🩺 Q458: [Hematology & Hemostasis Case (Series #3, Case #5)] In automated hematology analyzers, the Coulter impedance principle detects cells by measuring:
Anonymous Quiz
0%
A) Light scatter intensity at 90 degrees
92%
B) Electrical resistance change as non-conductive cells pass an aperture
8%
C) Fluorescence emission after nucleic acid staining
0%
D) Radiofrequency conductivity absorption
🩺 Q459: In a competitive immunoassay, what is the relationship between the concentration of the analyte in the patient sample and the measured signal?
Anonymous Quiz
8%
A) Directly proportional
46%
B) Inversely proportional
31%
C) Exponentially proportional
15%
D) Logarithmically proportional
🩺 Q460: A Levey-Jennings chart shows a 'trend' in QC results over the last 6 days, where values are progressively increasing. What is the most likely cause?
Anonymous Quiz
15%
A) Random error
46%
B) Deterioration of reagents or light source
38%
C) Sudden change in the calibration setting
0%
D) Operator error in pipetting
🩺 Q460: [Clinical Biochemistry Case (Series #2, Case #3)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
31%
A) Creatine Kinase-MB (CK-MB)
0%
B) Myoglobin
62%
Cardiac Troponin I (cTnI)
8%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q462: What is the primary purpose of a Safety Data Sheet (SDS) in the laboratory?
Anonymous Quiz
0%
A) To provide instructions on test methodology
8%
B) To document employee training hours
92%
C) To communicate information regarding chemical hazards and handling precautions
0%
D) To list the inventory of laboratory supplies
🩺 Q462: [Clinical Biochemistry Case (Series #2, Case #4)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
46%
A) Decreased pH, decreased HCO3-, and normal PaCO2
54%
B) Decreased pH, increased PaCO2, and normal HCO3-
0%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q464: What is the purpose of 'blind' proficiency testing samples in a clinical laboratory?
Anonymous Quiz
0%
A) To test the proficiency of the instrument only
100%
B) To ensure that samples are treated exactly like patient samples, preventing bias
0%
C) To reduce the cost of quality assurance
0%
D) To compare results between different hospitals
🩺 Q464: [Clinical Biochemistry Case (Series #3, Case #5)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
38%
A) Creatine Kinase-MB (CK-MB)
8%
B) Myoglobin
46%
Cardiac Troponin I (cTnI)
8%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q466: A method has high precision but low accuracy. How is this best described?
Anonymous Quiz
0%
A) The results are close to the true value but show wide scatter
83%
B) The results are clustered tightly together but are far from the true value
0%
C) The results are scattered and far from the true value
17%
D) The results are tightly clustered and close to the true value
🩺 Q466: [Clinical Biochemistry Case (Series #3, Case #6)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
62%
A) Decreased pH, decreased HCO3-, and normal PaCO2
23%
B) Decreased pH, increased PaCO2, and normal HCO3-
15%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q467: When handling concentrated acids or bases, which safety practice is mandatory?
Anonymous Quiz
8%
Add water to the acid to dilute
33%
B) Add the acid to the water slowly
58%
C) Use a standard fume hood without airflow monitoring
0%
D) Store acids and bases in the same cabinet
🩺 Q469: [Clinical Biochemistry Case (Series #4, Case #7)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
33%
A) Creatine Kinase-MB (CK-MB)
8%
B) Myoglobin
58%
Cardiac Troponin I (cTnI)
0%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q470: [Clinical Biochemistry Case (Series #4, Case #8)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
58%
A) Decreased pH, decreased HCO3-, and normal PaCO2
17%
B) Decreased pH, increased PaCO2, and normal HCO3-
25%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q471: [Clinical Biochemistry Case (Series #5, Case #9)] Which cardiac biomarker demonstrates the highest myocardial specificity and remains elevated up to 10-14 days following acute MI?
Anonymous Quiz
31%
A) Creatine Kinase-MB (CK-MB)
0%
B) Myoglobin
69%
Cardiac Troponin I (cTnI)
0%
D) Lactate Dehydrogenase (LDH-1)
🩺 Q472: [Clinical Biochemistry Case (Series #5, Case #10)] In arterial blood gas analysis, an uncompensated metabolic acidosis is typically characterized by:
Anonymous Quiz
50%
A) Decreased pH, decreased HCO3-, and normal PaCO2
25%
B) Decreased pH, increased PaCO2, and normal HCO3-
25%
C) Increased pH, decreased PaCO2, and increased HCO3-
0%
D) Normal pH, normal PaCO2, and decreased HCO3-
🩺 Q473: A patient presents with a persistent, non-healing foot ulcer. A tissue biopsy is sent for culture. After 48 hours of incubation on blood agar, small, non-hemolytic colonies are observed. The organism is catalase-negative, bile esculin-positive, and grows in 6.5% NaCl. Which of the following
Anonymous Quiz
31%
A) Streptococcus pyogenes
38%
B) Enterococcus faecalis
15%
C) Staphylococcus aureus
15%
D) Streptococcus agalactiae
🩺 Q474: A skin scraping from a patient with tinea pedis is examined using 10% KOH. Microscopy reveals septate hyphae and arthroconidia. Which laboratory test would best differentiate Trichophyton rubrum from Trichophyton mentagrophytes?
Anonymous Quiz
15%
A) Urease test
46%
B) Germ tube test
31%
C) Oxidase test
8%
D) Catalase test
🩺 Q475: A stool sample from a traveler returning from Southeast Asia reveals a large, barrel-shaped egg with bipolar plugs. Which parasite is the most likely causative agent?
Anonymous Quiz
17%
Ascaris lumbricoides
50%
B) Trichuris trichiura
33%
C) Enterobius vermicularis
0%
D) Hookworm
🩺 Q476: A patient is suspected of having an acute Epstein-Barr virus (EBV) infection. Which of the following serological patterns would support an acute primary infection?
Anonymous Quiz
23%
A) VCA IgM positive, EBNA negative
77%
B) VCA IgG positive, EBNA positive
0%
C) VCA IgM negative, EBNA positive
0%
D) VCA IgG negative, EBNA negative
🩺 Q477: A sputum sample shows gram-negative diplococci that are oxidase-positive and produce DNase. The organism grows on nutrient agar at room temperature. What is the most likely identity?
Anonymous Quiz
27%
A) Neisseria gonorrhoeae
47%
B) Neisseria meningitidis
13%
C) Moraxella catarrhalis
13%
D) Haemophilus influenzae