Abstract:
:Optimal reaction conditions for assaying human lactate dehydrogenase pyruvate-to-lactate were determined for isoenzymes 1 and 5 at 25, 30, and 37 degrees C. Three of the nine different buffers examined--imidazole, triethanolamine, and N-tris(hydroxymethyl)-methyl-2-aminoethane sulfonic acid--are satisfactory. Beta-NADH, pyruvate, and hydrogen ion concentrations were chosen to measure both isoenzymes with maximal-equal-sustainable efficiency at the lowest substrate concentrations. Approximately 95% of each isoenzyme is measured, for activities up to threefold the upper normal limit, if the measurements are made immediately after the reaction is initiated. The Arrhenius relationship for each isoenzyme is unique. Interconversion of results from one temperature to another is practical only with reservations. Results at 37 degrees C are not as reliable as those at 25 degrees C.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Buhl SN,Jackson KY,Graffunder Bsubject
Has Abstractpub_date
1978-02-01 00:00:00pages
261-6issue
2eissn
0009-9147issn
1530-8561journal_volume
24pub_type
杂志文章abstract:BACKGROUND:Neuroblastoma is the most common extracranial malignant solid tumor in children under 5 years and is characterized by a wide clinical and biological heterogeneity, from spontaneously regressive forms to cancers with a rapid and fatal progression. MYCN oncogene amplification is considered the most important p...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-11-01 00:00:00
abstract:BACKGROUND:Although microRNAs (miRNAs) play essential roles in spermatogenesis, little is known about seminal plasma miRNAs in infertile men. We investigated the profile of seminal plasma miRNAs in infertile men to identify miRNAs that are altered in infertility; we then evaluated their diagnostic value. METHODS:Semin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.169714
更新日期:2011-12-01 00:00:00
abstract::Diminished ability to utilize acetate (acetate intolerance) developed in a male patient on chronic hemodialysis after five years of maintenance dialysis. His ability to utilize lactate was also subnormal. We studied acetate metabolism in vitro by isolating lymphocytes from the patient's blood before dialysis and measu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-03-01 00:00:00
abstract::Ethchlorvynol is a commonly abused sedative hypnotic. I report here a seven-day study of serum ethchlorvynol concentrations in a patient who had received an extreme overdose. These concentrations were correlated with the patient's response to stimuli. Serum ethchlorvynol concentrations were logarithmically related to ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-06-01 00:00:00
abstract::Synovial fluid samples were collected from 45 patients with rheumatoid arthritis, spondylarthropathy, or osteoarthritis, to study their content of elastase (EC 3.4.21.37) and of cysteine proteinases (EC 3.4.22.1, 3.4.22.15). We measured both elastase complexed with alpha 1-proteinase inhibitor and elastase activity to...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract:BACKGROUND:In 2008, the US Food and Drug Administration (FDA) issued a Guidance for Industry statement formally recognizing (during drug development) the conjoined nature of type 2 diabetes (T2D) and cardiovascular disease (CVD), which has precipitated an urgent need for panels of markers (and means of analysis) that a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.156976
更新日期:2011-05-01 00:00:00
abstract::The diagnosis of thyroid disease now often can be achieved reliably by measuring thyrotropin (TSH) alone. Thyroxine (T4), triiodothyronine, and other analytes are only needed if TSH and the accompanying clinical condition are discordant. We describe here work that confirms the age independence of TSH in both inpatient...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-11-01 00:00:00
abstract:BACKGROUND:Prostate-specific antigen (PSA) is an important marker for the diagnosis and management of prostate cancer, and the free PSA/total PSA ratio has been shown to be efficient for distinguishing prostate cancer from benign prostatic hyperplasia. We report here the characterization of seven mouse monoclonal antib...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1999-05-01 00:00:00
abstract::We describe a rapid polarization fluoroimmunoassay for screening for the presence of barbiturates in urine. The single reagent is prepared by pre-mixing antiserum with a fluorescein-labeled barbiturate derivative as tracer. Use of a mixture of two sheep antisera, raised against different barbiturate immunogens, result...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-11-01 00:00:00
abstract::Abnormal creatine kinase (CK) isoenzyme patterns were observed in the serum of a 64-year-old woman with severe heart disease. Agarose electrophoresis revealed the presence of all the usual CK isoenzymes (MM, MB, and BB) plus an extra band between MM and MB. Total serum CK activity was within the normal range. Within 2...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract::This rapid radioimmunoassay for aldosterone is performed directly on 100 microL of unprocessed plasma, with 125I-labeled aldosterone as the labeled antigen. Our use of steroid-free plasma in preparing the standard curve resulted in an overestimate of aldosterone; this problem was overcome by adding to such plasma a mi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-02-01 00:00:00
abstract::We have developed two methods for determining serum concentrations of felbamate, a new anticonvulsant drug. The first method is based on protein precipitation with acetonitrile, followed by HPLC. The between-run CV for this method is 5.7% (mean 55 mg/L), and the linearity extends from 5 to 175 mg/L. Results by this me...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-10-01 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 have separated serum proteins in only 15 min by high-performance liquid chromatography. The identification of several peaks in the chromatographic profile was greatly aided by the use of multiple-wavelength detection. We have found a good correlation between retention times and electrophoretic mobilities. Serum sam...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-09-01 00:00:00
