Abstract:
:Measurement of serum ascorbate may be useful in long-term population studies because of the possible influence of ascorbate on numerous physiological factors. We describe an automated method for determining ascorbate in serum and urine by using the reduction of ferric iron by ascorbate and the formation of a color between the resulting ferrous iron and Ferrozine [3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine]. A centrifugal analyzer is used to rapidly and simultaneously measure ascorbate in the samples and standards and minimize interference from slower reacting substances in the sample. The method is highly precise and specific. Data are also presented on the stability of ascorbate in serum, urine, and aqueous solutions.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Butts WC,Mulvihill HJsubject
Has Abstractpub_date
1975-09-01 00:00:00pages
1493-7issue
10eissn
0009-9147issn
1530-8561journal_volume
21pub_type
杂志文章abstract::The difference in absorbance (delta A) between equimolar acid and alkaline solutions of methyl red, at a wavelength near the isosbestic point of the indicator, is reproducible. Furthermore, this delta A is sensitive to changes in the wavelength calibration of the instrument used to make the measurement. The delta A of...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-01-01 00:00:00
abstract::Use of immunoassays that do not detect endogenous digoxin-like immunoreactive factors (DLIF) in serum significantly improves the between-assay correlation of digoxin results for patients. We investigated five different immunoassay methods (Abbott, Clinical Assays, Corning, Du Pont, and Syva), measuring digoxin by all ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-06-01 00:00:00
abstract::We evaluated a new, simple, enzymatic kinetic method from Wako Chemicals GmbH in comparison with a kinetic Jaffé method by using isotope dilution-mass spectrometry (ID-MS) as a reference method. An ID-MS-calibrated serum standard was used. Both the enzymatic and the Jaffé method correlated well with ID-MS, except for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract:BACKGROUND:MALDI-TOF mass spectrometry (MS) is set to make inroads into clinical chemistry because it offers advantages over other analytical platforms. These advantages include low acquisition and operating costs, ease of use, ruggedness, and high throughput. When coupled with innovative front-end strategies and appli...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2015.239491
更新日期:2016-01-01 00:00:00
abstract::We have developed an interactive statistical quality-control system for the small- to medium-sized radioimmunoassay laboratory, which can be used in a programmable desk-top calculator instead of the medium- or large-scale computer systems usually required. The design of this quality-control system is modeled after the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-07-01 00:00:00
abstract:BACKGROUND:Myeloperoxidase (MPO) is a biomarker of inflammation and oxidative stress produced by neutrophils, monocytes, and endothelial cells. Concentrations of MPO predict mortality in patients with chronic heart failure. This study sought to investigate the diagnostic accuracy and prognostic value of MPO in patients...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.142257
更新日期:2010-06-01 00:00:00
abstract:BACKGROUND:Mucopolysaccharidosis type II (MPS II) is a lysosomal storage disorder related to a deficiency in the enzyme iduronate-2-sulfatase (IDS). Clinical trials of enzyme replacement therapy are in progress, but effective treatment will require screening assays to enable early detection and diagnosis of MPS II. Our...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.061838
更新日期:2006-04-01 00:00:00
abstract::A new method for quantifying specific amino acids in small volumes of plasma and whole blood has been developed. Based on isotope-dilution tandem mass spectrometry, the method takes only a few minutes to perform and requires minimal sample preparation. The accurate assay of both phenylalanine and tyrosine in dried blo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-01-01 00:00:00
abstract::The location of the Reference Value for an analyte within the population distribution affects the magnitude of error due to methodological bias. Using the gaussian distribution, we evaluated the effects of systematic and proportional biases of the method (positive and negative), mean value, and standard deviation on t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-11-01 00:00:00
abstract::The diagnosis of thyroid disease now often can be achieved reliably by measuring thyrotropin (TSH) alone. Thyroxine (T4), triiodothyronine, and other analytes are only needed if TSH and the accompanying clinical condition are discordant. We describe here work that confirms the age independence of TSH in both inpatient...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-11-01 00:00:00
abstract::This enzyme immunoassay procedure for pregnancy-associated plasma protein type A involves a "sandwich"-type system in microtitration plates. One can detect 0.27 mg of the protein per liter of serum, with a between-batch CV of 10.2%, and the antiserum used does not cross react with any of the other placentally derived ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
abstract::The formal definition of sensitivity associates the term with the change in the response of a system for a small change of the stimulus causing the response, i.e., the ratio of the response of a system to the stimulus causing it. One interpretation of sensitivity associates the rate of change of the response for a sma...
