Abstract：
:Methods are described for detection of lactate dehydrogenase (LDH) inhibitors in preparations of reduced nicotinamide adenine dinucleotide. They are (a) comparison of values by kinetic methods with those measured for highly purified NADH and (b) examination of Lineweaver-Burk plots. Chromatographic inhomogeneities are correlated with deviant values for the kinetic constants of NADH preparations. Lineweaver-Burk plots that curve upward at the high concentrations or have a larger or smaller than normal slope may indicate the presence of inhibitor. As determined in bicarbonate buffer (0.11 mol/liter, pH 7.9) by use of 0.600 mmol/liter pyruvate and NADH freshly separated from impurities by chromatography on diethyl-aminoethyl-cellulose, the Km (apparent) of NADH at 25 degrees C has the value 8.11 +/- 0.71 mumol/liter (SD, n = 28) with LDH-1 (pig heart, 2.48 +/- 0.05 U per milliliter of reaction mixture, or 41.3 +/- 0.8 nmol/liter per second). Under similar conditions, the Km (apparent) of NADH has the value of 8.57 +/- 1.58 mol/liter (SD, n = 21) with LDH-5 (pig muscle, 1.77 +/- 0.03 U/ml of reaction mixture), or 29.4 +/- 0.6 nmol/liter per second). At infinite substrate concentrations with the same pH, buffer, and temperature, the Km (apparent) for NADH was 26.0 +/- 0.63 mumol/liter with LDH-1 and 23.2 +/- 4.6 mumol/liter with LDH-5.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Howell BF,Margolis S,Schaffer Rsubject
Has Abstractpub_date
1976-10-01 00:00:00pages
1648-54issue
10eissn
0009-9147issn
1530-8561journal_volume
22pub_type
杂志文章abstract：:To secure a successful product in today's era of cost containment, manufacturers and developers of new in vitro diagnostic technologies must consider payment issues--coverage and reimbursement by healthcare insurers--as critical market forces that must be addressed in the business plan. Similar to the regulatory hurdl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-09-01 00:00:00
abstract：:We examined the mechanism by which hypertriglyceridemia interferes with the Roche Diagnostics "Amylochrome" procedure for measurement of amylase in lactescent samples with normal and above-normal amylase activity. The serum blank recommended in the Amylochrome protocol to compensate for lactescence remains inappropria...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-10-01 00:00:00
abstract：:Erythrocyte protoporphyrin content is increased in several human and veterinary disorders in which heme synthesis is disrupted. The nature of the defect determines whether zinc protoporphyrin, unchelated (free) protoporphyrin, or both are present in the erythrocytes. Extraction of the protoporphyrin into acetone/water...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-02-01 00:00:00
abstract：:We used gas chromatography-mass spectrometry to analyze serum specimens from a patient whose metabolic ketoacidosis resulted from sniffing a toluene-containing substance; we also analyzed a sample of the abused substance itself and a serum specimen from a normal subject. The blood samples from the patient showed abnor...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
abstract：:To correct the results of a radioimmunoassay for beta-thyrotropin (TSH) subunit by eliminating the proportion ascribable to intact TSH, we have devised a method that experimentally reproduces the conditions under which the interference develops. Beta-TSH subunit was assayed in several preparations containing known con...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-05-01 00:00:00
abstract：BACKGROUND:Epidemiologists have observed that blood donation is associated with decreased risk of type 2 diabetes and cardiovascular disease. METHODS:We investigated the relationship between iron stores and insulin sensitivity, after controlling for known confounding factors, and compared insulin sensitivity between b...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.046847
更新日期：2005-07-01 00:00:00
abstract：:We evaluated a method for quantifying high-density lipoprotein cholesterol in plasma, based on electrophoretic migration of the prestained (with Sudan Black III) sample through a discontinuous polyacrylamide++ gel and densitometric integration of the stain associated with each class of lipoprotein. With this method, o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-11-01 00:00:00
abstract：BACKGROUND:Intraventricular hemorrhage (IVH) is a major cause of neurologic disabilities in preterm newborns. We evaluated the use of plasma activin A concentrations to predict the development of perinatal IVH. METHODS:We measured nucleated erythrocyte (NRBC) counts, plasma activin A, hypoxanthine (Hyp), and xanthine ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.065979
更新日期：2006-08-01 00:00:00
abstract：:Currently, we can make the following generalizations about the major long-term complications of diabetes. First, they occur commonly after 10 to 15 years of diabetes. Second, the complications of renal and retinal disease, but not of atherogenic and neurological disease, appear to be related to the severity of hypergl...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,评审
doi：
更新日期：1986-10-01 00:00:00
abstract：:We directly estimated plasma aldosterone radioimmunologically with use of an antiserum raised against an aldosterone-3-oxime/bovine serum albumin conjugate, the estimation being on samples with and without heating (60 degrees C), and diluted and undiluted. Values so obtained were compared with those by radioimmunoassa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-01-01 00:00:00
abstract：:Sensitivity, stability, and specificity of the color-producing reaction of hydrogen peroxide with bezidine, leuco-malachite green, or o-dianisidine were tested in numerous systems containing hemoglobin and other hemoproteins. Use of urea or low temperature (to minus 12 degrees C), or both, was highly beneficial, espec...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
abstract：BACKGROUND:Reports of the use of multiplex enzyme assay screening for Pompe disease, Fabry disease, Gaucher disease, Niemann-Pick disease types A and B, and Krabbe disease have engendered interest in the use of this assay in newborn screening. We modified the assay for high-throughput use in screening laboratories. ME...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.104711
