Date :- 15th May
Topic :- GIT

(34) The answer is B. Vascular endothelium is rich in prostacyclin synthetase which produces prostacyclin from the cyclic endoperoxidases. Thromboxane A2 is produced by theaction of platelet thromboxane synthetase on cyclic endoperoxides (C). It stimulates plateletadhesion and aggregation (E) by inhibiting platelet adenyl cyclase (A). It is a prostaglandinwith a very short half life (D).

The answer is B, E, A. The common pathway (produced by extrinsic or intrinsic routes) results in the conversion of prothrombin to thrombin, which converts fibrinogen tofibrin monomer.

The extrinsic pathway is the result of the action of thrombokinase produced by tissueinjury.

The intrinsic pathway results in clotting without the participation of tissue injury factors.

The production of plasmin (D) is the result of the action of activators on plasminogen and is responsible for the solubilization of fibrin. Fibrin is not produced by fibroblasts (C).

37
The answer is E. Mallory bodies are usually found in alcoholic hepatitis, but occur in other conditions, i.e., Indian childhood cirrhosis.

The others are the histological hallmarks of acute hepatitis; acidophilic degeneration of hepatocytes (A) with extrusion of the pyknotic nucleus produces the Councilman body.

38.
The answer is E, C, A. The metabolic effects of alcohol on hepatocytes responsiblefor fatty change are reversible if alcohol is stopped. This is the earliest feature of alcoholic
liver damage.

The site of earliest damage in alcoholic liver disease is around the terminal hepaticvein (centrilobular); hepatocyte necrosis in this area is very suggestive of alcohol damage.

Before cirrhosis can be present hepatocyte regeneration has to occur, along with fibrosis; fibrosis on its own is not cirrhosis. Ground glass hepatocytes (B) are a feature ofhepatitis B infection. The portal areas (D) are affected later in alcoholic hepatitis whenextensive damage has occurred and when cirrhosis is present.

39.
The answer is B. Portal hypertension (usually caused by cirrhosis) results from interference with the hepatic micro-circulation such that vessels in the portal-systemicanastomotic system become engorged and develop varicosities. This occurs most spectacularlyin the oesophagus, and rupture of these veins is a common cause of death in alcoholics.

40.
The answer is E, B, C. Patients with ulcerative colitis may develop sclerosing cholangitis which is associated with the development of cholangiocarcinoma. In the Far Eastinfection by river fluke causes cholangiocarcinoma.

Exposure to vinyl chloride monomer is implicated in the development of haemangiosarcoma.

Oral contraceptive and sex hormone therapy have been associated with the development of liver cell adenomas which are benign liver cell tumours.

The commonest primary liver cell tumour (A) is the hepatocellular carcinoma. The hepatoblastoma is a liver tumour of childhood (D).

44.
The answer is B. Chronic pyelonephritis (C) result in systemic hypertension (E) with left ventricular hypertrophy (A); hypertension is associated with increased risk of atheromaand thrombotic occlusion of a coronary artery (B) which causes myocardial infarction,complicated by necrosis of the left ventricular wall and eventual rupture (D).