bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toluene-Extractable Lipids of Human Urine, with Characterization of a Native Emulsifer
Authors: Fox I S , Devor A W , Devor K A 
Published: January 2020

Abstract
The lipids extracted by toluene in toluene-preserved urine were collected and characterized by thin-layer and gas-liquid chromatography. The lipids extracted by toluene and the lipids in human lipoproteins are similar. In addition, an emulsion of urine and toluene was obtained; the native emulsifying agent was analytically characterized.
Simultaneous Determination of Trimethadione and Its Metabolite, Dimethadione, by Gas—Liquid Chromatography
Authors: Booker H E , Darcey B 
Published: January 2020

Abstract
A simple gas chromatographic procedure is described for the measurement of trimethadione and its major metabolite, dimethadione, in serum. The method, with which compounds can be determined on a single extraction and injection, is reliable and free from interference caused by other drugs, particularly those that the patient is likely to be taking in combination with trimethadione.
Determination of Proteins in Biological Fluids by Electroimmunodiffusion and Two-Directional Immunoelectrophoresis
Authors: Raisys Vidmantas A , Arvan Dean A 
Published: January 2020

Abstract
We have used electroimmunodiffusion and two-directional immunoelectrophoresis to measure proteins in biological fluids. Electroimmunodiffusion is based on the electrophoresis of antigens in antibody-containing agarose under standardized conditions. Pre-albumin, albumin, α1antitrypsin, α2-macroglobulin, IgG, IgA, IgM, IgD, and other proteins have been determined in our laboratory with a precision of ±5%. The lower limit for quantitation is 5 µg/ml. For immunoglobulin quantitation, treatment of the samples with potassium cyanate (carbamylation) before electrophoresis improves sensitivity and accuracy. Two-directional immunoelectrophoresis is based on electrophoretic separation of proteins in agarose or other high-resolution media followed by electrophoresis at right angles to the first direction, in a gel in which an appropriate antiserum has been incorporated. Qualitative and semiquantitative changes in proteins in abnormal specimens can be assessed. The two techniques combined provide a very sensitive tool for the evaluation of protein changes in biologic fluids. A simple apparatus has been designed in which a number of specimens can be analyzed simultaneously by either method.
Gas Chromatograph—Mass Spectrometer—Computer System for Detection and Identification of Abnormal Metabolic Products in Physiological Fluids
Authors: Hutterer Ferenc , Roboz John , Sarkozi Laszlo , Ruhig Alexander , Bacchin Paolo 
Published: January 2020

Abstract
A gas chromatograph—mass spectrometer—computer system was developed to rapidly separate and identify metabolic products of low molecular weight in microliter quantities of physiological fluids. For sample preparation, the silyl derivative extraction method was used, in which extraction, derivative formation, and concentration are achieved in a single step, and components with widely different chemical structures can be analyzed in a single run. Gas-chromatographic peaks were identified by the computer output of high-resolution mass measurements or low-resolution fragmentation patterns. Application is illustrated by a case of inborn metabolic error. The system appears well suited for screening for metabolic disorders.
Development of a Screening Test for L-Dopa and Its Metabolites in Urine
Authors: Routh J I , Bannow R E 
Published: January 2020

Abstract
A simple screening test, sensitive to o-dihydroxyphenyl groups in the urine, was developed for use in monitoring patients with Parkinson's disease who are treated with L-dopa. Compounds measured by this test include dopa, dopamine, 3,4-dihydroxyphenylacetic acid, epinephrine, and norepinephrine. Parallel quantitative experiments, in which ion-exchange chromatography was used, followed by fluorometry and colorimetry, establish the validity of the strip-test results. The test is designed to be used by physician or patient, as well as by clinical laboratory personnel.
Automated Analysis for Drugs in Urine
Authors: Blackmore D J , Curry A S , Hayes T S , Rutter E R 
Published: January 2020

Abstract
Automated methods are described for extracting drugs from urine and for subsequently detecting them by ultraviolet or visible absorptiometry, or by spectrofluorometry. Standard Technicon AutoAnalyzer equipment has been adapted for use in the extraction processes; and manifolds for barbiturates, morphine, and bases are described. For drugs extracted from urine, the limits of detection were 2.5 , µg/ml for barbiturates and 0.2 µg/ml for morphine, Results are given for processing 204-ml samples of urine per hour for morphine and 10 8-ml samples per hour for barbiturate and basic drug analysis.
Measurement and Distribution of Zinc, Cadmium, and Mercury in Human Kidney Tissue
Authors: Livingston Hugh D 
Published: January 2020

