Under the

condition of emotional excitement, the heart rate of a 30-year-old person

increased to 112 bpm (=beats per minute). Which part of the cardiac conduction

system is responsible for this?

Which primary gastrointestinal hormones experience reduced secretion

following duodenal removal?

X-ray

examination of a patient revealed pulmonary emphysema. What is the reason for

dyspnea (=shortness of breath) development?

A 2-year-old child experienced convulsions due to

Among

neurohormones, there is only one hormone that belongs to the derivatives of

amino acids according to the classification. Specify the hormone:

The sterile

Petri dishes and pipettes are necessary to prepare for microbiological tests in

a bacteriology laboratory. Which method of sterilization should be applied in

this case? 

The blood

sample of a patient revealed the signs of HIV infection. Which cells does HIV primarily affect?

A man died 8 days after the onset of the disease. He was

diagnosed with dysentery. On the autopsy, a thickened wall of the sigmoid colon

and rectum was found. There was a fibrinous membrane covering the surface of

the mucous membrane. Histologically, profoundly penetrating necrosis of the

mucous membrane was observed. Necrotic masses were infiltrated by fibrin. What

type of colitis did the patient have?

Having conducted a post-mortem examination of the

58-year-old man, the doctor discovered a deformed and thickened mitral

(bicuspid) valve, preventing complete closure. Under the microscope, the

centers of collagen fibers were eosinophilic with a positive fibrin reaction.

What is the most likely diagnosis? 

At the autopsy of a

40-year-old woman suffering from rheumatic arthritis, the doctor revealed an

enlarged dense spleen. When dissected, its tissue was mahogany-coloured with

enlarged follicles, resembling semi-transparent grayish-whitish grains. What

pathological process is the most likely?