Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

UWorld > Block 5 > Flashcards

Block 5 Flashcards

1
Q

What type of bone does osteoporosis primarily involve? What findings will you see?

A

Primarily involves trabechular (spongy/cancellous) bone

You will see trabechular thinning with fewer interconnections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What disease presents with thymus abnormalities, such as thymoma, thymic hyperplasia and extraocular muscle weakness?

A

Myasthenia gravis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is confounding?

A

When a perceived association between an exposure and an outcome is actually explained by a confounding variable associated with both the exposure and the outcome

(example: kids and shoe size, IQ, confounding = age)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What method is generally used in the design stage of case-control studies to control confounding?

A

Matching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do you see after 12-48 hours of inadequate blood flow to the brain?

A

“red neurons”

eosinophilic cytoplasm, puknotic nuclei, loss of Nissl substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do you see after 24-72 hours of inadequate blood flow to the brain?

A

necrosis and neutrophilic infiltration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do you see after 3-5 days of inadequate blood flow to the brain?

A

macrophage infiltration and phagocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do you see after 1-2 weeks of inadequate blood flow to the brain?

A

reactive gliosis, vascular proliferation –> liquefactive necrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do you see after >2 weeks of inadequate blood flow to the brain?

A

glial scar –> cystic area surrounded by gliosis (>1 month)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Do NK cells express CD4, CD8, or CD3 molecules on their surface?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Do NK cells express either CD16 or CD56?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Do NK cells require the thymus for maturation?

A

No, they are present in athymic patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Do NK cells have antigen-specific activities or require exposure to antigen for activation? Do they possess antigen meory ability?

A

NO to all of those things

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Are NK cells activated by interferon-gamma and IL-12?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What nutritional changes related to the pancreas may occur in severe CF?

A

Severe CF may cause total obstructino of pancreas followed by complete fibrotic atrophy of exocrine glands –> deficiency in fat soluble vitamins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What vitamin is a nueroprotective agent that may slow functional losses in Alzheimer’s?

A

Vitamin E (a-tocopherol)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What may avitaminosis A contribute to?

A

Squamous metaplasia of the epithelial lining of pancreatic exocrine ducts, which are already injured and predisposed to squamous metaplasia by inspissated mucus (thickened)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

normal levels of what vitamin are required to maintain orderly differentiation of specialized epithelia, including mucus-secreting columnar epithelium?

A

vitamin A

when a deficiency state exists, the epithelium undergoes squamous metaplasia to a keratinizing epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

which bacteria can destroy RBCs through cold-aggultinins, leading to mild anemia and also cause Stevens-Johnson syndrome & joint pains?

A

mycoplasma pneumonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens to patients with galactosemia and galactitol accumulation?

A

galactitol accumulates in the lens of patients and causes osmotic damage leading to cataract formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How is galacticol formed?

A

from excess circulating galactose in galactosemia by aldose reductase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where does the PCL attach?

A

Inferior to the posterior part of the intercondular area of the tibia and the anterior part of the lateral surface of the media epicondyle of the femur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What a Kerley B lines and when are they seen?

A

They are seen on the xrays of pts with left heart failure

Short horizontal lines situated perpendicularly to the pleural surface that represent edema of the interlobular septa

24
Q

In A fib, what regulates the number of atrial impulses that reach the ventricle and determines the ventricular contraction rate?

A

AV node

25
Q

How does glucose influence the lac operon?

A

increased glucose results in decreased expression of the lac operon

26
Q

How is the lac operon positively regulated?

A

It’s positively regulated by the binding of catabolite activator protein (CAP) to a site slightly upstream from promoter regions

This only occurs when cAMP concentrations are high

Glucose decreases activity of adenylyl cyclase –> decreased cAMP, regpressing lac operon

27
Q

What causes increased lung elastic recoil leading to airway thickening due to increased outward pulling (radial traction) by the surrounding fibrotic tissue?

A

interstitial lung diseases, which cause progressive pulmonary fibrosis with thickening and stiffening of the pulmonary interstitium

28
Q

What bacteria is a blood-loving organism that requires both X factor (hematin) and V factor (NAD+) to grow?

A

H. influenzae

29
Q

What adrenal enzyme deficiency impairs the synthesis of androgens, estrogens, and cortisol but does NOT inhibit mineralocorticoid production?

A

17a-hydroxylase deficiency

30
Q

What do boys with 17a-hydroxylase deficiency present with?

A

Boys appear phenotypically female at birth but lack internal female genetalia due to the absence of virilizing androgens in utero

31
Q

What do females with 17a-hydroxylase deficiency present with?

A

Females develop normal internal and external genetalia

32
Q

What electrolyte abnormalities may be seen around puberty with 17a-hydroxylase deficiency?

A

Excessive production of mineralcorticoids by adrenals results in hypertension, hypokalemia, and low renin levels

33
Q

What is the immediate treatment for someone poisoned with rodenticides?

