00
Correct
00
Incorrect
00 : 00 : 00
Session Time
00 : 00
Average Question Time ( Secs)
Retry this test Dashboard

  • Question 1 - A 72-year-old man presents with chest pain that is characteristic of angina. You...

    Incorrect

    • A 72-year-old man presents with chest pain that is characteristic of angina. You administer a dose of glyceryl trinitrate (GTN), which rapidly resolved his symptoms. Unfortunately, he also develops an unpleasant side effect.
      Which of the following side effects is he most likely to have developed? Select ONE answer only.

      Your Answer: Dry eyes

      Correct Answer: Headache

      Explanation:

      Nitrates are used in the treatment of angina pectoris and the prevention of myocardial ischaemia. Commonly used examples of nitrates are glyceryl trinitrate and isosorbide dinitrate. Unwanted effects, however, are common and can limit therapy, particularly when angina is severe or when patients are unusually sensitive to the effects of nitrates.
      The following are common or very common side effects of nitrates
      Arrhythmias
      Asthenia
      Cerebral ischaemia
      Dizziness
      Drowsiness
      Flushing
      Headache
      Hypotension
      Nausea and vomiting
      Diarrhoea, syncope and cyanosis can occur, but these are rare side effects. Dry eyes, bradycardia and metabolic acidosis have not been reported.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      3
      Seconds

  • Question 2 - A dermatological examination on a patient presenting with a lump shows a solid,...

    Incorrect

    • A dermatological examination on a patient presenting with a lump shows a solid, well circumscribed, lump measuring 0.8 cm in diameter.

      Which one of these best describes the lump you have found on examination?

      Your Answer:

      Correct Answer: Nodule

      Explanation:

      A nodule is a solid, well circumscribed, raised area that lies in or under the skin and measures greater than 0.5 cm in diameter. They are usually painless.

      A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter.

      A macule is a flat, well circumscribed area of discoloured skin less than 1 cm in diameter with no changes in the thickness or texture of the skin.

      A papule is a solid, well circumscribed, skin elevation measuring less than 0.5 cm in diameter.

      A plaque is a palpable skin lesion that is elevated and measures >1cm in diameter

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      0
      Seconds

  • Question 3 - All of the statements regarding vascular tone are correct except: ...

    Incorrect

    • All of the statements regarding vascular tone are correct except:

      Your Answer:

      Correct Answer: Most endogenous vasodilators act by decreasing levels of cAMP or cGMP.

      Explanation:

      Most vasoconstrictors bind to G-protein coupled receptors. These mediate elevation in intracellular [Ca2+] which leads to vascular smooth muscle contraction. Important vasoconstrictors include noradrenaline, endothelin-1 and angiotensin II.

      Increased intracellular Ca2+ is as a result of the release of Ca2+from the sarcoplasmic reticulum and depolarisation and entry of Ca2+via L-type voltage-gated Ca2+channels. Most types of vascular smooth muscle do not generate action potentials – instead, the depolarisation is graded, which allows graded entry of Ca2+.
      sequestration by the sarcoplasmic reticulum Ca2+ATPase, removal from the cell by a plasma membrane Ca2+ATPase and Na+/Ca2+exchange decreases intracellular Ca2+, resulting in vasodilation. Relaxation is a result of most endogenous vasodilators when there is an increase in cyclic guanosine monophosphate (cGMP) like nitric oxide) or cyclic adenosine monophosphate (cAMP) like prostacyclin and beta-adrenergic receptor agonists. These activate protein kinases causing substrate level phosphorylation.
      Clinically effective vasodilators are L-type Ca2+channel blocker drugs.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      0
      Seconds

  • Question 4 - A man suffered from a back injury due to a fall from a...

    Incorrect

    • A man suffered from a back injury due to a fall from a ladder. Significant bruising was found to be overlying his latissimus dorsi muscle.

      Which of the following statements regarding the latissimus dorsi muscle is considered correct?

      Your Answer:

      Correct Answer: It raises the body towards the arm during climbing

      Explanation:

      The latissimus dorsi muscle is a broad, flat muscle that occupies the majority of the lower posterior thorax. The muscle’s primary function is of the upper extremity but is also considered to be a respiratory accessory muscle.

      Latissimus dorsi is a climbing muscle. With the arms fixed above the head, it can raise the trunk upwards, together with the help of pectoralis major.

