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| kolsurgeon Total Posts: 13 | Posted: Fri Oct 24, 2008 05:16 am Compile all of your doubts in this thread. I will try and clear up as many as I can but doubts from surgery will get precedence since I am a general surgeon. Today, I will clarify one of the questions relating to the timing of switchover from HbF to HbA (which, unfortunately, netmedicos has given as the wrong answer). SWITCHOVER Switchover is defined as the time period when production of one type of Hb exceeds the rate of production of all other types. In the early period, embryonic Hb is synthesized. At around the 10-12 week period, the switchover from embryonic Hb to HbF occurs so that HbF is the form of Hb which has the maximal rate of synthesis during that time. Similarly, at around the 30-32 week period, switchover occurs from HbF to HbA which implies that HbA is the Hb that has the maximal rate of synthesis at that time leading to a right shift of the Hb-oxygen dissociation curve, an increase in P50 and oxygen releasing capacity. The closest is 36 weeks so the answer should have been this. This is not to be confused from the initiation of HbA which is synthesized very early in the fetal life! So, remember "switchover" implies to rate of synthesis. Hope this was useful to you all!  |
| kolsurgeon Total Posts: 13 | Posted: Fri Oct 24, 2008 05:18 am I forgot to mention the reference: it is taken from Textbook of Neonatal Medicine by Victor Hu et al! |
| bari Total Posts: 44 | Posted: Fri Oct 24, 2008 05:23 am sir kindly explain the best line of management of DCIS in postmenopausal women and why is stage I & II treated with simple mastectomy and not conservative surgery. ur help wll be valuable for me sir bari |
| kolsurgeon Total Posts: 13 | Posted: Fri Oct 24, 2008 05:58 am Hello Bari, The treatment of breast cancer has undergone a radical change over the last few years so has been the management of DCIS. Therefore, I would ask you to write down the question since there are a lot of treatment options for DCIS in postmenopausal women and I would explain the answer based on your question. About the second question, I did not get it fully. Did you mean Stage I and Stage II in postmenopausal women or associated with DCIS? |
| jemzcal Total Posts: 127 | Posted: Fri Oct 24, 2008 07:35 am Which type of hyperthyroidism shows raised uptake of I131? a goitrous b euthyroid c hypothalamic d schirmidt's node. please explain the basis for this q. thyroid is an often asked area and it will be of value to all of us. |
| dcmymx Total Posts: 42 | Posted: Fri Oct 24, 2008 07:46 am Q. During surgery ligation of which of the following small veins in the abdomen can lead to death of the patient..? a. IVC b. Sup mesen vein c. Coronary vein d. Splenic vein asked in manipal 2008 |
| superbdoc Total Posts: 273 | Posted: Fri Oct 24, 2008 04:04 pm Reduced salivary flow following irradiation is dose dependent. At what does does the flow reach essentially zero ? A) 4000 rads B) 5000 rads C) 6000 rads D) 7000 rads Which of the following substances is the most potent androgen ? A) Dihydroepiandrostendione B) Dihydrotestosterone C) Androstendione D) Testosterone |
| superbdoc Total Posts: 273 | Posted: Fri Oct 24, 2008 04:06 pm One more ..I hope u excuse me.. Person is protected from Hepatitis B infection if after immunisation the the level of anti HBs > (more than) a.0.5 IU/ml b.10 IU/ml c.5 IU/ml d.2 IU/ml |
| kolsurgeon Total Posts: 13 | Posted: Fri Oct 24, 2008 06:01 pm RADIOACTIVE IODINE UPTAKE TEST This test is now primarily used to differentiate between Graves Disease (goitrous hyperthyroidism) where diffuse uptake of radioiodine occurs within the thyroid from a toxic nodule where the uptake of radioiodine would be concentrated over a small region of the gland with suppression of the rest of the gland. This importance is that localized excision of the toxic nodule with preservation of the rest of the gland in a toxic nodule can lead to return of normal function but no in goitrous hyperthyroidism. Remember, I131 is now NOT USED for RAIU test. It is I123 that is used because of its smaller half life or 99mTc for RAIU. I131 is now used for thyroid ABLATION. Coming back to the question, goitrous hyperthyroidism would definitely show increased uptake of I131 so Choice A is definitely correct. Treated hyperthyroidism which is now in the euthyroid state would not result in increased I131 uptake as has been implied in Choice B so this is wrong. Hypothalamic hyperthyroidism: the existence of this state is dubious. Increased TRH levels are seen in clinical practice only in patients with various psychiatric illnesses and in patients taking certain psychiatric medications when a rise in TRH may be followed by a transient rise in thyroid hormones. However, nearly immediately, the pituitary TRH receptors downregulate so that prolonged exposure to increased TRH levels have absolutely no persistent effect on thyroid function. Thus, RAIU with I131 would not show increased uptake (it shows increased uptake only with persistently elevated function of the thyroid gland). So, choice C is wrong. I do not know what a "Schirmidt's node" is. Perhaps, if some of you can give me an idea about it I would then corelate the explanation but in any event the answer is Choice A! Hope this was helpful to you all! |
