bluuebunny/crossref_metadata_2025_split huggingface dataset:
Buffer Composition in Paper Electrophoresis
Authors: Laurell C B , Laurell S , Skoog Nancy 
Published: January 2020

Abstract
An apparatus is described for paper electrophoresis according to the moist-chamber principle. A simple method for quantitative evaluation of the different electrophoretic fractions is presented together with the limits for the normal variation of the different serum fractions.
The influence of the composition of the buffer on the separation of the proteins is stressed.
Addition of small amounts of calcium ions results in a separation of the β-fraction into two distinct fractions, β1 and β2Ca. The mobility of β-lipoproteins is decreased in the presence of calcium. The phenomenon was confirmed with the aid of moving-boundary electrophoresis. The refractive contribution of the lipids in the β-lipoproteins in moving-boundary electrophoresis is shown. The mobility of the main β-component containing carbohydrate and of the transferrin is not changed by calciumion.
Vanadium Concentration of Urine
Authors: Rockhold W T , Talvitie N A 
Published: January 2020

Abstract
A rapid, convenient test for the estimation of small amounts of vanadium in urine is described. The method is based on the catalytic effect of vanadium on the oxidation of N, N-diethyl-p-phenylenediamine by potassium chlorate. Only 1 ml. of urine is required and the test is sensitive to quantities of vanadium as low as 0.01 µg. per ml. of urine. Semiquantitative analyses can be made over a range of 0-1 µg. of vanadium per ml. of urine. The test is designed for application in rapid clinical analyses on small amounts of urine to determine possible vanadium absorption and is suggested for use as a screening test to determine on-the-job exposure of workers to vanadium compounds in excess of the suggested threshold limit value. Data showing the application of the test in several species are given.
New Biuret Reagent for the Determination of Proteins in Cerebrospinal Fluid
Authors: Rosenthal Harold L , Cundiff Helen I 
Published: January 2020

Abstract
A new biuret reagent is described which contains disodium ethylen diamine tetraacetate as the copper stabilizing agent. The reagent effectively prevents the formation of cloudiness in determinations of cerebrospinal fluid due, in part, to the precipitation of calcium in alkaline solution. Results obtained with the new reagent compare favorably with those obtained by Kjeldahls analysis.
Quantitative Cephalin-Cholesterol Flocculation Test for Liver Function
Authors: Kibrick Andre C 
Published: January 2020

Abstract
The quantitative cephalin-cholesterol flocculation test of the author has been modified to give values in percentage of the absorption of the control tube with saline. This simple test which involves only a measurement of absorption in the centrifuged supernatant fluid may be used with any photoelectric colorimeter. Data are presented to show that in 29 of 35 serums giving values above 40 per cent the patients have other evidence of liver disease, while in only 5 out of 45 serums giving values below 40 per cent, the patients have possible liver damage. The same consistency in the results on 296 other patients is reported.
Affinity Characteristics of Amylase-Binding Substance(s) Prepared from Macroamylase Complexes
Authors: Fridhandler L , Berk J Edward , Wong Deborah 
Published: January 2020

Abstract
Partially purified macroamylase complexes, subjected to chromatography at pH 3.4, were partly or completely dissociated in each of the 30 sera so studied. The protein fractions contained variable quantities of residual undissociated macroamylase. They also contained binding substance(s), as evidenced by ability to bind added amylase. Pancreatic and salivary amylase were separately mixed with each preparation of binding substance(s) and chromatographed. Binding affinity, measured by the activity of newly formed macroamylase, varied considerably. Most of the binding substances bound considerably more salivary than pancreatic amylase; none showed markedly greater affinity toward pancreatic than toward salivary amylase. By and large, there appeared to be an association between the isoamylase pattern of the amylase released from the macroamylase complexes at pH 3.4 and the relative binding affinities of the binding substances toward pancreatic and salivary amylases.
Nature of Isoamylases Released, by Acidification, from Macroamylase Complexes
Authors: Fridhandler L , Berk J Edward , Montgomery K 
Published: January 2020