      Functionally, the latissimus dorsi muscle belongs to the muscles of the scapular motion. This muscle is able to pull the inferior angle of the scapula in various directions, producing movements on the shoulder joint (internal rotation, adduction and extension of the arm). It is innervated by the thoracodorsal nerve (C6 – C8) from the posterior cord of the brachial plexus, which enters the muscle on its deep surface.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      0
      Seconds

  • Question 5 - A 34-year-old man presented to the emergency room after being involved in a...

    Incorrect

    • A 34-year-old man presented to the emergency room after being involved in a road traffic accident. Upon observation and examination, it was noted that he was hypotensive and has muffled heart sounds. It was suspected that he has pericardial effusion, so an emergency pericardiocentesis was to be performed.

      In performing pericardiocentesis for suspected pericardial effusion, which of the following anatomical sites are at risk of being punctured?

      Your Answer:

      Correct Answer: 1 cm below the left xiphocostal angle

      Explanation:

      Pericardiocentesis is a procedure done to remove fluid build-up in the sac around the heart known as the pericardium. The pericardium can be tapped from almost any reasonable location on the chest wall. However, for the usual blind pericardiocentesis, the subxiphoid approach is preferred. Ideally, 2-D echocardiography is used to guide needle insertion and the subsequent path of the needle/catheter.

      In the subxiphoid approach, the needle is inserted 1 cm inferior to the left xiphocostal angle with an angle of 30 degrees from the patient’s chest with a direction towards the left mid-clavicle.

      The fingers may sense a distinct give when the needle penetrates the parietal pericardium. Successful removal of fluid confirms the needle’s position.

    • This question is part of the following fields:

      • Abdomen And Pelvis
      • Anatomy
      0
      Seconds

  • Question 6 - Which of the following statements about propofol is TRUE: ...

    Incorrect

    • Which of the following statements about propofol is TRUE:

      Your Answer:

      Correct Answer: Propofol has some antiemetic action.

      Explanation:

      Propofol has some antiemetic properties. It’s for this reason that it’s used to treat postoperative nausea and vomiting. Propofol is mostly processed in the liver, with the kidneys excreting just around 1% of it unaltered. Propofol, unlike thiopental, does not produce tissue necrosis when it is extravasated. Propofol lowers intracranial pressure via lowering brain metabolic rate and cerebral blood flow. Propofol is thought to be safe for people with bronchial asthma and chronic obstructive pulmonary disease.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
      0
      Seconds

  • Question 7 - A patient with abdominal pain, vomiting and bloody diarrhoea develops a low platelet...

    Incorrect

    • A patient with abdominal pain, vomiting and bloody diarrhoea develops a low platelet count and deranged renal function. A diagnosis of haemolytic uraemic syndrome is made.
      Which of the following organisms is a recognised cause of haemolytic uraemic syndrome? Select ONE answer only.

      Your Answer:

      Correct Answer: Escherichia coli

      Explanation:

      E.Colistrain 0157 causes enterohaemorrhagic diarrhoea and can be followed by haemolytic uraemic syndrome (renal failure, haemolytic anaemia and thrombocytopenia).

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      0
      Seconds

  • Question 8 - Pancreatic acinar digestive enzyme secretion is mainly stimulated by which of the following...

    Incorrect

    • Pancreatic acinar digestive enzyme secretion is mainly stimulated by which of the following hormones:

      Your Answer:

      Correct Answer: Cholecystokinin

      Explanation:

      Exocrine pancreatic secretion is controlled by:
      Parasympathetic stimulation which enhances secretion of both the enzyme and aqueous components
      Sympathetic stimulation which inhibits pancreatic secretion
      Secretin which stimulates secretion of the alkaline-rich fluid from ductal cells
      Cholecystokinin which stimulates secretion of the enzyme-rich fluid from acinar cells
      Somatostatin which inhibits secretion from both acinar and ductal cells
      Gastrin which stimulates pancreatic acinar cells to secrete digestive enzymes

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      0
      Seconds

  • Question 9 - What is the maximum strength of a scar versus unwounded skin: ...

    Incorrect

    • What is the maximum strength of a scar versus unwounded skin:

      Your Answer:

      Correct Answer: 0.8

      Explanation:

      Basic healing is complete by 5-10 days but maximal wound strength (80% of normal) may take 12 weeks.

