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 to the analysis of urine from control rats and rats given L-canavanine, L-canavaninosuccinic acid, L-guanidinosuccinic acid, L-arginine, or urea, intraperitoneally. The recorder tracings are compared with those obtained for urine from healthy and uremic humans. After urea administration some guanidinosuccinate is excreted, along with substantial quantities of another substance that elutes just before guanidinosuccinate and so may be mistaken for it. Urine from uremic humans also shows this unidentified peak, but not urine from untreated rats or healthy humans. L-Canavanine gives rise, mainly, to guanidine and homoserine, apparently by reduction. Similarly, canavaninosuccinate is reduced to homoserine and guanidinosuccinate. Arginine gives rise to small quantities of guanidinosuccinate. Guanidinosuccinate is excreted mainly unchanged. When the guanidinosuccinate concentration is increased, excretion of guanidinoacetic acid is suppressed.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Natelson Ssubject
Has Abstractpub_date
1984-02-01 00:00:00pages
252-8issue
2eissn
0009-9147issn
1530-8561journal_volume
30pub_type
杂志文章abstract：BACKGROUND:Recurrent pregnancy loss, (RPL) affecting 1%-2% of couples, is defined as ≥3 consecutive pregnancy losses before 20-week' gestation. Women with RPL are routinely screened for etiological factors, but routine screening of male partners is not currently recommended. Recently it has been suggested that sperm qu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2018.289348
更新日期：2019-01-01 00:00:00
abstract：BACKGROUND:Our previously developed assay for detection of the factor V Leiden mutation (G1691A) based on a nucleic acid photo-cross-linking technology used two allele-specific capture probes and six fluorescein-modified signal-generating reporter probes. We wished to improve the sensitivity and performance of the meth...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.023556
更新日期：2004-02-01 00:00:00
abstract：BACKGROUND:Consideration of circulating biomarkers for risk stratification in heart failure (HF) is recommended, but the influence of atrial fibrillation (AF) on prognostic performance of many markers is unclear. We investigated the influence of AF on the prognostic performance of circulating biomarkers in HF. METHODS...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa287
更新日期：2021-01-08 00:00:00
abstract：:This method for assaying digoxin in serum with improved specificity combines small-column extraction of serum, "high-performance" liquid chromatography, and RIA of the eluted fractions. Analytical recoveries of 1.0, 0.5, and 0.1 microgram/L standards were 95%, 93%, and 84%, respectively. The CVs for duplicates and rep...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-08-01 00:00:00
abstract：:Lyophilized serum specimens were manufactured in such a way that fixed quantitative interspecimen relationships were established. The specimens were analyzed for about twenty constituents by several thousand laboratories in 1971, 1972, and 1973. Most of the consensus mean values derived from these analyses were found ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-07-01 00:00:00
abstract：:We describe a highly accurate and precise method for determination of total cholesterol in serum by isotope dilution/mass spectrometry. The method was developed for a Study Group of the Committee on Standards of the American Association for Clinical Chemistry, for use in establishing the accuracy of a candidate refere...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-06-01 00:00:00
abstract：:The pattern of organic acids in urine from 15 normal newborn infants was investigated by gas chromatography/mass spectrometry of trimethylsilylated derivatives. The urine contains large amounts of succinic, fumaric, 2-ketoglutaric, and 3-hydroxy-3-methylglutaric acids, which are all fairly small components of urine fr...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-01-01 00:00:00
abstract：:We report the results of a laboratory and clinical evaluation of a commercial kit procedure (Immuno Nuclear Corp.) for measuring the mid-region of the parathyrin molecule. The estimated dose at 50% binding averaged 130 pmol/L, and the minimum detectable concentration was 14 pmol/L. The within-assay CV was less than or...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-11-01 00:00:00
abstract：:We describe a multiprobe colorimeter that permits the reading of enzyme-linked immunosorbent assays (ELISA) in situ, by use of microhemagglutination plates. The use of dipping probes eliminates interference from meniscus effects and air-bubble entrapment. Detailed validation tests have been done and potential sources ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-04-01 00:00:00
abstract：:Using 123 specimens, we compared the concordance of three different methods for determining glycohemoglobin (GHb): the Diamat (Bio-Rad Laboratories), an automated analyzer measuring HbA1c by cation-exchange chromatography; an assay with the IMx analyzer (Abbott Laboratories), based on boronate affinity binding; and an...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-02-01 00:00:00
abstract：:This solid-phase competitive europium immunoassay of progesterone in plasma relies on antigen labeling. With this new approach, time-resolved fluoroimmunoassay can attain sensitivity and precision similar to that of conventional radioimmunoassay. The europium-labeling involves coupling diethylenetriaminepentaacetic ac...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-03-01 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：INTRODUCTION:Commercially available SARS-CoV-2 serological assays based on different viral antigens have been approved for the qualitative determination of anti-SARS-CoV-2 antibodies. However, there are limited published data associating the results from commercial assays with neutralizing antibodies. METHODS:67 speci...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa211
