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Flashcards in UWorld_2.9 Deck (14)
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1

Failure of fusion of urethral folds in female and male==> ?

  • @ female = normal ==> vaginal opening
  • @ male = abnormal ==> hypospadia
    • urtheral folds normally form ventral portion of penis
    • failure of fusion ==> urethral opening on ventral surface somewhere between perineum and just proximal to glans penis

2

Epispadia presentation

  • location of urethral opening on dorsal surface of penile shaft
  • due to malpositioning of genital tubercle during 5th week of gestation

3

Characteristics of kinesin and dynein

  • microtubule-associated motor proteins fxn of rapid transport of materials/organelles in cells
  • @ neurons:
    • kinesin = anterograde transport
    • dynein = retrograde transport
  • dynein also associated w/ciliary and flaggelar movement
  • energy for movement derived from ATP

4

Common proto-oncogenes + gene product + associated cancer

  • RAS = GTP-binding protein
    • Choliangiocarcinoma
  • MYC = transcription factor
    • Burkitt's Lymphoma
  • ERBB-1 (EGFR) = receptor tyrosine kinase
    • Lung adenocarcinoma
  • ERBB-2 (HER2) = receptor tyrosine kinase
    • Breast Cancer
  • ABL = nonreceptor tyrosine kinase
    • chronic myelogenous leukemia
  • BRAF = RAS signal transduction
    • Hairy cell leukemia
    • melanoma

5

Common tumor-suppressor genes + gene product + associated cancer

  • BRCA-1, BRCA-2 = DNA repair gene
    • Breat & Ovarian cancer
  • APC/B-catenin = WNT signaling
    • colorectal, gastric, pancreatic cancer
    • FAP
  • TP53 = genomic stability
    • most cancers
    • Li-Fraumeni
  • Rb = inhibits G1/S transition
    • Retinoblastoma
    • Osteosarcoma
  • WT1 = urogenital differentiation
    • Wilm's tumor
  • VHL = ubiquitin ligase component
    • von-hippel lindau

6

Blood gas levels during aerobic exercise

  • homeostatic mechanisms maintain arterial O2/CO2/pH
  • increased O2 consumption @ muscles + increase CO2 production ==> decreased O2 and increased CO2 @ mixed venous blood

7

Location of B cell VDJ recombination + post-activation location

  • VDJ recombination ==> formation of antibodies/antigen recognition; occurs during maturation @ bone marrow
  • Activated B-cells ==> germinal centers of lymph nodes
    • proliferation of B-cells into memory cells and antibody secreting cells
    • antibody-secreting cells undergo isotype switching

8

Characteristics of horshoe kidney

  • horshoe kidney = fusion of kidneys at upper or lower pole (90% at lower pole)
  • kidneys normall ascend from sacral area ==> 
  • in horshoe kidney, fused pole lies anterior to great vessels
    • fused poles become trapped by inferior mesenteric artery and cannot ascend to normal position
  • can lead to urinary tract obstruction and hydronephrosis

9

Causes/location of osteomyletis in childhood

  • s. aureus
  • long bones

10

Causes/location of osteomyletis in sickle cell disease

  • salmonella
  • s.aureus
  • @ long bones

11

Causes/location of osteomyletis in Pott disease

  • mycobacterium tuberculosim
  • @ vertebrae

12

Cause/location of osteo in DM

  • polymicrobial
  • @ bones of foot (from foot ulcers)

13

Causes/location of osteo @ recumbent patient

  • polymicrobial
  • @ sacrum/heels

14

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