bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Immunoglobulins from Patterns of Cellulose Acetate Electrophoresis
Authors: Gault M H , Hsieh S , Elzer E 
Published: January 2020

Abstract
The concentrations of serum immunoglobulins (Ig) G, A, and M were correlated with specific features in the β-γ region of densitometer patterns of serum protein electrophoresis on cellulose acetate membranes; visual analysis of densitometer patterns permitted semiquantitative prediction of values for IgG and IgA. Important immunoglobulin abnormalities, particularly elevations of IgA, were seen in some cases even when normal values were obtained from analyses of electrophoresis by usual densitometer integrator technics; many such instances were detectable by inspection of the densitometer tracing.
Aldolase
Authors: Pinto Patrick V C , Van Dreal Paul A , Kaplan Alex 
Published: January 2020

Abstract
The Sigma and Boehringer reagent kits for measuring aldolase activity by a colorimetric method were examined critically. The original Sibley and Lehninger (1) procedure was more satisfactory than the modifications made by the kit manufacturers. Serum aldolase activity measured by the Sigma procedure and our modification of the Sibley-Lehninger method agreed within a standard deviation of ± 2 IU; values obtained with the Boehringer kit were about 50% low.
Enzyme Content of Casts in Chronic Renal Disease
Authors: Wolf Paul L , Horwitz Jerome P , Pierce James , Small Michael , Ing Todd S 
Published: January 2020

Abstract
An investigation of enzyme content of diseased human kidneys was carried out. A broad spectrum of enzymes was studied histochemically in these kidneys. A surprising finding of the presence of various lysosomal, microsomal, and nuclease enzymes was demonstrated in epithelial casts in the kidneys. In contrast, mitochondrial enzymes were not present in the epithelial casts. This study has demonstrated that epithelial casts still retain certain enzymatic activities and are not enzymatically inert.
Recently, we subjected portions of kidneys removed from patients with chronic renal disease (chronic pyelonephritis and chronic glomerulonephritis) prior to transplantation to a comprehensive enzyme histochemical analysis. We observed marked differences in the enzyme content of intratubular epithelial casts.
Rapid Porphyrin Screening of Urine, Stool, and Blood
Authors: Haining Robert G , Hulse Thomas , Labbe Robert F 
Published: January 2020

Abstract
Simplified chemical screening tests and an apparatus to facilitate their performance have been developed for porphyrins. The tests are applicable to urine, stool, and blood. The procedures for different specimens are essentially identical and can be performed in a few minutes with a minimum of reagents and apparatus. Results obtained are usually sufficiently definitive to permit differential diagnoses of porphyrias and porphyrinurias without resort to separation or quantitation of the individual porphyrins.
Gas Chromatographic Analysis for Anticonvulsant Drugs in Biologic Fluids
Authors: Pippenger C E , Gillen H.W. 
Published: January 2020

Abstract
A rapid quantitative method for estimation of Mesantoin, Nirvanol, phenylethyl-malondiamide, phenobarbital, Mysoline, and Dilantin, in plasma, urine, and cerebro-spinal fluid by gas chromatography is described. A Jarrell-Ash flame ionization gas chromatograph with a 6-ft, 4-mm ID glass column packed with 1% HIEFF-8-BP on Gas Chrom Q 100/120 mesh was utilized. The pressure of nitrogen gas (carrier) at the inlet was 18 psi; temperatures: 260° at the injector, 250° in the column, and 295° at the detector.
The Detection of Basic and Other Drugs in Urine by Distillation and UV Spectrophotometry
Authors: Tompsett S L 
Published: January 2020

Abstract
An investigation has been described of the use of a distillation procedure, which is followed by UV spectrophotometry, for the detection and determination of a large number of volatile basic drugs in urine, The use of additional UV spectrophotometry and gas-liquid chromatography is described as follow-up procedures.
Estimation of Calcium, Magnesium, and Phosphorus in Diet and Stool
Authors: Husdan H , Rapoport A 
Published: January 2020

