Abstract:
:A quantitative "high-performance" liquid-chromatographic method is described for determining porphyrins in human urine. Porphyrinogens in urine are first converted to the corresponding porphyrins by oxidation with iodine. Uroporphyrin, hepatacarboxylic acid porphyrin, hexacarboxylic acid porphyrin, pentacarboxylic acid porphyrin, and coproporphyrin I and III isomers are then separated on a reversed-phase column and measured by fluorometry. Analysis for the six porphyrins is complete within 24 min, including reconditioning for the next sample. The detection limit (twice the signal/noise ratio) for each porphyrin was 1 nmol/L for urine (25 fmol per 50-microL injection). Mean analytical recovery of each porphyrin ranged from 85% to 91%, within-day CVs from 1.4% to 7.3%. Normal reference intervals for porphyrins were established by assaying urine samples from 75 healthy subjects. Significant sex-related differences in coproporphyrin I and III isomers were evident when the values were expressed as nanomoles per gram of creatinine. Coproporphyrin isomer ratio was estimated for utility in the diagnosis of porphyrinurias.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Abe K,Konaka Rsubject
Has Abstractpub_date
1989-08-01 00:00:00pages
1619-22issue
8eissn
0009-9147issn
1530-8561journal_volume
35pub_type
杂志文章abstract::We compared the performance of an automated assay of creatine kinase MB isoenzyme (CK-MB) mass (Stratus) with that of a CK-MB enzymatic assay routinely used at our institutions. Both of these assays use the same CK-MB-specific monoclonal antibody to immunocapture CK-MB, thus providing a direct means of comparing a mas...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-10-01 00:00:00
abstract::A new, highly sensitive immunoradiometric thyrotropin (TSH) assay involving solid-phase-coupled monoclonal antibodies (Boots-Celltech Sucrosep IRMA-TSH) has been evaluated in a wide variety of patients with thyroidal and nonthyroidal illnesses and the results compared with those obtained by conventional diagnostic TSH...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.128678
更新日期:2009-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.194217
更新日期:2013-06-01 00:00:00
abstract::Autocorrelation of clinical chemistry quality-control (Q/C) measurements causes one of the basic assumptions underlying the use of Levey-Jennings control charts to be violated and performance to be degraded. This is the requirement that the observations be statistically independent. We present a proposal for a new app...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-07-01 00:00:00
abstract::Detection of intracellular antigens by flow cytometry requires effective fixation and permeabilization of the cell membrane. This study compares three fixation/permeabilization techniques: two commercial chemical reagents, the ORTHOPermeaFix (OPF) and the FIX&PERM Cell Permeabilization Kit (F&P), and a novel method ba...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract::We determined fluoxetine (Prozac) and its major metabolite norfluoxetine in plasma by liquid chromatography with fluorescence detection. After liquid-liquid extraction from 1 mL of plasma, the extract was derivatized at room temperature with dansyl chloride, and the highly fluorescent derivatives were chromatographed ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::A rapid (30-min) semiautomated continuous-flow procedure is described for use in assessing the phospholipids of the particulate ("lamellar body") fraction of human amniotic fluid. The method is based on measuring the difference in fluorescence of 1,6,-diphenyl-1,3,5-hexatriene added to amniotic fluid before and after ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-02-01 00:00:00
abstract:BACKGROUND:Age-adjusted morbidity and mortality rates from coronary heart disease (CHD) are higher in men than in women. Androgens are suspected to be responsible for the male disadvantage. The genomic effect of androgens is mediated by the androgen receptor (AR), which has a polymorphic CAG repeat in exon 1. The numbe...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2005.049262
更新日期:2005-07-01 00:00:00
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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::We compare measurement of total fast hemoglobin (HbA1) by "high-performance" liquid chromatography and by electrophoresis on agar gel. Blood samples were obtained from a diverse population (n = 222): offspring of two diabetic parents, diabetic patients with and without retinopathy, diabetic and non-diabetic pregnant w...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-03-01 00:00:00
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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
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.023341
更新日期:2003-11-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 历史文章,杂志文章
doi:
更新日期:2000-07-01 00:00:00
abstract:BACKGROUND:Diagnosis of mitochondrial disorders usually requires a muscle biopsy to examine mitochondrial function. We describe our diagnostic procedure and results for 29 patients with mitochondrial disorders. METHODS:Muscle biopsies were from 43 healthy individuals and 29 patients with defects in one of the oxidativ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.062414
更新日期:2006-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-09-01 00:00:00
abstract::As the domain of monitoring therapeutic drugs rapidly expands from experimental investigations to everyday patient care, all clinical laboratory scientists, but especially clinical chemists, must learn to deal with their involvement in this expansion. First, the theoretical concepts underlying clinical pharmacology mu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-09-01 00:00:00
abstract::We compared the results obtained by a micromethod for the determination of plasma lipoprotein cholesterol, in which electrophoresis is used to separate the lipoprotein fractions (beta-, pre-beta-, and alpha-lipoproteins), with those determinations with ultracentrifugation (low-density, very-low-density, and high-densi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-10-01 00:00:00
abstract::Major depression is one of the most common clinical problems seen by primary-care physicians. The prevalence is 5% to 10% in primary-care outpatients and 15% in medically ill inpatients. Despite this high prevalence rate, depression is frequently not accurately diagnosed. Evidence suggests that misdiagnosis often occu...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1988-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-07-01 00:00:00
abstract::Serum free thyroxin (FT4) was determined in 40 patients with various nonthyroidal illnesses. We studied seven methods: (1) a free thyroxin index calculated from total T4 and triiodothyronine resin uptake; (2) a free T4 index determined by enzyme inhibitor assays (Abbott's "Tetrazyme" and "Thyrozyme"); (3) a free T4 in...
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:1982-01-01 00:00:00