Abstract：
:A radioimmunoassay for 1,25-dihydroxycholecalciferol which did not cross react with 1,25-dihydroxyergocalciferol is described. IgG fractions were prepared from the serum of rabbits that had been immunized with 1,25-dihydroxycholecalciferol-3-hemisuccinate coupled to bovine albumin. Radioligand binding by the IgG fractions was time-, temperature-, and pH-dependent. The IgG fractions had a high affinity for 1,25-dihydroxycholecalciferol but cross reacted with 25-hydroxycholecalciferol and 24,25-dihydroxycholecalciferol. Vitamin D2 metabolites did not cross react in the assay when amounts up to 9 ng per tube were tested. The determination of 1,25-dihydroxycholecalciferol in human serum required an organic extraction and chromatographic isolation of the metabolite. Radioligand binding was influenced by the presence and concentration of the proteins in the phosphate buffer. The mean concentration of 1,25-dihydroxycholecalciferol in serum from normal adults was 56 (SEM 5.7) ng/L. 1,25-Dihydroxycholecalciferol was not detectable in serum from a nephrectomized subject and the concentration in serum was lower than normal in hypoparathyroid patients. Ingestion of 1,25-dihydroxycholecalciferol by nephrectomized or hypoparathyroid patients restored the concentration of 1,25-dihydroxycholecalciferol in serum to the normal range. The stability of the IgG fraction, the relatively short incubation interval, and the ability to measure 1,25-dihydroxycholecalciferol without interference from 1,25-dihydroxyergocalciferol are unique aspects of this radioimmunoassay.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Gray TK,McAdoo T,Pool D,Lester GE,Williams ME,Jones Gsubject
Has Abstractpub_date
1981-03-01 00:00:00pages
458-63issue
3eissn
0009-9147issn
1530-8561journal_volume
27pub_type
杂志文章abstract：BACKGROUND:Apolipoprotein (apo) E is a component of two major classes of plasma lipoproteins, apo B- (apo E-LpB) and non-apo B-containing (apo E-Lp-non-B) lipoproteins. The factors that affect total apo E in particles [lipoprotein E (LpE), apo E-Lp-non-B, and apo E-LpB], are incompletely characterized. METHODS:We stud...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-02-01 00:00:00
abstract：:We describe a competitive enzyme immunoassay, the ExtrAvidin-biotin system, for determining osteocalcin in human serum or plasma. Antibodies were raised against bovine osteocalcin. Binding of the antibodies to osteocalcin was calcium-dependent. Limit of detection is 0.07 nmol/L (0.4 microgram/L). The standard curve fo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-10-01 00:00:00
abstract：:We measured the cross reactivity of two medications--digitoxin and spironolactone--in two digoxin radioimmunoassay (liquid and solid-phase) kit procedures. Both tests showed similar average percentages of cross reactivity with digitoxin (7.2 and 8.9% for intravenous, and 11.9 and 10.9% for oral administration), but no...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-04-01 00:00:00
abstract：:We used a modification of the polymerase chain reaction (PCR), involving two pairs of oligonucleotide primers, to detect a mutation in the low-density lipoprotein (LDL) receptor gene, commonly occurring among patients with familial hypercholesterolemia (FH) in Finland. This mutation, called FH-Helsinki, involves a lar...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-06-01 00:00:00
abstract：BACKGROUND:The European Atherosclerosis Society-European Federation of Clinical Chemistry and Laboratory Medicine Consensus Panel aims to provide recommendations to optimize atherogenic lipoprotein quantification for cardiovascular risk management. CONTENT:We critically examined LDL cholesterol, non-HDL cholesterol, a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2018.287037
更新日期：2018-07-01 00:00:00
abstract：BACKGROUND:Late enhancement MRI (LE-MRI) and cardiac troponin I (cTnI) are sensitive methods to detect subclinical myocardial injury. We sought to investigate the relation between plasma concentrations of cTnI measured with a high-sensitivity assay (hs-cTnI) and the development of unrecognized myocardial infarctions (U...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
doi：10.1373/clinchem.2014.222430
更新日期：2014-10-01 00:00:00
abstract：:In this study we determined the prevalence of autoantibodies against casein kinase II (CKII) in patients positive for anti-70K marker antibodies, which is indicative of mixed connective tissue disease. An anti-CKII ELISA was established with the use of bacterially expressed recombinant CKII proteins. Eight out of 52 a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-12-01 00:00:00
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
abstract：:We directly estimated plasma aldosterone radioimmunologically with use of an antiserum raised against an aldosterone-3-oxime/bovine serum albumin conjugate, the estimation being on samples with and without heating (60 degrees C), and diluted and undiluted. Values so obtained were compared with those by radioimmunoassa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-01-01 00:00:00
abstract：:A patient who ingested a methanol/nitromethane mixture (model airplane fuel) showed an apparent plasma creatinine concentration of 8.0 mmol/L by the Jaffé reaction when the actual creatinine concentration, as measured by a specific enzymatic method, was 0.09 mmol/L. This effect was due to nitromethane in the plasma. I...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
abstract：INTRODUCTION:Parathyroid hormone-related peptide (PTHrP) is involved in activating pathways, allowing tumor cells to form bone metastases. Measurement of PTHrP is used for the diagnosis and clinical management of patients suspected of hypercalcemia of malignancy. We developed an LC-MS/MS method for measuring PTHrP, est...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2015.244012
更新日期：2016-01-01 00:00:00
abstract：BACKGROUND:The antiphospholipid syndrome (APS) is an important cause of acquired thromboembolic complications and pregnancy morbidity. Its diagnosis is based on clinical and laboratory criteria, defined by strict guidelines. The original clinical and laboratory criteria for the identification of APS patients were publi...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2009.133678
更新日期：2010-06-01 00:00:00
