CLINICAL CHEMISTRY HARR

100問 • 1年前

問題一覧

Which of the following processes is part of the normal metabolism of bilirubin? A. Both conjugated and unconjugated bilirubin are excreted into the bile B. Methene bridges of bilirubin are reduced by intestinal bacteria forming urobilinogens C. Most of the bilirubin delivered into the intestine is reabsorbed D. Bilirubin and urobilinogen reabsorbed from the intestine are mainly excreted by the kidneys

B. Methene bridges of bilirubin are reduced by intestinal bacteria forming urobilinogens

Which of the following is a characteristic of conjugated bilirubin? A. It is water soluble B. It reacts more slowly than unconjugated bilirubin C. It is more stable than unconjugated bilirubin D. It has the same absorbance properties as unconjugated bilirubin

A. It is water soluble

Which of the following statements regarding urobilinogen is true? A. It is formed in the intestines by bacterial reduction of bilirubin B. It consists of a single water-soluble bile pigment C. It is measured by its reaction with p-aminosalicylate D. In hemolytic anemia, it is decreased in urine and feces

A. It is formed in the intestines by bacterial reduction of bilirubin

Which statement regarding bilirubin metabolism is true? A. Bilirubin undergoes rapid photo-oxidation when exposed to daylight B. Bilirubin excretion is inhibited by barbiturates C. Bilirubin excretion is increased by chlorpromazine D. Bilirubin is excreted only as the diglucuronide

A. Bilirubin undergoes rapid photo-oxidation when exposed to daylight

Which condition is caused by deficient secretion of bilirubin into the bile canaliculi? A. Gilbert’s disease B. Neonatal hyperbilirubinemia C. Dubin–Johnson syndrome D. Crigler–Najjar syndrome

C. Dubin–Johnson syndrome

In hepatitis, the rise in serum conjugated bilirubin can be caused by: A. Secondary renal insufficiency B. Failure of the enterohepatic circulation C. Enzymatic conversion of urobilinogen to bilirubin D. Extrahepatic conjugation

B. Failure of the enterohepatic circulation

Which of the following is a characteristic of obstructive jaundice? A. The ratio of direct to total bilirubin is greater than 1:2 B. Conjugated bilirubin is elevated, but unconjugated bilirubin is normal C. Urinary urobilinogen is increased D. Urinary bilirubin is normal

A. The ratio of direct to total bilirubin is greater than 1:2

Which of the following would cause an increase in only the unconjugated bilirubin? A. Hemolytic anemia B. Obstructive jaundice C. Hepatitis D. Hepatic cirrhosis

A. Hemolytic anemia

Which form of hyperbilirubinemia is caused by an inherited absence of UDP-glucuronyl transferase? A. Gilbert’s syndrome B. Rotor syndrome C. Crigler–Najjar syndrome D. Dubin–Johnson syndrome

C. Crigler–Najjar syndrome

Which statement regarding total and direct bilirubin levels is true? A. Total bilirubin level is a less sensitive and specific marker of liver disease than the direct level B. Direct bilirubin exceeds 3.5 mg/dL in most cases of hemolytic anemia C. Direct bilirubin is normal in cholestatic liver disease D. The ratio of direct to total bilirubin exceeds 0.40 in hemolytic anemia

A. Total bilirubin level is a less sensitive and specific marker of liver disease than the direct level

Which statement best characterizes serum bilirubin levels in the first week following delivery? A. Serum bilirubin 24 hours after delivery should not exceed the upper reference limit for adults B. Jaundice is usually first seen 48–72 hours postpartum in neonatal hyperbilirubinemia C. Serum bilirubin above 5.0 mg/dL occurring 2–5 days after delivery indicates hemolytic or hepatic disease D. Conjugated bilirubin accounts for about 50% of the total bilirubin in neonates

B. Jaundice is usually first seen 48–72 hours postpartum in neonatal hyperbilirubinemia

Which form of jaundice occurs within days of delivery and usually lasts 1–3 weeks, but is not due to normal neonatal hyperbilirubinemia or hemolytic disease of the newborn? A. Gilbert syndrome B. Lucey –Driscoll syndrome C. Rotor syndrome D. Dubin–Johnson syndrome

