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* NBME-15 questions set #2-4
 #726751  
  ppkyaw - 03/24/13 01:05
 
  1) A 72-year-old woman is admitted to the hospital because of an acute myocardial infarction. She undergoes cardiac catheterization. Angiography shows a left dominant circulation, and 90% narrowing of the artery supplying the diaphragmatic surface and atrioventricular node of the heart. A balloon angioplasty is scheduled during which a stent will be inserted in the narrowed vessel. The catheter and the balloon must be passed through which of the following vessels (stated in order) to reach the narrowed vessel?

A) left coronary, circumflex, anterior interventricular (left anterior descending)
B) left coronary, circumflex, posterior interventricular (posterior descending)
C) left coronary, posterior interventricular (posterior descending), circumflex
D) Right coronary, circumflex, anterior interventricular (left interior descending)
E) Right coronary, circumflex, posterior interventricular (posterior descending)
F) Right conronary, posterior interventricular (posteriro descending), circumflex

-----------------------------
2)Influenza virus strains are characterized by differing sensitivity to growth inhibition by the weak base ammonium chloride (AC). Influenza A San Francisco (SF) produces virus yields in AC-treated cells that approximate those in untreated cells, whereas influenza A New York (NY) grows poorly in AC-treated cells. To identify viral genes that segregate with differences in the sensitivity of these strains to AC, reassortant viruses are isolated by coinfecting cells with both virus strains. The ratios of the growth of the reassortant viruses in the presence and absence of AC are show in the table.

Virus Strain AC+/AC-Ration Genome Segment (protein)
Parental
NY 0.005 (PA)NY (HA)NY (NP)NY (NA)NY (M1/M2)
SF 0.8 SF SF SF SF SF
Reassortant
NY-SF/1 1.0 SF SF NY NY SF
NY-SF/2 0.8 NY SF NY SF SF
NY-SF/3 0.8 SF SF NY SF NY
NY-SF/4 0.5 NY SF SF NY NY
NY-SF/5 0.4 NY SF SF SF NY
NY-SF/6 0.008 NY NY NY SF SF
NY-SF/7 0.004 SF NY NY SF SF
NY-SF/8 0.002 SF NY NY SF NY

which of the following viral gene segments segregates with progeny viruses that are resistant to ammonium chloride?
A) HA
B) M1/M2
C) NA
D) NP
E) PA

------------------------
3) A 3-year-old girl is brought to the physician because of intermittent abdominal pain, constipation, and irritability fro 1 month. She lives with her family in a 50-year-old house that is currently being renovated. Physical examination shows pallor. Laboratory studies show a normocytic, hypochromic anemia and an increased plasma concentration of 5-amiolevulinic acid (Delta-ALA). Her blood lead concentration is 50 microg/dL (N
 
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* Re:NBME-15 questions set #2-4
#2858676
  yuyu2013 - 03/24/13 03:36
 
  1 B sure
2 A time is out so i can't answer,
ur copy ,NY-SF/3 0.8 SF SF NY SF NY , third one is SF , like that NY-SF/3 0.8 SF SF SF SF NY
 
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* Re:NBME-15 questions set #2-4
#2858733
  samyusmle - 03/24/13 09:58
 
  B
A
 
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* Re:NBME-15 questions set #2-4
#2859012
  dr_mle - 03/24/13 14:21
 
  can someone explain ans for 2??  
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* Re:NBME-15 questions set #2-4
#2863253
  dryousuf - 03/30/13 15:54
 
  please explain the answer for the 2 question!!!  
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* Re:NBME-15 questions set #2-4
#2864759
  totaa - 04/02/13 01:03
 
  did anyone can answer the second question please  
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* Re:NBME-15 questions set #2-4
#2869969
  dryousuf - 04/09/13 20:46
 
  any explanations for the 2 question?  
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* Re:NBME-15 questions set #2-4
#2870116
  kav17 - 04/10/13 04:36
 
  can any1 xplain the last que  
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* Re:NBME-15 questions set #2-4
#2884841
  princexjeo - 05/11/13 21:50
 
  If you look at the Parental strain of SF vs HA, SF has an AC+/- ratio of 0.8. HA is useless as its ratio is 0.005. Therefore in the progeny strains look for the Protein expressing the highest levels of SF = (HA). Why? (HA) expresses five out of seven re assortments for SF all between 0.4 and 1.0 therefore highest resistance  
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* Re:NBME-15 questions set #2-4
#2995806
  heresprerna - 10/31/13 01:06
 
  please explain the second ques again!!! thanx!!  
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