NBME 7 question - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     64,953 Members     275,038 Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 40
Threads: 22
Thanked 2 Times in 2 Posts
Reputation: 12
Default NBME 7 question

A pharmacologist discovers a new fungal metabolite with unusual antimicrobial properties. It naturally concentrates in the endosomes, lysosomes, and phagolysosomes of cells and directly kills microorganisms (eg, Mycobacterium tuberculosis) that are normally resistant to degradation in the phagolysosomes. The metabolite has the undesirable effect of increasing the pH within phagolysosomes. Which of the following processes will be primarily affected?

A)Class I MHC molecule peptide loading

B)Class II MHC molecule peptide loading

C)Peptide binding to T-lymphocyte receptor αβ

D) Peptide binding to T-lymphocyte receptor γδ

What is the answer and why? FYI ppl reading this...I'm going to post like 30 questions online today These are the questions that I simply do not understand. I would really appreciate your help. I need a 15 point increase by the end of the month. Hopefully this helps everyone.
Reply With Quote Quick reply to this message



  #2  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: 1 + CK
Posts: 40
Threads: 4
Thanked 22 Times in 14 Posts
Reputation: 32
Default The answer is B

MHC II
Expressed only on antigen-presenting cells (APCs).
Antigen is loaded following release of invariant chain in an acidified endosome
Reply With Quote Quick reply to this message
  #3  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 40
Threads: 22
Thanked 2 Times in 2 Posts
Reputation: 12
Default Explanation please

A 7 yr old boy drinks cocoa and watches TV while petting his cat. He watches while his mother bakes fragrant cinnamon rolls while the stereo plays Mozart's string quartet in the background. Which of the following sensory modalities goes directly to the cortex without going into the thalamus.

1. Hearing
2 Taste
3. Touch
4. Vision
5. Smell
Reply With Quote Quick reply to this message
  #4  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 40
Threads: 22
Thanked 2 Times in 2 Posts
Reputation: 12
Default

During an experiment 500mg of both drug X and Y are simultaneously administered IV, the serum concentration of both drugs after bolus administration is 5 mg and 2.5mg respectively. Assuming no drug interactions. Which of the finding regarding the drug Y is compared with drug X?

A. decreased clearance
B. decreased half life
C. decreased volume of distribution
D. increased clearance
E. increased half life
F. increased volume of distribution

I googled and found out that the answer. BUT I don't understand it. Can someone please explain? Thanks
Reply With Quote Quick reply to this message
  #5  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 6
Thanked 4 Times in 3 Posts
Reputation: 14
Default It's b

increase in the pH interfere with the peptide protein (presented by the antigen presenting cells) binding to the MHC-II molecules which is expressed on the APCs
Reply With Quote Quick reply to this message
  #6  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 40
Threads: 22
Thanked 2 Times in 2 Posts
Reputation: 12
Default

25) a healthy 54 year old woman undergoes an exercise stress test. During the moderate phase of the exercise, her pulse is 140/min, respirations are 25/min, & bp is 130/90 mmHg. Which of the following is the relative proportion of coronary oxygen delivery during the rest & during the exercise times?

Rest moderate exercise
a) systolic > diastolic systolic > diastolic
b) systolic > diastolic systolic < dia
c) systolic < diastolic systolic > diastolic
d) sys < dia sys < dia
e) sys = dia sys > dia
f) sys = diastolic sys < dia

I thought that coronary arteries always fill during diastole...therefore oxygen delivery is highest during diastole. I'm obviously incorrect. Explanation please.
Reply With Quote Quick reply to this message
  #7  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 6
Thanked 4 Times in 3 Posts
Reputation: 14
Default Smell

Hearing-----> MGN (Medial geniculate nucleus) in the thalamus
Taste------> VPM (Ventral posteromedial n.)
Touch------> VPL (Ventral posterolateral n.)
Vision------> LGN (Lateral geniculate n.)
SMELL goes straight to the cortex without relaying in the thalamus
Reply With Quote Quick reply to this message
The above post was thanked by:
OMGStep (04-02-2013), probenss (08-11-2013)
  #8  
Old 04-02-2013
MedicalExaminer's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 763
Threads: 63
Thanked 414 Times in 271 Posts
Reputation: 424
Default

Quote:
Originally Posted by OMGStep View Post
During an experiment 500mg of both drug X and Y are simultaneously administered IV, the serum concentration of both drugs after bolus administration is 5 mg and 2.5mg respectively. Assuming no drug interactions. Which of the finding regarding the drug Y is compared with drug X?

A. decreased clearance
B. decreased half life
C. decreased volume of distribution
D. increased clearance
E. increased half life
F. increased volume of distribution

I googled and found out that the answer. BUT I don't understand it. Can someone please explain? Thanks
LD was 500mg
LD=CpxVd/F
F=1
Cp=LD/Vd

Larger volume of distribution contributed to decreased plasma concentration
__________________
Everything is possible for him who believes (MARK 9:23)
Reply With Quote Quick reply to this message
The above post was thanked by:
OMGStep (04-02-2013)
  #9  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 6
Thanked 4 Times in 3 Posts
Reputation: 14
Default

Volume of distribution = loading dose/plasma concentration
Vd (drug x)= 500/5=100
Vd (drug Y)=500/2.5)=200
So there is an increase of the Vd of drug Y
Reply With Quote Quick reply to this message
  #10  
Old 04-02-2013
USMLE Forums Scout
 
Steps History: Not yet
Posts: 16
Threads: 6
Thanked 4 Times in 3 Posts
Reputation: 14
Default 25-d

