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Discussion Starter · #41 ·
thanks and how do you differentiate between RRR relative reduction and absolute risk reduction i cant understand the explanation of these two given in FA 2014 and uworld ??
ARR shows us the difference between two absolute units (8% - 2% = 6%) or absolute difference between two relative units :eek:. Reduction - is decreasing by another words. Without vaccine - 8% are ill, with vaccine - 2%. So, we want to know, what is the purpose (the use) of vaccination. ARR answer us for this question. Vaccine decrease the incidence by 6% (ARR).

Relative risk (RR) - it is a relation (ratio) - 8%/2% or 2%/8% depends on purpose. So, incidence in unvaccinated group is 4 times more than in vaccinated or incidence in vaccinated group is 0,25 of incidence in unvaccinated. Now we get: FA-2014 - RRR= 1 - RR (1 - 0,25 = 0,75), and in wiki - RRR=ARR/incidence in control (without vaccine in this case).
RRR= 0,06/0,08 = 0,75.

May be this will be helpful.
 

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Discussion Starter · #42 ·
This question is not clear for me. I've answered C and got incorrect.
An 8-year-old girl is brought to the physician for a well-child examination. Her mother says that she has been well except for an occasional cold. Her immunizations are up to date. She is at the 50th percentile for height and 60th percentile for weight. Physical examination shows breast bud development and a few pubic hairs. The mother asks whether her daughter's development is normal. Which of the following is the most appropriate initial response by the physician?
A) "I am concerned that your daughter may have precocious puberty."
B) "I think that your daughter is likely to begin menstruating in the next few months."
C) "I would like to order laboratory studies to ensure that your daughter's development is normal."
D) “Your daughter's breast development is somewhat less than might be expected for her age."
E) “Your daughter's development is normal."

Here we see Tanner-2 (10-11,5 y.o.), hypothyroidism(?)
 

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For 1-2
Would everything decrease since smoke impairs mucociliary clearance?

http://www.ncbi.nlm.nih.gov/books/NBK53021/
" In addition, high-level exposures, particularly when sustained, may overwhelm the lung's defenses, and some agents have the potential to reduce the efficacy of these defenses. Cigarette smoke, for example, contains components that impair mucociliary clearance (Table 7.3)."

Hello everyone. I've made recently nbme 16. If anyone can help with answers and to participate in discussion, please, you're welcome.

1-2
An animal study is conducted to assess the effects of smoking on pulmonary defense and maintenance mechanisms. For 1 week, normal
male rats are exposed to levels of cigarette smoke comparable to those encountered by humans who smoke cigarettes. Results of
pulmonary testing are compared with baseline levels obtained the week before the smoke exposure. Which of the following sets of changes
is most likely to be observed?

Mucus Production and Secretion up/down

Alveolar Macrophage Function up/down

Activity of Airway Cilia up/down

1-4
Poliovirus mRNA lacks a 5' m7G cap but is translated efficiently by cellular ribosomes. Which of the following additional structural features of poliovirus mRNA is the most likely cause of its ability to be translated in the absence of a cap?
A) Absence of a 3' untranslated region (UTR)
B)Absence of a 5' UTR
C) Absence of a poly(A) tail
D) Presence of an internal ribosome entry site
E) Very short open reading frame

1-11
An 85-year-old woman is diagnosed with a fracture of the right femur and begins treatment with morphine by patient-controlled analgesic pump. Three days later, her respirations are 6/min. Physical examination shows pinpoint pupils. Her serum creatinine concentration is 1.8 mg/dL. Which of the following best explains this patient's clinical deterioration after the initiation of morphine therapy?
A) Chronic dosing of morphine decreases its bioavailability
B) Morphine bioavailability increases with chronic dosing
C) Morphine downregulates mu-opioid receptors with chronic dosing
D) Morphine inhibits its own metabolism
E) Morphine is metabolized to active metabolites that accumulate
 

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I chose the same answer. Some sources show tanner stage 2 for girls range from 8-15 yo, boys: 10-15 yo

I don't get this micro question.
26 month old boy with SOB & cough who had cutaneous abscesses caused by S. aureus. febrile, x-ray shows cavitary infiltrate of left lingula. Culture grows filamentous gram + rods. Answer choices are
A. Bacillus anthracis
B. Candida
C. Nocardia
D. Pneumocystis
E. Strep bovis

I think it's A but it's wrong. Any thoughts? Thanks.

This question is not clear for me. I've answered C and got incorrect.
An 8-year-old girl is brought to the physician for a well-child examination. Her mother says that she has been well except for an occasional cold. Her immunizations are up to date. She is at the 50th percentile for height and 60th percentile for weight. Physical examination shows breast bud development and a few pubic hairs. The mother asks whether her daughter's development is normal. Which of the following is the most appropriate initial response by the physician?
A) "I am concerned that your daughter may have precocious puberty."
B) "I think that your daughter is likely to begin menstruating in the next few months."
C) "I would like to order laboratory studies to ensure that your daughter's development is normal."
D) "Your daughter's breast development is somewhat less than might be expected for her age."
E) "Your daughter's development is normal."

