Abstract：
:Ammonia concentrations in plasma may increase because of contamination and deterioration of blood components during specimen handling and storage. Using replicate specimens from healthy volunteers, we studied influences of specimen processing and storage procedures on ammonia measurements made with a self-contained reagent system. Under some conditions, ammonia concentrations more than doubled. The use of nonhemolyzed plasma specimens and prompt centrifugation, separation of plasma, and ammonia determination apparently were important in avoiding such increases, the duration of contact between plasma and cells being the most important factor. Lower temperatures had minimal effect on whole-blood storage and centrifugation, but retarded increases in ammonia in stored plasma. We conclude that procedures for collection and storage of specimens for ammonia determinations should be standardized and strictly observed.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Howanitz JH,Howanitz PJ,Skrodzki CA,Iwanski JAsubject
Has Abstractpub_date
1984-06-01 00:00:00pages
906-8issue
6eissn
0009-9147issn
1530-8561journal_volume
30pub_type
杂志文章abstract：BACKGROUND:Newborn screening for deficiency in the lysosomal enzymes that cause Fabry, Gaucher, Krabbe, Niemann-Pick A/B, and Pompe diseases is warranted because treatment for these syndromes is now available or anticipated in the near feature. We describe a multiplex screening method for all five lysosomal enzymes tha...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.035907
更新日期：2004-10-01 00:00:00
abstract：:In "flow-injection analysis," the sample is inserted into a stream of reagent by use of a sample-injection valve. Mixing occurs downstream from the valve in a coil of tubing. With chemiluminescence detection this coil is positioned in front of a photomultiplier. We have evaluated the system for detection of hydrogen p...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-09-01 00:00:00
abstract：:The human ras gene plays a fundamental role in the transduction of extracellular signals to the nucleus, thereby regulating cell growth and differentiation. Point mutations in the ras gene convert it into a transforming oncogene that has been found in many solid and hematologic malignancies. We describe a rapid and se...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-05-01 00:00:00
abstract：BACKGROUND:Eph receptors and their ligands, the ephrins, represent a large class of cell-cell communication molecules with well-defined developmental functions. Their role in healthy adult tissues and in human disease is still largely unknown, although diverse roles in carcinogenesis have been postulated. METHODS:We e...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.026849
更新日期：2004-03-01 00:00:00
abstract：BACKGROUND:Cerebrospinal fluid (CSF) tau is a common biomarker for Alzheimer disease (AD). Measurements of tau have historically been performed using immunoassays. Given the molecular diversity of tau in CSF, the selectivity of these immunoassays has often been questioned. Therefore, we aimed to develop an analytically...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.216515
更新日期：2014-04-01 00:00:00
abstract：:We used ion-exchange column chromatography and electrophoresis on polyacrylamide gel to compare the acid phosphatase isoenzymes of prostate and leukocytes. The major isoenzyme of the prostate is band 2A; only a trace of band 2B was observed. However, the major isoenzymes of leukocytes are band 4 and band 2B, and only ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-07-01 00:00:00
abstract：BACKGROUND:Recent studies have suggested that single-stranded DNA (ssDNA) library preparation can enrich short DNA species from the plasma of healthy individuals, cancer patients, and transplant recipients. Based on previous observations that fetal DNA molecules in the maternal plasma are shorter than maternal DNA mole...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2016.268656
更新日期：2017-05-01 00:00:00
abstract：:Controversy regarding the presence of a circadian rhythm in unconjugated estriol in serum during pregnancy led us to study the possibility that the observed rhythms actually are the result of partitioning of estriol into serum lipids when these increase postprandially. Addition of triglycerides to purified estriol sta...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-02-01 00:00:00
abstract：BACKGROUND:Few data compare cardiac troponin T (cTnT) and cardiac troponin I (cTnI) in a general population. We sought to evaluate the distribution and association between cTnT, cTnI, and cardiovascular risk factors in a large general population cohort. METHODS:High-sensitivity cTnT and cTnI were measured in serum fro...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2018.292086
更新日期：2018-11-01 00:00:00
abstract：:This assay was developed to measure apolipoprotein (apo) B in blood samples spotted onto filter paper. The long-term aim is to detect young families with the dominantly inherited familial hypercholesterolemia, during current neonatal screening programs. The interassay CV was 5.6%, and apo B concentrations correlated c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-06-01 00:00:00
abstract：:The use of 4-chlorotestosterone acetate by farmers for cattle fattening was recently demonstrated although the use of this anabolic steroid is strictly forbidden in the European Union. We investigated the metabolism of 4-chlorotestosterone acetate in the bovine species after intramuscular and oral administration. Nine...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-05-01 00:00:00
abstract：:We have evaluated a new immunoenzymatic assay for human thyrotropin involving three monoclonal antibodies (Abbott HTSH EIA) and compared the results with those of two conventional nonequilibrium double-antibody radioimmunoassay (RIA) methods: Clinical Assays' RIA and a research RIA (J Clin Endocrinol Metab 1975; 41:67...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-03-01 00:00:00
abstract：:We compared a stabilized-temperature L'vov platform furnace containing an end-heated graphite atomizer (HGA) and transverse Zeeman background-correction system with a side-heated furnace system (transversely heated graphite atomizer; THGA) containing a longitudinal Zeeman background-correction system for the determina...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-03-01 00:00:00