| superbdoc Total Posts: 273 | Posted: Fri Oct 24, 2008 09:36 pm I guess Obs ang Surgery are pretty much allied.. At 28 weeks gestation, amniocentesis reveals a AOD 450 of 0.20 which is at the top of third zone of the liley curve. The most appropriate management of such a case is ? A) Immediate delivery B) Intrauterine transfusion C) Repeat amniocentesis after 1 week D) Plasmapheresis |
| jemzcal Total Posts: 127 | Posted: Sat Oct 25, 2008 12:09 am thanks for the reply. It was apt and informative. I also dont know about schirmidt's node. i have searched onthe net also. But these were the choices given. it could be a printing error though. thanks once again. |
| kolsurgeon Total Posts: 13 | Posted: Sat Oct 25, 2008 04:42 am This is in reply to the accidental venous ligation question. I must say that the question is framed incorrectly because it is mentioned that accidental ligation of the following "small" veins....which is not true. Anyway, let us consider the choices. Superior mesenteric vein ligation can cause a dramatic fall in preload but the patient usually survives the acute episode. however, the degree of anastomotic pathways is not that much effective so that intestinal infarction occurs in most cases. therefore, a vein graft has been advocated. Coronary vein and splenic vein ligation have no effect on the individual. In fact, splenic vein ligation is routinely done in splenectomy and coronary vein ligation may be done in gastroesophageal varices with no untoward effect. The answer is therefore Inferior Vena Cava ligation or Choice A. Let us see what happens in IVC ligation. IVC ligation was routinely advocated earlier in patients suffering from pulmonary thromboembolism when the IVC filters were still not invented. Most of the patients survived the ligation and there was a low mortality. Chronically, the anastomotic pathways open up. In the acute phase a few patients might encounter phlegmasia cerulia dolens which can be reversed by thrombectomy. On the other hand, ligation of the SUPRADIAPHRAGMATIC IVC can cause death of the individual. This is due to the pooling of blood in the liver following the ligation which leads to irreversible shock. Release of the ligation leads to toxic products being released in the circulation which injure the myocardium leading to cardiogenic shock. This condition is usually irreversible. Therefore, considering the above facts, i would like to go in for IVC ligation as the answer! if anyone would like to add anything more he/she is most welcome! P.S. I am planning to take an exam in Jan so I might not be able to reply to your doubts fast! Also, I am now working as a surgical specialist so getting lesser time. However, keep posting your doubts, I would clear them whenever I get time! |
| kolsurgeon Total Posts: 13 | Posted: Sat Oct 25, 2008 06:18 am XEROSTOMIA "Xerostomia is the most common toxicity associated with standard fractionated radiation therapy to the head and neck. Acute xerostomia from radiation is due to an inflammatory reaction, while late xerostomia, which can occur up to one year after radiation therapy, results from fibrosis of the salivary gland and is usually permanent. Radiation causes changes in the serous secretory cells, resulting in a reduction in salivary output and increased viscosity of the saliva. A common early complaint following radiation therapy is thick or sticky saliva. The degree of permanent xerostomia depends on the volume of salivary gland exposed to radiation and the radiation dose. When the total radiation dose exceeds 5,200 cGy, salivary flow is reduced, and little or no saliva is expressible from the salivary ducts. These changes are typically permanent." Going by this excerpt, I would mark the answer as B. |
| kolsurgeon Total Posts: 13 | Posted: Sat Oct 25, 2008 06:27 am RELATIVE POTENCIES OF THE NATURAL ANDROGENS 5-alpha Dihydrotestosterone (DHT): 100% Testosterone (T): 50% Androstenedione (A4): 8% Dehydroepiandrosterone (DHEA): 4% Therefore, the answer is clearly DHT. |
| superbdoc Total Posts: 273 | Posted: Sat Oct 25, 2008 06:35 am thanx a ton...those answers are really precious for us... Requesting netmedicos administrator to include kolsurgeon in Netmedicos Experts group immediately.. |
| jemzcal Total Posts: 127 | Posted: Sat Oct 25, 2008 06:42 am I agree with superbdoc. kolsurgeon rocks. more doubts coming your way. 1)The most common cause of spasm of psoas in childhood is a) trauma b) tuberculosis psoas c) acute appendicitis d) pyogenic psoas abscess 20 which leucotriene is the adhesion factor for the neutrophil on the cell surface to attach endothelium a) B4 b) C4 c) D4 d) E4  |
| jemzcal Total Posts: 127 | Posted: Sat Oct 25, 2008 06:52 am 2 more surg. 1. A patient was operated 2 months back and at that time a midline inscicion was used. Now he requires a second operation and this the ideal incision to be used now is a. A fresh transverse incision b. The scar of the previous incision is excised and the same incision is used c. The same incision used without excision of old scar d. A paramedian incision is to be used 2. A child when playing had cat scratches over his hand. After 2 days he developed lymphadenopathy. Which group of the lymphnodes are involved if the scatches are over the region where the cephalic vein penetrates into the deeper fascia. a.Deltopectoral group b.Lateral group c.Clavipectoral group d.Central group |
