Abstract:
:The potential errors of the one-point calibration technique are described mathematically. I examine the theoretical causes and effects of analytical errors in absorbance and of errors in determining calibration concentration, and discuss techniques for minimizing their impact. The dependence of these errors on the calibration concentration and on the size of the result is considered, and some conclusions are drawn about the choice of calibration concentration.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Kemp GJsubject
Has Abstractpub_date
1984-07-01 00:00:00pages
1163-7issue
7eissn
0009-9147issn
1530-8561journal_volume
30pub_type
杂志文章abstract::A new type of multilayer film analytical element--consisting of a spreading layer, a blocking layer, an enzymic reagent layer, and a transparent layer--has been developed for blood glucose determination. After a spot of whole blood is dropped on the film, the plasma glucose concentration is determined in 6 min without...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-07-01 00:00:00
abstract::We describe a novel radioimmunoassay procedure for the direct estimation of aldosterone in unextracted plasma and serum samples, in which interfering binding proteins are digested by Proteinase K (Tritirachium alkaline proteinase, EC 3.4.21.14), a powerful proteolytic enzyme. Heating at 75 degrees C for 15 min inactiv...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-12-01 00:00:00
abstract::We immunoenzymometrically measured creatine kinase (CK) isoenzyme MB in extracts of myocardium and in homogenates of five different skeletal muscles. CK-MB concentrations in the former averaged 80.9 micrograms/g wet tissue; in the skeletal muscles it varied widely, being (e.g.) 25-fold greater in diaphragm than in pso...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
abstract::We tested 231 urine samples by six immunoassay methods--EMIT d.a.u., EMIT II, Roche Abuscreen Online, Abbott TDx, Diagnostic Products Corp. (DPC) double-antibody radioimmunoassay (RIA), and Biosite Triage--and by negative chemical ionization gas chromatography/mass spectrometry to determine how the immunoassays perfor...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-03-01 00:00:00
abstract::Antithrombin III (AT III) activity was determined with two different new chromogenic substances--Chromozym-TH (Tos-Gly-Arg-p-nitroanilide; Boehringer Mannheim) and alpha-N-carbobenzyl-oxy-L-lysine-thiobenzyl ester (Du Pont)--with both a discrete (aca) and a centrifugal analyzer (COBAS BIO). The correlation between the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-11-01 00:00:00
abstract::To secure a successful product in today's era of cost containment, manufacturers and developers of new in vitro diagnostic technologies must consider payment issues--coverage and reimbursement by healthcare insurers--as critical market forces that must be addressed in the business plan. Similar to the regulatory hurdl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-09-01 00:00:00
abstract::We describe the process of certification for a gamma-glutamyltransferase reference material (CRM no. 319). Fifteen laboratories participated to this interlaboratory evaluation. All steps of the measurements were controlled in an effort to locate potential sources of variations. In particular, the exclusion of some dat...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-11-01 00:00:00
abstract:BACKGROUND:The counting of leukocytes and erythrocytes in cerebrospinal fluid (CSF) is still performed microscopically, e.g., using a chamber in most laboratories. This requires sufficient practical experience, is time-consuming, and may constitute a problem in emergency diagnostics. Specific automated systems for CSF ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-02-01 00:00:00
abstract::We assessed the LKB "Delfia" (time-resolved dissociation-enhanced lanthanide fluoroimmunoassay) and the Amersham "Amerlite" (enhanced luminescent immunometry) assays of thyrotropin in serum. Both assays are sensitive (respective detection limits: 0.02 and 0.04 milli-int. unit/L) and have very good within- and between-...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-08-01 00:00:00
abstract:BACKGROUND:Although microRNAs (miRNAs) play essential roles in spermatogenesis, little is known about seminal plasma miRNAs in infertile men. We investigated the profile of seminal plasma miRNAs in infertile men to identify miRNAs that are altered in infertility; we then evaluated their diagnostic value. METHODS:Semin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.169714
更新日期:2011-12-01 00:00:00
abstract::Laboratories of the Lipid Research Clinics Program (LRC) maintained the accuracy of their measurements of total cholesterol by using seven pooled serum calibrators supplied by the Centers for Disease Control (CDC). Over the 11-year life of the LRC, each calibrator was prepared in succession and a target value was assi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-04-01 00:00:00
abstract::We modified the liquid-chromatographic assay of Schleicher and Wieland (J Clin Chem Clin Biochem 1981; 19:81-7) for measuring lysine-bound glucose in serum proteins, increasing its performance and practicality. After precipitating serum proteins from 10- to 50-microL samples with ethanol (700 mL/L) and hydrolyzing the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-09-01 00:00:00
abstract::Intra- and interindividual components of biological variation have been determined for total thyroxin (TT4), free thyroxin (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyrotropin (TSH). Calculated analytical goals (CV, %) for the precision required for optimal patient care are: TT4 less than ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-06-01 00:00:00
abstract::Even in the absence of detectable ethanol or visible lipemia, a large plasma osmolal gap is the usual finding in cases of diabetic ketoacidosis. This gap decreases to an insignificant value within 20 h of treatment. Detailed biochemical analysis of six cases showed that, on average, the gap could be almost wholly acco...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-05-01 00:00:00
