Random USMLE Facts volume 2-2

Rahul's Noteblog Notes on USMLE facts, Exam Tips, and USMLE Lab Values Random USMLE Facts volume 2-2

Random USMLE Facts volume 2-2:

USMLE Facts 1	USMLE Facts 2	USMLE Facts 3	USMLE Facts 4	USMLE Facts 5
USMLE Facts 6	USMLE Facts 7	USMLE Facts 8	USMLE Facts 9	USMLE Facts 10

What are the driving forces behind angiogenesis?

Vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF).

What is the pathology of erythroblastosis fetalis?

• Caused by maternal anti-fetal erythrocyte antibodies.
• These maternal antibodies cross the placenta.
• There may be extramedullary hematopoiesis in many infant tissues.

What are the findings in tibial nerve injury?

Difficulty walking; foot is dorsiflexed and everted; inability to stand on tiptoes; sensory loss on plantar foot.

What may be the cause of breathlessness and wheezing in asthma patients?

This is chronic eosinophilic bronchitis and involves eosinophils activated by IL-5.

What may be a cause of worsening cough in smokers?

AAT-deficiency and associated emphysema. Lung volume may increase and diffusing capacity may decrease.

What kind of test is done in order to monitor the intestinal brush border absorptive function independently of pancreatic function?

D-xylose absorption test.

Where exactly does ADH (vasopressin) act?

Medullary segment of the collecting duct. It acts on V1 and V2 receptors.

Explain the actions of the medullary respiratory center:

Respiratory rate is maintained by the medullary center. Input comes from the central and peripheral chemoreceptors and airway mechano-receptors. Central chemoreceptors respond to changes in pH and peripheral chemoreceptors (carotid and aortic bodies) respond to hypoxia.

What is the cause of a midgut volvulus?

Impaired midgut rotation around the superior mesenteric artery causing intestinal obstruction.

What is the function of neurophysins?

Carrier proteins for oxytocin and vasopressin (ADH).

What are the epithelial differences between true and false diverticuli?

False diverticuli consists of mucosa and submucosa; true diverticuli consists of mucosa, submucosa, and muscularis. An example of true diverticulum would be a Meckel's diverticulum.

Describe a cryptococcus neoformans:

• Infects HIV patients.
• Staining of bronchoalveolar fluid reveals yeast forms.
• Causes meningitis.

ACE inhibitors taken with what drugs can cause hyperkalemia?

Potassium sparing diuretics like amiloride, triamterene, and spironolactone.

What is the action of benzodiazepines on GABA receptors?

There are three types of GABA receptors: A, B and C. Benzodiazepines act on type A and initiates an inhibitory action of GABA within the brain. The binding activates an ion channel and causes neuron re-polarization.

Besides glucose, what other factors are involved in insulin secretion?

Parasympathetic and sympathetic nerve cells that innervate beta cells. Parasympathetic system causes insulin secretion by the smell/sight of food. Sympathetic system may have an inhibitory or stimulatory effect on insulin secretion - alpha adrenergic receptors inhibit and beta-adrenergic receptors stimulate insulin release.

What are the physical findings in beta-thalassemia?

Chronic hemolysis and chipmunk facies.

What are the findings in neuroblastoma?

Non-rhythmic conjugate eye movements associated with myoclonus (opsoclonus myoclonus syndrome) and an abdominal mass.

USMLE Facts 1	USMLE Facts 2	USMLE Facts 3	USMLE Facts 4	USMLE Facts 5
USMLE Facts 6	USMLE Facts 7	USMLE Facts 8	USMLE Facts 9	USMLE Facts 10

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