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Oral Medicine
The aortic valve is located between the left ventricle and the aorta and is responsible for preventing the backflow of blood into the left ventricle during systole, ensuring that blood is efficiently pumped out of the heart into the systemic circu
General Microbiology
the Vi antigen of S. typhi confers upon the bacterium Resistance to phagocytosis. The Vi antigen is a polysaccharide capsule that protects the bacteria from being engulfed and destroyed by phagocytic white blood cells, contributing to its virulence.