context is important here; generally the right term is "internship", but you can easily use decriptive "clinical studies of medical graduates"; however it can be considered as a position, appointment of professor.

It's not simply an internship as we know it, it is a mandatory kind of training in the core of the SIXTH YEAR medical students' curriculum in Russia. In other words, during this internship students specialize in their field of choice, that is the one they are going to practice in.

For more details on what is included in this kind of "pre-diploma" practical training, see the following sites (see the usages of this word):