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Question 1
Incorrect
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An 80-year-old female complains of chest pain characteristic of angina. A dose of glyceryl trinitrate (GTN) is administered that resolves the chest pain rapidly. Which ONE of the following is released on the initial metabolism of GTN?
Your Answer: Cyclic GMP
Correct Answer: Nitrite ions
Explanation:Angina pectoris is the most common symptom of ischemic heart disease and presents with chest pain relieved by rest and nitro-glycerine. Nitrates are the first-line treatment to relieve chest pain caused by angina. The commonly used nitrates are: 1. Glyceryl trinitrate 2. Isosorbide dinitrate The nitrate drugs are metabolized in the following steps: 1. Release Nitrite ions (NO2-), which are then converted to nitric oxide (NO) within cells. 2. NO activates guanylyl cyclase, which causes an increase in the intracellular concentration of cyclic guanosine-monophosphate (cGMP) in vascular smooth muscle cells. 3. Relaxation of vascular smooth muscle.Although nitrates are potent coronary vasodilators, their principal benefit in the management of angina results from a predominant mechanism of venous dilation:- Bigger veins hold more blood- Takes blood away from the left ventricle- Lowers LVEDV (preload), LA pressure- Less pulmonary oedema → improved dyspnoea
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 2
Incorrect
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The most common type of adult leukaemia is chronic lymphocytic leukaemia (CLL). It develops as a result of lymphocyte clonal proliferation.Which of the following statements about CLL is CORRECT?
Your Answer: > 90% of cases are of T-cell lineage
Correct Answer: It is most commonly discovered as an incidental finding
Explanation:CLL (chronic lymphocytic leukaemia) is the most common type of chronic lymphoid leukaemia, with a peak incidence between the ages of 60 and 80. It is the most common type of leukaemia in Europe and the United States, but it is less common elsewhere. The CLL tumour cell is a mature B-cell with low immunoglobulin surface expression (IgM or IgD). The average age at diagnosis is 72 years, with only 15% of cases occurring before the age of 50. The male-to-female ratio is about 2:1. Over 80% of cases are identified by the results of a routine blood test, which is usually performed for another reason. Lymphocytic anaemia, thrombocytopenia, and normochromic normocytic anaemia are common laboratory findings. Aspiration of bone marrow reveals up to 95% lymphocytic replacement of normal marrow elements.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 3
Incorrect
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The following statements about cross-sectional studies are true EXCEPT?
Your Answer: They can be used to assess the prevalence of a condition
Correct Answer: They can be used to determine the relative risk of a condition
Explanation:The UK national census is an example of a cross-sectional study.Cross-sectional studies can be used to assess the prevalence of a condition, and support or refute inferences of cause and effect.Cross-sectional studies are observations of the frequency and characteristics of a disease in a given population at one particular point in time. Cross-sectional studies do not differentiate between cause and effect and also do not establish the sequence of events.Cross-sectional studies cannot be used to calculate the relative risk of a condition.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 4
Correct
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A 29-year-old female with chronic anaemia secondary to sickle cell disease is being transfused. A few minutes after starting the blood transfusion, she develops widespread itching with urticarial rash, wheezing, nausea and chest pain. Her BP reduces to 60/40 mmHg.What is the most appropriate treatment?
Your Answer: Stop the transfusion and administer adrenaline
Explanation:Anaphylaxis transfusion reaction occurs when an individual has previously been sensitized to an allergen present in the blood and, on re-exposure, releases IgE or IgG antibodies. Patients with anaphylaxis usually develop laryngospasm, bronchospasm, abdominal pain, nausea, vomiting, hypotension, shock, and loss of consciousness. The transfusion should be stopped immediately and the patient should be treated with adrenaline, oxygen, corticosteroids, and antihistamines.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 5
Correct
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A 70-year-old man has a resting tremor, rigidity, bradykinesia, and a shuffling gait. Parkinson's disease is caused by one of the following mechanisms:
Your Answer: Loss of dopaminergic neurons in the substantia nigra
Explanation:Parkinson’s disease (PD) is one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years and causing progressive disability that can be slowed but not halted, by treatment. The 2 major neuropathologic findings in Parkinson’s disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites. See the images below.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 6
Incorrect
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A 55-year-old woman was complaining of headaches. On examination, the patient is found to have weakness on the left side of her body and her eyes are deviated towards the right hand side. These are signs of damage to which of the following areas?
