Abstract：
:We describe a mass-fragmentographic method for determination in urine of the following metabolites of L-3,4-dihydroxyphenylalanine and dopamine: vanillactic acid, 3,4-dihydroxyphenylacetic acid, 3-methoxy-4-hydroxyphenylethanol, and 3,4-dihydroxyphenylethanol. Deuterated analogs were used as internal standards. The method is fast, reproducible, sensitive, and selective, and does not require the use of time-consuming clean-up procedures. Normal excretion values in terms of creatinine, expressed as a function of age, as well as values obtained for patients with neurogenic tumors, a patient during therapy with L-3,4-dihydroxyphenylalanine, and a patient receiving dopamine are presented and discussed.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Muskiet FA,Fremouw-Ottevangers DC,van der Meulen J,Wolthers BG,de Vries JAsubject
Has Abstractpub_date
1978-01-01 00:00:00pages
122-7issue
1eissn
0009-9147issn
1530-8561journal_volume
24pub_type
杂志文章abstract：BACKGROUND:Variability among assays used to measure intact parathyroid hormone (iPTH) is of particular concern because of the routine use of iPTH assay results to guide management of osteodystrophy and calcium metabolism in patients with end-stage renal disease (ESRD). The aim of this study was to determine the extent ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.071589
更新日期：2006-09-01 00:00:00
abstract：BACKGROUND:The short half-life of the alpha-class glutathione S-transferases (GSTAs) in plasma combined with their even distribution throughout the liver lobule suggests that they may be useful complements to the more traditionally used liver markers. However, the currently available assays for measuring GSTAs in biolo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-05-01 00:00:00
abstract：:Biological variation is inherent in all medical tests and is a major source of error in clinical test interpretation. We use inherent test error due to biological variability as the touchstone by which to validate the clinical acceptability of analytical goals. Analytical goals should consist of sets of complementary ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1993-07-01 00:00:00
abstract：BACKGROUND:Evidence suggests that systemic inflammation may adversely impact HDL function. In this study we sought to evaluate the independent and incremental predictive performance of GlycA-a novel serum inflammatory biomarker that is an aggregate measure of enzymatically glycosylated acute phase proteins-and HDL subc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.261636
更新日期：2017-01-01 00:00:00
abstract：:We modified a one-step, two-site, double monoclonal immunoenzymometric assay (Abbott Laboratories) for serum alpha1-fetoprotein (AFP) to increase its sensitivity and improve test precision at the low end. We increased sample size, incubation interval, and reaction time and temperature, and decreased the final reaction...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-04-01 00:00:00
abstract：:We have developed an interactive statistical quality-control system for the small- to medium-sized radioimmunoassay laboratory, which can be used in a programmable desk-top calculator instead of the medium- or large-scale computer systems usually required. The design of this quality-control system is modeled after the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-07-01 00:00:00
abstract：:A colorimetric method for measuring anti-NAD+ glycohydrolase in human sera has been developed. The assay involves the inhibition of NAD+ glycohydrolase (EC 3.2.2.5) by the antibody and determination of the noninhibited enzyme activity by using an enzymatic amplifying system for NAD+. The assay is easily carried out an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-06-01 00:00:00
abstract：:In this method for serum and urinary urea determination, the same reagent is used without predilution of urine samples. The method is based on the pH increase resulting from the ammonia released by urease hydrolysis of urea. o-Cresolphthalein complexone is used to monitor the pH change colorimetrically. Urea concentra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-05-01 00:00:00
abstract：:Genetic engineering of beta-galactosidase (EC 3.2.1.23) has led to the development of a new homogeneous assay system, CEDIA. The Z gene of the lac operon of Escherichia coli encodes a large enzymatically inactive polypeptide that spontaneously aggregates and folds to form active beta-galactosidase. Using recombinant D...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-09-01 00:00:00
abstract：BACKGROUND:Simple, reproducible assays are needed for the quantification of sphingolipids, ceramide (Cer), and sphingoid bases. We developed an HPLC method for simultaneous quantification of total plasma concentrations of Cer, glucosylceramide (GlcCer), and ceramide trihexoside (CTH). METHODS:After addition of sphinga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.079012
更新日期：2007-04-01 00:00:00
abstract：BACKGROUND:Total prostate-specific antigen (tPSA) is flawed for prostate cancer (PCa) detection. [-2]proprostate-specific antigen (p2PSA), a molecular isoform of free PSA (fPSA), shows higher specificity compared with tPSA or percentage of free PSA (%fPSA). The prostate health index (Phi), a measure based on p2PSA and ...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2012.195784
