test #31 4.20 Flashcards Preview

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Flashcards in test #31 4.20 Deck (119)
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1

posteroinferior wall of left ventricle supplied by.. infarct on ECG?

posterior descending branch of RCA.

ST elevations in leads II, III, aVF

2

transmural ischemia of interventricular septum on EKG?

ST elevation in leads V1 V2

3

transmural ischemia of anterior left ventricular wall on EKG?

ST elevation in V3 V4

4

occlusion of proximal LAD infarcts.. causes on EKG?

infarts anteroseptal transmural ischemia. ST elevations in V1-V4

5

anterolateral infarct of left ventricle on EKG?

LCX or LAD -- V4-V6

6

lateral wall of left ventricle infarct on EKG?

I, aVL & V5-V6

7

which segment of intestine is always involve w/ hirschsprung? why?

rectum, bc ganglion cells of submucosa & myenteric plexi travels caudally.

aganglionic segment -> constricted bc cannot relax

8

torsades

form of ventricular tachycardia.

polymorphic QRS complexes of varying amplitudes and cycle length.

give appearance that the tip of QRS is twisting around ECG baseline.

always associated w/ underlying prolonged QT

9

prolonged QT caused by..

class IA and III antiarrhythmics
(not amiodarone)
phenothiazines
TCAs

10

lidocaine fxn by..

blocking Na+ channels

11

penicillins are structurally stimilar to

terminal d-ala-d-ala of peptidoglycan molecule

blocks transpeptidase

12

N-acetylmuramic acid and N-acetylglucosamine are

peptidoglycan precursor molesules of cell wall in bacteria

13

sulfonamide antibiotic mechanism? trimethoprim

sulfonamides: compete w/ PABA (paraaminobenzoic acid) for incorporation into folic acid..

trimethoprim: block dihydrofolate reductase

14

staph epidermidis infxn?

rx:

major cause of infection in pts w/ indwelling catheters or implanted foreign bodies.

produces biofilm (polysaccharide slime) allows adhesion.

diagnosis: recover from mult cultures (can be contaminant)

rx: initial aggressive. vancomycin w/ rifampin or gentamycin or both.

can be resistant to methicillin

15

rx for staph epidermidis bactermia. if not..?

aggressive! vancomycin + rifampin + gentamycin

w/o rx: indolent endocarditis after valve replacement. intracardiac abscess formation, dehiscence of prosthetic valve, septic embolization

16

AML blasts will stain positive for

peroxidase (since Aur rods have MPO)

17

TdT in lymphocytes

terminal deoxynucleotidyl tranferase

add nucleotides to V D J regions of Ab gene for diversity.

mature of immature B and T cells

18

hairy cell leukemia stains. what type of cells are they?

TRAP (tartare resistant acid phosphatase)

B-cells! CD20+

splenomegaly, fatigue, pancytopenia

19

glomus body & glomus tumor

small, encapsulated neurovascular organ. temp regulation

in dermis of nail bed, pads of fingers & toes, ears

afferent arteriole --> richly innervated, muscular arteriovenous anastomosis --> efferent vein.

role:

COLD: shunt blood AWAY from skin surface: prevent heat loss
HEAT: direct blood TO skin, facilitate dissipation of heat.

form PAINFUL tumors under fingernail. arises from modified smooth muscle cells.

20

skin presentation of histiocytosis

erythematous papules, nodules, and/or scaling plaques

21

electrolyte presentation of primary adrenal insufficiency (Na, K, Cl, HCO3)

low Na
high K
low Cl
low HCO3

22

primary adrenal insufficiency vs. secondary / tertiary (i.e. pituitary / hypothal)

primary -- loose aldosterone, cortisol, and androgens

secondary -- loose cortisol only. aldosterone triggered by renin / angiotensin system!

23

Na+ in hyperaldosterone?

initial increase, but aldosterone loss --> intravascular hypervolemia --> ANP --> diuresis & compensatory Na+ loss

24

why is supraspinatus injury most common of rotator cuff?

repeated impingement trauma between humeral head & acromion

abbductor

25

subacromial bursa location

under both acromion/clavicle & tendon of deltoid muscle.

sits on top of supraspinatus

26

why no hep C vaccine // why prone to chronic infection

variety in antigenic structure of HCV envelope proteins

1. multiple genotypes & subgenotypes
2. hypervariable region of envelope glycoprotein -- prone to frequent mutation
3. no proofreading 3-5' exonuclease

constantly emerging mutant strains &much variety in a single person at one time

27

positive trendelenburg sign

hip dips to unaffected side when standing on affected sign (failure of gluteus medius/minimus to pull pelvis down and abduct thigh) --> superior gluteal n.

28

sciatic n. innervates all knee flexors except..

biceps femoris

29

Tzanck prep

Wright-Giemsa stain on epithelial cells scraped from ulcer base.

see multinucleated giant cells w/ some intranuclear inclusions -- HSV & VZV

30

primary vs. reactivation HSV-1 infxn

recurrent:
-usu one side
-much less extensive area involved (limited)
-favor skin around mucosal orifice (lips & nose)

-bilateral
-larger area
-gingivostomatitis: gums & oral mucosa