objective: active and passive smoking lead to the production of a number of oxidants and antioxidants with various adverse health effects compromising the immune system. tobacco use increases the production of free radicals as well. the purpose of this study was to determine the effects of passive smoking on total antioxidant capacity (tac) of serum and saliva in rats. methods: this experimenta...

introduction: radiation induced bystander effect (ribe) which cause radiation effects in non-irradiated cells, has challenged the principle according to which radiation traversal through the nucleus of a cell is necessary for producing biological responses. what is the mechanism of this phenomenon? to have a better understanding of this rather ambiguous concept substantial number of original an...

the role of oxygen free radicals in the initiation, promotion and progression of carcinogenesis and the protective role of anti-oxidant defenses has been the subject of much speculation in the recent past with conflicting reports in the literature. in recent years, increasing experimental and clinical data have provided compelling evidence for the involvement of oxidative stress in a large numb...