Abstract
A procedure that is simple and convenient for general use for the estimation of calcium, magnesium, and phosphorus in diet and stool is described. It includes a HNO3—HClO4 digestion in a micro-Kjeldahl flask. Calcium subsequently may be estimated by atomic absorption spectrophotometry or by the Clark-Collip procedure, magnesium by atomic absorption spectrophotometry, and phosphorus by the method of Fiske and SubbaRow. Chromium, used as a focal collection marker, does not interfere in the measurement of calcium and magnesium, whereas the measurement of phosphorus requires a preliminary ketone extraction of the chromium. The precision and accuracy of the procedure have been evaluated and found to be quite satisfactory.
A Simplified Procedure for the Assay of 5'-Nucleotidase
Authors: Rieder Sidney V , Otero Mirta 
Published: January 2020

Abstract
5'-Nucleotidase* activity is measured by inhibiting phosphatase activity with 0.01 M Ni+2 and eliminating the requirement for protein removal before measurement of phosphate. The normal range for adults is given as 1.6-14.0 units/liter of serum, with no apparent difference between the sexes.
Serum Glutamic Oxalacetic Transaminase Assay Using the Sequential Multiple Analyzer (SMA 12/30)
Authors: Moore John J , Sax Sylvan M 
Published: January 2020

Abstract
The SMA-12/30 method for serum glutamic oxalacetic transaminase assay gives higher values than are obtained with a reference spectrophotometric method for some serums. A modification of the manifold is made to permit the running of serum blanks. Blank corrections on 466 serum samples indicate that dialysis does not eliminate the need for the blank determination. Acetoacetate interferes in the SMA-12/30 method. The possibility of other interfering substances has not been ruled out.
Between-Bottle Variation as Source of Error in Quality Control Sera
Authors: Padmore G R A , Gatt J A 
Published: January 2020

Abstract
Between-bottle variation in relation to analytical error in the determination of constituents of the same batch of quality control serum has been examined statistically for sera from two manufacturers. Calcium and chloride were measured. Variation between bottles—as a result of errors in dispensing the original serum, lack of homogeneity, or reconstitution error—is less than the analytical error of the methods used here.
New Amylase Substrate and Assay Procedure
Authors: Babson Arthur L , Tenney Susan A , Megraw Robert E 
Published: January 2020

Abstract
This report describes a new procedure for serum amylase assay. A novel substrate, dyed amylopectin, is used that combines the advantages of saccharogenic and amyloclastic methods. Serum amylase hydrolyzes the dyed amylopectin into ethanol-soluble fragments, which are quantified colorimetrically after serum proteins and unhydrolyzed substrate are precipitated with alcoholic tannic acid. The substrate is prepared by coupling Reactone Red 2B to amylopectin in alkaline solution. Unreacted dye is removed by gel filtration. The clear red solution of dyed amylopectin is buffered and diluted to a standard concentration; it can be preserved indefinitely by lyophilization. The assay procedure is the following: 0.2 ml serum is added to 1 ml substrate at 37°C. After incubation for 10 min, 5 ml of alcoholic tannic acid are added, and the mixture is centrifuged. Absorbance of the supernatant solution at 540 nm is a linear function of amylase activity. Serum blanks are not required. The results correlate well with the saccharogenic assay of Somogyi.
Rapid Method for Homogenizing Tissue Samples for Liquid Scintillation Counting
Authors: Adams Lonnie D , Curry Larry L , Bartek Methodius J 
Published: January 2020

Abstract
Quick-freezing in liquid nitrogen allows a great variety of animal organs, including those rich in connective tissue, to be rapidly and completely pulverized, thus rendering them more readily soluble in the mixture used for scintillation counting. We have constructed a pulverizing assembly from items normally found in the research laboratory that conveniently facilitates this operation.
Automated Method for Determination of Serum Calcium by Use of Alizarin
Authors: Frings Christopher S , Cohen Patricia S , Foster Lowell B 
Published: January 2020

Abstract
An automated method is described for determining serum calcium by measuring the red chromogenic complex formed by calcium and alizarin. About 40 µl of undialyzed serum is added directly to one reagent to pro-duce the color, which follows Beer's law at 599 nm to a concentration of 15.0 mg of calcium per 100 ml, with a coefficient of variation of 2.5%. Serum calcium concentrations, as measured by our method, compare favorably with those by the corresponding manual method and by atomic absorption spectrophotometry
Measurement of Human Serum Ceruloplasmin by Its p-Phenylenediamine Oxidase Activity
Authors: Sunderman F William , Nomoto Shozo 
Published: January 2020

