Hello,Mr.mani
You cannot transfer between these two places directly. You can go as follows:
1)from chengdu airport to chengdu railway satation. Take bus no.300.
2)from chengdu railway station to chongqing railway station. Take train
3)from chongqing railway station to chongqing medical school. Take light rail line 2 or bus no.462, 109, or 463