Abstract：
:We describe the conjoint measurement in urine of the alcoholic catecholamine metabolites 3,4-dihydroxyphenylglycol (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG). The method involves extraction with ethyl acetate and back-extraction into acetic acid (MHPG), followed by adsorption onto alumina (DHPG). The separation is performed by reversed-phase liquid chromatography with column switching and amperometric detection. Total (free plus conjugated) compounds are determined after a 24-h enzymatic hydrolysis. Twelve-hour excretion values for normal and hypertensive subjects are given, together with results obtained for patients with pheochromocytoma, chemodectoma, and congenital dopamine-beta-hydroxylase deficiency. The assay is sensitive, reproducible, and free of interferences, and may lead to a better understanding of overall catecholamine metabolism in health and disease.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Julien C,Rodriguez C,Sacquet J,Cuisinaud G,Sassard Jsubject
Has Abstractpub_date
1988-05-01 00:00:00pages
966-9issue
5eissn
0009-9147issn
1530-8561journal_volume
34pub_type
杂志文章abstract：:A three-parameter model for directly estimating imprecision profiles from replicated immunoassay results is compared with a six-parameter indirect profile model obtained by the usual method of combining error in the raw response measurements with the slope of the standard curve. Direct estimation is likely to be less ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
abstract：:We evaluated the Reflotron (Boehringer Mannheim) system for measuring activities of alanine aminotransferase (EC 2.6.1.2) and gamma-glutamyltransferase (EC 2.3.2.2). Within- and between-day precision were comparable with conventional analytical methods. The linear range of the methods extended to more than 40-fold the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-06-01 00:00:00
abstract：:Both cellulose acetate electrophoresis and citrate agar electrophoresis were performed on 834 blood samples collected on filter paper in Jamaica and shipped for testing to the National Hemoglobinopathy Standardization Laboratory at the U.S. National Center for Disease Control. Additionally, 30 blood samples collected ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-05-01 00:00:00
abstract：:To demonstrate oligoclonal IgG bands (I) in unconcentrated cerebrospinal fluid, we used isoelectric focusing in agarose followed by protein transfer to cellulose nitrate membrane, double-antibody peroxidase labeling, and avidin-biotin amplification. I can be reliably seen after isoelectric focusing of 5-microL specime...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-07-01 00:00:00
abstract：:We describe a time-resolved immunofluorometric assay (IFMA) for corticotropin in unextracted human plasma, based on the use of two monoclonal antibodies: europium-labeled antibody 1A12 and antibody 2A3 coated onto microtiter wells. We compared the results of this assay with those of an immunoradiometric assay (IRMA) p...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：BACKGROUND:Human iron status is influenced by environmental and genetic factors. We hypothesized that the genetic polymorphism of haptoglobin (Hp), a hemoglobin-binding plasma protein, could affect iron status. METHODS:Reference values of serum iron status markers were compared according to Hp phenotypes (Hp 1-1, Hp 2...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-10-01 00:00:00
abstract：:Using Syva "EMIT" reagents and the Cobas Bio centrifugal analyzer, we have developed cost-effective assays for therapeutic drug monitoring of carbamazepine, phenobarbital, and phenytoin. With these optimized methods one can assay up to 2470 samples with a single 100-test EMIT kit with good precision and accuracy. Betw...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
abstract：:We conducted a proficiency survey of cholesterol and high-density lipoprotein (HDL) cholesterol analysis in local clinical laboratories to determine whether increased national emphasis on cholesterol measurement had resulted in changes in performance from previous surveys. Sets of frozen aliquots of plasma and HDL sup...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
abstract：BACKGROUND:Few data compare cardiac troponin T (cTnT) and cardiac troponin I (cTnI) in a general population. We sought to evaluate the distribution and association between cTnT, cTnI, and cardiovascular risk factors in a large general population cohort. METHODS:High-sensitivity cTnT and cTnI were measured in serum fro...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2018.292086
更新日期：2018-11-01 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 apolipoprotein A-I (apo A-I) radioimmunoassay established in our laboratory involves use of purified apo A-I as the primary standard for quantifying apo A-I in plasma and a pooled plasma (quality-control sample) as a secondary standard to decrease interassay variation. The measured values for apo A-I increased ove...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-07-01 00:00:00
abstract：BACKGROUND:A substantial proportion of the variability in the absorption and clearance of cyclosporin A (CsA) after oral administration has been attributed to variability in liver cytochrome P-450 3A4 (CYP3A4) activity and intestinal P-glycoprotein (P-gp) concentration. A polymorphism in the CYP3A4 promoter region, ter...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-06-01 00:00:00
abstract：BACKGROUND:Previous studies have shown a single linear relationship between mean plasma glucose (MPG) and hemoglobin A(1c) (HbA(1c)). We examined the relationship in different treatment groups of patients with type 1 diabetes participating in the Diabetes Control and Complications Trial (DCCT). METHODS:Seven-point glu...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
doi：10.1373/clinchem.2006.079756
更新日期：2007-05-01 00:00:00
