Abstract：
:A precolumn derivatization method was optimized for rapid and specific analysis of total urinary hydroxyproline by HPLC. After an overnight hydrolysis, urine samples dried and reconstituted with the internal standard cysteic acid (in sodium hydrogen carbonate, pH 9.3) were derivatized with N,N-diethyl-2,4-dinitro-5-fluoroaniline (FDNDEA) at 100 degrees C for 20 min. The DNDEA-hydroxyproline adduct was separated on an Ultrasphere ODS column with a mobile phase of acetate buffer (containing triethylamine, 6 mL/L, pH 4.3) and acetonitrile (80/20, by vol), and was detected at 360 nm. A single run took 18 min with a hydroxyproline retention time of 7.3 min. The assay showed a linear response to hydroxyproline concentrations from 5 to 100 mg/L with a detection limit of 0.8 ng injected, corresponding to 2 mg/L in urine. Mean (SD) analytical recovery was 94.2 (13)% and 104 (9)% at 10 and 50 mg/L, respectively. Within-run and between-run CVs (n = 10) were 3.74% and 4.33%, respectively, for 25 mg/L. Results for samples (n = 50) analyzed by HPLC (y) vs ion-exchange chromatography with postcolumn ninhydrin reaction (x) correlated well: y = 0.98x + 1.02 (r = 0.985, Sxy = 3.13). In another comparison, involving 173 samples, a colorimetric procedure (Hypronosticon, x) gave slightly higher values than the HPLC method (y): y = 0.83x + 2.21 (r = 0.937, Sxy = 4.6).
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Paroni R,De Vecchi E,Fermo I,Arcelloni C,Diomede L,Magni F,Bonini PAsubject
Has Abstractpub_date
1992-03-01 00:00:00pages
407-11issue
3eissn
0009-9147issn
1530-8561journal_volume
38pub_type
杂志文章abstract：:We describe a procedure based on equilibrium dialysis that allows the simultaneous determination of free testosterone and testosterone bound to non-sex-hormone-binding globulin (non-SHBG) in plasma. After saturating SHBG with 5 alpha-dihydrotestosterone (DHT) according to a technique recently described, the percentage...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-06-01 00:00:00
abstract：:Intra- and interindividual components of biological variation have been determined for total thyroxin (TT4), free thyroxin (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyrotropin (TSH). Calculated analytical goals (CV, %) for the precision required for optimal patient care are: TT4 less than ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-06-01 00:00:00
abstract：BACKGROUND:The susceptibility of plasma lipids to oxidation is thought to be a factor contributing to atherogenic risk. Various groups have studied the in vitro oxidizability of isolated LDL and examined the effects of conventional antioxidants. The drawbacks associated with the isolation of LDL for evaluation of in vi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.051078
更新日期：2005-11-01 00:00:00
abstract：:We describe a case of sulfhemoglobinemia associated with toxic paint ingestion. Blood gases, oxygen content, and fractional hemoglobin derivatives were assayed with Radiometer 520 and OSM3 instruments. Although the CO-oximeters indicated the presence of sulfhemoglobin (SulfHb), the results were not quantitative. An OS...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-01-01 00:00:00
abstract：BACKGROUND:In recent years, a large number of studies have been published on the performance of glucose monitors. The quality of these reports is not known. METHODS:We searched the PubMed database for performance evaluations of handheld glucose monitors published from August 2002 to November 2006. Relevant articles we...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2006.083493
更新日期：2007-06-01 00:00:00
abstract：:We measured advanced glycosylation end products in the mesenteric artery of 37 patients (ages 29-82 years), 34 of whom were nondiabetic. Samples of arterial tissue were obtained during bowel resectioning. Advanced glycosylation end products were measured as collagen-linked fluorescence (excitation wavelength 370 nm, e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-04-01 00:00:00
abstract：:A simple and convenient method using commercially available derivatization reagents is described for the measurement of betaine and N,N-dimethylglycine (DMG) in blood and urine. Precolumn derivatization of plasma or urine is performed directly in acetonitrile without extraction with p-bromophenacyl bromide and crown e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:We studied 25 borderline-hyperparathyroidism patients whose total serum calcium concentration was within normal limits (reference range: 2.25--2.75 mmol/liter) but whose concentrations of serum ionized calcium were above normal (reference range: 1.03--1.23 mmol/liter). Their hyperparathyroidism was histopathologically...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-11-01 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：:This HPLC/immunoassay procedure measures digoxin in serum with no interference from digoxin metabolites or digoxin-like factors. We used solid-phase (C18 and Diol) extraction, a C18 column with a tetrahydrofuran/water mobile phase, and final quantification by fluorescence polarization immunoassay. Deslanoside and gito...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-12-01 00:00:00
abstract：:We developed a fluorometric method for determining delta-aminolevulinic acid (ALA) in urine of lead workers. A high-performance liquid chromatograph (HPLC) equipped with a fluorescence HPLC monitor is used. The detection limit for aqueous ALA is 20 micrograms/L (15 pmol of ALA in the 100-microL sample). The working li...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-09-01 00:00:00
abstract：BACKGROUND:With the gradual reopening of economies and resumption of social life, robust surveillance mechanisms should be implemented to control the ongoing COVID-19 pandemic. Unlike RT-qPCR, SARS-CoV-2 whole genome sequencing (cWGS) has the added advantage of identifying cryptic origins of the virus, and the extent o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa187
