Abstract:
:We describe specifications for high-purity 4-nitrophenol, which is suitable for spectrophotometric standardization. Such a reference material is needed in clinical enzymology to establish the proper molar absorptivity of 4-nitrophenol under final reaction conditions, particularly for measuring alkaline phosphatase activity in human serum. Some lots of 4-nitrophenol available commercially met these specifications, but several did not. The latter can be purified to meet our specifications by recrystallization or sublimation. The molar absorptivity of 4-nitrophenol (35 mumol/L) IN 10 mmol/L NaOH at 25 degrees C at 401 nm is 18380 +/- 90 L.mol-1.cm-1.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Bowers GN Jr,McComb RB,Christensen RG,Schaffer Rsubject
Has Abstractpub_date
1980-05-01 00:00:00pages
724-9issue
6eissn
0009-9147issn
1530-8561journal_volume
26pub_type
杂志文章abstract::We measured glucocorticoid receptors (GR) in mononuclear leukocytes (MNL) isolated from peripheral blood of 145 apparently healthy volunteers (86 men and 59 women). An age-related decrease in the number of GR was suggested between subjects younger than 20 years and elderly subjects; there was no apparent seasonal vari...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-10-01 00:00:00
abstract:BACKGROUND:alpha(1)-Antitrypsin is the major plasma serine protease inhibitor. Its deficiency is mainly associated with the alleles PI*S and PI*Z and can lead to obstructive lung disease in adults and to liver cirrhosis during childhood. METHODS:A multiplex PCR method has been established that uses two sets of primers...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2000-02-01 00:00:00
abstract::Detection of intracellular antigens by flow cytometry requires effective fixation and permeabilization of the cell membrane. This study compares three fixation/permeabilization techniques: two commercial chemical reagents, the ORTHOPermeaFix (OPF) and the FIX&PERM Cell Permeabilization Kit (F&P), and a novel method ba...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-11-01 00:00:00
abstract::In photometry, where both the product formed and one or several reactants absorb light at the same wavelength, the absorbance of the "blank" of the sample at the end of the reaction may be less than that measured at the beginning of the reaction, because of consumption of reactant(s). The blank correction factor for t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-03-01 00:00:00
abstract::We report the accuracy, imprecision, total analytical errors, and patient misclassification errors for cholesterol measured from capillary whole blood, venous whole blood, and venous plasma samples by five devices used in public cholesterol screening environments: Reflotron, Vision, Ektachem DT-60, QuickRead, and Lipo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-02-01 00:00:00
abstract:BACKGROUND:Mitochondrial diseases are clinically and genetically heterogeneous, with variable penetrance, expressivity, and differing age of onset. Disease-causing point mutations and large deletions in the mitochondrial genome often exist in a heteroplasmic state. Current molecular analyses require multiple different ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.181438
更新日期:2012-09-01 00:00:00
abstract::In this liquid-chromatographic method for the determination of bromide in human serum, an important and unique feature is pre-analysis ultrafiltration of the sample, which effectively removes proteins. The chromatographic system consists of an anion-exchange column (Whatman Partisil SAX 10-micron particles), an isocra...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-05-01 00:00:00
abstract:BACKGROUND:Several proteolytically derived fragments from the proline-rich region (PRR) of human inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) have been identified by surface-enhanced or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS or MALDI-TOF-MS) as potential diseas...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.065722
更新日期:2006-06-01 00:00:00
abstract::Hemoglobinometry according to the International Committee of Standardization in Hematology (ICSH) suffers from imprecision related to high sample dilution and from potential errors owing to sample turbidity. We have evaluated a new instrument, "HemoCue," that measures hemoglobin at two wavelengths as azide methemoglob...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-03-01 00:00:00
abstract::We evaluated five quantitative, commercially available radioimmunoassay methods (Beta-Tec, BIO-RIA, Cambridge Nuclear, Mallinckrodt, and Serono) for rapid determination of the beta-subunit of human choriogonadotropin in serum or plasma. Only three of the kits (Beta-Tec, Mallinckrodt, and Serono) were found suitable fo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-12-01 00:00:00
abstract::Humans are exposed daily to low concentrations of many different chemical substances, natural and some man-made. Although many of these substances can be toxic at high levels, typical exposures are far below the effect levels. The responses produced by man-made aromatic hydrocarbon receptor agonists, such as dioxins, ...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1996-08-01 00:00:00
abstract::Fast lipoprotein chromatography (FLPC) is a novel method for quantifying lipoproteins. Plasma proteins are separated by fast-flow gel filtration. Lipoproteins are detected by post-column derivatization with an enzymatic cholesterol reagent. FLPC resolves very-low-, low-, and high-density lipoproteins (VLDL, LDL, and H...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-11-01 00:00:00
abstract::We measured the concentration of erythrocyte protoporphyrin in 43 blood samples by two fluorometric methods. In the indirect method, protoporphyrin was extracted from blood and the fluorescence of the free acid in the extract was determined with a filter-fluorometer. These results were compared with results of direct ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-09-01 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::The main developments in the "ligand assay" field in which I have been involved are traced. These include the original development of "first generation" competitive assays relying on radiolabeled analyte markers; the development of the first "second generation", noncompetitive (ultrasensitive) methods, which rely on t...
