Abstract:
:Zinc protoporphyrin is the predominent fluorescent porphyrin accumulating in erythrocytes as a result of chronic lead absorption or iron-deficiency anemia. Although diagnostic concentrations or thresholds for it in erythrocytes have been inferred, normal adult averages have not been established. We quantitatively assessed average zinc protoporphyrin values during an investigation into the usefulness of magnetic circular dichroism spectroscopy as an analytical technique for biologic monitoring of industrial toxicant exposures. Blood samples drawn from 55 employees not exposed to lead were analyzed for blood lead, hematocrit, and zinc protoporphyrin. Average concentrations of zinc protoporphyrin determined with a hematofluorometer were compared with results obtained by magnetic circular dichroism spectroscopy. The latter results were comparable in kind but superior in quality to those of fluorometry. The magnetized spectroscopy followed Beer's Law at concentrations well below indigenous concentrations and was more sensitive than difference spectroscopy. Spectroscopic resolution of heme and zinc protoporphyrin moieties in a pyridine/NaOH mixture was complete.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Zygowicz ER,Hollebone BR,Perkins HMsubject
Has Abstractpub_date
1980-09-01 00:00:00pages
1413-8issue
10eissn
0009-9147issn
1530-8561journal_volume
26pub_type
杂志文章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::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...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-10-01 00:00:00
abstract:BACKGROUND:Recent use of Bacillus anthracis spores as a bioweapon has highlighted the need for a continuous monitoring system. Current monitoring systems rely on antibody-derived probes, which are not hardy enough to withstand long-term use under extreme conditions. We describe new, phage-derived probes that can be use...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2004.038018
更新日期:2004-10-01 00:00:00
abstract::Methods for measuring thyroid autoantibodies--to thyroperoxidase (TPOAb), thyroglobulin (TgAb), and thyrotropin receptor (TRAb)--have improved over the last decade, but increasingly, accurate and sensitive methods are needed for identifying patients with autoimmune thyroid diseases and individuals at high risk for ons...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1996-01-01 00:00:00
abstract::Serum folate, pteroylglutamic acid standards, and N-5-methyltetrahydrofolate standards extract differently during sample preparation for radiometric assay. B/B0 values for each material were determined before and after an alkaline extraction procedure. Serum folate most closely resembled N-5-methyltetrahydrofolate sta...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-04-01 00:00:00
abstract::We used a previously reported agarose-gel electrophoresis system to study the lipoprotein patterns in patients with type 3 hyperlipoproteinemia. All samples from 20 subjects tested revealed the presence of two bands with beta-lipoprotein mobility, irrespective of quantitative changes in plasma lipids induced by diet o...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-06-01 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::Imferon (Merrell-National), an iron-dextran complex, is widely used in patients with iron deficiency. It is present in the circulation in appreciable amounts for two to three weeks after administration and interferes with all tested colorimetric iron assays, both with and without deproteinization. The amount of the pl...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-04-01 00:00:00
abstract::To assess the distribution of serum concentrations of the atherogenic lipoprotein(a) [Lp(a)] in an obese population and the possible effects of weight reduction, we determined Lp(a) in 52 white, moderately obese subjects (16 men and 36 women). The subjects were participating in a weight-reduction program of diet, exer...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1991-07-01 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::We describe a completely automated enzymic system for measuring total cholesterol in serum. All reagents are contained in an analytical test pack and the test is performed on Du Pont's Automatic Clinical Analyzer (aca), which mixes the sample (20 microliter) and reagents and performs the necessary absorbance measureme...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-01-01 00:00:00
abstract:BACKGROUND:Although lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels are associated with cardiovascular events, Lp-PLA(2) is physically linked to LDL cholesterol (LDL-C). Whether measures of Lp-PLA(2) mass or activity continue to predict risk after LDL-C reduction by statin therapy is uncertain. METHODS:Lp...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2011.180281
更新日期:2012-05-01 00:00:00
abstract::We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile aci...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-02-01 00:00:00
abstract:BACKGROUND:Gradient gel electrophoresis (GGE) and nuclear magnetic resonance (NMR) spectroscopy are both widely accepted methods for measuring LDL and HDL particle size. However, whether or not GGE- or NMR-measured LDL or HDL particle size predicts coronary heart disease (CHD) risk to a similar extent is currently unkn...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.140939
更新日期:2010-05-01 00:00:00
abstract::We have studied factors affecting biological variation in total plasma alkaline phosphatase in a population of 32 329 apparently healthy subjects four years old or older. Quantification of the bone and liver isoenzymes after thermal denaturation made it possible to specify the contributions of each isoenzyme to variat...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-04-01 00:00:00