更新日期：2013-01-01 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：:We compared the results obtained by a micromethod for the determination of plasma lipoprotein cholesterol, in which electrophoresis is used to separate the lipoprotein fractions (beta-, pre-beta-, and alpha-lipoproteins), with those determinations with ultracentrifugation (low-density, very-low-density, and high-densi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-10-01 00:00:00
abstract：:If there were enzymatically inactive B subunits in a solution containing lactate dehydrogenase (LD) B4 prepared from the hemolysates of heterozygous individuals with LD-B subunit deficiency, the inactive subunits would compete with normal subunits for antibodies to the B4 subunit. Using the activity of normal LD-B4 as...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：BACKGROUND:Human herpesvirus 6 (HHV-6) latently infects a majority of adults. In about 1% of the population HHV-6 exists in a chromosomally integrated form (ciHHV-6) that resides in every somatic and germ cell and can be transmitted through the germ line. Patients with ciHHV-6 have been misdiagnosed and unnecessarily t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.217240
更新日期：2014-05-01 00:00:00
abstract：:A new method for quantifying specific amino acids in small volumes of plasma and whole blood has been developed. Based on isotope-dilution tandem mass spectrometry, the method takes only a few minutes to perform and requires minimal sample preparation. The accurate assay of both phenylalanine and tyrosine in dried blo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-01-01 00:00:00
abstract：:Measurement of the mass concentration of serum enzymes by radioimmunoassay provides direct quantitation of specific isoenzymes and may be less subject to some of the limitations of traditional assay procedures for enzymes. We describe the development of a sensitive and specific radioimmunoassay for the muscle isoenzym...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-03-01 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：: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：: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：:Based on the quantitative determination of creatinine, total protein, albumin, alpha 1-microglobulin, IgG, alpha 2-macroglobulin, and N-acetyl-beta, D-glucosaminidase in urine in combination with a test strip screening, the findings of hematuria, leukocyturia, and proteinuria can be assigned to prerenal, renal, or pos...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-08-01 00:00:00
abstract：:We describe a direct radioimmunoassay for serotonin (5-hydroxytryptamine) in cerebrospinal fluid, platelet-poor plasma, and serum. We raised antisera in rabbits against serotonin diazotized to a conjugate of bovine albumin and D,L-p-aminophenylalanine. Polyethylene glycol, alone or in combination with anti-rabbit immu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：:We compared cyclosporine concentrations in whole blood as measured by HPLC and by RIA with a monoclonal antibody specific for cyclosporine with 3H- or 125I-labeled cyclosporine ligand. The 3H-RIA kit slightly underestimated cyclosporine concentrations (greater than 600 micrograms/L) in comparison with HPLC. Over a wid...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：BACKGROUND:Subfractions of HDL, particularly large HDL (HDL2), are inversely correlated with the severity of coronary artery disease (CAD). alpha-Tocopherol (AT) is the main lipid-soluble antioxidant in plasma. Results of a previous small study (n = 44) suggested that either a combination of an antioxidant cocktail [80...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
doi：10.1373/clinchem.2006.078865
更新日期：2007-03-01 00:00:00
abstract：BACKGROUND:We previously reported a family in which the propositus and both her father and paternal grandmother had high serum aminopeptidase N (CD13; EC 3.4.11.2) activity (autosomal dominant). The molecular mass of the serum CD13 polypeptide of the propositus was larger than that of normal CD13, suggesting either a m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-02-01 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 describe specific EMIT homogeneous enzyme immunoassays for amitriptyline, nortriptyline, imipramine, and desipramine in patients' serum samples. Before analysis, an easily performed extraction step involving the use of 500 microL of sample and a 1-mL disposable column eliminates cross-reacting polar metabolites. Th...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-05-01 00:00:00
abstract：:A polymorphism in the human prostate-specific glandular kallikrein (hKLK2) gene was described by direct sequencing (by PCR) of genomic DNAs isolated from prostatic cancer tissue, benign prostatic hyperplasia tissue, and blood leukocyte specimens. Results showed two forms of human prostate-specific glandular kallikrein...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-02-01 00:00:00
abstract：BACKGROUND:Stability of chemical speciation during sample handling and storage is a prerequisite to obtaining reliable results of trace element speciation analysis. There is no comprehensive information on the stability of common arsenic species, such as inorganic arsenite [As(III)], arsenate [As(V)], monomethylarsonic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-11-01 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