Your Answer: Occipital lobe
Correct Answer: Frontal lobe
Explanation:Some potential symptoms of frontal lobe damage can include loss of movement, either partial or complete, on the opposite side of the body. In the patient’s case, it is a result of motor cortex damage on the right side since her left side of the body is affected. The conjugate eye deviation symptom towards the side of the lesion is a result of damage to the frontal eye field.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 7
Correct
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A 24-year-old male presents to the Emergency Department with a three-day history of high-grade fever, headache and rash along with neck stiffness. On examination, Kernig's sign is positive, and you note a petechial rash over the trunk and limbs. Her vital signs show tachycardia and hypotension. Based on these findings, you diagnose sepsis secondary to meningitis. Which one of the following definitions of sepsis is currently accepted?
Your Answer: Life-threatening organ dysfunction caused by a dysregulated host response to infection
Explanation:In 2016 the SOFA guideline was introduced, also called the Sepsis-related Organ Failure Assessment, to make a sepsis diagnosis easier and prevent mortality. According to this guideline, sepsis was defined as a life-threatening organ dysfunction due to a dysregulated host response to infection. Septic shock was defined as a subset of sepsis in which the circulatory and metabolic abnormalities would lead to a greater risk of mortality than sepsis alone. Patients with septic shock would be clinically identified by a need for vasopressors to maintain MAP greater than 65 mmHg and serum lactate greater than two mmol/L.
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This question is part of the following fields:
- Pathology
- Pathology Of Infections
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Question 8
Correct
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What is the primary route of transmission of Neisseria Gonorrhoeae?
Your Answer: Sexually transmitted
Explanation:Neisseria gonorrhoeae is primarily spread by sexual contact or through transmission during childbirth. It causes gonorrhoea which is a purulent infection of the mucous membrane surfaces.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 9
Incorrect
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A 45-year-old African American male presents to your clinic complaining of swelling of his feet for the past six months. On examination, there is periorbital and pedal oedema. A 24-hour urine collection is ordered, which shows 8 g of protein. The serum cholesterol is ten mmol/L. You order a renal biopsy to confirm the diagnosis. Which one of the following findings are you most likely to see in this patient's biopsy?
Your Answer:
Correct Answer: Focal segmental glomerulosclerosis
Explanation:This patient has Nephrotic Syndrome confirmed by the presence of 1. Heavy proteinuria (greater than 3-3.5 g/24 hours)2. Hypoalbuminemia (serum albumin < 25 g/L)3. Generalised oedema (often with periorbital involvement)4. Severe hyperlipidaemia (total cholesterol is often > 10 mmol/L). Focal Segmental Glomerulosclerosis will be the most likely answer as it is the most common cause of Nephrotic Syndrome in African American adults. Minimal change disease is the most common cause of nephrotic syndrome in children. Membranous glomerulonephritis is the most common cause of Nephrotic Syndrome in Caucasian adults. In IgA nephropathy, patients will complain of cola-coloured urine. Mesangiocapillary glomerulonephritis presents with features of Nephritic Syndrome.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 10
Incorrect
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All of the following statements are correct with regards to protection of the gastric mucosa except which of the following?
Your Answer:
Correct Answer: NSAIDs directly stimulate increased parietal cell acid production.
