Abstract：
:We describe the process of certification for a gamma-glutamyltransferase reference material (CRM no. 319). Fifteen laboratories participated to this interlaboratory evaluation. All steps of the measurements were controlled in an effort to locate potential sources of variations. In particular, the exclusion of some data was strictly documented or justified by the non-observance of the IFCC method and (or) discrepancies in instrumentation, reconstitution of the lyophilized samples, or measurement technique. Inaccuracy in the reconstitution of the lyophilized material was +/- 0.68%, and the molar absorptivity of the 5-amino-2-nitrobenzoate reported by each laboratory was within +/- 2% limits of the value reported by the IFCC. Calculated from the sets of accepted results, the total CV among samples was 2.6% and the overall CV was 3.2%. Within-day and between-day CVs were 1.1% and 1.4%, respectively. The greatest variation for a single component was the between-laboratory variability (CV 3.1%); the within-laboratory CV, including the day effect, was 1.8%. Finally, the certified value for the catalytic concentration of this enzyme in the reconstituted lyophilized reference material was 86.8 U/L with an uncertainty of +/- 2.1 U/L (0.95 confidence interval). The uncertainty appeared to be compatible with the end-use of this reference material.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Schiele F,Muller J,Colinet E,Siest Gsubject
Has Abstractpub_date
1987-11-01 00:00:00pages
1978-82issue
11eissn
0009-9147issn
1530-8561journal_volume
33pub_type
杂志文章abstract：BACKGROUND:Bilirubin has antioxidative and cytoprotective properties. Low plasma concentrations of bilirubin are reportedly associated with the development of coronary and cerebrovascular disease, and bilirubin concentrations are strongly correlated with the enzyme activity of the hepatic uridine diphosphate glucuronos...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2007.102046
更新日期：2008-05-01 00:00:00
abstract：:Ion chromatography is a new analytical technique in which the ions to be analyzed are separated on a special pellicular ion-exchange column. Once separated, the effluent from the separating column passes into a second ion-exchange column, which removes the eluent or buffer ions from the moving phase without removing t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-09-01 00:00:00
abstract：:Urinary polyamines were measured by a fluorometric thin-layer chromatographic technique in samples collected daily throughout a single menstrual cycle by each of 13 healthy women. Polyamine excretion fluctuated considerably, but excretion of putrescine, spermidine, and spermine combined was consistently greatest durin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-05-01 00:00:00
abstract：:We describe a novel assay for measuring glycohemoglobin directly from anticoagulated whole blood with the Abbott IMx analyzer. The glycohemoglobin is labeled with a soluble polyanionic affinity reagent and the anionic complex is then captured with a cationic solid-phase matrix. Glycohemoglobin is quantified by measuri...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-10-01 00:00:00
abstract：BACKGROUND:Identifying novel risk markers in cardiovascular patients remains a research priority. Longer follow-up generally is considered favorable in such studies, but associations of interest may become attenuated with increasing follow-up. This issue has not been adequately addressed in the context of patient cohor...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.263202
更新日期：2017-03-01 00:00:00
abstract：:The ultraviolet fluorescence emission spectra of sera from apparently healthy persons and of sera from cancer patients frequently show significantly different curve shapes. A biparametric fluorescence method has been developed to use these deviations to detect patients with malignant diseases (Clin Chem 1986;32:1974-8...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-11-01 00:00:00
abstract：:We measured advanced glycosylation end products in the mesenteric artery of 37 patients (ages 29-82 years), 34 of whom were nondiabetic. Samples of arterial tissue were obtained during bowel resectioning. Advanced glycosylation end products were measured as collagen-linked fluorescence (excitation wavelength 370 nm, e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-04-01 00:00:00
abstract：:A modified pentamer formation assay (PFA) for quantification of tacrolimus and active metabolites after extraction from whole blood is described. The lower limit of detection was 2 microg/L. Intraassay precision (CV) was 5.7-13.7%, and the interassay CV was 6. 1-14.9%. Tacrolimus trough concentrations in 104 whole blo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-12-01 00:00:00
abstract：:We detected increased concentrations of lipoperoxidation products, as malondialdehyde, in the serum of an infant with classic hemolytic-uremic syndrome. The concentrations declined when peritoneal dialysis was initiated and eventually returned to normal after clinical recovery. Our observation adds to the existing bod...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-11-01 00:00:00
abstract：:6-thioguanine (6-TGN) and methyl 6-mercaptopurine nucleotides (Me6-MPNs) are the two major metabolites found in erythrocytes after administration of azathioprine. In an attempt to understand the role of these metabolites in the pharmacologic and toxic activity of thiopurines, we have developed a HPLC method for the si...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
abstract：BACKGROUND:Determinations of certain forms of prostate-specific antigen (PSA) have been shown to increase the specificity for prostate cancer (PCa). One such variant, proteolytically active PSA, is a potentially useful tumor marker, but it is not specifically recognized by antibodies. Using phage display libraries, we ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.026146
更新日期：2004-01-01 00:00:00
abstract：:The characteristics of the Abbott selective fluorescence polarization immunoassay for cyclosporine in whole blood (TDXSP) were compared with the Incstar radioimmunoassay by using kit standards (INCSP) or TDXSP standards (INCTDX) with samples from adult (48) and pediatric (24) liver-transplant recipients and a further ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-01-01 00:00:00
