Abstract：
:The basic theory of thyroxin-analog-based radioimmunoassays for free thyroxin has been extended to evaluate definitively the effects arising from residual binding of the tracer analog to serum proteins. Using experimentally determined binding constants and computer simulation techniques, we studied the effects of thyroxin-analog binding to serum proteins on results of Amerlex FT4 radioimmunoassay, using this improved mathematical model. Results from computer-simulation studies were compared both directly with in vitro experimental results and indirectly with clinical studies. Agreement was good among all three approaches. The relatively weak binding of analog to thyroxin-binding globulin and prealbumin does not significantly perturb Amerlex FT4 assay results. Binding of the analog by albumin has a small but quantifiable effect on assay results, amounting to an intrinsic bias of 0.08 pmol of free thyroxin per liter per gram of albumin per liter for euthyroid serum samples. This bias is unlikely to be important for most clinical laboratory samples, but it may be significant when one is interpreting results for those rare patients with genetic albumin abnormalities such as analbuminemia or familial dysalbuminemic hyperthyroxinemia. Massively increased concentrations of nonesterified fatty acids (e.g., after treatment with heparin) will lead to a spurious increase in free thyroxin in this and most other techniques, including equilibrium dialysis.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Wilkins TA,Midgley JE,Barron Nsubject
Has Abstractpub_date
1985-10-01 00:00:00pages
1644-53issue
10eissn
0009-9147issn
1530-8561journal_volume
31pub_type
杂志文章abstract：:We measured total and dialyzable calcium concentrations in consecutive sera submitted for routine lithium analysis. Of 98 samples from 61 different individuals, six (6.1%) total calcium results and 32 (33%) dialyzable calcium results were above the respective reference intervals. By comparison, when both total and dia...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-10-01 00:00:00
abstract：:We describe here a nonisotopic immunoassay, based on particle-counting technology, for the determination of urinary albumin. The assay takes only 35 min and has been fully automated on the IMPACT (Acade Diagnostic Systems, Brussels, Belgium) machine. The system measures albumin within a linear range between 6.25 and 5...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-02-01 00:00:00
abstract：:We have separated serum proteins in only 15 min by high-performance liquid chromatography. The identification of several peaks in the chromatographic profile was greatly aided by the use of multiple-wavelength detection. We have found a good correlation between retention times and electrophoretic mobilities. Serum sam...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-09-01 00:00:00
abstract：:In this automated apoenzyme reactivation immunoassay system (Ames Optimate) for thyroxin-binding globulin (TBG), the sample and N6-aminohexylflavin adenine dinucleotide-labeled TBG react sequentially with antiserum. Then apoglucose oxidase is added to combine with the free fraction and generate glucose oxidase activit...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-05-01 00:00:00
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：:We isolated myoglobin from sheep heart by homogenizing cardiac muscle in 70%-saturated ammonium sulfate, followed by chromatography on a column containing carboxymethyl(CM)-Sephadex gel. Two major isoforms of myoglobin, designated Mb 7.9 and Mb 8.1, were separated by chromatofocusing and were distinguished by their di...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
abstract：BACKGROUND:Pompe disease (PD) is the first lysosomal storage disorder to be added to the Recommended Uniform Screening Panel for newborn screening. This condition has a broad phenotypic spectrum, ranging from an infantile form (IOPD), with severe morbidity and mortality in infancy, to a late-onset form (LOPD) with vari...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.259036
更新日期：2017-04-01 00:00:00
abstract：BACKGROUND:Technological advances have resulted in a renaissance of proteomic studies directed at finding markers of disease progression, diagnosis, or responsiveness to therapy. Renal diseases are ideally suited for such research, given that urine is an easily accessible biofluid and its protein content is derived mai...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2011.165969
更新日期：2012-02-01 00:00:00
abstract：:C-reactive protein (CRP) concentrations were serially determined in serum after kidney or heart transplantation. The initial postsurgical CRP response in these patients was compared with that of control patients undergoing related procedures but not subjected to immunosuppressive therapy. Immunosuppression clearly dep...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-04-01 00:00:00
abstract：:Lactate dehydrogenase (LD) isoenzymes 1 and 2 in human serum were separated on a column of diethylaminoethyl-Sephadex. Samples layered on mini-columns were eluted with buffered sodium chloride (100, 150, and 200 mmol/liter). Lactate dehydrogenase activity in column effluents was measured by the Wacker method, and thei...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-03-01 00:00:00
abstract：BACKGROUND:Fecal calprotectin (FC) has been proposed as a marker of inflammatory bowel disease (IBD), but few studies have evaluated its usefulness in patients with chronic diarrhea of various causes. We evaluated the diagnostic accuracy of a FC assay in identifying "organic" causes of chronic diarrhea in consecutive a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.6.861
更新日期：2003-06-01 00:00:00
abstract：:We describe a simple and convenient method for processing small amounts of tissue samples for trace-metal measurements by atomic absorption spectrometry, by use of a modified Parr microwave digestion bomb. Digestion proceeds rapidly (less than or equal to 90 s) in a sealed Teflon-lined vessel that eliminates contamina...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
