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 methanol extract is evaporated, the residue dissolved in a 93/7 (by volume) mixture of potassium phosphate buffer (20 mmol/L, pH 3.8) and acetonitrile, and an aliquot of this solution is chromatographed. We used a mu-Bondapak C-18 column with the above-mentioned buffer system as mobile phase, a flow rate of 2.0 mL/min, and a column temperature of 40 degrees C. Ritalinic acid and internal standard are detected by their absorbance at 192 nm and quantitated by measuring peak heights. The procedure allows for the reliable analysis for ritalinic acid in serum at concentrations greater than 50 microgram/L. Analytical recoveries were greater than 73% and the method affords good day-to-day precision (CV, less than 12%).
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Soldin SJ,Hill BM,Cahn YP,Swanson JM,Hill JGsubject
Has Abstractpub_date
1979-01-01 00:00:00pages
51-4issue
1eissn
0009-9147issn
1530-8561journal_volume
25pub_type
杂志文章abstract：BACKGROUND:The determination of cellular beta-galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell-based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for beta-ga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.115873
更新日期：2009-03-01 00:00:00
abstract：:We describe a procedure based on equilibrium dialysis that allows the simultaneous determination of free testosterone and testosterone bound to non-sex-hormone-binding globulin (non-SHBG) in plasma. After saturating SHBG with 5 alpha-dihydrotestosterone (DHT) according to a technique recently described, the percentage...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-06-01 00:00:00
abstract：:Using automated measurements of kappa and lambda light chains and IgG, IgA, and IgM, we assessed the utility of the kappa/lambda ratio and the heavy chain/light chain ratio in characterizing monoclonal immunoglobulins previously identified by sensitive electrophoresis on agarose gel and typed by immunofixation or immu...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:We evaluated the technical performance of the Ciba Corning ACS:180 automated immunoassay system for the following analytes: thyroid-stimulating hormone, free thyroxine, luteinizing hormone, follicle-stimulating hormone, prolactin, human chorionic gonadotropin, carcino-embryonic antigen, and prostate-specific antigen. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-03-01 00:00:00
abstract：:A micro version of a nuclear binding assay to assess the biological activity of receptors for steroid hormones was developed for application to small (needle) biopsies of human tumors for the purpose of predicting responses to steroid therapy. This easier assay requires 10-fold less tissue than the original nuclear bi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-02-01 00:00:00
abstract：BACKGROUND:In recent years, there have been significant advances in the development of enzyme replacement and other therapies for lysosomal storage disorders (LSDs). Early diagnosis, before the onset of irreversible pathology, has been demonstrated to be critical for maximum efficacy of current and proposed therapies. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2000-09-01 00:00:00
abstract：BACKGROUND:Small RNAs are key players in the regulation of gene expression and differentiation. However, many different classes of small RNAs (sRNAs) have been described with distinct biogenesis pathways and, as a result, with different biochemical properties. To analyze sRNAs by deep sequencing, complementary DNA synt...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2019.305045
更新日期：2019-12-01 00:00:00
abstract：:We determined fluoxetine (Prozac) and its major metabolite norfluoxetine in plasma by liquid chromatography with fluorescence detection. After liquid-liquid extraction from 1 mL of plasma, the extract was derivatized at room temperature with dansyl chloride, and the highly fluorescent derivatives were chromatographed ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-09-01 00:00:00
abstract：:We measured serum protein and calcium concentrations in 2340 individuals between 10 and 96 years of age from 900 families chosen by probability methods to give a representative population. These values were used to calculate an index, based on a regression analysis of serum protein on calcium, which was then treated a...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-10-01 00:00:00
abstract：:Unsaturated cobalamin-binding capacity in plasma (P-UBBC) is determined by use of a silica gel (QUSO G32) to separate haptocorrin (P-ApoHC) and transcobalamin (P-ApoTC). The method is sensitive and precise: detection limit 13 pmol/L, interassay coefficients of variation 3% for P-UBBC (mean = 1080 pmol/L), 4% for P-Apo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-07-01 00:00:00
abstract：:We evaluated the performance of two homogeneous assays for quantifying HDL cholesterol (HDL-C) and compared them with the phosphotungstic acid (PTA)/ MgCl2 assay. Both homogeneous HDL-C assays were precise, having a within-run CV of < 1.20% and a between-run CV of < 4.07%. The HDL-C values (y) measured by the two homo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-06-01 00:00:00
abstract：:A new instrument has been developed that is similar in design and concept to the GeMSAEC centrifugal analyzer (Oak Ridge National Laboratory) except that electrochemical detection is used rather than optical detection. The present version has eight channels, each with its own detector. Problems of speed control and sa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-09-01 00:00:00
