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Question 1
Incorrect
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A 4-year-old boy inserts a crayon into his external auditory meatus. Attempts to remove it have not been successful. What is the best course of action?
Your Answer: Enlist the help of additional staff members to restrain the child before attempting to remove it again in the emergency department
Correct Answer: Operate on the next emergency operating list
Explanation:The removal of foreign bodies from the ear is a common procedure in the emergency department.
Abandon attempts to retrieve a foreign body if complications arise. If the object migrates farther into the canal or if bleeding, oedema, or increasing pain develops, consult an ENT specialist. Repeated attempts to remove a foreign body from the ear may result in infection, perforation, or another morbidity.
The presence of a tympanic membrane (TM) perforation, contact of a foreign body with the tympanic membrane, or incomplete visualization of the auditory canal are indications for urgent-emergent ENT consultation for removal by operative microscope and speculum.
Local anaesthesia is invasive and is not generally used for uncomplicated ear foreign body removal because of the complex innervations of the external ear canal. -
This question is part of the following fields:
- Generic Surgical Topics
- Paediatric Surgery
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Question 2
Incorrect
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Out of the following options, which malignancy has the highest potential for multicentricity?
Your Answer: Wilms’ tumour of the kidney
Correct Answer: Transitional cell carcinoma
Explanation:Transitional cell carcinomas can arise anywhere in the urothelium lining the urinary tract; and hence are known to be multicentric and recur commonly. Prostatic adenocarcinoma most commonly involves the posterior lobe of the prostate gland. Although renal cell carcinomas occasionally show multicentricity, it is not common. Penile carcinomas are usually locally infiltrative lesions. Wilm’s tumours are usually solitary, but can be bilateral or multicentric in 10% cases. Small cell carcinoma of lung and teratomas are usually solitary.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 3
Incorrect
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A patients sciatic nerve has been severed following a stab injury. What would be affected?
Your Answer: The muscles in the anterior compartment of the leg would still be functional
Correct Answer: There would still be cutaneous sensation over the anteromedial surface of the thigh
Explanation:The sciatic nerve supplies nearly all of the sensation of the skin of the leg and the muscles of the back of the thigh, leg and foot. A transection of the sciatic nerve at its exit from the pelvis will affect all the above-mentioned functions except cutaneous sensation over the anteromedial surface of the thigh, which comes from the femoral nerve.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 4
Incorrect
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Which of the following is true about myasthenia gravis?
Your Answer: The patient should be given α-bungarotoxin to determine the number of acetylcholine binding sites at the post junctional membrane
Correct Answer: Response of skeletal muscle to nerve stimulation is weakened
Explanation:An autoimmune disorder, myasthenia gravis leads to progressive muscle weakness. It occurs due to formation of antibodies against the nicotinic acetylcholine (ACh) receptor of the motor endplate, which leads to impaired neuromuscular transmission. Thus, nerve stimulation will lead to a weakened muscle response, but direct electrical stimulation will bring about a normal response. Diagnostic test includes improvement of muscle weakness by small doses of acetylcholinesterase inhibitors (physostigmine or edrophonium). However, a large dose of physostigmine worsens the weakness due to desensitisation of the endplate to persistent Ach. One of the investigative tools includes radiolabelled snake venom α-bungarotoxin. It is an in vitro study performed on muscle biopsy specimens and used to quantify the number of ACh receptors at the motor endplate.
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This question is part of the following fields:
- Basic Sciences
- Physiology
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Question 5
Incorrect
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During an operation to repair an indirect inguinal hernia, it is noticed that the hernial sac is protruding out of the superficial inguinal ring. The superficial inguinal ring is an opening in which structure?
Your Answer: Transversalis fascia
Correct Answer: External abdominal oblique aponeurosis
Explanation:The superficial inguinal ring is an opening in the aponeurosis of the external oblique just above and lateral to the pubic crest. The opening is oblique and corresponds to the fibres of the aponeurosis. It is bound inferiorly by the pubic crest, on either side by the margins of the opening in the aponeurosis and superiorly by the curved intercrural fibres.