Abstract
We describe observations of the isoamylase nature of the amylase released by acid from partially purified macroamylase complexes that are dissociable under acid conditions. The released isoamylases displayed the chromatographic characteristics previously found in the pancreatic type (P-type) and salivary type (S-type) of amylases in human serum and urine. The proportions of S- and P-types released from 30 macroamylase complexes varied over a much wider range than those proportions found in 27 normal sera. Of particular note was the relatively large number of cases in which there was a marked preponderance of S-type in the released amylase. These data testify further to the varied nature of cases of macroamylasemia, and contribute additionally to their systematic classification.
Rapid Two-Dimensional Immunoelectrophoresis of Human Serum Proteins
Authors: Wright G L , Pollack Louis , Roberts D B 
Published: January 2020

Abstract
We describe two versions of a two-dimensional immunoelectrophoretic system and illustrate their use for separating and estimating human serum proteins. Each is sensitive, rapid, and simple to perform, and requires no special apparatus and only 0.1-0.6 ml of antiserum. Both procedures appear to be potentially useful in the clinical laboratory. Time required to obtain a stained pattern varies from 4.5 to 7 h, depending on the intended purpose and sensitivity (number of possible precipitin peaks) desired. With the faster method ("rapid screening") 25 to 35 precipitin peaks are detected. With the slower but more sensitive method 40 to &gt; 50 peaks are detected. The sensitivity of either version is a function of the titer of the polyvalent antiserum to whole human serum. Of the precipitin peaks thus far detected, 35 have been identified.
Direct Determination of Total Serum Phospholipid by X-Ray Fluorescence
Authors: Leyden Donald E , Carr Peter W , Nonidez William K 
Published: January 2020

Abstract
An x-ray fluorescence method for measurement of total serum phospholipid is described. A Folch extract of 1 ml of serum is evaporated and deposited on a paper disc by washing with chloroform. A coefficient of variation of 4% was obtained for samples containing at least 1 micromole of lipid, as phosphorus. The major advantage of the method is its speed (5 min/sample) in comparison to the phosphomolybdenum blue procedure. The method is free of interference from other lipid constituents and phosphorous content can be standardized by comparison with very stable inorganic phosphates.
Systematic Bias between Blood-pH Instruments
Authors: Ladenson Jack H , Smith Carl H , Dietzler David N , Davis J E 
Published: January 2020

Abstract
Measurement of tris(hydroxymethyl)aminomethane buffers and blood samples was used to compare the following commercial pH instruments: Corning Models 160 and 165, Instrumentation Laboratory, Inc. Model 313, and Radiometer Models E5021 and BMS 3MK2. These comparisons uncovered a systematic bias of 0.02 pH units in Instrumentation Laboratory, Inc. electrodes manufactured before April 1973. Other factors found to affect analytical results were the temperature of the saturated KCl salt bridge and reference electrode, the design of the temperature-control system, and the buffer used to standardize the instruments.
Re-evaluation of EDTA-Chelated Biuret Reagent
Authors: Chromý V , Fischer J , Kulhánek V 
Published: January 2020

Abstract
We studied the optimal composition of EDTA-chelated biuret reagent for the determination of protein in serum. A reagent containing 18 mmol of EDTA, 15 mmol of Cu2+, and 1 mol of NaOH per liter exhibits a very low blank but about the same sensitivity as tartrate-chelated reagents. Maximum color intensity is attained within 25 min at room temperature, and adheres to Beer's law up to 120 g of protein per liter.
Formaldehyde Interference with the o-Toluidine Procedure for Glucose
Authors: Bond Lawrence W , Savaria Anita M , McComb Robert B 
Published: January 2020

Abstract
Formaldehyde, in the quantities normally used to preserve uric acid—gluose reference quality-control solutions, interferes with glucose analysis of these solutions by the o-toluidine procedure. This effect is enhanced by the uric acid present and is observed with other aldehydes.
Application of a Vidicon Spectrometer for Simultaneous Flame-Emission Analysis for Sodium and Potassium in Serum
Authors: Cook Thomas E , Milano Michael J , Pardue Harry L 
Published: January 2020