abstract：:Analytical, intra-individual, and interindividual components of variation have been determined for pH, pCO2, bicarbonate, base excess, and total CO2 in capillary specimens of whole blood from a cohort of 14 healthy subjects. Calculated analytical goals (SD) are pH less than or equal to 0.008, pCO2 less than or equal t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-08-01 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：BACKGROUND:Although lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels are associated with cardiovascular events, Lp-PLA(2) is physically linked to LDL cholesterol (LDL-C). Whether measures of Lp-PLA(2) mass or activity continue to predict risk after LDL-C reduction by statin therapy is uncertain. METHODS:Lp...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.180281
更新日期：2012-05-01 00:00:00
abstract：BACKGROUND:The susceptibility of plasma lipids to oxidation is thought to be a factor contributing to atherogenic risk. Various groups have studied the in vitro oxidizability of isolated LDL and examined the effects of conventional antioxidants. The drawbacks associated with the isolation of LDL for evaluation of in vi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.051078
更新日期：2005-11-01 00:00:00
abstract：:I determined the in vitro biological half-lives or decay constants for creatine kinase isoenzymes at various temperatures. Values at 37 degrees C are consistent with values reported by others in vivo, which suggests that in vivo irreversible inactivation is primarily thermal. Reversible inactivation appears to be an o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:To see if saliva is a valid substitute for plasma in assay of progesterone even when concentrations of hormone and binding proteins are fluctuating, we determined the concentrations of total and free progesterone in plasma and salivary progesterone in specimens from 36 women volunteers during the course of pregnancy a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：:Six different procedures for radioiodination of mouse epidermal growth factor (EGF) all resulted in a heterogeneous 125I-labeled EGF preparation, as analyzed by reversed-phase HPLC. EGF preparations that had been iodinated with Chloramine T, lodogen, or lodo-beads were found mainly to consist of oxidized 125I-labeled ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-05-01 00:00:00
abstract：:A rapid technique (5-10 min) has been developed for fractionating nucleotides from base and nucleoside contaminants in acid extracts of cells, by adsorption to silica gels. Silica gels (1-mL bed volume) were washed with 5 mL of water then with 5 mL of acetonitrile/water (90/10 by vol). After applying 3-mL samples, adj...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-09-01 00:00:00
abstract：BACKGROUND:Adequate detection of designer steroids in the urine of athletes is still a challenge in doping control analysis and requires knowledge of steroid metabolism. In this study we investigated whether uPA(+/+)-SCID mice carrying functional primary human hepatocytes in their liver would provide a suitable alterna...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.119396
更新日期：2009-10-01 00:00:00
abstract：:We studied the pattern of acute-phase proteins (orosomucoid, C-reactive protein, and haptoglobin) in hepatocellular deficiency due to chronic alcohol consumption, characterized by a decrease in serum transferrin concentration. We found that their patterns could vary independently of hepatocellular deficiency, but depe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-01-01 00:00:00
abstract：:The aim of this investigation was to study the distribution of arsenic species in human organs following fatal acute intoxication by arsenic trioxide. The collected autopsy samples of most organs were ground and dried, and the total arsenic was measured by electrothermal atomic absorption spectrometry (ETAAS). The ars...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-02-01 00:00:00
abstract：BACKGROUND:Hyperhomocysteinemia (HHcy) has been linked to impaired left ventricular function and clinical class in patients with chronic heart failure. We hypothesized that HHcy stimulates myocardial brain natriuretic peptide (BNP) expression and induces adverse left ventricular remodeling. METHODS:We randomized 50 ra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.077859
更新日期：2007-04-01 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：BACKGROUND:Several plasma proteins have been suggested as markers for a variety of cardiovascular conditions but fail to qualify in independent patient cohorts. This may relate to interference of medication on plasma protein concentrations. We used proteomics to identify plasma proteins that changed in concentration wi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2017.282665
更新日期：2018-10-01 00:00:00
abstract：:A fixed-time incubation method for measuring acetylsalicylic acid esterase was improved by using a higher concentration of the substrate, acetylsalicylic acid, and an activator, Ca2+. The enzymatic activity in serum was 25-fold that measured by earlier methods. Inhibition studies showed a pattern similar to that repor...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:Agarose column chromatography has been used to separate plasma lipoproteins into very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Applied to the diagnosis of primary type III hyperlipoproteinemia, the procedure is capable of demonstrating three characteristic an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-12-01 00:00:00
abstract：:We have assessed Calbiochem single-vial enzymatic reagent systems for the analysis for cholesterol and triglycerides, using manual and centrifugal analyzer techniques. Analysis for cholesterol by both techniques had acceptable performance by the short-term criteria of the Center for Disease Control (CDC) during this s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-11-01 00:00:00
