Abstract：
:Creatinine and specific gravity (relative density) measurements both allow differences in urine concentration to be taken into account in determining urine cotinine concentrations. In this study we demonstrate that the variance of urine cotinine measurements is reduced comparably when either creatinine or specific gravity measurements are used for correction. This reduction in variability improves the correlation between urine cotinine measurements and clinical endpoints. In this study, the clinical endpoints were pulmonary function in a population of nonsmoking children with asthma, 42% of whom were reported to have been exposed to environmental tobacco smoke. When corrected by either creatinine measurements or specific gravity values, the urine cotinine measurements performed as well or better than reported exposure (and comparably with each other) in assessments of lung function. A dose-response relationship was also more consistently apparent. Specific gravity values can be used reliably in place of creatinine values to adjust urine cotinine measurements for both research and clinical purposes.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Haddow JE,Knight GJ,Palomaki GE,Neveux LM,Chilmonczyk BAsubject
Has Abstractpub_date
1994-04-01 00:00:00pages
562-4issue
4eissn
0009-9147issn
1530-8561journal_volume
40pub_type
杂志文章abstract：BACKGROUND:Little is known about trace metal alterations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentrations of trace elements. Because these patients are at risk for alterations of trace elements as well as for ...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：
更新日期：1999-09-01 00:00:00
abstract：:We investigated the ability of neural networks to diagnose acute myocardial infarction (AMI) from laboratory data only. Several networks were trained with different combinations of data obtained at admission and within the first 12 h and 24 h after admission. The data used included the electrocardiogram (ECG) and the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-04-01 00:00:00
abstract：:In "flow-injection analysis," the sample is inserted into a stream of reagent by use of a sample-injection valve. Mixing occurs downstream from the valve in a coil of tubing. With chemiluminescence detection this coil is positioned in front of a photomultiplier. We have evaluated the system for detection of hydrogen p...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-09-01 00:00:00
abstract：:We describe a radioassay for cobalamin (vitamin B12) in human serum or plasma that requires no boiling or other pretreatment of the sample. Normal chicken serum covalently coupled to magnetizable particles is used as the binding agent. The assay is performed at pH 12.9, at which pH all cobalamin in human serum is rele...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-02-01 00:00:00
abstract：BACKGROUND:In the workup of patients with suspected hereditary nonpolyposis colorectal cancer (HNPCC), detection of loss of heterozygosity (LOH) could help pinpoint the mismatch-repair (MMR) gene carrying the germline mutation, but analysis of microsatellite markers has proved unreliable for this purpose. We developed ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.108902
更新日期：2008-11-01 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：:In this enzyme-linked immunoassay for human thyrotropin (TSH) in unextracted serum we use 96-well immunoenzymometric assay plates, first coated with polyclonal antibody to TSH, then incubated with the serum samples and reacted with mouse monoclonal antibody to human TSH. After incubation with alkaline phosphatase-labe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-07-01 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：:To clarify whether manganese nutritional status is better reflected by the manganese concentration in lymphocytes or in whole blood, we injected manganese solutions intravenously into manganese-deficient rats and determined manganese concentrations in lymphocytes, whole blood, and various tissues. The manganese concen...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
abstract：:Agarose column chromatography has been used to separate plasma lipoproteins into very-low-density lipoproteins (VLDL), low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Applied to the diagnosis of primary type III hyperlipoproteinemia, the procedure is capable of demonstrating three characteristic an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-12-01 00:00:00
abstract：:Several aspects of mass spectrometry and gas chromatography-mass spectrometry are reviewed, including ionization methods, repetitive scanning, selected ion monitoring, and stable isotope measurement. I discuss the application of these and other mass spectrometry methods to the investigation of compound classes relevan...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-06-01 00:00:00
abstract：BACKGROUND:Absolute plasma hepcidin concentrations measured by various procedures differ substantially, complicating interpretation of results and rendering reference intervals method dependent. We investigated the degree of equivalence achievable by harmonization and the identification of a commutable secondary refere...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.256768
更新日期：2016-07-01 00:00:00
abstract：:In this method for separating glycosylated from nonglycosylated hemoglobin in blood by electrophoresis on cellulose acetate membranes, we exploit the affinity of low-molecular-mass dextran sulfate for the nonglycosylated fraction, which increases the mobility of the latter relative to that of glycosylated hemoglobin. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-02-01 00:00:00
abstract：:A dissociation-enhanced lanthanide fluoroimmunoassay of serum cortisol based on time-resolved fluorescence is described. The assay is a direct assay, where cortisol immobilized on the wall of a microtiter-strip well competes with cortisol in the sample for the europium-labeled polyclonal antibody. The amount of bound ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-10-01 00:00:00
