Abstract：
:We have developed a simple, specific, and sensitive reversed-phase liquid-chromatographic method for accurate and simultaneous analysis of corticosterone and cortisol in human plasma. We achieved a detection limit of 300 ng/L for both steroids by modifying the old solid-phase extraction method to make use of "Tef Elutor" C18 columns, using a minibore (100 x 2 mm) analytical column, and using an ultraviolet detector with a 10-mm-pathlength flow cell. With the new extraction method absolute extraction efficiencies were greater than 90% for all the analytes, including the internal standard, flumethasone. The mobile phase was water (containing 5 mL of triethylamine per liter and citric acid to adjust the pH to 6.5), tetrahydrofuran, and acetonitrile (82/10/8 by vol). The average interassay CV for corticosterone at 0-25 micrograms/L was 6.5%; that for cortisol at 0-300 micrograms/L was 3.8%. The analytical recovery relative to the internal standard was 100.2% for cortisol and 102.6% for corticosterone. Possible interferences from drugs and other steroids were studied.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Hariharan M,Naga S,VanNoord T,Kindt EKsubject
Has Abstractpub_date
1992-03-01 00:00:00pages
346-52issue
3eissn
0009-9147issn
1530-8561journal_volume
38pub_type
杂志文章abstract：:HbCO in blood sampled from 20 mothers and newborns immediately after birth was measured with a new, simple gas-chromatographic method for CO. The mean ratio of HbCO to total hemoglobin for 13 non-smoking mothers did not differ significantly from that for their infants (mean 0.38%, SD 0.26% vs 0.38%, SD 0.13%), but the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
abstract：:Parathyroid hormone-related protein (PTHrP) was measured in plasma by a new immunoradiometric assay (IRMA) from Nichols Institute. The assay is specific for PTHrP and shows excellent parallelism when measuring keratinocyte fluid, samples with high PTHrP content, and PTHrP-supplemented plasma. A precision profile estab...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-03-01 00:00:00
abstract：:Three different techniques of lipase (EC 3.1.1.3) determination (titrimetry, nephelometry, and enzyme immunoassay) were used to investigate an interesting effect of ionic strength on enzyme activity. Both activation in the presence of NaCl (140 mmol/L) and strong immunoinhibition were observed for lipase from plasma o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-03-01 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：:Taurine was measured in cerebrospinal fluid by reacting it with fluorescamine to form a fluorescent derivative, followed by separation on a reversed-phase column and fluorometric detection and evaluation. The assay is rapid (17 min) and sensitive to as little as 1 mumol/L. The mean value for 27 cerebrospinal fluid sam...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-08-01 00:00:00
abstract：:We describe a liquid-chromatographic assay for AZT in human plasma and urine. This assay involves the use of two internal standards, allowing reference of AZT peaks to the appropriate internal standard, the choice depending on the range of concentrations encountered. This method is isocratic, specific, sensitive enoug...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
abstract：:In the disposable rotor of the SAM microcentrifugal analyzer, various lyophilized reagents are predistributed in 24 33-microL cuvets, for determination of multiple analytes in one specimen (e.g., for patient profiles). We evaluated a prototype of this system, which can be used at 25, 30, or 37 degrees C; absorbance re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-09-01 00:00:00
abstract：:A continuous-monitoring method for measuring acid phosphatase activity with alpha-naphthyl phosphate as the substrate was critically evaluated and modified. Using partially purified prostatic acid phosphatase, we show that certain conditions for the assay must be satisfied to ensure linearity. These conditions include...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-12-01 00:00:00
abstract：BACKGROUND:Recent reports have described inherent problems with androgen immunoassays compared with mass spectrometry analyses. METHODS:We developed a method for measuring serum testosterone (T) and 5alpha-dihydrotestosterone (DHT) simultaneously via liquid-liquid extraction followed by liquid chromatography-tandem ma...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.103846
更新日期：2008-11-01 00:00:00
abstract：:In assessing interference from bilirubin, the use of a synthetic soluble derivative (ditaurobilirubin, DTB) is recommended as a surrogate for the natural conjugates (Bc). We compared the interference effect of unconjugated bilirubin (Bu), Bc, and DTB, using six mechanized methods for serum creatinine measurement. No s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-02-01 00:00:00
abstract：:We describe a modification of the MacGee method [Anal. Chem. 42, 421 (1970)] for rapid determination of phenytoin (diphenylhydantoin) in plasma by gas-liquid chromatography, in which an ethylaing reagent is used instead of the more common methylating reagents. With this modification, several N-methylated antiepileptic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-05-01 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：BACKGROUND:In vitro and animal studies suggest that tumor necrosis factor alpha (TNF-alpha) modulates intestinal iron transport. We hypothesized that the effect of TNF-alpha might be particularly relevant if iron absorption is not effectively controlled by the HFE gene. METHODS:In patients with homozygous C282Y hemoch...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.065417
更新日期：2006-08-01 00:00:00
abstract：:We describe the development of a stable reference material for prostatic acid phosphatase, derived from human prostatic tissue and human seminal fluid. The enzyme was purified by an L-tartramic acid affinity-chromatography technique. Two-dimensional electrophoresis revealed essentially no contaminating proteins, and s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-08-01 00:00:00