abstract：:This procedure for routine quantification of albumin in urine is based on the dye-binding properties of albumin with bromphenol blue. The absorbance of 100 microL of urine mixed with 3 mL of color reagent is measured against blank reagent at 610 nm after 30 s. Results vary linearly with albumin concentration up to 6 g...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-02-01 00:00:00
abstract：BACKGROUND:Stability of chemical speciation during sample handling and storage is a prerequisite to obtaining reliable results of trace element speciation analysis. There is no comprehensive information on the stability of common arsenic species, such as inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-11-01 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
abstract：:This article reviews key advances in ion-selective electrode technology that have made potentiometric measurements of ionized calcium (Ca2+) reliable and precise. Our use of two second-generation Ca2+ analyzers (Radiometer ICA1 and NOVA 8) made possible uninterrupted service as volume increased to 31 640 patient tests...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1986-08-01 00:00:00
abstract：:We describe the conjoint measurement in urine of the alcoholic catecholamine metabolites 3,4-dihydroxyphenylglycol (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG). The method involves extraction with ethyl acetate and back-extraction into acetic acid (MHPG), followed by adsorption onto alumina (DHPG). The separation...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-05-01 00:00:00
abstract：BACKGROUND:Heparinized plasma samples allow more rapid analysis than serum samples, but preliminary studies showed lower cardiac troponin T (cTnT) results in plasma. We undertook a multicenter study to characterize this effect for cTnT and cardiac troponin I (cTnI). METHODS:Blood samples were collected with and withou...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,多中心研究
doi：
更新日期：2000-06-01 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：:Currently, we can make the following generalizations about the major long-term complications of diabetes. First, they occur commonly after 10 to 15 years of diabetes. Second, the complications of renal and retinal disease, but not of atherogenic and neurological disease, appear to be related to the severity of hypergl...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,评审
doi：
更新日期：1986-10-01 00:00:00
abstract：:The concentrations of 25 plasma proteins were measured in 22 patients with membranous nephropathy. For some large proteins, the plasma concentrations were increased; there were also large proteins with low plasma concentrations, but small or medium-sized proteins showed uniformly lower plasma concentration than the co...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
abstract：BACKGROUND:Cyclosporin A (CsA) is commonly measured by immunoassay techniques that have a limited analytical range. The consequence of this is that low CsA concentrations that may be clinically significant are difficult to measure and that high concentrations require sample dilution, which introduces error and increase...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：:We describe a simple, rapid fluorometric assay for separate quantitative analysis of procainamide and N-acetylprocainamide in mixtures. The effective lenear range (fluorescence vs. concentration) in serum is 0.1 to 10.0 mg/liter, regardless of the ratio (by weight) of the two drugs from 1:10 to 10:1. Analytical recove...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-12-01 00:00:00
abstract：:Distributions of concentrations of free glycerol in clinical plasma obtained for triglyceride assay were compiled to determine the frequency with which increased concentrations of free glycerol posed a potential problem for clinical interpretation of triglyceride results. Clinical histories were studied in patients wi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
abstract：BACKGROUND:Insulin, growth hormone (GH), and growth factors (insulin-like growth factors [IGFs] and their binding proteins [IGFBPs]) are known to influence fetal growth and also the synthesis/secretion of the recently discovered hormones leptin and ghrelin. METHODS:In 153 delivering mothers and their offspring at birt...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.095299
更新日期：2008-03-01 00:00:00
abstract：:To evaluate their potential usefulness in the differential diagnosis of Cushing's syndrome, we estimated the urinary excretion rates of the following non-metabolized, unbound steroid hormones: pregnenolone, progesterone, 17-OH-pregnenolone, 17-OH-progesterone, dehydroepiandrosterone (DHEA), androstenedione, testostero...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：:Discrepancies among different methods for assaying human growth hormone have been described in various studies. The two major sources of discordant results are the heterogeneity of the antibodies and the different standardization bases used by the assay manufacturers. We propose standardizing assays with 22-kDa biosyn...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-10-01 00:00:00
abstract：BACKGROUND:Fetuin-A inhibits inflammation and has a protective effect against myocardial ischemia. Its deficiency has been found to be associated with cardiovascular death in patients with end-stage renal failure disease. We investigated the association between plasma fetuin-A and clinical outcome after ST-elevation ac...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.084947
更新日期：2007-10-01 00:00:00
abstract：:Detection and characterization of small IgM paraproteins by immunoelectrophoresis are often difficult because of (a) slow diffusion of the macromolecular immunoglobulin, and (b) the obscuring of the light chain, especially kappa, by the light chains of background polyclonal immunoglobulin (the "umbrella effect"). Vari...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
abstract：BACKGROUND:The association between increases in cardiac troponin and adverse cardiac outcomes is well established. There is a growing interest in exploring routine cardiac troponin monitoring as a potential early indicator of adverse heart health trends. Prognostic use of cardiac troponin measurements requires an assay...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2015.242081
更新日期：2015-10-01 00:00:00
