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Welcome to zpatel's page.
Contributor score: 15

Comments ...

smpate  Nice find, thanks!

 +0  (nbme22#44)

Can anyone tell the effect of aspirin on a blood lab value (i.e PT,PTT,Fibrin product)?

paperbackwriter  Aspirin only increases platelet aggregation (blocks COX1/2 --> decreased production of Thromboxane A2 --> decreased aggregation). That's why it only increases bleeding time and has no effect on PT, PTT, and fibrin products. PT and PTT are only affected if something messes the coagulation cascade.

 +0  (nbme23#32)

all the others a noncompetitive since they have specificity(specific ligands), NMDA is the only nonselective(hence competitive receptor), has a ligand site and ca , na and mg...hence competitive

hello  the question says competitive interactions, i think this is different from competitive binding.

Subcomments ...

Malonyl-CoA inhibits the rate-limiting step in the beta-oxidation of fatty acid. Logically, resting muscle requires less energy (and thus less need for fatty acid breakdown) than active muscle.

zpatel  it inhibits Carnitine acyltransferase-1 in beta-oxidation. +3  
melchior  FA 2020 pg 89 +  

The effects of excess thyroid hormone: attempted compensatory TSH suppression, increase in both T4 and free T4, and normal TBG. Note that the question doesn’t even hinge on TBG and is also unlikely to on the real thing.

d_holles  When do we care about TBG? +  
zpatel  @d_holles in pregnancy. +  

Electrical alternans on boards means a big pericardial effusion (and usually cardiac tamponade physiology). The heart cannot fill properly, preload decreases, hypotension and tachycardia ensue, fluid backup leads to elevated JVP. Underlying etiology in this patient is renal failure.

zpatel  Cardiac temponade. +  
melchior  Hypotension and jugular venous distension are two components of Beck's triad, which is associated with acute cardiac tamponade. The third component is muffled heart sounds, which is not addressed in this question. +1  

submitted by haliburton(173),

there are two essential fatty acids: linoleic = omega 6, and alpha-linoleic = omega 3.

lizard  Found in fish oils and are shown to lower triglyceride levels. +1  
zpatel  alpha-Linolenic ==> omaga 3 +3  

The clues for trichotillomania were the death of her grandmother suddenly, since trichotillomania is often stress-induced. I also narrowed it down by it saying the hair was in different growth stages in the patchy areas, which makes sense if she’s plucking them out at different times.

Telogen effluvium is most common in middle-aged women, so she doesn’t fit the profile (but you’re right about it being caused by stress).

zpatel  What about telogen effluvium? psychological stress-related hair loss. +  
elephantbuddy  Just to add on, telogen effluvium is usually due to physical stressors such as surgery, pregnancy, serious illnesses, or severe/life-threatening psychological stress. So although this patient is going through psychological stress, it's not exactly life-threatening enough to result in hair loss unless personally inflicted. I think the question stem also kind of hints at trichotillomania with her doing more things to her hair. But this article is pretty useful in distinguishing between different causes of hair loss: https://www.aafp.org/afp/2003/0701/p93.html#sec-4 +  

submitted by nwinkelmann(218),

Here's a GREAT video explaining ultrasound findings of pregnancy. @9:57 is a great picture so far with labels of the yolk sac, gestational sack, fetal pole, and amnion. One thing the person explaining said that I thought would be good to keep in mind is that the yolk sac looks like a cheerio inside the gestational sac. Also, this site has a bunch of pictures as well: https://radiopaedia.org/articles/first-trimester?lang=us.

zpatel  what video? +7  
usmlecharserssss  porn video how they make this embryo and yolk sac +  
samsam3711  Shorter video that explains this pretty well: https://www.youtube.com/watch?v=01mMBDEthV8 +1  
focus  @samsam3711 that video is BOMB. Thank you!!! +  

submitted by welpdedelp(154),

2/3 1/25 1/4

He has a 2/3 chance of being heterozygous (not 2/4 b/c we know he for sure doesn't have CF)

1/25 chance in the population

1/4 chance of a heterozygous couple having a child with CF

welpdedelp  ok, so it messed up the formatting 0.66667 x 1/25 x 0.25 +  
nwinkelmann  ugh... I ALWAYS forget about changing the carrier status to 2/3. Chance of affected individual = chance of father passing allele * chance of mother passing allele = 2/31/21/25*1/2 = 2/300 = 1/150. +  
zpatel  2/3(chance of heterozygous) * 1/25(meet carrier) * 1/2(chance of male to transfer affected gen) * 1/2(female to transfer affected gen) = 1/150 +1  

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