DD
coronaries fill more during diastole regardless of resting or excercising muscle
Reply With Quote Quick reply to this message
  #11  
Old 04-15-2014
USMLE Forums Scout
 
Steps History: Not yet
Posts: 64
Threads: 13
Thanked 1 Time in 1 Post
Reputation: 11
Default nbme 7

a 68 yr old woman with left homony hemianop for 2 wks, and to find the lesion on the c t...

its supposed to be on the right side, that i know. i put choice E, which seemed like the optic tract.
but it was wrong.

can anyone pls pls pls explain?????/
Reply With Quote Quick reply to this message
  #12  
Old 01-14-2015
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 2
Threads: 0
Thanked 0 Times in 0 Posts
Reputation: 10
Default

A 42-year-old man needs a kidney allograft .His lymphocytes are examined by the mized lymphocyte reaction with killed stimulator cells from himself and from each of 5 prospective donors. A donor with which of the following thymidine incorporation values (cpm) will be most compatible ? (the patient has a thymidine incorporation value of 425 /cpm)

A) 312
B) 1542
C) 2505
D) 15.389
E) 27.482
Reply With Quote Quick reply to this message
  #13  
Old 01-14-2015
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 2
Threads: 0
Thanked 0 Times in 0 Posts
Reputation: 10
Default

Quote:
Originally Posted by dr rookie View Post
a 68 yr old woman with left homony hemianop for 2 wks, and to find the lesion on the c t...

its supposed to be on the right side, that i know. i put choice E, which seemed like the optic tract.
but it was wrong.

can anyone pls pls pls explain?????/


it seems like your choice optic tract
Reply With Quote Quick reply to this message
  #14  
Old 03-04-2015
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 2
Threads: 0
Thanked 0 Times in 0 Posts
Reputation: 10
Default

Does anyone have the NBME 12 and 7 form offline pleaseeeee I need it
Thanks
Adri_c24@hotmail.com
Reply With Quote Quick reply to this message
  #15  
Old 3 Weeks Ago
USMLE Forums Scout
 
Steps History: Not yet
Posts: 19
Threads: 7
Thanked 3 Times in 3 Posts
Reputation: 13
Default NBME 7 behavioral science question

A 42-year-old woman comes to the physician for a follow-up examination after she received two increased blood pressure readings on different days. Her blood pressure now is
140192 mm Hg. Physical examination shows no other abnormalities. In addition to considering pharmacotherapy, the physician recommends a low-sodium diet Which of the following
initial statements is the most appropriate approach to educating this patient about decreasing her sodium intake?
o A) "The Internet is a great way to learn about methods to decrease sodium in your diet"
o B) "Do you know what kinds of foods are high in sodium?"
o C)" will send you a brochure outlining the low-sodium diet you will need to follow."
o D) ''You must see a nutritionist to discuss decreasing your sodium intake"
o E) ''You need to lower your intake to fewer than three grams of sodium daily"
Reply With Quote Quick reply to this message



  #16  
Old 3 Weeks Ago
USMLE Forums Scout
 
Steps History: Not yet
Posts: 19
Threads: 7
Thanked 3 Times in 3 Posts
Reputation: 13
Default

stuck between B or E. Which one you think?

Quote:
Originally Posted by PeterPan View Post
A 42-year-old woman comes to the physician for a follow-up examination after she received two increased blood pressure readings on different days. Her blood pressure now is
140192 mm Hg. Physical examination shows no other abnormalities. In addition to considering pharmacotherapy, the physician recommends a low-sodium diet Which of the following
initial statements is the most appropriate approach to educating this patient about decreasing her sodium intake?
o A) "The Internet is a great way to learn about methods to decrease sodium in your diet"
o B) "Do you know what kinds of foods are high in sodium?"
o C)" will send you a brochure outlining the low-sodium diet you will need to follow."
o D) ''You must see a nutritionist to discuss decreasing your sodium intake"
o E) ''You need to lower your intake to fewer than three grams of sodium daily"
Reply With Quote Quick reply to this message
  #17  
Old 3 Weeks Ago
USMLE Forums Newbie
 
Steps History: Not yet
Posts: 5
Threads: 1
Thanked 0 Times in 0 Posts
Reputation: 10
Default

Quote:
Originally Posted by ayvazoglutugba View Post
A 42-year-old man needs a kidney allograft .His lymphocytes are examined by the mized lymphocyte reaction with killed stimulator cells from himself and from each of 5 prospective donors. A donor with which of the following thymidine incorporation values (cpm) will be most compatible ? (the patient has a thymidine incorporation value of 425 /cpm)

A) 312
B) 1542
C) 2505
D) 15.389
E) 27.482
thymidine incorporatn values (TIV) is the indicator of immunogenicity,so greater value of TIV test of donor indicates unsatisfactory match btwn donor and recipient MHC class II,which will cause rejection of the graft.
This means the donor with least value of TIV will be the best donor
Reply With Quote Quick reply to this message



Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Nbme 11 question #1 DocSikorski USMLE Step 1 Forum 9 03-11-2014 12:10 PM
*NBME question warfarin90 USMLE Step 1 Forum 10 02-02-2014 08:09 PM
nbme question dianne1720 USMLE Step 2 CK Forum 0 09-20-2012 08:55 AM
NBME Question usmlepak USMLE Step 2 CK Forum 1 11-11-2011 02:06 PM
NBME 7 Question montre USMLE Step 1 Forum 0 09-15-2011 02:07 PM

RSS Feed
Find Us on Facebook

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)