UWorld Practice Test #1 Flashcards
(36 cards)
What is the relative speeds of the electrical signal within the heart. Where is it fastest and where is it slowest?
Park AT VENtricular AVenue
Purkinje…Atria…Ventricles…AV Node
Bone tumor associated with Paget Disease
Osteosarcoma
-remember that this is destruction of normal trabellular bone pattern, mixed radiodensities, periosteal new bone formation, lifting of the cortex, and Codman’s triangle
Bimodal distribution
Seen on metaphasis of long bones (unlike ewing which is in diaphysis)
Globus sensation in throat
- common abnormal sensation of a foreign body, tightness, or fullness in the throat. It often worsens when swallowing saliva and may be aleviated when swallowing food
- It is a functional disorder, there is no structural defect
- Frequently associated with anxiety or other underlying psych issues
“Lump in your throat”
DNA laddering
DNA fragments in multiples of 180bp is a sensitive indicator of apoptosis
-A hallmark of cancer is the ability to evade apoptosis, particularily the intrinsic (mitochondrial) pathway of apoptosis (seen in BCL2 overexpression in t(14;18) follicular lymphoma)
What is drug X and drug Y
Drug X must be ACh since when it is combined with Phyostigmine (an AChE-I, the effect is increased).
Thus, drug Y must be a muscarinic antagonist, and the most likely drug would be Atropine (results in decreased muscle contraction)
-Ipatroprium and Tiotroprium work via similar mechanisms and could be Y as well.
What does this pt have and what are some common features?
Acute Promyelicytic Leukemia (APL) which is a translocation of t(15:17). See auer rods
tx: all-trans retinoic acid
What cytokine is produced exclusively by lymphocytes
IL-2 produced exclusively by antigen stimulated T-cells
NOT:
IL-1 –> produced by mononuclear phagocytes
TNF-alpha –> produced by macrophages
INF-alpha –> produced by macrophages, NK, monocytes, B-cells
What is this lesion and what would you see histologically?
Molluscum Contageiosum. The papulles are pruritic and have umbilicated centers
Caused by the poxvirus. Transmitted through direct contact or fomites
Under microscope will see epidermal hyperplasia along with molluscum bodies. These will be filled with large eosinophilic cytoplasmic inclusions of viral particles
Key defense mechanisms. LEARN THEM!!!
Acting out
Denial
Displacement
Intellectualization
Passive Agressive
Projection
Rationalization
Reaction formation
Regression
Splitting
Sublimation
Suppression
Label the parts of this image and where does Sildalfinil work?
A: tunica albuginea (Buck fascia)
B: corpus cavernosum
C: deep fascia
D: Corpus spongiosum
E: urethral lumen
What organ secretes like this?
This is the exocrine pancreas
Contains fixed concentrations of Na and K that are virtually identical to those of the plasma
Levels of bicarb and Cl vary with pancreatic flow rate (which increases in response to secretin)
The inverse relationship of bicarb and Cl is due to a chloride bicarb exchanger on the apical surface of ductal cells
PTSD vs Acute stres disorder
PTSD >1 month
ASD > 3 days < 1 month
Relative Risk calculation
The risk in exposed subjects vs the risk of unexposed subjects
RR= (a/(a+b))/(c/(c+d))
Number needed to treat
1/ARR
60-70% of pts with myathinia gravis also have what?
10-15% of MG patients have what?
60-70 –> hyperplastic thymic tissue
10-15 –> thymoma
Pt in DKA, what are Na, K and Glucose levels in serum (early on before treatment)
Na –> LOW due to the osmotic activity of glucose (serum Na drops 1.6 for every 100 mg/dl rise in glucose)
K –> HIGH due to acid driving K/H exchange and because insulin driving K into cells is absent (total K body stores are actually depleted and will need to be replaced but appear high at first)
Glucose –> HIGH
Bilateral thombi in the lateral ventricles of a premature newborn seen on autopsy is caused by what?
This is due to interventricular hemorrhage, also known as germinal matrix hemorrhage (dense cellular and vascular layer of subependymal zone of the brain from which neurons develop) This should involute at 28 weeks gestation. This is a weak area of the brain and lacks structural support, which makes it vulnerable to spontaneous hemorrhage.
Can cause altered mental status and eventual death
Misoprostol vs Metoclopramide
Misoprostol –> PGE 1 analog that prevents NSAID induced peptic ulcers (and also maintenance of PDA)
Metoclopramide –> D2 receptor antagonist used as an antiemetic, and to treat gastroperesis
Nitrates effect on end diastolic LV volume and HR
Decrease EDLVV by direct vascular smooth muscle relaxation, which causes systemic venodilation
This causes a drop in BP that results in a REFLEX TACHYCARDIA
Allelic Heterogeneity
different mutations in the same gene locus cause similar phenotypes (more than one type of mutation is possible in a given gene)
3 children can all have Beta-Thalassemia with 3 different mutations caused the disease
Hemochromatosis
AR disease caused by excessive GI Iron absorption. Affected individuals store iron in the form of hemosiderin in the dermis and various parenchymal organs
Usually only presents after age 40 when significant amounts of iron have accumulated
Skin pigmentation is often and called “bronze diabetes”
DM from pancreatic island destruction is also common
Steps of ELISA test
- known antigen is fixed to the surface of a well
- pt serum is added. If present, antigen specific antibodies bind the antigen and remain fixed to the well. Plate is then washed
- anti-human immunoglobulin antibody is added coupled to a substrate modifying enzyme. This binds the bound antibodies
- Finally, a substrate which is modified by the enzyme to elicit a color change is added
How do efflux pumps work in bacterial antibiotic resistance?
Most antibiotic efflux pumps are powered by moving protons against their concentration gradient out of the cell coupled with moving the antibiotic against its concentration gradient.
Can also occur via sodium gradients or ATP mediated pumps