Abstract
Optimum reaction conditions were evaluated for assay of serum ceruloplasmin by measurement of its p-phenylenediamine oxidase activity. The pH optima of p-phenylenediamine oxidase activities of human and rat ceruloplasmins were 5.45 and 5.2, respectively. The p-phenylenediamine oxidase activity of rat ceruloplasmin was markedly inhibited by phosphate (0.1 mol/liter), that of human ceruloplasmin only slightly. These reaction conditions were judged to be optimum for the ceruloplasmin assay: (a) substrate: p-phenylenediamine dihydrochloride, 8.9 mmol/liter; (b) buffer: acetate, 0.1 mol/liter; (c) chloride concentration: 21 mmol/liter; (d) serum dilution: 31-fold; (e) incubation: 37°C for 30 min; (f) spectrophotometry: 530 nm (vs. a "serum blank" containing NaN3). Using these reaction conditions, we devised an improved technique for measuring serum ceruloplasmin. The coefficients of variation of replicate analyses by this technique were 1.25% (for "within-run" precision) and 2.8% (for "day-to-day" precision). The mean concentration of ceruloplasmin in sera from 29 healthy men was 0.315 g/liter (SD = ± 0.049, range = 0.233 to 0.402).
Apparatus for Collecting Fractions from Density Differential Interfaces and Its Use in Gravimetric Measurement of Total Myelin
Authors: Hill Robert M , Bruzek Virginia E 
Published: January 2020

Abstract
An apparatus is described for the precise preparation of density differential interfaces and for quantitative collection of samples from these interfaces. A method is described in which the apparatus is used to quantitatively extract and measure myelin from nerve tissue. Myelin is separated from a homogenate of nerve tissue by density differential ultracentrifugation. The washed myelin is dried. The rate of drying undergoes a sharp change when the loss of free water gives place to the loss of structural water. These two rates are used to calculate the quantity of normally hydrated myelin present.
Isolation and Quantification of Serum Uric Acid by Adsorption Chromatography
Authors: Simkin Peter A 
Published: January 2020

Abstract
Established methods for determining the serum uric acid concentration are colorimetric, enzymatic, or combination of the two. An alternative method, based on the affinity of purines for polyacrylamide resin, has been developed. Uric acid, more strongly adsorbed than other major serum constituents, elutes later (with phosphate buffer, pH 7) from a polyacrylamide column. The separated serum uric acid is measured by continuously monitoring the ultraviolet absorptivity of the column effluent. Uric acid is separated satisfactorily from its metabolites, a feature useful in studies of the metabolism of radiolabeled uric acid.
An Automated Micromethod for Determination of Serum Glucose, with an Improved o-Toluidine Reagent
Authors: Moorehead Wells R , Sasse Edward A 
Published: January 2020

Abstract
An automated method has been developed in which a new o-toluidine reagent is used for the microanalysis of glucose. The reagent is 1.3 times as sensitive as the o-toluidine reagent commonly used in manual procedures. The reagent does not significantly alter the life expectancy of manifold tubing made of polyvinyl chloride. The automation includes a dialysis step and possesses the desirable features of the manual methods, including the greater specificity as compared with methods based on reducing properties. Results of this automated method obey Beer’s law, are very reproducible (the coefficient of variation is approximately 1.5%), and are not significantly different from those obtained manually. The method requires 75 µl of sample.
A Method for Determining Nitrofurantoin in Urine in the Presence of Phenazopyridine Hydrochloride and Its Metabolites
Authors: Hollifield R D , Conklin John D 
Published: January 2020

Abstract
The high urinary drug concentrations usually encountered after administering nitrofurantoin in the chemotherapy of urinary tract infections are often measured by the nitromethane—Hyamine method. We show here that, if the urinary tract analgesic, phenazopyridine hydrochloride, and its related metabolite(s) are in the urine, they interfere with this determination of nitrofurantoin. Nevertheless, the nitromethane—Hyamine method may be modified to determine nitrofurantoin quantitatively in urine collected from human subjects who have been treated with the analgesic and nitrofurantoin concomitantly.
Nomograms for Calculation of Urea Clearance
Authors: Gindler E Melvin 
Published: January 2020

Abstract
Two nomograms are given for use in calculating standard, C[unknown], or maximum, Cm, urea clearance. The first nomogram calculates the urine flow rate, f, from the urine collection time and volume data. With the second nomogram, values of f and urea nitrogen concentrations in blood serum (or plasma) and urine are used to calculate either C[unknown] or Cm, according to the value of f. There is no intermediate calculation of √f. Examples of the use of the two nomograms in the calculation of C[unknown] or Cm are given.
Evaluation of a New Procedure for Measuring Serum Creatine Kinase Activity
Authors: Henry Wilkinson J , Steciw B 
Published: January 2020

