Abstract:
:A novel flow-through design for a calcium ion-selective liquid membrane and half-cell is proposed. The membrane is based on a neutral carrier for calcium and has the same quantitative chemical composition as that used in most commercial analyzers for ionized calcium (iCa2+). The membrane and half-cell follow the specifications in the Stage 1, Draft 4 document for a Reference Method for iCa2+ of the IFCC Expert Panel on pH, Blood Gases, and Electrolytes. Measurements of iCa2+ in serum with this cell confirm prior observations that protein adsorption on the membrane surface causes a rapid but reversible shift in the cell calibration signal and possible systematic errors in the measurement of iCa2+ in serum. When the protein adsorption phenomenon is maintained at equilibrium during calibrations and sample measurements, the new cell can be used to reproducibly assign iCa2+ concentrations to serum pools. These calibrated pools may then be used as reference materials and to resolve the biases known to exist among commercial iCa2+ analyzers.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
D'Orazio P,Bowers GN Jrsubject
Has Abstractpub_date
1992-07-01 00:00:00pages
1332-9issue
7eissn
0009-9147issn
1530-8561journal_volume
38pub_type
杂志文章abstract::This procedure for routine quantification of albumin in urine is based on the dye-binding properties of albumin with bromphenol blue. The absorbance of 100 microL of urine mixed with 3 mL of color reagent is measured against blank reagent at 610 nm after 30 s. Results vary linearly with albumin concentration up to 6 g...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-02-01 00:00:00
abstract:BACKGROUND:Small RNAs are key players in the regulation of gene expression and differentiation. However, many different classes of small RNAs (sRNAs) have been described with distinct biogenesis pathways and, as a result, with different biochemical properties. To analyze sRNAs by deep sequencing, complementary DNA synt...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2019.305045
更新日期:2019-12-01 00:00:00
abstract::We describe a rapid method for determining cholesterol sulfate in plasma and erythrocytes. After its single-step isolation by means of anion-exchange chromatography cholesterol sulfate is hydrolyzed, trimethylsilylated, and determined by gas chromatography with flame ionization detection. 5 beta-Cholestan-3 alpha-ol s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-07-01 00:00:00
abstract::This improved assay of rheumatoid factors in serum, described here for use with the Baker "Encore" centrifugal analyzer, is efficient, with 250-sample throughput per hour; reproducible, with between-batch CV = 5% and within-batch CV = 2% (mid-assay range); and results correlate well (r = 0.9) with those by other metho...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-02-01 00:00:00
abstract::gamma-Aminobutyric acid (GABA), an inhibitory neurotransmitter that serves about one-third of brain neurons, is involved in the development of depression and in the treatment of depression and mania with pharmacological therapy. Brain activity of GABA may be conveniently measured in plasma, and changes in plasma conce...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1994-02-01 00:00:00
abstract::Lactate dehydrogenase (LD) isoenzymes 1 and 2 in human serum were separated on a column of diethylaminoethyl-Sephadex. Samples layered on mini-columns were eluted with buffered sodium chloride (100, 150, and 200 mmol/liter). Lactate dehydrogenase activity in column effluents was measured by the Wacker method, and thei...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-03-01 00:00:00
abstract:BACKGROUND:Optimal cutoff values for tests results involving continuous variables are often derived in a data-driven way. This approach, however, may lead to overly optimistic measures of diagnostic accuracy. We evaluated the magnitude of the bias in sensitivity and specificity associated with data-driven selection of ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.096032
更新日期:2008-04-01 00:00:00
abstract::Risk can lead to catastrophe. Risk-management systems are highly effective in preventing the catastrophes of fire, earthquakes, and work-site injuries. No such effective systems are present to prevent health and social problems. A practical, cost-effective system to manage risk in children is being developed by the no...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00
abstract::The molar absorptivity of unconjugated bilirubin in caffeine reagent is independent of the protein matrix. This finding, together with the simplicity of a dilution step for direct spectrophotometry, will improve the calibration methods of bilirubin and make them more nearly accurate. This is encouraging for the develo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-07-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.147850
更新日期:2010-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1991-10-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,随机对照试验
doi:10.1373/clinchem.2006.078865
更新日期:2007-03-01 00:00:00
abstract::We describe a simple, rapid fluorometric assay for separate quantitative analysis of procainamide and N-acetylprocainamide in mixtures. The effective lenear range (fluorescence vs. concentration) in serum is 0.1 to 10.0 mg/liter, regardless of the ratio (by weight) of the two drugs from 1:10 to 10:1. Analytical recove...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-12-01 00:00:00
