bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simplified Method for the Estimation of Inorganic Phosphorus in Body Fluids
Authors: Goldenberg Harry , Fernandez Alberto 
Published: January 2020

Abstract
A simplified procedure is described for the determination of inorganic phosphate in body fluids. The method employs two stable reagents and requires a minimum number of steps. Serum is deproteinized with trichloroacetic acid containing ferrous ion and thiourea. The supernatant is decanted and mixed with a small volume of molybdic acid. The phosphomolybdate formed is immediately reduced in situ by the ferrous ion to produce a blue color that is stable for several hours. The intensity of color is insensitive to changes in concentration of acid, molybdate, ferrous ion, and thiourea, and to losses in decanting the serum supernatant. Excellent conformity to Beer's law is demonstrated over a wide range of phosphorus concentrations. Recoveries of phosphorus added to serum and urine are shown to be quantitative. A comparison is presented between this method and that of Fiske and SubbaRow (1).
A Multichannel Continuous-Flow Analyzer
Authors: Thiers Ralph E , Bryan Jean , Oglesby Katherine 
Published: January 2020

Abstract
A 10-channel analyzer is described with which sodium, potassium, chloride, carbon dioxide, calcium, phosphorus, total protein, albumin, albumin blank, and uric acid levels may be determined simultaneously. Operating at the rate of 60 specimens per hour, the instrument uses less than 1 ml. of serum for all 10 determinations. The results appear on 5 two-pen recorders. The report describes the instrument, its operating characteristics, modification of the sampler module to enable sampling from test tubes, a manual system of rapid data-handling, and the system employed for nearly anaerobic sample-handling.
Profile of Admission Chemical Data by Multichannel Automation: An Evaluative Experiment
Authors: Bryan D Jean , Wearne Judith L , Viau Alberto , Musser A Wendell , Schoonmaker Fred W , Thiers Ralph E 
Published: January 2020

Abstract
In an experiment comparing the clinical chemical data obtained for incoming hospital patients from samples of blood submitted to the routine laboratory and from samples analyzed automatically, a multichannel analyzer was employed. The constituents determined, chosen on the basis of the frequency with which they were ordinarily requested, were glucose, urea, sodium, potassium, chloride, carbon dioxide content, calcium, phosphorus, total protein, albumin, and uric acid. In a significant fraction of the patients admitted at three different hospitals the profile of admission chemical determinations indicated abnormal values which had not been sought by the physician and which often were of direct help to him and benefit to the patient.
An Improved Method for Determination of Serum Albumin and Globulin
Authors: Fernandez Alberto , Sobel Charles , Goldenberg Harry 
Published: January 2020

Abstract
A simple and reliable method has been developed for the analysis of serum proteins. Globulins are precipitated from serum with HCI- ethanol. The albumin remains in the supernatant fluid. The albumin fraction is then precipitated by alcoholic sodium acetate. The proteins are redissolved and determined colorimetrically following their reaction with the biuret reagent.
Recovery and electrophoretic studies indicate that the method affords a clean-cut separation of albumin from the globulin fraction. Lipemia does not appear to interfere with the analysis.
Solubility Determination of Cholesterol Polymorphs in Organic Solvents
Authors: Stauffer Royce D , Bischoff Fritz 
Published: January 2020

Abstract
In a study of the solubility of crystalline forms of cholesterol in various solvents, the solubilities (per cent by weight) of cholesterol needles and hydrated plates at 38° were, respectively, 4.0 and 3.2% in olive oil; 2.6 and 1.9% in tetradecane; 26.2 and 9% in toluene; and 21.0 and 7% in cyclohexane. When these solvents are in equilibrium with an aqueous phase, needles are converted to plates. Pseudomorph ( dehydrated) plates in olive oil have the solubility of needles. These differences may have significance in studies involving cholesterol pathogenesis.
The modified Zak reaction with ethanol could not be used for the assay of cholesterol in olive oil since the reaction product was turbid. Higher alcohols were studied as a substitute for ethanol; 2-propanol was satisfactory.
Human Plasma and Serum Trypsin-like Esterase Activity
Authors: Rutkowski Roman B 
Published: January 2020