Explanation:Prostaglandin production, which usually inhibits acid secretion and increases mucus and bicarbonate secretion, is inhibited by NSAIDs.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 11
Incorrect
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How is measles primarily transmitted:
Your Answer:
Correct Answer: Respiratory droplet route
Explanation:Measles belongs to the paramyxoviridae group of viruses. The incubation period is 7-18 days (average 10) and it is spread by airborne or droplet transmission. The classical presentation is of a high fever with coryzal symptoms and photophobia with conjunctivitis often being present. The rash that is associated is a widespread erythematous maculopapular rash. Koplik spots are pathognomonic for measles, and are the presence of white lesions on the buccal mucosa.Differential diagnoses would include:RubellaRoseola infantum (exanthem subitom)Scarlet feverKawasaki diseaseErythema infectiosum (5thdisease)EnterovirusInfectious mononucleosisDiagnosis can be confirmed by the following means:Salivary swab for measles specific IgMSerum sample for measles specific IgMSalivary swab for RNA detectionPossible complications include:Otitis mediaFebrile convulsionsPneumoniaBronchiectasisDiarrhoeaMeningitisEncephalitisImmunosuppressionSubacute sclerosing panencephalitisDeath
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 12
Incorrect
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A 23-year-old male presents to his family physician with the complaint of repeated episodes of abdominal pain and the passage of dark coloured urine every morning. He also reports increasing fatigue over the past several months. On examination, there are raised, painful red nodules over the skin of the back. Laboratory workup shows haemolytic anaemia, leukopenia and thrombocytopenia. Which one of the following disorders is this patient most likely to have?
Your Answer:
Correct Answer: Paroxysmal nocturnal haemoglobinuria
Explanation:Paroxysmal nocturnal haemoglobinuria is an acquired genetic disorder that causes a decrease in red blood cells due to a membrane defect that allows increased complement binding to RBCs, causing haemolysis. Patients complain of dark-coloured urine first in the morning due to haemoglobinuria secondary to lysis of red blood cells overnight. Thrombosis occurs, which affects hepatic, abdominal, cerebral and subdermal veins. Thrombosis of hepatic veins can lead to Budd-Chiari syndrome, thrombosis of subdermal veins can lead to painful nodules on the skin, and thrombosis of cerebral vessels can lead to stroke. The presence of dark urine in the morning only and at no other time differentiates this condition from other conditions.Multiple myeloma would present with bone pain, signs of radiculopathy if there were nerve root compression and a history of repeated infections. Patients with Non-Hodgkin Lymphoma would complain of enlarged lymph nodes, fatigue, fever, weight loss and a history of repeated infections. Acute lymphoblastic leukaemia presents more commonly in children than in adults. The patient would complain of bone pain, and on examination, there would be hepatosplenomegaly.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 13
Incorrect
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A 59-year-old man is complaining of pain in his perineal area, a recent onset of urinary frequency and urgency, fever, chills, and muscle aches. He has a long history of nocturia and terminal dribbling. On rectal examination you find an exquisitely tender prostate.Which of these antibacterial agents would be most appropriate in this case?
Your Answer:
Correct Answer: Ciprofloxacin for 14 days
Explanation:An acute focal or diffuse suppurative inflammation of the prostate gland is called acute bacterial prostatitis.According to the National Institute for Health and Care Excellence (NICE), acute prostatitis should be suspected in a man presenting with:A feverish illness of sudden onset which may be associated with rigors, arthralgia, or myalgia; Irritative urinary voiding symptoms; acute urinary retention; perineal or suprapubic pain and an exquisitely tender prostate on rectal examination.Treatment of acute prostatitis as recommended by NICE and the BNFare:Ciprofloxacin or ofloxacin for 14 daysAlternatively, trimethoprim can be used. Duration of treatment is still 14 days
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 14
Incorrect
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An X-ray of a 24-year-old female hockey player who arrives at the hospital with a left foot injury reveals an avulsion fracture of the fifth metatarsal tuberosity. Which of the following muscles is most likely responsible for the movement of the fractured fragment?
