controlled destruction and/or excision of 1i vi ng t i ssue. Attempts to utilize cold for the destruction of tissue date back to the middle of 19th century,, when an Englishman, James Arnott, applied ice-cold brin to malignant lesions. Throughout the years, the effect of cold on man and animals has been analysed from both the clinical and biological point of view. Until Dr. Irving Cooper in (1961) who devised a closed cryogenic: system using the liquid nitrogen to produce a temperature of as low as -196 C which was able to cause the local destruction of tissue at a depth of several centimeters. As regards the cryobiological basis of cryosurgery, •freezing represents removal of pure water from solution and its isolation into biologically inert foreign bodies,, the ice crystals. The destruction of cells by freezing is based mainly on the •formation of intracel lular ice crystals and protein denaturation. Crystallization leads to cellular dehydration? the rupturing of cell membranes and to a rise of electrolyte concentrations to toxic: levels- The small vessels are thrombosed and the local