abstract::We describe a fixed-time, enzymatic, reaction-rate procedure for determining plasma ammonia with a centrifugal analyzer (Rotochem IIA/36; American Instrument Co., silver Spring, MD 20910), with NADPH as cofactor. The reaction is based on that of da Fonseca-Wollheim's modification [J. Clin. Chem. Clin. Biochem. 11, 421...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-04-01 00:00:00
abstract::We tested the diagnostic sensitivity of various urinary analytes for detecting cadmium-induced nephropathy at an early stage. We investigated 73 healthy persons (control group 1) and individuals exposed to cadmium, either environmentally (n = 36, risk group 2) or occupationally (n = 62, exposed group 3). All data were...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-05-01 00:00:00
abstract::We investigated two techniques of immunoblotting--the Western blot and the dot blot--for use in detecting prostatic acid phosphatase (PAP, EC 3.1.3.2). We used polyclonal antisera to human PAP, produced in rabbits by hyperimmunization with purified PAP, and PAP-specific monoclonal antibodies in the immunoenzymatic pro...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-10-01 00:00:00
abstract:BACKGROUND:The discovery of cell-free fetal DNA in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis and monitoring. Among the fetal markers that have been described, methylation markers are sex and polymorphism independent. Methylation-sensitive restriction endonucleases are commonly u...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.092619
更新日期:2007-11-01 00:00:00
abstract:BACKGROUND:5α-Reductase 2 deficiency (5ARD) is a known cause of 46,XY disorders of sex development (DSD). Traditionally, the diagnosis relies on dihydrotestosterone (DHT) measurement, but the results are often equivocal, potentially leading to misdiagnosis. We reviewed alternative approaches for diagnosis of 5ARD. MET...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2012.196501
更新日期:2013-05-01 00:00:00
abstract::We compared three current methods (immunoinhibition, "Isomune-CK" immunoprecipitation, and the Tandem-E CKMB II immunoenzymometric assay) for determination of creatine kinase (CK; EC 2.7.3.2) isoenzyme MB in serum. Although results inter-correlated well, the immunoinhibition assay gave higher activity values. Atypical...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-01-01 00:00:00
abstract::We compared the activities of thyroid-stimulating antibodies (TSAb) measured in cultures of human thyrocytes and the values for thyrotropin-receptor antibodies (TRAb) as measured with a commercial kit based on use of radiolabeled receptors. Sera were obtained from patients with Graves' disease before, during, and afte...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-07-01 00:00:00
abstract:BACKGROUND:Although minimum regulatory standards exist for determining QC testing frequency, decisions regarding when and how to run QC samples are not standardized. Most QC testing strategies test control samples at fixed time intervals, often placing the samples in the same position on an instrument during subsequent...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.083311
更新日期:2007-04-01 00:00:00
abstract::Published estimates of the imprecision characteristics of immunoassays are often based on quantities of data that seem to be inadequate. The increasing use of imprecision profiles has not necessarily improved the situation. We describe and illustrate a method of computing 95% confidence intervals for profiles estimate...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-07-01 00:00:00
abstract::In considering factors that might influence measurement of free thyroxin (T4), we evaluated the proportion (%) of T4 that could be stripped from thyroxin-binding globulin (TBG). The percentage of free T4 was measured in serially diluted sera from four normal subjects, four patients with hyperthyroidism or hypothyroidi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
abstract::With the ultramicroanalytical system described here we can measure glucose in 1 microL of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops. The reflectance of these spots is measured with a reflectance digital matrix photome...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-12-01 00:00:00
abstract::Concentrations of free thyroxin (T4) and free triiodothyronine (T3) were measured in sera from pregnant women, in subjects with congenitally increased or decreased thyroxin-binding globulin (TBG), and in euthyroid controls. Measured free hormone concentrations were compared with calculated values for free hormone deri...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-08-01 00:00:00
abstract::We describe an enzyme-linked two-site immunoassay for quantitation of intact insulin in human serum and plasma. The method uses two murine monoclonal antibodies that bind to two different epitopes on the insulin molecule. The immunoassay is specific. Human proinsulin is not bound by the antibodies, and the binding of ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-04-01 00:00:00
abstract::We studied the relationship between serum erythropoietin (EPO) concentration and iron status in 67 patients undergoing chronic hemodialysis. Serum concentrations of EPO were measured by RIA with recombinant human EPO. The geometric mean of the serum EPO concentration was 10.9 int. units/L (mean +/- SD range = 7.8 - 15...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-02-01 00:00:00
abstract::We describe a sensitive method for the determination of vanadium in biological substances by atomic absorption spectroscopy. By using background correction and pyrolytically coated graphite tubes with flameless apparatus, this vanadium assay has a sensitivity of 65 pg and a detection limit of 30 pg, approximately sixf...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-01-01 00:00:00
abstract::The use of 4-chlorotestosterone acetate by farmers for cattle fattening was recently demonstrated although the use of this anabolic steroid is strictly forbidden in the European Union. We investigated the metabolism of 4-chlorotestosterone acetate in the bovine species after intramuscular and oral administration. Nine...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-05-01 00:00:00