Clin Chem Ch 23-24 – Flashcards
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Scurvy is a disorder caused by a deficiency in which of the following?
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Vitamin C
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Vitamins A, D, and K are classified as:
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Fat-soluble
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Vitamin B12 is also named:
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Cyanocobalamin
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Which disorder is associated with vitamin B1 (thiamin) deficiency?
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Beriberi
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A deficiency of vitamin K (menaquinone) can result in which of the following?
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Increased Clotting Time
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The term associated with indirect methods for assessment of vitamin status is termed:
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Functional Assays
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Retinol is formed from which of the following vitamins?
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Preformed Vitamin A
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Insufficient amounts of vitamin A can lead to degenerative changes to the cornea, which leads to poor dark adaptation, or night blindness, also known as:
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Nyctalopia
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Vitamin D deficiency leads to which of the following conditions?
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Rickets
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Which of the following functions as a chain-breaking antioxidant and is a pyroxyl radical scavenger that protects LDL and polyunsaturated fats in membranes from oxidation?
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α-tocopherol
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Vitamin E toxicity has been associated with which of the following?
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An affliction of premature infants who have been exposed to high oxygen therapy and later developed retinopathy of prematurity (formerly retrolental fibroplasias)
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A direct assay for measurement of plasma phylloquinone is useful to assess:
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Vitamin K status
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Decreased serum levels of vitamin B12 and folic acid are seen in patients with which of the following?
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Sprue
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A patient with megaloblastic anemia would show which of the following?
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↓Vitamin B12 ↓Folic Acid
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An individual who consumes massive amounts of vitamin C may develop kidney stones consisting of:
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Oxalic Acid
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Coenzyme A (CoA) contains which of the following?
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Pantothenic Acid
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Changes in vitamin B12 are most dramatic in tissues with the greatest rate of cell turnover because:
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Deficiencies result in impaired DNA synthesis in any cell where chromosomal replication and division takes place
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Three natural forms of vitamin B6 are:
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Pyridoxine (pyridoxal)(PN), Pyridoxamine (PM), Pyridoxal (PL)
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Measurement of vitamin B12 concentration in serum using an immunoassay is an example of which of the following?
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Direct Assay
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Which of the following is described as a nervous system ailment because of a deficiency of thiamine?
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Beriberi
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Rickets in children or osteoporosis in adults can be minimized though dietary supplementation with which of the following?
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Vitamin D, calcium, and phosphorus
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Pellagra is associated with a deficiency of which of the following vitamins?
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Vitamin B3 (Niacin)
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Niacin is converted to which of the following two cofactors?
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Nicotinamide-adenine dinucleotide and nicotinamide-adenine dinucleotide phosphate
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Which vitamin is a component of two redox coenzymes?
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Vitamin B2 (Ribovlavin)
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In which of the following disorders would the maternal serum level of α1-fetoprotein be elevated?
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Neural tube defect
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Which of the following statement is correct about PSA?
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It is a single-chain glycoprotein, It is used as a tumor marker, It is quantified in serum by immunoassays
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Which of the following biomarkers is elevated in nonmucinous epithelial ovarian cancer?
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CA 125
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Which of the following is a sialylated Lewis blood group antigen associated with colorectal cancer?
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CA 19-9
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Which of the following biomarkers are elevated in advanced stages of breast cancer?
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CA 15-3 and CA 549
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Which tumor marker is associated with cancer of the urinary bladder?
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Nuclear matrix protein
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What is the clinical usefulness of measuring carcinoembryonic antigen?
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Monitoring for recurrence of colon cancer
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Which of the following is used to assess the usefulness of trastuzumab (Herceptin®) therapy for breast cancer?
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HER-2/neu
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Which type of hCG test would be most useful to assess a person suspected of having testicular cancer?
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Plasma immunoassay for intact hCG and the β-hCG subunits
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A markedly elevated serum AFP is associated with which of the following?
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Hepatoma
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Which of the following assays is recommended as a screening test for colorectal cancer in persons over 50 years of age?
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Occult blood t test
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Which of the following must be determined to calculate diagnostic specificity?
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True-negatives and false-positives
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Which statement below best describes the molecular difference between free PSA (fPSA) and complex PSA (cPSA)?
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Free PSA is not bound by compounds such as ACT, PCI, API, or AMG
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The production of alpha fetal protein (AFP) in a healthy individual is best reflected by which of the following statements?
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The production of AFP declines rapidly at birth and healthy adults and children have negligible or undetectable levels in serum
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The combination of squamous cell carcinoma antigen (SCCA) and CYFRA 21-1 test results can be used to provide reliable laboratory data for the differential diagnosis of which disease?
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Non-squamous cell lung carcinoma
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A new test for breast cancer is found to have a sensitivity of 85.0% and a specificity of 90.0%. If the prevalence of breast cancer is 3.5% in women over 45 years old, what is the predictive value of a positive test result (PV+) in this group?
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23.6
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Nuclear matrix protein-22 (NMP) is a tumor marker designed for what purpose?
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Test for recurrence of bladder cancer
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Which molecular form(s) is/are measured by an intact β-hCG assay?
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The whole molecule
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Diagnostic specificity is defined as which of the following?
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The probability that a laboratory test will be negative in the absence of disease
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A patient presents with the following symptoms: •Loss of appetite •Generalized weakness and irritability •Abdominal pain and vomiting •Bright red tongue (glossitis) •Skin rash ("Casal's necklace") Which of the following is associated with these symptoms?
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Pellagra
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A new tumor marker assay for prostate specific antigen (PSA) is evaluated for diagnostic sensitivity by testing serum samples from patients who have been diagnosed as having prostate cancer. The following results were obtained: •Number of prostate cancer patients who tested positive by the new assay = 42 out 46 •Number of patients who did not have cancer and tested negative by the new assay = 31 out of 32 What is the sensitivity of the new assay for PSA?
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91.3%