abstract：BACKGROUND:The multiple endocrine neoplasia 2 (MEN 2) syndromes [MEN 2A, MEN 2B, and familial medullary thyroid carcinoma (FMTC)] are caused by germline mutations of the RET protooncogene. Because 85% of MEN 2A patients and 30% of FMTC patients have mutations at codon 634, the recommended molecular analyses begin at ex...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
abstract：BACKGROUND:We explored the utility of multiplexed temperature gradient capillary electrophoresis (TGCE) as a screening tool for identifying genetic changes in the human mitochondrial genome. We examined changes in mitochondrial DNA (mtDNA) in nonmelanoma skin cancers (NMSCs), using TGCE to resolve genetic differences c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.040311
更新日期：2005-02-01 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
abstract：:Four assay procedures for tobramycin in serum--enzyme immunoassay (I), substrate-labeled fluorescent immunoassay (II), radioimmunoassay (III), and bioassay (IV)--were compared and evaluated by replicate and analytical recovery studies. I and II were about 50% more precise than III and IV. II was substantially more nea...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：:We combined the amplification refractory mutation system (ARMS) and fluorescence polarization (FP) to give a homogeneous genomic DNA genotype analysis method. Oligonucleotide probes labeled with the fluorescein dyes fluorescein isothiocyanate and 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein and the rhodamine dye 6-c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-08-01 00:00:00
abstract：BACKGROUND:Galectin-3 has emerged as a potential useful novel biomarker for heart failure and cardiovascular disease (CVD). However, it remains unclear whether galectin-3 is associated with recurrent cardiovascular events during long-term follow-up of patients with stable coronary heart disease (CHD) after adjustment f...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.257550
更新日期：2016-10-01 00:00:00
abstract：BACKGROUND:Recent recognition of its broad pathophysiological importance has triggered an increased interest in 25-hydroxyvitamin D [25(OH)D]. By consequence, throughput in 25(OH)D testing has become an issue for clinical laboratories, and several automated assays for measurement of 25(OH)D are now available. The aim o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.176545
更新日期：2012-03-01 00:00:00
abstract：:Quinidine in serum was measured at 330 nm, after protein precipitation, with an alkyl phenyl reversed-phase chromatographic column by peak-height determination (external standards.) Sensitivity was 0.3 mg/liter, with linear response to at least 10 mg/liter serum. Interassay precision, measured on 20 consecutive days, ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
abstract：BACKGROUND:Quantitative, miniaturized nucleic acid assays and immunoassays can be developed with single microparticles, microfluorometric detection, and intrinsically fluorescent lanthanide chelates in a multiple assay format to decrease reagent consumption, cost, and assay time. We used recombinant Fab fragments to ca...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-11-01 00:00:00
abstract：:We describe a new method for quantitatively measuring substances of clinical interest by high-performance liquid affinity chromatography (HPLAC). As a model system we selected analysis for transferrin in human serum with immobilized antibodies in a high-performance liquid chromatographic system. SelectiSpher-10 Activa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-10-01 00:00:00
abstract：:We describe an enzyme-linked immunosorbent assay for determination of light-chain ratios for IgG, IgA, and IgM in serum. A commercial serum with known overall kappa and lambda concentrations was used as standard. To capture the respective immunoglobulins, we used antibodies to gamma, lambda and mu chains coated onto m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:We investigated the efficiency, accuracy, and reliability of the ultrafiltration/dipstick methodology commonly used to diagnose myoglobinuria. Twenty-five myoglobin-containing urine specimens were filtered by centrifugation for 15 min at 1500g through a Centricon-30 membrane filter. Both the original specimen and filt...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:It has been hypothesized over many years that the autoimmune endocrine diseases are each due to antigen-specific defects in suppressor (regulatory) T lymphocyte function. There is now increasing evidence in studies of autoimmune thyroid disease and insulin-dependent diabetes mellitus that suppressor cells are activate...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1994-11-01 00:00:00
abstract：BACKGROUND:Increased concentrations of cell-free DNA have been found in several disorders and have been interpreted as evidence of increased rates of cell death or turnover. Evidence from in vitro and animal experiments suggests that DNA may play a role in the pathogenesis of rheumatoid arthritis (RA). METHODS:We meas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.084509
更新日期：2007-09-01 00:00:00
abstract：:We examined the relationship between analytical sensitivity, precision at the lower limit of the reference interval, and diagnostic performance in hyperthyroidism for one radioimmunoassay and five immunometric assay kits for thyrotropin. The analytical sensitivity of these kits extended from 0.05 to 1.56 milli-int. un...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-07-01 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：:For many lysosomal storage disorders, presymptomatic detection, before the onset of irreversible pathology, will greatly improve the efficacy of current and proposed therapies. In the absence of a family history, presymptomatic detection can be achieved only by a comprehensive newborn screening program. Recently we re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-10-01 00:00:00
abstract：:Sensitivity, stability, and specificity of the color-producing reaction of hydrogen peroxide with bezidine, leuco-malachite green, or o-dianisidine were tested in numerous systems containing hemoglobin and other hemoproteins. Use of urea or low temperature (to minus 12 degrees C), or both, was highly beneficial, espec...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