abstract：BACKGROUND:Test repetition could be a readily modifiable component of laboratory utilization. Laboratory test repetition has not been rigorously studied at a population-based level. Our objective was to determine the prevalence of, and charges associated with, repetition of eight common laboratory tests. METHODS:We pe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.021220
更新日期：2003-12-01 00:00:00
abstract：:A new method for the reliable identification of localized variations in DNA by detection of associated diagnostic products with matrix-assisted laser desorption ionization time-of-flight mass spectrometry is described. The diagnostic products are generated by the primer oligo base extension (PROBE) reaction, which req...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
abstract：:We present a comparative evaluation of two commercial kits, the "Quantitope" and "GammaCoat," for radioimmunoassay of digoxin in serum. These kits, in which iodine-125 is used as a label, proved to suitable for digoxin assay as determined by their reproducibility, sensitivity, precision, and a regression analysis. Hem...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-02-01 00:00:00
abstract：BACKGROUND:Aberrant DNA hypermethylation of CpG islands occurs frequently throughout the genome in human colorectal cancer (CRC). A genome-wide DNA hypermethylation analysis technique using circulating cell-free DNA (cfDNA) is attractive for the noninvasive early detection of CRC and discrimination between CRC and othe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2019.301804
更新日期：2019-07-01 00:00:00
abstract：:We compared five ion-selective electrodes (ISEs; AVL 985S, Baxter Lytening 2Z, Beckman EL-ISE, Ciba-Corning 654 Na/K/Li, and Nova CRT 11) and a colorimetric method (Ektachem) for determination of lithium with flame atomic absorption and atomic emission spectroscopy. We evaluated precision, recovery, interference by dr...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
abstract：BACKGROUND:Formalin-fixed paraffin-embedded (FFPE) tumor material represents a valuable resource for the analysis of RNA-based biomarkers, both in research laboratories and in routine clinical testing. A robust and automated RNA-extraction method with a high sample throughput is required. METHODS:We evaluated extracti...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.122572
更新日期：2009-09-01 00:00:00
abstract：:We determined approximately 15,000 laboratory values in 236 individuals between the ages of 60 and 90 y, 22 individuals between 90 and 99 y, and 69 individuals greater than or equal to 100 y, and compared these with values in young adults. We tested 47 different analytes in the 60-90-y group and 93 analytes in the gre...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-06-01 00:00:00
abstract：BACKGROUND:It has been postulated that changes in S-adenosylhomocysteine (AdoHcy), a potent inhibitor of transmethylation, provide a mechanism by which increased homocysteine causes its detrimental effects. We aimed to develop a rapid and sensitive method to measure AdoHcy and its precursor S-adenosylmethionine (AdoMet...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.046995
更新日期：2005-08-01 00:00:00
abstract：BACKGROUND:We evaluated the completeness of reporting of diagnostic test accuracy (DTA) systematic reviews using the recently developed Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA)-DTA guidelines. METHODS:MEDLINE® was searched for DTA systematic reviews published October 2017 to January 2...
journal_title：Clinical chemistry
pub_type： 杂志文章,meta分析
doi：10.1373/clinchem.2018.292987
更新日期：2019-02-01 00:00:00
abstract：BACKGROUND:Lectin-like oxidized LDL receptor 1 (LOX-1) is implicated in atherothrombotic diseases. Activation of LOX-1 in humans can be evaluated by use of the LOX index, obtained by multiplying the circulating concentration of LOX-1 ligands containing apolipoprotein B (LAB) times that of the soluble form of LOX-1 (sLO...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.140707
更新日期：2010-04-01 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：:We report microchromatographic measurement of fetal hemoglobin (HbF) proportions in a 36-year-old African-American multigravida woman. At 34 weeks she delivered a 630-g male infant who subsequently did well. Hemoglobin electrophoresis of the hemolysate revealed nearly 100% HbF without HbA, an extremely unusual natural...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：:We tested the diagnostic sensitivity of various urinary analytes for detecting cadmium-induced nephropathy at an early stage. We investigated 73 healthy persons (control group 1) and individuals exposed to cadmium, either environmentally (n = 36, risk group 2) or occupationally (n = 62, exposed group 3). All data were...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-05-01 00:00:00
abstract：:We describe conditions for determining carboxypeptidase N (EC 3.4.17.3) activity by liquid chromatography. Serum (10 microL) is mixed with the artificial substrates hippuryl-L-arginine (30 mmol/L) and hippuryl-L-lysine (100 mmol/L) in 50 mmol/L 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer solution...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-12-01 00:00:00
abstract：:In this liquid-chromatographic method for the determination of bromide in human serum, an important and unique feature is pre-analysis ultrafiltration of the sample, which effectively removes proteins. The chromatographic system consists of an anion-exchange column (Whatman Partisil SAX 10-micron particles), an isocra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
abstract：BACKGROUND:Mass spectrometric assays could potentially replace protein immunoassays in many applications. Previous studies have demonstrated the utility of liquid chromatography-multiple-reaction monitoring-mass spectrometry (LC-MRM/MS) for the quantification of proteins in biological samples, and many examples of the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.173856
更新日期：2012-04-01 00:00:00
