Abstract:
:Since 1991, the Ontario Laboratory Proficiency Testing Program has assessed the analytical performance of creatine kinase (CK; EC 2.7.3.2) isoenzyme-2, using fresh human serum supplemented with purified human CK isoenzymes. In Ontario, the 142 laboratories licensed to analyze CK-2 use a variety of methods: electrophoresis-based, immunoinhibition, and mass assays. During a 1992 survey, duplicate CK-2 samples with different total CK activities showed poorer precision when analyzed after electrophoretic separation than by any other method. A 1993 survey designed to validate these observations conclusively showed that electrophoresis-based assays are subject to a bias proportional to the total CK activity. These survey results were confirmed by studies with selected patients' specimens. We therefore conclude that electrophoresis-based assays may not warrant their reputation as the gold standard for CK isoenzyme measurement.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Henderson AR,Stark JA,McQueen MJ,Patten RL,Krishnan S,Wood DE,Webb Ssubject
Has Abstractpub_date
1994-02-01 00:00:00pages
177-83issue
2eissn
0009-9147issn
1530-8561journal_volume
40pub_type
杂志文章abstract::Monoclonal antibodies were raised against neuron-specific enolase, gamma gamma-enolase, and used in an immunoradiometric assay (IRMA), with mono-disperse magnetizable particles as the solid phase. The assay's sensitivity was 0.4 microgram/L and the interassay coefficient of variation was less than 5% in the working ra...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-10-01 00:00:00
abstract::We describe a chromatographic system involving a high-performance chemically-bonded reverse-phase column and fluorescence detection for measurement of indoles in urine. We controlled retention and selectivity by optimizing the methanol content and pH of the mobile phase. Six reference indoles were separated in less th...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-02-01 00:00:00
abstract:BACKGROUND:With the gradual reopening of economies and resumption of social life, robust surveillance mechanisms should be implemented to control the ongoing COVID-19 pandemic. Unlike RT-qPCR, SARS-CoV-2 whole genome sequencing (cWGS) has the added advantage of identifying cryptic origins of the virus, and the extent o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa187
更新日期:2020-11-01 00:00:00
abstract:BACKGROUND:Soluble CD146 (sCD146), is an endothelial marker with similar diagnostic power as natriuretic peptides in decompensated heart failure (HF). While natriuretic peptides are released by the failing heart, sCD146 may be released by veins in response to stretch induced by systemic congestion in HF. This study inv...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:10.1373/clinchem.2016.260471
更新日期:2017-01-01 00:00:00
abstract:BACKGROUND:Methylmalonic acid (MMA) in plasma or serum is widely used for assessment of vitamin B(12) status. However, data are sparse regarding factors, besides renal function, that may influence MMA concentrations. We searched for important determinants of plasma MMA in the general population. METHODS:In 6946 middle...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.128678
更新日期:2009-12-01 00:00:00
abstract::Development of a new, sensitive immunoassay for measuring transforming growth factor beta 1 (TGF-beta1) is described and compared with four commercially available TGF-beta1 immunoassays. Preanalytical conditions were evaluated. The nonlinearity found in serum or plasma is due to masking of TGF-beta1 by binding protein...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-10-01 00:00:00
abstract::Four double-monoclonal time-resolved immunofluorometric assays (TrIFMAs) have been developed for the specific determination of pregnancy-associated plasma protein A/proeosinophil major basic protein (PAPP-A/ proMBP) complex in first-trimester maternal serum samples. The assays have a functional sensitivity of < 4 mIU/...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
abstract::Carbohydrate-deficient transferrin (CDT) may now be the most valuable biological marker for diagnosis of alcohol abuse. We compared the diagnostic performance of two new CDT tests, Axis %CDT turbidimetric immunoassay (TIA) and Axis %CDT HPLC, against Specialty Laboratories' isoelectric focusing/immunoblotting/laser de...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1997-06-01 00:00:00
abstract::Synovial fluid samples were collected from 45 patients with rheumatoid arthritis, spondylarthropathy, or osteoarthritis, to study their content of elastase (EC 3.4.21.37) and of cysteine proteinases (EC 3.4.22.1, 3.4.22.15). We measured both elastase complexed with alpha 1-proteinase inhibitor and elastase activity to...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract::A plasma protein required for the support of ristocetin-induced platelet aggregation was isolated from antihemophilic factor concentrate and radiolabeled with 125I. A double-antibody radioimmunoassay was developed, with use of specific rabbit anti-VIII related antigen serum and goat anti-rabbit globulin. The assay is ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-09-01 00:00:00
abstract::We describe a novel radioimmunoassay procedure for the direct estimation of aldosterone in unextracted plasma and serum samples, in which interfering binding proteins are digested by Proteinase K (Tritirachium alkaline proteinase, EC 3.4.21.14), a powerful proteolytic enzyme. Heating at 75 degrees C for 15 min inactiv...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-12-01 00:00:00
abstract::We have assessed Calbiochem single-vial enzymatic reagent systems for the analysis for cholesterol and triglycerides, using manual and centrifugal analyzer techniques. Analysis for cholesterol by both techniques had acceptable performance by the short-term criteria of the Center for Disease Control (CDC) during this s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-11-01 00:00:00
abstract:BACKGROUND:We investigated agreement between self-reported prenatal alcohol exposure (PAE) and objective meconium alcohol markers to determine the optimal meconium marker and threshold for identifying PAE. METHODS:Meconium fatty acid ethyl esters (FAEE), ethyl glucuronide (EtG), and ethyl sulfate (EtS) were quantified...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2014.233718
更新日期:2015-03-01 00:00:00
