Abstract:
:We analyzed pancreatic enzyme data from 508 patients with suspected pancreatitis by neural network analysis, by an Expert multirule generation protocol, and by receiver-operator characteristic (ROC) curve analysis of a single test result. Neural network analysis showed that use of lipase provided the best means for diagnosing pancreatitis. Diagnostic accuracies achieved by using amylase only, lipase only, and amylase and lipase in combination were 76%, 82%, and 84%, respectively. Use of the Expert rule generation protocol provided a diagnostic accuracy of 92% when rules for single and multiple samplings were combined. ROC curve analysis for initial enzyme activities showed the maximal diagnostic accuracy to be 82% and 85% for amylase and lipase, respectively; use of peak enzyme activities yielded accuracies of 81% and 88%, respectively. The evaluation of laboratory test data should include analysis of the diagnostic accuracy of laboratory tests by multivariate techniques such as neural network analysis or an Expert systems approach. Multivariate analysis should allow for a more realistic assessment of the diagnosis accuracy of laboratory tests because all the available data are included in the evaluation.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Kazmierczak SC,Catrou PG,Van Lente Fsubject
Has Abstractpub_date
1993-09-01 00:00:00pages
1960-5issue
9eissn
0009-9147issn
1530-8561journal_volume
39pub_type
杂志文章abstract::Because of uncertainty as to the molecular weight of transferrin, a previous comparison [Von der Heul et al., Clin. Chim. Acta 38, 347 (1972)] between transferrin content of serum and total iron-binding capacity cannot be definitive. We found a conversion factor for expressing the maximum amount of iron bound by 1 mg ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-07-01 00:00:00
abstract::The Axial Separation Module (ASM), which separates whole-blood specimens serially in Axial Process Containers (APC), was evaluated for clinical performance at the University of Virginia Health Sciences Center (UVA HSC) in a community-based outpatient laboratory (North Ridge Clinic). We hypothesized that moving the tas...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1997-02-01 00:00:00
abstract:BACKGROUND:Simple, reproducible assays are needed for the quantification of sphingolipids, ceramide (Cer), and sphingoid bases. We developed an HPLC method for simultaneous quantification of total plasma concentrations of Cer, glucosylceramide (GlcCer), and ceramide trihexoside (CTH). METHODS:After addition of sphinga...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.079012
更新日期:2007-04-01 00:00:00
abstract::A high (2.0 mol/L) NaCl concentration apparently suppresses the secondary-site binding of bilirubin by human serum albumin. Thus if an excess of bilirubin is added to human serum albumin or to neonatal serum in buffer containing 0.1 mol of tris(hydroxymethyl)aminomethane and 2.0 mol of NaCl per liter (pH 7.5), and the...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-01-01 00:00:00
abstract::A rapid and precise immunoassay for quantification of total homocysteine in blood samples is presented. The method avoids the use of radioisotopes and chromatographic separations and relies on enzymatic conversion of homocysteine to S-adenosyl-L-homocysteine, followed by quantification of S-adenosyl-L-homocysteine by ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::This communication describes and evaluates an improved routine methodology for quantitating clinical proteinuria. Based on investigations of Piscator and of Savory et al., a modified Tsuchiya's reagent (ethanolic HCI-phosphotungstic acid) is used to precipitate proteins at 56 degrees C, followed by biuret spectrophoto...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-03-01 00:00:00
abstract:BACKGROUND:Optimal cutoff values for tests results involving continuous variables are often derived in a data-driven way. This approach, however, may lead to overly optimistic measures of diagnostic accuracy. We evaluated the magnitude of the bias in sensitivity and specificity associated with data-driven selection of ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2007.096032
更新日期:2008-04-01 00:00:00
abstract:BACKGROUND:The emergence of a novel pandemic human strain of influenza A (H1N1/09) has clearly demonstrated the need for flexible tools enabling the rapid development of new diagnostic methods. METHODS:We designed a set of reverse-transcription quantitative real-time PCR (RT-qPCR) assays based on the Universal ProbeLi...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2009.136192
更新日期:2009-12-01 00:00:00
abstract::Determination of the concentration of erythrocyte folate by means of competitive protein binding assay critically depends on the extraction procedure applied. Results will be influenced by variable factors such as the in vitro age of the blood samples, the degree of hemolysis, the presence of ascorbic acid, and the pH...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-07-01 00:00:00
abstract::We describe the conjoint measurement in urine of the alcoholic catecholamine metabolites 3,4-dihydroxyphenylglycol (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG). The method involves extraction with ethyl acetate and back-extraction into acetic acid (MHPG), followed by adsorption onto alumina (DHPG). The separation...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-05-01 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::We have modified an automated measurement system of urinary iodine (UI) and established a sensitive UI assay system by using ultraviolet (UV) digestion. The automated system is sensitive enough to detect concentrations of UI < 0.78 mumol/L (< 10 micrograms/dL) in a small volume of urine (500 microL). Sample throughput...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract::In this automated apoenzyme reactivation immunoassay system (Ames Optimate) for thyroxin-binding globulin (TBG), the sample and N6-aminohexylflavin adenine dinucleotide-labeled TBG react sequentially with antiserum. Then apoglucose oxidase is added to combine with the free fraction and generate glucose oxidase activit...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-05-01 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::A rapid technique (5-10 min) has been developed for fractionating nucleotides from base and nucleoside contaminants in acid extracts of cells, by adsorption to silica gels. Silica gels (1-mL bed volume) were washed with 5 mL of water then with 5 mL of acetonitrile/water (90/10 by vol). After applying 3-mL samples, adj...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-09-01 00:00:00
