Abstract:
:A modified gas-liquid chromatographic method for determining plasma concentrations of bupivacaine and lidocaine is described, with cyclizine as an internal standard. The extraction procedure requires no solvent evaporation, thus overcoming the problem of drug volatility. Concentrations as low as 0.1 mg/liter can be determined. The plasma sample is made alkaline and extracted into n-hexane, re-extracted into a small volume of an aqueous acid phase, and finally extracted into 50 microliter of methylene chloride after alkalinization. The final extract is assayed by gas chromatography on a 5% OV-17 column. The extraction scheme of the present method eliminates interferences by endogenous plasma constituents.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Zylber-Katz E,Granit L,Levy Msubject
Has Abstractpub_date
1978-09-01 00:00:00pages
1573-5issue
9eissn
0009-9147issn
1530-8561journal_volume
24pub_type
杂志文章abstract::We describe a rapid and simple insulin RIA in which proinsulin and conversion intermediates do not interfere. Three monoclonal antibodies (S1, S2, and S53) were selected for their specificity (directed, respectively, against the B10 region, the junction between A chain and C-peptide, and the junction between B chain a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-07-01 00:00:00
abstract::We present evidence for the utility of an improved assay for the activity of lactate dehydrogenase (EC 1.1.1.27) isoenzymes 1 and 2 in serum, involving inhibition of the H-subunit of LD by pyruvate at pH 7.1. Results correlate well with the LD-1/total LD ratio as evaluated by immunological assay and, as an index to in...
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 sensitive beta-endorphin (beta-EP) radioimmunoassay specific for beta-EP 1-31 applied to human ventricular and lumbar cerebrospinal fluid (CSF). Specificity was documented by reversed-phase HPLC of CSF pools. Simultaneous ventricular and lumbar CSF samples from 13 patients suspected of having normal-pres...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-06-01 00:00:00
abstract:BACKGROUND:Commercial immunoassays for testosterone (Te) may give inaccurate results for samples from women and children, leading to misdiagnosis and inappropriate treatment. We developed a sensitive and specific tandem mass spectrometric assay for measurement of Te at the concentrations encountered in women and childr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.052167
更新日期:2006-01-01 00:00:00
abstract::Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-08-01 00:00:00
abstract::Ornithine carbamoyltransferase (EC 2.1.3.3) activity is a sensitive, specific indicator of hepatocellular injury. This paper describes development of an improved automated procedure for measurement of this activity. Triethanolamine-ethylenediaminetetraacetate is used as a buffer, and activity is determined by measurin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-05-01 00:00:00
abstract::We developed a novel noncompetitive immunoassay format for monoepitopic analytes and describe here a model assay for triiodothyronine (T3), performed on Ciba Corning's ACS:180 analyzer. Acridinium ester (AE)-labeled bivalent anti-T3 was incubated with the sample, producing AE-anti-T3/T3 complexes and unreacted AE-anti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-07-01 00:00:00
abstract::Two-dimensional electroimmunodiffusion is rarely used in clinical chemistry, because its potentialities are not yet widely appreciated. Studying mouse anaphylaxis, we observed with this technique certain striking short- and long-term pathologic changes in several important serum antigens, which aptly demonstrate its u...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-05-01 00:00:00
abstract:BACKGROUND:The American Diabetes Association task force on standardization of insulin assays in 1996 showed wide variation in assay bias. Newer assays are specific for insulin, with several now available on automated immunoassay analyzers. METHODS:In 2004, we compared 11 commercially available insulin assays by analyz...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:10.1373/clinchem.2006.077784
更新日期:2007-05-01 00:00:00
abstract::An electrospray ionization-mass spectrometric procedure has been developed for determining glycohemoglobin. Whole-blood samples from 78 diabetic and 50 nondiabetic subjects (glycation range 3-15%, as determined by electrospray mass spectrometry) were diluted 500-fold in an acidic denaturing solvent and introduced dire...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-05-01 00:00:00
abstract::6-thioguanine (6-TGN) and methyl 6-mercaptopurine nucleotides (Me6-MPNs) are the two major metabolites found in erythrocytes after administration of azathioprine. In an attempt to understand the role of these metabolites in the pharmacologic and toxic activity of thiopurines, we have developed a HPLC method for the si...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-03-01 00:00:00
abstract:BACKGROUND:Cardiac troponin T (cTnT) is the preferred biomarker for the diagnosis of acute myocardial infarction (AMI). It has been suggested that cTnT is present predominantly in fragmented forms in human serum following AMI. In this study, we have used a targeted mass spectrometry assay and epitope mapping using West...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.261511
更新日期:2017-02-01 00:00:00
abstract::We examined the changes in sensitivity and specificity that would occur with alterations in the sample-collection schedule and (or) cutoff criterion for the increase in hydrogen concentration in breath after administration of doses of lactose in the dietary range. In a breath-analysis test to classify individuals as l...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-03-01 00:00:00
abstract::We evaluated the dual-precipitation method for quantitative measurement of lipoproteins as described by Wilson and Spiger [J. Lab. Clin. Med. 82, 473 (1973)] for normo- and hyperlipemic sera, by comparison with the results obtained with ultracentrifugation. If serum with an above-normal triglyceride concentration is a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-07-01 00:00:00