abstract：:Both cellulose acetate electrophoresis and citrate agar electrophoresis were performed on 834 blood samples collected on filter paper in Jamaica and shipped for testing to the National Hemoglobinopathy Standardization Laboratory at the U.S. National Center for Disease Control. Additionally, 30 blood samples collected ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-05-01 00:00:00
abstract：:We determined approximately 15,000 laboratory values in 236 individuals between the ages of 60 and 90 y, 22 individuals between 90 and 99 y, and 69 individuals greater than or equal to 100 y, and compared these with values in young adults. We tested 47 different analytes in the 60-90-y group and 93 analytes in the gre...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-06-01 00:00:00
abstract：BACKGROUND:Although minimum regulatory standards exist for determining QC testing frequency, decisions regarding when and how to run QC samples are not standardized. Most QC testing strategies test control samples at fixed time intervals, often placing the samples in the same position on an instrument during subsequent...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.083311
更新日期：2007-04-01 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：:We studied the effects of some chelators on creatine kinase activity. Creatine kinase is competitively inhibited by endogenous polyvalent cations (e.g., calcium, Ki = 4.5 mmol/L); this can be reversed by adding chelators to the reagent, resulting in a mean increase in activity of 1.14-fold at 25 degrees C and 1.18-fol...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-03-01 00:00:00
abstract：:A modified heparin-Sepharose affinity chromatography procedure (Boberg et al., J. Lipid Res. 18:544-547, 1977) was developed to determine two different triglyceride lipase activities in human post-heparin plasma: hepatic triglyceride lipase (I) and lipoprotein lipase (II). With this procedure, lipoproteins were separa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-05-01 00:00:00
abstract：:We combined the amplification refractory mutation system (ARMS) and fluorescence polarization (FP) to give a homogeneous genomic DNA genotype analysis method. Oligonucleotide probes labeled with the fluorescein dyes fluorescein isothiocyanate and 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein and the rhodamine dye 6-c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-08-01 00:00:00
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 act...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-05-01 00:00:00
abstract：:A total of 1357 polypeptides [946 acidic (isoelectric focusing) and 411 basic (nonequilibrium pH-gradient electrophoresis)] from human HeLa cells have been separated and catalogued with use of high-resolution two-dimensional gel electrophoresis. Of these polypeptides, 1266 were detected by labeling cells with [35S]met...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：:Seeking to minimize degradation of NADPH during storage, reagent preparation, and assays, we investigated the effects of pH, temperature, and ionic strength as well as the effects of phosphate and acetate. NADH was also included for comparison. Our results indicate that the rate of degradation of NADPH is proportional...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-02-01 00:00:00
abstract：:We compared results obtained with a commercial immunoradiometric assay kit for human thyrotropin in which monoclonal antibodies are used (Tandem -R TSH (ONE STEP) ImmunoRadioMetricAssay; Hybritech Inc.) with those obtained with two commercial radioimmunoassay methods: GAMMA-DAB [125I]HS-hTSH RIA (Clinical Assays) and ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-06-01 00:00:00
abstract：BACKGROUND:Previous methods to measure glycohemoglobin (GHb) have been time-consuming or imprecise; we therefore developed a new enzymatic assay for GHb. METHODS:Blood cells were first hemolyzed, and hemoglobin was digested with protease to yield fructosyl amino acid. Fructosyl amino acid oxidase acts on the fructosyl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.2.269
更新日期：2003-02-01 00:00:00
abstract：:The isoenzyme pattern of N-acetyl-beta-glucosaminidase (NAG) in serum and urine was studied in two groups of patients with diabetes mellitus and in 30 control subjects. Total NAG activity was significantly (P less than 0.001) increased in the serum and urine of the 20 diabetics with vascular complications, but was ins...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
abstract：:Direct-injection analysis for phenylalanine in plasma by isocratic "high-performance" liquid chromatography (HPLC) is described. For chromatographic separation I use an internal-surface reversed-phase silica support. The method involves ultraviolet detection, requires as little as 10 microL of plasma (routinely 20 mic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-06-01 00:00:00
abstract：:We measured the rate of elimination of phenylalanine by constant intravenous infusion of L-phenylalanine in 14 parents of children with phenylketonuria and in 21 subjects with a negative family history for this disease. When reciprocals of the observed elimination rates were plotted against the reciprocals of the incr...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-09-01 00:00:00
abstract：:A new radiometric assay specific for creatine kinase isoenzyme MB was evaluated with respect to its precision and agreement with a conventional electrophoretic CK-MB assay for the diagnosis of myocardial infarction. The reference interval we find for serum CK-MB in healthy subjects is 0--30 micrograms/L. The coefficie...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-06-01 00:00:00