abstract::Clinically relevant interassay precision profiles for thyrotropin (thyroid-stimulating hormone; TSH) were constructed with human serum pools measured over 4-8 weeks by six immunometric assays, in at least two different reagent lots. Functional sensitivities (the concentration at which the interassay CV is < or = 20%) ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-03-01 00:00:00
abstract::Comparison of two methods for determining a substance is a common procedure in clinical chemistry. Almost without exception, normal theory statistics are used with the tacit assumption that the data under test show gaussian distributions. Experience has led us to question this assumption for populations of differences...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-03-01 00:00:00
abstract::Urinary acidic and alcoholic catecholamine metabolites were isolated separately from 24-h urines by simple extraction procedures. After derivatization, extracts were analyzed by means of simultaneous gas chromatography on two different stationary phases. The quality of the assay was checked by running "normal" and enr...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-05-01 00:00:00
abstract::We describe a liquid-chromatographic procedure for simultaneously determining eight steroids in serum. We used a Zorbax ODS column and a mobile phase of methanol/isopropanol/water (44/10/46, by vol), which well resolves the steroids cortisone, cortisol, corticosterone, 11-deoxycortisol, 11-deoxycorticosterone, androst...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-08-01 00:00:00
abstract:BACKGROUND:Analysis of fetal DNA in maternal plasma has recently been introduced as a new method for noninvasive prenatal diagnosis, particularly for the analysis of fetal genetic traits, which are absent from the maternal genome, e.g., RHD or Y-chromosome-specific sequences. To date, the analysis of other fetal geneti...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.029835
更新日期:2004-06-01 00:00:00
abstract:BACKGROUND:TMPRSS2:ERG fusions are promising prostate cancer biomarkers. Because they can occur in multiple forms in a single cancer specimen, we developed a quantitative PCR test that detects both type III and type VI TMPRSS2:ERG fusions. The assay is quantified from a standard curve determined with a plasmid-cloned t...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.108845
更新日期:2008-12-01 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::Several factors can limit the use of therapeutic drug monitoring (TDM) for cancer chemotherapeutic agents, including poorly defined concentration-effect relationships for many antineoplastic agents. This is further complicated by cancer being a highly heterogeneous group of diseases, each of which may have a unique co...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::We describe a rapid, sensitive, and specific "high performance" liquid chromatographic analysis for disopyramide and its mono-N-dealkylated metabolite in serum, urine, and saliva. We used a mu-Bondapak CN column and an acetate buffer mobile phase containing methanol. Retention times for the two compounds and the inter...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-03-01 00:00:00
abstract:BACKGROUND:Reports of the use of multiplex enzyme assay screening for Pompe disease, Fabry disease, Gaucher disease, Niemann-Pick disease types A and B, and Krabbe disease have engendered interest in the use of this assay in newborn screening. We modified the assay for high-throughput use in screening laboratories. ME...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.104711
更新日期:2008-10-01 00:00:00
abstract::The method is based on the selective activating capacity of dithiothreitol on creatine kinase isoenzyme MB, after isoenzyme MM is activated by glutathione. Isolated isoenzymes MM and MB of human and canine origin were assayed individually and in mixtures of known activities. When glutathione was present in the assay m...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-10-01 00:00:00
abstract::In radioimmunoassay of digoxin by the dextran-coated charcoal method, duration of the incubation period for the antigen-antibody reaction and time allowed for dextran-coated charcoal to absorb the free antigen are critical factors. We compared effects of prolonged periods of absorption on results obtained with five co...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-02-01 00:00:00
abstract::Iron-depleted donors are at increased risk of developing anemia; if these donors could be identified by a screening test, iron supplementation or decreased donation frequency could be considered. Tests to determine serum ferritin, blood hemoglobin, and erythrocyte (Erc)-zinc protoporphyrin concentrations were examined...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-06-01 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:BACKGROUND:Testing for troponin has important clinical value for patients who present with typical symptoms of acute coronary syndromes (ACS) such as chest pain (CP). Much less is known about the value of troponin testing for patients who present with other symptoms of ACS (anginal equivalent symptoms). METHODS:The ut...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.016311
更新日期:2004-01-01 00:00:00