موضوع: A case study on GIT physiology الإثنين أكتوبر 03, 2011 6:50 am
Harold, a fifty-eight year old grocery store manager, had recently been waking up in the middle of the night with abdominal pain. This was happening several nights a week. He was also experiencing occasional discomfort in the middle of the afternoon. Harold decided to schedule an appointment with his physician. The doctor listened as Harold described his symptoms and then asked Harold some questions. He noted that Harold's appetite had suffered as a result of the pain he was experiencing and as a result of the fear that what he was eating may be responsible for the pain. Otherwise, Harold seemed fine. The doctor referred Harold to a physician that specialized in internal medicine and had Harold make an appointment for a procedure called an endoscopy. The endoscopy was performed at a hospital later that week. During the procedure, a long, thin tube was inserted into Harold's mouth and directed into his digestive tract. The end of the tube was equipped with a light source and a small camera which allowed the doctor to observe the interior of Harold's stomach. The endoscope was also equipped with a small claw-like structure that the doctor could use in order to obtain a small tissue sample from the lining of Harold's stomach, if required. The endoscopy revealed that Harold had a peptic ulcer. Analysis of a tissue sample taken from the site showed that Harold also had an infection that was caused by Helicobacter pylori bacteria. The doctor who performed the endoscopy gave Harold prescriptions for two different antibiotics and a medication that would decrease the secretion of stomach acid. The doctor also instructed Harold to schedule an appointment for another endoscopy procedure in 6 months.
1-Describe the functions of the following components of gastric juice:
a. Hydrochloric acid.
c. Intrinsic factor.
2- Why don’t the components of gastric juice damage the wall of the stomach in the absence of a H. pylori infection?
3- Why don’t most other types of bacteria produce ulcers?