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Renaissance Man

Renaissance Man

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So in April of 2014, the USMLE website released a "new" set of practice questions. There are 3 blocks of 46 questions, that you can find here. Before anyone asks, yes this is the same exact set of questions that you get if you pay to go to Prometric and take a practice run. The only difference I found is 3 or 4 audio/visual questions.

Anyways, since the material is freely available, I figured that we could discuss any of the questions that people are having trouble with...I will start:

"23. A 17 year-old boy comes to the emergency department because of severe thirst and weakness and 4-kg weight loss over the past 36 hours. He began having voluminous painless watery diarrhea on the airplane while returning from a trip to Thailand 36 hours ago. He has not vomited. While supine, pulse is 110/min and blood pressure is 110/60 mmHg. While standing, pulse is 170/min and blood pressure is 70/40 mmHG. His abdomen is contender and bowel sounds are increased. Which of the following treatments is most appropriate at this time?

(A) Ciprofloxacin
(B) Doxycycline
(C) Exploratory Lapartomay
(D) Potassium Chloride
(E) Rehydration
(F) Trimethoprim-Sulfamethoxazole"

I chose (E) as I figured with his orthostatic hypotension he is extremely dehydrated but the answer is (F). Am I missing something crucial here? Thanks!
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Answer is E. On my version of the PDF that is question 93 and it has the answer as E. I think this question has been on numerous other "free 150's" and I think the answer was E there too.
 
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I did all the questions, thank for the link, i got 35-6/46 right answers each block, is it bad or good?
 
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I have a few

upload_2014-6-6_9-58-4.png

What is going on here? The CO diffusing capacity makes C an obvious choice, but what is "Maximum voluntary ventilation?" Is it the ventilation rate it's referring to? Or actual entry of air into alveoli?

106. A healthy 28-year-old woman comes to
the physician for advice on losing weight.
She is 150 cm (4 ft 11 in) tall and weighs
56 kg (124 lb); BMI is 25 kg/m2. Physical
examination shows no other
abnormalities. The physician recommends
a diet that will restrict her daily intake by
500 kilocalories. Which of the following
processes is most likely to increase in this
patient as a result of following this diet?
(A) Adipocyte glucose uptake
(B) Cerebral ketone utilization
(C) Hepatic lipid oxidation
(D) Muscle glucose uptake
(E) Resting energy expenditure

Why is it not B?

113. A 30-year-old woman, gravida 3, para 3,
comes to the physician because of a 2-
month history of loss of urine when she
sneezes or laughs. Her three children were
all delivered vaginally at term. Physical
examination shows no abnormalities.
Which of the following nerve roots
supplies the muscle group that is
weakened in this patient?
(A) C1-2
(B) L1-2
(C) L4-5
(D) S1-2
(E) S3-4

What is the structure and nerve being referred to in the question? I can think of pelvic floor or urethral sphincters but that's as far as my pelvic anatomy knowledge goes.

122. An investigator is conducting a study of
hypertension in an experimental animal
model. Results show that hypertension is
induced when one renal artery is
constricted with a clamp, but both kidneys
remain intact. Which of the following best
explains the contribution of the normal
kidney to the hypertension in this
experimental model?
(A) Aldosterone-induced sodium and
water retention
(B) Angiotensin I-induced
vasoconstriction
(C) Angiotensin II-induced renal
vein constriction
(D) Expression of angiotensinconverting
enzyme
(E) Increased renin secretion

Why not E?
 
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tartrate said:
I have a few

View attachment 181953
What is going on here? The CO diffusing capacity makes C an obvious choice, but what is "Maximum voluntary ventilation?" Is it the ventilation rate it's referring to? Or actual entry of air into alveoli?

Tricky way of saying forced vital capacity. Since FVC decreased to a greater extent than FEV1 did, your FEV1/FVC ratio will be increased -- classic restrictive lung disease.

106. A healthy 28-year-old woman comes to
the physician for advice on losing weight.
She is 150 cm (4 ft 11 in) tall and weighs
56 kg (124 lb); BMI is 25 kg/m2. Physical
examination shows no other
abnormalities. The physician recommends
a diet that will restrict her daily intake by
500 kilocalories. Which of the following
processes is most likely to increase in this
patient as a result of following this diet?
(A) Adipocyte glucose uptake
(B) Cerebral ketone utilization
(C) Hepatic lipid oxidation
(D) Muscle glucose uptake
(E) Resting energy expenditure

Why is it not B?

Because you're still taking in calories. Your brain is only going to rely on ketones in a complete absence of glucose, which is not the case here. People who go on ketogenic diets can eat NO carbs, because even a little bit of glucose in your blood will prevent your brain from utilizing ketones.