Abstract
A new spectrophotometric microtechnique for the determination of serum creatine kinase activity, in which all reagents are provided in a single com-pressed tablet, has been evaluated. The procedure depends upon coupling the creatine phosphate-ADP reaction with the hexokinase and glucose-6-phosphate dehydrogenase reactions. The new technique is quick, relatively simple, and gives results which compare favorably with the conventional spectrophotometric method in precision and sensitivity. It requires a sample volume of 10 Al, and values ranging from 10 to1600 U/liter can be determined without dilution. Gross hemolysis leads to erroneously high values, but the error is negligible with slightly hemolyzed specimens. A provisional normal range has been established
Determination of Fecal Triglycerides and Fatty Acids of Medium Chain Length by Electrical Capacitance and by Petroleum Ether Extraction
Authors: Hallaway Ben E , Sandberg Rodney 
Published: January 2020

Abstract
The extraction method of Friedner and Moberg for determining fecal lipids gave recoveries of medium-chain triglycerides and of octanoic and decanoic acids from stool specimens averaging 103, 97, and 107%, respectively. Fatty acids did not esterify appreciably during extraction. Accordingly, this method is suitable for use in measuring intestinal absorption of triglycerides of medium chain length. The electrical capacitance method of Wolochow et al. is unsuited to the determination of total lipids in a mixture of triglycerides and fatty acids of long and medium chain length because these substances differ widely in capacitance.
A Simple Screening Method for Detecting Isovalerylglycine in Urine of Patients with Isovaleric Acidemia
Authors: Ando Toshiyuki , Nyhan William L 
Published: January 2020

Abstract
Isovaleric acidemia is one of an enlarging group of inherited metabolic diseases now recognized to cause death in the neonatal period. Rapid, simple detection is essential for diagnosis of these conditions. We describe a method that fulfills these criteria for isovaleric acidemia. Excretion of isovalerylglycine in the urine more reliably indicates the condition than the presence of volatile isovaleric acid in the blood. Isovalerylglycine is extracted from urine and separated by thin-layer chromatography from other constituents of urine. It is detected by spraying the chromatogram with bromcresol purple. Isovalerylglycine does not appear in normal urine.
Two-Dimensional Thin-Layer Chromatography on Two-Layer Plates of Amino Acids
Authors: Kraffczyk F , Helger R , Lang H 
Published: January 2020

Abstract
Separation of the amino acids in urine by use of thin-layer chromatography (TLC) has hitherto required that the specimen be first desalted and then chromatographed in two dimensions with at least two pairs of developing solvent systems. We wished to simplify both steps. The customary method of desalting on a column is replaced by desalting on a plate that supports a strongly acid cation-exchanger and a cellulose layer. This method, originally developed for one-dimensional TLC, is used here for two-dimensional TLC. Urine is applied to the ion-exchange layer and strong acids and neutral substances are removed with water. The amino acids are then chromatographed into the cellulose layer, and are separated there two dimensionally with a newly devised pair of developing solutions. This pair of solvents separates nearly all of the amino acids in urine.
Ultraviolet-Absorbing Compounds in Urine of Normal Newborns and Young Children
Authors: Vavich Joel M , Howell R Rodney 
Published: January 2020

Abstract
Ultraviolet-absorbing compounds excreted in the urine of normal newborns, infants, and children have been measured by high-pressure anion-exchange chromatography. The chromatograms increased in complexity with increasing age of the subject. Preliminary data indicate that the excretion of pseudouridine and uridine was significantly higher in newborns and infants than in older children and adults. Excretion of hippuric acid was low in the newborn. Excretion of ergothioneine was lower in older children than in newborns, infants, or adults. However, hypoxanthine excretion was constant in all groups.
Semiautomated Method for Measurement of Dopa in Plasma
Authors: Spiegel Herbert E , Tonchen Alice E 
Published: January 2020