Abstract
Simultaneous analyses of human kidney cortex tissues for zinc, cadmium, and mercury were made by neutron activation combined with either radiochemical separation prior to counting or direct germanium detector gamma spectrometry. For some samples from adults and infants, analyses were made on successive tissue slices from the outer cortex to the inner medulla. Zinc and cadmium show a concentration gradient, with the highest concentrations at the outer medulla. Mercury was preferentially concentrated deeper in the cortex. All three metals, and especially cadmium, are found in higher concentrations in adult than in infant kidneys. A mechanism for the rapid increase in renal cadmium is proposed. The heterogeneous renal distribution of the elements indicates that careful sampling is necessary in any comparative study of their occurrence in human kidney tissue.
Radioimmunoassay of Serum Renin Activity and Digoxin Concentrations, with Use of Polyethylene Glycol to Separate Free and Antibody-Bound Ligand
Authors: Barrett M James , Cohen Patricia S 
Published: January 2020

Abstract
Polyethylene glycol in sodium barbital buffer (25 mmol/liter, pH 8.6) was used to separate free from antibody-bound ligand in the radioimmunoassay of serum digoxin and renin. Polyethylene glycol (final concentration, 150 g/kg of buffer) gave maximum sensitivity in these assays. The length of time between addition of polyethylene glycol and centrifugation of precipitated antibody does not affect sensitivity.
Differentiation of Trypsin-Like Enzymes in Human Plasma
Authors: Gullick Herbert D 
Published: January 2020

Abstract
The arginine amidase and arginine esterase activity of human plasma is compared with that of trypsin, thrombin, plasmin, and kallikrein by using the homologous synthetic amino acid substrates, benzoyl arginine amide (BAA) and benzoyl arginine ethyl ester (BAEE). Hydrolyses of BAA and BAEE in plasma are distinguished by several features: pH optimum, heat stability, storage stability, effect of dilution, surface contact activation, streptokinase activation, inhibition by proteolytic enzyme inhibitor, and range of normal variation. The differential sensitivity of trypsin, thrombin, plasmin, and kallikrein toward these substrates and the similarity in reaction characteristics of plasma-BAA and trypsin-BAA provide evidence that the arginine amidase activity of plasma represents trypsin, while the arginine esterase activity of plasma is nonspecific.
Increased Activity of Some Enzymes in Serum in Cases of Severely Decompensated Diabetes, with and without Ketoacidosis
Authors: Belfiore Francesco , Napoli Elena , Lo Vecchio Luigi 
Published: January 2020

Abstract
In each of 10 highly hyperglycemic decompensated diabetics with ketoacidosis, we found a markedly increased serum activity of two lysosomal hydrolases (N-acetyl-β-glucosaminidase and β-glucuronidase). This was also true to a lesser degree of five diabetics with less severe decompensation and without ketoacidosis. The activity of both enzymes and the degree of hyperglycemia were highly correlated. We think these enzymatic changes result from a process of activation and release of tissue lysosomal enzymes, probably occurring in connection with the increased catabolism present in decompensated diabetes. Nonlysosomal (cytoplasmic or mitochondrial) enzymes were less changed (aspartate and alanine aminotransferases) or normal (aldolase, lactate- and malate dehydrogenase, and creatine kinase). This indicates that tissue damage alone could not account for the increased activity of the two lysosomal hydrolases; it therefore seems primarily to be due to involvement of lysosomes.
Concentrations of Lead in Capillary Blood of Newborns
Authors: Kubasik Norman P , Volosin Michael T 
Published: January 2020

