anchor.diff:  1580,"Methylphenidate Tablet [CD]"
   1581,"Methylprednisolone (as Sodium Succinate) Infusion"
   1582,"Methylprednisolone (as Sodium Succinate) Injection"
  -1583,"Methylprednisolone Acetate Injection [IS]"
  -1584,"Methylprednisolone Tablet [IS]"
  +1583,"Methylprednisolone Acetate Injection"
  +1584,"Methylprednisolone Tablet"
   1585,"Methylthioninium Injection"
   1586,"Methysergide Tablet"
   1587,"Metoclopramide  (Multiroute)"
  
positive.code: 2271,"Simple Linctus"
  2272,"Simvastatin Tablet"
  2273,"Sirolimus Oral Solution"
  2274,"Sirolimus Tablet [IS]"
  2275,"Sitagliptin Tablet"
  2276,"Sodium Aurothiomalate Injection"
  2277,"Sodium Benzoate Injection"
  
negative.code: 2101,"Proflavine Cream"
  2102,"Progesterone Injection"
  2103,"Progesterone Pessary"
  2104,"Tacrolimus Capsule (Prograf)"
  2105,"Proguanil 100mg/Atovaquone 250mg Tablet"
  2106,"Proguanil Hydrochloride Tablet"
  2107,"Promazine  Tablet"
  