Your Answer:
Correct Answer: Fibularis brevis
Explanation:An avulsion fracture of the base of the fifth metatarsal happens when the ankle is twisted inwards. When the ankle is twisted inwards a muscle called the fibularis brevis contracts to stop the movement and protect the ligaments of the ankle. The base of the fifth metatarsal is where this muscle is attached. The group of lateral leg muscles that function to plantarflex the foot includes the fibularis brevis and the fibularis longus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 15
Incorrect
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Which of the following is NOT a feature characteristic of intravascular haemolysis:
Your Answer:
Correct Answer: Bilirubinuria
Explanation:Features of intravascular haemolysis include:haemoglobinaemia, methaemalbuminaemia, haemoglobinuria (dark urine) and haemosiderinuria
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This question is part of the following fields:
- Haematology
- Pathology
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Question 16
Incorrect
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Regarding ACE inhibitors, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Angiotensin-II receptor blockers are a useful alternative in patients who cannot tolerate ACE-inhibitors due a persistent cough.
Explanation:ACE inhibitors should be used with caution in patients of Afro-Caribbean descent who may respond less well; calcium channel blockers are first line for hypertension in these patients. ACE inhibitors have a role in the management of diabetic nephropathy. ACE inhibitors are contraindicated in pregnant women. ACE inhibitors inhibit the breakdown of bradykinin; this is the cause of the persistent dry cough. Blocking ACE also diminishes the breakdown of the potent vasodilator bradykinin which is the cause of the persistent dry cough. Angiotensin-II receptor blockers do not have this effect, therefore they are useful alternative for patients who have to discontinue an ACE inhibitor because of persistent cough.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 17
Incorrect
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You examine a 48-year-old woman's blood results and notice that her glucose level is elevated. When you tell her about it, she tells you that her doctor recently ran some tests and discovered that she has impaired glucose tolerance.Which of the following medications has not been linked to a reduction in glucose tolerance?
Your Answer:
Correct Answer: Amlodipine
Explanation:The following drugs have been linked to impaired glucose tolerance:Thiazide diuretics, e.g. BendroflumethiazideLoop diuretics, e.g. furosemideSteroids, e.g. prednisoloneBeta-blockers, e.g. atenolol
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 18
Incorrect
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What does the correlation coefficient r = 0 indicate with regards to linear relationships between two variables?
Your Answer:
Correct Answer: There is no correlation between two variables
Explanation:r = 0 if there is no correlation between two variables. The closer that r is to 0, the weaker the correlation.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 19
Incorrect
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What is the mechanism of action of penicillin antibiotics:
Your Answer:
Correct Answer: Inhibition of bacterial cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.The integrity of the ß-lactam ring is essential for antimicrobial activity. Many bacteria (including most Staphylococci) are resistant to benzylpenicillin and phenoxymethylpenicillin because they produce enzymes (penicillinases, ß-lactamases) that open the ß-lactam ring.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 20
Incorrect
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A 32-year old male patient has been diagnosed with meningococcal meningitis and was given appropriate treatments. Because he is a family man, he fears that he might transmit the infection to the rest of his family members. The causative agent of meningococcal meningitis is spread via what mode of transmission?
Your Answer:
Correct Answer: Respiratory droplet route
Explanation:N. meningitidis, the causative agent of meningococcal meningitis, is considered both a commensal and a pathogen. It can be found in the surfaces of mucous membranes such as the nasopharynx and oropharynx. With this, it can be transmitted from a carrier to a new host via respiratory droplet secretions.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 21
Incorrect
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You suspect that your patient with polycystic kidney disease has developed a berry aneurysm as a complication of his disease. The patient complains of a sudden, severe headache. You are guessing subarachnoid haemorrhage secondary to a ruptured berry aneurysm as the cause of his severe headaches. What is the most likely location of his aneurysm?