Abstract
A spectrophotometric method using benzoyl arginine ethyl ester (BAEE) is described for the assay of serum and plasma trypsin-like esterase activity. The method was used to find activities in serum and plasma (anticoagulated with oxalate and heparin) from 12 healthy males at 3 different reaction pH's.
The effects of calcium, oxalate, heparin, soybean trypsin inhibitor, ovomucoid, and heat on this activity were also measured. Values of esterase activity were significantly different, indicating a variable enzyme or inhibitor composition in the 3 sets of samples. Plasma from heparinized blood gave unique activity responses to pH and to the agents tested for effect.
Microdetermination of Protein Nitrogen with a Dumbbell Diffusion Apparatus
Authors: Nobel Deana 
Published: January 2020

Abstract
The use of a two-chamber, sealed microdiffusion apparatus has been investigated for the determination of protein nitrogen on samples containing 0.5 mg. protein. The apparatus is constructed from a ground-glass ball-and-socket joint, and all operations including digestion are performed in the designed apparatus. The method has been applied to the determination of nitrogen in tobacco mosaic virus protein and found to be in good agreement with theoretical values.
Automatic Method for the Determination of Calcium in the Presence of Magnesium and Phosphate Ions
Authors: Smith Preston , Kurtzman Caroline H , Ambrose Mary E 
Published: January 2020

Abstract
A direct spectrophotometric method for manual analysis of calcium using the indicator dye Eriochrome Blue S. E. was selected for automation. Most indicator dyes used have been somewhat unstable in solutions sufficiently alkaline to minimize the interference of magnesium. Eriochrome Blue S. E., when kept in an ice bath in the absence of light, permitted the use of sufficient alkali to remove interfering magnesium ions. Magnesium did not interfere in concentrations up to 12 mg./100 ml. when added to standards. The addition of 0.5% (w/v) citric acid removed interference of phosphate in concentrations up to 300 mg./100 ml.
The automated method has the advantage of speed, yet retains the accuracy and precision of the conventional methods used for determining calcium.
Serum Glutamic-Oxaloacetic Transaminase Activity: Diagnostic Accuracy of the Revised Spectrophotometric and the Dinitrophenylhydrazine Methods
Authors: Amador Elias , Franey Robert J , Massod Mary F 
Published: January 2020

Abstract
The diagnostic accuracy of two methods for measuring serum glutamic-oxaloacetic transaminase activity was examined in 50 cases of acute myocardial infarction proven by autopsy and in 12 nonfatal cases documented by rigid clinical criteria. All activities measured with the revised spectrophotometric method were elevated during the second day after infarction, and all patients had an elevated activity. The spectrophotometric method therefore had a diagnostic accuracy of 100%.
Activities measured with the dinitrophenylhydrazine method of Reitman and Frankel were elevated in only 68% of cases during the second day after infarction, and the activity was elevated in only 76% of all the patients during the first 4 days. Dinitro-phenylhydrazine-measured activities were therefore 20-30% inaccurate. The diagnostic inaccuracy of the dinitrophenylhydrazine method could result in 300,000 false-negative diagnoses of acute myocardial infarction each year in the United States alone.
Effect of a Nonionic Detergent on the Spectral Absorption of Oxyhemoglobin in the Presence of Bilirubin
Authors: Jackson Sanford H 
Published: January 2020

Abstract
The presence of the nonionic detergent Brij 35 in a solution of oxyhemoglobin and bilirubin has been found to change the spectral transmission curve of the oxyhemoglobin. The major change is in the 475 mµ region, where the transmission is greatly increased. A combination of the bilirubin with the oxyhemoglobin by an intermediate linkage with the Brij is postulated.
Automated Methods for Blood Glucose and Urea with Adaptation for Simultaneous Determination
Authors: Fingerhut Benjamin , Ferzola Rocco , Marsh Walton H , Miller Alfred B 
Published: January 2020

Abstract
Automated blood glucose and urea nitrogen procedures have been modified for use with the Technicon 15-mm. tubular flow-cell colorimeter to take advantage of the resulting increased sensitivity and economy. Flow diagrams for these procedures as well as for the simultaneous determination of glucose and urea are presented. Recovery and reproducibility data are given to indicate the reliability of these methods.
Studies of Some Indole Compounds Isolated from the Urine of a Mentally Retarded Child
Authors: Fischl J , Israel S 
Published: January 2020

