Abstract:
:We describe an automated (ABA-100) enzymic method for determination of urinary oxalate by use of oxalate oxidase (EC 1.2.3.4) isolated from beet stems. The H2O2 produced by the oxidation of oxalate by oxalate oxidase is measured by coupling with oxidation and conjugation of 3-methyl-3-benzothiazolinone hydrazone with N,N-dimethylaniline with catalysis by horseradish peroxidase. The resulting indamine dye is measured spectrophotometrically by the difference in absorption at 500 and 600 nm. Interfering substances are removed by oxidation with acidic ferric chloride and by cation-exchange chromatography. The assay is sensitive to 5 mg of urinary oxalate per liter, the standard curve is linear to 70 mg/L, and the procedure requires less than 3 h for completion. The within-run CV was less than 1.6%, the between-day CV less than 5.6%. The oxalate oxidase method results in a mean and reference interval for oxalate excretion that are comparable with those by isotope dilution, gas-chromatographic, colorimetric, and other enzymic procedures.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Obzansky DM,Richardson KEsubject
Has Abstractpub_date
1983-10-01 00:00:00pages
1815-9issue
10eissn
0009-9147issn
1530-8561journal_volume
29pub_type
杂志文章abstract::We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-05-01 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:BACKGROUND:Direct equilibrium dialysis and direct ultrafiltration free thyroxine (T(4)) assays rely on semipermeable membranes to exclude T(4)-binding serum proteins from dialysates and ultrafiltrates. The presence of these proteins in dialysates or ultrafiltrates will yield spuriously high free T(4) values when free T...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.085316
更新日期:2007-05-01 00:00:00
abstract::The formal definition of sensitivity associates the term with the change in the response of a system for a small change of the stimulus causing the response, i.e., the ratio of the response of a system to the stimulus causing it. One interpretation of sensitivity associates the rate of change of the response for a sma...
journal_title:Clinical chemistry
pub_type: 评论,杂志文章
doi:
更新日期:1997-10-01 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::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:BACKGROUND:Δ(9)-Tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), and cannabinol (CBN) were measured in breath following controlled cannabis smoking to characterize the time course and windows of detection of breath cannabinoids. METHODS:Exhaled breath was collected from chronic (≥4 times per week) and occas...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.207407
更新日期:2013-12-01 00:00:00
abstract::We measured thyroid hormones and thyroxin-binding proteins in serum from 62 normal lactating and 52 nonlactating women at three months postpartum, and compared these values with those for 42 nonpregnant control women of similar age. Mean thyroxin concentrations in the lactating and nonlactating women were significantl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract::We studied the EMIT (Enzyme Multiplied Immunoassay Technique, Syva) procedures for the assay of phenytoin and phenobarbital in serum, adapting them to the miniature Centrifugal Fast Analyzer. For different concentrations of drug, each rate of reaction decreased continuously with time, tending to converge on a single c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-08-01 00:00:00
abstract::I describe a micro-scale method for determining lead in whole blood by utilizing a graphite furnace. Sample pretreatment consists of fivefold dilution with a dilute surfactant. The method is directly calibrated with lead standards prepared in dilute HNO3. To eliminate a small, nonspecific absorption signal from the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-04-01 00:00:00
abstract:BACKGROUND:Hyperlipidemia associated with the protease inhibitor (PI) component of highly active antiretrovial treatment can lead to accelerated atherosclerosis. The apolipoprotein A-V (APOA5) gene, which affects VLDL production and lipolysis, may play a role in PI-induced hyperlipidemia, particularly in individuals wi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.069583
更新日期:2006-10-01 00:00:00
abstract::The Dutch Foundation for Quality Assessment in Clinical Chemistry (SKZL) is the professional organization that conducts external quality-assessment schemes in The Netherlands. However, such schemes in fact assess the performance of the internal quality-control systems of the participating laboratories. In this paper w...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-07-01 00:00:00
abstract::We evaluated the analytical performance of Trinder's glucose oxidase (EC 1.1.3.4)/peroxidase (EC 1.11.1.7) 4-aminophenazone-phenol method for the quantification of serum glucose as adapted to the Technicon SMAC. Our results correlated well with those by the routine SMAC glucose oxidase/peroxidase 3-methyl-2-benzothiaz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-10-01 00:00:00
abstract:BACKGROUND:Reduced renal function is an established risk factor for cardiovascular events. We compared 3 measures of renal function--serum cystatin C, serum creatinine, and calculated creatinine clearance--as predictors of subsequent cardiovascular events in a community-based population of elderly individuals. METHODS...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.135962
更新日期:2010-05-01 00:00:00
