Abstract：
:To establish optimum conditions for creatine kinase (EC 2.7.3.2) activity measurement with the creatine phosphate in equilibrium creatine reaction, we re-examined all kinetics factors relevant to an optimal and standardized enzyme assay at 30 and 25 degrees C. We determined the pH optimum in vaious buffers, considering the effect of the type and concentration of the buffer, as well as the influence of various buffer anions on the activity. The relation between activity and substrate concentration was shown and the apparent Michaelis constants of creatine kinase for creatine phosphate and ADP were evaluated. We tested the effect on creatine kinase measurement of the concentration of substrates (glucose and NADP+) in the auxillary and indicator reactions, especially the influence of the added auxiliary (hexokinase) and indicator (glucose-6-phosphate dehydrogenase) enzymes on the lag phase, at different temperatures. The NADP+ concentration proved to be the factor limiting the duration of constant reaction rate. We studied the inhibition of creatine kinase and adenylate kinase by AMP and established a convenient AMP concentration. For reactivation of creatine kinase, N-acetyl cysteine as sulfhydryl compound was introduced. Finally, we examined the relationship between activity and temperature.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Szasz G,Gruber W,Bernt Esubject
Has Abstractpub_date
1976-05-01 00:00:00pages
650-6issue
5eissn
0009-9147issn
1530-8561journal_volume
22pub_type
杂志文章abstract：BACKGROUND:The goal of this study was to establish a plasma microRNA profile by use of next-generation sequencing that could aid in assessment of patient prognosis in nasopharyngeal carcinoma (NPC). METHODS:Two panels of NPC patients and healthy controls (HCs) were recruited for this study. We used deep sequencing to ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.214213
更新日期：2014-05-01 00:00:00
abstract：BACKGROUND:PCR-based mutation detection is prone to methodological errors, e.g., in restriction length fragment polymorphism (RFLP) and allele-specific amplification (ASA), false PCR results may occur because of technical faults or atypical new mutations. METHODS:We investigated the ability of a genotyping assay based...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
abstract：:We describe a procedure by which surfactant/albumin ratios in bronchoalveolar fluid (BALF) may be quantified with the Abbott Laboratories TDx fluorescence polarization analyzer and fetal lung maturity reagents. Adding albumin to BALF samples shifted the surfactant/albumin ratios to within the analytical range of the m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-07-01 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：: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：:This procedure for routine quantification of albumin in urine is based on the dye-binding properties of albumin with bromphenol blue. The absorbance of 100 microL of urine mixed with 3 mL of color reagent is measured against blank reagent at 610 nm after 30 s. Results vary linearly with albumin concentration up to 6 g...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-02-01 00:00:00
abstract：BACKGROUND:There have been no large-scale analyses of resource utilization comparing the overall costs to treat pediatric patients vs adult patients. Likewise, there have been no studies evaluating the costs of the various components of hospitalization (e.g., accommodation, laboratory, radiology, and drugs) among adult...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：BACKGROUND:The majority of patients with chronic kidney disease are diagnosed and monitored in primary care. Glomerular filtration rate (GFR) is a key marker of renal function, but direct measurement is invasive; in routine practice, equations are used for estimated GFR (eGFR) from serum creatinine. We systematically a...
journal_title：Clinical chemistry
pub_type： 杂志文章,meta分析
doi：10.1373/clinchem.2017.276683
更新日期：2018-03-01 00:00:00
abstract：:Creatine kinase (CK) isoenzymes MM, MB, and BB are located primarily in the cell cytosol, and increased CKMB in plasma is the hallmark of myocardial infarction. However, whether CK is released with reversible ischemic injury remains controversial. Here, we assessed plasma CK activity--cytosolic and mitochondrial CK--i...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-03-01 00:00:00
abstract：BACKGROUND:The antiphospholipid syndrome (APS) is an important cause of acquired thromboembolic complications and pregnancy morbidity. Its diagnosis is based on clinical and laboratory criteria, defined by strict guidelines. The original clinical and laboratory criteria for the identification of APS patients were publi...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2009.133678
更新日期：2010-06-01 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：:We describe a simple method in which a water-soluble mixture of triocatanoin and a surfactant, "Triton X-114," are used in preparing solutions of triglycerides (triacylglycerols) in either human serum, solutions of albumin, or water. Analytical recovery added triglyceride was quantitative by two methods. The addition ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-08-01 00:00:00
abstract：:We describe a modified tantalum ribbon atomic absorption procedure for determining lead in undiluted whole blood. An instrumentation Laboratory (I.L.) Model 151 atomic absorption spectrophotometer equipped with an I.L. Model 355 Flameless Sampler was used. The Flameless Sampler was slightly modified to include three-c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-07-01 00:00:00
