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 microL), and supplies results in less than 7.5 min from injection. The intra-batch coefficient of variation for phenylalanine in human plasma samples (197-1104 mumol/L) ranged between 3.0% and 6.0% and the range of linearity was 10-1250 mumol/L for a 20-microL sample injection loop. The upper limit can readily be extended by using a smaller volume loop. Phenylalanine results from direct plasma injection (y) correlated well with those of a protein precipitation/HPLC technique (x): y = 0.931x + 46.4 (r = 0.951, n = 41, range 78-1344 mumol/L).
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Atherton NDsubject
Has Abstractpub_date
1989-06-01 00:00:00pages
975-8issue
6eissn
0009-9147issn
1530-8561journal_volume
35pub_type
杂志文章abstract：BACKGROUND:Although cardiac troponin (cTn) is a cornerstone marker in the assessment and management of patients with acute coronary syndrome (ACS) and heart failure (HF), cTn is not diagnostically specific for any single myocardial disease process. This narrative review discusses increases in cTn that result from acute...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2009.130799
更新日期：2009-12-01 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：:A novel noninstrumented technology (ChemTrak AccuMeter) for the quantitative measurement of analytes in biological fluids was reported at the 1990 Oak Ridge Conference (Clin Chem 1990;36:1591-7). This instrument-free technology has been adapted for the quantitative measurement of high-density lipoprotein (HDL). An in ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-09-01 00:00:00
abstract：BACKGROUND:Lectin-like oxidized LDL receptor 1 (LOX-1) is implicated in atherothrombotic diseases. Activation of LOX-1 in humans can be evaluated by use of the LOX index, obtained by multiplying the circulating concentration of LOX-1 ligands containing apolipoprotein B (LAB) times that of the soluble form of LOX-1 (sLO...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.140707
更新日期：2010-04-01 00:00:00
abstract：:We evaluated the Reflotron (Boehringer Mannheim) system for measuring activities of alanine aminotransferase (EC 2.6.1.2) and gamma-glutamyltransferase (EC 2.3.2.2). Within- and between-day precision were comparable with conventional analytical methods. The linear range of the methods extended to more than 40-fold the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-06-01 00:00:00
abstract：:We developed a solid-phase two-site immunoenzymometric assay (IEMA) of the estrogen-induced 52-kDa cathepsin D (EC 3.4.23.5) and its processed forms (48-kDa and 34-kDa proteins) in cytosols of breast cancer tissues, using two monoclonal antibodies directed against two different epitopes of these antigens. The first an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：:We describe a rapid polarization fluoroimmunoassay for screening for the presence of barbiturates in urine. The single reagent is prepared by pre-mixing antiserum with a fluorescein-labeled barbiturate derivative as tracer. Use of a mixture of two sheep antisera, raised against different barbiturate immunogens, result...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-11-01 00:00:00
abstract：:The formal definition of sensitivity associates the term with the change in the response of a system for a small change of the stimulus causing the response, i.e., the ratio of the response of a system to the stimulus causing it. One interpretation of sensitivity associates the rate of change of the response for a sma...
journal_title：Clinical chemistry
pub_type： 评论,杂志文章
doi：
更新日期：1997-10-01 00:00:00
abstract：:We evaluated a new EMIT II monoclonal amphetamine/methamphetamine assay for screening human urine by comparing it with the EMIT d.a.u. monoclonal amphetamine/methamphetamine assay and a fluorescence polarization assay. The EMIT II assay has a cutoff of 1 mg/L d-methamphetamine. The EMIT II and EMIT d.a.u. assays were ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-01-01 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：:To validate azotemic markers as an index for intradialytic changes in solute concentration, we compared eight solutes (pseudouridine, xanthine, hypoxanthine, peak 4, peak 5, p-hydroxyhippuric acid, indoxyl sulfate, and hippuric acid) with five classical azotemic markers (urea, creatinine, uric acid, phosphate, and pot...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：:Quinidine in serum was measured at 330 nm, after protein precipitation, with an alkyl phenyl reversed-phase chromatographic column by peak-height determination (external standards.) Sensitivity was 0.3 mg/liter, with linear response to at least 10 mg/liter serum. Interassay precision, measured on 20 consecutive days, ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
abstract：:In iron deficiency, zinc protoporphyrin (ZPP) is produced instead of heme, and the ZPP concentration in erythrocytes is increased (normal < or = 40 mumol/mol heme). We investigated the relevance of ZPP for staging iron deficiency. ZPP was determined by hematofluorometry in samples from 103 patients. Nineteen patients ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-05-01 00:00:00
abstract：:We used a modification of the polymerase chain reaction (PCR), involving two pairs of oligonucleotide primers, to detect a mutation in the low-density lipoprotein (LDL) receptor gene, commonly occurring among patients with familial hypercholesterolemia (FH) in Finland. This mutation, called FH-Helsinki, involves a lar...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-06-01 00:00:00