B. Lucey –Driscoll syndrome

A lab measures total bilirubin by the Jendrassik–Grof bilirubin method with sample blanking. What would be the effect of moderate hemolysis on the test result? A. Falsely increased due to optical interference B. Falsely increased due to release of bilirubin from RBCs C. Falsely low due to inhibition of the diazo reaction by hemoglobin D. No effect due to correction of positive interference by sample blanking

C. Falsely low due to inhibition of the diazo reaction by hemoglobin

Which reagent is used in the Jendrassik–Grof method to solubilize unconjugated bilirubin? A. 50% methanol B. N-butanol C. Caffeine D. Acetic acid

C. Caffeine

Which statement about colorimetric bilirubin methods is true? A. Direct bilirubin must react with diazo reagent under alkaline conditions B. Most methods are based upon reaction with diazotized sulfanilic acid C. Ascorbic acid can be used to eliminate interference caused by Hgb D. The color of the azobilirubin product is independent of pH

B. Most methods are based upon reaction with diazotized sulfanilic acid

Which statement regarding the measurement of bilirubin by the Jendrassik–Grof method is correct? A. The same diluent is used for both total and direct assays to minimize differences in reactivity B. Positive interference by Hgb is prevented by the addition of HCl after the diazo reaction C. The color of the azobilirubin product is intensified by the addition of ascorbic acid D. Fehling’s reagent is added after the diazo reaction to reduce optical interference by hemoglobin

D. Fehling’s reagent is added after the diazo reaction to reduce optical interference by hemoglobin

A neonatal bilirubin assay performed at the nursery by bichromatic direct spectrophotometry is 4.0 mg/dL. Four hours later, a second sample assayed for total bilirubin by the Jendrassik–Grof method gives a result of 3.0 mg/dL. Both samples are reported to be hemolyzed. What is the most likely explanation of these results? A. Hgb interference in the second assay B. d-Bilirubin contributing to the result of the first assay C. Falsely high results from the first assay caused by direct bilirubin D. Physiological variation owing to premature hepatic microsomal enzymes

A. Hgb interference in the second assay

In the enzymatic assay of bilirubin, how is measurement of both total and direct bilirubin accomplished? A. Using different pH for total and direct assays B. Using UDP glucuronyl transferase and bilirubin reductase C. Using different polarity modifiers D. Measuring the rate of absorbance decrease at different time intervals

A. Using different pH for total and direct assays

What is the principle of the transcutaneous bilirubin assay? A. Conductivity B. Amperometric inhibition C. Multiwavelength reflectance photometry D. Infrared spectroscopy

C. Multiwavelength reflectance photometry

How many grams of sodium hydroxide (NaOH) are required to prepare 150.0 mL of a 5.0% w/v solution? A. 1.5 g B. 4.0 g C. 7.5 g D. 15.0 g

C. 7.5 g

How many milliliters of glacial acetic acid are needed to prepare 2.0 L of 10.0% v/v acetic acid? A. 10.0 mL B. 20.0 mL C. 100.0 mL D. 200.0 mL

D. 200.0 mL

A biuret reagent requires preparation of a stock solution containing 9.6 g of copper II sulfate (CuSO4) per liter. How many grams of CuSO4 • 5H2O are needed to prepare 1.0 L of the stock solution? Atomic weights: H = 1.0; Cu = 63.6; O = 16.0; S = 32.1 A. 5.4 g B. 6.1 g C. 15.0 g D. 17.0 g

C. 15.0 g

How many milliliters of HNO3 (purity 68.0%, specific gravity 1.42) are needed to prepare 1.0 L of a 2.0 N solution? Atomic weights: H = 1.0; N = 14.0; O = 16.0 A. 89.5 mL B. 126.0 mL C. 130.5 mL D. 180.0 mL

C. 130.5 mL

Convert 10.0 mg/dL calcium (atomic weight = 40.1) to International System of Units (SI). A. 0.25 B. 0.40 C. 2.5 D. 0.4

