Abstract：
:We find lag phases exceeding 20 min in measuring creatine kinase activity, by using the kinetic creatin phosphate leads to creatine assay, in sera of some patients with carcinoma metastatic to the liver. Such long lag phases are accompanied by a decreased apparent enzyme activity. These problems are eliminated by adding sulfhydryl agents to the serum before assay, but not by adding more of such agents to the assay reagent. beta-Mercaptoethanol is supperior to Cleland's reagents, glutathione, and cysteine. The long lag phases could not be explained by inadequate activity of the coupling enzymes, interference with the coupling steps, high proportions of cardiacisoenzymes activity, simple oxidation of the enzyme, low concentrations of albumin, or increased concentrations of glutathione reductase, lactate dehydrogenase, or uric acid. We conclude that the prolonged lag phases reflect inadequate reactivation of the enzyme by sulfhydryl agents under the usual assay conditions. Reactivation before assay can prevent potentially serious negative errors in the assay of creatine kinase.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Bruns DE,Morgan WS,Davis JE,Ladenson JHsubject
Has Abstractpub_date
1976-11-01 00:00:00pages
1889-95issue
11eissn
0009-9147issn
1530-8561journal_volume
22pub_type
杂志文章abstract：:We describe a system for detection of leukemia cells involving complement-mediated cytotoxic reaction and an image processing system, consisting of a charge-coupled-device image sensor, an image memory board, a personal computer, and a phase-contrast microscope. Then added to a cell suspension, monoclonal antibody spe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-04-01 00:00:00
abstract：:We evaluated the density-gradient ultracentrifugation method in a swinging-bucket rotor (Anal Biochem 111, 149-157, 1981) in a slightly modified version for isolation and determination of high-density lipoprotein (HDL) subfractions. We prestained the serum with Coomassie Brilliant Blue R, which did not change the hydr...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-04-01 00:00:00
abstract：BACKGROUND:The diagnosis of 22q11 deletion syndrome (22q11DS) is often delayed or missed due to the wide spectrum of clinical involvement ranging from mild to severe, often life-threatening conditions. A delayed diagnosis can lead to life-long health issues that could be ameliorated with early intervention and treatmen...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2014.230086
更新日期：2015-01-01 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：:We describe an automated determination of serum hexosamine by the Elson-Morgan reaction, together with reagent modifications that minimiz interference from amino acids and sugars present in acid hydrolysates of sera. We used a novel 15-min autoclave procedure for the acid hydrolysis of sera before analysis to facilita...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-08-01 00:00:00
abstract：:This ultrafiltration technique allows determination of free drug in 50 microL of serum. We ultrafiltered sera containing the following drugs--valproic acid (and its major metabolites), phenobarbital, diazepam, indomethacin, phenytoin, furosemide, and chloramphenicol--using both the commercially available micropartitio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-06-01 00:00:00
abstract：:We describe a "high-performance" liquid-chromatographic assay for measuring ritalinic acid in 300 muL of serum. The procedure includes adsorption of ritalinic acid and internal standard (alpha,alpha-dimethyl-beta-emthylsuccinimide) from serum onto charcoal, from which both compounds are eluted with methanol. The metha...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-01-01 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：:I describe an assay for serum estriol during pregnancy, which does not require prior extraction or chromatography of the serum. Fifty microliters of 20-fold diluted serum can be assayed to detect as little as 20 pg of estriol. For a 20 mug/liter serum estriol concentration the CV was 16%; for 100 mug/liter concentrati...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-04-01 00:00:00
abstract：BACKGROUND:An association has been described between mortality in children with meningococcal disease and functional polymorphisms in the interleukin-1 (IL1) cluster. We undertook a multicenter study to evaluate associations of these polymorphisms in a Central European population. PATIENTS AND METHODS:The study involv...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2005.058537
更新日期：2006-03-01 00:00:00
abstract：:The difference in absorbance (delta A) between equimolar acid and alkaline solutions of methyl red, at a wavelength near the isosbestic point of the indicator, is reproducible. Furthermore, this delta A is sensitive to changes in the wavelength calibration of the instrument used to make the measurement. The delta A of...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：:Histograms of the results of quantitative clinical laboratory analyses are usually broadly skewed because some of the patients have normal values with respect to the analyte being measured while values for others are below or above normal. We describe a technique for calculating the maximum possible number of individu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-04-01 00:00:00
abstract：:To evaluate their potential usefulness in the differential diagnosis of Cushing's syndrome, we estimated the urinary excretion rates of the following non-metabolized, unbound steroid hormones: pregnenolone, progesterone, 17-OH-pregnenolone, 17-OH-progesterone, dehydroepiandrosterone (DHEA), androstenedione, testostero...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：BACKGROUND:We previously reported a family in which the propositus and both her father and paternal grandmother had high serum aminopeptidase N (CD13; EC 3.4.11.2) activity (autosomal dominant). The molecular mass of the serum CD13 polypeptide of the propositus was larger than that of normal CD13, suggesting either a m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-02-01 00:00:00
