Abstract:
:To determine the molar absorptivities of beta-NADH and beta-NAD at 260 nm, we purified the reduced form of the coenzyme by repeated anion-exchange chromatography. A NADH preparation was so obtained for which the 260 nm/340 nm absorbance ratio was 2.265. When calculated with epsilon 340 beta-NADH = 6.22 times 10-3 for beta-NADH at 260 nm and 25 degrees C, a molar absorptivity of 14.1 times 10-3 liter - mol minus 1 - cm minus 1 resulted from this quotient. By use of the lactate dehydrogenase or glycerol-3-phosphate dehydrogenase assay, respectively, and referring to the new absorption coefficient for NADH at 260 nm, the molar absorptivity of beta-NAD at 260 nm and 25 degrees C was established to be 17.4 times 10-3 liter - mol minus 1 - cm minus 1. The values observed are lower than those reported thus far.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Haid E,Lehmann P,Ziegenhorn Jsubject
Has Abstractpub_date
1975-06-01 00:00:00pages
884-7issue
7eissn
0009-9147issn
1530-8561journal_volume
21pub_type
杂志文章abstract:BACKGROUND:The association of changes in oxidative and proinflammatory states with vascular function after diet and exercise intervention among obese children has not been previously explored. METHODS:In this 6-week diet and exercise intervention study in 35 obese children, age 12 to 18 years, we evaluated the relatio...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:10.1373/clinchem.2007.089953
更新日期:2008-01-01 00:00:00
abstract:PURPOSE:To review information on the use of laboratory tests in screening, diagnosis, and monitoring of acute and chronic hepatic injury. DATA SOURCES AND STUDY SELECTION:A MEDLINE search was performed for key words related to hepatic diseases, including acute hepatitis, chronic hepatitis, alcoholic hepatitis, cirrhos...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:2000-12-01 00:00:00
abstract::This highly sensitive method for determination of beta 2-microglobulin (beta 2-m) in human urine or serum is based on direct agglutination by beta 2-m of latex particles on which an antibody against beta 2-m is adsorbed. The agglutination is quantified by counting the remaining unagglutinated particles, or by turbidim...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-06-01 00:00:00
abstract::The precision of estimates of the sensitivity of diagnostic tests is evaluated. "Sensitivity" is defined as the fraction of diseased subjects with test values exceeding the 0.975-fractile of the distribution of control values. An estimate of the sensitivity is subject to sample variation because of variation of both c...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-04-01 00:00:00
abstract::Demonstrable quality of laboratory services entails two parts. First, one needs a quality policy statement, identification of user needs, choice of measurement procedures, reference measurement system to provide traceability, control materials, and proficiency testing with materials having reference-measurement-assign...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1994-07-01 00:00:00
abstract::In the diagnosis of chronic (as opposed to acute) liver diseases, combinations of indicators are needed to improve specificity. Alanine aminopeptidase (AAP; microsomal aminopeptidase, EC 3.4.11.2) activity in serum reportedly is a very sensitive indicator of intrahepatic cholestasis and biliary obstruction; it is also...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-03-01 00:00:00
abstract:BACKGROUND:There are 45 known genetic diseases that impair the lysosomal degradation of macromolecules. The loss of a single lysosomal hydrolase leads to the accumulation of its undegraded substrates in tissues and increases of related glycoconjugates in urine, some of which can be detected by screening of free oligosa...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2012.201053
更新日期:2013-09-01 00:00:00
abstract:BACKGROUND:In 2008, the US Food and Drug Administration (FDA) issued a Guidance for Industry statement formally recognizing (during drug development) the conjoined nature of type 2 diabetes (T2D) and cardiovascular disease (CVD), which has precipitated an urgent need for panels of markers (and means of analysis) that a...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2010.156976
更新日期:2011-05-01 00:00:00
abstract::Lactate dehydrogenase (LD) isoenzymes 1 and 2 in human serum were separated on a column of diethylaminoethyl-Sephadex. Samples layered on mini-columns were eluted with buffered sodium chloride (100, 150, and 200 mmol/liter). Lactate dehydrogenase activity in column effluents was measured by the Wacker method, and thei...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-03-01 00:00:00
abstract::Using different substance concentrations in an aqueous 1.25 mmol/L solution of CaCl2 plus NaCl to a final solution ionic strength of 160 mmol/L, we tested six buffers for their effect on measurements of ionized calcium (Ca2+). Measured Ca2+ decreased with increasing ionic strength and pH. Increasing concentrations of ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-02-01 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::Because of uncertainty as to the molecular weight of transferrin, a previous comparison [Von der Heul et al., Clin. Chim. Acta 38, 347 (1972)] between transferrin content of serum and total iron-binding capacity cannot be definitive. We found a conversion factor for expressing the maximum amount of iron bound by 1 mg ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-07-01 00:00:00
abstract::A sensitive method, inductively coupled plasma atomic emission spectroscopy, is used to measure desferrioxamine in blood plasma. The desferrioxamine is transformed into its iron chelate, ferrioxamine, which is extracted into benzyl alcohol, then re-extracted into HCl (0.5 mol/L), which is used as the sample for the sp...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