Abstract
We describe a unique new approach to analytical spectroscopy, which makes use of a silicon-target vidicon tube to rapidly and repetitively scan ultraviolet and visible spectra. We discuss the concept and characteristics of the vidicon spectrometer and illustrate its application to simultaneous determination of sodium and potassium in serum by flame photometry. Average values of coefficients of variation for sodium and potassium are 1.1% and 1.7%, respectively. Recoveries of sodium and potassium added to sera were 99.5% and 99.8%, respectively. When the same burner and flame conditions were used with the vidicon spectrometer and a conventional flame photometer, deviations among results were well within ±3 mmol/liter for sodium and 0.2 mmol/liter for potassium. A bias is observed for both elements when results obtained with an air-hydrogen flame are compared with results obtained with an air-propane flame. Our data illustrate that the vidicon spectrometer is a viable tool for both routine applications and basic studies of effects of flame conditions on two or more elements simultaneously.
Feasibility of Recording Clot Lysis with the Thermometric Clot Detector
Authors: Bostick William D , Carr Peter W 
Published: January 2020

Abstract
We investigated the possibility of continuously recording the process of clot lysis with a thermometric clot detector. Experiments in which fibrinolytic activators and inhibitors were used demonstrate that the detection system, without any mechanical modifications, is suitable for monitoring the complete coagulation process from clot formation to the ultimate lysis of the clot itself.
Some Marker Dyes for Locating Steroids Eluted from Sephadex LH-20 Columns
Authors: Drewes Patricia A , Kowalski Adalbert J 
Published: January 2020

Abstract
As a routine internal calibration system, the use of marker dyes is easier, faster, and more reliable for precisely locating steroids separated by column chromatography on Sephadex LH-20 than is the customary method, pre-calibration by radioactivity. Certain azobenzene and azotoluene dyes are suitable for signaling the effluent positions of various steroids of clinical interest. The elution behavior of this group of dyes is described for two nonpolar solvent systems commonly used in steroid chromatography; however, the technique is generally applicable and this group of dyes may be generally useful as visual markers.
Calculations and Correction Factors Used in Determination of Blood pH and Blood Gases
Authors: Burnett Robert W , Noonan Daniel C 
Published: January 2020

Abstract
Measurement of blood pH, po2 and pco2 also involves calculation of two or more derived quantities and correction of the measured values in cases where the body temperature of the patient differs from the temperature of measurement. References to the pertinent calculations and the temperature corrections are scattered through the literature of several medical specialties, and much new information has been gathered in recent years that directly affects these calculations. This review explains each of the derived quantities and correction factors most used in this field and also provides the best available data for the calculations, in a form that can readily be adapted to electronic data processing.
Factors Contributing to Intra-Individual Variation of Serum Constituents: 3. Use of Randomized Duplicate Serum Specimens to Evaluate Sources of Analytical Error
Authors: Bokelund Henning , Winkel Per , Statland Bernard E 
Published: January 2020

Abstract
In study of intra-individual variation of serum constituents, we used analysis of variance to separate biological from analytical variation, the latter being estimated from results for duplicate specimens. However, the replication error term in such a model may grossly overestimate instrumental variability, especially when a significant pre-instrumental error component is present. To separate pre-instrumental and instrumental error, we used the following experimental design: Duplicate serum specimens were obtained from 88 healthy men, the blood being collected at one venipuncture and immediately divided into two portions. The duplicates were randomized and analyzed on one occasion with the "AutoChemist Multi-Channel Analyzer," and pre-instrumental variation was estimated from the results. Instrumental variation was estimated from results for three independent populations with widely different mean analyte concentrations; these samples were analyzed at the same time as the samples just mentioned. Of the 20 serum constituents assayed, sodium, potassium, iron, total lipids, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and total bilirubin showed significant pre-instrumental error components, as evidenced from significant χ2-tests comparing analytical and "duplicate sample" variation. For total serum protein, albumin, total lipids, cholesterol, and alkaline phosphatase, we found a significant difference (by paired t-test) between values for the first and second specimen.
Trace-Element Analysis in Hair: An Evaluation
Authors: Hilderbrand David C , White Dari H 
Published: January 2020

Abstract
The use of hair as an index to the concentration of certain elements in tissues has been evaluated with regard to the effect of prior cosmetic and sample-washing treatments on the results. Untreated rat-hair samples were subjected to selected grooming or cosmetic products and then washed by various commonly cited sample-preparation procedures. The hair samples were then analyzed for Ca, Mg, Cu, and Zn, and the concentrations found were compared to those in untreated samples. The results indicate that the values observed can be greatly altered by typical treatments given to human hair, and that such changes are not corrected by the commonly used sample-wash procedures. Thus, obtainable samples of human hair, including pubic hair, cannot be expected to indicate accurately the concentration of these metals that would otherwise be present. Other elements should be similarly studied before confidence can be placed in the validity of data for them.
Furosemide Concentrations in Serum and Urine, and Its Binding by Serum Proteins as Measured Fluorometrically
Authors: Forrey A W , Kimpel B , Blair A D , Cutler R E 
Published: January 2020