abstract：BACKGROUND:An abnormal IgLkappa:IgLlambda ratio has long been used as a clinical criterion for non-Hodgkin B-cell lymphomas. As a first step toward a quantitative real-time PCR-based multimarker diagnostic analysis of lymphomas, we have developed a method for determination of IgLkappa:IgLlambda ratio in clinical sample...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/49.1.51
更新日期：2003-01-01 00:00:00
abstract：:We produced and characterized several monoclonal antibodies directed toward human plasma apolipoprotein A-I. Two of them, A-I-12 and A-I-57, individually precipitated purified or native high-density lipoprotein in agarose gel by double immunodiffusion. Because radial immunodiffusion performed with a single monoclonal ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-12-01 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: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：:We combined the amplification refractory mutation system (ARMS) and fluorescence polarization (FP) to give a homogeneous genomic DNA genotype analysis method. Oligonucleotide probes labeled with the fluorescein dyes fluorescein isothiocyanate and 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein and the rhodamine dye 6-c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-08-01 00:00:00
abstract：:Estimation of plasma catecholamine concentrations by "high-performance" liquid chromatography, although increasingly used, still presents difficulties. We describe a method for clean-up of plasma samples on cation-exchange resin before they are extracted with alumina. This procedure eliminates many of the interfering ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-07-01 00:00:00
abstract：BACKGROUND:The use of nonstandardized N-terminal pro-B-type natriuretic peptide (NT-proBNP) assays can contribute to the misdiagnosis of heart failure (HF). Moreover, there is yet to be established a common consensus regarding the circulating forms of NT-proBNP being used in current assays. We aimed to characterize and...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2012.200204
更新日期：2013-10-01 00:00:00
abstract：BACKGROUND:Coffee consumption has been associated with several risk factors for coronary heart disease, including increased cholesterol, increased blood pressure, and increased plasma total homocysteine (tHcy). tHcy is determined by several B-vitamins. However, reports about the association between coffee intake and B-...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.103465
更新日期：2008-09-01 00:00:00
abstract：:In this liquid-chromatographic method for the determination of bromide in human serum, an important and unique feature is pre-analysis ultrafiltration of the sample, which effectively removes proteins. The chromatographic system consists of an anion-exchange column (Whatman Partisil SAX 10-micron particles), an isocra...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
abstract：BACKGROUND:Measurement of postimmunization antibody response to pneumococcal capsular polysaccharide (caps-PS) is the standard method to identify deficiency of antipolysaccharide antibody production. However, no standardized criteria have been defined for classification of patients into responders or nonresponders to c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.080051
更新日期：2007-03-01 00:00:00
abstract：:We measured the free amino acids in plasma of 58 patients with HIV infection and in six persons in the risk group. The HIV+ patients had significantly increased concentrations of arginine, phenylalanine, and glutamate in comparison with both age- and sex-matched controls and the members of the risk group. Glutamate co...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-09-01 00:00:00
abstract：:We describe a rapid and simple insulin RIA in which proinsulin and conversion intermediates do not interfere. Three monoclonal antibodies (S1, S2, and S53) were selected for their specificity (directed, respectively, against the B10 region, the junction between A chain and C-peptide, and the junction between B chain a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-07-01 00:00:00
abstract：:We describe a sensitive method for the determination of vanadium in biological substances by atomic absorption spectroscopy. By using background correction and pyrolytically coated graphite tubes with flameless apparatus, this vanadium assay has a sensitivity of 65 pg and a detection limit of 30 pg, approximately sixf...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 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：:gamma-Aminobutyric acid (GABA), an inhibitory neurotransmitter that serves about one-third of brain neurons, is involved in the development of depression and in the treatment of depression and mania with pharmacological therapy. Brain activity of GABA may be conveniently measured in plasma, and changes in plasma conce...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1994-02-01 00:00:00
abstract：:We describe a gas--liquid-chromatographic method for determining the concentration of amantadine hydrochloride in urine with beta-phenylethylamine as internal standard. The urine sample is made alkaline and extracted with 0.5 mL of chloroform. After centrifugation the aqueous layer is aspirated, and an aliquot of the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-02-01 00:00:00
abstract：BACKGROUND:Microalbuminuria (MA) is recognized as an important risk factor for cardiovascular and renal complications in diabetes. We sought to evaluate how screening for MA is conducted and how urine albumin (UA) results are interpreted in primary care internationally. METHODS:General practitioners (GPs) received a c...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.100917
更新日期：2008-10-01 00:00:00