abstract::In response to the pressures of cost reduction, we established and evaluated a carefully integrated program to deliver clinical laboratory services more promptly and efficiently to the intensive care units (ICUs). The new protocol reduced the steps and turnaround time from ordering tests by physicians to reporting res...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-03-01 00:00:00
abstract::The topic of quality control often evokes prolific discussion among those whose business is its administration. Reliable methods for identifying mistakes must be developed in both the manufacture and use of test devices. Unit test devices are uncomplicated to run and provide quick results in a world where speed and si...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1997-05-01 00:00:00
abstract::A new enzymic method is described for the determination of creatine in urine by continuous-flow analysis. The measurement is accomplished by transforming creatine to formaldehyde in reactions catalyzed by creatinase (creatine amidinohydrolase) and sarcosine dehydrogenase. The formaldehyde is reacted with 4-amino-3-hyd...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-11-01 00:00:00
abstract::Gel filtration of serum by use of dextran bisacrylamide beads ("Sephacryl S-200," fractionation range: 5000-250 000 daltons), separates the serum proteins into three distinct peaks. We used an eluent containing (per liter) 140 mmol of sodium, 1.10 mmol of calcium, 0.50 mmol of magnesium, and 10 mmol of 2-([2-hydroxy-1...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-12-01 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::9-(2-Phosphonylmethoxyethyl)adenine (PMEA), (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine (HPMPA), and (R,S)-9-(3-fluoro-2-phosphonylmethoxypropyl)adenine (FPMPA) are selective antiviral agents with activity against a broad spectrum of DNA viruses and retroviruses. A highly sensitive method has been developed to ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-04-01 00:00:00
abstract::The Center for Disease Control (CDC), the New York State Department of Health (NYSDH), the College of American Pathologists, and 23 manufacturers of diagnostic products participated in an interlaboratory study of aspartate aminotransferase (EC 2.6.1.1) methodologies. Six different lyophilized materials were prepared a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-06-01 00:00:00
abstract::To investigate the use of streptavidin-hapten derivatives as potential protein-tracer conjugates for competitive-type immunoassays, we labeled streptavidin with cortisol and compared biotin-binding activity of the conjugates with that of unlabeled streptavidin. In this model system, streptavidin labeled with one to ap...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-01-01 00:00:00
abstract::We describe a simple, highly reproducible kinetic technique for precisely measuring temperature in spectrophotometric systems having reaction cells that are inaccessible to conventional temperature probes. The method is based on the temperature dependence of pseudo-first-order rate constants for the acid-catalyzed hyd...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-05-01 00:00:00
abstract::Serial measurements of the bone and fetal intestinal isoenzymes of alkaline phosphatase (EC 3.1.3.1) in the plasma of 43 term and 43 preterm infants, from birth to six weeks later, indicate that the bone isoenzyme gradually increases over this period in both preterm and term infants fed with unsupplemented commercial ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::Risk can lead to catastrophe. Risk-management systems are highly effective in preventing the catastrophes of fire, earthquakes, and work-site injuries. No such effective systems are present to prevent health and social problems. A practical, cost-effective system to manage risk in children is being developed by the no...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00
abstract::Under the Clinical Laboratory Improvement Act of 1967 the Health Care Financing Administration's proficiency-testing requirement applies to approximately 12,000 hospital, reference, and large-clinic laboratories in the United States. The Wisconsin State Laboratory of Hygiene is approved by the Health Care Financing Ad...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-07-01 00:00:00
abstract:BACKGROUND:The differential diagnosis of D-2-hydroxyglutaric aciduria (D-2-HGA), L-2-hydroxyglutaric aciduria (L-2-HGA), and the combined D/L-2-hydroxyglutaric aciduria (D/L-2-HGA) can be accomplished only by the measurement of the corresponding 2-hydroxyglutarate (2-HG). Available methods for the determination of D- a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.033399
更新日期:2004-08-01 00:00:00
abstract:BACKGROUND:The 2447 A > T pathogenic variation at codon 816 of exon 17 (D816V) in the KIT gene, occurring in systemic mastocytosis (SM), leads to constitutive activation of tyrosine kinase activity and confers resistance to the tyrosine kinase inhibitor imatinib mesylate. Thus detection of this variation in SM patients...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.068205
更新日期:2006-12-01 00:00:00
abstract:BACKGROUND:Whether low plasma 25-hydroxyvitamin D concentrations cause osteoporotic fractures is unclear. We tested the hypothesis that low plasma 25-hydroxyvitamin D concentrations are associated with increased risk of osteoporotic fractures using a Mendelian randomization analysis. METHODS:We genotyped 116 335 rando...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1093/clinchem/hvaa049
更新日期:2020-05-01 00:00:00
abstract::This HPLC/immunoassay procedure measures digoxin in serum with no interference from digoxin metabolites or digoxin-like factors. We used solid-phase (C18 and Diol) extraction, a C18 column with a tetrahydrofuran/water mobile phase, and final quantification by fluorescence polarization immunoassay. Deslanoside and gito...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-12-01 00:00:00