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* NBME 5 Block 4__sarim, yeahbiruh, any1 please help
 #500191  
  iqbalian01 - 04/18/10 00:55
 
  Q12) so the most conclusive sign that ovulation has occurred is due to increase of progesterone and now the LH surge?

Q23) I’m confused on this question. Please explain.

Q33) how do you differentiate between cystitis & epididymitis? Wouldn’t both of them be potential complications in this case?

Q39) is the following labeling correct??
A-macrophages
B-capillaries
C-type II cells (lamellar bodies)
D-type I cells

Q46) I’m a little confused if it’s 1.5 or 2L? please explain.

thanks.
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082779
  yeabiruh - 04/18/10 13:39
 
  q 12...here is the order how ovulation occurs.
1-estrogen level rise above certain level,they no longer inhibit the release of LH and FSH .Instead they stimulate the release of LH and FSH (negative feedback loop to positive feedback loop )
2-This causes surge in the release of LH and FSH .Only the LH isurge is essential for the induction of ovulation and the formation of corpus luteum.Therfore if estrogens are still rising ovulation hasnot occured.
3-Graffian follicular rupture occurs 24-36 hours after the onset of the LH surge .
4-Luteal phase starts .And the metabolic pathways are then altered in the granulosa and thecal cells in favor of progesterone production.

5-luteal cells (transformed granulosa and thecal cells ) start to produce considerable progesterone and some estrogen.....

so in my thinking it is Progesterone level in the serum that shows ovulation has occurred ....


EEEE
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082801
  yeabiruh - 04/18/10 14:01
 
  q 23-on the Y axis...minute ventilation ( Minute Ventilation =TIDAL VOLUME x BREATHS/MIN)
on the X axis inspired oxygen concentration

Factors affecting minute ventlation are depth of breathing and Rate of breathing as we can see in the formula.And the ones which regulate these factors (depth and rate of breathing ) are Central Chemoreceptors and Peripheral Chemoreceptors.
Central chemoreceptors (MEDULLA )directly monitor and and are stimulated by CSF H+ and CO2....Whereas Peripheral Chemoreceptors (Carotid bodies and Aortic Bodies..the carotid one is the most important ) respond to both PO2 and H+/CO2 ...but mainly respond to low level of oxygen in the blood....PO2 < 60 MMHG

Hence in this graph we are looking for the response of Carotid Bodies in respone to The level of Oxygen...The way to read the graph is from right to left (which means from high inspired oxygen concentration to low oxygen concentration ...as WE go from right to left on the normal graph we see an increase(which was constant ) in minute ventilation because of a decrease in PO2 < 60 mmhg (this response is mediated by carotid bodies)...

So in the experimental animal we removed the carotid bodies and there is no response (increase ) in minute ventilation if there is a decrease in the PO2 ...which is DDDD

The key is to read the graph from right to left on the x axis (not the usual left to right )

This is my thinking ...I might be wrong .....
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082812
  yeabiruh - 04/18/10 14:11
 
  q 33--this is gonococcal urethritis and the complications of gonococcal urethritis are mainly to reproductive organs ...like epidydimis,prostate ...If it had been Ecoli urethritis more of urinary organs get the complication ...hence i think epidydimitis is the better choice as the complication of gonococcal urethritis....

 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082846
  yeabiruh - 04/18/10 14:39
 
  q46-the question asks the value of Functional Residual Capacity...(volume of gas in the lungs at the end of passive expiartion ,the neutral point for the respiratory system....At FRC the forces on the chest wall and lung are in equilibrum(that means the pressure on both systems cancels out at FRC) ...
so let us try the pressures on the chest wall and lung at the given volumes in the choice
A-Volume 0.5 ....Pressure on the chest wall -20 ,pressure in the lung + 5...not canceled out
B-Volume 1 .......Pressure on the chest wall -17 ,pressure in the lung +7...not canceled out
C-volume 1.5....pressure on the chest wall - 14,pressure in the lung + 8...not canceled out
D-Volume 2......pressure on the cheast wall -10 ,pressure in the lung + 10..canceled out
E-Volume 2.5..pressure on the chest wall -5 ,pressure in the lung +13,not canceled out
Hence the answer in my thinking is DDDD as it the volume of the gas in the liungs where the forces are at equilibrum (FRC )......
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082970
  iqbalian01 - 04/18/10 16:44
 
  great! thanks a whole bunch yeabiruh!!!! :)

is my labeling for question 39 correct?
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2082972
  iqbalian01 - 04/18/10 16:46
 
  and i agree with you on your answers...the explanation for questions 23 & 46 was super helpful!  
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2083027
  yeabiruh - 04/18/10 18:01
 
  Q 39 i agree with ur labeling ....here is the link

http://webanatomy.net/histology/respiratory/alveoli.jpg

TYPE II is more of foamy in appearance whereas Type I is more of spindle shaped as u labeled it....Macrophages can also be found in the alveolar space (as well as in the alveolocapillary membrane ) ...I think that is why there are two arrows for macrophages (one pointing the wall and the other the alveolar space )unlike the other labelings(pointing only to the wall ).......so the answer could be CCCCCC


Thanks
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2083030
  yeabiruh - 04/18/10 18:05
 
  for q 39 here is also another link....
http://legacy.owensboro.kctcs.edu/gcaplan/anat2/notes/A83_Alveoli_TypeI...&II_40X.jpg
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2083040
  iqbalian01 - 04/18/10 18:20
 
  awesome slides. i tried searching for them, but couldnt find any like the ones you did.
hope your prep is going extremely well and you do great on your exams!!!
thanks a zillion! :)
 
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* Re:NBME 5 Block 4__sarim, yeahbiruh, any1 please h
#2083057
  yeabiruh - 04/18/10 18:35
 
  THANKS ...THE SAME TO UUUUUUUUUUU...i wish uuuuu big 9999999  
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