Abstract
Lead concentrations in whole blood have been determined for a random sampling of newborns (age 1-8 days) with the use of a microtechnique involving carbon rod atomization and atomic absorption spectrophotometry. The mean lead concentration of the newborns (13.8 ± 4.5 µg/100 ml of whole blood) significantly differed from that of pediatric populations at low (22.6 ± 6.1) and high lead (32.1 ± 10.4) risk. The concentration of lead in amniotic fluid was less than 20 ng/100 ml of fluid. The significance of the newborn lead values and their role in fetal development remains to be determined.
Direct Potentiometric Determination of Total Ionic Fluoride in Biological Fluids
Authors: Hall Larry L , Smith Frank A , De Lopez Ofelia H , Gardner Dwight E 
Published: January 2020

Abstract
We describe a simple method for measuring fluoride concentration in biological fluids, in which the fluoride ion-specific electrode is used, and which is based on the principle of single known addition. Difficulties associated with variations in pH, temperature, ionic strength, complexation, and nonideal electrode response are thus minimized, and accuracy and precision are maximized. The mean recovery of fluoride added to plasma or to urine was 101.5 or 100.5%, respectively. Analytical variation (coefficient of variation) was 8-10% for plasma and 1.5-4% for urine. The method was applied to 26 sera obtained during hospital pre-admission examinations, and gave a mean ionic fluoride concentration of 1.95 µmol/liter (range, 0.84-2.90 µmol/liter), in reasonable agreement with values reported for other procedures that are based on totally different principles.
Measurement of Serum Ionized Calcium with the Ion-Exchange Electrode
Authors: Subryan V L , Popovtzer M M , Parks S D , Reeve E B 
Published: January 2020

Abstract
We found no differences in pH or ionized calcium concentration of serum from blood either collected into evacuated tubes or collected with syringes and separated under oil. Sera can be stored frozen in 1-ml plastic insulin-type syringes for one to three days without significant changes in pH or ionized calcium concentration, whereas storage under oil with or without re-equilibration with CO2 is associated with significant changes in both. Standards prepared with trypsin and triethanolamine give faster electrode response, and their ionized calcium concentrations remain unchanged for 6 h at room temperature. We suggest a not entirely satisfactory control solution of buffered protein, for use in assessing reproducibility of results.
Simplified Primary Screening Procedure for Detection of Hyperlipidemias in Healthy Individuals
Authors: Berenson Gerald S , Srinivasan S R , Pargaonkar P S , Radhakrishnamurthy B , Dalferes Edward R 
Published: January 2020

Abstract
A simplified primary screening procedure is described for determining serum β- plus pre-β-lipoproteins, which is more rapid and less expensive than cholesterol or triglyceride determinations. This method is based on the ability of β- and pre-β-lipoproteins to form insoluble complexes with heparin in presence of Ca2+. Comparison with analytical ultracentrifugation indicated the accuracy of concentrations determined by the present method. This method was used to screen a group of healthy adults and children and diabetic patients. The results show that measuring serum β- plus pre-β-lipoprotein concentrations may be more useful for screening and detecting subtle abnormalities than is determination of either cholesterol or triglyceride.
Statistics of Patient Test Values: Application to Indirect Normal Range and to Quality Control
Authors: Glick John H 
Published: January 2020

Abstract
The use of patient data for calculation of the indirect normal range and for quality control is investigated. The report deals with an empirical study of the properties of various statistics of patient data, and with the selection of appropriate patient statistics for calculation of the indirect normal range and for quality control. In regard to the indirect normal range, it is shown that the mode of the patient data (calculated as the mid-value in a segment of smallest variance in the rank-ordered set) is a useful statistic for characterizing central tendency of the normal range. For the monitoring of systematic error, the median of the patient data is usually the most sensitive indicator of change.
Determination of Serum Acid Phosphatase Activity: A Performance Evaluation for Clinical Laboratories of Upstate New York
Authors: Copeland William H , Vanderlinde Raymond E 
Published: January 2020

Abstract
Determination of acid phosphatase activity in clinical laboratories in New York State was evaluated. After the target values were established by 12 reference laboratories, sets of test samples were mailed over a two-year period on three occasions to, respectively, 264, 242, and 239 laboratories. Their initial (1968) results revealed problems: definition of normal ranges, interchange of specimens, standardization and quality control, and a need for improved techniques. Almost 5% of laboratories interchanged the initial specimens. Unexpectedly, laboratories using the same method reported a two-fold or greater variation in their "normal range." Although there was some improvement after refresher training sessions, performance was more clearly improved a year later for five of the seven major methods used. Use of the Bessey—Lowry—Brock, Babson—Phillips, and Shinowara—Jones—Reinhart methods resulted in the lowest coefficients of variation.
Instrumental and Procedural Sources of Error in Determination of Bile Pigments in Amniotic Fluid
Authors: Burnett Robert W 
Published: January 2020