abstract：:Four routine assays commonly used for monitoring plasma methotrexate (MTX) during high-dose therapy were validated by HPLC as the comparison method. MTX and its main metabolite, 7-hydroxymethotrexate (7-OHMTX), were analyzed by HPLC with postcolumn derivatization and fluorometric detection. About 200 clinical plasma s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1996-01-01 00:00:00
abstract：:Detection of intracellular antigens by flow cytometry requires effective fixation and permeabilization of the cell membrane. This study compares three fixation/permeabilization techniques: two commercial chemical reagents, the ORTHOPermeaFix (OPF) and the FIX&PERM Cell Permeabilization Kit (F&P), and a novel method ba...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-11-01 00:00:00
abstract：:Single-spin density-gradient ultracentrifugation (DUC) has proven to be a reproducible method for detection of low-density-lipoprotein (LDL) heterogeneity. Recently another method has been described for this: gradient gel electrophoresis (GGE) of serum, a method that might be more suitable for screening. To gain insig...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-06-01 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：BACKGROUND:In this study we demonstrate the technical application of flow cytometry and cell sorting combined with gene-rearrangement clonality profiling to detect and confirm minimal disease in 2 leukemia and 2 lymphoma cases. METHODS:Specimens with low percentages (0.05%-5%) of abnormal lymphoid populations were ide...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.061259
更新日期：2006-03-01 00:00:00
abstract：BACKGROUND:Standardization of clinical measurements of C-reactive protein (CRP) is based on the availability of reference materials. The serum protein reference material ERM-DA470 was used as a calibrant for various commercially available immunoassays but has now been exhausted. The recently released ERM-DA470k/IFCC wa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.147124
更新日期：2010-09-01 00:00:00
abstract：:We report a procedure for determining fecal long-chain fatty acids (LCFA), triglycerides, and cholesterol after detergent extraction with 10 mL/L Triton X-100, 6 mL/L Brij 30, and 0.1 mol/L HCl in isotonic saline by enzymatic analysis of the extraction supernates. Mean recoveries of calibrators ranged from 105% to 117...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-12-01 00:00:00
abstract：:A triclonal gammopathy is an immunoglobulin abnormality in which three discrete monoclonal subpopulations of immunoglobulin molecules are present in a patient's serum. Monoclonal and biclonal gammopathies have been studied extensively, but relatively little is known about the much rarer triclonal gammopathies. The cas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：:Gel filtration of serum by use of dextran bisacrylamide beads ("Sephacryl S-200," fractionation range: 5000-250 000 daltons), separates the serum proteins into three distinct peaks. We used an eluent containing (per liter) 140 mmol of sodium, 1.10 mmol of calcium, 0.50 mmol of magnesium, and 10 mmol of 2-([2-hydroxy-1...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-12-01 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：BACKGROUND:Unpredictable efficacy and toxicity are hallmarks of most anticancer therapies. Predictive markers are factors that are associated with response or resistance to a particular therapy. METHODS:The English literature relating to predictive markers in oncology was reviewed. Particular attention was paid to met...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2004.046227
更新日期：2005-03-01 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：:A potential genetic marker for hypertriglyceridemia and coronary disease, an apolipoprotein-CIII gene allele displaying a single nucleotide substitution, was found in 71% of Arabs with primary hypertriglyceridemia. Over 96% of the unrelated adults possessing this allele showed hypertriglyceridemia. The same allele was...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-02-01 00:00:00
abstract：BACKGROUND:The fibroblast growth factor (FGF) and FGF receptor (FGFR) axis plays a critical role in tumorigenesis, but little is known of its influence in ovarian cancer. We sought to determine the association of genetic variants in the FGF pathway with risk, therapeutic response, and survival of patients with ovarian ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2013.211490
更新日期：2014-01-01 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：:Using "high performance" liquid chromatography, we studied non-protein-bound fractions and total concentrations of 18 solutes accumulating in sera from a group of 12 patients who were undergoing chronic ambulatory peritoneal dialysis (CAPD) and in predialysis sera from a group of 15 hemodialysis (HD) patients. We moni...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
abstract：BACKGROUND:Recent use of Bacillus anthracis spores as a bioweapon has highlighted the need for a continuous monitoring system. Current monitoring systems rely on antibody-derived probes, which are not hardy enough to withstand long-term use under extreme conditions. We describe new, phage-derived probes that can be use...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.038018
更新日期：2004-10-01 00:00:00
abstract：BACKGROUND:Biochemical markers of bone turnover can provide prognostic information about the risk of osteoporotic fracture and are useful tools for monitoring efficacy of antiresorptive therapy. A serum-based automated assay may be of better clinical value than urinary markers because of lower imprecision and day-to-da...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-04-01 00:00:00