The inferior crus is formed by the portion of the inguinal ligament that is inserted into the pubic tubercle.
The falx inguinalis is made of arching fibres of the transversalis fascia and the internal abdominal oblique muscle. It forms the posterior wall of the inguinal canal.
The internal abdominal oblique forms the root of the inguinal canal.
Scarpa’s and Camper’s fascia are the membranous and fatty layers, respectively of subcutaneous fascia.
Transversalis fascia covers the posterior surface of the rectus abdominis muscle inferior to the arcuate line. -
This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 6
Incorrect
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Etoposide is a chemotherapeutic agent used in the treatment of different types of cancer. Which of the following is the correct indication for this drug?
Your Answer: Breast cancer
Correct Answer: Lung cancer
Explanation:Etoposide phosphate is an inhibitor of the enzyme topoisomerase II. It is used as a form of chemotherapy for malignancies such as lung cancer, testicular cancer, lymphoma, non-lymphocytic leukaemia and glioblastoma multiforme. Side effects are very common and can include low blood cell counts, vomiting, loss of appetite, diarrhoea, hair loss, and fever.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 7
Correct
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A 32 year old presents with symptoms of an anal fistula. The clinician examines him in the lithotomy position and the external opening of the fistula is identified in the 7 o'clock position. At which of the following locations is the internal opening most likely to be found?
Your Answer: 6 o'clock
Explanation:Goodsall’s rule can be used to clinically predict the course of an anorectal fistula tract. Imagine a line that bisects the anus in the coronal plane (transverse anal line). Any fistula that originates anterior to the line will course anteriorly in a direct route. Fistulae that originate posterior to the line will have a curved path. An exception to the rule are anterior fistulas lying more than 3 cm from the anus, which may open into the anterior midline of the anal canal.
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This question is part of the following fields:
- Colorectal Surgery
- Generic Surgical Topics
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Question 8
Incorrect
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During gastrectomy, the operating surgeon ligates the short gastric arteries along the greater curvature of the stomach. Where do the short gastric arteries branch from?
Your Answer: Left gastroepiploic artery
Correct Answer: Splenic artery
Explanation:Short gastric arteries arise from the splenic artery at the end or from its terminal divisions. They are about 5 or 7 in number, passing from the left to the right in between the layers of the gastrosplenic ligament to be distributed along the greater curvature of the stomach.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 9
Incorrect
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A 34 year old woman underwent a wide local excision for her breast carcinoma. Histology reveals an invasive lobular carcinoma present at three of the resection margins. Cavity shavings that were taken at the original operation are also involved. The sentinel lymph node biopsy was reported to be negative. Which of the following management plans would be the most appropriate for this patient?
Your Answer: Arrange for breast radiotherapy alone
Correct Answer: Arrange for completion mastectomy alone
Explanation:Mastectomy should ideally be done in this patient. This patient has extensive spread of disease and tumour margins are unclear which makes radiotherapy the less likely option. Mastectomy is the safest option in this scenario. Patients who have undergone mastectomy may be offered a reconstructive procedure either in conjunction with their primary resection or as a staged procedure at a later date.
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This question is part of the following fields:
- Breast And Endocrine Surgery
- Generic Surgical Topics
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Question 10
Incorrect
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A 32 year old woman who works as a teacher presents with a swollen, oedematous leg. She hails from Africa, from an area that is poorly sanitized and prevalent with mosquitoes. She travelled to England two weeks back. Which of the following is the most likely diagnosis?
Your Answer: Malaria
Correct Answer: Filariasis
Explanation:Lymphatic filariasis, commonly known as elephantiasis, is a painful and profoundly disfiguring disease. In communities where filariasis is transmitted, all ages are affected. While the infection may be acquired during childhood its visible manifestations may occur later in life, causing temporary or permanent disability. The disease is caused by three species of thread-like nematode worms, known as filariae – Wuchereria bancrofti, Brugia malayi and Brugia timori. Male worms are about 3–4 centimetres in length, and female worms 8–10 centimetres. The male and female worms together form “nests” in the human lymphatic system.
