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* NBME 12 Q's...need help
  img87 - 02/07/12 18:32
  Can you please explain the answers..thanks (B is wrong!)
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* Re:NBME 12 Q's...need help
  img87 - 02/07/12 18:45

The Right ventricle has a higher coronary blood flow during "SYSTOLE"

Source 1 :

Coronary blood flow is unique in that there is interruption of flow during systole (mechnical compression of vessels by myocardial contraction. Coronary blood flow occurs predominatly during diastole when cardiac muscle relaxes and no longer obstructs blood flow through ventricular vessels. Conversely, right coronary arterial flow rate is highest during systole, because th aortic pressure driving flow increases more during systole (from 80 to 120mmHg) that the right ventricular pressure which opposes flow (from 0 to 25mmHg)

Source 2:

During systole, especially on the left side of the heart, the pressure within the coronary artery secondary to extravascular compression from the squeezing effect of the contracting myocardium virtually eliminates antegrade coronary blood flow. This situation is diagrammed in Figure 1623, in which the coronary blood flow goes to zero just prior to ventricular ejection, corresponding to isovolumic contraction and increased extravascular compression. 104 Conversely, coronary blood flow through the left side is maximal during early diastole, corresponding to the period of isovolumic relaxation (see Fig. 168, E to A) and minimal extravascular compression. Coronary blood flow through the right side, however, is maximal during peak systole, because developed pressure and consequently extravascular compression within the RV are considerably less than in the LV, thus allowing for antegrade flow during both systole and diastole

Here is the Graph
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* Re:NBME 12 Q's...need help
  img87 - 02/07/12 18:55
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* Re:NBME 12 Q's...need help
  img87 - 02/07/12 19:27
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* Re:NBME 12 Q's...need help
  eduardo - 02/07/12 20:06
  hey good idea on putting the questions up like this. im going to work on some this evening and post later  
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* Re:NBME 12 Q's...need help
  img87 - 02/08/12 11:37
  anyone who took NBME 12? A good review dudes and dames.  
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* Re:NBME 12 Q's...need help
  eduardo - 02/08/12 12:26
  sorry havent had a chance to look at these been busy with my schedule will try today img87  
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* Re:NBME 12 Q's...need help
  maryam2009 - 02/08/12 12:37

The most common changes in dennervation are atrophic fibres and fibre groups....
Reinnervation takes place in the chronic neuropathies......type grouping is a feature of reinnervation ....

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* Re:NBME 12 Q's...need help
  surela - 02/08/12 12:53

it is said that one congenital anomaly need to be it is neural tube defect

formula is..1/ecent rate in control-event rate in treatmen

so, 1/29%-0%=344
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* Re:NBME 12 Q's...need help
  img87 - 02/08/12 12:57
  @ surela...344 is wrong.. i picked that...ans key says F..not sure how thats calculated  
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* Re:NBME 12 Q's...need help
  surela - 02/08/12 13:00

ans is A

luprolide activates the gnrh in cantinious fashion and causes decrease androgen release.prostte carcinoma is androgen sensetive.
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