abstract:BACKGROUND:Cardiac troponin T (cTnT) is the preferred biomarker for the diagnosis of acute myocardial infarction (AMI). It has been suggested that cTnT is present predominantly in fragmented forms in human serum following AMI. In this study, we have used a targeted mass spectrometry assay and epitope mapping using West...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.261511
更新日期:2017-02-01 00:00:00
abstract:BACKGROUND:Different technologies, such as quantitative real-time PCR or microarrays, have been developed to measure microRNA (miRNA) expression levels. Quantification of miRNA transcripts implicates data normalization using endogenous and exogenous reference genes for data correction. However, there is no consensus ab...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2015.239459
更新日期:2015-11-01 00:00:00
abstract::Autocorrelation of clinical chemistry quality-control (Q/C) measurements causes one of the basic assumptions underlying the use of Levey-Jennings control charts to be violated and performance to be degraded. This is the requirement that the observations be statistically independent. We present a proposal for a new app...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-07-01 00:00:00
abstract::We describe a sensitive method for the determination of vanadium in biological substances by atomic absorption spectroscopy. By using background correction and pyrolytically coated graphite tubes with flameless apparatus, this vanadium assay has a sensitivity of 65 pg and a detection limit of 30 pg, approximately sixf...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-01-01 00:00:00
abstract:BACKGROUND:C-Reactive protein (CRP) has been shown to be a strong predictor of coronary heart disease (CHD) and is being considered in cardiovascular disease risk assessment. The number of normolipidemic individuals who are eligible for evaluation of CRP in overall CHD risk assessment is not known. METHODS:We analyzed...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.036004
更新日期:2004-09-01 00:00:00
abstract::Circadian variations of alanine aminopeptidase (EC 3.4.11.2), gamma-glutamyltransferase (EC 2.3.2.2), and N-acetyl-beta-glucosaminidase (EC 3.2.1.30) in urine were studied in 10 healthy children, ages six to 15 years. Urine specimens were collected during 24 h, grouped into four time intervals. Enzymes were measured s...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-05-01 00:00:00
abstract:BACKGROUND:Recurrent pregnancy loss, (RPL) affecting 1%-2% of couples, is defined as ≥3 consecutive pregnancy losses before 20-week' gestation. Women with RPL are routinely screened for etiological factors, but routine screening of male partners is not currently recommended. Recently it has been suggested that sperm qu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.289348
更新日期:2019-01-01 00:00:00
abstract::We describe a new liquid-chromatographic method with fluorescence detection for direct simultaneous determination of four urinary sulfate conjugates of 17-oxosteroids (17OS), without use of solvolysis or enzymatic hydrolysis. The 17OS sulfates in urine samples are extracted with benzene as ion pairs in the presence of...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-05-01 00:00:00
abstract::In this new method for determining urinary protein, the reaction is complete within 10 min at 37 degrees C. This method is applicable to automated as well as manual measurements. Protein concentration and absorbance at 600 nm are linearly related throughout a wide range of concentrations, 10 to 16 000 mg/L. However, t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-08-01 00:00:00
abstract::The identification of nicotinamide-N1-oxide as a metabolite in the urine of a schizophrenic patient prompted a study of the relative metabolism of nicotinic acid and nicotinamide in mental patients and healthy volunteers. Metabolites quantified included N1-methyl-2-pyridone-5-carboxamide, N1-methyl-4-pyridone-3-carbox...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-11-01 00:00:00
abstract::We developed a fluorometric method for determining delta-aminolevulinic acid (ALA) in urine of lead workers. A high-performance liquid chromatograph (HPLC) equipped with a fluorescence HPLC monitor is used. The detection limit for aqueous ALA is 20 micrograms/L (15 pmol of ALA in the 100-microL sample). The working li...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-09-01 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:BACKGROUND:The resurgence of the parasitic disease schistosomiasis calls for more efficient diagnostic tests. We developed a rapid, simple, portable, and sensitive immunoagglutination assay that uses SiO(2) particles and quartz crystal microbalance (QCM) for quantifying Schistosoma japonicum (Sj) antibodies (SjAb). ME...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.071555
更新日期:2006-11-01 00:00:00
abstract::We investigated the effects on plasma osteocalcin concentrations of different anticoagulants used to collect the blood samples. Plasma osteocalcin concentrations measured by enzyme immunoassay and radioimmunoassay are influenced by the nature of the anticoagulants used. The most significant difference between concentr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-02-01 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 compared a selection of quantitative immunological methods for prostatic acid phosphatase (PAP) with routine colorimetric assays for total and tartrate-labile acid phosphatase and evaluated their relative clinical merits in the differential diagnosis of prostatic carcinoma. We also assessed a wide range of commerci...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00