anudoc

10+ Year Member
Mar 22, 2008
36
0
Status
Academic Administration
1) The clearance of several substances wass measured at a constant GFR and constant urine flow rate, but at increasing plasma concentrations of substance. Under these conditions, clearance will increase at high plasma concentration for which of following substances?
a creatinine
b mannitol
c penicillin
d phosphate
e urea

2)Primary function of lysosomes in steroid producing cells?
a digest cellular debris
b hydrolyse spent cellular organelles
c remove steroid precursors
d cleave the ester from cholestrol ester to produce free cholestrol

3)Part of the oral cavity which is directly attached to periosteum?

4)What bacteria are found in sub gingival calculus?

5) In which form fluoride is absorbed in intestine?

6) What is the site of RNA synthesis?

7) Patient with Hepatitis B would show?
a HBsAg
b HBsAg antibodies

8) Retro virus causes what in infant?

9)High intensity disinfectant ? Kill Hep B, TB ,all spores

10) What is the cause of oral mucosa cyanosis?
 

simkarl

10+ Year Member
Sep 25, 2007
47
0
Status
Dentist
1) The clearance of several substances wass measured at a constant GFR and constant urine flow rate, but at increasing plasma concentrations of substance. Under these conditions, clearance will increase at high plasma concentration for which of following substances?
a creatinine
b mannitol
c penicillin
d phosphate -not sure
e urea .

2)Primary function of lysosomes in steroid producing cells?
a digest cellular debris
b hydrolyse spent cellular organelles
c remove steroid precursors
d cleave the ester from cholestrol ester to produce free cholestrol

3)Part of the oral cavity which is directly attached to periosteum?
I think attached gingiva

4)What bacteria are found in sub gingival calculus?

5) In which form fluoride is absorbed in intestine?

6) What is the site of RNA synthesis?
nucleus.

7) Patient with Hepatitis B would show?
a HBsAg
b HBsAg antibodies
depend on which stage first appears HBsAg during window anti- HBc when immunized anti-HBs

8) Retro virus causes what in infant?

9)High intensity disinfectant ? Kill Hep B, TB ,all spores
what do you mean high intensity disinfectant?

10) What is the cause of oral mucosa cyanosis?
please correct me. thanks
 

I'mFillingFine

Pulptastic
10+ Year Member
5+ Year Member
Jul 23, 2005
3,530
4
Shuffled off....
Status
Dental Student
I believe 1 is creatinine. Aren't inulin and creatinine the two best substances for measuring GFR?

Also, I think cyanosis of any peripheral region is caused by vasoconstriction or reduced cardiac output. (I don't think the oral mucosa is any different from other peripheral epithelium in that regard.)
 

skabbaraju

Unbound Imagination
10+ Year Member
7+ Year Member
Mar 30, 2007
470
1
TX
Status
Dentist
I believe 1 is creatinine. Aren't inulin and creatinine the two best substances for measuring GFR?

Also, I think cyanosis of any peripheral region is caused by vasoconstriction or reduced cardiac output. (I don't think the oral mucosa is any different from other peripheral epithelium in that regard.)
Thats correct!

Anudoc, can u please post your questions in NBDE Part I ,version 1.0 thread, created by shuntyman. Thank you.
 

simkarl

10+ Year Member
Sep 25, 2007
47
0
Status
Dentist
I believe 1 is creatinine. Aren't inulin and creatinine the two best substances for measuring GFR?

Also, I think cyanosis of any peripheral region is caused by vasoconstriction or reduced cardiac output. (I don't think the oral mucosa is any different from other peripheral epithelium in that regard.)
regarding question 1- you are right that creatinine and inuling are for measuring GFR but I understand they ask about substance that when increase concentration in plasma will increase clearence so freely filtered and high excreted in the same time ....inulin and creatinine freely filtered but no secretion or reabsorption happened..

please correct me ..
 

I'mFillingFine

Pulptastic
10+ Year Member
5+ Year Member
Jul 23, 2005
3,530
4
Shuffled off....
Status
Dental Student
regarding question 1- you are right that creatinine and inuling are for measuring GFR but I understand they ask about substance that when increase concentration in plasma will increase clearence so freely filtered and high excreted in the same time ....inulin and creatinine freely filtered but no excretion or reabsorption happened..

please correct me ..
I think it's somewhat of a trick question, making sure you know which substances are used to measure GFR. It's basically saying, "if there is more blood, what will there be more of?" instead of saying, "What's commonly filtered from the blood?" Since they don't mention anything that would relate to either secretion or reabsorption (which would mean it could NOT be creatinine or inulin), then we would know they were asking about another substance.

Hope that makes sense! Like if they asked something like, "If the kidneys were suddenly not able to reabsorb anything in the filtrate, what would rise?" then you'd look for an answer like glucose. I think they're just being tricky here.

Anyone else with input on this? We may be reading too much into it :)
 

impaction

10+ Year Member
Mar 26, 2008
207
0
Status
Dental Student
I think it's somewhat of a trick question, making sure you know which substances are used to measure GFR. It's basically saying, "if there is more blood, what will there be more of?" instead of saying, "What's commonly filtered from the blood?" Since they don't mention anything that would relate to either secretion or reabsorption (which would mean it could NOT be creatinine or inulin), then we would know they were asking about another substance.

Hope that makes sense! Like if they asked something like, "If the kidneys were suddenly not able to reabsorb anything in the filtrate, what would rise?" then you'd look for an answer like glucose. I think they're just being tricky here.

Anyone else with input on this? We may be reading too much into it :)
as inulin and creatinine are freely filtered,
this means that the will be removed from the blood
or whole of them will be removed from the blood
it can either by secreation or filtration
so by increasing directly their concentration in blood, their concentration in urine will increase proportionally

there is no compound whose excretion in urine is more than its concentration in blood
because its not possible
so none other compound fits into the category
hence answer is creatinine
 

simkarl

10+ Year Member
Sep 25, 2007
47
0
Status
Dentist
as inulin and creatinine are freely filtered,
this means that the will be removed from the blood
or whole of them will be removed from the blood
it can either by secreation or filtration
so by increasing directly their concentration in blood, their concentration in urine will increase proportionally

there is no compound whose excretion in urine is more than its concentration in blood
because its not possible
so none other compound fits into the category
hence answer is creatinine
if what you say is correct how can measure GFR by these substances..???
I know that now secreation for these substances..
thanks
 

impaction

10+ Year Member
Mar 26, 2008
207
0
Status
Dental Student
now here comes the concept
if the substance is freely filtered, and it cannot be secreted or absorbed then it is used to calculate GFR
but if the substance is cleared from urine either by....
filtration alone
or secretion alone
or both
but there is no reabsorption, then it is used for measuring clearance
and moreover the substance that is freely filtered COMPLETELY out of blood & can neither be secreted nor absorbed can be used for both GFR & clearance
whereas the substance used exclusively for clearance may or may not be ideal to measure GFR
 

impaction

10+ Year Member
Mar 26, 2008
207
0
Status
Dental Student
i will ask you a question that will help u understanding it.........
Q. pick the best option
a substance used to measure clearnace, is used to calculate what
1. GFR
2. renal plasma flow
this question is given in solved papers, & the answer given yhere is RPF
 

simkarl

10+ Year Member
Sep 25, 2007
47
0
Status
Dentist
i will ask you a question that will help u understanding it.........
Q. pick the best option
a substance used to measure clearnace, is used to calculate what
1. GFR
2. renal plasma flow
this question is given in solved papers, & the answer given yhere is RPF

ok impaction thanks for explanation...