abstract：BACKGROUND:External quality assurance (EQA) programs for diagnostic tests based on nucleic acid amplification have not been widely implemented in clinical laboratories and remain limited to few tests. Development of specific EQA programs based on application-based proficiency testing for any diagnostic molecular target...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.5.782
更新日期：2003-05-01 00:00:00
abstract：:We modified the liquid-chromatographic assay of Schleicher and Wieland (J Clin Chem Clin Biochem 1981; 19:81-7) for measuring lysine-bound glucose in serum proteins, increasing its performance and practicality. After precipitating serum proteins from 10- to 50-microL samples with ethanol (700 mL/L) and hydrolyzing the...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-09-01 00:00:00
abstract：BACKGROUND:Buprenorphine is under investigation as a pharmacotherapeutic agent for treating opioid dependence in pregnant women. We hypothesized that there would be a relationship between the cumulative maternal dose of buprenorphine during pregnancy and the concentration of buprenorphine and norbuprenorphine in matern...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2007.091413
更新日期：2007-12-01 00:00:00
abstract：BACKGROUND:Plasma creatinine concentration and calculated creatinine clearance are of limited value as glomerular filtration rate (GFR) markers in patients with decompensated liver cirrhosis. We assessed plasma cystatin C as an indicator of GFR in such patients. METHODS:We studied 36 patients with decompensated liver ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-06-01 00:00:00
abstract：BACKGROUND:Cardiovascular mortality is markedly higher in Russia than in Western Europe and the US. Little is known about indicators of atherosclerotic risk in the Russian population. To our knowledge, this is the first study of apolipoprotein (apo) AI and B in Russia based on the WHO-IFCC standard. METHODS:We measure...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2003.023853
更新日期：2004-02-01 00:00:00
abstract：:The fructosamine test is considered clinically useful for assessing short-term integrated control of blood glucose, but there are few published data to support this hypothesis. We fractionated glycated and nonglycated proteins by affinity chromatography on phenylboronate columns and, with specific immunochemical metho...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 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 determined estrogen receptor protein and carcinoembryonic antigen in cytosols prepared from 189 human breast carcinoma tissues, 85 benign or normal breast biopsies, and 101 tissue specimens metastatic from breast carcinoma. Carcinoembryonic antigen was observed in 70% of the primary carcinomatous tissues, 15% of th...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-08-01 00:00:00
abstract：:Plasma hydroxyproline fractions--free-plus-peptide and free--were determined by a method involving centrifugal ultrafiltration and the procedure of Kivirikko et al. [Anal. Biochem. 19, 249 (1967)]. Within- and between-day precision (CV) for the combined fractions was 4--5% and 2.8--6%, respectively. Mean analytical re...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
abstract：:We describe a method for measuring apolipoprotein (apo) C distribution between apo B-containing lipoprotein (apo B-LP) and non-apo B-LP. The procedure requires the precipitation of apo B-LP, the redissolution of the pellet, and the quantification of C peptides in the redissolved pellet. The ratio of apo C in non-apo B...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-02-01 00:00:00
abstract：:Extensive data implicate cholesterol in the atherosclerotic process responsible for coronary disease. Of the atherosclerotic disease outcomes, serum cholesterol is most strongly related to coronary disease. A significant relationship of serum cholesterol to all clinical manifestations of coronary heart disease has bee...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1988-01-01 00:00:00
abstract：:To secure a successful product in today's era of cost containment, manufacturers and developers of new in vitro diagnostic technologies must consider payment issues--coverage and reimbursement by healthcare insurers--as critical market forces that must be addressed in the business plan. Similar to the regulatory hurdl...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-09-01 00:00:00
abstract：BACKGROUND:Studies of the effects of tobacco smoke often rely on reported exposure to cigarette smoke, a measure that is subject to bias. We describe here the relationship between parental smoking exposure as assessed by urinary cotinine excretion and lung function in children with asthma. METHODS:We studied 90 childr...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：
更新日期：1999-04-01 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：:A reaction of urea, o-phthalaldehyde and N-(1-naphthyl)ethylenediamine is described for measurement of urea by manual, continuous-flow, and kinetic methods. The continuous-flow system requires 25 mu-l of sample; 40 samples can be analyzed per hour. The kinetic method requires no enzymes, has no lag phase, and has good...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-07-01 00:00:00
abstract：:Nitric oxide is a soluble gas continuously synthesized by the endothelium. This substance has a wide range of biological properties that maintain vascular homeostasis, including modulation of vascular dilator tone, regulation of local cell growth, and protection of the vessel from injurious consequences of platelets a...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1998-08-01 00:00:00
abstract：BACKGROUND:The recent discovery of the presence of circulating cell-free fetal DNA in maternal plasma opens up new prenatal diagnostic applications and provides new avenues for clinical investigation. It is of research and potential diagnostic interest to determine whether fetal trisomy 21 may be associated with quanti...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,多中心研究
doi：
更新日期：1999-10-01 00:00:00