122. An investigator is conducting a study of
hypertension in an experimental animal
model. Results show that hypertension is
induced when one renal artery is
constricted with a clamp, but both kidneys
remain intact. Which of the following best
explains the contribution of the normal
kidney to the hypertension in this
experimental model?
(A) Aldosterone-induced sodium and
water retention
(B) Angiotensin I-induced
vasoconstriction
(C) Angiotensin II-induced renal
vein constriction
(D) Expression of angiotensinconverting
enzyme
(E) Increased renin secretion

Why not E?

Because it's asking about the NORMAL kidney. Why would the normal kidney be making more Renin? It wouldn't. The clamped kidney will release more renin because it's flow is reduced. This will in turn activate angiotensin I, then angiotensin II, which will lead to increased aldosterone release. The aldosterone is going to work at BOTH kidneys to retain more sodium, and water will follow.
Click to expand...

Answers in bold.
 
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Why is C5a the answer?! What the f*** is this??
 

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conan31 said:
Why A is the answer? I really don't know :doctor:
Click to expand...
A is basically showing you that all three vesicles would have the same genetic material. If you get a herpes outbreak its most likely originates from a single virus that is replicating rather than multiple viruses with different genetic material all erupting at the same time.
 
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conan31 said:
Why A is the answer? I really don't know :doctor:
Click to expand...

Because he has herpes. The question is saying they sampled virus from multiple lesions and then ran their DNA on a gel. It's the exact same virus so their DNA should be exactly the same
 
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conan31 said:
Why is C5a the answer?! What the f*** is this??
Click to expand...

I'm not exactly sure, but I think that cell is an eosinophil? Anyways, I answered C5a for this question because it is a potent pro-inflammatory acute phase protein, and also a chemoattractant for granulocytes.
 
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Are the answers for the free 150 provided at the end of the online (like if I downloaded the software) version, or only via the PDF?
 
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The answers are provided selecting 'show answer option' before loading of blocks.

About C5a: maybe, the cell is detached from the others, and so it needed C5a that is perforating to be detached.... haven't C5a the make pores power?

About HSV1 question: I really didn't know that 1,2,3 standed for 3 cells infected by virus, it is not written, you are smarter than me!
 
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If you do the Free 150 at a prometric center, make sure they're the "new" ones. If not, I'd advise doing the new ones on your own. Mine ended up being the older ones.
 
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orchitisphlebitis said:
If you do the Free 150 at a prometric center, make sure they're the "new" ones. If not, I'd advise doing the new ones on your own. Mine ended up being the older ones.
Click to expand...

Wait what?
The new one is on their website for free and they gave you an old one in the testing center? wtfff
 
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J DUB said:
Are these questions kinda easy compared to the real thing? I have been told they are and they seem to be fairly easy.
Click to expand...

thought it was a good representation of what Step 1 looked like. A mix of easy, kinda difficult and a few wtfs.
 
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Are there score correlations for this test? / what are most people scoring relative to their nbmes?
 
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conan31 said:
Why is C5a the answer?! What the f*** is this??
Click to expand...
The arrow is pointing to a neutrophil. C5A is an anaphylatoxin that serves as a inducer of chemotaxis of acute inflammatory cells (i.e. neutrophils to the area).
 
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Enzymes said:
Are there score correlations for this test? / what are most people scoring relative to their nbmes?
Click to expand...
I am wondering the same thing! My test itself isn't until the end of this week, so I can't really speak to if/how my Free 150 score correlated with my real score, but for what it's worth, my last 3 NBME have been (NBME 12) 231, (11) 237, (16) 243 - and I got an 87% on the Free 150 today. how about you?
 
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sjonies88 said:
I am wondering the same thing! My test itself isn't until the end of this week, so I can't really speak to if/how my Free 150 score correlated with my real score, but for what it's worth, my last 3 NBME have been (NBME 12) 231, (11) 237, (16) 243 - and I got an 87% on the Free 150 today. how about you?
Click to expand...

What is your UW % right now........
 
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I got an 85%...NBMEs are 243 average. I still have to take 16.

Also I had a question about one:

A study is designed to evaluate the feasibility of
acupuncture in children with chronic headaches.
Sixty children with chronic headaches are
recruited for the study. In addition to their usual
therapy, all children are treated with acupuncture
three times a week for 2 months. Which of the
following best describes this study design?

