You can't get a job directly in space center. Every kind of professionals are required at the space center such and medical personnel are also one of them but to be at a space centre you have to be a astronaut first and for that you must have to qualify for all the required attributes. Height, physical and medical fitness and various criterion you have to fulfill and then you must have to join any space organization such as ISRO, NASA, etc. Then you interest and performance there would decide your selection as a staff at space centre.

Hope it helps.

All the best !