abstract::Intra-erythrocytic pH, ATP concentrations, and 2,3-diphosphoglycerate relaxation times were studied in living erythrocytes by "high-resolution" 31P NMR spectroscopy to assess homeostasis within the cells. In uremic patients, intra-erythrocytic pH is significantly decreased before hemodialysis, but is corrected equally...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
abstract:BACKGROUND:Recent studies show that the haptoglobin phenotype in individuals with diabetes mellitus is an important factor for predicting the risk of myocardial infarction, cardiovascular death, and stroke. Current methods for haptoglobin phenotyping include PCR and gel electrophoresis. A need exists for a reliable met...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.244004
更新日期:2016-01-01 00:00:00
abstract::We report here the evaluation of the Abbott TDx assay with a monoclonal antibody for selectively quantifying cyclosporine (CsA) in whole blood. Over the clinically relevant concentration ranges, results with this assay demonstrated within- and between-run CVs of less than 2.5% and 5%, respectively; sensitivity of 25 m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-11-01 00:00:00
abstract::Serum amyloid A (SAA), a sensitive acute-phase protein, is the precursor of AA fibrils in reactive amyloidosis. However, SAA is poorly immunogenic, and development and standardization of immunoassays of this protein have been difficult. We established an automated polyclonal/monoclonal microparticle capture enzyme imm...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-07-01 00:00:00
abstract:BACKGROUND:We describe a simple tetra-primer amplification refractory mutation system PCR (T-ARMS-PCR) for detecting MUTYH mutations, which are associated with colorectal adenomas and colorectal cancer. METHODS:We designed specific T-ARMS-PCR assays for 6 mutations (Y165C, G382D, 1395_7delGGA, Y90X, 1103delC, and R231...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.060137
更新日期:2006-04-01 00:00:00
abstract:BACKGROUND:Blockade of the renin-angiotensin system (RAS) represents a main strategy in the therapy of heart failure with reduced ejection fraction (HFrEF), but the role of active renin concentration (ARC) for guiding therapy in the presence of an RAS blockade remains to be established. This study assessed angiotensin ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2017.278705
更新日期:2018-03-01 00:00:00
abstract::With use of a specially designed gradient-generating system, of anion-exchange resins of 10-20 mum particle diameter, and of an orcinol solution in concentrated sulfuric acid (1 g/liter) as detection reagent, a mixture of 16 carbohydrates can be separated in less than 4 h. The limit of detection for most sugars is in ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-12-01 00:00:00
abstract::One currently observes many healthcare institutions rushing to reengineer and install information systems with the expectation of achieving enhanced efficiency, competitiveness, and, it is hoped, higher patient satisfaction resulting from timely, high-quality care. Unfortunately, information system concepts, design, a...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1995-09-01 00:00:00
abstract:BACKGROUND:Concerns exist regarding how the 99th percentile upper reference limit (URL) of cardiac troponin (cTn) is determined and whether it should be derived from normal healthy individuals. CONTENT:The 99th percentile URL of cTn is an important criterion to standardize the diagnosis of myocardial infarction (MI) f...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa158
更新日期:2020-09-01 00:00:00
abstract::Gene mutations responsible for the majority of Duchenne/Becker muscular dystrophy (DMD/BMD) and cystic fibrosis (CF) chromosomes have been identified. We describe a DNA-based strategy, rather than the traditional biochemical assays, for screening newborns. DNA sequences spanning the CF mutation and several DMD/BMD del...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-10-01 00:00:00
abstract::Values of low-density lipoprotein (LDL) cholesterol (C) according to the Friedewald formula (Clin Chem 1972;18:499-502) were compared with those obtained by lipoprotein fractionation in 98 healthy subjects (control group), 135 specimens from patients with peripheral vascular and cerebrovascular disease (atheroscleroti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-08-01 00:00:00
abstract::Total protein (TP), albumin (Alb), transferrin (TRF), retinol-binding protein (RPB), N-acetyl-beta-glucosaminidase (NAG), alanine aminopeptidase (AAP), gamma-glutamyltransferase (GGT), and creatinine (Cr) were measured in random (untimed) urine samples from 29 nonpregnant women and from pregnant subjects (11 in the fi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-09-01 00:00:00
abstract:BACKGROUND:Hypoxic ischemic encephalopathy (HIE) is a major cause of permanent neurological disabilities in full-term newborns. We measured activin A in urine collected immediately after birth in asphyxiated full-term newborns, and assessed the ability of the measurements to predict the occurrence of perinatal encephal...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.062604
更新日期:2007-03-01 00:00:00
abstract::A micro version of a nuclear binding assay to assess the biological activity of receptors for steroid hormones was developed for application to small (needle) biopsies of human tumors for the purpose of predicting responses to steroid therapy. This easier assay requires 10-fold less tissue than the original nuclear bi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-02-01 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::Patients' urines gave an unexpectedly high percentage of false-negative results for erythrocytes on a reagent strip, even when the test field for ascorbic acid indicated that none of this substance was present to inhibit the test reaction. By adding known amounts of erythrocytes to normal urines, we found that this ph...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
abstract::We have explored the method of Rapoport et al. (J Clin Endocrinol Metab 1984;58:332-8) for the bioassay of thyroid-stimulating immunoglobulin (TSI) in cultured human thyroid cells, to optimize the assay and to evaluate its utility in clinical diagnosis and management of patients with autoimmune thyroid disease. Here w...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-02-01 00:00:00