+- USMLE Forum - Largest USMLE Community (https://www.usmleforum.com)
+-- Forum: USMLE Forum (https://www.usmleforum.com/forumdisplay.php?fid=1)
+--- Forum: Step 1 (https://www.usmleforum.com/forumdisplay.php?fid=2)
+--- Thread: High-Yield Qs #2 - darth_vader (/showthread.php?tid=66301)
Pages:
1
2
High-Yield Qs #2 - darth_vader - ArchivalUser - 12-17-2005
Again, this is the questions that my friend had during the real. Hope this helps.
(1) How Cimetidine affects Aspirin™s Absorption ?
(2) Shigella vs. Salmonella why do they have different organisms needed to be infected?
(3) ER (+) Postmenopausal Breast Cancer pt. What Chemotherapy agent to use ?(there was no Tamoxifen or Raloxifen on the choice)
(4) Why does HbF has more affinity to Oxygen than HbA ?
(5) You gave antacid to 8 year old pt. and now the pt. has diarrhea. What is the most likely drug ?
( there was no magnesium hydroxide in the choice, but magnesium something was there, my friend said that it could have been magnesium sulfate , but he was not sure )
(6) Possible target for HIV Vaccine?
(7) How shigella cause diarrhea (not by shiga toxin)? (my friend said that question in the Qbank resembled this)
(8) What is the acting site of Lidocaine ?
(9) HIV nehritis
(10) Pathophysiologic mechanism of Dilated cardiomyopathy and Hypertrophied cardiomyopathy (My friend had 4~5 question about this topic again and again)
0 - ArchivalUser - 12-17-2005
1)ERDs, or "estrogen receptor downregulators," are a new type of hormonal treatment for breast cancer. In April 2002, the first ERD, called Faslodex (chemical name: fulvestrant), was approved by the U.S. Food and Drug Administration (FDA). The drug is approved for treating hormone-receptor-positive metastatic breast cancer in post-menopausal women with cancer that is no longer responding to hormonal therapy such as tamoxifen (brand name: Nolvadex).
http://www.breastcancer.org/tre_sys_hrt_erds.html
2)SERMs”selective estrogen receptor modulators”block the actions of estrogen in breast tissues and certain other tissues by "occupying" the estrogen receptors on cells. With a SERM sitting in the estrogen receptor, there is no place for the real estrogen to "sit down"”like a game of musical chairs. The SERM fits in the estrogen receptor, but it does NOT send messages to the cell nucleus to grow and divide.
Three of the most discussed SERMs are tamoxifen (brand name: Nolvadex), toremifene (brand name: Fareston), and raloxifene (brand name: Evista).
3) Herceptin (chemical name: trastuzumab) is a very effective treatment against HER2-positive breast cancer in women with stage II, III, and IV disease (medium to large cancers or cancers with lymph nodes involved or metastatic disease). It is given intravenously into the bloodstream once every one to three weeks. Women whose cancers are PR-positive but ER-negative may still respond to anti-estrogen therapy. In addition, a recent study suggests that the immune treatment Herceptin may be beneficial regardless of ER/PR status.
0 - ArchivalUser - 12-17-2005
1)aspirin absorption is decreased
cimetidine is an antacid increases ph of stomach.aspirin,an acidic drug which is primarily absorbed in the stomach becomes ionized in basic medium and its absorption is decreased.
4)were they asking for the physiological significance? if so,i think its b/c
.fetal blood has to get oxygen from maternal blood,and this can only be possiblr if hbF has higher affinity fo roxygen than hbA.then it can displace the O2 from hbA .
8)acting site of lidocaine--sodium channels in axonal membrane?
9)focal segmental glomerulosclerosis (FSGS)?
10)dilated CM--volume overload (regurgitant lesions)
hypertrophic CM--pressure overload(stenotic lesions)
0 - ArchivalUser - 12-17-2005
5)mesoprostol?
6)i think its gp120 and gp160
0 - ArchivalUser - 12-17-2005
For Q3, I asked the other friend who have finished Step1 and is about to take Step2. He said that if premenopausal pt. , you give SERMs if postmenopausal pt. , you give aromatase inhibitors (ex.anastrozole, letrozole, aminoglutethimide) But I had no idea about the recent drugs. Thank you usmle20 !
For Q8, My friend said that the Question was about Lidocaine as antiarrhthmics, not local anesthetics.
for Q10, Myfriend was saying something about molecular level pathologies, which I couldn't remember (I recall something of fibrils)
0 - ArchivalUser - 12-17-2005
Q8) lidocaine blocks fast sodium channels of SA nodal fibers.
0 - ArchivalUser - 12-17-2005
Phase I trials have been conducted with the full-length env gene product (gp160) or the envelope protein gp120 produced in insect cells, yeast or mammalian cells. The highest titer and most broadly reactive neutralizing antibodies were induced by the mammalian gp120 vaccines. However, the first vaccines were based on laboratory-adapted strains of HIV that used the CXCR4 receptor to enter T cells; the antibodies induced by these vaccines do not neutralize primary HIV isolates grown in PHA-stimulated peripheral blood mononuclear cells, which rely largely on CCR5 for entry into monocytic cells (Mascola). Two gp120 vaccines produced in mammalian cells have been evaluated in Phase II trials (McElrath). These vaccines are now being modified to include additional components derived from Thai or U.S. isolates; these vaccines will be evaluated to determine whether they induce antibodies that block infection via CCR5.
0 - ArchivalUser - 12-18-2005
about Q 8, would that be 'SA node' fibres or 'fast response' fibres? as far as i know class Ib, ie. lidocaine and the sorts, block inactivated SODIUM channels....sodium in itself would suggest they are fast response fibres.....correct me plz.
0 - ArchivalUser - 12-18-2005
i am sorry about that. that's fast response fibers.
thank you for correcting me gowest!!
0 - ArchivalUser - 12-18-2005
i will get ur back, u get mine;o)