Your Answer:
Correct Answer: Anterior communicating artery
Explanation:One of the complications that polycystic kidney disease may cause is the development of a brain aneurysm. A berry aneurysm is the most common type of brain aneurysm. The Circle of Willis, where the major blood vessels meet at the base of the brain, is where it usually appears. The most common junctions of the Circle of Willis where an aneurysm may occur include the anterior communicating artery (35%), internal carotid artery (30%), the posterior communicating artery and the middle cerebral artery (22%), and finally, the posterior circulation sites, most commonly the basilar artery tip.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 22
Incorrect
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Which of the following is a physiological function that is mediated by a hormone released by the posterior pituitary:
Your Answer:
Correct Answer: Water retention
Explanation:Antidiuretic hormone (ADH), released by the posterior pituitary, acts on the kidneys to increase water permeability in the distal nephron allowing greater water reabsorption and concentration of urine. Prolactin, from the anterior pituitary, is responsible for milk production. The thyroid hormones, from the thyroid gland, are responsible for an increase in basal metabolic rate (stimulated by TSH from the anterior pituitary). FSH/LH, from the anterior pituitary, are responsible for maturation of egg and sperm. Calcitonin, from the thyroid gland, is responsible for decreasing calcium levels.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 23
Incorrect
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Which of the following is NOT an adverse effect of amitriptyline:
Your Answer:
Correct Answer: Hypokalaemia
Explanation:Adverse effects include:Antimuscarinic effects: Dry mouth, Blurred vision, Constipation, Urinary retention, Sedation, ConfusionCardiovascular effects: Heart block, Arrhythmias, Tachycardia, Postural hypotension, QT-interval prolongation, Hepatic impairment, Narrow-angle glaucoma
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 24
Incorrect
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In the emergency room, a 28-year-old woman complains of wobbly and slurred speech, is unable to do the heel-shin test, and has nystagmus. The following signs are most likely related to damage to which of the following areas:
Your Answer:
Correct Answer: Cerebellum
Explanation:Cerebellar injury causes delayed and disorganized motions. When walking, people with cerebellar abnormalities sway and stagger. Damage to the cerebellum can cause asynergia, the inability to judge distance and when to stop, dysmetria, the inability to perform rapid alternating movements or adiadochokinesia, movement tremors, staggering, wide-based walking or ataxic gait, a proclivity to fall, weak muscles or hypotonia, slurred speech or ataxic dysarthria, and abnormal eye movements or nystagmus.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 25
Incorrect
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A man working as a waiter cuts his arm on a glass while he was working. The palmaris longus muscle was damaged as a consequence of his injury.Which of the following statements regarding the palmaris longus muscle is considered correct?
Your Answer:
Correct Answer: It receives its blood supply from the ulnar artery
Explanation:The palmaris longus is a small, fusiform-shaped muscle located on the anterior forearm of the human upper extremity. The palmaris longus muscle is commonly present but may be absent in a small percentage of the population, ranging from 2.5% to 26% of individuals, depending on the studied population.The palmaris longus belongs to the anterior forearm flexor group in the human upper extremity. The muscle attaches proximally to the medial humeral epicondyle and distally to the palmar aponeurosis and flexor retinaculum. The blood supply to the palmaris longus muscle is via the ulnar artery, a branch of the brachial artery in the human upper extremity.The palmaris longus muscle receives its innervation via branches of the median nerve containing nerve roots C5-T1. Median nerve injury at or above the elbow joint (including brachial plexus and nerve root injury) can lead to deficits in the palmaris longus and other forearm flexor muscles, leading to weakened elbow flexion, wrist flexion, radial deviation, finger flexion, thumb opposition, flexion, and abduction, in addition to the loss of sensory function in the distribution of the median nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 26
Incorrect
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Where: Capillary hydrostatic pressure is (P c) Hydrostatic pressure in the interstices is (P I )Plasma oncotic pressure is (π p) Interstitial oncotic pressure is (π i)Which of the following formulas best represents fluid flow at the capillary bed?
Your Answer:
Correct Answer: Volume / min = (P c - P i ) - (π p - π i )
Explanation:Starling’s equation for fluid filtration describes fluid flow at the capillary bed.Filtration forces (capillary hydrostatic pressure and interstitial oncotic pressure) stimulate fluid movement out of the capillary, while resorption forces promote fluid movement into the capillary (interstitial hydrostatic pressure and plasma oncotic pressure). Although the forces fluctuate along the length of the capillary bed, overall filtration is achieved.At the capillary bed, there is fluid movement.The reflection coefficient (σ), the surface area accessible (S), and the hydraulic conductance of the wall (Lp) are frequently used to account for the endothelium’s semi-permeability, yielding:Volume / min = LpS [(Pc- Pi) – σ(πp– πi)]Volume /min = (Pc-Pi) – (πp–πi) describes the fluid circulation at the capillaries.Where:Pc= capillary hydrostatic pressurePi= interstitial hydrostatic pressureπp= plasma oncotic pressureπi= interstitial oncotic pressure
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 27
Incorrect
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A 30 year old man presents to ED after a road traffic accident. Free intraperitoneal fluid is found on FAST (Focussed assessment for sonography in trauma) done in the supine position. Which of these is most likely to be affected?
