Abstract：
:The reaction of 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB, Ellman's reagent) with thiols is sensitive to daylight, in particular to ultraviolet radiation at wavelengths around 325 nm. Exposure to light at the absorbance maximum of the yellow product (the thionitrobenzoate ion) at 410 nm had no effect on the reaction. The light-sensitive species is apparently the DTNB, because a spectral-irradiation experiment showed that the wavelength of light that produced the maximum rate of absorbance change coincided with the peak absorbance of DTNB, and it was well separated from the thionitrobenzoate absorbance peak. Ascorbate is ineffective as a stabilizer and can produce an apparent increase in the rate of DTNB destruction. In a practical example we found the light interference to be severe when hydrolysis of propionylthiocholine by plasma cholinesterase (EC 3.1.1.8) was measured after a 20-min incubation. The apparent cholinesterase activity in clear glass or plastic tubes exposed to diffuse daylight could be decreased to 25% of the value obtained for samples in light-excluded tubes. We recommend the reaction be carried out in artificial room light, with total elimination of daylight, because window glass does not sufficiently attenuate 325-nm wavelength irradiation.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Walmsley TA,Abernethy MH,Fitzgerald HPsubject
Has Abstractpub_date
1987-10-01 00:00:00pages
1928-31issue
10eissn
0009-9147issn
1530-8561journal_volume
33pub_type
杂志文章abstract：BACKGROUND:Quantification of integrated proviral HIV DNA by repetitive-sampling Alu-HIV PCR is a candidate virological tool to monitor the HIV reservoir in patients. However, the experimental procedures and data analysis of the assay are complex and hinder its widespread use. Here, we provide an improved and simplified...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.219378
更新日期：2014-06-01 00:00:00
abstract：BACKGROUND:Little is known about lipoprotein(a) [Lp(a)] as a predictor of vascular events among ethnic Chinese. We prospectively investigated the association of Lp(a) with cardiovascular disease and all-cause death in a community-based cohort. METHODS:We conducted a community-based prospective cohort study of 3484 par...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.090969
更新日期：2008-02-01 00:00:00
abstract：BACKGROUND:Lysosomal storage disorders (LSDs) comprise more than 40 genetic diseases that result in the accumulation of products that would normally be degraded by lysosomal enzymes. A tandem mass spectrometry (MS/MS)-based method is available for newborn screening for 5 LSDs, and many laboratories are initiating pilot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.111864
更新日期：2009-01-01 00:00:00
abstract：BACKGROUND:A genomic deletion of exon 3 (d3-GHR) of the growth hormone (GH) receptor (GHR) has been linked to the effectiveness of GH therapy in children with GH deficiency. Carriers of the d3-GHR genotype had higher GH-induced growth rates than children homozygous for the full-length (fl)-GHR. The aim of this study wa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.085712
更新日期：2007-08-01 00:00:00
abstract：:We measured the free amino acids in plasma of 58 patients with HIV infection and in six persons in the risk group. The HIV+ patients had significantly increased concentrations of arginine, phenylalanine, and glutamate in comparison with both age- and sex-matched controls and the members of the risk group. Glutamate co...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-09-01 00:00:00
abstract：:We assessed the LKB "Delfia" (time-resolved dissociation-enhanced lanthanide fluoroimmunoassay) and the Amersham "Amerlite" (enhanced luminescent immunometry) assays of thyrotropin in serum. Both assays are sensitive (respective detection limits: 0.02 and 0.04 milli-int. unit/L) and have very good within- and between-...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
abstract：:We have assessed the technical performance and robustness of NycoCard CRP Whole Blood, a near-patient test for C-reactive protein (CRP), when used in realistic daily routine situations in general practice clinics (GPC). Thirteen GPCs participated, five of them with technician staff. From 898 patients, split-sample mea...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-11-01 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：BACKGROUND:We describe a simple tetra-primer amplification refractory mutation system PCR (T-ARMS-PCR) for detecting MUTYH mutations, which are associated with colorectal adenomas and colorectal cancer. METHODS:We designed specific T-ARMS-PCR assays for 6 mutations (Y165C, G382D, 1395_7delGGA, Y90X, 1103delC, and R231...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.060137
更新日期：2006-04-01 00:00:00
abstract：BACKGROUND:About 5% of patients with neurofibromatosis type 1 (NF1) bear constitutional microdeletions that encompass NF1 (neurofibromin 1) and neighboring genes. These patients are characterized by the development of a high number of dermal neurofibromas (dNFs), mental retardation, and an increased risk of developing ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2012.194217
更新日期：2013-06-01 00:00:00
abstract：:The technology needed to genetically engineer antibodies is evolving rapidly and the potential utility of these novel reagents is being explored with vigor. The process includes cloning of the antibody genes, their in vitro manipulation and mutagenesis, expression in a suitable host/vector system, and, for commercial ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1989-09-01 00:00:00
abstract：:Radioimmunoassay of triiodothyronine was performed with a homogeneous incubation system. Bound and free ligand were separated by partitioning in an aqueous two-phase system. The agreement between the results obtained with this technique and conventional heterogeneous radioimmunoassay was very good (r = 0.981). ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：BACKGROUND:Plasma B-type cardiac natriuretic peptides reflect cardiac structure and function and have proven roles in assisting in the diagnosis of acute heart failure. They are independent prognostic indicators across the full spectrum of cardiovascular disease. Serial changes in plasma B-type cardiac natriuretic pept...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2011.165704
更新日期：2012-01-01 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：:Sensitive and specific radioimmunoassays of metanephrine and normetanephrine were developed by use of 125I-labeled synephrine and specific metanephrine antibody, and 125I-labeled octopamine and specific normetanephrine antibody. Specific antibody for both metanephrine and normetanephrine was raised in rabbits by immun...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-10-01 00:00:00
abstract：:We have devloped an enzyme-linked immunosorbent assay for determining choriomammotropin (human placental lactogen) in serum. Unlabeled hormone competes with choriomammotropin-beta-galactosidase conjugate for antibody bound to polystyrene tubes. The entire assay can be performed in 2.5 h with good precision. The coeffi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-02-01 00:00:00
abstract：BACKGROUND:Patients with trophoblastic diseases produce ordinary and irregular forms of human chorionic gonadotropin (hCG; e.g., nicked hCG, hCG missing the beta-subunit C-terminal segment, hyperglycosylated hCG, and free beta subunit) that are recognized to differing extents by automated immunometric hCG (or hCG beta)...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-02-01 00:00:00
abstract：BACKGROUND:We evaluated kinetic changes of high-sensitivity cardiac troponin T (hs-cTnT) in patients with acute coronary syndrome (ACS) and patients with hs-cTnT increases not due to ACS to rule in or rule out non-ST-segment elevation myocardial infarction (STEMI). METHODS:hs-cTnT was measured serially in consecutive ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.171827
更新日期：2012-01-01 00:00:00
abstract：BACKGROUND:False-positive results are a common problem in real-time PCR identification of DNA sequences that differ from near neighbors by a single-nucleotide polymorphism (SNP) or deletion. Because of a lack of sufficient probe specificity, post-PCR analysis, such as a melting curve, is often required for mutation dif...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.091488
更新日期：2007-12-01 00:00:00
abstract：BACKGROUND:Immunoassays specific for 1-84 parathyroid hormone (PTH) reportedly reflect the bioactivity of PTH; however, PTH immunoassays can be susceptible to interference by cross-reacting PTH fragments. In addition, these assays currently lack standardization. A methodology using immunocapture purification with liqui...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.134643
更新日期：2010-02-01 00:00:00
abstract：BACKGROUND:Measurement of hemoglobin A1c (HbA1c) in the blood is integral to and essential for the treatment of patients with diabetes mellitus. HbA1c reflects the mean blood glucose concentration over the preceding 8 to 12 weeks. Although the clinical value of HbA1c was initially limited by large differences in result...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2018.296962
更新日期：2019-07-01 00:00:00
abstract：BACKGROUND:Quantitative, miniaturized nucleic acid assays and immunoassays can be developed with single microparticles, microfluorometric detection, and intrinsically fluorescent lanthanide chelates in a multiple assay format to decrease reagent consumption, cost, and assay time. We used recombinant Fab fragments to ca...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-11-01 00:00:00
abstract：:With use of a specially designed gradient-generating system, of anion-exchange resins of 10-20 mum particle diameter, and of an orcinol solution in concentrated sulfuric acid (1 g/liter) as detection reagent, a mixture of 16 carbohydrates can be separated in less than 4 h. The limit of detection for most sugars is in ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-12-01 00:00:00
abstract：BACKGROUND:The determination of cellular beta-galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell-based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for beta-ga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.115873
更新日期：2009-03-01 00:00:00
abstract：:Estimation of plasma catecholamine concentrations by "high-performance" liquid chromatography, although increasingly used, still presents difficulties. We describe a method for clean-up of plasma samples on cation-exchange resin before they are extracted with alumina. This procedure eliminates many of the interfering ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-07-01 00:00:00
abstract：BACKGROUND:5α-Reductase 2 deficiency (5ARD) is a known cause of 46,XY disorders of sex development (DSD). Traditionally, the diagnosis relies on dihydrotestosterone (DHT) measurement, but the results are often equivocal, potentially leading to misdiagnosis. We reviewed alternative approaches for diagnosis of 5ARD. MET...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2012.196501
更新日期：2013-05-01 00:00:00
abstract：:In this rapid, simple enzyme immunoassay for carcinoembryonic antigen (CEA) in serum the "sandwich" system is used. The CEA is first extracted from the serum into acetate buffer by heating at 70 degrees C, then incubated in a polyvinyl microtitration plate previously coated with anti-CEA. The bound CEA is then reacted...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
abstract：:We describe a gas chromatographic method for measuring submicrogram quantities of dianhydrogalactitol, a promising antineoplastic agent (currently undergoing clinical trials in humans), in plasma. The drug is first extracted from blood plasma by saturating the aqueous phase with solid potassium carbonate and extractin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-10-01 00:00:00
abstract：:We measured changes in concentrations of magnesium, zinc, calcium, potassium, cholesterol [total and high-density lipoproteins (HDL)], total creatine kinase (CK), and CK isoenzyme-MB in plasma (PI) and/or erythrocytes (Erc) from apparently healthy subjects and from patients with either pre-infarction syndrome (PIS) or...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-10-01 00:00:00
abstract：:An optimized assay for alkaline phosphatase (EC 3.1.3.1) is reported. A discrete analyzer, the DuPont Automatic Clinical Analyzer (aca), was used for this study. The assay is based on results of response-surface experimental co-optimization techniques, and response is enhanced over the present aca assay. A key feature...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-07-01 00:00:00