abstract::A modified pentamer formation assay (PFA) for quantification of tacrolimus and active metabolites after extraction from whole blood is described. The lower limit of detection was 2 microg/L. Intraassay precision (CV) was 5.7-13.7%, and the interassay CV was 6. 1-14.9%. Tacrolimus trough concentrations in 104 whole blo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-12-01 00:00:00
abstract:BACKGROUND:Patients differ in responses to warfarin, which is commonly prescribed to treat thromboembolic events. Genetic variations in the cytochrome P450, family 2, subfamily C, polypeptide 9 (CYP2C9), vitamin K epoxide reductase complex, subunit 1 (VKORC1), and gamma-glutamyl carboxylase (GGCX) genes have been shown...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.118497
更新日期:2009-04-01 00:00:00
abstract::A study was undertaken to assess the short-term (intrapregnancy) and long-term (interpregnancy) variability of the 1-h 50-g oral glucose challenge test (GCT). Two groups of pregnant women had GCTs in consecutive pregnancies, 1 (n = 77) and 2 (n = 43) years apart. Their results were compared with published results for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-02-01 00:00:00
abstract::Four commercial products for urine glucose determination were evaluated and compared with a quantitative hexokinase procedure. We examined precision, sensitivity, and analytical recovery of glucose from glucose-supplemented urine samples and comparison of methods, using patients' samples. Only "Chemstrip uG" (Bio-Dyna...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract::The clinical utilities of the emerging biochemical markers for mammary adenocarcinoma CA 15-3, CA 549, CA M26, CA M29, and MCA (mucin-like carcinoma-associated antigen) were assessed by a formal rating according to six desirable marker characteristics. All five indicators similarly have good specificities but limited ...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1993-11-01 00:00:00
abstract::Various laboratories have reported endogenous digoxin-like immunoreactive factor(s) (DLIF) in blood from patients in renal failure or liver failure, from newborn infants, and from third-trimester pregnant women. Similar immunoreactivity has been detected in amniotic fluid, in cord blood, and in urine and serum from no...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1985-09-01 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:BACKGROUND:Because reference values for vitamin B(12) concentrations and vitamin B(12)-binding capacities for pregnant women have not been established, the reference values for nonpregnant women are often applied to assess vitamin B(12) status. The aim of the present study was to describe ranges of biochemical indices ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-06-01 00:00:00
abstract::A liquid-chromatographic technique with a post-column enzymatic reaction and fluorescence detection was validated for analysis of individual bile acids in the serum of rats. Extraction recoveries averaged 91.1% (SD 6.9%) for all bile acids. The assay was sensitive (minimum detection of 16.8 pmol per 100-microL injecti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::Single-spin density-gradient ultracentrifugation (DUC) has proven to be a reproducible method for detection of low-density-lipoprotein (LDL) heterogeneity. Recently another method has been described for this: gradient gel electrophoresis (GGE) of serum, a method that might be more suitable for screening. To gain insig...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-06-01 00:00:00
abstract:BACKGROUND:We explored the utility of multiplexed temperature gradient capillary electrophoresis (TGCE) as a screening tool for identifying genetic changes in the human mitochondrial genome. We examined changes in mitochondrial DNA (mtDNA) in nonmelanoma skin cancers (NMSCs), using TGCE to resolve genetic differences c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.040311
更新日期:2005-02-01 00:00:00
abstract::Red blood cell (RBC) replacement solutions are being developed as alternatives to allogeneic RBC use in blood transfusions in the treatment of massive trauma, to achieve hemodynamic stability during elective surgery, and to increase oxygen-carrying capacity in anemia. Hemoglobin-based oxygen carrier (HBOC)-201 (Biopur...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract:BACKGROUND:Iron may promote coronary atherosclerotic disease (CAD) by increasing lipid peroxidation. Studies on biochemical or genetic markers of body iron stores as risk factors for CAD have yielded conflicting results. METHODS:We studied 849 individuals with a clear-cut definition of the CAD phenotype, i.e., with (C...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-01-01 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::To evaluate a theoretical model for calculating free thyroid hormones, based on the law of mass action, we compared values for both calculated and measured free thyroxin and free triiodothyronine in a group of normal subjects. To determine whether the concentrations of circulating free hormones were also predictable f...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-06-01 00:00:00
abstract::alpha 1-Antitrypsin (A1AT) deficiency is a relatively common autosomal recessive disease, resulting most often from a single base pair (1 bp) substitution called the Z mutation. Previous genetic tests for carriers and affected patients have relied on quantitative binding of radioactive probes to an amplified gene prod...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00