journal_title:Clinical chemistry
pub_type: 历史文章,杂志文章
doi:
更新日期:1998-09-01 00:00:00
abstract::We describe a convenient, economical procedure for measuring uroporphyrinogen I synthase (EC 4.3 1.8) activity in erythrocytes, the results of which can be used to diagnose acute intermittent porphyria, in either its latent or acute stage. By limiting the test reaction sequence to the conversion of porphobilinogen to ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-07-01 00:00:00
abstract::The clinical value of measuring concentrations of methylmalonic acid in serum (S-MMA) as an aid in the diagnosis of cobalamin deficiency has recently aroused interest. In 58 healthy subjects, ages 40-68 years, we found a 0.95 reference interval of 0.05-0.37 mumol/L (mean 0.21, SD 0.094). In 33 of the subjects, who wer...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-07-01 00:00:00
abstract:BACKGROUND:Cleavage of conjugates is an important step in toxicological analysis, especially of urine samples. The aim of this study was to combine the advantages and to reduce the disadvantages of acid hydrolysis and conventional enzymatic hydrolysis procedures. METHODS:beta-Glucuronidase (GRD; EC 3.2.1.31) and aryls...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::We compared the analytical performance of the Kodak Ektachem XR700 assays of iron (Fe) and total iron-binding capacity (TIBC) with that of a conventional ferrozine assay (performed with a Cobas-Bio) and occasionally with that of atomic-absorption spectrometry (AAS). The correlation was modest between Kodak and Cobas-B...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-10-01 00:00:00
abstract::We studied the recently developed Abbott fluorescence polarization immunoassay (FPIA) for amphetamine and methamphetamine in urine and compared the results with those of the Syva enzyme-multiplied immunoassay technique (EMIT) and a gas-chromatographic assay. The FPIA method showed a limit of quantification of 0.3 mg/L...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract:INTRODUCTION:Parathyroid hormone-related peptide (PTHrP) is involved in activating pathways, allowing tumor cells to form bone metastases. Measurement of PTHrP is used for the diagnosis and clinical management of patients suspected of hypercalcemia of malignancy. We developed an LC-MS/MS method for measuring PTHrP, est...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.244012
更新日期:2016-01-01 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::Estimation of plasma catecholamine concentrations by "high-performance" liquid chromatography, although increasingly used, still presents difficulties. We describe a method for clean-up of plasma samples on cation-exchange resin before they are extracted with alumina. This procedure eliminates many of the interfering ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-07-01 00:00:00
abstract:BACKGROUND:To address the continuing need for the standardization of clinical human cardiac troponin I (cTnI) assays, NIST, with the assistance of the AACC/IFCC Cardiac Troponin I Standardization Committee, has developed a new certified reference material, Standard Reference Material (SRM) 2921: Human Cardiac Troponin ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.051359
更新日期:2006-02-01 00:00:00
abstract:BACKGROUND:Atherosclerosis is a complex, chronic disease that usually arises from the converging action of several pathogenic processes, including hypertension, hyperlipidemia, obesity, and the accumulation of oxidized LDL. Platelet-activating factor acetylhydrolase (PAF-AH) is a LDL- and HDL-bound enzyme that hydrolyz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.036863
更新日期:2004-11-01 00:00:00
abstract::This procedure for routine quantification of albumin in urine is based on the dye-binding properties of albumin with bromphenol blue. The absorbance of 100 microL of urine mixed with 3 mL of color reagent is measured against blank reagent at 610 nm after 30 s. Results vary linearly with albumin concentration up to 6 g...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-02-01 00:00:00
abstract::We compared the performance of three methods for quantifying high-density lipoprotein cholesterol (HDL-C) with the Reference Method for HDL-C, using samples with a wide range of triglyceride (TG) concentrations (290-18000 mg/L). All three comparison assays-- utilizing a magnetic dextran sulfate precipitating reagent, ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-05-01 00:00:00
abstract:BACKGROUND:Multiplexed amplicon melting is a closed-tube method for genotyping that does not require probes, real-time analysis, asymmetric PCR, or allele-specific PCR; however, correct differentiation of homozygous mutant and wild-type samples by melting temperature (T(m)) analysis requires high-resolution melting ana...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.097121
更新日期:2008-01-01 00:00:00
abstract::Antithrombin III (AT III) activity was determined with two different new chromogenic substances--Chromozym-TH (Tos-Gly-Arg-p-nitroanilide; Boehringer Mannheim) and alpha-N-carbobenzyl-oxy-L-lysine-thiobenzyl ester (Du Pont)--with both a discrete (aca) and a centrifugal analyzer (COBAS BIO). The correlation between the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-11-01 00:00:00
abstract::Serial results from an individual are often obtained using more than one method. Results should be transferable over time and locale. Every method has inherent analytical error, and goals are required to delineate the maximum allowable random (imprecision) and systematic (inaccuracy, bias) errors to facilitate optimal...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1992-11-01 00:00:00