Abstract:
:I developed a standard procedure for assessing sensitivity, intra-assay precision, parallelism of sample dilutions, and assay drift, using a single trial assay kit. I used this to compare the performance of 10 commercial kits with an in-house radioimmunoassay for human thyrotropin. No one kit stood out as clearly superior overall. Differences in calibration between kits were evident in a comparison of thyrotropin concentrations measured in clinical samples, and by direct comparison of standards from different kits in a single assay. However, all kits gave clinically consistent results with respect to their published normal reference interval. Moreover, the performance of human thyrotropin assay kits has improved during the 14 months of this study.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Evans MCsubject
Has Abstractpub_date
1988-01-01 00:00:00pages
123-7issue
1eissn
0009-9147issn
1530-8561journal_volume
34pub_type
杂志文章abstract::The S-peptide and S-protein fragments of ribonuclease S (RNase S, no EC no. assigned) have been immobilized onto separate Sepharose gels via a "leash" of polycytidylic acid substrate. Each of these gels releases its RNase fragment when treated with the complementary enzyme fragment or with RNase A (EC 3.1.27.5), and t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::We assessed the performance of three commercially available polyclonal immunoassays for apparent cyclosporine in 120 whole-blood specimens collected from transplant recipients just before their next dose of cyclosporine (CsA). The assays were (a) Abbott's TDx fluorescent polarization immunoassay for CsA and its metabo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::I describe a gas-chromatographic procedure involving a nitrogen detector for "free" (or "unbound") phenytoin in the concentration range 0.2-4.0 mg/L in ultrafiltrates of plasma. The CV (n = 10) for the assay was 2.9% for a 0.49 mg/L concentration, 1.5% for 2.02 mg/L. The sensitivity was 0.05 mg/L. The ultrafiltration ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-03-01 00:00:00
abstract::Creatine kinase isoenzyme BB (CK-BB) is found in the serum of patients with various types of cancer. Using both radioimmunoassay and agarose electrophoresis, we found abnormal amounts of this isoenzyme in the serum of 15 of 17 patients with untreated prostatic carcinoma. Among patients with other types of adenocarcino...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-08-01 00:00:00
abstract:BACKGROUND:The majority of patients with chronic kidney disease are diagnosed and monitored in primary care. Glomerular filtration rate (GFR) is a key marker of renal function, but direct measurement is invasive; in routine practice, equations are used for estimated GFR (eGFR) from serum creatinine. We systematically a...
journal_title:Clinical chemistry
pub_type: 杂志文章,meta分析
doi:10.1373/clinchem.2017.276683
更新日期:2018-03-01 00:00:00
abstract:BACKGROUND:Concerns exist regarding how the 99th percentile upper reference limit (URL) of cardiac troponin (cTn) is determined and whether it should be derived from normal healthy individuals. CONTENT:The 99th percentile URL of cTn is an important criterion to standardize the diagnosis of myocardial infarction (MI) f...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa158
更新日期:2020-09-01 00:00:00
abstract::In the present clinical evaluation of Triage immunoassay for detection of drugs of abuse, we examined a possible connection between the laboratory skills of the personnel using it and the quality of analytical results; we also evaluated the degree of concordance between the Triage results and those obtained by an inst...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-09-01 00:00:00
abstract::Ion chromatography is a new analytical technique in which the ions to be analyzed are separated on a special pellicular ion-exchange column. Once separated, the effluent from the separating column passes into a second ion-exchange column, which removes the eluent or buffer ions from the moving phase without removing t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-09-01 00:00:00
abstract::Direct-injection analysis for phenylalanine in plasma by isocratic "high-performance" liquid chromatography (HPLC) is described. For chromatographic separation I use an internal-surface reversed-phase silica support. The method involves ultraviolet detection, requires as little as 10 microL of plasma (routinely 20 mic...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-06-01 00:00:00
abstract:BACKGROUND:Non-(1-84) parathyroid hormone (PTH) fragments are large C-terminal fragments of PTH with a partially preserved N-terminal structure. They differ from other C-terminal PTH fragments, which do not have an N-terminal structure and do not react in intact PTH assays. We aimed to identify the minimal N-terminal s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.040485
更新日期:2005-01-01 00:00:00
abstract:BACKGROUND:The sex differential in coronary heart disease (CHD) risk, which is not explained by male/female differences in lipid and lipoprotein concentrations, narrows with age. We examined whether this differential CHD risk might, in part, be attributable to the sizes of lipoprotein particles or concentrations of lip...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.032763
更新日期:2004-07-01 00:00:00
abstract:BACKGROUND:Plasma concentrations of the peptides midregional proadrenomedullin (MR-proADM), midregional proatrial natriuretic peptide (MR-proANP), and C-terminal endothelin-1 precursor fragment (CT-proET-1) are increased in various cardiovascular conditions. However, there is limited information about the association a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.193656
更新日期:2013-04-01 00:00:00
