Abstract:
:The Cardiovascular Health Study is an observational cohort study of risk factors for cardiovascular disease in 5201 participants, ages > or = 65 years. We report the methods and quality-assurance results for blood procurement, processing, shipping, storage, and sample analysis used during the first examination period (May 1989-June 1990). The most frequent difficulty in phlebotomy and processing was the requirement of more than one venipuncture (in 2.6% of the participants). The CVs for control materials ranged from 0.93% for glucose to 10.7% for insulin; most were < 4%. In addition to standard quality-assurance methods, we applied two other methods: technical error calculation for replicates, and weighted linear regression to assess time trend in results of control materials. After outliers were excluded, technical error values ranged from 1.7 for uric acid to 18.8 for insulin. Factor VII and factor VIII had slight trends over the 12-month analysis period. Results of quality-assurance analyses used to resolve problems were successful, thereby improving the second laboratory examination.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Cushman M,Cornell ES,Howard PR,Bovill EG,Tracy RPsubject
Has Abstractpub_date
1995-02-01 00:00:00pages
264-70issue
2eissn
0009-9147issn
1530-8561journal_volume
41pub_type
杂志文章abstract:BACKGROUND:Little is known about trace metal alterations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentrations of trace elements. Because these patients are at risk for alterations of trace elements as well as for ...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:
更新日期:1999-09-01 00:00:00
abstract:BACKGROUND:The bleeding time (BT) test predicts a higher bleeding complication rate in populations at risk for inherited or acquired platelet dysfunction, but it is of limited assistance in evaluating individual patients. There are no reports of clinical outcomes after discontinuation of the BT test. METHODS:Interview...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2001-01-01 00:00:00
abstract:BACKGROUND:Different technologies, such as quantitative real-time PCR or microarrays, have been developed to measure microRNA (miRNA) expression levels. Quantification of miRNA transcripts implicates data normalization using endogenous and exogenous reference genes for data correction. However, there is no consensus ab...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2015.239459
更新日期:2015-11-01 00:00:00
abstract::A dissociation-enhanced lanthanide fluoroimmunoassay of serum cortisol based on time-resolved fluorescence is described. The assay is a direct assay, where cortisol immobilized on the wall of a microtiter-strip well competes with cortisol in the sample for the europium-labeled polyclonal antibody. The amount of bound ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-10-01 00:00:00
abstract::We measured morphine and codeine in commercially available poppy seeds and in serum and urine samples from healthy adults who had ingested these poppy seeds. Four brands of black poppy seeds, examined by gas chromatography-mass spectroscopy (GC-MS) with deuterated internal standards, contained from 17 to 294 microgram...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-06-01 00:00:00
abstract::We report here the development of a new method that allows continuous determination of the oxygen dissociation curve for microsamples (600 mul) of whole blood under conditions of pH, pCO2, methemoglobin concentration, and 2,3-diphosphoglycerate content closely approaching those found in the circulatory system. The met...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-11-01 00:00:00
abstract::We have compared the operational, medical, and fiscal consequences of performing urgent glucose testing at the bedside vs in the central laboratory. The turnaround time (TAT) with bedside testing was only 1-2 min shorter than that from the central laboratory, to which specimens are sent by pneumatic tube and from whic...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-08-01 00:00:00
abstract::We evaluated a new commercially available partially purified reduced bovine hemoglobin solution (RBHS) and a new tonometer for use in the quality control of blood gas analyzers. RBHS is manufactured in three different formulations, each corresponding to three different bicarbonate-buffering capacities and concentratio...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-05-01 00:00:00
abstract::The measurement of glycohemoglobin (GHb) by boronate affinity chromatography is useful in monitoring long-term glucose control in diabetic subjects. The inherent disadvantage of this method is the hands-on time required because the hemoglobin fractions are separated on individual disposable columns. To overcome this d...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-01-01 00:00:00
abstract::The identification of nicotinamide-N1-oxide as a metabolite in the urine of a schizophrenic patient prompted a study of the relative metabolism of nicotinic acid and nicotinamide in mental patients and healthy volunteers. Metabolites quantified included N1-methyl-2-pyridone-5-carboxamide, N1-methyl-4-pyridone-3-carbox...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-11-01 00:00:00
abstract::Adrenocortical causes of hypertension are established by examining the mineralocorticoid hormones produced in the zona glomerulosa and zona fasciculata. In the zona glomerulosa, aldosterone excess leads to hypertension, hypokalemia, and suppressed plasma renin activity, with increased concentrations of urinary aldoste...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1991-10-01 00:00:00
abstract:BACKGROUND:There is need for a reference method for transferrin glycoforms in serum to which routine immunologic methods for the alcohol marker carbohydrate-deficient transferrin (CDT) can be traceable. We describe an improved HPLC method for transferrin glycoforms. METHODS:Transferrin was iron-saturated by mixing the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.023341
