There is a definite place at which the brain begins and the spinal cord ends

The answer is the spinal cord starts at the occipital bone where it passes over the foramen magnum, and encounters and go in the spinal canal at the start of the cervical vertebrae. The spinal cord encompasses down to amid the first and second lumbar vertebrae where the spinal cord ends.

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.