Abstract
Although the Liley spectrophotometric estimation of bile pigments in amniotic fluid [Amer. J. Obstet. Gynecol. 82, 1359 ( 1961)] is widely used, the levels of accuracy and precision necessary for clinically meaningful results have not been clarified. This paper delineates some of the important instrumental and procedural sources of error, and how each affects the final value of ΔA455: (a) A limit of error propagation is presented to show that the uncertainty in ΔA455 due to instrumental factors is considerably larger than is commonly appreciated. (b) It is desirable to use a logarithmic baseline estimation, as did Liley, instead of a linear estimation, which can introduce a serious bias. (c) Failure to establish a true zero-absorbance baseline before scanning the specimen can also result in a significant bias in the calculated ΔA455.
Determination of Ionized Calcium in Serum by Use of an Ion-Selective Electrode
Authors: Seamonds Bette , Towfighi Javad , Arvan Dan A 
Published: January 2020

Abstract
Ionized calcium was determined in serum from 84 normal individuals by using a flow-through calcium-selective electrode operated at 37°C. The mean value was 1.08 ± 0.06 (2 SD) mmol/liter. The relationship of serum ionized calcium concentration to other serum constituents was examined. The effects of hyperventilation and food ingestion on ionized calcium were studied. Respiratory alkalosis, induced by hyperventilation, caused a decrease in ionized calcium of 0.05 ± 0.02 (2 SD) mmol/liter per 0.1 unit increase in pH. In contrast, the metabolic alkalosis induced by food ingestion caused a decrease in ionized calcium of 0105 ± 0.025 (2 SD) mmol/liter per 0.1 unit increase in pH.
Interference in Pisano’s Urinary Metanephrine Assay after Use of X-Ray Contrast Media
Authors: Johnson LaVell R , Reese Max , Nelson Don H 
Published: January 2020

Abstract
Certain radiopaque dyes ("Renovist" and "Renografin") contain methylglucamine salts of diatrizoate, which interfere in the Pisano cationexchange method for measuring urinary metanephrine. Methylglucamine is adsorbed to the resin and eluted with the metanephrines. It then consumes the periodate, preventing oxidation of the metanephrines to vanillin and leading to falsely negative results. The methylglucamine can be separated from the metanephrines by adsorbing the metanephrines on QAE Sephadex A-25 acetate at pH 11.2.
Computerized Preparation of Two-Way Analysis of Variance Control Charts for Clinical Chemistry
Authors: Riddick J H , Flora Roger , Van Meter Quentin L 
Published: January 2020

Abstract
A system of quality-control data analysis by computer is described, in which two-way analysis of variance is used for partitioning sources of laboratory error into day-to-day, within-day, betweenpools and additivity variation. The partition for additivity is described in detail as to its advantages and applications. In addition, control charts based on two-way analysis of variance computations are prepared each month by computer. This computer program is designed to operate with the IBM 1800 or 1130 computers or any computer with a Fortran IV compiler. Examples are presented of use of the control charts and of tables of analysis of variance.
Clinical Evaluation of a Modified "Oxford T4-by-Column" Method for Serum Thyroxine
Authors: Lee Marcia , Tietz Norbert W , Martinez Charles J 
Published: January 2020

Abstract
Three commercially available kits for determining serum thyroxine (T4) by column were evaluated. Results with all were less than satisfactory, but a series of changes in the Oxford method resulted in increased reproducibility, substantially improved recovery, and extended linearity of the standard curve. Results compared well with the thyrometabolic status of patients and normal individuals. The 95% confidence limits for 219 "normal" hospital employees were 2.9-6.2 µg/100 ml. The suggested normal range for 241 clinically euthyroid patients is 2.5-6.0 µg/100 ml. The coefficient of correlation between results of the proposed method and of the PBI method was 0.30; for the T4 by the Murphy—Pattee method it was 0.75.
Estimation of the Concentration of Low-Density Lipoprotein Cholesterol in Plasma, Without Use of the Preparative Ultracentrifuge
Authors: Friedewald William T , Levy Robert I , Fredrickson Donald S 
Published: January 2020