A

Rodenticides contain brodifacoum, a long acting 4-hydroxycoumarin derivative

Immediately treat with fresh frozen plasma and vitamin K to prevent coagulopathy and abnormal bleeding

34
Q

What factors does FFP replenish? What factors does cryoprecipitate replenish?

A

FFP = factors 2, 7, 9, 10

cyroprecipitate = factors 8, 13, vWF, and fibrinogen

35
Q

What are the sizes of petechiae, purpurae, and ecchymoses?

A

Petechiae = less than 5 mm

Purpurae = 5 mm - 1 cm

ecchymoses = >1 cm

36
Q

What does IGF-1 mediate and where/how is it produced?

A

IGF-1 mediates growth-promoting effects from GH

released from the liver following a stimulation of hepatic GH receptors and subsequent activation of the JAK-STAT signaling pathway

IGF-1 binds to a specific receptor tyrosine kinase found on cells throughout body to stimulate growth

37
Q

What is the most abundant amino acid in collagen?

A

glycine

triple helix = (-Gly-X-Y)333

38
Q

What drugs, administered with statins, will cause increased incidence of myopathy and rhabdomyolsysis leading to acute renal failure?

A

statins are metabolized by cytochrome P-450 3A4 (with exception of pravastatin)

administratino of 3A4 inhibitors (macrolides) will increase SE’s

39
Q

What should HIV patients with CD4+ counts <50 cells/uL be administered to prevent MAC (mycobacterium avium complex) infection?

A

prophylactic azithromycin

40
Q

What is mycobacterium avium complex?

A

MAC is a common opportunistic pathogen that causes disseminated disease in HIV+ patients

presents with pallor, hepatosplenomegaly, clear chest X-ray, elevated alk phos and lactate dehydrogenase

culture grows optimally at 41 degrees C (to differentiate from M. tuberculosis)

41
Q

What cardiac defects are associated with DiGeorge syndrome?

A

Tetralogy of Fallot

interrupted aortic arch

42
Q

This 22q11.2 deletion causes thymic aplasia, failure of parathyroid formation due to defective development of 3rd and 4th pouch

A

DiGeorge Syndrome

43
Q

What lab abnormality and infection history do pts with DiGeorge syndrome present with?

A

hypocalcemia tetany (no PTH)

recurrant viral and fungal infections (no T-cells)

44
Q

What lab abnormality is caused by administration of ACE inhibitors with K+ sparing diuretics?

A

profound hyperkalemia

45
Q

Amiloride, triamterene, and spironolactone are all…

A

K+ sparing diuretics

46
Q

vaginal agenesis aka Mullerian aplasia

A

no upper vagina (short vagina) and variable uterine development

XX females with normal ovaries and therefore secondary sexual characteristics

47
Q

androgen insensitivity syndrome

A

pts are 46,XY males who appear phenotypically female due to an androgen receptor defect

pts have minimal axillary or pubic hair due to androgen resistance

pts have cryptorchid testes (absent from scrotum) and no uterus or ovaries

48
Q

Kallman syndrome

A

occurs due to decreased synthesis of GnRH in the hypothalamus

although females are rarely affected, those with the condition present with primary amenorrhea, no secondary sex characteristics, and an olfactory sensory defect

49
Q

Klinefelter syndrome

A

47,XXY

affects males and is characterized by tall stature, poorly developed secondary sex characteristics, atrophic testes, and infertility

50
Q

Turner syndrome

A

45,X

a common cause of primary amenorrhea

affect individuals have short stature, webbed neck, shielded chest, and “streaked” or fibrotic ovaries

usually don’t develop secondary sex characteristics

51
Q

HIV patient with abdominal distention and anorexia, ascites and a large mass surrounding the small intestine

biospy reaveals uniform, round, medium-sized tumor cells with basophillic cytoplasm and a proliferation fraction (Ki-67 fraction) of >99%

A

Burkitt lymphoma

52
Q

balanced t(8;14) translocation, which causes over expression of c-MYC, a transcriptional regulator that controls cell proliferation

A

Burkitt lymphoma

53
Q

What effect do chronic EBV and increased B-cell proliferation have on c-MYC translocations?

A

increased risk of c-MYC translocations

54
Q

what symptoms cannot be corrected in severe thiamine deficiency?

A

memory and learning abnormalities usually persist as Korsakoff syndrome: damage to the anterior and dorsomedial thalamic nuclei

55
Q

the power of a study is…

A

the probability of seeing a difference when there is one

Power = 1-beta, where beta is the Type II error rate

56
Q

Characterized by the abnormal proliferation of mast cells and increased histamine secretion

Histamine increases production of gastric acid by parietal cells

syncope, flushing, hypotension, tachycardia, bronchospasm, pruritis, urticaria, dermatographism (skin writing)

A

systemic mastocytosis

UWorld (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions