Abstract:
:We examined the changes in sensitivity and specificity that would occur with alterations in the sample-collection schedule and (or) cutoff criterion for the increase in hydrogen concentration in breath after administration of doses of lactose in the dietary range. In a breath-analysis test to classify individuals as lactose-absorbers or lactose-malabsorbers, 41 subjects drank 360 mL of intact cow's milk, containing 18 g of lactose, and breath samples were collected and analyzed at 30-min intervals for 5 h. An increase in H2 concentration of greater than or equal to 20 microL/L above basal values at any of the 10 intervals was diagnostic of malabsorption. Increases of greater than or equal to 18 or greater than or equal to 15 microL/L were only 85% as specific in classifying the same individuals. Reduction in the number of samples tested per subject uniformly reduced the sensitivity. However, a simplified procedure suitable for field studies (in which four samples--at 0, 2, 3, and 4 h--are collected and analyzed with greater than or equal to 20 microL/L as the cutoff value) gives 80% sensitivity and 100% specificity, as compared with the 11-sample procedure.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Rosado JL,Solomons NWsubject
Has Abstractpub_date
1983-03-01 00:00:00pages
545-8issue
3eissn
0009-9147issn
1530-8561journal_volume
29pub_type
杂志文章abstract:BACKGROUND:Gas6 is a vitamin K-dependent antiapoptotic protein that has been implicated in cardiovascular pathophysiology. We report the development and validation of an ELISA for Gas6, and the variation of plasma Gas6 with hormonal status in a study designed to evaluate the effect of oral contraception on plasma marke...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.089102
更新日期:2007-10-01 00:00:00
abstract::We describe a simple, highly reproducible kinetic technique for precisely measuring temperature in spectrophotometric systems having reaction cells that are inaccessible to conventional temperature probes. The method is based on the temperature dependence of pseudo-first-order rate constants for the acid-catalyzed hyd...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-05-01 00:00:00
abstract::In this automated system for assaying guanidino compounds, the compounds are resolved on an ion-exchange (Dowex 50) column, then reacted with phenanthrenequinone in alkaline solution. This mixture is then acidified and the resulting fluorescence is measured (lambda ex, 305 nm; lambda em, 395 nm). I applied the system ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-02-01 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: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:BACKGROUND:There is need for a reference method for transferrin glycoforms in serum to which routine immunologic methods for the alcohol marker carbohydrate-deficient transferrin (CDT) can be traceable. We describe an improved HPLC method for transferrin glycoforms. METHODS:Transferrin was iron-saturated by mixing the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.023341
更新日期:2003-11-01 00:00:00
abstract:BACKGROUND:Laboratory tests can be an important source of blood loss in hospitals, especially for newborns and patients in intensive care. The aim of this study was to quantify blood loss for laboratory diagnostic tests in a large number of patients in a teaching hospital. METHODS:We estimated blood loss by multiplyin...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.10.1651
更新日期:2003-10-01 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 this simple, quick procedure for determining copper in human serum and urine, the serum and urine specimens were analyzed directly after dilution with a solution of HNO3 and Triton X-100, 1 mL/L each. We calibrated with aqueous standards for quantitation in Zeeman background atomic absorption spectrometry. By modif...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-09-01 00:00:00
abstract::We report the presence of complexes between aspartate aminotransferase (AST, EC 2.6.1.1) and immunoglobulin (Ig) in the serum of a patient suffering from lung cancer with metastasis to the liver. After fractionation of the serum by gel filtration, AST-Ig complexes (AST-IgA, AST-IgG) were demonstrated by counterimmunoe...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1983-02-01 00:00:00
abstract::Binary-system capillary electrophoresis (CE) with head-column field-amplified sample stacking permits determination of amiodarone and desethylamiodarone in 20-microL serum samples. The assay is characterized by a detection limit for both compounds of 80 nmol/L and by excellent linear response over the recommended ther...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1996-11-01 00:00:00
abstract::Radiometric, colorimetric, and two immunochemical methods for measuring total iron-binding capacity are compared. We evaluated the procedures on the basis of precision, applicability to a pediatric population, and accuracy as assessed by analytical recovery of purified transferrin. The immunoephelometric assay for tra...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-10-01 00:00:00
abstract::The immunoreactivity of anti-triiodothyronine (anti-T3) IgG, pretreated at acidic pH and adsorbed onto polystyrene beads, was significantly greater than that determined for native anti-T3 IgG immobilized at optimum pH 3.5. Acidic-pH-pretreated IgG, adsorbed at pH 7.0 onto ethanol-treated beads, had less immunoreactivi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-03-01 00:00:00
abstract::We have developed an interactive statistical quality-control system for the small- to medium-sized radioimmunoassay laboratory, which can be used in a programmable desk-top calculator instead of the medium- or large-scale computer systems usually required. The design of this quality-control system is modeled after the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-07-01 00:00:00
abstract:BACKGROUND:Associations between dairy intake and body composition and cardiometabolic traits have been inconsistently observed in epidemiological studies, and the causal relationship remains ill-defined. METHODS:We performed Mendelian randomization analysis using an established genetic variant located upstream of the ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.300335
更新日期:2019-06-01 00:00:00
abstract::Two-dimensional protein maps of biopsies from normal mucosa, tubular adenomas (polyps), and colonic carcinomas in humans have been studied in order to obtain information on the possible precancerous role of intestinal polyps. The maps are complex and several hundred protein spots are seen after staining with Coomassie...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-04-01 00:00:00
abstract::HbCO in blood sampled from 20 mothers and newborns immediately after birth was measured with a new, simple gas-chromatographic method for CO. The mean ratio of HbCO to total hemoglobin for 13 non-smoking mothers did not differ significantly from that for their infants (mean 0.38%, SD 0.26% vs 0.38%, SD 0.13%), but the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-01-01 00:00:00
abstract:BACKGROUND:In this study we demonstrate the technical application of flow cytometry and cell sorting combined with gene-rearrangement clonality profiling to detect and confirm minimal disease in 2 leukemia and 2 lymphoma cases. METHODS:Specimens with low percentages (0.05%-5%) of abnormal lymphoid populations were ide...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2005.061259
更新日期:2006-03-01 00:00:00
abstract::Pairs of values for serum triiodothyronine and serum triiodothyronine binding capacity were represented as maps of points for euthyroid populations (including subjects who were pregnant or were receiving estrogens) in the age groups 18-50, 51-64, 65-79, and greater than 80 years (504 subjects) and thyrotoxic populatio...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-10-01 00:00:00
abstract::The metabolism of the synthetic substrate 7-ethoxyresorufin is a selective measure of the activity of cytochrome P-448 monooxygenase, the subset of cytochrome P-450-mediated enzymes preferentially induced by polycyclic aromatic hydrocarbons and related compounds. 7-Ethoxycoumarin metabolism, on the other hand, reflect...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-09-01 00:00:00
abstract::This article reviews key advances in ion-selective electrode technology that have made potentiometric measurements of ionized calcium (Ca2+) reliable and precise. Our use of two second-generation Ca2+ analyzers (Radiometer ICA1 and NOVA 8) made possible uninterrupted service as volume increased to 31 640 patient tests...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1986-08-01 00:00:00
abstract::We describe an improved separation of the isoenzymes of aspartate aminotransferase (EC 2.6.1.1), based on ion-exchange chromatography. Involving the "Fast Protein Liquid Chromatography" system (Pharmacia) with a MonoQ column, this rapid, reproducible method for quantifying the mitochondrial enzyme shows good resolutio...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
abstract::In considering factors that might influence measurement of free thyroxin (T4), we evaluated the proportion (%) of T4 that could be stripped from thyroxin-binding globulin (TBG). The percentage of free T4 was measured in serially diluted sera from four normal subjects, four patients with hyperthyroidism or hypothyroidi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
abstract::We describe the interlaboratory testing of a candidate Reference Method (Part I) for uric acid in serum. The method is based on the ultrasound spectrophotometric quantitation of uric acid before and after incubation with uricase. A comprehensive investigation involving 12 laboratories was organized to document the tra...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-02-01 00:00:00
abstract::Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also desc...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-07-01 00:00:00
abstract::We examined the mechanism by which hypertriglyceridemia interferes with the Roche Diagnostics "Amylochrome" procedure for measurement of amylase in lactescent samples with normal and above-normal amylase activity. The serum blank recommended in the Amylochrome protocol to compensate for lactescence remains inappropria...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-10-01 00:00:00
abstract::The effect of serum-clot contact time on laboratory results was studied by dividing each blood specimen into four blood collection tubes. The control sera were separated from the clot within 30 min of the collection. The other tubes were incubated at 32 degrees C, and the sera were separated at 3, 6, and 24 h. The ser...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-06-01 00:00:00
abstract::A region consisting of 19 clinical laboratories harmonized their calibration of seven common enzymes by using fresh patient-pool sera. One of the laboratories was chosen to act as Regional Reference Laboratory (RRL). This laboratory used internationally accepted (mostly IFCC) methods at 37 degrees C, with an intralabo...
journal_title:Clinical chemistry
pub_type: 杂志文章,多中心研究
doi:
更新日期:1998-03-01 00:00:00
abstract:BACKGROUND:Uremic syndrome is the consequence of the retention of solutes usually cleared by the healthy kidneys. p-Cresol can be considered a prototypic protein-bound uremic toxin. It is conceivable, analogous with drugs, that the non-protein-bound fraction of p-cresol exerts toxicity. This aspect had never been evalu...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.3.470
更新日期:2003-03-01 00:00:00
abstract::We measured cyclosporine in whole blood from normal volunteers administered single oral doses of the drug and from two renal-transplant patients on immunosuppressive maintenance therapy, by liquid chromatography (I) and by radioimmunoassay with use of nonspecific polyclonal (II), specific monoclonal (III), and nonspec...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-12-01 00:00:00