更新日期：2020-09-07 00:00:00
abstract：:The time-course of the contamination of exogenous hydrogen from cigarette smoke on postprandial breath hydrogen concentration was evaluated in 10 subjects, six regular smokers and four occasional smokers. Breath hydrogen values were determined by gas chromatography 10 min, 5 min, and immediately prior to smoking a fil...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-11-01 00:00:00
abstract：BACKGROUND:C-reactive protein (CRP), the prototypic marker of inflammation, is present in atherosclerotic plaques and appears to promote atherogenesis. Also, CRP has been localized to monocytes and tissue macrophages, which are present in the necrotic core of lesions prone to plaque rupture. Leukocyte-derived myelopero...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.109207
更新日期：2009-02-01 00:00:00
abstract：:We measured thyroid hormones and thyroxin-binding proteins in serum from 62 normal lactating and 52 nonlactating women at three months postpartum, and compared these values with those for 42 nonpregnant control women of similar age. Mean thyroxin concentrations in the lactating and nonlactating women were significantl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-07-01 00:00:00
abstract：BACKGROUND:The sex differential in coronary heart disease (CHD) risk, which is not explained by male/female differences in lipid and lipoprotein concentrations, narrows with age. We examined whether this differential CHD risk might, in part, be attributable to the sizes of lipoprotein particles or concentrations of lip...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.032763
更新日期：2004-07-01 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：:A total of 1357 polypeptides [946 acidic (isoelectric focusing) and 411 basic (nonequilibrium pH-gradient electrophoresis)] from human HeLa cells have been separated and catalogued with use of high-resolution two-dimensional gel electrophoresis. Of these polypeptides, 1266 were detected by labeling cells with [35S]met...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：BACKGROUND:We have developed a silicon-based biosensor that generates a visual signal in response to nucleic acid targets. METHODS:In this system, capture oligonucleotide probes are immobilized on the surface of the biosensor. Interaction of the capture probes with a complementary target and a biotinylated detector ol...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
abstract：BACKGROUND:Evidence suggests that systemic inflammation may adversely impact HDL function. In this study we sought to evaluate the independent and incremental predictive performance of GlycA-a novel serum inflammatory biomarker that is an aggregate measure of enzymatically glycosylated acute phase proteins-and HDL subc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.261636
更新日期：2017-01-01 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：:In this paper, we present initial quality-control evaluations for a prototype clinical laboratory, recommendations for clinical and technical data record-keeping, and laboratory protocols designed to minimize operator-dependent analytical error in a multi-user environment. These evaluations and recommendations are bas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-12-01 00:00:00
abstract：:We have designed and constructed a digital matrix photometer for quantitative measurement of reflected light of small chromophoric areas or colored spots. The areas are divided conceptually into small subunits in which the reflected light is measured. This is done through stepwise scanning with a photodiode array. The...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-06-01 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：BACKGROUND:Because reference values for vitamin B(12) concentrations and vitamin B(12)-binding capacities for pregnant women have not been established, the reference values for nonpregnant women are often applied to assess vitamin B(12) status. The aim of the present study was to describe ranges of biochemical indices ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-06-01 00:00:00
abstract：:The location of the Reference Value for an analyte within the population distribution affects the magnitude of error due to methodological bias. Using the gaussian distribution, we evaluated the effects of systematic and proportional biases of the method (positive and negative), mean value, and standard deviation on t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-11-01 00:00:00
abstract：BACKGROUND:Previous methods to measure glycohemoglobin (GHb) have been time-consuming or imprecise; we therefore developed a new enzymatic assay for GHb. METHODS:Blood cells were first hemolyzed, and hemoglobin was digested with protease to yield fructosyl amino acid. Fructosyl amino acid oxidase acts on the fructosyl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.2.269
更新日期：2003-02-01 00:00:00
abstract：BACKGROUND:In patient and population samples, generation of analytical results that are comparable and independent of the measurement system, time, and location is essential for the utility of laboratory information supplied in healthcare. Obtaining analytical measurement results with such characteristics is the aim of...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2008.107052
更新日期：2009-06-01 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
