Abstract:
:We compared different sample-handling techniques for measurement of Na+ and K+ with ion-selective electrodes (ISE). Imprecision was less for venous blood (with a minimum of heparin) than for plasma, serum, or capillary blood. The results for K+ were higher for serum than for whole blood, and higher for whole blood than for plasma. The latter difference was apparently due to release of K+ during the analysis. Values were more stable for whole blood stored at 20 degrees C than at 4 degrees C or 37 degrees C. The molality of Na+ in the plasma of mixed whole blood changed by -10.5 mmol/kg per unit change in blood pH. This could be explained by the different H+ buffering capacities of plasma and erythrocyte fluid, because when the pH is changed, the concentration of small anions in erythrocytes changes more than it does in plasma, with a consequent osmotic movement of water across the erythrocyte membrane. When we took into account the residual liquid-junction potential and the mass concentration of water in each of 65 patients' sera, the molality determined for Na+ was 1% lower and that of K+ 3% lower by ISE than by flame photometry--differences that may be related to ionic binding or to a lower molal activity coefficient in serum than in the calibrator.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Fogh-Andersen N,Wimberley PD,Thode J,Siggaard-Andersen Osubject
Has Abstractpub_date
1984-03-01 00:00:00pages
433-6issue
3eissn
0009-9147issn
1530-8561journal_volume
30pub_type
杂志文章abstract::We describe a sensitive, simple, and rapid two-site immunoenzymometric assay for thyrotropin in dried blood samples on filter paper, for use in screening for neonatal primary hypothyroidism. In this method, two dried-blood spots of 3 mm diameter (equivalent to about 5.4 microliter of blood) are incubated overnight wit...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-08-01 00:00:00
abstract:BACKGROUND:At concentrations <500 microg/L, serum alpha-fetoprotein (AFP) has low specificity in the diagnosis of hepatocellular carcinoma (HCC), but monosialylated AFP (msAFP) is more specific for HCC. We describe two strategies for quantitative analysis of msAFP and explore their diagnostic accuracy in cases of HCC w...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-07-01 00:00:00
abstract::Fast lipoprotein chromatography (FLPC) is a novel method for quantifying lipoproteins. Plasma proteins are separated by fast-flow gel filtration. Lipoproteins are detected by post-column derivatization with an enzymatic cholesterol reagent. FLPC resolves very-low-, low-, and high-density lipoproteins (VLDL, LDL, and H...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-11-01 00:00:00
abstract:BACKGROUND:To determine the contribution of laboratory costs to the overall costs of managing hospital patients with different diseases, we studied the costs of laboratory testing overall and in relation to the other costs incurred during hospitalization. METHODS:We used a database developed by the University HealthSy...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-07-01 00:00:00
abstract::In this report on trace-element concentrations (As, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Zn) in human heart, liver, kidney, aorta, and rib obtained from 200 autopsied patients, we give special attention to sampling procedure, analysis technique, and various sources of error (autolysis...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-11-01 00:00:00
abstract::In the diagnosis of chronic (as opposed to acute) liver diseases, combinations of indicators are needed to improve specificity. Alanine aminopeptidase (AAP; microsomal aminopeptidase, EC 3.4.11.2) activity in serum reportedly is a very sensitive indicator of intrahepatic cholestasis and biliary obstruction; it is also...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-03-01 00:00:00
abstract:BACKGROUND:Noninvasive prenatal testing (NIPT) uses cell-free DNA (cfDNA) as an analyte to detect copy-number alterations in the fetal genome. Because maternal and fetal cfDNA contributions are comingled, changes in the maternal genome can manifest as abnormal NIPT results. Circulating tumor DNA (ctDNA) present in case...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2017.277517
更新日期:2018-02-01 00:00:00
abstract:BACKGROUND:Near-infrared spectroscopy is proposed as a method for providing real-time urea concentrations during hemodialysis treatments. The feasibility of such noninvasive urea measurements is evaluated in undiluted dialysate fluid. METHODS:Near-infrared spectra were collected from calibration solutions of urea prep...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2001-01-01 00:00:00
abstract::We measured the cross reactivity of two medications--digitoxin and spironolactone--in two digoxin radioimmunoassay (liquid and solid-phase) kit procedures. Both tests showed similar average percentages of cross reactivity with digitoxin (7.2 and 8.9% for intravenous, and 11.9 and 10.9% for oral administration), but no...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-04-01 00:00:00
abstract::Three groups of 10 age- and sex-matched nondiabetic volunteers took 0, 750, or 1500 mg of vitamin C each day for 12 weeks. Glycohemoglobin (GHb) was measured by HPLC, electrophoresis, affinity chromatography, and immunoassay at baseline (-4 weeks and -1 day), during supplementation (6 weeks and 12 weeks), and after su...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-05-01 00:00:00
abstract::We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::We used ion-exchange column chromatography and electrophoresis on polyacrylamide gel to compare the acid phosphatase isoenzymes of prostate and leukocytes. The major isoenzyme of the prostate is band 2A; only a trace of band 2B was observed. However, the major isoenzymes of leukocytes are band 4 and band 2B, and only ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-07-01 00:00:00
abstract::We measured the concentration of carboxyhemoglobin (HbCO) in blood samples from 32 neonates by spectrophotometry (IL282 CO-Oximeter) and gas chromatography, finding a strong positive correlation (r = 0.89) between the concentration of fetal hemoglobin (Hb F) and HbCO as measured by spectrophotometry, but not by gas ch...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-05-01 00:00:00