C. 2.5

Convert 2.0 mEq/L magnesium (atomic weight = 24.3) to milligrams per deciliter. A. 0.8 mg/dL B. 1.2 mg/dL C. 2.4 mg/dL D. 4.9 mg/dL

C. 2.4 mg/dL

How many milliliters of a 2,000.0 mg/dL glucose stock solution are needed to prepare 100.0 mL of a 150.0 mg/dL glucose working standard? A. 1.5 mL B. 7.5 mL C. 15.0 mL D. 25.0 mL

B. 7.5 mL

What is the pH of a solution of HNO3, if the hydrogen ion concentration is 2.5 × 10–2 M? A. 1.0 B. 1.6 C. 2.5 D. 2.8

B. 1.6

Calculate the pH of a solution of 1.5 × 10–5 M NH4OH. A. 4.2 B. 7.2 C. 9.2 D. 11.2

C. 9.2

How many significant figures should be reported when the pH of a 0.060 M solution of nitric acid is calculated? A. 1 B. 2 C. 3 D. 4

B. 2

What is the pH of a 0.05 M solution of acetic acid? Ka = 1.75 × 10–5, pKa = 4.76 A. 1.7 B. 3.0 C. 4.3 D. 4.6

B. 3.0

What is the pH of a buffer containing 40.0 mmol/L NaHC2O4 and 4.0 mmol/L H2C2O4? (pKa = 1.25) A. 1.35 B. 2.25 C. 5.75 D. 6.12

B. 2.25

A solvent needed for HPLC requires a 20.0 mmol/L phosphoric acid buffer, pH 3.50, made by mixing KH2PO4 and H3PO4. How many grams of KH2PO4 are required to make 1.0 L of this buffer? Formula weights: KH2PO4 = 136.1; H3PO4 = 98.0; pKa H3PO4 = 2.12 A. 1.96 g B. 2.61 g C. 2.72 g D. 19.2 g

B. 2.61 g

A procedure for cholesterol is calibrated with a serum-based cholesterol standard that was determined by the Abell–Kendall method to be 200.0 mg/dL. Assuming the same volume of sample and reagent are used, calculate the cholesterol concentration in the patient’s sample from the following results. Standard Absorbance Absorbance Concen- of Reagent Absorbance of Patient tration Blank of Standard Serum 200 mg/dL 0.00 0.860 0.740 A. 123 mg/dL B. 172 mg/dL C. 232 mg/dL D. 314 mg/dL

B. 172 mg/dL

A glycerol kinase method for triglyceride calls for a serum blank in which normal saline is substituted for lipase in order to measure endogenous glycerol. Given the following results, and assuming the same volume of sample and reagent are used for each test, calculate the triglyceride concentration in the patient’s sample. A. 119 mg/dL B. 131 mg/dL C. 156 mg/dL D. 180 mg/dL

B. 131 mg/dL

A procedure for aspartate aminotransferase (AST) is performed manually because of a repeating error code for nonlinearity obtained on the laboratory’s automated chemistry analyzer; 0.05 mL of serum and 1.0 mL of substrate are used. The reaction rate is measured at 30°C at 340 nm using a 1.0 cM light path, and the delta absorbance (-?A) per minute is determined to be 0.382. Based upon a molar absorptivity coefficient for NADH at 340 nm of 6.22 X 103 M–1 cM–1 L–1, calculate the enzyme activity in international units (IUs) per liter. A. 26 IU/L B. 326 IU/L C. 1228 IU/L D. 1290 IU/L

D. 1290 IU/L

When referring to quality control (QC) results, what parameter usually determines the acceptable range? A. The 95% confidence interval for the mean B. The range that includes 50% of the results C. The central 68% of results D. The range encompassed by ±2.5 standard deviations

A. The 95% confidence interval for the mean

Which of the following quality control (QC) rules would be broken 1 out of 20 times by chance alone? A. 12s B. 22s C. 13s D. 14s

A. 12s

Which of the following conditions is cause for rejecting an analytical run? A. Two consecutive controls greater than 2 s above or below the mean B. Three consecutive controls greater than 1 s above the mean C. Four controls steadily increasing in value but less than ±1 s from the mean D. One control above +1 s and the other below –1 s from the mean