    • This question is part of the following fields:

      • Pathology
      • Wound Healing
      0
      Seconds

  • Question 10 - Which of the following immunoglobulin molecules is the most abundant in secretions (such...

    Incorrect

    • Which of the following immunoglobulin molecules is the most abundant in secretions (such as saliva and breast milk):

      Your Answer:

      Correct Answer: IgA

      Explanation:

      IgA is the predominant antibody class in secretions and tremendous quantities are secreted into various body spaces and onto mucosal surfaces (the gut lumen, the pharynx and sinuses, the larger airways, although not the alveoli).
      Because of its size, the majority of IgM is found in the circulation.

      Along with IgM, IgD is predominant among the surface receptors of mature B cells, where it plays a key role in B cells activation.

      IgE has the lowest concentration in normal human serum. It plays a prominent role in immune responses to helminth parasites, and in allergic reactions.
      IgG is the most abundant immunoglobulin and constitutes 75 percent of serum immunoglobulin in an adult human

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      0
      Seconds

  • Question 11 - A 62-year-old woman is brought to the Emergency Department as she is acutely...

    Incorrect

    • A 62-year-old woman is brought to the Emergency Department as she is acutely unwell. Her attendants inform you that she was recently started on lithium as a mood stabilizer.

      You instantly send a blood sample to check for lithium levels.

      What is the usual therapeutic range for lithium?

      Your Answer:

      Correct Answer: 0.4-0.8 mmol/l

      Explanation:

      Lithium is the drug of choice for recurrent bipolar illness but should be carefully monitored as it has a very low therapeutic index. The normal therapeutic range is 0.4-0.8 mmol/l.

      The lower end of the range is usually the target for the elderly and as maintenance therapy. Toxicity is usually seen at levels >1.5 mmol/l. Samples should be taken 12 hours after the dose, and levels should be checked one week after starting therapy and one week after every change in dosage.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      0
      Seconds

  • Question 12 - A 42-year-old woman presents with face swelling prominently affecting her upper lip and...

    Incorrect

    • A 42-year-old woman presents with face swelling prominently affecting her upper lip and hands. She has previously been diagnosed with hereditary angioedema.

      Which of these is the most appropriate management option for this acute attack?

      Your Answer:

      Correct Answer: Fresh frozen plasma

      Explanation:

      Hereditary angioedema is inherited as an autosomal dominant disorder and is caused by deficiency of C1 esterase inhibitor, a protein that forms part of the complement system.

      Attacks can be precipitated by stress and minor surgical procedures. Clinical features of hereditary angioedema include oedema of the skin and mucous membranes commonly affecting the face, tongue and extremities.

      Angioedema and anaphylaxis due to a deficiency of C1 esterase inhibitor are resistant to adrenaline, steroids and antihistamines. Treatment is with fresh frozen plasma or C1 esterase inhibitor concentrate, which contains C1 esterase inhibitor.

      Short-term prophylaxis for events that may precipitate angioedema attack is achieved with C1 esterase inhibitor or fresh frozen plasma infusions before the event while long-term prophylaxis can be achieved with antifibrinolytic drugs (tranexamic acid) or androgenic steroids.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
      0
      Seconds

  • Question 13 - Regarding Clostridium species, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding Clostridium species, which of the following statements is INCORRECT:

      Your Answer:

      Correct Answer: They are facultative anaerobes.

      Explanation:

      Clostridium spp. are obligatory anaerobic spore-forming Gram-positive bacilli. Toxin production is the main pathogenicity mechanism.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      0
      Seconds

  • Question 14 - Which of the following tracts must be affected if a patient presents with...

    Incorrect

    • Which of the following tracts must be affected if a patient presents with decreased pain and temperature sensation in both lower extremities?

      Your Answer:

      Correct Answer: The lateral spinothalamic tract

      Explanation:

      The main function of the spinothalamic tract is to carry pain and temperature via the lateral part of the pathway and crude touch via the anterior part. The spinothalamic tract pathway is an imperative sensory pathway in human survival because it enables one to move away from noxious stimuli by carrying pain and temperature information from the skin to the thalamus where it is processed and transmitted to the primary sensory cortex. The primary sensory cortex communicates with the primary motor cortex, which lies close to it, to generate rapid movement in response to potentially harmful stimuli. Furthermore, the spinothalamic tract has a role in responding to pruritogens, causing us to itch. Interestingly, itching suppresses the spinothalamic tract neuron response to the histamine effect.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      0
      Seconds

  • Question 15 - You are instructed by a senior to administer Mannitol to an RTA patient...