Filarial infection can cause a variety of clinical manifestations, including lymphoedema of the limbs, genital disease (hydrocele, chylocele, and swelling of the scrotum and penis) and recurrent acute attacks, which are extremely painful and are accompanied by fever. The vast majority of infected people are asymptomatic, but virtually all of them have subclinical lymphatic damage and as many as 40% have kidney damage, with proteinuria and haematuria.
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This question is part of the following fields:
- Generic Surgical Topics
- Vascular
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Question 11
Incorrect
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When exposing the right saphenofemoral junction for flush-ligation of the saphenous vein, which of the following is the most likely to be seen passing through this opening?
Your Answer: Saphenous nerve
Correct Answer: Superficial external pudendal artery
Explanation:The saphenous opening is an oval opening in the fascia lata. It is covered by the cribriform fascia and It is so called because it is perforated by the great saphenous vein and by numerous blood and lymphatic vessels and the superficial external pudendal artery pierces it.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 12
Correct
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Which of these foramen is located at the base of the skull and transmits the accessory meningeal artery?
Your Answer: Foramen ovale
Explanation:At the base of the skull the foramen ovale is one of the larger of the several holes that transmit nerves through the skull. The following structures pass through foramen ovale: mandibular nerve, motor root of the trigeminal nerve, accessory meningeal artery, lesser petrosal nerve, a branch of the glossopharyngeal nerve, emissary vein connecting the cavernous sinus with the pterygoid plexus of veins and occasionally the anterior trunk of the middle meningeal vein.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 13
Correct
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A 5-year-old child diagnosed with nephrotic syndrome developed generalised oedema. What is the mechanism for the development of oedema in patients with nephrotic syndrome?
Your Answer: Decreased colloid osmotic pressure
Explanation:The development of oedema in nephrotic syndrome has traditionally been viewed as an underfill mechanism. According to this view, urinary loss of protein results in hypoalbuminemia and decreased plasma oncotic pressure. As a result, plasma water translocates out of the intravascular space and results in a decrease in intravascular volume. In response to the underfilled circulation, effector mechanisms are then activated that signal the kidney to secondarily retain salt and water. While an underfill mechanism may be responsible for oedema formation in a minority of patients, recent clinical and experimental findings would suggest that oedema formation in most nephrotic patients is the result of primary salt retention. Direct measurements of blood and plasma volume or measurement of neurohumoral markers that indirectly reflect effective circulatory volume are mostly consistent with either euvolemia or a volume expanded state. The ability to maintain plasma volume in the setting of a decreased plasma oncotic pressure is achieved by alterations in transcapillary exchange mechanisms known to occur in the setting of hypoalbuminemia that limit excessive capillary fluid filtration.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 14
Correct
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A 24-year old, lactating mother presents to the clinic with a tender, 1.5cm mass just below the right nipple, which shows multiple fissures. What finding is likely associated with her condition?
Your Answer: Staphylococcus aureus infection
Explanation:Breast abscess occur commonly in lactating mothers in the postpartum period due to cracking of the nipple. It is commonly caused due to Staphylococcus aureus infection. Fat necrosis usually results from trauma wherein an ill-defined mass is formed. Ductal carcinomas are malignant masses which are not tender usually, and rare in the young age group. Plasma cell mastitis affect women in an older age group. Sclerosing adenosis is a type of fibrocystic disease which can lead to a tender, cystic mass but no fissuring or cracks are seen in the nipple. Fibroadenoma and lipomas are non-tender, well-defined masses.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 15
Incorrect
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During a car accident, the side mirror shattered and a broken piece of glass severed the posterolateral aspect of the driver's neck. A physical examination reveals that the driver is unable to elevate the tip of his shoulder on the side that was injured. Which nerve was injured?