Abstract
We describe a modification of the fluorometric method of Häussler and Hajdú [Arzneim. Forsch. 14, 704 and 709 (1964)] for assay of furosemide in either serum or urine. A 1-ml sample, acidified to pH 2, is extracted with 5 ml of diethyl ether; 4 ml of the ether is back-extracted into 1 ml of phosphate buffer (pH 7.0, 0.1 mol/liter), and finally acidified with 1 ml of dilute HCl (0.6 mol/liter). A procedure for estimating blanks in urine was derived to correct for dilution caused by diuresis. Internal standards are used, and the "effective" extraction ratio is used to correct for the effects of quenching and extraction differences. In equilibrium, 93% of the drug is bound to serum proteins; 65% is tightly bound. Erythrocytes contain less than 5% of the drug. Quantum yield of fluorescence at pH 1 is 0.0496 for furosemide and is 0.0163 for 4-chloro-5-sulfamoylanthranilic acid. Furosemide fluorescence diminishes with increasing pH, while that of 4-chloro-5-sulfamoylanthranilic acid (a degradation product) increases.
Spectrophotometric Determination of Ethchlorvynol in Biologic Specimens
Authors: Wallace Jack E , Hamilton Horace E , Riloff Joel A , Blum Kenneth 
Published: January 2020

Abstract
A sensitive, highly specific spectrophotometric method for quantitative determination of ethchlorvynol in biologic specimens is described. The procedure is based on conversion of ethchlorvynol to a product mixture consisting of two major components that strongly absorb ultraviolet light. Results can be obtained within 45 min of receipt of a specimen.
Use of Charcoal to Concentrate Drugs from Urine before Drug Analysis
Authors: Meola John M , Vanko Michael 
Published: January 2020

Abstract
A simple, efficient method is described for detecting various drugs in urine, such as barbiturates, glutethimide, ethchlorvynol, amphetamines, phenothiazines, quinine, morphine, cocaine and its metabolites, diazepam, chlordiazepoxide. The drugs are adsorbed from urine onto charcoal, selectively eluted with small amounts of ethyl ether or chloroform—isopropanol, separated and identified by thin-layer chromatography. Sequential spraying of the chromatographic plates with conventional reagents (except for fluorescamine, which is used to detect d-amphetamine) makes the drugs visible. The average detection limit for all drugs is 1.0 µg/ml of urine. The procedure is fast, economical, and adaptable to any urine screening program. No emulsions are formed and water washings are not required as with the use of resins. The preliminary charcoal-adsorption step permits excellent thin-layer chromatographic resolution of the drugs, with low background of interfering compounds.
Microsampling for Blood-Lead Analysis
Authors: Bratzel M P , Reed A Jane 
Published: January 2020

Abstract
We detail the technique, procedure, and equipment required to properly obtain a micro-scale capillary (fingerstick) blood specimen for subsequent determination of its lead content. We divide the microsampling procedure into preparation of sampling equipment and subject, the fingerstick, micro blood collection devices, and transport and storage. The concept of a total-system approach to quality control for sampling and analysis is presented. For realistic quality control, the sampling component and the analysis component are inseparable. We describe types and sources of errors encountered. Most of the variability in the total system is associated with sampling.
Determination of Total and Inorganic Mercury in Hair by Flameless Atomic Absorption, and of Methylmercury by Gas Chromatography
Authors: Giovanoli-Jakubczak Teresa , Greenwood Michael R , Smith J Crispin , Clarkson T W 
Published: January 2020