abstract：BACKGROUND:Disease-defining chromosomal translocations are seen in various neoplasms, especially in lymphomas and leukemias. Translocation detection at the DNA level is often complicated by chromosomal breakpoints that are distributed over very large regions. We have developed a ligation-based assay [the looped ligatio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.270140
更新日期：2017-07-01 00:00:00
abstract：:Serial results from an individual are often obtained using more than one method. Results should be transferable over time and locale. Every method has inherent analytical error, and goals are required to delineate the maximum allowable random (imprecision) and systematic (inaccuracy, bias) errors to facilitate optimal...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1992-11-01 00:00:00
abstract：:Four commercial products for urine glucose determination were evaluated and compared with a quantitative hexokinase procedure. We examined precision, sensitivity, and analytical recovery of glucose from glucose-supplemented urine samples and comparison of methods, using patients' samples. Only "Chemstrip uG" (Bio-Dyna...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-10-01 00:00:00
abstract：:The Glucose-Controlled Insulin Infusion System (Biostator) is a modular, computerized, feedback control system for dynamic control of blood glucose concentrations in diabetics. This on-line glucose analyzer for use with whole blood utilizes a novel enzyme (glucose oxidase)-membrane configuration and an electrochemical...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-08-01 00:00:00
abstract：:Of 98 patients' specimens examined for alkaline phosphatase (EC 3.1.3.1) isoenzymes by electrophoresis on cellulose acetate membrane after incubation with neuraminidase, 50 showed only a single liver or bone isoenzyme staining band; in 15 of these, the tissue origin of the fraction could not be accurately identified f...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-07-01 00:00:00
abstract：BACKGROUND:Several proteolytically derived fragments from the proline-rich region (PRR) of human inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) have been identified by surface-enhanced or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS or MALDI-TOF-MS) as potential diseas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.065722
更新日期：2006-06-01 00:00:00
abstract：BACKGROUND:The aims of this study were to measure the N-terminal fragment of pro-brain natriuretic peptide (proBNP) in plasma in medical conditions commonly found in primary care and to evaluate the utility of these measurements in identifying impaired cardiac function in elderly patients with symptoms associated with ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.8.1337
更新日期：2003-08-01 00:00:00
abstract：:We report a method for the extraction of angiotensin peptides from plasma with a mixture of acetone, 1 mol/L HCl, and water (40/1/5 by vol). The method is highly reproducible for the measurement of angiotensin I and angiotensin II in small sample volumes, with analytical recoveries of about 80% for both peptides. We i...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
abstract：:Measurements of alanine aminotransferase and aspartate aminotransferase with the SMAC were evaluated for correlation with the ABA-100, precision, linearity, and carryover. We assayed 200 specimens with normal and abnormal aminotransferase activities with both the SMAC (y) and the ABA-100 (X). Linear regression analysi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-05-01 00:00:00
abstract：:Total protein (TP), albumin (Alb), transferrin (TRF), retinol-binding protein (RPB), N-acetyl-beta-glucosaminidase (NAG), alanine aminopeptidase (AAP), gamma-glutamyltransferase (GGT), and creatinine (Cr) were measured in random (untimed) urine samples from 29 nonpregnant women and from pregnant subjects (11 in the fi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
abstract：:We describe an enzyme-linked immunosorbent assay for determination of light-chain ratios for IgG, IgA, and IgM in serum. A commercial serum with known overall kappa and lambda concentrations was used as standard. To capture the respective immunoglobulins, we used antibodies to gamma, lambda and mu chains coated onto m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：BACKGROUND:The B-type natriuretic peptides (BNP and N-terminal pro-BNP) are secreted by the heart and, in the case of BNP, serve to maintain circulatory homeostasis through renal and vascular actions and oppose many effects of the renin-angiotensin system. Recent evidence suggests that in patients with severe heart fai...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.210435
更新日期：2014-03-01 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：:Published estimates of the imprecision characteristics of immunoassays are often based on quantities of data that seem to be inadequate. The increasing use of imprecision profiles has not necessarily improved the situation. We describe and illustrate a method of computing 95% confidence intervals for profiles estimate...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
abstract：:The IFCC-recommended procedure for aspartate aminotransferase (EC 2.6.1.1) was adapted to the centrifugal analyzer and evaluated during five years. The main hindrance to widespread use of the recommended method is the need for pre-incubation with pyridoxal phosphate. The present method includes a 10-min pre-incubation...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-01-01 00:00:00
abstract：:Applying the principles of chemometrics can lead to development of a powerful, simple, comprehensive system for characterizing measurement reliability of analytical processes. The system described here consists of a format for specifications, definitions, and decision rules for evaluating and comparing analytical proc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
