Abstract:
:We describe an automated enzymatic procedure for quantifying creatine in erythrocytes. In this assay, after sample clean-up, creatine kinase (CK; EC 2.7.3.2) and pyruvate kinase (EC 2.1.7.40) are used as auxiliary enzymes; lactate dehydrogenase (EC 1.1.1.27) is used in the indicator reaction. CK is also used as the starting reagent. Data obtained with the present method (y) correlated as follows with those from the comparison method (x) for creatine measurement in erythrocytes (colorimetric, diacetyl-alpha-naphthol): y = 1.017x - 27.5 (S(y/x) = 11.9, r = 0.997). Precision data were obtained by analyzing three different samples of erythrocytes nine times per day for 25 days with both methods. The total CVs determined by our method and the comparison method were respectively 3.0-4.8% (measured creatine range, 171-463 micromol/L) and 5.1-7.1% (creatine, 185-485 micromol/L). We established the reference interval (mean +/- 2SD) for creatine in erythrocytes from healthy individuals as 194-538 micromol/L for men (n = 71) and 241-677 micromol/L for women (n = 100). Using erythrocytes from patients with various hematological abnormalities and chronic renal failure, who were being treated with continuous ambulatory peritoneal dialysis or hemodialysis, we performed a clinical evaluation and obtained results in agreement with existing data on biochemical markers for the mean age of erythrocytes.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Beyer C,Alting IHsubject
Has Abstractpub_date
1996-02-01 00:00:00pages
313-8issue
2eissn
0009-9147issn
1530-8561journal_volume
42pub_type
杂志文章abstract::We describe an enzyme-linked immunosorbent assay for determination of light-chain ratios for IgG, IgA, and IgM in serum. A commercial serum with known overall kappa and lambda concentrations was used as standard. To capture the respective immunoglobulins, we used antibodies to gamma, lambda and mu chains coated onto m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-03-01 00:00:00
abstract:BACKGROUND:The "unit" for "enzymic activity" (U = 1 micromol/min) was recommended by the International Union of Biochemistry and Molecular Biology (IUB) in 1961 and is widely used in medical laboratory reports. The general trend in metrology, however, is toward global standardization through defining units coherent wit...
journal_title:Clinical chemistry
pub_type: 历史文章,杂志文章
doi:
更新日期:2002-03-01 00:00:00
abstract::We present a simple method for subclass typing of IgG paraproteins, with which we have demonstrated a large number of paraproteins that were undetected by conventional immunofixation techniques. The types and distribution of IgG subclass paraproteins were analyzed in 92 human sera in which IgG paraproteins had been de...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-10-01 00:00:00
abstract:BACKGROUND:24,25-Dihydroxyvitamin D [24,25(OH)2D] in serum may be both a nuisance and nutritionally valuable. METHODS:We investigated the impact of 24,25(OH)2D3 on the performance of commercially available immunoassays for serum total 25-hydroxyvitamin D [25(OH)D] using (a) serum from a nationally representative sampl...
journal_title:Clinical chemistry
pub_type: 杂志文章,随机对照试验
doi:10.1373/clinchem.2014.234955
更新日期:2015-04-01 00:00:00
abstract:BACKGROUND:In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a comprehensive general unknown screening method based on liquid chromatography coupled with a hybrid triple-quadrupole linear ion trap mass spectrometer. MET...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.067116
更新日期:2006-09-01 00:00:00
abstract:BACKGROUND:Lysosomal storage disorders (LSDs) comprise more than 40 genetic diseases that result in the accumulation of products that would normally be degraded by lysosomal enzymes. A tandem mass spectrometry (MS/MS)-based method is available for newborn screening for 5 LSDs, and many laboratories are initiating pilot...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.111864
更新日期:2009-01-01 00:00:00
abstract:BACKGROUND:Band 5 tartrate-resistant acid phosphatase (TrACP; EC 3. 1.3.2) consists of two isoenzymes, bands 5a and 5b, of which band 5b TrACP is considered to be derived from bone. However, no kinetic method for the specific measurement of band 5b TrACP in serum is available. Our aim was to develop a kinetic assay met...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-04-01 00:00:00
abstract::We used a previously reported agarose-gel electrophoresis system to study the lipoprotein patterns in patients with type 3 hyperlipoproteinemia. All samples from 20 subjects tested revealed the presence of two bands with beta-lipoprotein mobility, irrespective of quantitative changes in plasma lipids induced by diet o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-06-01 00:00:00
abstract:BACKGROUND:The use of nonstandardized N-terminal pro-B-type natriuretic peptide (NT-proBNP) assays can contribute to the misdiagnosis of heart failure (HF). Moreover, there is yet to be established a common consensus regarding the circulating forms of NT-proBNP being used in current assays. We aimed to characterize and...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.200204
更新日期:2013-10-01 00:00:00
abstract:BACKGROUND:Apolipoprotein (apo) E is a component of two major classes of plasma lipoproteins, apo B- (apo E-LpB) and non-apo B-containing (apo E-Lp-non-B) lipoproteins. The factors that affect total apo E in particles [lipoprotein E (LpE), apo E-Lp-non-B, and apo E-LpB], are incompletely characterized. METHODS:We stud...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-02-01 00:00:00
abstract::Brain proteins extractable with distilled water or 9 mol/L urea were subjected to two-dimensional gel electrophoresis. They are examined in relation to the identification of actin, tubulin, neurofilament proteins, glial fibrillary acidic protein; proteins of human embryonic neocortex, synaptosomes, myelin, and plasma;...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-04-01 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:BACKGROUND:The optimal situation in external quality assessment (EQA) is to use commutable materials. No previous study has examined the commutability of a whole-blood material for point-of-care (POC) testing. The aim of this study was to determine the commutability of the Norwegian Quality Improvement of Laboratory Ex...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.300202
更新日期:2019-06-01 00:00:00