Here we see Tanner-2 (10-11,5 y.o.), hypothyroidism(?)
 

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This question is not clear for me. I've answered C and got incorrect.
An 8-year-old girl is brought to the physician for a well-child examination. Her mother says that she has been well except for an occasional cold. Her immunizations are up to date. She is at the 50th percentile for height and 60th percentile for weight. Physical examination shows breast bud development and a few pubic hairs. The mother asks whether her daughter's development is normal. Which of the following is the most appropriate initial response by the physician?
A) "I am concerned that your daughter may have precocious puberty."
B) "I think that your daughter is likely to begin menstruating in the next few months."
C) "I would like to order laboratory studies to ensure that your daughter's development is normal."
D) "Your daughter's breast development is somewhat less than might be expected for her age."
E) "Your daughter's development is normal."

Here we see Tanner-2 (10-11,5 y.o.), hypothyroidism(?)
I would say A
 

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I chose the same answer. Some sources show tanner stage 2 for girls range from 8-15 yo, boys: 10-15 yo

I don't get this micro question.
26 month old boy with SOB & cough who had cutaneous abscesses caused by S. aureus. febrile, x-ray shows cavitary infiltrate of left lingula. Culture grows filamentous gram + rods. Answer choices are
A. Bacillus anthracis
B. Candida
C. Nocardia
D. Pneumocystis
E. Strep bovis

I think it's A but it's wrong. Any thoughts? Thanks.
answer is C nocardia filamentous gram positive rods
 

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a 3 year old boy has 1 week history of nonproductive cough wheezing nausea coarse bilateral crackles are heard on auscultation of the chest .stool culture shows 1.6cm roundworm larwa,chest xray shows bilateral infiltratethis disease was most likely cause by ingestion of which of the following? A) feces contaminated soil b )improperly caned beans c )pork products (i select this one but its wrong) d) raw shrimp e) under cooked meat
 

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Discussion Starter · #48 ·
a 3 year old boy has 1 week history of nonproductive cough wheezing nausea coarse bilateral crackles are heard on auscultation of the chest .stool culture shows 1.6cm roundworm larwa,chest xray shows bilateral infiltratethis disease was most likely cause by ingestion of which of the following? A) feces contaminated soil b )improperly caned beans c )pork products (i select this one but its wrong) d) raw shrimp e) under cooked meat
A. Strongyloides stercoralis.
 

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Discussion Starter · #49 ·
This question is not clear for me. I've answered C and got incorrect.
An 8-year-old girl is brought to the physician for a well-child examination. Her mother says that she has been well except for an occasional cold. Her immunizations are up to date. She is at the 50th percentile for height and 60th percentile for weight. Physical examination shows breast bud development and a few pubic hairs. The mother asks whether her daughter's development is normal. Which of the following is the most appropriate initial response by the physician?
A) "I am concerned that your daughter may have precocious puberty."
B) "I think that your daughter is likely to begin menstruating in the next few months."
C) "I would like to order laboratory studies to ensure that your daughter's development is normal."
D) "Your daughter's breast development is somewhat less than might be expected for her age."
E) "Your daughter's development is normal."
Have anybody answered this question correctly in their test?
 

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a 3 year old boy has 1 week history of nonproductive cough wheezing nausea coarse bilateral crackles are heard on auscultation of the chest .stool culture shows 1.6cm roundworm larwa,chest xray shows bilateral infiltratethis disease was most likely cause by ingestion of which of the following? A) feces contaminated soil b )improperly caned beans c )pork products (i select this one but its wrong) d) raw shrimp e) under cooked meat


How is this Strongyloides ???
and it cant be cause strongyloides enters by larvae in soil penetrating sking which is not an option. Can anyone please answer this question ?
 

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Discussion Starter · #51 ·
a 3 year old boy has 1 week history of nonproductive cough wheezing nausea coarse bilateral crackles are heard on auscultation of the chest .stool culture shows 1.6cm roundworm larwa,chest xray shows bilateral infiltratethis disease was most likely cause by ingestion of which of the following? A) feces contaminated soil b )improperly caned beans c )pork products (i select this one but its wrong) d) raw shrimp e) under cooked meat

How is this Strongyloides ???
and it cant be cause strongyloides enters by larvae in soil penetrating sking which is not an option. Can anyone please answer this question ?
I don't have another ideas.

-roundworm larvae
-pneumonitis
Strongyloides fits most of other roundworms.
Trichinella spiralis may be ingested, but there would be muscle symptoms.

3 year-old child theoretically may ingest soil with larvae.
But, the size of larvae (1,6 cm) doesn't fit. :confused:
Necator americanus???
What are your suggestions?
 