abstract：:A reaction of urea, o-phthalaldehyde and N-(1-naphthyl)ethylenediamine is described for measurement of urea by manual, continuous-flow, and kinetic methods. The continuous-flow system requires 25 mu-l of sample; 40 samples can be analyzed per hour. The kinetic method requires no enzymes, has no lag phase, and has good...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-07-01 00:00:00
abstract：:In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable conc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-09-01 00:00:00
abstract：BACKGROUND:To allow multianalyte binding assays, we have developed a novel polystyrene microtiter plate containing 24 main wells, each divided into 7 subwells. We explored its clinical potential by developing a PCR-chemiluminescent immunoassay (PCR-CLEIA) for simultaneous detection and typing of seven high oncogenic ri...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：2002-10-01 00:00:00
abstract：:We present an improved Na+-selective liquid membrane electrode for measurement of Na+ concentrations in both undiluted serum and urine. The values for urinary Na+ obtained with the ion-selective electrode agree well with those obtained with the flame photometer. The correlation gives a standard residual deviation of +...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-08-01 00:00:00
abstract：:We describe an improved procedure for the preparation of plasma or serum for determination of theophylline by reverse phase high-performance liquid chromatography. Quantitative results are available in less than 30 min from receipt of sample. The chromatogram is complete in 8 to 16 min, which includes the use of an in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:A simple, precise, and rapid method to measure plasma malondialdehyde (MDA) was developed by use of solvent extraction--flow-injection analysis. The reagent solution, containing thiobarbituric acid (TBA), 5 g/L in 100 mL/L phosphoric acid, and extraction solvent (methylisobutyl ketone, MIBK) were propelled with a doub...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-10-01 00:00:00
abstract：BACKGROUND:The analysis of bodily fluids using SELDI-TOF MS has been reported to identify signatures of spectral peaks that can be used to differentiate patients with a specific disease from normal or control patients. This report is the 2nd of 2 companion articles describing a validation study of a SELDI-TOF MS approa...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2007.091496
更新日期：2008-01-01 00:00:00
abstract：:Quinidine in serum was measured at 330 nm, after protein precipitation, with an alkyl phenyl reversed-phase chromatographic column by peak-height determination (external standards.) Sensitivity was 0.3 mg/liter, with linear response to at least 10 mg/liter serum. Interassay precision, measured on 20 consecutive days, ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
abstract：:We developed a radioimmunoassay with a gamma-emitting radioligand to measure androstenedione in human serum and in dried blood-spot samples from newborns. Antisera were raised in rabbits against androstenedione linked to bovine serum albumin at positions 3, 6, or 11 on the steroid nucleus. Radioligands were prepared b...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
abstract：:We report the results of a laboratory and clinical evaluation of a commercial kit procedure (Immuno Nuclear Corp.) for measuring the mid-region of the parathyrin molecule. The estimated dose at 50% binding averaged 130 pmol/L, and the minimum detectable concentration was 14 pmol/L. The within-assay CV was less than or...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-11-01 00:00:00
abstract：:Four double-monoclonal time-resolved immunofluorometric assays (TrIFMAs) have been developed for the specific determination of pregnancy-associated plasma protein A/proeosinophil major basic protein (PAPP-A/ proMBP) complex in first-trimester maternal serum samples. The assays have a functional sensitivity of < 4 mIU/...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：BACKGROUND:Hypoxic ischemic encephalopathy (HIE) is a major cause of permanent neurological disabilities in full-term newborns. We measured activin A in urine collected immediately after birth in asphyxiated full-term newborns, and assessed the ability of the measurements to predict the occurrence of perinatal encephal...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.062604
更新日期：2007-03-01 00:00:00
abstract：:The ultraviolet fluorescence emission spectra of sera from apparently healthy persons and of sera from cancer patients frequently show significantly different curve shapes. A biparametric fluorescence method has been developed to use these deviations to detect patients with malignant diseases (Clin Chem 1986;32:1974-8...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-11-01 00:00:00
abstract：:A simple and convenient method using commercially available derivatization reagents is described for the measurement of betaine and N,N-dimethylglycine (DMG) in blood and urine. Precolumn derivatization of plasma or urine is performed directly in acetonitrile without extraction with p-bromophenacyl bromide and crown e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:We describe a novel radioimmunoassay procedure for the direct estimation of aldosterone in unextracted plasma and serum samples, in which interfering binding proteins are digested by Proteinase K (Tritirachium alkaline proteinase, EC 3.4.21.14), a powerful proteolytic enzyme. Heating at 75 degrees C for 15 min inactiv...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-12-01 00:00:00
abstract：:Serum free thyroxin (FT4) was determined in 40 patients with various nonthyroidal illnesses. We studied seven methods: (1) a free thyroxin index calculated from total T4 and triiodothyronine resin uptake; (2) a free T4 index determined by enzyme inhibitor assays (Abbott's "Tetrazyme" and "Thyrozyme"); (3) a free T4 in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