A. Two consecutive controls greater than 2 s above or below the mean

One of two controls within a run is above +2s and the other control is below –2s from the mean. What do these results indicate? A. Poor precision has led to random error (RE) B. A systematic error (SE) is present C. Proportional error is present D. QC material is contaminated

A. Poor precision has led to random error (RE)

Two consecutive controls are both beyond –2s from the mean. How frequently would this occur on the basis of chance alone? A. 1:100 B. 5:100 C. 1:400 D. 1:1,600

D. 1:1,600

The term R4S means that: A. Four consecutive controls are greater than ±1 standard deviation from the mean B. Two controls in the same run are greater than 4s units apart C. Two consecutive controls in the same run are each greater than ±4s from the mean D. There is a shift above the mean for four consecutive controls

B. Two controls in the same run are greater than 4s units apart

A trend in QC results is most likely caused by: A. Deterioration of the reagent B. Miscalibration of the instrument C. Improper dilution of standards D. Electronic noise

A. Deterioration of the reagent

In most circumstances, when two controls within a run are both greater than ±2s from the mean, what action should be taken first? A. Recalibrate, then repeat controls followed by selected patient samples if quality control is acceptable B. Repeat the controls before taking any corrective action C. Change the reagent lot, then recalibrate D. Prepare fresh standards and recalibrate

A. Recalibrate, then repeat controls followed by selected patient samples if quality control is acceptable

When establishing QC limits, which of the following practices is inappropriate? A. Using last month’s QC data to determine current target limits B. Exclusion of any QC results greater than ±2s from the mean C. Using control results from all shifts on which the assay is performed D. Using limits determined by reference laboratories using the same method

B. Exclusion of any QC results greater than ±2s from the mean

Which of the following assays has the poorest precision

Given the following data, calculate the coefficient of variation for glucose. Analyte Mean Standard Deviation Glucose 76 mg/dL 2.3 A. 3.0% B. 4.6% C. 7.6% D. 33.0%

A. 3.0%

Which of the following plots is best for detecting all types of QC errors? A. Levy–Jennings B. Tonks–Youden C. Cusum D. Linear regression

A. Levy–Jennings

Which of the following plots is best for comparison of precision and accuracy among laboratories? A. Levy–Jennings B. Tonks–Youden C. Cusum D. Linear regression

B. Tonks–Youden

Which plot will give the earliest indication of a shift or trend? A. Levy–Jennings B. Tonks–Youden C. Cusum D. Histogram

C. Cusum

All of the following are requirements for a QC material except: A. Long-term stability B. The matrix is similar to the specimens being tested C. The concentration of analytes reflects the clinical range D. Analyte concentration must be independent of the method of assay

D. Analyte concentration must be independent of the method of assay

Examine the Levy–Jennings chart at the bottom of the previous page and identify the QC problem that occurred during the first half of the month. A. Shift B. Trend C. Random error D. Kurtosis

B. Trend

Referring to the Levy–Jennings chart, what is the first day in the month when the run should be rejected and patient results should be repeated? A. Day 6 B. Day 7 C. Day 8 D. Day 9

C. Day 8

Referring to the Levy–Jennings chart, what analytical error is present during the second half of the month? A. Shift B. Trend C. Random error D. Kurtosis

A. Shift

What is the first day in the second half of the month that patient results would be rejected? A. Day 16 B. Day 17 C. Day 18 D. Day 19

B. Day 17

Given the following QC chart, identify the day in which a violation of the R4s QC rule occurs. A. Day 3 B. Day 8 C. Day 10 D. Day 15

D. Day 15

What is the minimum requirement for performing QC for a total protein assay? A. One level assayed every 8 hours B. Two levels assayed within 8 hours C. Two levels assayed within 24 hours D. Three levels assayed within 24 hours

C. Two levels assayed within 24 hours

Which of the following statistical tests is used to compare the means of two methods? A. Student’s t test B. F distribution C. Correlation coefficient (r) D. Linear regression analysis

