Clinical Final Flashcards
What is the purpose of centrifugal force in centrifugal analyzers?
Mix sample and reagents, transfer reagents into separate analyzing chambers
What do the etched ring on the top of a pipet mean?
pipet should be blown out
What does TC on the top of a pipet mean?
to contain, to be blown out with diluting fluid
Why is CO toxic?
has a high affinity with hemoglobin, 250x stronger than oxygen
What are some precautions for bilirubin specimen handling?
protect from light, analyze no later than 2-3 hours after blood clotted
What enzyme test cannot be preserved by freezing?
lactate dehydrogenase
What is the cause of postprandial lipemia?
chylomicrons
How does the electrophoresis pattern of plasma differ from that of serum?
fibrinogen spike in the gamma region
What is the order of migration of proteins on electrophoresis at pH 8.6?
a1, a2, B, and gamma
What is the principle enzyme in saliva?
amylase
The immunoglobulins migrate with what protein on electrophoresis at pH 8.6?
albumin
How do contraceptives affect total T4 and TBG in competitive binding assays?
affects the glycosylation of TBG and delays its clearance leading to an increased serum concentration of TBG and sits on T4 causing a decrease in free T4. This causes an increase in total T4, appearing as hyperthyroidism
Creatinine is the breakdown product of what substance?
creatine
With are some clinically significant metabolites of some hormones?
VMA, 5-HIAA, HVA, metanephrine, normetanephrine, estrone, estradiol-17B, estriol
What tests are affected by hemolysis?
potassium
What is the normal bicarbonate to dissolved CO2 ratio?
20:1
What is the anticoagulant of choice for blood gas analysis?
sodium heparin
How is serum globulin usually determined?
(total protein) - (albumin)
What is the predominant form of thyroid hormone in the circulation?
T4
How is a bloody CSF handled in the chemistry lab?
Centrifuged and ran as normal
What is the unique value of enzymes as reagents?
act as natural catalytic substances
What are the major intracellular and extracellular cations and anions?
Na, K, Cl
What is the normal pH of blood?
7.4
What does the PCO2 electrode actually measure?
transfer of hydrogen ions
Describe transudate
clear, no clots, SG
Describe exudate
cloudy, clots, SG >1.015, TP >30 g/L, cellular
What protein is a contributing factor in edema formation?
albumin
How is the blood glucose level affected in the serum is left sitting on the clot for several hours
metabolism of the RBCs can significantly reduce blood glucose level
What is the most accurate pipet for measuring a 1 mL volume?
volumetric
What typ elf fast does the patient undergo for lipid studies?
12 hour fast, normal diet for 2 weeks prior
What is the principle of the Kjeldahl protein technique?
involves the conversion of protein nitrogen into ammonium ion using acid digestion
What is the principle of iron binding capacity?
saturation of transferrin with excess iron then removal of unbound iron
What is the principle of the Biuret method?
cupric ions react with peptide bonds to form a violet color the intensity of which is directly proportional to the number of peptide bonds present
What is the principle of the nephlometry?
measuring concentration in terms of the light energy that is scattered in a forward direction by small particles in solution
What is the principle of the fluorometry?
photometric measurement of the ability of a molecule to become excited and absorb light at one wavelength, but to emit light at another wavelength
What is the principle of the oral GTT?
evaluates the insulin response to a glucose challenge
What is glycosylated hemoglobin?
tests patients compliance with insulin therapy in the last 8-12 weeks
What is intrinsic factor?
Promotes vitamin B12 absorption in the small intestine
What is the Jaffe reaction?
most common method for creatinine determinations
What is kernicterus?
infiltration of the brain & spinal cord with unconjugated bili which causes permanent damage to CNS
What is Beer’s Law?
concentration (C) of a substance is directly proportional to the amount of light absorbed by the solution or inversely proportional to the logarithm of transmitted light
What is the hollow cathode lamp?
the light source in the atomic absorption spectrophotometry
What is a pheochromocytoma?
tumors of the adrenal medullary chromaffin tissue
What is VMA?
metabolite of epinephrine and norepinephrine
What is 5-HIAA?
metabolite of serotonin
What is the Berthelot reaction?
hydrolysis urea to ammonium carbonate by the enzyme urease
What is the reagent used in prostatic acid phosphatase?
thymolphthalein monophosphate
What is the reagent used in urobilinogen determinations?
p-dimethylaminobenzaldehyde
What are urinary 17-ketosteroids?
products from the breakdown of androgens
What is the significance of duodenal fluid testing?
useful in the detection of chronic parcreatits, pancreatic insufficiencies, and cystic fibrosis
What is the clinical significance of HDL cholesterol?
risk of artherosclerosis
What is the clinical significance of AFP?
tumor marker used in the detection of cancers of the testes, ovaries, and liver
What is the clinical significance of LD?
diagnosis of cardiac, hepatic, skeletal muscle, and renal disease
What is the clinical significance of uric acid?
waste product derived from purines in the diet and the breakdown of nucleic acid
What is the clinical significance of SGOT/AST?
elevated in MI, viral hepatitis, and skeletal muscle disease
What is the clinical significance of amylase?
for the diagnosis of acute pancreatitis
What is the clinical significance of creatinine?
Disorders of kidney function prevent maximum excretion of creatinine and its levels increase in the blood
What is the clinical significance of ALT?
diagnosis and evaluation of hepatocellular disease
What is the clinical significance of anion gap?
body normally exists in a state of electroneutrality in which the sum of the cations equals the sum of the anions
Patients with an increased catabolism of purines most likely have an increased serum concentration of what substance?
uric acid
The serum protein electrophoresis pattern in multiple myeloma shows what abnormality?
fibrinogen spike in the gamma region
What are the normal values of LDL?
50-130 mg/dL
What are the normal values of HDL?
40-75 mg/dL
What are the normal values of cholesterol?
140-200 mg/dL
What are the normal values of triglycerides?
60-150 mg/dL
What substance in the intestines is required for the absorption of vitamin B12?
intrinsic factor
List three enzymes whose clinical significance is related to the detection of a MI?
AST, CK, LD