Your Answer: Thoracodorsal
Correct Answer: Accessory
Explanation:The tip of the shoulder is formed by the acromion of the scapula. This part is moved by the trapezius muscle which is innervated by the accessory nerve. Damage to this nerve therefore will prevent the patient from lifting the tip of the shoulder.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 16
Incorrect
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A 57 year old man, known case of schizophrenia, undergoes a cholecystectomy. He is administered metoclopramide for post operative nausea. Twenty minutes later, he presents with agitation, marked oculogyric crises and oromandibular dystonia. Which of the following drugs would most likely alleviate his symptoms?
Your Answer: Sulpiride
Correct Answer: Procyclidine
Explanation:An acute dystonic reaction is characterized by involuntary contractions of muscles of the extremities, face, neck, abdomen, pelvis, or larynx in either sustained or intermittent patterns that lead to abnormal movements or postures. The symptoms may be reversible or irreversible and can occur after taking any dopamine receptor-blocking agents.
The aetiology of acute dystonic reaction is thought to be due to a dopaminergic-cholinergic imbalance in the basal ganglia. Reactions usually occur shortly after initiation of an offending agent or an increased dose of a possible offending agent.
Anticholinergic agents and benzodiazepines, procyclidine are the most commonly used agents to reverse or reduce symptoms in acute dystonic reaction. Acute dystonic reactions are often transient but can cause significant distress to the patient. Although rare, laryngeal dystonia can cause life-threatening airway obstruction. -
This question is part of the following fields:
- Post-operative Management And Critical Care
- Principles Of Surgery-in-General
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Question 17
Correct
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Regarding innervation to the peroneus brevis muscle:
Your Answer: Could be damaged by a fracture of the neck of the fibula
Explanation:The peroneus brevis is supplied by the fourth and fifth lumbar and first sacral nerves through the superficial peroneal nerve which is one of the two terminal branches of the common peroneal nerve. The common peroneal nerve winds around the neck of the fibula and can be injured in cases of fractured neck of fibula.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 18
Incorrect
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The transmembrane proteins responsible for resting membrane potential of vascular smooth muscle cells was blocked by a drug. Which of the following transmembrane proteins were blocked by this drug?
Your Answer: Na+/K+ pump
Correct Answer: K+ channels
Explanation:The resting membrane potential is due to selective permeability of the membrane to potassium ions. The Na/K pump is responsible for the generation of a gradient across the membrane and it is due to the inherent ability of the K channels to allow diffusion back into the nerve at rest which charges the cells. In reality, the resting membrane potential is more positive because of small contributions by Na+ channels, Cl− channels and non-selective cation channels.
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This question is part of the following fields:
- Basic Sciences
- Physiology
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Question 19
Incorrect
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Which of the following is a true statement regarding secretion of gastric acid?
Your Answer: Somatostatin increases gastric acid secretion
Correct Answer: Acetylcholine increases gastric acid secretion
Explanation:Gastric acid secretion is increased by acetylcholine, histamine and gastrin, with the help of cAMP as a secondary messenger. They increase H+ and Cl- secretion by increasing the number of H+/K+ ATPase molecules and Cl- channels. In contrast, gastric acid secretion is decreased by somatostatin, epidermal growth factor and prostaglandins.
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This question is part of the following fields:
- Basic Sciences
- Physiology
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Question 20
Correct
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Tumours derived from all three germ-cell layers in new-borns usually occur in which of the following sites?
Your Answer: Sacrococcygeal area
Explanation:A teratoma is a tumour with tissue or organ components resembling normal derivatives of more than one germ layer. It is derived from all three cell layers. The most common location of teratoma in new-born infants is in the sacrococcygeal area.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 21
Incorrect
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A 20 year old male presents to the clinic with progressive pain in his neck and back which has gotten worse over the past 7 months. Past medical history shows that he was an inpatient with a disease flare of ulcerative colitis. He is seen on examination with a stiff back and limited spinal extension on bending forward. What is the diagnosis?
