Dear Abhay,
The eligibility criteria for B.Sc. in Nuclear Medicine is that you should pass your 10+2 or equivalent from any recognised university with subjects like Physics, Chemistry, Biology or Mathematics. And also minimum 50% marks. Rank card is prepared based on your career marks. The students with PCM in 12th were given separate ranks. Dr. MGR medical university chennai is a good institute to pursue B.SC. Nuclear Medicine. The average annual fee here is INR 27,000 which is quite affordable. Once you graduated you can  become Radiologist, Research Assistant, Professor or Nuclear Medicine Technologist.

Hello aspirint,
I am here for helping you....
you definitely can take admission in MGR University for nuclear medicine either it may be BSc or MSc so for that you have to fulfill some eligibility criteria for this university which you can check on going through the link which I am providing you below:
https://www.careers360.com/university/tamil-nadu-dr-mgr-medical-university-chennai
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I hope it will be beneficial for you....
For more queries you can upvote my answer and can ask in the comment section below...
Best of luck...