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*  Kindly find answers herewith for  all your  queries  in details .
1.  Diagnosis is 
duodenal ulcer with 
duodenitis .
2.  
Pentagastrin stimulation test reveals basal and stimulated acid  
    production  by  the  parietal  cells  of  the  stomach ,  pH felling to 1.9
    indicates precise stomach functioning .
3.  Fasting serum gastrin level normal indicates there is no rise of gastrin 
     release  from the circulation .
4.  Antacids reduce excess acid , relieves pain of ulcer , 
simethicone content
     relieves  gas .
5.  H2 antagonists  block the action of 
histamine on the H2 receptors , 
     helping to heal the ulcer .
6.  Dietary  modifications  recommended  
     -  Drink plenty of liquids .
     -  Prefer  soft  , light  diet .
     -  Avoid  oily , spicy , non veg , hot beverages , junk foods etc .
     Behavioral  recommendations  
     -  Avoid  stress , 
anxiety .
     -  Maintain  regular  sound  sleep of  8  hours .
     -  Avoid  
smoking , alcohol if  using .
Hope this  will help you for sure   .
Wishing you fine recovery .
Welcome for any further  guidance .
Regards  .