Studied by 52 peoplePatinet with suspected primary hyperthyridism associated with Graves' disease, one would expect the following lab serum results: T4___, TSH _____
Normal, increased Increased, increased Decreased, normal Increased, decreased Increased, normal
increased, decreased
Major fraction of organic iodine circulating in the blood is triiodothyronine diiodotyrosine tetraiodothyronine thyroglobulin
tetraiodothyronine
During pregnancy, serum TBG concentration ..........., total thyroid hormone levels are ..........., and free thyroid hormone levels are ........... a. is unaffected, increased, increased b. decreases, decreases, unaffected c. is unaffected, decreased, decreased d. increases, increased, unaffected
d. increases, increased, unaffected
Which one of the following statements about T3 is FALSE? a.It may be elevated to a greater extent than T4 in hyperthyroidism. b. It is commonly decreased in patients with nonthyroidal illness. c. It is thought to be the most active thyroid hormone. d. It is not bound to serum proteins.
d. It is not bound to serum proteins.
The old T3 resin uptake test has been replaced by a direct assay for: a. thyroglobulin b. binding capacity of thyroxine-binding globulin c. circulating free t3 d. thyroxine-binding globuline e. bound t3
bound t3
A two-year-old child with a decreased serum T4 is described as being somewhat dwarfed, stocky, and overweight and having coarse features. Of the following, the most informative additional laboratory test would be serum: a. TSH b. T3 c. cholesterol
TSH
What tests are used as part of newborn screening programs to identify congenital hypothyroidism? a. t3 and/or tsh b. t4 and or tsh c. t3 and/t4
b. t4 and.or tsh
The TRH (thyrotropin releasing hormone) stimulation test is useful in differentiating hypothalamic hypothyroidism from: a. pituitary hypothyroidism b. primary hypothyroidism c. hashimoto's thyroiditis
a. pituitary hypothyroidism
True or false? When taken by a euthyroid individual, oral contraceptives will have an increasing effect on thyroxine binding globulin.
true
True or false? Individuals taking recurring regimens of androgens or anabolic steroid drugs may exhibit increased TBG levels.
false
The primary physiological regulator of parathyroid hormone (PTH) synthesis and secretion is: a. pth stimulating hormone b. concentration of pth in blood c. concentration of free calcium in blood or extracellular fluid
c. concentration of free calcium in blood or extracellular fluid
Hypoparathyroidism is most commonly caused by: a. parathyroid glad destruction b. resistance to parathyroid hormone c. adenoma of the parathyroid gland
a. parathyroid glad destruction
What makes up the organic matrix component of bone? a. cells only b. calcium protein and collegen c. minerals and cells only
b. calcium protein and collagen
In bone a. calcium is complexed with bicarbonate b. osteoblasts are the bone forming cells c. collagen component is type 2 collagen
osteoblasts
An individual’s serum phosphate level is decreased but his physician cannot determine a physiological basis for this abnormal result. What could possibly have caused this result? a. specimen hemolysis b. diurnal variation c. use of IV carbohydrate therapy to stimulate insulin secretion
c. use of IV carbohydrate therapy to stimulate insulin secretion
Hypercalcemia occurs in humoral hypercalcemia of malignancy (HHM) because: a. pth-related protein (PTHrP) is synthesized by tumors and stimulates bone resorption b. osteoclasts bind tumor marker proteins and the process of bone remodeling becomes unregulated c. metastasizing cells synthesize calcium and release it into circulation
a. pth-related protein (PTHrP) is synthesized by tumors and stimulates bone resorption
The clinical usefulness of calcitonin measurement is: a. as a tumor marker for medullary thyroid carcinoma b. in the determination of sources of vitamin d deficiency c. in the assessment of primary hyperparathyroidism
a. as a tumor marker for medullary thyroid carcinoma
Which one of the following diseases is characterized by a loss in bone mass? a. rickets b. osteoporosis c. osteomalacia
osteoporosis
Which one of the following analytes is most useful in distinguishing primary from secondary hyperparathyroidism? a. parathyroid hormone b. vitamin d c. serum calcium
vitamin d
A factor that would alter protein binding of calcium and its redistribution among the three plasma pools would be: a. an altered anion gap b. a change in an individual's posture c. liver disease
liver disease
