Very few of my own references include full names, so I guess if I were faced with this, I would use an output style that doesn’t abbreviate the names, and the exact way they are listed, would be output. However, how is the name listed in Pubmed? A quick search showed it indexed as JT not J Th. so what makes you believe it should be Th. ?
Int J Appl Radiat Isot. 1977 Mar;28(3):271-5.
Sumpeak calibration of 123I.
Brinkman GA, Lindner L, Veenboer JT.
PMID: 863531