Abstract：
BACKGROUND:To address the continuing need for the standardization of clinical human cardiac troponin I (cTnI) assays, NIST, with the assistance of the AACC/IFCC Cardiac Troponin I Standardization Committee, has developed a new certified reference material, Standard Reference Material (SRM) 2921: Human Cardiac Troponin Complex. METHODS:The concentration of cTnI in SRM 2921 was determined through a combination of reversed-phase liquid chromatography (LC) with ultraviolet detection and amino acid analysis. Characterization of the intact troponin subunits was accomplished through reversed-phase LC coupled with mass spectrometry. Posttranslational modifications to the cTnI in SRM 2921 were investigated by combining proteolytic digestion with matrix-assisted laser desorption/ionization mass spectrometry. Additionally, reference concentration values for cTnT and cTnC were also determined. RESULTS:The concentration of human cTnI in SRM 2921 is 31.2 (1.4) mg/L (where 1.4 mg/L is the uncertainty at a 95% level of confidence), as certified through a method that provides traceability to the International System of Units (SI). Reference concentration values of the cTnT and cTnC subunits were determined to be 36.9 (3.8) mg/L and 24.2 (1.3) mg/L, respectively. CONCLUSIONS:This first cTnI reference material should provide SI traceability to clinical cTnI assays once commutability has been validated, and could assist in the international harmonization of cTnI assays as a tool for understanding the underlying causes of interassay variability.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Bunk DM,Welch MJdoi
10.1373/clinchem.2005.051359subject
Has Abstractpub_date
2006-02-01 00:00:00pages
212-9issue
2eissn
0009-9147issn
1530-8561pii
clinchem.2005.051359journal_volume
52pub_type
杂志文章abstract：BACKGROUND:The single cell represents the basic unit of all organisms. Most investigations have been performed on large cell populations, but understanding cell dynamics and heterogeneity requires single-cell analysis. Current methods for single-cell analysis generally can detect only one class of analytes. METHODS:Re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2012.191445
更新日期：2012-12-01 00:00:00
abstract：:We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitiv...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-09-01 00:00:00
abstract：:We measured advanced glycosylation end products in the mesenteric artery of 37 patients (ages 29-82 years), 34 of whom were nondiabetic. Samples of arterial tissue were obtained during bowel resectioning. Advanced glycosylation end products were measured as collagen-linked fluorescence (excitation wavelength 370 nm, e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-04-01 00:00:00
abstract：:I describe a micro-scale method for determining lead in whole blood by utilizing a graphite furnace. Sample pretreatment consists of fivefold dilution with a dilute surfactant. The method is directly calibrated with lead standards prepared in dilute HNO3. To eliminate a small, nonspecific absorption signal from the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-04-01 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：:We have developed a liquid chromatography-isotope dilution mass spectrometry procedure to quantify total cholesterol in serum. A particle-beam interface was used for coupling the liquid chromatograph and the mass spectrometer. After electron impact ionization the ions m/z = 386 and m/z = 389 were used for selective io...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-10-01 00:00:00
abstract：:We report the first solid-phase radioimmunoassay for triiodothyronine with use of antibody-coated tubes, which is designed specifically for the fully automated radioimmunoassay instrument, Micromedic Systems' "Concept 4 Automatic Radioassay." Antisera to triiodothyropropionic acid/bovine serum albumin were raised in r...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-05-01 00:00:00
abstract：PURPOSE:To review information on the use of laboratory tests in screening, diagnosis, and monitoring of acute and chronic hepatic injury. DATA SOURCES AND STUDY SELECTION:A MEDLINE search was performed for key words related to hepatic diseases, including acute hepatitis, chronic hepatitis, alcoholic hepatitis, cirrhos...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：2000-12-01 00:00:00
abstract：:Using automated measurements of kappa and lambda light chains and IgG, IgA, and IgM, we assessed the utility of the kappa/lambda ratio and the heavy chain/light chain ratio in characterizing monoclonal immunoglobulins previously identified by sensitive electrophoresis on agarose gel and typed by immunofixation or immu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:We describe an improved procedure for the preparation of plasma or serum for determination of theophylline by reverse phase high-performance liquid chromatography. Quantitative results are available in less than 30 min from receipt of sample. The chromatogram is complete in 8 to 16 min, which includes the use of an in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:We have developed and evaluated a new procedure for detecting trends in quality-control measurements and applied it to laboratory data. The method requires the use of sequential or "moving" slope estimates to identify trends. Formulae are derived to estimate the regression error for the moving slope directly from the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-03-01 00:00:00
