2006a_Paper 1 – Medical Sciences

Of the following tumour markers, which has the highest specificity for the cancer indicated?

An immediate generalised reaction to which of the following drugs is most likely to be mediated by IgE (immunoglobulin E)?

A 52-year-old woman has been given a diagnosis of chronic fatigue syndrome (CFS) by her general practitioner. She meets Centres for Disease Control (CDC) criteria for this diagnosis. Which approach is most likely to be beneficial?

A 60-year-old man presents with nephrotic syndrome. He undergoes a renal biopsy. What is the most likely histological finding?

In addition to ondansetron and dexamethasone, the most effective strategy to reduce delayed chemotherapy nausea for someone receiving highly emetogenic chemotherapy is to add:

Which of the following factors is most predictive of future erosions in a patient with rheumatoid arthritis?

Oral medications, Drugs A and B, have the following properties in healthy individuals. Drug A Drug B Absorption 100% 100% Bioavailability 2% 90% Volume of distribution 350 L 50 L Renal Clearance 2 L/hr 1 L/hr Hepatic clearance 10 L/hr 2 L/hr Protein Binding 75% 25% Compared to healthy individuals, patients with cirrhosis have a much higher concentration of drug A than drug B. The best explanation for this is the difference in:

Which clinical feature of delirium is most useful for differentiating it from dementia?

A 56-year-old male presents with a three year history of progressive breathlessness on exercise with a dry unproductive cough. He works in a bank and has a ten pack year smoking history. His lung function is shown below. What is the most likely diagnosis?

Which of the following cells is most important in the pathogenesis of vasculitis in temporal arteritis?

Which of the following parameters is most likely to decrease in the first trimester of pregnancy?

Which of the following observations regarding a rare disorder would provide the best evidence of autosomal dominant inheritance?

A man with chronic renal failure is on the renal transplant waiting list. He is serologically cytomegalovirus (CMV) negative. If he is to receive a transplant from a CMV positive donor, which of the following is the most appropriate prophylactic regime for CMV disease?

In idiopathic pulmonary arterial hypertension, an excess of which of the following mediators is most likely to be involved in the pathogenesis?

A defect in elimination of which of the following is most likely to occur post-splenectomy?

Which of the following cells is most likely to cause bony erosions in patients with rheumatoid arthritis?

For which of the following cancers is screening most strongly associated with improved survival?

A 42-year-old man with schizo-affective disorder and long-standing use of lithium presents with polyuria. Which of the following parameters is most suggestive of psychogenic polydipsia as the cause of his polyuria?

A 40-year-old woman treated for Hodgkin’s disease in her early twenties with mantle radiotherapy is at highest risk of which of the following cancers?

Diabetic neuropathic arthropathy is most likely to affect which of the following areas?

Which one of the following patterns of electrolyte changes is most consistent with tumour lysis? Key to symbols: ↓ = decrease ↑ = increase

Liberation of dietary cobalamin from R-proteins would be most likely to be adversely affected by:

A 48-year-old male presents with a six-month history of daytime somnolence. He worked as a shipbuilder and had previous asbestos exposure from replacing boiler lagging. He has a 15 pack year smoking history. His body mass index (BMI) is 39 kg/m2 [18-26], but otherwise examination is normal. His lung function tests and arterial blood gas are shown above. The most likely diagnosis is:

What is the most distinguishing feature of loss of imprinting of a growth-promoting imprinted gene?

A 73-year-old man is referred for assessment of testamentary capacity. There is a past history of excessive alcohol consumption and hypertension. Over the last six months, he has been more forgetful and irritable with occasional socially inappropriate behaviour. His speech is fluent and comprehension normal. There are no focal neurological findings. Testamentary capacity can be best established by which of the following?

Which of the following best describes the toxicological mechanism of recurrent acute angioedema related to the use of angiotensin converting enzyme (ACE) inhibitors?

Which of the following drugs used in diabetes treatment is most likely to cause hypoglycemia?

In clinical research, which of the following best describes the meaning of the p value? The probability:

Hypomagnesemia is a common biochemical abnormality after renal transplantation and may cause serious cardiac arrhythmias. In this setting, it is most commonly due to:

A patient presents with weakness of the right hand and face, but sparing the leg. The most likely anatomic location of the stroke is:

A 35-year-old man presents with several weeks of generalised unwellness, epigastric pain, vomiting and headaches. He has no past medical history of note. He has a smoking history of 15 pack years and uses daily cannabis. He has been holidaying at the beach for the summer and is tanned. He is mildly dehydrated. The rest of the physical examination is unremarkable. Blood tests show: sodium 139 mmol/L [138-145] potassium 5.4 mmol/L [3.5-5.2] corrected calcium 3.10 mmol/L [2.15-2.57] phosphate 1.50 mmol/L [0.87-1.45] urea 10.4 mmol/L [3.5-8.0] creatinine 0.32 mmol/L [0.05-0.12] parathyroid hormone 0.6 pmol/L [1.6-6.2] His chest X-ray is shown below. What mechanism best explains the hypercalcaemia?

In a patient with rheumatic mixed mitral valve disease, for which of the following procedures is there the strongest indication for antibiotic prophylaxis?

A test has a sensitivity of 95% and a specificity of 80%. It is used to screen for a condition with a prevalence of 1 in 100. What will the positive predictive value be nearest to?

Arthritis in which of the following joints is most suggestive of haemachromatosis?

Defects in the terminal attack elements of the complement system (C6, C7, C8) are most strongly associated with an increased risk of infection with which of the following pathogens?

Which of the following is the most appropriate tumour marker for follow-up of a person with medullary thyroid carcinoma?

