UWorld Test 5/23/2014 Flashcards
What is presbyopia?
Age related condition in which lens becomes less flexible, ciliary muscles weaken, and unable to focus on near things.
What are examples of aromatase inhibitors? What is their clinical use?
Anastrazole, letrozole, exemastane. They inhibit conversion of androgens to estrogen and used in breast cancer. Aromatoase inhibitors are equivalent or superior to tamoxifen in breast cancer treatment.
Majority of patients with MG have what kind of mass>
thymoma / thymic hyperplasia
In patients with cryptorchidism, what are the FSH, inhibin B levels, sperm count and testosterone levels?
Cryptorhidism => high temperature => sensistive seminiferous tubules become atrophic and hyalized => low sperm count. Sertoli cells normally responsible for production of inhibiin B => lack of inhibin B => elevated FSH levels. Tesosterrone by leydig cells (insenstiive to temperature) normal.
Effect of epinephrine
Adrenergic agonist. Per First Aid beta>alpha. Per uworld, affects alpha1, beta 1 and beta 2. alpha1 stimulation => vasoconstriction, beta 1 stimulation => contractility and heart rate, beta 2 stimulation => vasodilation. At high doses, alpha effects dominate, at low concentrations beta2>alpha 1
Effect of propanolol
beta 1 and beta 2 blocker, decreases blood pressure and heart rate
Berger Disease?
neprhotic symdrome: LM - mesangial proliferation IF: IgA deposits in mesangium, EM - mesangial IC depsoits. Occurs a couple of days after URI or acute gastroenteritis. Episodic hematuria with casts. If involved with other organs - HSP
Isonaizid MOA? Use? Toxicity?
Exact mechanism unknown but decreased synthesis of mycolic acids. Needs to be activated by bacterial catalase peroxidage (KatG). Used in TB. Also used as propylaxis - TB. Toxicity - injures neurons and hepatocytes. Give pyridoxine (B6) to prevent neurotoxicity
Trigeminal nerve arises from?
level of MCP and lateral aspect of the mid-pons
Methotrexate MOA , Use, Toxicity?
Methotrexate - inhibits dihydrofolate reductase - folic acid analog - deceases dTMP and DNA synthesis. Uses: cancer: Leukemia, lymphoma, choriocarcinonomas, sarcomas. Non-neoplastic: abortion, ectopic pregnancy, rheumatoid arthritis, psoriasis, IBD. Tox: myelosupression, hepatotoxicity - macrovesicular fatty change in liver - mucositis (painful mouth ulcers- stomatitis), pulmonary fibrosis. teratogenic
What imaging test is done to diagnose acute cholecystitis
Failed gallbladder visualization on radionuclide biliary scan
Distinguishing features between MAC and My TB?
MAC grows well at high temperatures (41 degrees). MAC also has predliction for reticuloendothelial system infection as well and patients with ppt with hepatosplenomegaly and anemia
MAC infection prophyslaxis in HIV patients - what CD4 levels and drug?
CD4<50 cells/mm3 and azithromycin
What enzyme is responsible for the production of epinephrine? It is under the influence of?
PNMT, cortisol
Spasticity - initial jerking resistence to passive extension followed by sudden release of resistance is characteristic of>
UMNL