Your Answer: Scheuermanns disease
Correct Answer: Ankylosing spondylitis
Explanation:Answer: Ankylosing spondylitis
Ankylosing spondylitis (AS), a spondyloarthropathy, is a chronic, multisystem inflammatory disorder involving primarily the sacroiliac (SI) joints and the axial skeleton. Key components of the patient history that suggest AS include the following:
Insidious onset of low back pain – The most common symptom
Onset of symptoms before age 40 years
Presence of symptoms for more than 3 months
Symptoms worse in the morning or with inactivity
Improvement of symptoms with exerciseGeneral symptoms of AS include the following:
Those related to inflammatory back pain – Stiffness of the spine and kyphosis resulting in a stooped posture are characteristic of advanced-stage AS.
Peripheral enthesitis and arthritis
Constitutional and organ-specific extra-articular manifestations
Fatigue is another common complaint, occurring in approximately 65% of patients with AS. Increased levels of fatigue are associated with increased pain and stiffness and decreased functional capacity.
Pharmacologic therapyAgents used in the treatment of AS include the following:
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Sulfasalazine
Tumour necrosis factor-α (TNF-α) antagonists
CorticosteroidsAS is the prototype of the spondyloarthropathies, a family of related disorders that also includes reactive arthritis (ReA), psoriatic arthritis (PsA), spondyloarthropathy associated with inflammatory bowel disease (IBD), undifferentiated spondyloarthropathy (USpA), and, possibly, Whipple disease and Behçet disease (see the image below). The spondyloarthropathies are linked by common genetics (the human leukocyte antigen [HLA] class-I gene HLA-B27) and a common pathology (enthesitis). The aetiology of AS is not understood completely; however, a strong genetic predisposition exists. A direct relationship between AS and the HLA-B27 gene has been determined. The precise role of HLA-B27 in precipitating AS remains unknown; however, it is believed that HLA-B27 may resemble or act as a receptor for an inciting antigen (e.g., a bacterial antigen).
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This question is part of the following fields:
- Generic Surgical Topics
- Orthopaedics
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Question 22
Incorrect
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Medulloblastoma usually occurs in children between 5 to 9 years old. Where does medulloblastoma commonly originate from?
Your Answer: Filum terminale
Correct Answer: Cerebellar vermis
Explanation:Medulloblastoma is the most common malignant brain tumour in children, accounting for 10-20% of primary CNS neoplasms. Most of the tumours originate in the cerebellar vermis.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 23
Incorrect
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One of the following structures is contained in the anterior compartment of the lower leg. Which is it?
Your Answer:
Correct Answer: Extensor hallucis muscle
Explanation:The lower leg is made up of four fascial compartments separated from one another by septa that contain the muscles of the lower leg. The four compartments are ; anterior, lateral, deep posterior and superficial posterior compartments.
These are the compartments and there contents:
i) Anterior compartment: Tibialis anterior muscle, extensor hallucis longus muscle, extensor digitorum longus muscle, peroneus tertius muscles, deep fibular nerve and anterior tibial blood vessels
ii) Lateral compartment: Fibularis longus muscle, brevis muscles and superficial fibular nerve
iii) Deep posterior compartment: Tibialis posterior m., flexor hallucis longus m., flexor digitorum longus m. ,popliteus m. , tibial nerve, posterior tibial artery and posterior tibial vessels such as the fibular artery.