更新日期：2008-10-01 00:00:00
abstract：:We describe a mechanized chromogenic assay for factor X, the results of which correlate well with those for the one-stage clotting assays for factor X in which it is activated either via the extrinsic pathway by thromboplastin or directly by Russell's viper venom. We purified human factor X and raised monospecific ant...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-06-01 00:00:00
abstract：:A number of immunological techniques--radioimmunoassay, enzyme-linked immunosorbent assay (ELISA), electroimmunoassay, radial immunodiffusion, and a variety of immunoprecipitin assays--have been used to quantify apolipoproteins in plasma. This paper outlines their technical details and discusses their major advantages...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1990-04-01 00:00:00
abstract：:Serum specimens from patients on primidone therapy were assayed by two currently available procedures: a commercially available enzyme immunoassay (EMIT) and a published gas-chromatographic procedure. Both procedures were done with commercially available materials and equipment. Results by the two procedures agreed we...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-06-01 00:00:00
abstract：BACKGROUND:In recent years, a large number of studies have been published on the performance of glucose monitors. The quality of these reports is not known. METHODS:We searched the PubMed database for performance evaluations of handheld glucose monitors published from August 2002 to November 2006. Relevant articles we...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2006.083493
更新日期：2007-06-01 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：:This improved assay of rheumatoid factors in serum, described here for use with the Baker "Encore" centrifugal analyzer, is efficient, with 250-sample throughput per hour; reproducible, with between-batch CV = 5% and within-batch CV = 2% (mid-assay range); and results correlate well (r = 0.9) with those by other metho...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-02-01 00:00:00
abstract：:I describe a gas-chromatographic procedure involving a nitrogen detector for "free" (or "unbound") phenytoin in the concentration range 0.2-4.0 mg/L in ultrafiltrates of plasma. The CV (n = 10) for the assay was 2.9% for a 0.49 mg/L concentration, 1.5% for 2.02 mg/L. The sensitivity was 0.05 mg/L. The ultrafiltration ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-03-01 00:00:00
abstract：BACKGROUND:Screening for heterozygous sequence changes in PCR products, also known as "mutation scanning", is an important tool for genetic research and clinical applications. Conventional methods require a separation step. METHODS:We evaluated the sensitivity and specificity of homogeneous scanning, using a saturatin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.029751
更新日期：2004-10-01 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：:Measurement of acetaminophen by analysis of the second derivative of its spectrum is specific and sensitive. The method of extraction and the use of just one phosphate buffer as reagent makes this method very convenient. Readings are reliable from 10 to 1500 mg/L. A turnaround time of 20 min makes this method well sui...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
abstract：:In this method for measuring amino acids in urine, serum, and tissue, the amino acids to be assayed and the internal standard, L-norleucine, are converted to phenylthiohydantoins , isolated by organic solvent extraction, separated by reversed-phase "high-pressure" liquid chromatography, and detected by ultraviolet abs...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-06-01 00:00:00
abstract：:In the disposable rotor of the SAM microcentrifugal analyzer, various lyophilized reagents are predistributed in 24 33-microL cuvets, for determination of multiple analytes in one specimen (e.g., for patient profiles). We evaluated a prototype of this system, which can be used at 25, 30, or 37 degrees C; absorbance re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-09-01 00:00:00
abstract：:Using image-analyzing equipment, we measured the effect of quinidine on the activity of naphthol AS-D chloroacetate esterase, alpha-naphthyl butyrate esterase, alpha-naphthyl acetate esterase, and acid phosphatase in individual cells of a human Hep G2 hepatoma cell line. The impact of the drug on the morphology of the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-03-01 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:Pompe disease (PD) is the first lysosomal storage disorder to be added to the Recommended Uniform Screening Panel for newborn screening. This condition has a broad phenotypic spectrum, ranging from an infantile form (IOPD), with severe morbidity and mortality in infancy, to a late-onset form (LOPD) with vari...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.259036
更新日期：2017-04-01 00:00:00
abstract：:We report the production and comparative specificities of antisera raised to different immunogens containing codeine, morphine, and oxycodone. Antisera raised to bovine serum albumin (BSA) conjugates of codeine-6-hemisuccinate, ethylmorphine-6-hemisuccinate, or oxycodone-6-carboxymethyloxime had greatest recognition o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-09-01 00:00:00
abstract：:The molar absorptivity of unconjugated bilirubin in caffeine reagent is independent of the protein matrix. This finding, together with the simplicity of a dilution step for direct spectrophotometry, will improve the calibration methods of bilirubin and make them more nearly accurate. This is encouraging for the develo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-07-01 00:00:00
abstract：:In assessing interference from bilirubin, the use of a synthetic soluble derivative (ditaurobilirubin, DTB) is recommended as a surrogate for the natural conjugates (Bc). We compared the interference effect of unconjugated bilirubin (Bu), Bc, and DTB, using six mechanized methods for serum creatinine measurement. No s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-02-01 00:00:00