What causes the total thyroxine (T4) levels to be increased in pregnant women? a. change in thyroglobulin synthesis b. altered glucose metabolism c. hcg-induced thyrotoxicosis
hcg induced thyrotoxicosis
Which one of the following is not a function of the thyroid hormones? a. removal of defective rbcs b. control of metabolic rate c. stimulation of neural development d. increasing cholesterol synthesis and breakdown
a. removal of defective rbcs
Another term used to describe hyperthyroidism is: a. euthyroid sick syndrome b. goiter c. thyrotoxicosis
thyrotoxicosis
Severe hypothyroidism that develops during the newborn period is referred to as: a. myxedema b. cretinism c. thyrotoxicosis
cretinism
The limited clinical information that is available from the results of a total T4 measurement is due to: a. the fact that circadian rhythms are not determined b. interferences with circulating autoantibodies directed against the colloid c. the fact that total t4 measurements reflect inactive, protein bound hormone
c. the fact that total t4 measurements reflect inactive, protein bound hormone
A woman with thyroid cancer has her thyroglobulin (Tg) level checked to assess return of thyroid function following surgery. The Tg value was markedly decreased. Her physician calls the laboratory asking for an explanation of the result. You respond that: a. your lab uses a tg assay that likely has been interfered with by tg autoantibodies which limits the accurate measurement of tg b. tg is probably being interfered with by the immunoglobulins that are involved in the healing postsurgery process c. thyroid cancer obliterates all colloid in the thyroid gland and therefore tg will not be present in a blood sample
a. your lab uses a tg assay that likely has been interfered with by tg autoantibodies which limits the accurate measurement of tg
There is concern that the upper reference interval value for TSH is set too high to detect subtle hypothyroid disease. It is suggested that the upper reference interval value be reduced to what level to address this concern? a. 5.0 mU/L b. 2.0 mU/L c. 4.o mU/L d. 3.0 mU/L
3.0 mU/L
Which of the following thyroid hormones is considered to be the most active physiologically? a. T3 b. T4 c. DIT
T3
Which of the following laboratory tests is most useful in distinguishing between hypothalamic and pituitary causes of thyroid dysfunction? a. TSH b. T4 c. T3
TSH
In patients with developing subclinical hyperthyroidism, TSH levels will likely be …………….., and fT4 will likely be ………………... a. increased, decreased b. decreased, decreaed c. decreased, normal
decreased, normal
After treatment with medication or radioactive iodine is initiated for hyperthyroidism, disease activity is best initially monitored with………., because ………….. will take several weeks or more to return to the reference interval. a. ft3 and ft4, tsh b. tsh, t4 and t3 c. serum iodine, tsh d. tsh, ft3 and ft4
a. ft3 and ft4, tsh
Which of the following thyroid hormones normally peak at 24 to 36 hours post-delivery in a newborn and gradually fall over the first 4 weeks of life? a. ft4 b. t3 c. total t4 d. all of the above
d. all of the above
The following laboratory data are suggestive of which clinical situation? TSH – decreased; T4 – decreased; T3 – decreased; rT3 – increased a. euthyroid sick syndrome b. development of a goiter c. graves' disease
a. euthyroid sick syndrome
Given the following characteristics, which disease state is most likely? TSH – increased; fT4 – increased; fT3 – increased; T3RU – decreased; TSI – negative; TPO-ab – unlikely to be positive; Thyroid scan uptake – increased a. primary hypothyroidism b. autoimmune thyroiditis c. secondary hyperthyroidism
secondary hyperthyroidism
When free thyroxine cannot be measured directly, the free thyroxine index (FT4I) may be calculated by using which measured laboratory data? a. t4 and t3 resin uptake b. t3 and t3 resin uptake c. tsh and t4
a. t4 and t3 resin uptake
The T3 resin uptake test is used to measure: a. tbg b. total t3 c. free t3
tbg
Which of the following forms of thyroxine would be the least available to tissue receptors? a. thyroxine free in the circulation b. thyroxine bound to thyroxine-binding globulin in the circulation c. thyroxine bound to prealbumin in hthe circulation
b. thyroxine bound to thyroxine-binding globulin in the circulation
Increased TSH, decreased T3, and decreased T4 with the presence of goiter indicate: a. tertiary hypothyroidism b. secondary hypothyroidism c. primary hypothyroidism
primary hypothyroidism
What is required for normal thyroxine synthesis? a. iodine and thyroid binding globulin b. tsh, iodine, and thyroglobulin c. iodine and thyroglobuline
