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Flashcards in UWorld_2.25 Deck (11)
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1

Biostats:

type I error = 

type II error =

power =

  • type 1 (a) = probablity of seeing a difference when there is no diffence in realtiy
    • a = p-value
  • type 2 (B) = probablity of concluding that there is no difference between the groups when one truly exists
  • power = ability of study to differentiate between two groups
    • power = 1 - B

2

Drug effects:

tachyphylaxis = 

additive =

synergistic = 

permissive = 

  • tachy = decreased drug response w/repeated administration
  • additive/synergistic = two drugs with similar actions
    • additive = admin of both is equal to the sum of the effects
    • synergistic = admin of both leads to effects exceeding the sum of the drugs individually
  • permissive = admin of a different type of drug (without its own action @ desired site) leads to increased action of an effective drug if given together

3

Klinefelter presentation

  • 47 XXY
  • hypogonadism
    • seminferous tubules destroyed and hyalinized ==> small, firm testes
    • leydig cells damaged ==> low T + erectile dysfxn
    • low T + low inhibin ==> elevated FSH/LH
    • ==> infertility
  • long limbs (delayed epiphyseal fusion)

4

Immune rxn to live polio vaccine vs. killed polio vaccine

  • both ==> IgG immunity against polio
  • live = oral admin ==> production of oropharyngeal and duodenal IgA
  • killed = no IgA response

5

AChE in amniotic fluid ==> dx?

  • Neural tube defects = failure of fusion of neural tube during 4th week of fetal development
  • ==> leakage of fetal CSF ==>
    • elevated alpha-fetoprotein
      • crosses placenta ==> elevated alpha-fetoprotein @ mother serum
    • acetylcholinesterase 

6

Congenital disease due to:

embryonic migration abnormality

failed apoptosis

  • migration ==> hirschsprung's disease
    • intenstinal wall lacks nerves
  • apoptosis ==> duodenal atresia = failure of recaalization during fetal development

7

Iodine transport @ thyroid

  • sodium-iodide symporter brings iodine into thyroid against concentration gradient
  • NIS is also responsible for transporting perchlorate and pertechnetate into thyroid 
    • if potassium perchlorate is present ==> competitive inhibition

8

Drugs that interfere with iodine uptake

  • antithyroid thionamides
    • methimazole ==I thyroid peroxidase ==> blocked conversion of iodide to iodine
    • propylthiouracil
  • usually stopped 7-10 days before tx w/radioactive iodine for hyperthyroidism

9

EBV associated with....

  • Hodgkin's and Non-Hodgkin's lymphoma
  • EBV Burkitt's lymphoma
  • nasopharyngeal carcinoma

10

Prolonged exposure to loud noise ==>

  • hearing loss due damage of the sterociliated hair cells @ Organ of Corti
  • noises > 85dB ==> distortion/fracture of sterocilia due to shearing forces against tectorial membrane

11

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