A. Student’s t test

Two freezing point osmometers are compared by running 40 paired patient samples one time on each instrument, and the following results are obtained: If the critical value for F = 2.8, then what conclusion can be drawn regarding the precision of the two instruments? A. There is no statistically significant difference in precision B. Osmometer A demonstrates better precision that is statistically significant C. Osmometer B demonstrates better precision that is statistically significant D. Precision cannot be evaluated statistically when single measurements are made on samples

D. 11.0

When the magnitude of error increases with increasing sample concentration, it is called: A. Constant error B. Proportional error C. Random error D. Bias

B. Proportional error

Which explanation is the best interpretation of the following BUN bias plot? A. The new method consistently overestimates the BUN by a constant concentration B. The new method is greater than the reference method but not by a statistically significant margin C. The new method is lower than the reference method by 5 mg/dL D. The new method is lower than the reference and the magnitude is concentration dependent

D. The new method is lower than the reference and the magnitude is concentration dependent

Serum samples collected from hospitalized patients over a 2-week period are split into two aliquots and analyzed for prostate specific antigen (PSA) by two methods. Each sample was assayed by both methods within 30 minutes of collection by a technologist familiar with both methods. The reference method is method × (upper reference limit = 4.0 μg/L). Linear regression analysis was performed by t Linear Correlation Standard Error of Regression Coefficient (r) Estimate (sy/x) ŷ = 2.10 + 1.01x 0.984 0.23 Which statement best characterizes the relationship between the methods? A. There is a significant bias caused by constant error B. There is a significant proportional error C. There is no disagreement between the methods because the correlation coefficient approaches 1.0 D. There is no systematic error, but the random error of the new method is unacceptable

A. There is a significant bias caused by constant error

Which statement best summarizes the relationship between the new BUN method and reference method based upon the following linear regression scatterplot? A. The methods agree very well but show a high standard error of estimate B. There is little or no constant error, but some proportional error C. There will be a significant degree of uncertainty in the regression equation D. There is significant constant and proportional error but little random error

B. There is little or no constant error, but some proportional error

A new method for BUN is evaluated by comparing the results of 40 paired patient samples to the urease-UV method. Normal and high controls were run on each shift for 5 days, five times per day. The results are as follows: Linear Regression Low Control High Control y = –0.3 + 0.90x –x = 14.2 mg/dL; – x = 48.6 mg/dL; s = 1.24 s = 1.12 What is the total analytical error estimate for a sample having a concentration of 50 mg/dL? A. –2.2 mg/dL B. –2.8 mg/dL C. –7.5 mg/dL D. –10.0 mg/dL

C. –7.5 mg/dL

In addition to the number of true negatives (TN), which of the following measurements is needed to calculate specificity? A. True positives B. Prevalence C. False negatives D. False positives

D. False positives

A new tumor marker for ovarian cancer is evaluated for sensitivity by testing serum samples from patients who have been diagnosed by staging biopsy as having malignant or benign lesions. The following results were obtained: Number of malignant patients who are positive for CA 125 = 21 out of 24 Number of benign patients who are negative for CA 125 = 61 out of 62 What is the sensitivity of the new CA 125 test? A. 98.4% B. 95.3% C. 87.5% D. 85.0%

C. 87.5%

A new test for prostate cancer is found to have a sensitivity of 80.0% and a specificity of 84.0%. If the prevalence of prostate cancer is 4.0% in men over 42 years old, what is the predictive value of a positive test result (PV+) in this group? A. 96.0% B. 86.0% C. 32.4% D. 17.2%

D. 17.2%

What measurement in addition to true negatives and prevalence is required to calculate the predictive value of a negative test result (PV–)? A. False negatives B. Variance C. True positives D. False positives

A. False negatives

A laboratory is establishing a reference range for a new analyte and wants the range to be determined by the regional population of adults age 18 and older. The analyte concentration is known to be independent of race and gender. Which is the most appropriate process to follow? A. Determine the mean and standard deviation of the analyte from 40 healthy adults and calculate the ±2s limit B. Measure the analyte in 120 healthy adults and calculate the central 95th percentile C. Measure the analyte in 120 healthy adults and use the lowest and highest as the reference range limits D. Measure the analyte in 60 healthy adults and 60 adults with conditions that affect the analyte concentration; calculate the concentration of least overlap

