作者: Bruce M. Fenton
DOI: 10.1016/S0167-8140(97)00084-4
关键词:
摘要: Abstract Background and purpose : Numerous studies have demonstrated improvements in the oxygenation of tumor cells following both irradiation carbogen breathing. The current were initiated to measure combined effects inhalation plus single multi-dose on oxygen availability, better define underlying physiological relationships. Materials methods Using KHT murine sarcomas, radiation was delivered tumor-bearing legs non-anesthetized mice. Tumors quick-frozen prior or multifraction breathing, intravascular HbO 2 saturation profiles determined cryospectrophotometrically. Results levels for blood vessels located near surface initially decreased 10 Gy irradiation, then increased remained elevated. Interior unchanged. Following 2.5 Gy, changes minimal. At 24 h significantly compared non-irradiated controls, breathing produced no additional benefit. five fractions throughout volume higher animals than air controls. Conclusions Although peripheral substantial availability nearer center at very low levels. utility enhancing maintained clinically relevant fractions. doses, radiation-induced enhancements overshadowed effect. For either a decrease percentage with content did not appear be major factor reoxygenation tumor.