Abstract：
:We studied the effect of lyophilization of serum pools on the determination of cholesterol with the enzymatic methods used in five automated analyzers: SMAC (Technicon), the RA-1000 (Technicon), the aca (Du Pont), the TDx (Abbott), and the Ektachem 700P (Kodak). We prepared two serum pools: pool A (2.2 g/L) and pool B (1.9 g/L). We separated each pool into three groups for treatment by lyophilizing or freezing at -20 and -70 degrees C. We determined cholesterol by the above methods at regular intervals during the next 270 days. For all methods, the measured concentration of cholesterol was less for the lyophilized serum than for frozen (P less than 0.007 by the paired-sample t-test). After adjusting for the dilutional effects of reconstitution, the decrease in original value was 0.7% for the SMAC, 1.7% for the RA-1000, 5.7% for the Ektachem, 9.4% for the TDx, and 14.3% for the aca. Lyophilization of cholesterol standards or serum samples may hamper the effective standardization of enzymatic methods and may be a source of apparent inaccuracy (bias) among enzymatic methods.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Kroll MH,Chesler R,Elin RJsubject
Has Abstractpub_date
1989-07-01 00:00:00pages
1523-6issue
7eissn
0009-9147issn
1530-8561journal_volume
35pub_type
杂志文章abstract：:We developed a simple method for the analysis of bismuth (Bi) in biological tissue, using wet digestion for sample pretreatment. Bi was determined by electrothermal atomic absorption spectrometry with platinum as a matrix modifier to decrease the volatility of Bi. The furnace program included a gas stop for sensitivit...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-05-01 00:00:00
abstract：BACKGROUND:Vascular smooth muscle cells (SMCs) migrate from the arterial media to the intima in the progression of atherosclerosis, and dysfunction of SMCs leads to enhanced atherogenesis. A soluble form of the LDL receptor relative with 11 ligand-binding repeats (sLR11) is produced by the intimal SMCs, and the circula...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.127027
更新日期：2009-10-01 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：:Concentrations of free thyroxin (T4) and free triiodothyronine (T3) were measured in sera from pregnant women, in subjects with congenitally increased or decreased thyroxin-binding globulin (TBG), and in euthyroid controls. Measured free hormone concentrations were compared with calculated values for free hormone deri...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-08-01 00:00:00
abstract：BACKGROUND:Mass spectrometric assays could potentially replace protein immunoassays in many applications. Previous studies have demonstrated the utility of liquid chromatography-multiple-reaction monitoring-mass spectrometry (LC-MRM/MS) for the quantification of proteins in biological samples, and many examples of the ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.173856
更新日期：2012-04-01 00:00:00
abstract：:We have developed a fully enzymatic method to measure 1,5 anhydro-D-glucitol (1,5-AG) in serum through use of pyranose oxidase (PROD: EC 1.1.3.10), glucokinase (EC 2.7.1.2), and an ATP-regenerating system. In a previous report (Clin Chem 1989;35:2039-43) the glucose interfering with the measurement of 1,5-AG was remov...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-11-01 00:00:00
abstract：BACKGROUND:Growth differentiation factor 15 (GDF15), a stress-responsive cytokine produced in cardiovascular cells under conditions of inflammation and oxidative stress, is emerging as an important prognostic marker in individuals with and without existing cardiovascular disease (CVD). We therefore examined the clinica...
journal_title：Clinical chemistry
pub_type： 杂志文章,meta分析
doi：10.1373/clinchem.2012.190322
更新日期：2012-11-01 00:00:00
abstract：:Recent evidence indicates that high-density lipoprotein triglyceride (HDL-Tg) may be a predictor of coronary artery disease. We examined three methods for HDL-Tg measurement, comparing results obtained by measurement of Tg in the supernate after heparin-manganese chloride (heparin-Mn) precipitation of EDTA-treated pla...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-10-01 00:00:00
abstract：BACKGROUND:Intraventricular hemorrhage (IVH) is a major cause of neurologic disabilities in preterm newborns. We evaluated the use of plasma activin A concentrations to predict the development of perinatal IVH. METHODS:We measured nucleated erythrocyte (NRBC) counts, plasma activin A, hypoxanthine (Hyp), and xanthine ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.065979
更新日期：2006-08-01 00:00:00
abstract：BACKGROUND:First introduced in 2006, recombinase polymerase amplification (RPA) has stirred great interest, as evidenced by 75 publications as of October 2015, with 56 of them just in the last 2 years. The widespread adoption of this isothermal molecular tool in many diagnostic fields represents an affordable (approxim...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2015.245829
更新日期：2016-07-01 00:00:00
abstract：:This enzyme immunoassay detects adenosine deaminase binding protein (ABP), a glycoprotein that is shed from the brush border of the proximal tubule in kidney damage. Two monoclonal antibodies, URO-4 and URO-4a, each react with different epitopes on ABP and are used as the "sandwich" pair of antibodies. A linear standa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-05-01 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 review the present knowledge of telomeres and telomerase with special attention to their role in cell proliferation, cellular senescence, and human aging. We summarize the functional aspects of telomerase in cancer, as well as its role as a useful diagnostic and prognostic tumor marker, and discuss possible approac...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1997-05-01 00:00:00