abstract::The most popular pretreatment method of plasma samples for the measurement of ascorbate (AsA) and dehydroascorbate (DHA) has been an acidic deproteinization via metaphosphoric acid or trichloroacetic acid. In general, DHA is absent in plasma samples prepared from human blood in a conventional manner. However, when the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-04-01 00:00:00
abstract::The effect of serum-clot contact time on laboratory results was studied by dividing each blood specimen into four blood collection tubes. The control sera were separated from the clot within 30 min of the collection. The other tubes were incubated at 32 degrees C, and the sera were separated at 3, 6, and 24 h. The ser...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-06-01 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::In photometry, where both the product formed and one or several reactants absorb light at the same wavelength, the absorbance of the "blank" of the sample at the end of the reaction may be less than that measured at the beginning of the reaction, because of consumption of reactant(s). The blank correction factor for t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract:BACKGROUND:We analyzed the low-dose (1 microg) rapid adrenocorticotropic hormone test (LDST) in 17 patients with a normal hypothalamic-pituitary-adrenal axis to determine reference intervals for the LDST on the basis of poststimulation cortisol increments. METHODS:We analyzed test results for 17 patients (14 females a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.061267
更新日期:2006-04-01 00:00:00
abstract::Four routine assays commonly used for monitoring plasma methotrexate (MTX) during high-dose therapy were validated by HPLC as the comparison method. MTX and its main metabolite, 7-hydroxymethotrexate (7-OHMTX), were analyzed by HPLC with postcolumn derivatization and fluorometric detection. About 200 clinical plasma s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-01-01 00:00:00
abstract:BACKGROUND:KLK5 is a newly discovered human kallikrein gene. Many kallikrein genes have been found to be differentially expressed in various malignancies, and prostate-specific antigen (PSA; encoded by the KLK3 gene) is the best tumor marker for prostate cancer. Like the genes that encode PSA and other kallikreins, the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-08-01 00:00:00
abstract::We evaluated the homogeneous enzyme immunoassay ("EMIT") of serum thyroxine with use of an ABA- 100 Bichromatic Analyzer, modified with an auxiliary dispenser syringe and a dual probe assembly. The modification allows two reagents to be dispensed at one time. The sera must be pre-treated with 0.1 mol/liter NaOH. The p...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-01-01 00:00:00
abstract::We compared five ion-selective electrodes (ISEs; AVL 985S, Baxter Lytening 2Z, Beckman EL-ISE, Ciba-Corning 654 Na/K/Li, and Nova CRT 11) and a colorimetric method (Ektachem) for determination of lithium with flame atomic absorption and atomic emission spectroscopy. We evaluated precision, recovery, interference by dr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-06-01 00:00:00
abstract::We describe a new liquid-chromatographic method with fluorescence detection for direct simultaneous determination of four urinary sulfate conjugates of 17-oxosteroids (17OS), without use of solvolysis or enzymatic hydrolysis. The 17OS sulfates in urine samples are extracted with benzene as ion pairs in the presence of...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-05-01 00:00:00
abstract::We describe a group of glycoproteins that are synthesized and released by human breast tumors maintained in organ culture and similar glycoproteins released by a human breast carcinoma cell line (BT-20). The electrophoretic mobility of these glycoproteins on cellulose acetate is consistent with increased glycoprotein-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-11-01 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 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:BACKGROUND:Small RNAs are key players in the regulation of gene expression and differentiation. However, many different classes of small RNAs (sRNAs) have been described with distinct biogenesis pathways and, as a result, with different biochemical properties. To analyze sRNAs by deep sequencing, complementary DNA synt...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2019.305045
更新日期:2019-12-01 00:00:00
abstract::Values of low-density lipoprotein (LDL) cholesterol (C) according to the Friedewald formula (Clin Chem 1972;18:499-502) were compared with those obtained by lipoprotein fractionation in 98 healthy subjects (control group), 135 specimens from patients with peripheral vascular and cerebrovascular disease (atheroscleroti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-08-01 00:00:00
abstract::Two families with benign hyperphosphatasemia of intestinal origin were studied and compared with six other cases reported in the literature. No evidence of clinical abnormalities or explanations for the unusual enzyme concentrations were found. Agarose gel electrophoresis of alkaline phosphatase (ALP, EC 3.1.3.1) isoe...
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 sensitive radioimmunoassay for rapidly determining the concentration of thyroxine in 10 microL of human serum. Aggregated antithyroxine antibodies are used to separate bound and free hormone. This speeds the assay and economizes on reagents without loss of sensitivity, specificity, or precision. Results ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-03-01 00:00:00
abstract::Of 98 patients' specimens examined for alkaline phosphatase (EC 3.1.3.1) isoenzymes by electrophoresis on cellulose acetate membrane after incubation with neuraminidase, 50 showed only a single liver or bone isoenzyme staining band; in 15 of these, the tissue origin of the fraction could not be accurately identified f...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-07-01 00:00:00