abstract：:We describe a method for determination of guanidino compounds in plasma and erythrocytes. The compounds are separated by liquid chromatography, the concentrations in the effluent being estimated fluorometrically (Trans. Am. Soc. Artif. Intern. Organs 24: 61, 1978). Guanidinoacetic acid, guanidinosuccinic acid, guanidi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-11-01 00:00:00
abstract：:We present a unified approach to the use of linear models and matrix least squares with the intention of providing a better understanding of the techniques themselves and of the statistics that arise from these techniques as they are used in clinical chemistry. Emphasis is placed on the importance of appropriate exper...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-06-01 00:00:00
abstract：:Erythrocyte protoporphyrin content is increased in several human and veterinary disorders in which heme synthesis is disrupted. The nature of the defect determines whether zinc protoporphyrin, unchelated (free) protoporphyrin, or both are present in the erythrocytes. Extraction of the protoporphyrin into acetone/water...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-02-01 00:00:00
abstract：BACKGROUND:Lysosomal storage disorders (LSDs) comprise more than 40 genetic diseases that result in the accumulation of products that would normally be degraded by lysosomal enzymes. A tandem mass spectrometry (MS/MS)-based method is available for newborn screening for 5 LSDs, and many laboratories are initiating pilot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.111864
更新日期：2009-01-01 00:00:00
abstract：:A rapid technique (5-10 min) has been developed for fractionating nucleotides from base and nucleoside contaminants in acid extracts of cells, by adsorption to silica gels. Silica gels (1-mL bed volume) were washed with 5 mL of water then with 5 mL of acetonitrile/water (90/10 by vol). After applying 3-mL samples, adj...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-09-01 00:00:00
abstract：BACKGROUND:The resurgence of the parasitic disease schistosomiasis calls for more efficient diagnostic tests. We developed a rapid, simple, portable, and sensitive immunoagglutination assay that uses SiO(2) particles and quartz crystal microbalance (QCM) for quantifying Schistosoma japonicum (Sj) antibodies (SjAb). ME...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.071555
更新日期：2006-11-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-12-01 00:00:00
abstract：:Proteinuria, long recognized as a sign of renal disease, is a common laboratory abnormality in children and adults. Proteinuria may be transient or persistent; when persistent, the cause must be determined. Proteinuria may be primarily glomerular or tubular in origin. Glomerular proteinuria is usually an important con...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1989-05-01 00:00:00
abstract：:We describe a procedure for determining thiocyanate in plasma with a Technicon AutoAnalyzer I, modified with a 50-mm tubular flow cell to increase the sensitivity of thiocyanate detection. The procedure is suitable for distinguishing cigarette smokers from non-smokers, the mean for smokers being 151 (SD 43) micromol/L...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-03-01 00:00:00
abstract：:Human myocardial creatine kinase isoenzyme MM is present as a single form in tissue, but upon its release into plasma two additional forms, with faster anodal migration, are apparent on polyacrylamide electrophoresis. We designate the three forms as MM3, MM2, and MM1 in increasing order of anodal mobility. When tissue...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
abstract：BACKGROUND:Cardiac troponins are specific biochemical markers of myocardial injury used in the diagnosis of acute myocardial disease and cardiac risk stratification. To avoid misclassification of patients, troponin assays must demonstrate precision at the low end of the measuring range. We report our evaluation of the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.057216
更新日期：2006-02-01 00:00:00
abstract：:A new computer-interfaced system of general applicability in the clinical laboratory has been built. The system is constructed around a new type multicuvette. Quantitation is currently by spectrophotometry and is on-line, with use of a mini-computer with output going to an electrostatic printer/plotter. The system can...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-08-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1987-02-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1985-09-01 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
abstract：BACKGROUND:The B-type natriuretic peptides (BNP and N-terminal pro-BNP) are secreted by the heart and, in the case of BNP, serve to maintain circulatory homeostasis through renal and vascular actions and oppose many effects of the renin-angiotensin system. Recent evidence suggests that in patients with severe heart fai...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.210435
更新日期：2014-03-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.256768
更新日期：2016-07-01 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：BACKGROUND:B-type natriuretic peptide (BNP), which is activated in heart failure (HF), is processed to an active form by corin. The corin gene is expressed in the human heart and kidney, but corin protein expression in the heart, kidney, and circulation, along with whether proBNP is processed by circulating corin, rema...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.153908
更新日期：2011-01-01 00:00:00