    Incorrect

    • You are instructed by a senior to administer Mannitol to an RTA patient with increased intracranial pressure.

      Mannitol is a low molecular weight compound that freely filters at the glomerulus and is not reabsorbed.
      Out of the following, which is a contraindication to the use of mannitol?

      Your Answer:

      Correct Answer: Severe pulmonary oedema

      Explanation:

      Mannitol is the most widely used osmotic diuretic that is most commonly used to reduce cerebral oedema and intracranial pressure.
      It is recommended to use mannitol for the reduction of CSF pressure/cerebral oedema in a dose of 0.25-2 g/kg as an intravenous infusion over 30-60 minutes. This can be repeated 1-2 times after 4-8 hours if needed.

      Mannitol has several contraindications and some of them are listed below:
      1. Anuria due to renal disease
      2. Acute intracranial bleeding (except during craniotomy)
      3. Severe cardiac failure
      4. Severe dehydration
      5. Severe pulmonary oedema or congestion
      6. Known hypersensitivity to mannitol

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds

  • Question 16 - A 22-year-old man arrives at the emergency department with a sore throat, low-grade...

    Incorrect

    • A 22-year-old man arrives at the emergency department with a sore throat, low-grade fever, and malaise. His partner has infectious mononucleosis, which was recently diagnosed. In this situation, which of the following cells is the most proliferative:

      Your Answer:

      Correct Answer: Lymphocytes

      Explanation:

      Histologic findings in EBV infectious mononucleosis: Oropharyngeal epithelium demonstrates an intense lymphoproliferative response in the cells of the oropharynx. The lymph nodes and spleen show lymphocytic infiltration primarily in the periphery of a lymph node.
      Relative lymphocytosis (≥ 60%) plus atypical lymphocytosis (≥ 10%) are the characteristic findings of Epstein Barr virus (EBV) infectious mononucleosis.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      0
      Seconds

  • Question 17 - Which of the following statement is correct with regards to the female urethra?...

    Incorrect

    • Which of the following statement is correct with regards to the female urethra?

      Your Answer:

      Correct Answer: The urethra opens in the vestibule that lies between the labia minora.

      Explanation:

      The urethra in women is short (about 4 cm long), and begins at the base of the bladder. Its course runs inferiorly through the urogenital diaphragm, then into the perineum. It then opens in the vestibule which lies between the labia minora. The inferior aspect of the urethra is bound to the anterior surface of the vagina. The urethral opening is anterior to the vaginal opening in the vestibule. As the urethra passes through the pelvic floor, it is surrounded by the external urethral sphincter.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      0
      Seconds

  • Question 18 - A 7-days-old neonate is taken to the emergency department. She's pyretic, lethargic, and unresponsive, and...

    Incorrect

    • A 7-days-old neonate is taken to the emergency department. She's pyretic, lethargic, and unresponsive, and her fontanelle has bulged.  Antibiotics are started, and a lumbar puncture reveals Gram-negative rods. Which pathogen is most likely to be the cause:

      Your Answer:

      Correct Answer: Escherichia coli

      Explanation:

      Among neonates, group B streptococci (GBS) are the most commonly identified causes of bacterial meningitis, implicated in roughly 50% of all cases. Escherichia coli(Gram-negative rods) accounts for another 20%. Thus, the identification and treatment of maternal genitourinary infections is an important prevention strategy.

    • This question is part of the following fields:

      • Infections
      • Microbiology
      0
      Seconds

  • Question 19 - While on morning rounds in the medical ward, the attending physician asks a...

    Incorrect

    • While on morning rounds in the medical ward, the attending physician asks a medical student about the differences between transudates and exudates and their causes. The student explains that a transudate is an excess fluid that leaks out of an intravascular compartment due to an imbalance between oncotic and hydrostatic pressures.

      Which ONE of the following conditions will he mention as the cause of a transudate?

