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Flashcards in usmle2: block 3 Deck (67)
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1

most common cause of epididymitis in heterosexual male

c. trachomatis

(homosexual: colon bacterias)

2

what drug can be given w/ penicillin to inhibit metabolism / secretion

penicillin + probenicid

prevents reabsorption of uric acid
prevents secretion of penicillin

3

bloom syndrome

photosensitivty, short stature, erythema, teleangiectasia

defect in DNA helicase RecQL3

predisposed to lymphoproliferative & GI malginancy

4

where does heriditary nonpolyposis colon cancer usu arise

microsatellite instability
mismatch repair defect

usu proximal bowel

5

waxing & waning lymphadenopathy

follicular lymphoma
bcl-2 t(14,18)

small cleave w/o nucleoli &
large cell w/ mult nucleoli

6

burkitt lymphoma in industrialized country location

ascites & abdominal mass

distal ileum, cecum, mesentary

7

Dupuytren's contractures

fixed flexion of fingers
physical manifestation of high estrogen in cirrhotic patients

8

what are lisch nodules

pigmented iris hamartomas

9

what's in a neurofibroma

schwann cells, fibroblasts, neurites

10

niacin mechanism

block hormone sensitive lipase --> reduce formation of VLDL and triglyerides

increases HDL
decrease TG

11

possible niacin side effects

prostaglandin mediated:
flushing, pruitis, headache

12

how many of the oocytes we are born w/ remain at puberty?

25%
of that, only 400 will be ovulated normally
rest = atesia

13

describe follicular atresia (oocytes)

outside basal lamina: THECA cells dedifferentiate & return to poor of ovarian interstitial or stromal cells

in basal lamia: OOCYTE & GRANULOSA cells = apoptosis

14

which antibiotics are teratogen (2)

aminoglycoside "a mean guy hit the baby" CN VIII toxicity

tetracycline: discolored teeth

15

which antiseizure drugs are teratogen (3)

carbamazepine, phenytoin, valproate (inhibit folate reabsporption

PVC

16

which anti-thyroid drug is a teratogen

methimazole

17

loss of heterozygosity

relevant to oncogenesis

person born w/ single defective copy of tumor supressor gene does not develop malignancy until some cells spontaneously mutate other gene

18

reason diff alleles have different cuts on restriction enzyme digestion?

single nucleotide polymorphisms at restriction enzyme cleavage site

19

how does paclitaxel in a drug-eluting stent work?

prevents intimal hyperplasia
(major cause of restenosis)

20

after placing a coronary stent, what is the major cause of restenosis?

intimal hyperplasia
prevent w/ paclitaxel / sirolimus
freeze cells in metaphase

21

anti-platelets post stent?

given LONGER w/ drug-eluting stents (paclitaxel) bc the rate of endolthelium reformation delayed.

less time w/ bare metal stents

22

which RNA viruses replicate in nucleus?

- retroviruses (HIV, HTLV)
- influenza

23

where does influenza replicate

nucleus! (+ HIV) all other rna virus = cytoplasm

24

most common cause of pneumonia in infant

RSV

25

croup & bronchiolitis in children
bronchitis in adult

parainfluenza birus

26

which GLUT is insulin dependent? which tissues

GLUT 4: muscle & adipocytes

27

what 2 muscles pull on acromial-end of clavicle? medial portion (3)

lateral:
1. deltoid
2. trapezius

medial
1. pec major
2. sternocleidomastoid
3. sternohyoid

28

Ras is downstream

GTP-binding protein
downstream RTK
-single transmembrane, dimerize on binding

(not GPCRs)

29

differential of orotic aciduria?

1. if also hyperammonia: OTC
build up of carbamoyl phosphate --> shunt to de novo pyridamine synthesis --> orotic acid temp base

2. w/o hyperammonia --> orotic aciduria

30

steps of collagen formation

in ER:
hydroxylation of proline/lysine
glycosylation of some lysine
assembly of triple helix = PROCOLLAGEN
--requires 1. H bonding of hydroxylated groups & 2. disulfide bonding w/ C-terminals

secrete procollagen into golgi -> out of cell

in ECM
cleave N & C terminus -> collagen fibril
crosslink via lysyl oxidase