Abstract
A method for estimating the cholesterol content of the serum low-density lipoprotein fraction (Sf0-20) is presented. The method involves measurements of fasting plasma total cholesterol, triglyceride, and high-density lipoprotein cholesterol concentrations, none of which requires the use of the preparative ultracentrifuge. Comparison of this suggested procedure with the more direct procedure, in which the ultracentrifuge is used, yielded correlation coefficients of .94 to .99, depending on the patient population compared.
Factors Affecting the Radioimmunoassay of Digoxin
Authors: Cerceo Eugene , Elloso Cipriano A 
Published: January 2020

Abstract
We ascertained which factors critically affect the radioimmunoassay of digoxin. These include: products of hemolysis in blood plasma, excessive amounts of bilirubin in the plasma of jaundiced patients, the age of the tritiated digoxin, the presence of gamma-emitting radioisotopes in the plasma from diagnostic tests, the binding tendency of plasma proteins for digoxin, chemiluminescence associated with the serum (or plasma) of uremic patients, and excessive delay between sample collection and assay of unfrozen samples.
Automated Method for Micro-Scale Determination of Serum Carbon Dioxide
Authors: Sterling R E , Flores O R 
Published: January 2020

Abstract
An accessory attachment for the Beckman DSA-560 is described and the method for its use is presented. This accessory permits the automated microdetermination of serum carbon dioxide at a rate of 80 specimens per hour. The precision of the method is good and the results correlate well with those of other accepted techniques.
Urinary Cystathionine, Catecholamine, and Metabolites in Patients with Neuroblastoma
Authors: Helson L , Fleisher M , Bethune V , Murphy M L , Schwartz M K 
Published: January 2020

Abstract
Urinary excretions of cystathionine, catecholamines, and vanillymandelic acid were compared in 27 patients with neuroblastoma and in nine other patients with non-neurogenic tumors. Eleven of the 27 patients were without clinical evidence of active neuroblastoma at the time of the study and excreted no or relatively small amounts of urinary cystathionine. Thirteen of the remaining 16 patients with progressive neuroblastoma had elevated cystathionine values. Elevated values were also detected in three of nine patients with other tumors. There was no correlation between the excretion of cystathionine and either catecholamines or vanillymandelic acid. The assay of cystathionine in addition to catecholamines and vanillymandelic acid is recommended for the complete biochemical evaluation of patients with neuroblastoma.
Some Technical Aspects of Quantitative Immunoelectrophoresis of Human Serum and Cerebrospinal Fluid
Authors: Fuller Janet M , Keyser J W 
Published: January 2020

Abstract
We describe our experiences with quantitative immunoelectrophoresis, by both the procedure of Clarke and Freeman [Clin. Sci. 35, 403 (1968)] and the small-scale modification of Davies et al. [Ibid. 40, 411 (1971)]. Difficulties encountered, aids in measuring and identifying the peaks, and data on the reproducibility of the two procedures are described. Finally, their applicability to cerebrospinal fluid is briefly discussed.
Rapid Gas Chromatographic Measurement of Plasma Procainamide Concentration
Authors: Atkinson Arthur J , Parker Michele , Strong John 
Published: January 2020

Abstract
A gas-chromatographic method has been developed for measuring procainamide in plasma. This simple analysis can be performed in less than an hour with a standard deviation of less than 8% for concentrations of procainamide in the range that is commonly encountered in clinical practice (1-20 mg/liter).
Rapid Estimation of Fibrinogen in Fibrinolytic and Nonfibrinolytic States
Authors: Rosenberg Arthur A , Peabody Richard A 
Published: January 2020

Abstract
Anticoagulated whole blood is serially diluted in a fibrinolytic inhibitor, then clotted with thrombin after adding calcium chloride. The clotting end point, visualized by addition of saline, is related to the concentration of clottable protein present. Protection of the forming clot against lysis is afforded by the inhibitor, by calcium chloride, and by the brief incubation at room temperature, and enables blood fibrinogen concentration to be readily discernible, even if it is less than 25 mg/100 ml. Fibrinogen in the blood is quickly estimated irrespective of the patient’s clinical status.