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USMLE Step 1 > UWorld_3.2 > Flashcards

Flashcards in UWorld_3.2 Deck (15)
1

Type I collagen: locations, assoc. diseases

  • locations
    • dermis
    • bone
    • tendons, ligaments
    • dentin
    • cornea
    • blood vessels
    • scar tissue
  • assoc. disease
    • osteogenesesis imperfecta

2

Type II collagen: locations

  • cartilage
  • vitreous humor
  • nucleus pulposus = inner core of the vertebral disc

3

Type III collagen: locations, assoc. diseases

  • locations
    • skin
    • lungs
    • intestines
    • blood vessels
    • bone marrow
    • lymphatics
    • granulation tissue
  • assoc. diseases
    • Ehlers-Danlos syndrome (types 3 & 4)

4

Type IV collagen: locations, assoc. diseases

  • location
    • basement membranes
  • assoc. diseases
    • alport syndrome

5

TATA box = 

  • promoter region of euk. genes that binds transcription factors and RNA polymerase II during initiation of trxn
  • located approx. 25 bases upstream of beginning of coding region

6

Purpose of analysis of variance

  • t-test = compare the difference (i.e. is there a true difference?) between the means of 2 groups
  • AOV = compares difference between the menas of 2+ groups

7

  • Purpose of Chi-square test
  • Purpose of Multiple linear regression
  • Purpose of Pearson correlation coefficient

 

  • statistical analysis used to check for an association between 2 categorical variables
  • MLR = model linear relationship between a dependent variable and 2+ independent variables
  • PCC = measure the strength and direction of a linear relations between 2 variables

8

Common finding in MG

  • MG ==> m. weakness
    • extraocular muscles most commonly affected
    • ==> ptosis & diplopia
    • sx worse w/activity or @ end of the day
  • majority found to have thymoma or thymic hyperplasia ("mediastinal mass")

9

Cholesterol, bile salts, and phosphatidylcholine impacts on gallstone formation

  • high cholesterol ==> increased risk
  • bile salts + phosphatidylcholine increase cholesterol solubilty
    • high bile/phosph ==> lower risk
    • low bile/phosph ==> higher risk

10

V. cholera characteristics

  • oxidase-positive, gram (-), comma-shaped; able to grow on high-alkaline media
  • ==> diarrhea via enterotoxins or by invading/damaging intestinal epithelium
    • does not invade mucosa and cause enterocyte death
  • cholera toxin (also @ ETEC) ==> activation of adenylate cyclase ==> increased cAMP production ==> increased chloride efflux and decreased sodium reabsorp ==> watery diarrhea
    • "rice water diarrhea" = flecks of mucous and epithelial cells
      • no leukocytes or erythrocytes

11

Watery diarrhea: mechanism, stool findings, causes

  • mechanism = non-inflammatory (enterotoxin)
  • stool
    • no leukocytes
    • no red cells (blood)
  • causes
    • V. cholera
    • ETEC
    • Bacillus cereus
    • S. aureus (pre-formed toxin in early food poisoning)
    • Giardia, other parasites
    • some viruses

12

Dysentery diarrhea: mechanism, stool findings, causes

  • mechanism = inflammatory (invasion or cytotoxin)
  • stool
    • PMNs
    • +/- RBCs (blood)
  • causes
    • shigella
    • salmonella
    • C. jejuni
    • EIEC
    • Yersinia enterocolitica
    • C. difficile
    • Entamoeba histolytica

13

Enteric fever diarrhea: mechanism, stool findings, causes

  • mechanism = penetration and possible dissemination
  • stool
    • mononuclear leukocytes
  • causes
    • salmonella typhi (thyphoid fever)

14

~Normal cardiac pressures

  • "nickel, quarter, dime dollar"

15

Tx for severe asthmatics 

  • anti-IgE drugs to help reudce allergy triggers of asthma
  • e.g. Omalizumab ==> patients w/mod-severe allergic asthma
    • IgG1 monoclonal antibody
    • binds to IgE to prevent action of IgE w/its receeptor on mast cells ,basophils and other cells

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