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Free USMLE – United States Medical Licensing Examination Practice Test Question

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Showing 13–15 of 20 questions

Question 13

Which of the following amino acids can function as a neurotransmitter in the CNS?

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    Leucine
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    Glutamic acid
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    Lysine
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    Valine
Question 14

A 55-year-old hypertensive man develops sudden onset of excruciating pain beginning in the anterior chest, and then radiating to the back. Over the next 2 hours, the pain moves downward toward the abdomen. Which of the following is the most likely diagnosis?

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  • ○

    Aortic dissection
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    Syphilitic aneurysm
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    Aortic valve stenosis
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    Atherosclerotic aneurysm
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    Myocardial infarction
Question 15

Which of the following is not a characteristic of MS?

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    Nystagmus
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    Elevated IgE levels
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    Optic neuritis
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    Tremors