      Your Answer:

      Correct Answer: Meig’s syndrome

      Explanation:

      Transudative effusions are caused due to systemic causes leading to increased hydrostatic pressure or decreased oncotic pressure. These include:
      1) Meig’s Syndrome (Ovarian tumour causing ascites and pleural effusion)
      2) Congestive heart failure
      3) Nephrotic Syndrome
      4) Myxoedema
      5) Cirrhosis
      6) Sarcoidosis

      An exudate is caused by local inflammation and results from increased vascular permeability. Causes include:
      1) Rheumatoid arthritis
      2) Pneumonia leading to empyema
      3) Malignancies
      4) Pericarditis

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      0
      Seconds

  • Question 20 - A 58-year-old male has cellulitis of his left leg. Because he is allergic to...

    Incorrect

    • A 58-year-old male has cellulitis of his left leg. Because he is allergic to penicillin, you start him on erythromycin.

      What is erythromycin's mechanism of action?

      Your Answer:

      Correct Answer: Inhibition of protein synthesis

      Explanation:

      Bacteriostatic antibiotics include erythromycin and other macrolide antibiotics. They work by attaching to the bacterial ribosome’s 50S subunit, preventing translocation and thereby protein synthesis. Macrolide antibiotics are actively concentrated inside leukocytes and delivered to the infection site as a result.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      0
      Seconds

  • Question 21 - A 27 year old woman presents to ED having sustained a deep laceration...

    Incorrect

    • A 27 year old woman presents to ED having sustained a deep laceration to the dorsum of her ring finger whilst cooking. Her proximal interphalangeal joint is fixed in flexion and the distal interphalangeal joint is hyperextended. Which of the following structures in the digit has most likely been injured:

      Your Answer:

      Correct Answer: Insertion of the central slip of the extensor tendon

      Explanation:

      Damage to the central slip of the extensor digitorum tendon would result in loss of extension at the proximal interphalangeal joint resulting in a fixed flexion deformity of this joint, and hyperextension of the distal interphalangeal joint due to a loss of balancing forces. This is called the Boutonniere deformity.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      0
      Seconds

  • Question 22 - What is the main route of transmission of Mumps? ...

    Incorrect

    • What is the main route of transmission of Mumps?

      Your Answer:

      Correct Answer: Respiratory droplet route

      Explanation:

      Mumps is primarily transmitted person to person via respiratory droplets.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      0
      Seconds

  • Question 23 - Regarding macrolide antibiotics, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding macrolide antibiotics, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: Macrolides are first line for treatment of whooping cough.

      Explanation:

      A macrolide antibiotic is recommended first line for whooping cough (if onset of cough is within the previous 21 days)
      Prescribe clarithromycin for infants less than 1 month of age.
      Prescribe azithromycin or clarithromycin for children aged 1 month or older, and non-pregnant adults.
      Prescribe erythromycin for pregnant women.
      Macrolides interfere with bacterial protein synthesis and are mainly active against Gram-positive organisms. They have a similar antibacterial spectrum to penicillin and are thus a useful alternative in penicillin-allergic patients. Erythromycin is commonly associated with gastrointestinal upset.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      0
      Seconds

  • Question 24 - Regarding Clostridium difficile, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding Clostridium difficile, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: It is normally found in gut flora.

      Explanation:

      C. difficile is normally found in the gut flora but its growth is normally suppressed by more dominant anaerobes. It has exotoxin-mediated effects causing profuse diarrhoea. Oral clindamycin (a broad spectrum antibiotic) is commonly implicated in precipitating C. difficile colitis; first line treatment is with oral metronidazole. Tetanolysin is a toxin produced by Clostridium tetani bacteria.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      0
      Seconds

  • Question 25 - The renal team is currently prescribing erythropoietin to a patient with chronic kidney...

    Incorrect

    • The renal team is currently prescribing erythropoietin to a patient with chronic kidney disease.

      Which of the following statements about erythropoietin is correct?

      Your Answer:

      Correct Answer: It protects red blood cell progenitors from apoptosis

      Explanation:

      Erythropoietin is a glycoprotein hormone that regulates the formation of red blood cells (red cell production). It is mostly produced by interstitial fibroblasts in the kidney, which are located near the PCT. It is also produced in the liver’s perisinusoidal cells, however this is more common during the foetal and perinatal periods.

      The kidneys produce and secrete erythropoietin in response to hypoxia. On red blood cells, erythropoietin has two main effects:
      – It encourages stem cells in the bone marrow to produce more red blood cells.
      – It protects red blood cell progenitors and precursors from apoptosis by targeting them in the bone marrow.
      As a result of the increased red cell mass, the oxygen-carrying capacity and oxygen delivery increase.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      0
      Seconds

  • Question 26 - Normal saline (sodium chloride 0.9%) contains which of the following: ...