B. Measure the analyte in 120 healthy adults and calculate the central 95th percentile

When comparing the laboratory’s monthly mean to its peer group to determine if bias is present, what statistic is most appropriate? A. F test B. Linear regression analysis C. Correlation coefficient D. Standard deviation index

D. Standard deviation index

Which of the following methods is most useful in order to detect sample misidentification? A. Cumulative summation B. Critical limit C. Delta limit D. Significant change limit

C. Delta limit

Which of the following total quality management tools can be used to calculate the analytical error rate for an analyte in the clinical laboratory? A. LEAN B. Six sigma C. ISO 9000 D. Laboratory information system

B. Six sigma

In which circumstances is a validation study (versus performing routine quality control) required? A. Instrument recalibration B. Source lamp or ion selective electrode change C. Change in reagent lot D. Change in calibrator lot

C. Change in reagent lot

The following plot represents a study of a screening test for malignant prostate cancer using plasma PSA (ng/mL). The outcome measured was positive cytology results obtained by biopsy. What concentration gives the highest sensitivity A. 2.6 B. 3.6 C. 3.8 D. 5.2

B. 3.6

Creatinine is formed from the: A. Oxidation of creatine B. Oxidation of protein C. Deamination of dibasic amino acids D. Metabolism of purines

A. Oxidation of creatine

Creatinine is considered the substance of choice to measure endogenous renal clearance because: A. The rate of formation per day is independent of body size B. It is completely filtered by the glomeruli C. Plasma levels are highly dependent upon diet D. Clearance is the same for both men and women

B. It is completely filtered by the glomeruli

Which statement regarding creatinine is true? A. Serum levels are elevated in early renal disease B. High serum levels result from reduced glomerular filtration C. Serum creatine has the same diagnostic utility as serum creatinine D. Serum creatinine is a more sensitive measure of renal function than creatinine clearanc

B. High serum levels result from reduced glomerular filtration

Which of the following formulas is the correct expression for creatinine clearance? A. Creatinine clearance = U/P X V X 1.73/A B. Creatinine clearance = P/V X U X A/1.73 C. Creatinine clearance = P/V X U X 1.73/A D. Creatinine clearance = U/V X P X 1.73/A

A. Creatinine clearance = U/P X V X 1.73/A

Which of the following conditions is most likely to cause a falsely high creatinine clearance result? A. The patient uses the midstream void procedure when collecting his or her urine B. The patient adds tap water to the urine container because he or she forgets to save one of the urine samples C. The patient does not empty his or her bladder at the conclusion of the test D. The patient empties his or her bladder at the start of the test and adds the urine to the collection

D. The patient empties his or her bladder at the start of the test and adds the urine to the collection

The modification of diet in renal disease (MDRD) formula for calculating eGFR requires which four parameters? A. Urine creatinine, serum creatinine, height, weight B. Serum creatinine, age, gender, race C. Serum creatinine, height, weight, age D. Urine creatinine, gender, weight, age

B. Serum creatinine, age, gender, race

What substance may be measured as an alternative to creatinine for evaluating GFR? A. Plasma urea B. Cystatin C C. Uric acid D. Potassium

B. Cystatin C

Which of the following enzymes allows creatinine to be measured by coupling the creatinine amidohydrolase (creatininase) reaction to the peroxidase reaction? A. Glucose-6-phosphate dehydrogenase B. Creatinine iminohydrolase C. Sarcosine oxidase D. Creatine kinase

C. Sarcosine oxidase

Select the primary reagent used in the Jaffe method for creatinine. A. Alkaline copper II sulfate B. Saturated picric acid and NaOH C. Sodium nitroprusside and phenol D. Phosphotungstic acid

B. Saturated picric acid and NaOH

Select the primary reagent used in the Jaffe method for creatinine. A. Alkaline copper II sulfate B. Saturated picric acid and NaOH C. Sodium nitroprusside and phenol D. Phosphotungstic acid

B. Saturated picric acid and NaOH

Interference from other reducing substances can be partially eliminated in the Jaffe reaction by: A. Measuring the product at 340 nm B. Measuring the product with an electrode C. Measuring the timed rate of product formation D. Performing a sample blank