iv) Superficial posterior compartment: Gastrocnemius m., soleus m., plantaris m., medial sural cutaneous nerve -
This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 24
Incorrect
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A 25-year-old female had a painful abdomen and several episodes of vomiting. She was severely dehydrated when she was brought to the hospital. Her ABG showed a pH 7.7, p(O2) 75 mmHg, p(CO2) 46 mmHg and bicarbonate 48 mmol/l. The most likely interpretation of this ABG report would be:
Your Answer:
Correct Answer: Metabolic alkalosis
Explanation:Metabolic alkalosis is a primary increase in bicarbonate (HCO3−) with or without compensatory increase in carbon dioxide partial pressure (Pco2); pH may be high or nearly normal. Metabolic alkalosis occurs as a consequence of a loss of H+ from the body or a gain in HCO3 -. In its pure form, it manifests as alkalemia (pH >7.40). As a compensatory mechanism, metabolic alkalosis leads to alveolar hypoventilation with a rise in arterial carbon dioxide tension p(CO2), which diminishes the change in pH that would otherwise occur. Normally, arterial p(CO2) increases by 0.5–0.7 mmHg for every 1 mmol/l increase in plasma bicarbonate concentration, a compensatory response that occurs very rapidly. If the change in p(CO2) is not within this range, then a mixed acid–base disturbance occurs. Likewise, if the increase in p(CO2) is less than the expected change, then a primary respiratory alkalosis is also present. However an elevated serum bicarbonate concentration can also occur due to a compensatory response to primary respiratory acidosis. A bicarbonate concentration greater than 35 mmol/l is almost always caused by metabolic alkalosis (as is the case in this clinical scenario). Calculation of the serum anion gap can also help to differentiate between primary metabolic alkalosis and the metabolic compensation for respiratory acidosis. The anion gap is frequently elevated to a modest degree in metabolic alkalosis because of the increase in the negative charge of albumin and the enhanced production of lactate. However, the only definitive way to diagnose metabolic alkalosis is by performing a simultaneous blood gases analysis, which reveals elevation of both pH and arterial p(CO2) and increased calculated bicarbonate.
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 25
Incorrect
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The primary area involved in the pathology of Parkinson's disease is:
Your Answer:
Correct Answer: Substantia nigra
Explanation:Parkinson’s disease is a degenerative, movement disorder of the central nervous system, and is typically characterized by muscle rigidity, tremor and bradykinesia (in extreme cases, akinesia). Secondary symptoms include high-level cognitive dysfunction and subtle language problems.
Parkinson’s disease is also called ‘primary Parkinsonism’ or ‘idiopathic Parkinson’s disease and is the most common cause of Parkinsonism, a group of similar symptoms. The disorder is caused due to loss of pigmented dopaminergic cells in the pars compacta region of the substantia nigra. -
This question is part of the following fields:
- Basic Sciences
- Physiology
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Question 26
Incorrect
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A 59 year old woman presents to the hospital with a 2.1cm mobile breast mass. A mammogram is indeterminate (M3), an ultrasound scan shows benign changes (U2), and clinical examination is also indeterminate (P3). What is the next best course of action?
Your Answer:
Correct Answer: Image guided core biopsy
Explanation:Image guided core biopsy (US-directed biopsy) is performed for lesions that are palpable, but also for non-palpable, mammogram-detected lesions with a corresponding abnormality visualized on US. US-guided core biopsy is technically easier than stereotactic-guided biopsy as real-time imaging allows the surgeon to visualize the biopsy as it occurs. Using sterile technique and local anaesthesia, a small puncture is made with an 11-knife blade and the needle is placed near the edge of the lesion and fired, which inserts it into the lesion for a sample to be retrieved. When placed parallel to the needle the position of the needle can be visualized on US.
If the core biopsy result is benign and is concordant with imaging findings, continued surveillance is acceptable. If the result is indeterminate or image-discordant, surgical excision is indicated to rule out malignancy. In order to determine the appropriate management and surveillance of a lesion, the histologic, imaging, and clinical findings must be taken into account for an assessment of concordance to be performed. In addition, surgical excision is indicated for a core biopsy that demonstrates atypical hyperplasia (lobular or ductal) or lobular carcinoma in situ or neoplasia as the incidence of coexisting ductal carcinoma in situ or invasive carcinoma may be as high as 30% due to potential sampling error.
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This question is part of the following fields:
- Breast And Endocrine Surgery
- Generic Surgical Topics
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Question 27
Incorrect
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A 28 year old teacher is readmitted following a difficult appendicectomy. On examination, her wound is erythematous and, on incision, foul smelling pus is drained. Which of the following organisms is responsible?