abstract：:Advanced glycosylation end products (AGEs) are thought to play an important role in the development of diabetic complications. Oxidative reactions are essential for the formation of some AGEs, termed glycoxidation products. Increased concentrations of pentosidine, one of such products, are found in tissue and serum in...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：:A new radiometric assay specific for creatine kinase isoenzyme MB was evaluated with respect to its precision and agreement with a conventional electrophoretic CK-MB assay for the diagnosis of myocardial infarction. The reference interval we find for serum CK-MB in healthy subjects is 0--30 micrograms/L. The coefficie...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-06-01 00:00:00
abstract：:Urinary excretion of orally administered lactulose is used as an index of intestinal permeability. We have developed a simple thin-layer chromatographic technique for measuring lactulose in urine, using silica gel 60 plates and a propanol-borate solvent system. Lactulose concentrations as low as 62.5 mg/L can be detec...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-07-01 00:00:00
abstract：:Genetic engineering of beta-galactosidase (EC 3.2.1.23) has led to the development of a new homogeneous assay system, CEDIA. The Z gene of the lac operon of Escherichia coli encodes a large enzymatically inactive polypeptide that spontaneously aggregates and folds to form active beta-galactosidase. Using recombinant D...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-09-01 00:00:00
abstract：:A 56-year-old Samoan man with a documented history of hypertension, who presented with atrial fibrillation and hypotension, quickly developed renal failure with a serum urea nitrogen of 1.370 g/L and a serum creatinine of 92 mg/L. After hydration of the patient, the creatinine value became normal in two days, the urea...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-11-01 00:00:00
abstract：:Currently, we can make the following generalizations about the major long-term complications of diabetes. First, they occur commonly after 10 to 15 years of diabetes. Second, the complications of renal and retinal disease, but not of atherogenic and neurological disease, appear to be related to the severity of hypergl...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,评审
doi：
更新日期：1986-10-01 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：:With the ultramicroanalytical system described here we can measure glucose in 1 microL of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops. The reflectance of these spots is measured with a reflectance digital matrix photome...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-12-01 00:00:00
abstract：:We compared three current methods (immunoinhibition, "Isomune-CK" immunoprecipitation, and the Tandem-E CKMB II immunoenzymometric assay) for determination of creatine kinase (CK; EC 2.7.3.2) isoenzyme MB in serum. Although results inter-correlated well, the immunoinhibition assay gave higher activity values. Atypical...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：:We describe a rapid method for determining cholesterol sulfate in plasma and erythrocytes. After its single-step isolation by means of anion-exchange chromatography cholesterol sulfate is hydrolyzed, trimethylsilylated, and determined by gas chromatography with flame ionization detection. 5 beta-Cholestan-3 alpha-ol s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-07-01 00:00:00
abstract：:A radioimmunoassay for barbiturates is shown to be equally sensitive to phenobarbital and its major urinary metabolite, p-hydroxyphenobarbital, in serum and urine. Interference by the metabolite can be essentially eliminated by selectively extracting phenobarbital into chloroform. The extraction efficiency of the meth...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-05-01 00:00:00
abstract：:I evaluated use of the fluorescence polarization technique to measure neocarzinostatin, a proteinaceous antitumor antibiotic, and its antibody, in serum. The antigen (neocarzinostatin), labeled with fluorescein isothiocyanate, was allowed to interact with its antibody in a cuvet, in the instrument, yielding an increas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-12-01 00:00:00
abstract：:We tested a new amylase reagent involving chromogenic substrates (Pantrak, Calbiochem-Behring) for precision, dynamic range, and susceptibility to potential interferences. Two p-nitrophenyl-alpha-maltaosides are used as substrates, which amylase cleaves to shorter-chain p-nitrophenyl maltaosides, the latter then yield...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
abstract：:Mycophenolate mofetil, the prodrug form of the immunosuppressive agent mycophenolic acid (MPA), is currently in clinical trials evaluating its effectiveness in transplant recipients. In this study, we validated an ultrafiltration system for the reliable measurement of free MPA. Using this technique, we evaluated facto...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-07-01 00:00:00
abstract：:Macromolecular aspartate aminotransferase was found in the serum of an apparently healthy patient. This complex was composed of aspartate aminotransferase (AST; EC 2.6.1.1) and immunoglobulin. Electrophoresis of the patient's serum showed an abnormal band migrating between mitochondrial (m) and cytosolic (s) AST. The ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-07-01 00:00:00
abstract：:Five genetic defects have been established as risk factors for venous thrombosis. Three are protein C, protein S, and antithrombin deficiencies, defects in the anticoagulant pathways of blood coagulation. Together they can be found in approximately 15% of families with inherited thrombophilia. Their laboratory diagnos...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1997-09-01 00:00:00
abstract：:We present a unified approach to the use of linear models and matrix least squares with the intention of providing a better understanding of the techniques themselves and of the statistics that arise from these techniques as they are used in clinical chemistry. Emphasis is placed on the importance of appropriate exper...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-06-01 00:00:00