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43. A 32 year old woman, gravida 4, para 0, aborta 3, delivers a female newborn at term with dysmorphic features and numerous organ anomalies. The mother has had multiple spontaneous abortions , and this is her first live newborn child. Which of the following is the most likely explanation for the abnormalities seen in this newborn?
A) Autosomal dominant inheritance
B) Autosomal recessive inheritance
C) Gonadal mosaicism
D) Submicroscopic deletion
E) Unbalanced chromosome rearrangement

Anybody know the answer to this. Please urgent i have an exam in a week.
 

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43. A 32 year old woman, gravida 4, para 0, aborta 3, delivers a female newborn at term with dysmorphic features and numerous organ anomalies. The mother has had multiple spontaneous abortions , and this is her first live newborn child. Which of the following is the most likely explanation for the abnormalities seen in this newborn?
A) Autosomal dominant inheritance
B) Autosomal recessive inheritance
C) Gonadal mosaicism
D) Submicroscopic deletion
E) Unbalanced chromosome rearrangement

Anybody know the answer to this. Please urgent i have an exam in a week.
E unbalanced chrosomal rearrangement (trisomies)
 

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x linked recessive disease is seen in aproximately 1/100,000 males which of the following is expected prevalance of heterozygous females
a 1 /1000 b 1/10,000 c 1/50,000 d 1/200,000 e 1/10,000,000
 

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Discussion Starter · #57 ·
x linked recessive disease is seen in aproximately 1/100,000 males which of the following is expected prevalance of heterozygous females
a 1 /1000 b 1/10,000 c 1/50,000 d 1/200,000 e 1/10,000,000
p2 + 2pq + q2.
In X-recessive among males q2 = q, because all males with trait are diseased males as well.
Heterezygous females (females with trait) are 2pq. p tends to one, so we have: 2*1*1/100000 = 1/50000.
 

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p2 + 2pq + q2.
In X-recessive among males q2 = q, because all males with trait are diseased males as well.
Heterezygous females (females with trait) are 2pq. p tends to one, so we have: 2*1*1/100000 = 1/50000.
in FA 2014 they say the frequency of an X linked recessive disease in males=q and in females =q2 ???????
 

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Discussion Starter · #59 ·
in FA 2014 they say the frequency of an X linked recessive disease in males=q and in females =q2 ???????
That's right. Among females in XR-diseases calculations are the same as in AR-diseases. Because female may be a carrier or diseased (XHXh or XhXh) - like in AR: Aa or aa.

frequency of female-carrier (XHXh) = 2pq; of diseased female = q2.

But males-carriers in XR-diseases are diseased males at the same time (XhY, there's no another variant, he is ill and carrier in one). So the only unit that is used in calculations - q.
Try to repeat it in Kaplan lecture notes. This type of question I met in the Kaplan QBank.

May be the following discussion will be useful (I don't remember where it's from):
Let q be the frequency of the recessive affected allele and p be the frequency of the dominant unaffected allele. Thus, the female recessive homozygote genotype frequency is q2, so:

q2 = 9% = 0.09
q = 0.3

Since the allele is on the X chromosome, the frequency of affected males is equal to the allele frequency, so the frequency of affected males is 0.3 (or 30%). Note that this means that of the males, 30% of them will be affected.

Since I am assuming there are only two alleles, then the sum of the frequencies of the alleles is one:

p + q = 1
p = 1 - q
p = 1 - 0.3
p = 0.7

So, the frequency of unaffected males is 0.7 (or 70%).

The dominant homozygotes (and recessive homozygotes) and carriers will all be females (since they have two X chromosomes), and the frequency of the females that are carriers is given by 2pq:

2pq = 2 x 0.7 x 0.3 = 0.42

In order to determine the frequency of the population that are carriers, we would need to know the the frequencies of males and females in the population. Then, we could calculate the frequency of carriers in the whole population by multiplying the frequency of carriers by the percentage of the population that are females. Note that the above number (0.42) is simply the frequency of females that are carriers, not the frequency of carriers in the whole population.
 

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21. A 35-year-old man comes to the physician because of a 6-month history of burning abdominal pain that occurs 1 to 2 hours After he eats. he also has had black stools for 2 days. Use of over the counter antacids and Histamine 2 (h2)-receptor blocking agents has not been effective in relieving his symptoms He is sweatlng profusely and has light-headedness when stands.His blood pressure is 105/70 mm/hg while sitting Physical examination shows epigastrIc tendemess A CT scan of the abdomen shows 1 cm mass in the pancreas. Immunohistochemical labeling of neoplastic CellS in a biopsy specimen is most likely to involve the use on antibodies directed to which which of the following substances ?

A) Amylase
B) Gastrin
C)Glucagon
D) Human pancreatic polypeptide
E) Insulin
F) Lipase
G) Serotonin
H) Somatostatin
I) vasoactive Intestinal polypeptide

i can seem to understand what time of Tumor this is Im confused if its a Gastrinoma or something else?

Any answers?
 
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