Q: Indicate the presence of numerical data in the abstract (whether numerical data plays a key role in medical records), solely using the information from the abstract.
Abstract: We studied the effects of one session of hemofiltration on the mineral metabolism in a group of uremic children. We observed an increase of calcemia, accompanied by positive calcium balance, and a decrease of plasma phosphate and PTH-MM. No substantial loss of plasma 25-OH D was found. It is concluded that hemofiltration has a positive effect on calcemia and is very effective in removing phosphate, but it acts only temporarily on PTH removal. An adequate calcium concentration must be provided in the substitution fluid. 
Question: Does the abstract contain any numerical data?
A:
Yes