(A) Case-control
(B) Case series
(C) Crossover
(D) Cross-sectional
(E) Historical cohort
(F) Randomized clinical trial

Can someone explain why the answer is Case series? I always thought case series was more of documentation of what happens, rather than actually administering a new treatment. I admit that none of the other answers make sense, but can anyone explain what you are looking for in a case series? Thanks!

Also the swordfish question...wtf!
 
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Also can someone explain how to distinguish between hemothorax and hemopneumothorax?

A 16-year-old boy is admitted to the emergency
department because of a knife wound to the left
side of his chest. An x-ray of the chest shows an
air-fluid level in the left side of the chest, partial
collapse of the left lung, and elevation of the
stomach bubble. The mediastinum is in the
midline. Which of the following is the most
likely diagnosis?
(A) Hemopneumothorax, not under tension
(B) Hemothorax, not under tension
(C) Pneumothorax, not under tension
(D) Tension hemopneumothorax
(E) Tension hemothorax
(F) Tension pneumothorax
 
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Enzymes said:
Also can someone explain how to distinguish between hemothorax and hemopneumothorax?

A 16-year-old boy is admitted to the emergency
department because of a knife wound to the left
side of his chest. An x-ray of the chest shows an
air-fluid level in the left side of the chest, partial
collapse of the left lung, and elevation of the
stomach bubble. The mediastinum is in the
midline. Which of the following is the most
likely diagnosis?
(A) Hemopneumothorax, not under tension
(B) Hemothorax, not under tension
(C) Pneumothorax, not under tension
(D) Tension hemopneumothorax
(E) Tension hemothorax
(F) Tension pneumothorax
Click to expand...
Believe it has to do with the air-fluid level. If it was a hemothorax, you wouldn't see that. Someone can probably give a more comprehensive answer.
 
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sjonies88 said:
It was 71% on my first pass - random, timed blocks of 46. Why?
Click to expand...

Trying to get an idea of how your NBMEs relate to UW average. For example, is that 71% equal to a 240 kinda thing.

Why I wanted your most recent average to get a better idea. It is being discussed in another thread.
 
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J DUB said:
Trying to get an idea of how your NBMEs relate to UW average. For example, is that 71% equal to a 240 kinda thing.

Why I wanted your most recent average to get a better idea. It is being discussed in another thread.
Click to expand...

Nah 71 % does not automatically = 240 I think everyone is different and just really depends on the person.
I'm getting > 71 % on Uworld but significantly < 240 on NBMEs
 
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I know. I am just trying to get an idea. I found this website over on the other thread I reposted and it gave numbers like a 65% being a 240 and it does not look right to me.

So, I was trying to see if most could agree if a 65 is 230 and lows 70s is 240. But, there appears to be a fair amount of variability in there.
 
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J DUB said:
I know. I am just trying to get an idea. I found this website over on the other thread I reposted and it gave numbers like a 65% being a 240 and it does not look right to me.

So, I was trying to see if most could agree if a 65 is 230 and lows 70s is 240. But, there appears to be a fair amount of variability in there.
Click to expand...

I would say just to be safe > 70 % on Uworld is probably > 230 on NBME. On the real deal might be a different story.
 
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Enzymes said:
Also can someone explain how to distinguish between hemothorax and hemopneumothorax?

A 16-year-old boy is admitted to the emergency
department because of a knife wound to the left
side of his chest. An x-ray of the chest shows an
air-fluid level in the left side of the chest, partial
collapse of the left lung, and elevation of the
stomach bubble. The mediastinum is in the
midline. Which of the following is the most
likely diagnosis?
(A) Hemopneumothorax, not under tension
(B) Hemothorax, not under tension
(C) Pneumothorax, not under tension
(D) Tension hemopneumothorax
(E) Tension hemothorax
(F) Tension pneumothorax
Click to expand...


hemothorax -> blood in the pleural area, no collapse of lung. hemopneumothorax -> blood in the pleural area, collapsed lung.

this is basically a vocab question testing whether you can string together a bunch of latin pre/suffixes to describe what's going on in this patient.
 
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Actually, you sure notbob? I thought pneumothorax meant air in the pleural space. Wouldn't hemothorax also cause collapsed lungs since blood will increase pleural pressure and also cause the alveoli to collapse?
 
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Enzymes said:
Can someone explain why the answer is Case series? I always thought case series was more of documentation of what happens, rather than actually administering a new treatment. I admit that none of the other answers make sense, but can anyone explain what you are looking for in a case series? Thanks!
Click to expand...
This is a documentation of what happens (when you add acupuncture therapy to the treatment regime). When there is no set up for a scientific study/clinical trial (Grouping, randomisation, blinding, etc.) then all you have are cases.
 
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