C. Measuring the timed rate of product formation

Which of the following statements is true? A. Cystatin C is measured immunochemically B. The calibrator used for cystatin C is traceable to the National Bureau of Standards calibrator C. Cystatin C assays have a lower coefficient of variation than plasma creatinine D. Enzymatic and rate Jaffe reactions for creatinine give comparable results

A. Cystatin C is measured immunochemically

In which case would eGFR derived from the plasma creatinine likely give a more accurate measure of GFR than measurement of plasma cystatin C? A. Diabetic patient B. Chronic renal failure C. Post–renal transplant D. Chronic hepatitis

C. Post–renal transplant

A sample of amniotic fluid collected for fetal lung maturity studies from a woman with a pregnancy compromised by hemolytic disease of the newborn (HDN) has a creatinine of 88 mg/dL. What is the most likely cause of this result? A. The specimen is contaminated with blood B. Bilirubin has interfered with the measurement of creatinine C. A random error occurred when the absorbance signal was being processed by the analyzer D. The fluid is urine from accidental puncture of the urinary bladder

D. The fluid is urine from accidental puncture of the urinary bladder

Which analyte should be reported as a ratio using creatinine concentration as a reference? A. Urinary microalbumin B. Urinary estriol C. Urinary sodium D. Urinary urea

A. Urinary microalbumin

Urea is produced from: A. The catabolism of proteins and amino acids B. Oxidation of purines C. Oxidation of pyrimidines D. The breakdown of complex carbohydrates

A. The catabolism of proteins and amino acids

Urea concentration is calculated from the BUN by multiplying by a factor of: A. 0.5 B. 2.14 C. 6.45 D. 14

B. 2.14

Which of the statements below about serum urea is true? A. Levels are independent of diet B. Urea is not reabsorbed by the renal tubules C. High BUN levels can result from necrotic liver disease D. BUN is elevated in prerenal as well as renal failure

D. BUN is elevated in prerenal as well as renal failure

A patient’s BUN is 60 mg/dL and serum creatinine is 3.0 mg/dL. These results suggest: A. Laboratory error measuring BUN B. Renal failure C. Prerenal failure D. Patient was not fasting

C. Prerenal failure

Urinary urea measurements may be used for calculation of: A. Glomerular filtration B. Renal blood flow C. Nitrogen balance D. All of these options

C. Nitrogen balance

BUN is determined electrochemically by coupling the urease reaction to measurement of: A. Potential with a urea-selective electrode B. The timed rate of increase in conductivity C. The oxidation of ammonia D. Carbon dioxide

B. The timed rate of increase in conductivity

In the ultraviolet enzymatic method for BUN, the urease reaction is coupled to a second enzymatic reaction using: A. AST B. Glutamate dehydrogenase C. Glutamine synthetase D. Alanine aminotransferase (ALT)

B. Glutamate dehydrogenase

Which product is measured in the coupling step of the urease-UV method for BUN? A. CO2 B. Dinitrophenylhydrazine C. Diphenylcarbazone D. NAD+

D. NAD+

Which enzyme deficiency is responsible for phenylketonuria (PKU)? A. Phenylalanine hydroxylase B. Tyrosine transaminase C. p-Hydroxyphenylpyruvic acid oxidase D. Homogentisic acid oxidase

A. Phenylalanine hydroxylase

Which of the following conditions is classified as a renal-type aminoaciduria? A. Fanconi syndrome B. Wilson’s disease C. Hepatitis D. Homocystinuria

A. Fanconi syndrome

Which aminoaciduria results in the overflow of branched chain amino acids? A. Hartnup’s disease B. Alkaptonuria C. Homocystinuria D. Maple syrup urine disease

D. Maple syrup urine disease

100

In addition to phenylketonuria, maple syrup urine disease, and homocystinuria, what other aminoaciduria can be detected by tandem MS? A. Alkaptonuria B. Hartnup disease C. Citrullinemia D. Cystinuria

C. Citrullinemia

other names parasitology

Yves Laure Pimentel · 70問 · 2年前

other names parasitology