b. tsh, iodine, and thyroglobulin
The secretory unit of the thyroid gland is the: a. parafollicular cell b. colloid c. thyroid follicle
c. thyroid follicle
Which amino acid residue of thyroglobulin is responsible for binding iodine in the formation of thyroid hormones? a. tyrosine b. phenylalanine c. guanidine
a. tyrosine
Thyroid hormones exert influence in most areas of the body. How do thyroid hormones influence the heart? a. they cause peripheral hemodynamic alterations that influence cardiac function b. they affect cardiac gene expression c. they influence the sensitivity of the heart to the sympathetic nervous system d. all of the above
all of the above
A blood specimen is collected in a heparin-containing tube for calcium and magnesium determination. Upon centrifugation, the plasma appeared hemolyzed. How would this affect the magnesium value? a. because erythrocytes contain magnesium, hemolysis would increase its apparent value b. there would be no effect on the magnesium value c. the magnesium would be incorporated into the bilirubin molecule, leading to a false negative value
a. because erythrocytes contain magnesium, hemolysis would increase its apparent value
When a drug concentration exceeds the available metabolic capacity of the body, what does the drug’s metabolism become dependent on? a. the number of doses given per hour b. the health of the renal system c. the drug concentration itself d. the amount of metabolizing enzyme
d. the amount of metabolizing enzyme
a carbonate salt of which drug is used to control manic depressive disorders
a. digoxin b. phenytoin c. acetaminophen d. lithium
d. lithium
which of the following could account for drug toxicity following a prescribed dose? a. decreased renal elimination leading to increased free drug concentration b. increased drug metabolism caused by central nervous system disease c. using a different route of administration that is typically used for that drug
a. decreased renal elimination leading to increased free drug concentration
The fraction of drug absorbed into a physiological system that is based on the amount of drug given is referred to as: a. steady state b. dosing c. bioavailability d. volume of distribution
c. bioavailability
If a drug is acidic in nature, which of the following proteins will it associate with primarily for transport and distribution? a. albumin b. lipoprotein c. alpha1 glycoprotein d. all of the above
a. albumin
The therapeutic range of a drug is: a. dependent on the route of drug administration b. the range of concentration within which the drug is effective yet not toxic c. the range of concentration at which there are no drug interactions d. dependent on renal function
b. the range of concentration within which the drug is effective yet not toxic
The period of time during which the concentration of a therapeutic drug decays by 50% is referred to as the drug’s: a. volume of distribution b. half-life c. dosing curve d. subtherapeutic range
b. half-life
The steady state of a drug is defined as the: a. metabolism of a drug with a high hepatic extraction rate by the liver before it reaches the systemic circulation b. time required for one half of an administered drug to be lost through metabolism and elimination c. point at which the body concentration of the drug is in equilibrium with the rate of dose administered and rate of elimination
c. point at which the body concentration of the drug is in equilibrium with the rate of dose administered and rate of elimination
Respiratory alkalosis is a clinical feature of overdose ingestion of salicylate because: a. salicylates induced hyperventilation b. salicylates enhance glycolysis c. uncoupling of oxidative phosphorylation occurs in all cells
a. salicylates induced hyperventilation
An individual is found unconscious with two empty pill bottles nearby, one of aspirin and the other of phenobarbital. The best antidote for this type of double drug overdose would be: a. n-acetylcysteine b. forced alkaline diuresis c. hemodialysis
b. forced alkaline diuresis
An anticonvulsant used to control tonic-clonic (grand mal) seizures is: a. digoxin b. phenytoin c. lithium
b. phenytoin
A drug that relaxes the smooth muscles of the bronchial passages is: a. acetaminophen b. lithium c. theophylline
theophylline
Which one of the following immunosuppressant prodrugs inhibits inosine monophosphate dehydrogenase (IMPDH) to reduce the pool of intracellular guanine nucleotides and arrest T-cell proliferation? a. tacrolimus b. mycophenolate mofetil c. imipramine
b. mycophenolate mofetil