journal_title:Clinical chemistry
pub_type: 评论,杂志文章
doi:
更新日期:1997-10-01 00:00:00
abstract:BACKGROUND:Efforts have been undertaken recently to assess the fetal genome through analysis of circulating cell-free (ccf) fetal DNA obtained from maternal plasma. Sequencing analysis of such ccf DNA has been shown to enable accurate prenatal detection of fetal aneuploidies, including trisomies of chromosomes 21, 18, ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.180794
更新日期:2012-07-01 00:00:00
abstract::We evaluated the analytical performance of Trinder's glucose oxidase (EC 1.1.3.4)/peroxidase (EC 1.11.1.7) 4-aminophenazone-phenol method for the quantification of serum glucose as adapted to the Technicon SMAC. Our results correlated well with those by the routine SMAC glucose oxidase/peroxidase 3-methyl-2-benzothiaz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-10-01 00:00:00
abstract::o-Phthaldialdehdye reagent was used in assaying urea with a miniature centrifugal analyzer. Seventeen samples can be assayed kinetically in 2 min at a current cost of less than a penny per test. The reaction is initiated in the instrument upon simultaneous mixing of the o-phthaldialdehyde reagent containing 10 microli...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-12-01 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::In this automated system for assaying guanidino compounds, the compounds are resolved on an ion-exchange (Dowex 50) column, then reacted with phenanthrenequinone in alkaline solution. This mixture is then acidified and the resulting fluorescence is measured (lambda ex, 305 nm; lambda em, 395 nm). I applied the system ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-02-01 00:00:00
abstract::We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 00:00:00
abstract::A new type of multilayer film analytical element--consisting of a spreading layer, a blocking layer, an enzymic reagent layer, and a transparent layer--has been developed for blood glucose determination. After a spot of whole blood is dropped on the film, the plasma glucose concentration is determined in 6 min without...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-07-01 00:00:00
abstract::We report a survey on urine drug testing within a total of 269 laboratories of the European Union. Clinical laboratories predominated over forensic laboratories (59.5% vs 28.5%). Screening without identification/quantification was the common approach used by clinical laboratories, whereas screening with identification...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-04-01 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 compared three current methods (immunoinhibition, "Isomune-CK" immunoprecipitation, and the Tandem-E CKMB II immunoenzymometric assay) for determination of creatine kinase (CK; EC 2.7.3.2) isoenzyme MB in serum. Although results inter-correlated well, the immunoinhibition assay gave higher activity values. Atypical...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::We present a statistical interpretation of plasma (Pl) and (or) erythrocyte (Erc) concentrations of magnesium, zinc, calcium, potassium, and total high-density lipoprotein (HDL) cholesterol, as well as of the activity of total creatine kinase (CK) and its CK-MB isoenzyme, in 26 men with pre-infarction syndrome (PIS) a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract::Cardiac troponin I (cTnI) is a regulatory protein unique to myocardium. We used a cardiospecific 30-min ELISA to measure cTnI in EDTA-plasma samples serially drawn from 28 patients before and after coronary artery bypass grafting (CABG)--26 elective and 2 salvage cases. The cTnI increase in 22 of the elective CABG pat...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-11-01 00:00:00
abstract::The enzymatic determination of serum uric acid by use of uricase, catalase, and aldehyde dehydrogenase according to Haeckel [J. Clin. Chem. Clin Biochem. 14, 101 (1976)] showed interferences from ethanol-converting enzymes, which are present in some patients' sera. We have identified these enzymes as alcohol dehydroge...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00
abstract::A triclonal gammopathy is an immunoglobulin abnormality in which three discrete monoclonal subpopulations of immunoglobulin molecules are present in a patient's serum. Monoclonal and biclonal gammopathies have been studied extensively, but relatively little is known about the much rarer triclonal gammopathies. The cas...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-01-01 00:00:00
abstract:BACKGROUND:Increasing numbers of patients are presenting worldwide to emergency departments with suspected myocardial infarction. The use of point-of-care troponin assays might enable faster decision-making in this high-risk population and reduce the burden on emergency facilities. Here, we evaluate the diagnostic perf...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2019.307405
更新日期:2019-12-01 00:00:00
abstract:BACKGROUND:Cardiac troponin T (cTnT) is the preferred biomarker for the diagnosis of acute myocardial infarction (AMI). It has been suggested that cTnT is present predominantly in fragmented forms in human serum following AMI. In this study, we have used a targeted mass spectrometry assay and epitope mapping using West...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.261511
更新日期:2017-02-01 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::We describe a convenient, economical procedure for measuring uroporphyrinogen I synthase (EC 4.3 1.8) activity in erythrocytes, the results of which can be used to diagnose acute intermittent porphyria, in either its latent or acute stage. By limiting the test reaction sequence to the conversion of porphobilinogen to ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-07-01 00:00:00