For the patients who are diagnosed with SJS, how many of them have a normal level of total protein?
diagnosed with SJS refers to Diagnosis = 'SJS'; normal level of total protein refers to TP > 6.0 and TP < 8.5;
SELECT COUNT(T1.ID) FROM Patient AS T1 INNER JOIN Laboratory AS T2 ON T1.ID = T2.ID WHERE T1.Diagnosis = 'SJS' AND T2.TP > 6.0 AND T2.TP < 8.5