A cardiac glycoside that is used in the treatment of congenital heart failure and arrhythmias by increasing the force and velocity of myocardial contraction is: a. digoxin b. acetaminophen c. lithium d. phenytoin
a. digoxin
The main reason for suboptimal drug levels in therapeutic drug monitoring is: a. liver failure b. improper dosage prescribed c. patient noncompliance with dosage regimen d. renal failure
c. patient noncompliance with dosage regimen
Bioavailability of a drug refers to the: a. drug transformation b. availability of the protein bound fraction of the drug c. extent and rate at which the active drug reaches target tissues d. availability for therapeutic administration
c. extent and rate at which the active drug reaches target tissues
A class III antiarrhythmic drug that acts by blocking potassium channels and that is used to manage atrial fibrillation is: a. quinidine b. digoxin c. amiodarone d. procainamide
c. amiodarone
Cocaine is subject to recreational abuse because it: a. depresses the cns but not the peripheral nervous system, depending on the blood ethanol concentration to produce euphoria and decrease inhibition b. blocks dopamine reuptake at nerve synapses and prolongs the action of dopamine in the cns, leading to feelings of euphoria c.has CNS depressant effects resulting in sedation and hypnosis, and increases growth hormone release.
b. blocks dopamine reuptake at nerve synapses and prolongs the action of dopamine in the cns, leading to feelings of euphoria
A positive urine immunoassay screening test for a drug of abuse must be confirmed by: a. gc-ms b. electrophoresis c. spot test
gc-ms
The laboratory method of analysis that is accurate and precise for very low concentrations of carbon monoxide is: a. spectrophotometry b. gas chromatography c. immunoassay
b. gas chromatography
The method of monitoring therapeutic drug concentrations that is replacing HPLC-based methods and is now considered to be the best technology for analysis of biological specimens with high specificity and fewer interferences is: a. hplc b. liquid chromatography-mass spec c. spectrophotometry d. gas-liquid chroomatography
b. liquid chromatography-mass spec
For a therapeutic drug that has a short half-life, for example levetiracetam, when is the appropriate time to collect a blood sample for therapeutic drug assessment? a. there is no specific time that is best b. immediately before a dose of drug is given c. immediately after a dose of drug is given
b. immediately before a dose of drug is given
The name given to the group of enzymes that are particularly involved in phase I metabolism of drugs and that involve reduction/oxidation or hydrolysis is: a. cytochromes p-450 b. glucuronyltransferases c. methyltransferases
a. cytochromes p-450
What is the major metabolite of acetaminophen that is formed in the liver? a. sulfanilic acid b. glucuronide c. formic acid
b. glucuronide
In a clinical laboratory without gas chromatography instrumentation, the common method of choice used to measure ethanol in serum or plasma is a(n): a. enzymatic analysis using alcohol dehydrogenase and measurement of nicotinamide adenine dinucleotide formation b. immunoassay using antibodies dirrected against acetaldehyde c. potentriometric measurement of changes in voltage potential across electrodes
a. enzymatic analysis using alcohol dehydrogenase and measurement of nicotinamide adenine dinucleotide formation
In the liver, methanol is metabolized by ........... to form ........... . a. alcohol dehydrogenase; formaldehyde b. γ-glutamyltransferase; water c. aldehyde dehydrogenase; acetic acid d. methanol hydroxylase; acetaldehyde
a. alcohol dehydrogenase; formaldehyde
The laboratory method of analysis that is accurate and precise for very low concentrations of carbon monoxide is: a. potentiometry b. spectrophotometry c. gas chromatography d. immunoassay
c. gas chromatography
In which one of the following specimen types is there a strong relationship between it and plasma free drug concentration, but the window of detection is short compared with that in a urine specimen? a. hair b. oral fluid c. meconium d. serum
b, oral fluid
Which one of the following enzymes is inhibited by organophosphate or carbamate compounds, such as those found in pesticides? a. alkaline phosphatase b. acetylcholinesterase c. alcohol dehydrogenase d. amylase
b. acetylcholinesterase
A drug of abuse that stimulates the central nervous system by blocking dopamine reuptake and rapidly metabolizes to inactive benzoylecgonine and ecgonine methyl ester is: a. heroine b. ethanol c. cocaine d. methamphetamine