Abstract
A semiautomated fluorometric method for analysis of dopa [3-(3,4-dihydroxyphenyl)-L-alanine] is described, with ferricyanide used as an oxidant. To separate dopa from interfering catecholamines it is adsorbed on alumina, eluted with 0.1N HCl, then adsorbed on and eluted from a cation-exchange column. The method is suitable for use with a large volume of samples. It provides a simple, sensitive, accurate, and reproducible analytical technique for routine use.
Emergency Screening of Urine, Plasma, or Gastric Contents for Barbiturates
Authors: Helman Edith Zak 
Published: January 2020

Abstract
A procedure is described for emergency screening for barbiturates that requires no specialized equipment and can be performed in less than 10 min; thus lending itself to emergency-room use. The method is highly specific and can be used to detect as little as 1 mg/100 ml.
Absence of Measurable Leukocyte Alkaline Phosphatase Activity from Leukocytes of Patients with Chronic Granulocytic Leukemia
Authors: DeChatelet Lawrence R , Cooper M Robert , McCall Charles E 
Published: January 2020

Abstract
Leukocyte phosphatase activity was determined over a broad pH range. Using this procedure, we found no alkaline phosphatase activity in leukocytes from three patients with chronic granulocytic leukemia. The low values usually reported for this disease are actually attributable to acid phosphatase activity, which is slight but measurable at alkaline pH.
Comparison of Serum Calcium Measurements Obtained with the SMA 12/60 and by Atomic Absorption Spectrophotometry
Authors: Gambino S Raymond , Fonseca Ivelice 
Published: January 2020

Abstract
Comparable results are obtained when serum calcium is measured by a colorimetric cresolpthalein method on the Technicon SMA 12/60 and by atomic absorption spectrophotometry (Instrumentation Laboratory Model 153 instrument), with strontium as an internal standard. Sera from 250 patients with abnormal calcium concentrations, ranging from 4.9 mg/100 ml to 9.0 mg/100 ml, were measured by each method; the difference between the means for each method was only 0.04 mg/100 ml. The standard deviation of the difference between paired results was ±0.16 mg/100 ml. We were unable to discover any effect of drug or disease on the colorimetric assay, which therefore is suitable for use in large-scale surveys. On the other hand, the more precise atomic absorption spectrophotometry is suitable for use as a reference method. In addition, with an internal standard it is fast and simple, making it suitable for emergency assays of calcium 24 h a day.
An Initial Reaction Rate Assay for "Glycerate Dehydrogenase"
Authors: McQueen M J , King J 
Published: January 2020

Abstract
Concentrations of substrate, coenzyme, and hydrogen ion, optimal for the reduction of hydroxypyruvate at 37°C by normal and pathological human sera are described. We confirmed, by using the supernatant fluid from homogenized human heart and liver tissue, that the faster-moving isoenzymes have a greater affinity for substrate and coenzyme than the slowermoving isoenzymes, which require higher concentrations for saturation. LDHx, present in human seminal plasma, appears to have the lowest Michaelis constant for hydroxypyruvate. Glycerate dehydrogenase was found to be stable if the standard assay temperature was increased from 25° to 37°C.
A Clinically Useful Method for Determining Erythrocyte Sodium and Potassium
Authors: Helbock Harold J , Brown David M 
Published: January 2020

Abstract
A method is presented for determining erythrocyte sodium and potassium concentration. Heparinized whole blood is separated into cellular and plasma fractions in large-bore capillary tubes. An aliquot of the erythrocyte fraction is then pipetted directly into lithium chloride diluent and the electrolytes determined flame photometrically. Plasma trapping is measured with 14C-inulin and corrections calculated for trapped sodium and potassium. This technique is rapid, simple, and can be performed as a routine procedure by most clinical laboratories.
Comparison of Two Methods for Determining Amylase Activity in Serum and Urine
Authors: Chung Kim Y , Sinha Ram M , Trew J Allan 
Published: January 2020

Abstract
Two methods for estimating amylase activity in serum and urine are compared. A method that uses a chromogenic substrate in a kit was shown to be preferable over the older amyloclastic procedure, which uses starch substrates. The precision of both methods was determined.
Measurement of Lead in Biological Materials by Combined Anion-Exchange Chromatography and Atomic Absorption Spectrophotometry
Authors: Lyons Harold , Quinn F E 
Published: January 2020

Abstract
A method for determination of lead in blood, urine, and tissue is presented. This procedure combines the selective concentration of lead by, and the elimination of large quantities of alkali metals on, an anion-exchange resin with the speed and accuracy of determination by atomic absorption spectrophotometry.