abstract：:Comparison of two methods for determining a substance is a common procedure in clinical chemistry. Almost without exception, normal theory statistics are used with the tacit assumption that the data under test show gaussian distributions. Experience has led us to question this assumption for populations of differences...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
abstract：BACKGROUND:Human iron status is influenced by environmental and genetic factors. We hypothesized that the genetic polymorphism of haptoglobin (Hp), a hemoglobin-binding plasma protein, could affect iron status. METHODS:Reference values of serum iron status markers were compared according to Hp phenotypes (Hp 1-1, Hp 2...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-10-01 00:00:00
abstract：:Haptoglobin is a hemoglobin-binding protein expressed by a genetic polymorphism as three major phenotypes: 1-1, 2-1, and 2-2. Most attention has been paid to determining haptoglobin phenotype as a genetic fingerprint used in forensic medicine. More recently, several functional differences between haptoglobin phenotype...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1996-10-01 00:00:00
abstract：:We compared three radioligands for use in a cytoplasmic estrogen-receptor assay, using pooled cytosol from human breast adenocarcinomas. The estrogen receptor content was determined in vitro by a dextran-coated charcoal method involving a 4-h incubation with and without diethylstilbestrol. Tritiated moxestrol failed t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-03-01 00:00:00
abstract：:We describe a gas-chromatographic method for measuring chlorpromazine and its metabolites chlorpromazine sulfoxide, mono-N-desmethylchlorpromazine, and di-N-desmethylchlorpromazine at therapeutic concentrations in human serum, with use of a nitrogen detector. The compounds are extracted from serum at pH 10.5 into hexa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-07-01 00:00:00
abstract：:We examined the changes in sensitivity and specificity that would occur with alterations in the sample-collection schedule and (or) cutoff criterion for the increase in hydrogen concentration in breath after administration of doses of lactose in the dietary range. In a breath-analysis test to classify individuals as l...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:Applying the principles of chemometrics can lead to development of a powerful, simple, comprehensive system for characterizing measurement reliability of analytical processes. The system described here consists of a format for specifications, definitions, and decision rules for evaluating and comparing analytical proc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
abstract：:Determination of the MB isoenzyme of creatine kinase in patients with acute myocardial infarction may be disturbed by the presence of macro creatine kinase. The relative molecular mass of this form of creatine kinase in human serum is at least threefold that of the ordinary enzyme, and it is more thermostable. Here we...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：:Circulating prostate cells can be detected in cancer patients by using reverse transcriptase-PCR (RT-PCR) assay for prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSM) mRNA. A quality-control study involving a conventional RT-PCR assay was performed and, surprisingly, detected both transcripts...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
abstract：BACKGROUND:Sensitive and specific biomarkers for the early detection of esophageal squamous cell carcinoma (ESCC) are urgently needed to reduce the high morbidity and mortality of the disease. The discovery of serum microRNAs (miRNAs) and their unique concentration profiles in patients with various diseases makes them ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.147553
更新日期：2010-12-01 00:00:00
abstract：BACKGROUND:Newborn screening for deficiency in the lysosomal enzymes that cause Fabry, Gaucher, Krabbe, Niemann-Pick A/B, and Pompe diseases is warranted because treatment for these syndromes is now available or anticipated in the near feature. We describe a multiplex screening method for all five lysosomal enzymes tha...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.035907
更新日期：2004-10-01 00:00:00
abstract：BACKGROUND:Disease-defining chromosomal translocations are seen in various neoplasms, especially in lymphomas and leukemias. Translocation detection at the DNA level is often complicated by chromosomal breakpoints that are distributed over very large regions. We have developed a ligation-based assay [the looped ligatio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.270140
更新日期：2017-07-01 00:00:00
abstract：:A new computer-interfaced system of general applicability in the clinical laboratory has been built. The system is constructed around a new type multicuvette. Quantitation is currently by spectrophotometry and is on-line, with use of a mini-computer with output going to an electrostatic printer/plotter. The system can...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-08-01 00:00:00
abstract：BACKGROUND:A substantial proportion of the variability in the absorption and clearance of cyclosporin A (CsA) after oral administration has been attributed to variability in liver cytochrome P-450 3A4 (CYP3A4) activity and intestinal P-glycoprotein (P-gp) concentration. A polymorphism in the CYP3A4 promoter region, ter...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-06-01 00:00:00
abstract：:Assays with different specificity are used for cyclosporin monitoring in clinical transplantation. A recent survey of 35 centers showed that 86% used immunoassays for cyclosporin A (CsA). In consensus documents the following performance criteria were recommended: (a) imprecision < or = 10% at 50 microg/L and < or = 5%...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-10-01 00:00:00
abstract：BACKGROUND:Prostate-specific antigen (PSA) occurs in serum both free and in complex with protease inhibitors. The complex with alpha1-antichymotrypsin (ACT) is the major form in serum, and the proportion of PSA-ACT is higher in prostate cancer (PCa) than in benign prostatic hyperplasia (BPH). PSA also forms a complex w...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：1999-06-01 00:00:00
abstract：:Of 98 patients' specimens examined for alkaline phosphatase (EC 3.1.3.1) isoenzymes by electrophoresis on cellulose acetate membrane after incubation with neuraminidase, 50 showed only a single liver or bone isoenzyme staining band; in 15 of these, the tissue origin of the fraction could not be accurately identified f...
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