c. cocaine
The most common laboratory method for detection, discrimination, and quantitation of alcohols in biological specimens is: a. flame ionization gas chromatography b. hplc c. immunoassay d. spectrophotometry
a. flame ionization gas chromatography
In a chronic user of marijuana, the metabolite will remain in urine for what period of time? a. 3-4 months b. 2-7 days c. up to 73 days d. up to 3-4 weeks
c. up to 73 days
A type of drug test that is used to rule out the presence of drugs or to suggest the presence of a particular drug group and that has been replaced by rapid immunoassay tests is the ........... test. a. gas chromatography b. spot c. confirmatory d. forensic drug
b. spot
A sympathomimetic drug that can be a drug of abuse but has legitimate pharmacologic use as a treatment for narcolepsy is: a. marijuana b. fentanyl c. amphetamine d. diazepam
c. amphetamine
Because of its rapid turnaround time, the laboratory method of choice used to screen urine samples for their opiate content is: a. liquid chromatography b. ferric chloride test c. gas chromatography d. immunoassay
d. immunoassay
Cocaine is subject to recreational abuse because it: a. increases the effect of peripheral and central cholinergic nervous systems to induce feelings of happiness b. blocks dopamine reuptake at nerve synapses and prolongs the action of dopamine in the CNS, leading to feelings of euphoria. c. depresses the CNS but not the peripheral nervous system, depending on the blood ethanol concentration, to produce euphoria and decreased inhibition. d. has CNS depressant effects resulting in sedation and hypnosis, and increases growth hormone release.
b. blocks dopamine reuptake at nerve synapses and prolongs the action of dopamine in the CNS, leading to feelings of euphoria.
The enzyme responsible for the metabolism of delta-9-tetrahydrocannabinol (THC) to its various metabolites is: a. aldehyde dehydrogenase b. cyp3a c. alcohol dehydrogenase d. cyp2d6
d. cyp2d6
To recognize a poisoning pattern, groups of drugs with similar actions, symptoms, and clinical signs are examined. These common signs and symptoms are referred to as the: a. toxidrome b. pattern constellation c. toxin effect d. metabolic pattern
a. toxidrome
An example of a nonbenzodiazepine sedative-hypnotic that is used in drug-facilitated sexual assault that interacts with a subtype of the GABAA receptor complex is: a. chloral hydrate b. diazepam c. gamma hydroxbutyrate d. zolpidem
d. zolpidem
Agents related to the anticholinergic toxidrome include all of the following except: a. antihistamines b. tricyclic antidepressants c. organophosphates d. phenothiazines
c. organophosphates
Which of the following is a major active metabolite of procainamide that must be monitored along with the parent drug? a. procainamide doesn't have an active metabolite b. n-acetylprocainamide c. glycinexylidide d. disopyramide
b. n-acetylprocainamide
Which one of the following therapeutic drugs is used in the management of acute lymphoblastic leukemia and inhibits DNA synthesis by decreasing methylation of pyrimidine nucleotides and their synthesis? a. tacrolimus b. cyclosporine c. methotrexate d. mycophenolic acid
c. methotrexate
An individual who appears to be very inebriated is brought to a hospital emergency department by the police. Laboratory blood gas results indicate metabolic acidosis with an increased serum osmol gap, the presence of serum acetone, and many urine oxalate crystals. Which alcohol did this individual ingest? a. methanol b. ethylene glycol c. isopropanol d. ethanol
c. isopropanol
Which of the following best defines the term "solution"? A. A combination of two or more different chemical elements in which the atoms of the different elements are held together by chemical bonds B. A heterogeneous combination of two or more substances where the properties of each individual substance are absorbed by the other(s) C. A homogeneous mixture of two or more substances that do not chemically react with each other D. A mixture of two or more substances that results in a change in the molecular composition of each substance
C. A homogeneous mixture of two or more substances that do not chemically react with each other
A solution is composed of 1% sodium chloride and 0.5% potassium chloride in distilled water. Which substance(s) would be considered the solute? A. Potassium chloride B. Sodium chloride C. Potassium chloride and sodium chloride D. Water
C. Potassium chloride and sodium chloride
A solution in which the solvent is water is referred to as A. aqueous. B. dissolved. C. liquid. D. soluble.