Your Answer:
Correct Answer: Hepatorenal recess
Explanation:Fluid accumulates most often in the hepatorenal pouch (of Morrison) in a supine patient. The hepatorenal pouch is located behind the liver and anterior to the right kidney and is the lowest space in the peritoneal cavity in the supine position.Although the vesicouterine and rectouterine spaces are also potential spaces for fluid accumulation, fluid accumulation in them occur in the erect position.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 28
Incorrect
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Which of the following is typically a cause of a normal anion gap metabolic acidosis:
Your Answer:
Correct Answer: Diarrhoea
Explanation:FUSEDCARS can be used to remember some of the causes of a normal anion gap acidosis:Fistula (pancreaticoduodenal)Ureteroenteric conduitSaline administrationEndocrine (hyperparathyroidism)DiarrhoeaCarbonic anhydrase inhibitors (e.g. acetazolamide)Ammonium chlorideRenal tubular acidosisSpironolactone
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This question is part of the following fields:
- Physiology
- Renal
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Question 29
Incorrect
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A 50-year-old man presents with headaches, lethargy, hypertension, and electrolyte disturbance. A diagnosis of primary hyperaldosteronism is made.Which biochemical pictures would best support this diagnosis?
Your Answer:
Correct Answer: Hypokalaemic metabolic alkalosis
Explanation:When there are excessive levels of aldosterone outside of the renin-angiotensin axis, primary hyperaldosteronism occurs. High renin levels will lead to secondary hyperaldosteronism. The classical presentation of hyperaldosteronism when symptoms are present include:HypokalaemiaMetabolic alkalosisHypertensionNormal or slightly raised sodium levels
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 30
Incorrect
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At rest, skeletal muscle accounts for between 15-20% of cardiac output and accounts for around 50% of body weight. This can increase to nearly 80% of cardiac output during exercise. Skeletal muscle circulation is highly controlled and has a number of specialized adaptations as a result of this high degree of disparity during exercise, in combination with the diversity in the size of skeletal muscle around the body.What is the primary mechanism for boosting skeletal muscle blood flow during exercise?
Your Answer:
Correct Answer: Metabolic hyperaemia
Explanation:In skeletal muscle, blood flow is closely related to metabolic rate. Due to the contraction of precapillary sphincters, most capillaries are blocked off from the rest of the circulation at rest and are not perfused. This causes an increase in vascular tone and vessel constriction. As metabolic activity rises, this develops redundancy in the system, allowing it to cope with greater demand. During exercise, metabolic hyperaemia, which is induced by the release of K+, CO2, and adenosine, recruits capillaries. Sympathetic vasoconstriction in the active muscles is overridden by this. Simultaneously, blood flow in non-working muscles is restricted, preserving cardiac output. During exercise, muscle contractions pump blood through the venous system, raising the pressure differential between arterioles and venules and boosting blood flow via capillaries.Capillary angiogenesis is evident when muscles are used repeatedly (e.g. endurance training). It is a long-term effect, not a quick fix for increased blood flow.The local partial pressure of alveolar oxygen is the primary intrinsic control of pulmonary blood flow (pAO2). Low pAO2 promotes arteriole vasoconstriction and vice versa. The hypoxic pulmonary vasoconstriction (HPV) reflex allows blood flow to be diverted away from poorly ventilated alveoli and towards well-ventilated alveoli in order to maximize gaseous exchange.
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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SESSION STATS - PERFORMANCE PER SPECIALTY