更新日期:2003-11-01 00:00:00
abstract::The human ras gene plays a fundamental role in the transduction of extracellular signals to the nucleus, thereby regulating cell growth and differentiation. Point mutations in the ras gene convert it into a transforming oncogene that has been found in many solid and hematologic malignancies. We describe a rapid and se...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-05-01 00:00:00
abstract::Methods are described for detection of lactate dehydrogenase (LDH) inhibitors in preparations of reduced nicotinamide adenine dinucleotide. They are (a) comparison of values by kinetic methods with those measured for highly purified NADH and (b) examination of Lineweaver-Burk plots. Chromatographic inhomogeneities are...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-10-01 00:00:00
abstract:BACKGROUND:Gradient gel electrophoresis (GGE) and nuclear magnetic resonance (NMR) spectroscopy are both widely accepted methods for measuring LDL and HDL particle size. However, whether or not GGE- or NMR-measured LDL or HDL particle size predicts coronary heart disease (CHD) risk to a similar extent is currently unkn...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.140939
更新日期:2010-05-01 00:00:00
abstract::This new assay procedure for diaphorase eliminates problems of high blank rates and nonlinear kinetics associated with other methods. The dye thiazolyl blue tetrazolium bromide is reduced in the presence of NADH and diaphorase to yield a colored formazan, which as maximum absorbance at 560 nm. ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-12-01 00:00:00
abstract::Quantification of ethanol by a radiative energy attenuation (REA) technique was evaluated and compared with results by gas-liquid chromatography (GLC) and by the Du Pont aca. Within-assay CVs were less than 5.5%. Between-assay CVs ranged from 1.9% to 6.0% for serum and blood controls at concentrations of 0.5, 1.0, and...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 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::The immunoreactivity of anti-triiodothyronine (anti-T3) IgG, pretreated at acidic pH and adsorbed onto polystyrene beads, was significantly greater than that determined for native anti-T3 IgG immobilized at optimum pH 3.5. Acidic-pH-pretreated IgG, adsorbed at pH 7.0 onto ethanol-treated beads, had less immunoreactivi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-03-01 00:00:00
abstract::Recombinant DNA techniques are contributing to the understanding of the pathogeneses of genetic, neoplastic, and viral diseases, and are used in the diagnosis of certain genetic and viral diseases. Such techniques will have wider application in the future and will play an increasing role in the clinical laboratory. Th...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-06-01 00:00:00
abstract:BACKGROUND:Monitoring of the concentration of gentamicin in serum and plasma during therapy is widely recommended and practiced in hospitals. Our aim was to develop a homogeneous immunoassay based on particle-enhanced turbidimetric inhibition immunoassay technology to quantify gentamicin on the Dimension clinical chemi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-03-01 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:BACKGROUND:Advances in the biological sciences and technology are providing molecular targets for diagnosing and treating cancer. Current classifications in surgical pathology for staging malignancies are based primarily on anatomic features (e.g., tumor-node-metastasis) and histopathology (e.g., grade). Microarrays to...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:2002-08-01 00:00:00
abstract::Erythromycin, phenazopyridine, methenamine mandelate, acetazolamide, and ascorbic acid reportedly interfere with the Porter-Silber reaction in the determination of urinary 17-hydroxycorticosteroids. Sodium bisulfite, added to the urine after hydrolysis with glucuronidase, removed almost all nonsteroidal interferences ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-11-01 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:BACKGROUND:Nandrolone is one of the most abused anabolic steroids, and its use in doping is increasing, as revealed by numerous positive cases during recent years in various sports. Different authors have reported the possible natural production of nandrolone metabolites in humans, and some of these authors argued that...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:10.1373/clinchem.2003.022848
更新日期:2004-02-01 00:00:00
abstract::A continuous-monitoring method for measuring acid phosphatase activity with alpha-naphthyl phosphate as the substrate was critically evaluated and modified. Using partially purified prostatic acid phosphatase, we show that certain conditions for the assay must be satisfied to ensure linearity. These conditions include...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-12-01 00:00:00
abstract::A direct mehtod [Clin. Chim. Acta 46, 113 (1973)] for determination of inorganic phosphate in serum was adapted for use with a centrifugal analyzer. Contamination is minimized and analysis rate maximized by doing the reaction in the reagent wells of the transfer disc and by utilizing the high-speed spectrophotometric ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-02-01 00:00:00
abstract::We review the following labels used as substitutes for radioisotopes in immunoassay systems: bacteriophages, chemiluminescence precursors, fluorochromes, fluorogens, fluorescence quenchers, enzymes, coenzymes, inhibitors, substrates, various particulates, metal atoms, and stable free radicals. New methods for performi...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1981-07-01 00:00:00