| kolsurgeon Total Posts: 13 | Posted: Sat Oct 25, 2008 04:35 pm Anti-HBs antibody levels Let us see what Harrison has to say about this: "Currently, booster immunizations are not recommended routinely, except in immunosuppressed persons who have lost detectable anti-HBs or immunocompetent persons who sustain percutaneous HBsAg-positive inoculations after losing detectable antibody. Specifically, for hemodialysis patients, annual anti-HBs testing is recommended after vaccination; booster doses are recommended when anti-HBs levels fall to <10 mIU/mL." Still, if you have any doubts, here is another excerpt: "Briefly, the immune response to HBV vaccination can be assessed by determining the B cell responses (quantified in level of anti-HBs in serum). A serum antibody level above 10IU/l is defined as a protective response. The antibody level is highest in the months following vaccination, and decreases exponentially with time." I hope that there is no doubt now that the answer is Choice B! Cheers... |
| superbdoc Total Posts: 273 | Posted: Tue Oct 28, 2008 05:52 am Exhumation is usually done in ? A) Night B) Early morning C) Daytime D) Any time during the day |
| bari Total Posts: 44 | Posted: Tue Oct 28, 2008 10:02 pm exhumation is usually started in early morning and finshed in broad day light. principles of forensic medicine by APURBA NANDY 2nd edition PAGE 182. So i guess the answer should be early morning bari |
| superbdoc Total Posts: 273 | Posted: Wed Oct 29, 2008 12:25 am Thank you bari for that authentic answer...seems evry1s busy here.... 
Wish kolsurgeon returns soon...  |
| varuchinu Total Posts: 44 | Posted: Wed Oct 29, 2008 04:42 am The epidemiological marker for HBV is - a. Hbs Ag b. Hb c Ag c.anti Hbs Ag d. none |
| varuchinu Total Posts: 44 | Posted: Wed Oct 29, 2008 05:36 am True about ulcerative colitis in pregnancy- a.severity increases in 2 nd trimester b.severity increases in 3 rd trimester c.disease remains quiescent d.disease remains as such Thanks in advance |
| bari Total Posts: 44 | Posted: Wed Oct 29, 2008 07:44 am well a similar question was asked in AIIMS 2000 most useful epidemiological tool in HBV dr Rachna Chaurasia ARORA PUBLICATIONS has given the answer as anti Hbc as it is present in the window period and also indicates active(IgM) and remote(IgG) infection and it persists for life. so can be used for epidemiological purposes. anti HbsAg starts after 3-4 months of infection and persists for life and appear after HbsAg comes down after a window period so cannot be trusted as false negatives may occur uring window period.so option c ruled out. according to harrison 16th edition page 1820 - 1833 depending on HbsAg countries are divided into type I,II,III... but HbsAg does not persist for long and its dissapearanc heralds the onset of anti Hbs. so it cannot be useful once the active infection has come down.so option a ruled out. HbcAg cannot be detected in blood only anti Hbc(antibody) can be detected so option b ruled out. i would go for option d. bari |
| superbdoc Total Posts: 273 | Posted: Wed Oct 29, 2008 09:05 pm A patient of rheumatic heart disease with mitral stenosis and atrial fibrillation is on oral warfarin. On one OPD visit, his INR is found to be 6. What is the action to be taken ? A) Stop warfarin, and review B) Stop warfarin, and administer protamine sulphate C) Stop warfarin, and administer fresh frozen plasma D) Stop warfarin, and administer intramuscular vitamin K Please enlighten me with info reg this issue |
| bari Total Posts: 44 | Posted: Fri Oct 31, 2008 12:08 am treatment of choice in duodenal atresia 1. duodenojejunostomy 2. duodenoduodenostomy 3. medical management 4. none bailey and love 23rd edition gives answer as duodenojejunostomy but AAA gives the answer as duodenoduodenostomy and gives reference of Bailey & Love 24th ed and scwartz. some one plz help |
Total Posts: 7 | Posted: Fri Oct 31, 2008 03:38 am In an asymptomatic patient Warfarin is to be stopped if the INR >3.5 and <4.5 If INR >4.5 <9 then stop warfarin and administer sublingual Vit. K 1mg.If INR >9 then administer 2-3mg Vit. K sublingually. In a symptomatic patient Warfarin to be stopped and fresh frozen plasma to correct the bleeding. Reference Harrison 17th edt. |
Total Posts: 7 | Posted: Fri Oct 31, 2008 03:58 am Ulcerative colitis exacerbates in the 1st trimester and early post partum period. Since the question has no such option. We need to think otherwise. Not all pregnant ulcerative colitis patients have exacerbations therefore 'remains the same' could be taken as the answer;as remains quiescent means that the disease becomes inactive. Any other opinions?? Whereas Crohns disease exacerbates in the 2nd and 3rd trimester of pregnancy. |
Total Posts: 7 | Posted: Fri Oct 31, 2008 03:59 am Reference for the above reply is Harrison 17th edt. |