Abstract
A new procedure for alkaline digestion of hair was used for the selective determination of total and inorganic mercury by flameless atomic absorption and the determination of methylmercury by an improved gas-chromatographic procedure. The precision of the measurements by atomic absorption for total, inorganic, and organic mercury (by difference) was 1.9%, 6.5%, and 2.1%, respectively. Recoveries ranged from 98 to 99.4%. The precision of the measurements of methylmercury by gas chromatography was 3.7% and the recovery 95.6%. Individual samples were corrected for recovery by using radiolabeled methylmercury. A high level of correlation (r = .99) was found between methylmercury as measured by gas chromatography and organic mercury as determined by atomic absorption. Contamination of hair by external applications of mercurials was differentiated from mercury deposited in hair from the diet by means of a special washing procedure, which removed selectively the externally absorbed Hg0, Hg2+, and CH3Hg+. The internally deposited mercury was shown to be stable in spite of exposure to various cosmetic and washing treatments.
Radioimmunoassay for Dexamethasone in Plasma
Authors: Hichens Martin , Hogans Alice F 
Published: January 2020

Abstract
We describe a radioimmunoassay for detection of dexamethasone in plasma. Antibodies to dexamethasone hemisuccinate coupled to bovine serum albumin were obtained in rabbits and used for binding of the synthetic steroid. Concentrations of dexamethasone between 0.5 and 40 µg/liter of plasma can be measured with this procedure.
Correlation of the "EMIT" Urine Barbiturate Assay with a Spectrophotometric Serum Barbiturate Assay in Suspected Overdose
Authors: Walberg Clifford B 
Published: January 2020

Abstract
A rapid method for determining the presence of barbiturate in serum has been needed for some time. Presently used methods are all relatively time-consuming. A rapid immunoassay for the detection of barbiturate in urine, the "Enzyme Multiplied Immunoassay Technique" (EMIT), has recently become available. We have compared results of the EMIT urine assay with results of a spectrophotometric assay of serum (203 patients). Our purpose was: (a) to determine whether a negative result would be obtained with the EMIT assay in cases in which barbiturate was not a factor in coma, and (b) to determine whether a positive EMIT result would be obtained when a significant (3 mg/liter) quantity of barbiturate was in fact present in the serum. We conclude that the EMIT urine assay suffices to indicate clinically if barbiturate may be responsible if a patient is comatose. Results for a specimen (i.e., positive or negative) can be obtained in 5-10 min, so time saved by using the EMIT urine assay as a screening technique is significant.
Causes of Increased Plasma Creatine Kinase Activity after Surgery
Authors: Phornphutkul Kannika S , Anuras Sinn , Koff Raymond S , Seeff Leonard B , Mahler Donald L , Zimmerman Hyman J 
Published: January 2020

Abstract
To determine whether drug reactions might play a role in postoperatively increased plasma enzyme activity, we measured creatine kinase (CK), and ornithine carbamoyl transferase (OCT) activities immediately before and on the 1st, 4th, and 8th day after 343 elective surgical procedures performed on 327 patients who had received various drugs pre-operatively. We saw no overt clinical evidence of muscle damage, but plasma CK activity was significantly increased on the first postoperative day. Plasma OCT activity was not significantly altered. We found no relationship between prior drug exposure and in creased CK activity, but the administration of general rather than regional anesthesia and the duration of anesthesia during surgery were closely related to increased CK activity. Halothane or succinylcholine administration during operation was also associated with a significant increase in CK activity in subjects whose pre-operative CK activity was normal. In contrast, subjects with increased pre-operative CK activities did not show this response to halothane or succinylcholine.
Use of Enzyme-Linked Antibodies to Measure Serum Anti-DNA Antibody in Systemic Lupus Erythematosus
Authors: Pesce A J , Mendoza N , Boreisha I , Gaizutis M A , Pollak V E 
Published: January 2020

Abstract
We describe a solid-phase adsorbent enzyme-linked immunoassay for measuring the amount of antibody in serum. The assay consists of adsorbing an excess of DNA to a polystyrene test-tube support, reacting the anti-DNA serum with the coated tube, following with an additional reaction of an anti-human γ-globulin peroxidase enzyme conjugate with the coated tube, and finally developing a colored reaction product by the action of peroxidase on substrate. In principle, the amount of IgG bound to the tube is proportional to the amount of anti-DNA contained in the serum, and the conjugate also reacts proportionally to the amount of human IgG that has reacted. The assay gives data consistent with that expected for serum from patients with systemic lupus erythematosus, and it is possible to titrate the serum for micrograms of DNA antibody. At present the method still has considerable variability, but offers a new approach to measurement of antibody in autoimmune diseases.