abstract::We describe the influence of autoantibodies that bind creatine kinase BB (CK-BB) on the methods for MB isoenzyme. If these autoantibodies are present in patients' sera, they cause the formation of macro CK type 1 (immunoglobulin-linked CK-BB). In some of these cases they can bind not only endogenous CK-BB but also CK-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-07-01 00:00:00
abstract::A method is presented for the assay of delta-aminolaevulinate dehydratase (EC 4.2.1.24) to be performed on 10 microL of whole blood. Results compare favorably with those obtained with an accepted method (J. Clin. Chem. Clin. Bio-chem. 12: 389-390, 1974) that involves use of 200 microL of blood. ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-01-01 00:00:00
abstract::We studied chemical speciation of arsenic compounds in urine samples by using HPLC with inductively coupled plasma mass spectrometry detection. We examined urinary arsenic excretion patterns and the arsenic species excreted from nine human subjects who ingested seaweed products and crab (or shrimp). Fast urinary excre...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-04-01 00:00:00
abstract:BACKGROUND:Spurious increases in serum troponins, especially troponin T, have been reported in patients with and without acute myocardial syndromes. METHODS:We studied 78 autopsied patients without clinical myocardial infarction (MI) and correlated histologic cardiac findings with antemortem serum creatine kinase (CK)...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-03-01 00:00:00
abstract:BACKGROUND:SELDI-TOF mass spectrometry (MS) is a high-throughput proteomic approach with potential for identifying novel forms of serum biomarkers of arthritis. METHODS:We used SELDI-TOF MS to analyze serum samples from patients with various forms of inflammatory arthritis. Several protein profiles were collected on d...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.099549
更新日期:2008-06-01 00:00:00
abstract::By using bivariate probability estimation for the diagnosis of acute myocardial infarction (AMI) we show how to overcome the difficulties encountered for patients whose clinical presentation is atypical and those encountered when multiple isoenzyme determinations are treated by univariate methods. We use the values fo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-03-01 00:00:00
abstract:BACKGROUND:The diagnosis of 22q11 deletion syndrome (22q11DS) is often delayed or missed due to the wide spectrum of clinical involvement ranging from mild to severe, often life-threatening conditions. A delayed diagnosis can lead to life-long health issues that could be ameliorated with early intervention and treatmen...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2014.230086
更新日期:2015-01-01 00:00:00
abstract::Investigating the interference of danazol in testosterone radioimmunoassays, we measured serum testosterone concentrations in the serum of women receiving danazol, with three testosterone radioimmunoassay kits. All of these showed positive interference by danazol or its metabolites (or both). Values for testosterone o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-01-01 00:00:00
abstract:BACKGROUND:Next generation sequencing (NGS)-based assays continue to redefine the field of genetic testing. Owing to the complexity of the data, bioinformatics has become a necessary component in any laboratory implementing a clinical NGS test. CONTENT:The computational components of an NGS-based work flow can be conc...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2014.224360
更新日期:2015-01-01 00:00:00
abstract::We describe a procedure for determining amitriptyline and imipramine and their active metabolites nortriptyline and desipramine, respectively, at therapeutic concentrations in human plasma by use of liquid chromatography. The drugs are extracted at pH 10.5 into hexane/isoamyl alcohol, which is evaporated and the resid...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-01-01 00:00:00
abstract::I describe a micro-scale method for determining lead in whole blood by utilizing a graphite furnace. Sample pretreatment consists of fivefold dilution with a dilute surfactant. The method is directly calibrated with lead standards prepared in dilute HNO3. To eliminate a small, nonspecific absorption signal from the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-04-01 00:00:00
abstract::We describe a gas chromatographic method for measuring submicrogram quantities of dianhydrogalactitol, a promising antineoplastic agent (currently undergoing clinical trials in humans), in plasma. The drug is first extracted from blood plasma by saturating the aqueous phase with solid potassium carbonate and extractin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-10-01 00:00:00
abstract::We describe a group of glycoproteins that are synthesized and released by human breast tumors maintained in organ culture and similar glycoproteins released by a human breast carcinoma cell line (BT-20). The electrophoretic mobility of these glycoproteins on cellulose acetate is consistent with increased glycoprotein-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-11-01 00:00:00
abstract:BACKGROUND:Genomic instability resulting in copy number variation is a hallmark of malignant transformation and may be identified through massive parallel sequencing. Tumor-specific cell free DNA (cfDNA) present in serum and plasma provides a real-time, easily accessible surrogate. METHODS:DNA was extracted from serum...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2014.226571
更新日期:2015-01-01 00:00:00
abstract::We present the results of measurements of alkaline phosphatase activity from interlaboratory transferability studies conducted by 12 laboratories in five countries. The variability, as demonstrated by within-day precision (CV less than or equal to 2.6%), between-day precision (CV less than or equal to 3.6%), and betwe...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-05-01 00:00:00
abstract:BACKGROUND:Gradient gel electrophoresis (GGE) and nuclear magnetic resonance (NMR) spectroscopy are both widely accepted methods for measuring LDL and HDL particle size. However, whether or not GGE- or NMR-measured LDL or HDL particle size predicts coronary heart disease (CHD) risk to a similar extent is currently unkn...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.140939
更新日期:2010-05-01 00:00:00
abstract::We measured glucocorticoid receptors (GR) in mononuclear leukocytes (MNL) isolated from peripheral blood of 145 apparently healthy volunteers (86 men and 59 women). An age-related decrease in the number of GR was suggested between subjects younger than 20 years and elderly subjects; there was no apparent seasonal vari...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-10-01 00:00:00