abstract:BACKGROUND:Extracellular matrix alterations are important elements in the arterial changes seen in diabetes, being associated with increased vascular stiffness and the development of cardiovascular diseases. However, no biomarkers for diabetes-related arterial changes have been defined. METHODS:Mammary artery specimen...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.162966
更新日期:2011-11-01 00:00:00
abstract:BACKGROUND:PS-341, a selective inhibitor of the proteasome, currently is under evaluation as an anticancer agent in multiple phase I clinical trials. In animal-model studies, PS-341 was rapidly removed from the vascular compartment and distributed widely, quickly approaching the limits of detection. An accurate pharmac...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-05-01 00:00:00
abstract::We present an improved fructosamine assay for use with the Technicon RA-1000 analyzer. Features of this assay include: specimen throughput of 100 per hour, within-batch CV of 1.5%, between-batch CV of 2.4%, standard curve linear up to 24.9 mmol of fructosamine per liter, and good correlation (r = 0.82) with hemoglobin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-12-01 00:00:00
abstract::We describe a sensitive and precise gas-chromatographic method, in which cytosine is used as the internal standard, for determination of an antifungal agent, 5-fluorocytosine, in serum. The trimethylsilyl derivative of this drug is well separated from the internal standard and from normal serum constituents. Amphoteri...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-06-01 00:00:00
abstract::We compared results obtained with the Beckman Creatinine Analyzer (Beckman Instruments, Inc.) to those with the GEMSAEC Centrifugal Analyzer (Electro-Nucleonics, Inc.) and with a manual method for determination of creatinine in serum and urine. Linearity, stability, recovery, and precision were evaluated. Interference...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-06-01 00:00:00
abstract::In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable conc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::We compared results for measurements of creatine kinase isoenzyme MB (CK-MB) by immunoinhibition vs immunoprecipitation, using sera from 53 normal healthy individuals, 55 patients with increased CK-MB associated with acute myocardial infarction, and 42 patients whose blood exhibited one or more abnormal forms of CK by...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract:BACKGROUND:Uremic syndrome is the consequence of the retention of solutes usually cleared by the healthy kidneys. p-Cresol can be considered a prototypic protein-bound uremic toxin. It is conceivable, analogous with drugs, that the non-protein-bound fraction of p-cresol exerts toxicity. This aspect had never been evalu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.3.470
更新日期:2003-03-01 00:00:00
abstract:BACKGROUND:The B-type natriuretic peptides (BNP and N-terminal pro-BNP) are secreted by the heart and, in the case of BNP, serve to maintain circulatory homeostasis through renal and vascular actions and oppose many effects of the renin-angiotensin system. Recent evidence suggests that in patients with severe heart fai...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.210435
更新日期:2014-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-07-01 00:00:00
abstract::We describe the sensitive and precise determination 5-hydroxytryptophan in plasma from patients treated with this compound. The method is based on solvent extraction of plasma, high-performance liquid chromatography and continuous fluorometric detection after reaction with phthaldialdehyde in strong acid. The combined...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00
abstract::Hepatitis A virus (HAV) infection occurs worldwide and is an important cause of acute viral hepatitis in the US. In this review, I cover the epidemiology, course of infection, clinical manifestations, serological responses, and prevention of this infection. Although most patients completely recover from this disease, ...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1997-08-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.287037
更新日期:2018-07-01 00:00:00
abstract::We have developed and validated simple, rapid immunoassays to measure concentrations of albumin in urine ranging from 5 to 200 mg/L. We use antiserum to human albumin, raised in sheep, and we separate the antibody-bound and free fractions of albumin by using a second antiserum, produced in donkeys, against the Fc frag...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-07-01 00:00:00
abstract::We have developed and evaluated a new procedure for detecting trends in quality-control measurements and applied it to laboratory data. The method requires the use of sequential or "moving" slope estimates to identify trends. Formulae are derived to estimate the regression error for the moving slope directly from the ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-03-01 00:00:00
abstract:BACKGROUND:Tartrate-resistant acid phosphatase (AcP) 5b is a marker of osteoclastic activity and bone resorption. Immunoassays for serum TRAcP may lack sensitivity and specificity because of the presence of non-bone isoform 5a. The purpose of this study was to isolate the serum isoforms, quantify their disease-related ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2001-01-01 00:00:00