abstract::alpha 1-Antitrypsin (A1AT) deficiency is a relatively common autosomal recessive disease, resulting most often from a single base pair (1 bp) substitution called the Z mutation. Previous genetic tests for carriers and affected patients have relied on quantitative binding of radioactive probes to an amplified gene prod...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00
abstract::We describe a sensitive beta-endorphin (beta-EP) radioimmunoassay specific for beta-EP 1-31 applied to human ventricular and lumbar cerebrospinal fluid (CSF). Specificity was documented by reversed-phase HPLC of CSF pools. Simultaneous ventricular and lumbar CSF samples from 13 patients suspected of having normal-pres...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-06-01 00:00:00
abstract::We describe a direct radioimmunoassay for serotonin (5-hydroxytryptamine) in cerebrospinal fluid, platelet-poor plasma, and serum. We raised antisera in rabbits against serotonin diazotized to a conjugate of bovine albumin and D,L-p-aminophenylalanine. Polyethylene glycol, alone or in combination with anti-rabbit immu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-04-01 00:00:00
abstract::To determine the molar absorptivities of beta-NADH and beta-NAD at 260 nm, we purified the reduced form of the coenzyme by repeated anion-exchange chromatography. A NADH preparation was so obtained for which the 260 nm/340 nm absorbance ratio was 2.265. When calculated with epsilon 340 beta-NADH = 6.22 times 10-3 for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-06-01 00:00:00
abstract::We compared the effects of freezing serum on the determination of high-density lipoprotein (HDL) subfractions by two dual-precipitation methods, heparin and manganese chloride/dextran sulfate (HM/DS) (Gidez et al., J Lipid Res 1982;23:1206-23) and DS/DS (Warnick et al., Clin Chem 1982;28:1574), and by ultracentrifugat...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-09-01 00:00:00
abstract::To evaluate their potential usefulness in the differential diagnosis of Cushing's syndrome, we estimated the urinary excretion rates of the following non-metabolized, unbound steroid hormones: pregnenolone, progesterone, 17-OH-pregnenolone, 17-OH-progesterone, dehydroepiandrosterone (DHEA), androstenedione, testostero...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-01-01 00:00:00
abstract::We evaluated the EMIT Cyclosporine Assay (Syva Co., Palo Alto, CA), using the Cobas-Mira analyzer to assess the precision, accuracy, and analytical recovery from whole-blood samples supplemented with cyclosporine. We also performed comparative analysis of whole-blood samples containing cyclosporine from liver and kidn...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract:BACKGROUND:The gene that causes most cases of hereditary hemochromatosis is designated HFE. Individuals with mutations in the HFE gene may have increased serum iron, transferrin saturation, and ferritin concentrations relative to individuals with the wild-type genotype. METHODS:We generated reference centiles for perc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2001-10-01 00:00:00
abstract::We have reported (Clin Chem 29: 42-44, 1983) that prestaining with Remazol Brilliant Blue permits direct visualization of serum components on disc electrophoresis, and apparently purifies the proteins well. Here we have cut out the bands corresponding to the prestained albumin and transferrin after disc electrophoresi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-07-01 00:00:00
abstract:BACKGROUND:Detection of circulating tumor cells (CTCs) in the peripheral blood is a rapidly developing research field with clear clinical implications for the staging and monitoring of cancer patients. Current CTC assays, including the US Food and Drug Administration-cleared CellSearch® system, typically use markers [e...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.175570
更新日期:2012-05-01 00:00:00
abstract::We describe a convenient, economical procedure for measuring uroporphyrinogen I synthase (EC 4.3 1.8) activity in erythrocytes, the results of which can be used to diagnose acute intermittent porphyria, in either its latent or acute stage. By limiting the test reaction sequence to the conversion of porphobilinogen to ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-07-01 00:00:00
abstract::Using Syva "EMIT" reagents and the Cobas Bio centrifugal analyzer, we have developed cost-effective assays for therapeutic drug monitoring of carbamazepine, phenobarbital, and phenytoin. With these optimized methods one can assay up to 2470 samples with a single 100-test EMIT kit with good precision and accuracy. Betw...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
abstract::We describe a multiprobe colorimeter that permits the reading of enzyme-linked immunosorbent assays (ELISA) in situ, by use of microhemagglutination plates. The use of dipping probes eliminates interference from meniscus effects and air-bubble entrapment. Detailed validation tests have been done and potential sources ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00
abstract::Using the Selected Method of McKenzie and Henderson (Selected Methods Clin Chem 1983;10:59-67) as a reference method, we compared the performance of 10 commercially available methods for determination of lactate dehydrogenase (LD, EC 1.1.1.27) isoenzymes. Results were expressed as percentage of total LD activity, as d...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-09-01 00:00:00
abstract::The location of the Reference Value for an analyte within the population distribution affects the magnitude of error due to methodological bias. Using the gaussian distribution, we evaluated the effects of systematic and proportional biases of the method (positive and negative), mean value, and standard deviation on t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-11-01 00:00:00
abstract:BACKGROUND:External quality assurance (EQA) programs for diagnostic tests based on nucleic acid amplification have not been widely implemented in clinical laboratories and remain limited to few tests. Development of specific EQA programs based on application-based proficiency testing for any diagnostic molecular target...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.5.782
更新日期:2003-05-01 00:00:00
abstract::The pattern of organic acids in urine from 15 normal newborn infants was investigated by gas chromatography/mass spectrometry of trimethylsilylated derivatives. The urine contains large amounts of succinic, fumaric, 2-ketoglutaric, and 3-hydroxy-3-methylglutaric acids, which are all fairly small components of urine fr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-01-01 00:00:00