Abstract:
:Using 123 specimens, we compared the concordance of three different methods for determining glycohemoglobin (GHb): the Diamat (Bio-Rad Laboratories), an automated analyzer measuring HbA1c by cation-exchange chromatography; an assay with the IMx analyzer (Abbott Laboratories), based on boronate affinity binding; and an HPLC method measuring HbA1c by cation-exchange chromatography on a PolyCAT A column (PolyLC Inc.). The Pearson's correlation coefficient between PolyCAT A and Diamat was 0.900 +/- 0.038 (mean +/- 2 SD) and between PolyCAT A and IMx, 0.857 +/- 0.042. However, up to twofold differences were seen in some samples. The proportion of GHb was consistently lower with the PolyCAT A method than with the other two assays, apparently because of better separation of HbA1c from nonglycated coeluting forms of Hb. The difference in glycation percentage between the PolyCAT A and Diamat methods is 2-3% over the whole concentration range. These results point to the limitations of Diamat as a reference method to be used to calibrate other methods for determining HbA1c. Further, a switch from one method to another is likely to cause considerable problems in the clinical follow-up of certain patients.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Turpeinen U,Karjalainen U,Stenman UHsubject
Has Abstractpub_date
1995-02-01 00:00:00pages
191-5issue
2eissn
0009-9147issn
1530-8561journal_volume
41pub_type
杂志文章abstract::Like any other medical technology or intervention, diagnostic tests should be thoroughly evaluated before their introduction into daily practice. Increasingly, decision makers, physicians, and other users of diagnostic tests request more than simple measures of a test's analytical or technical performance and diagnost...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2012.182576
更新日期:2012-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-06-01 00:00:00
abstract:BACKGROUND:In recent years, a large number of studies have been published on the performance of glucose monitors. The quality of these reports is not known. METHODS:We searched the PubMed database for performance evaluations of handheld glucose monitors published from August 2002 to November 2006. Relevant articles we...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2006.083493
更新日期:2007-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1991-08-01 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::A patient with the hyperviscosity syndrome exhibited very high concentrations of intermediate to small circulating immune complexes (CIC), involving 40-50% of the IgG present, with IgG rheumatoid factor activity. We demonstrate that precipitation of CIC by polyethylene glycol in the reaction mixture caused interferenc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-04-01 00:00:00
abstract:BACKGROUND:Plasma creatinine concentration and calculated creatinine clearance are of limited value as glomerular filtration rate (GFR) markers in patients with decompensated liver cirrhosis. We assessed plasma cystatin C as an indicator of GFR in such patients. METHODS:We studied 36 patients with decompensated liver ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.6.935
更新日期:2003-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.107508
更新日期:2008-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.140202
更新日期:2010-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa287
更新日期:2021-01-08 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-10-01 00:00:00
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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
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-07-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-02-01 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
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::A "sandwich" enzyme immunoassay for ferritin in human serum is described, in which horseradish peroxidase-labeled antibody and a very sensitive chromogen, 2,2'-azino-di(3-ethyl-benzthiazolin-6-sulfonate), are used. The solid phase is polypropylene test tubes treated with glutaraldehyde; immunologic reactions are devel...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-04-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1999-10-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.111245
更新日期:2009-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-05-01 00:00:00