abstract::We describe a sensitive radioimmunoassay for rapidly determining the concentration of thyroxine in 10 microL of human serum. Aggregated antithyroxine antibodies are used to separate bound and free hormone. This speeds the assay and economizes on reagents without loss of sensitivity, specificity, or precision. Results ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-03-01 00:00:00
abstract:BACKGROUND:ADB-PINACA and its 5-fluoropentyl analog 5F-ADB-PINACA are among the most potent synthetic cannabinoids tested to date, with several severe intoxication cases. ADB-PINACA and 5F-ADB-PINACA have a different legal status, depending on the country. Synthetic cannabinoid metabolites predominate in urine, making ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.267575
更新日期:2017-05-01 00:00:00
abstract::We report the measure of prostate-specific antigen (PSA) from extracts of blood dried on filter paper. Five 3-mm (diameter) paper discs containing approximately 25 microL of dried whole blood were punched from the filter paper and extracted with 500 microL of buffer. Recovery of PSA was > 92%. Imprecision of the filte...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-04-01 00:00:00
abstract::Glucose was measured by the ferricyanide, the Beckman glucose oxidase, and the hexokinase procedures in 228 plasma samples taken during standard oral glucose-tolerance tests in 17 normal subjects and in 21 chemical diabetics. The neocuproine method was also used to measure glucose concentration in 156 samples (78 befo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-12-01 00:00:00
abstract::Risk can lead to catastrophe. Risk-management systems are highly effective in preventing the catastrophes of fire, earthquakes, and work-site injuries. No such effective systems are present to prevent health and social problems. A practical, cost-effective system to manage risk in children is being developed by the no...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00
abstract:BACKGROUND:Several plasma proteins have been suggested as markers for a variety of cardiovascular conditions but fail to qualify in independent patient cohorts. This may relate to interference of medication on plasma protein concentrations. We used proteomics to identify plasma proteins that changed in concentration wi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2017.282665
更新日期:2018-10-01 00:00:00
abstract::During direct illumination of a serum bilirubin solution the bilirubin concentration decreased markedly, both as determined by the direct spectrometric method and (even more so) by the diazo method. In contrast, I found the same values for serum bilirubin concentrations as determined by these two methods for serum fro...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-01-01 00:00:00
abstract::This two-site immunoradiometric assay for human parathyrin-related protein 1-86 (PTHRP1-86) in plasma uses a mouse monoclonal antibody to PTHRP1-34 coupled to cellulose particles for immunoextraction of N-terminal immunoreactivity, and a rabbit antiserum to PTHRP37-67 that is indirectly labeled with 125I-labeled PTHRP...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1991-05-01 00:00:00
abstract::A quantitative "high-performance" liquid-chromatographic method is described for determining porphyrins in human urine. Porphyrinogens in urine are first converted to the corresponding porphyrins by oxidation with iodine. Uroporphyrin, hepatacarboxylic acid porphyrin, hexacarboxylic acid porphyrin, pentacarboxylic aci...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1989-08-01 00:00:00
abstract:BACKGROUND:Altered germline expression of genes may represent a powerful marker of genetic or epigenetic predisposition to cancer or other diseases. METHODS:We developed and validated a method of nonfluorescent primer extension that uses a single dideoxynucleotide and denaturing HPLC (DHPLC) to analyze the relative al...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.126300
更新日期:2009-09-01 00:00:00
abstract:BACKGROUND:Heparinized plasma samples allow more rapid analysis than serum samples, but preliminary studies showed lower cardiac troponin T (cTnT) results in plasma. We undertook a multicenter study to characterize this effect for cTnT and cardiac troponin I (cTnI). METHODS:Blood samples were collected with and withou...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章,多中心研究
doi:
更新日期:2000-06-01 00:00:00
abstract:BACKGROUND:KLK5 is a newly discovered human kallikrein gene. Many kallikrein genes have been found to be differentially expressed in various malignancies, and prostate-specific antigen (PSA; encoded by the KLK3 gene) is the best tumor marker for prostate cancer. Like the genes that encode PSA and other kallikreins, the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-08-01 00:00:00
abstract::We have compared the operational, medical, and fiscal consequences of performing urgent glucose testing at the bedside vs in the central laboratory. The turnaround time (TAT) with bedside testing was only 1-2 min shorter than that from the central laboratory, to which specimens are sent by pneumatic tube and from whic...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-08-01 00:00:00
abstract::A monoclonal-antibody-based competitive radioimmunoassay for measuring human protein C is reported. With use of a purified protein C standard, the solid-phase assay was sensitive to less than 80 micrograms of protein C per liter. Intraassay CVs ranged from 5% to 8%; the inter-assay CV was 5.4%. Analytical recovery ave...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-02-01 00:00:00
abstract:BACKGROUND:The genotype of hepatitis C virus (HCV) is a predictor of antiviral therapeutic response. We describe an approach for HCV genotype determination by real-time PCR and melting curve analysis. METHODS:After automated nucleic acid extraction, we used reverse transcription-PCR in a block cycler to amplify nucleo...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:2002-12-01 00:00:00