A. aqueous
A vial of 3 mg silver chloride (AgCl) is poured into a flask containing 100 mL water and mixed. After 24 hours, 2.9 mg of silver chloride remains as a solid at the bottom of the flask. Which of the following terms best describes the ability of silver chloride to dissolve in water? A. Insoluble B. Partly soluble C. Soluble D. Sparingly soluble
D. Sparingly soluble
What is the risk of reporting an incorrect concentration for a patient sample? A. Administration of an inappropriate drug B. Misdiagnosis of an illness C. Both of the above D. Neither of the above
C. Both of the above
The concentration of an aqueous glucose solution is noted as 25% glucose (w/v). What does this tell us about the amount of glucose in the solution? A. There are 0.25 grams of glucose in every 100 mL of solution. B. There are 2.5 grams of glucose in every 100 mL of solution. C. There are 25 grams of glucose in every 100 mL of solution. D. There are 250 grams of glucose in every 100 mL of solution.
C. There are 25 grams of glucose in every 100 mL of solution.
The concentration of a sodium chloride (NaCl) solution is defined as 10% NaCl (w/w). What does this tell us about the amount of NaCl in the solution? A. There are 10 grams of NaCl in every 10% of solution. B. There are 10 grams of NaCl in every 100 grams of solution. C. There are 10 grams of NaCl in every 100 mL of solution. D. There are 10 grams of NaCl in every 100 ounces of solution.
B. There are 10 grams of NaCl in every 100 grams of solution.
A solution of aqueous ferric chloride has a concentration of 15 ppm. What does this tell us about the amount of ferric chloride in the solution? A. There are 15 grams of ferric chloride in every 1,000,000 grams of solution. B. There are 15 grams of ferric chloride in every 1,000,000 mL of solution. C. There are 15 mL of ferric chloride in every 1,000,000 mL of solution. D. Both A and B are correct.
D. Both A and B are correct.
When a concentration is expressed in terms of molarity, what does it tell us about the solution? A. The number of moles of a solute present in 1 liter of solution B. The number of moles of a solute present in 1,000 grams of solution C. The number of osmoles of a solute present in 1 liter of solution D. The number of osmoles of a solute present in 1,000 grams of solution
A. The number of moles of a solute present in 1 liter of solution
A solution of sodium chloride (NaCl. is calculated to be 0.5 M at 37°C. The solution was placed in an 18°C refrigerator for 24 hours and the molarity was recalculated. What would you expect the molarity of the solution to be? A. 0.5 M B. Greater than 0.5 M C. Less than 0.5 M D. It cannot be determined from the information given.
B. Greater than 0.5 M
Consider the following equation: What are the units of the value calculated by this equation? A. Molal B. Molar C. v/v D. w/v
A. Molal
What does the term "equivalent weight" mean? A. The amount of a solute that is equivalent in mass to 1 mole of the intended solvent B. The amount of a substance that contains, theoretically combines with, or theoretically replaces 1 mole of hydrogen atoms C. The molality of a solute that contains the same number of atoms as 100 grams of solvent D. The molarity of a solute that is necessary to completely saturate 100 mL of solvent
B. The amount of a substance that contains, theoretically combines with, or theoretically replaces 1 mole of hydrogen atoms
What is the rule for determining an equivalent for calculating the normality of a base or salt solution? A. An equivalent is the number of hydrogen atoms present in the base or salt. B. An equivalent is the number of hydrogen ions with which it can theoretically combine. C. An equivalent is the total number of hydroxide (OH-) groups divided by the number of hydrogen atoms present. D. An equivalent is the total number of positively charged ions present in the molecule.
B. An equivalent is the number of hydrogen ions with which it can theoretically combine.
What is the specific gravity of a solution? A. The ratio of the concentration of a solute to the concentration of the solvent at 37°C B. The ratio of the concentration of a solute to the density of water at 4°C C. The ratio of the density of a solute to the density of the solvent at 37°C D. The ratio of the density of a solution to the density of water at 4°C
D. The ratio of the density of a solution to the density of water at 4°C
Note
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