abstract:BACKGROUND:Hyperhomocysteinemia (HHcy) has been linked to impaired left ventricular function and clinical class in patients with chronic heart failure. We hypothesized that HHcy stimulates myocardial brain natriuretic peptide (BNP) expression and induces adverse left ventricular remodeling. METHODS:We randomized 50 ra...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2006.077859
更新日期:2007-04-01 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:BACKGROUND:HDL is quantitatively the most important lipoprotein in most species and mechanistic evidence points toward a role for HDL in normal immune function. We tested the hypothesis that concentrations of HDL cholesterol are associated with risk of autoimmune disease. METHODS:From 2 studies of the general populati...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2018.299636
更新日期:2019-05-01 00:00:00
abstract:BACKGROUND:FMR1 full mutations (FMs) (CGG expansion >200) in males mosaic for a normal (<45 CGG) or gray-zone (GZ) (45-54 CGG) allele can be missed with the standard 2-step fragile X syndrome (FXS) testing protocols, largely because the first-line PCR tests showing a normal or GZ allele are not reflexed to the second-l...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.244681
更新日期:2016-02-01 00:00:00
abstract:BACKGROUND:Measurement of plasma renin is important for the clinical assessment of hypertensive patients. The most common methods for measuring plasma renin are the plasma renin activity (PRA) assay and the renin immunoassay. The clinical application of renin inhibitor therapy has thrown into focus the differences in i...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:10.1373/clinchem.2008.118000
更新日期:2009-05-01 00:00:00
abstract:BACKGROUND:The alteration of the bone microenvironment as a consequence of skeletal metastases is poorly understood. The aim of this study was to search for patterns of bone markers in relation to primary tumor type, bone pain, and number of sites involved in patients with bone metastases. METHODS:We studied 323 patie...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract::A competitive solid-phase fluoroenzymeimmunoassay has been developed for rapidly measuring 5 beta-pregnane-3 alpha, 20 alpha-diol-3 alpha-glucuronide (Pd-3G) directly in diluted specimens of pre-breakfast urine. The assay involves use of an antiserum to Pd-3G and enzyme-labeled antigen prepared by chemically linking g...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-02-01 00:00:00
abstract:BACKGROUND:We used a difference in bias approach to evaluate the commutability of 4 frozen serum pools for 8 direct methods for measurement of HDL and LDL cholesterol (HDLC and LDLC). METHODS:Freshly collected nonfrozen sera from 138 diseased and 37 nondiseased patients and 4 frozen pools from the CDC Lipid Standardiz...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2015.240861
更新日期:2015-08-01 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::To correct the results of a radioimmunoassay for beta-thyrotropin (TSH) subunit by eliminating the proportion ascribable to intact TSH, we have devised a method that experimentally reproduces the conditions under which the interference develops. Beta-TSH subunit was assayed in several preparations containing known con...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-05-01 00:00:00
abstract::We describe a novel radioimmunoassay procedure for the direct estimation of aldosterone in unextracted plasma and serum samples, in which interfering binding proteins are digested by Proteinase K (Tritirachium alkaline proteinase, EC 3.4.21.14), a powerful proteolytic enzyme. Heating at 75 degrees C for 15 min inactiv...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-12-01 00:00:00
abstract::We describe a new double-antibody enzyme radioimmunoassay for thyroxin-binding globulin (TBG) in serum. A TBG-beta-D-galactosidase complex was prepared with m-maleimidobenzoyl N-hydroxysuccinimide ester. The mean analytical recovery of TBG added to serum was 99%, sample volume and TBG value were linearly related, and ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1982-12-01 00:00:00
abstract::We have modified the 63Ni radiochemical method of Ho (Anal Biochem 1970;36:105) for determination of free fatty acids (FFA) in plasma. Extracting 1 or 0.1 mL of plasma with Dole's mixture (J Biol Chem 1960;235:2595) and washing the "heptane" layer with two volumes of isopropanol/water/dilute (0.5 mol/L) H2SO4 (25/25/1...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1987-01-01 00:00:00
abstract::Time-resolved fluoroimmunoassay was developed for the detection of synovial-type phospholipase A2 (s-PLA2) in human serum. This solid-phase, sandwich assay uses a polyclonal rabbit antibody raised against synovial-type group II PLA2 produced in Escherichia coli. No cross-reactions were detected between s-PLA2 and PLA2...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract::We describe a "high-performance" liquid-chromatographic assay for measuring ritalinic acid in 300 muL of serum. The procedure includes adsorption of ritalinic acid and internal standard (alpha,alpha-dimethyl-beta-emthylsuccinimide) from serum onto charcoal, from which both compounds are eluted with methanol. The metha...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-01-01 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::To assess the distribution of serum concentrations of the atherogenic lipoprotein(a) [Lp(a)] in an obese population and the possible effects of weight reduction, we determined Lp(a) in 52 white, moderately obese subjects (16 men and 36 women). The subjects were participating in a weight-reduction program of diet, exer...
journal_title:Clinical chemistry
pub_type: 临床试验,杂志文章
doi:
更新日期:1991-07-01 00:00:00