Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a gemcitabine stimulus. Gemcitabine is a 2'-deoxycytidine having geminal fluoro substituents in the 2'-position, and is used as a drug in the treatment of various carcinomas.
response to 2\'-deoxy-2\',2\'-difluorocytidine