    Incorrect

    • Normal saline (sodium chloride 0.9%) contains which of the following:

      Your Answer:

      Correct Answer: Sodium and chloride

      Explanation:

      Normal saline (sodium chloride 0.9%) contains:
      Na+150 mmol/L
      Cl-150 mmol/L

    • This question is part of the following fields:

      • Fluids And Electrolytes
      • Pharmacology
      0
      Seconds

  • Question 27 - A patient with a high potassium level is at risk of going into...

    Incorrect

    • A patient with a high potassium level is at risk of going into cardiac arrest. What changes in the ECG may indicate the incident of cardiac arrest in this patient?

      Your Answer:

      Correct Answer: Peaked T waves and broad QRS complex

      Explanation:

      Severe hyperkalaemia can result in a heart attack or a life-threatening arrhythmia.

      T waves become narrow-based, pointed, and tall if hyperkalaemia is not treated.

      The QRS complex widens and eventually merges with the T wave, resulting in a classic sine-wave electrocardiogram. Ventricular fibrillation and asystole are likely to follow.

    • This question is part of the following fields:

      • Physiology
      • Renal
      0
      Seconds

  • Question 28 - Identify the type of graph described below:

    This graph is a useful tool for...

    Incorrect

    • Identify the type of graph described below:

      This graph is a useful tool for evaluating the performance of diagnostic tests and more generally for evaluating the accuracy of a statistical model (e.g., logistic regression, linear discriminant analysis) that classifies subjects into 1 of 2 categories, diseased or non diseased. The closer the graph is to the upper left corner, which represents 100% sensitivity and 100% specificity, the more accurate the diagnostic test.

      Your Answer:

      Correct Answer: ROC curve

      Explanation:

      Receiver-operating characteristic (ROC) analysis was originally developed during World War II to analyse classification accuracy in differentiating signal from noise in radar detection. Recently, the methodology has been adapted to several clinical areas heavily dependent on screening and diagnostic tests, in particular, laboratory testing, epidemiology, radiology, and bioinformatics. ROC analysis is a useful tool for evaluating the performance of diagnostic tests and more generally for evaluating the accuracy of a statistical model (e.g., logistic regression, linear discriminant analysis) that classifies subjects into 1 of 2 categories, diseased or non diseased. Its function as a simple graphical tool for displaying the accuracy of a medical diagnostic test is one of the most well-known applications of ROC curve analysis.

      The closer the ROC curve is to the upper left corner, which has 100% sensitivity and 100% specificity, the higher the overall accuracy of the diagnostic test.

    • This question is part of the following fields:

      • Evidence Based Medicine
      0
      Seconds

  • Question 29 - CSF is reabsorbed from subarachnoid space via which of the following structures: ...

    Incorrect

    • CSF is reabsorbed from subarachnoid space via which of the following structures:

      Your Answer:

      Correct Answer: Arachnoid granulations

      Explanation:

      From the subarachnoid cisterns in the subarachnoid space, CSF is reabsorbed via arachnoid granulations which protrude into the dura mater, into the dural venous sinuses and from here back into the circulation.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      0
      Seconds

  • Question 30 - Loop diuretics primarily act on which Na+ transporter? ...

    Incorrect

    • Loop diuretics primarily act on which Na+ transporter?

      Your Answer:

      Correct Answer: Na + /K + /2Cl - symporter

      Explanation:

      The most potent diuretics are loop diuretics e.g. furosemide. They work by inhibiting the Na+/K+/2Cl-symporter in the thick ascending limb of the loop of Henle, which inhibits sodium, potassium, and chloride reabsorption. As a result, there is diuresis with loss of these electrolytes. There is a reduction in transcellular voltage difference, paracellular calcium and magnesium reabsorption.
      The medullary interstitium becomes more concentrated by salt reabsorption in the ascending limb. Loop diuretics block this process and reduce the ability of the kidney to concentrate urine. In the collecting duct, there is increased sodium delivery to the principal cells, which increases potassium secretion in return for sodium reabsorption.

    • This question is part of the following fields:

      • Physiology
      • Renal
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Passmed
Retry this test Dashboard