更新日期：2020-11-01 00:00:00
abstract：:This method for determining aluminum in human serum involves electrothermal atomic absorption spectrophotometry. A longer drying time allows less pre-dilution of the sample, and the method also includes a flush cycle after atomization. Standard-addition methodology is used to eliminate matrix effects and the need for ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-06-01 00:00:00
abstract：:We evaluated a new agarose-gel-electrophoretic procedure (Corning) (I) for separating and quantitating of high-density lipoprotein cholesterol (HDLC), comparing it with the modified Lipid Research Clinics (LRC) procedure (heparin 183 kilounits/L, MnCl2 92 mmol/L) (II). Method I was insensitive to an HDLC concentration...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-11-01 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：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
abstract：BACKGROUND:Urinary cross-linked N-telopeptide of type I collagen (NTX) is a reliable bone resorption marker in patients with metabolic bone disease. We assessed a clinically available serum NTX assay suitable for anuric patients on hemodialysis (HD). METHODS:Serum concentrations of NTX, C-terminal telopeptide of type ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.051524
更新日期：2005-12-01 00:00:00
abstract：BACKGROUND:Soluble CD146 (sCD146), is an endothelial marker with similar diagnostic power as natriuretic peptides in decompensated heart failure (HF). While natriuretic peptides are released by the failing heart, sCD146 may be released by veins in response to stretch induced by systemic congestion in HF. This study inv...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2016.260471
更新日期：2017-01-01 00:00:00
abstract：:We describe specifications for high-purity 4-nitrophenol, which is suitable for spectrophotometric standardization. Such a reference material is needed in clinical enzymology to establish the proper molar absorptivity of 4-nitrophenol under final reaction conditions, particularly for measuring alkaline phosphatase act...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-05-01 00:00:00
abstract：:Serum concentrations of apolipoprotein (apo) B and apo A-I were measured from 1985-1996 in a Swedish population sample of 83 112 males and 64 464 females, ages <20 to >80 years, using an automated immunoturbidimetric method calibrated against fresh pools of human serum and commercial calibrators. All values were recal...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-08-01 00:00:00
abstract：:We studied the pattern of acute-phase proteins (orosomucoid, C-reactive protein, and haptoglobin) in hepatocellular deficiency due to chronic alcohol consumption, characterized by a decrease in serum transferrin concentration. We found that their patterns could vary independently of hepatocellular deficiency, but depe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-01-01 00:00:00
abstract：:Zinc is determined in neutrophils and lymphocytes (isolated from whole blood on discontinuous gradients of Ficoll-Hypaque) and in microliter quantities of plasma and erythrocytes by flameless atomic absorption spectrophotometry with greater sensitivity than with conventional flame atomic absorption spectrophotometry. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-03-01 00:00:00
abstract：:During phase I/II clinical trials of sirolimus (rapamycin; SRL), therapeutic drug monitoring was performed with a multistep liquid-liquid extraction of 1-mL aliquots of whole blood followed by reversed-phase HPLC with ultraviolet detection. Blood was sampled according to a standardized protocol and clinical status. SR...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-12-01 00:00:00
abstract：:We report a continuous-flow fluorometric method for total urinary estrogens that involves the Kober reaction, with extraction of the reaction product into dichloroethane containing trichloroacetic acid as described by Hahnel and Jones [Clin. Chim. Acta 16, 185 (1967)]. The dichloroethane extraction gives greater stabi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-10-01 00:00:00
abstract：:Parathyroid hormone-related protein (PTHrP) was measured in plasma by a new immunoradiometric assay (IRMA) from Nichols Institute. The assay is specific for PTHrP and shows excellent parallelism when measuring keratinocyte fluid, samples with high PTHrP content, and PTHrP-supplemented plasma. A precision profile estab...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-03-01 00:00:00
abstract：:The Dutch Foundation for Quality Assessment in Clinical Chemistry (SKZL) is the professional organization that conducts external quality-assessment schemes in The Netherlands. However, such schemes in fact assess the performance of the internal quality-control systems of the participating laboratories. In this paper w...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-07-01 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：:Total bilirubin is determined here with a multipoint calibration approach and with use of Standard Reference Material No. 916 bilirubin from the National Bureau of Standards. The bilirubin calibration solutions prepared in solutions of Cohn Fraction V human albumin were stable for at least one year when stored at -80 ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-08-01 00:00:00
abstract：BACKGROUND:This Case Conference reviews the normal changes in thyroid activity that occur during pregnancy and the proper use of laboratory tests for the diagnosis of thyroid dysfunction in the pregnant patient. CASE:A woman in the 18th week of pregnancy presented with tachycardia, increased blood pressure, severe vom...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1999-12-01 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