During normal haemostasis, von Willebrand factor (vWF) plays a role in platelet adhesion/aggregation. During this process, which of the following is the primary binding site of vWF to platelets?

Which of the following is most predictive of variceal haemorrhage in a patient with oesophageal varices?

Which of the following best explains why the jugular venous pressure (JVP) is raised in patients with congestive heart failure?

The 'number needed to treat' (NNT) to prevent one event is a clinically meaningful measure of the efficacy of treatment. When comparing event rates between two treatment groups in a clinical trial, the NNT is calculated as:

An 18-year-old male develops a rash and becomes critically ill. The rash is demonstrated above. The most likely finding on blood cultures would be:

Airline travel is undertaken by many patients with chronic cardio-respiratory disease. When travelling with standard international commercial airlines currently, the partial pressure of oxygen inflight approximates which sea-level FIO2 [Fraction of inspired oxygen]?

A 36-year-old woman has a very strong family history of premature coronary disease. Physical examination is normal. Fasting lipid profile reveals: total cholesterol 9.5 mmol/L [2.5-5.2] high-density lipoprotein (HDL) cholesterol 1.5 mmol/L [0.9-1.8] triglycerides 2.00 mmol/L [0.10-1.85] Which abnormality is most likely to be present?

A 66-year-old man presents with numbness involving the right thumb and index finger, and the first dorsal webspace and dorsoradial forearm. There is no associated neck pain. On examination, power is normal. The biceps and triceps reflexes are normal and symmetrical. The brachioradialis reflex is reduced on the right. The most likely diagnosis is:

In which of the following does mannose binding lectin (MBL) have the most significant role?

The emergence of a pandemic strain of influenza is best explained by which of the following mechanisms?

A man is diagnosed with a rare autosomal recessive disorder. His pedigree is shown below. What is the best estimate of the risk of his cousin (indicated on the diagram by an arrow) developing the same disorder?

Which of the following is most likely to affect interpretation of the pulmonary artery occlusion pressure trace?

The coupling of osteoblast and osteoclast function is mainly related to the action of which of the following factors?

Which one of the following statements is the best description of the molecular basis of a chimaeric protein (eg Bcr-Abl)?

Which of the following best explains the morphological appearance of red cells pictured below? Red Cell Parameters Haemoglobin 103 g/L [122-170] Haematocrit 0.30 [0.36-0.49] Mean corpuscular volume 83 fL [80-97] Mean corpuscular haemoglobin 28.3 pg [26.0-34.0] Mean corpuscular haemoglobin concentration 340 g/L [311-352] Red blood cells 3.64 x 1012/L [4.00-5.70]

Of the following antiplatelet actions, which best describes the mechanism of clopidogrel?

The primary factor leading to the accumulation of ascites in patients with chronic liver disease is?

The most common cause of treatment failure in pulmonary tuberculosis is:

High-altitude pulmonary oedema is a potentially fatal condition that can occur in 1-2% of individuals travelling to altitudes above 3000m. Which of the following physiological responses to altitude is the most likely cause of high-altitude pulmonary oedema?

Hepatic drug clearance is reduced in old age. Which of the following ageing changes is currently believed to have the biggest impact on hepatic drug metabolism?

A boy and his maternal uncle have haemophilia A. Polymerase chain reaction (PCR) analyses of three exons of the gene responsible for haemophilia A, F8C, are shown in the figure below. The analyses included DNA from a normal male (lane 1), the affected boy (lane 2), his affected uncle (lane 3), and the boy’s mother (lane 4). What is the most likely explanation for the presence of a band corresponding to exon 4 in the mother? The mother:

In the general community, which of the following is the major pathogenic factor for reflux oesophagitis?

Drugs A and B have the following properties in healthy individuals: In such healthy individuals, haemodialysis shortens the half-life of drug A much more than it shortens the half-life of drug B. This difference is best explained by which of the following characteristics of drug B?

Old age is associated with diminished pharmacodynamic response to beta adrenergic antagonists (beta blockers). Which of the following mechanisms best explains this?

The diagram below shows the time-course of a typical ventricular myocyte action potential (Figure 1a). Figure 1b shows the principal cation currents between the intra and extra-cellular space concurrent with phase 0-3 of the action potential shown in Figure 1a. The direction and size of the arrows in Figure 1b indicate whether the current is inward-directed or outward-directed and the relative current strengths of the ion identified by a letter at the base of the arrow.

The renal clearance of drugs that are weak bases and weak acids is affected by changes in the urine pH. The most accurate representation of how the pH changes clearance is:

Cholinesterase inhibitors are prescribed for Alzheimer's disease. Which of the following is a typical dose-dependent (type A) adverse drug reaction expected with this group of drugs?

Which of the following is most characteristic of a patient with haemophilia A with 8% baseline factor VIII activity?

Following kidney transplantation, which of the following is the most likely manifestation of BK virus infection?

A patient presents with an anterior non-ST elevation myocardial infarction with transient T-wave inversion in V3-6. There is a typical rise in CK-MB (creatine kinase myocardial tissue) (2 x URL at 12 hr and 5 x URL at 24 hrs) and Troponin T (2 x URL at 12 hr and 20 x URL at 24 hrs). Levels are expressed as a multiple of the upper reference limit (URL). 72 hours after the onset of the first episode, the patient experiences recurrent chest pain. If present, which of the following BEST indicates that the patient has had a recurrent myocardial infarct?

Which of the following is the primary mechanism of body iron regulation?

Resistance of gram-positive organisms to penicillin is most commonly mediated through which of the following mechanisms?

Which of the following findings is most specific for the diagnosis of pernicious anaemia?

Which analgesic is most likely to lead to a serious drug interaction if combined with an MAO (monoamine oxidase) inhibitor (e.g. moclobemide)?