Your Answer:
Correct Answer: Bacteroides fragilis
Explanation:Bacteroides species are anaerobic bacteria that are predominant components of the bacterial florae of mucous membranes and are therefore a common cause of endogenous infections. Bacteroides infections can develop in all body sites, including the CNS, the head, the neck, the chest, the abdomen, the pelvis, the skin, and the soft tissues. Inadequate therapy against these anaerobic bacteria may lead to clinical failure.
These bacteria are resistant to penicillins, mostly through the production of beta-lactamase. Anaerobic bacteria can infect deep wounds, deep tissues, and internal organs where there is little oxygen. These infections are characterized by abscess formation, foul-smelling pus, and tissue destruction. Anaerobes outnumber aerobes by 1000:1 in the large intestine; thus, they play an important role in almost all intra-abdominal infections.
Secondary peritonitis and abdominal abscesses generally occur after entry of enteric organisms into the peritoneal cavity through perforation of the intestine or other viscus as a result of obstruction, infarction, or trauma.
Most visceral abscesses (e.g., hepatic), chronic cholecystitis, perforated and gangrenous appendicitis, postoperative wound infections and abscesses, diverticulitis, and any infection associated with faecal contamination of the abdominal cavity involve both aerobes and anaerobes.
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This question is part of the following fields:
- Clinical Microbiology
- Principles Of Surgery-in-General
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Question 28
Incorrect
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A 20-year old college student was diagnosed with meningitis that had developed due to an acute cavernous sinus thrombosis from an ear infection. Which of the following superficial venous routes is the usual path that an infected blood clot takes to reach the cavernous sinus?
Your Answer:
Correct Answer: Facial vein
Explanation:The facial vein is the usual communication between the cavernous sinus and the pterygoid sinus. It is through this vein that an infected clot can travel to the cavernous sinus and cause infection. The pterygoid plexus is a venous plexus that is situated between the temporalis muscle and lateral pterygoid muscle, and partly between the two pterygoid muscles. The pterygoid plexus is connected to the facial vein by the deep facial vein. This connection is what makes this area where this sinus and the facial vein are located a danger zone. The danger zone or triangle of the face is the area from the corners of the mouth to the nose bridge. The sinus connection in this area makes it possible for infection to reach the cavernous sinus and at times cause meningitis.
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This question is part of the following fields:
- Anatomy
- Basic Sciences
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Question 29
Incorrect
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A 69 Year old lady presented to the emergency department following a massive myocardial infarction. She was found to be in hypotensive shock with focal neurological signs. Unfortunately the patient demised. What would be the expected findings on the brain biopsy?
Your Answer:
Correct Answer: Liquefactive necrosis
Explanation:Liquefactive necrosis is often associated with bacterial or fungal infections. However, hypoxic death of cells within the central nervous system can also result in liquefactive necrosis. The focal area is soft with a liquefied centre containing necrotic debris and dead white cells. This may later be enclosed by a cystic wall
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This question is part of the following fields:
- Basic Sciences
- Pathology
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Question 30
Incorrect
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The blood-brain barrier is a membrane that separates the circulating blood from the brain extracellular fluid in the central nervous system (CNS). Which of the following statements regarding the blood– brain barrier is CORRECT?
Your Answer:
Correct Answer: It breaks down in areas of brain that are infected
Explanation:The blood–brain barrier is a membrane that controls the passage of substances from the blood into the central nervous system. It is a physical barrier between the local blood vessels and most parts of the central nervous system and stops many substances from travelling across it. During meningitis, the blood–brain barrier may be disrupted. This disruption may increase the penetration of various substances (including either toxins or antibiotics) into the brain. A few regions in the brain, including the circumventricular organs, do not have a blood–brain barrier.
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This question is part of the following fields:
- Basic Sciences
- Physiology
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SESSION STATS - PERFORMANCE PER SPECIALTY