Abstract
During the investigation of the urine of a mentally retarded child, a number of indole compounds were isolated. Gel filtration of the native urine gave three chief fractions. phatase fraction of blood had properties unlike that of the red blood cell enzyme and
Extraction methods available for the isolation of the abnormal indoles in large amounts resulted in irreversible structural changes, probably detachment of the carboxy groups, with loss of electrophoretic mobility, changes of chromatographic properties, and decreased water solubility.
It is presumed that the presence of the abnormal indoles isolated is the result of disturbed metabolism of the aromatic amino acids.
An Automated Method for the Determination of Serum Organic Iodine
Authors: Simpson D 
Published: January 2020

Abstract
The accuracy and reproducibility of an automated method has been assessed and the normal range for total serum organic iodine found to be 3.9-7.5 µg./10O ml., mean 5.7 µg./100 ml. Preliminary resin treatment of serum has been shown to be effective in removing normal concentrations of inorganic iodine. In the case of serums having grossly elevated inorganic iodine levels of up to 100 µ g./10O ml., the resin extracts more than 96% of the halide, but the unabsorbed iodine may invalidate the estimation. The resin can extract organic iodine from serum but the process occurs very slowly and it is of practical importance only if serums are allowed to stand over resin for longer than 24 hr.
Applications of Computer Produced Frequency Distribution Curves
Authors: Ressler N , Whitlock L S 
Published: January 2020

Abstract
A method is described for determining the diagnostic significance of test results. It is based upon the relation of a test value to a frequency distribution curve of patients with a particular disease, and to a curve of others without that disease. When the two curves overlap at the test value found, the results are evaluated in terms of the probability of the patient corresponding to either of the two curves. The evaluation of results in terms of probabilities is more descriptive than the classification of all answers as either "normal" or "abnormal" and permits the combination of probabilities obtained from a number of tests into a single, resultant probability. The most probable diagnosis of a given patient, based upon all the tests done, or the most discriminating combination of tests for the diagnosis of any disease can be determined. The method permits compensation for such factors as a patient's age and sex, or the stage of a disease. It is nonparametric, and can be performed automatically with a data-processing system.
Determination of Calcium in Urine and Serum by Atomic Absorption Spectrophotometry (AAS)
Authors: Trudeau David L , Freier Esther F 
Published: January 2020

Abstract
The determination of calcium in biologic fluids by atomic absorption spectrophotometry is interfered with by the presence of protein, cations, and those anions that form complexes with calcium. Such interference was overcome when lanthanum was included in a 1:50 dilution of serum or urine. Recovery of calcium added to calcium-free serum was 100%. The S.D. based on double-blind duplicates was 0.22 mg./lOO ml. Excellent statistical agreement was found between the test method and each of the 2 reference methods.
Distribution Patterns of Uric Acid in Coronary Artery Disease
Authors: London Morris , Hums Mary 
Published: January 2020

Abstract
The uric acid levels in each of 335 cardiac patients were studied over a period of more than 3 months from the onset of the acute stage of coronary heart disease. Comparison was made with uric acid values obtained from a group of 316 normal subjects. Male patients with arteriosclerotic coronary artery disease with infarction generally exhibited rising concentrations of serum uric acid during the first weeks after an attack and a gradual return toward normal levels after 3 months. Female patients of the two groups studied and male patients with arteriosclerotic coronary artery disease, but without infarction, had uric acid levels averaging much higher than those of the control group.
Determination of Calcium and Magnesium in Serum, Urine, Diet, and Stool by Atomic Absorption Spectrophotometry
Authors: Gimblet Elizabeth G , Marney Amy F , Bonsnes Roy W 
Published: January 2020

Abstract
Atomic absorption spectrophotometry was evaluated as a method for the determination of calcium and magnesium in serum, urine, diet, and stool, and was found a most suitable technic for a large clinical chemistry laboratory.
Dumbbell-Diffusion Screening for Carbon Monoxide, Volatile Alcohols, and Chlorinated Hydrocarbons in Blood
Authors: Nobel Sidney , Ricker Alyne 
Published: January 2020

Abstract
Rapid screening tests for the detection of carbon monoxide, ethanol and other volatile alcohols, and chlorinated hydrocarbons in blood are presented. The dumbbell-diffusion cell used was found to be versatile in allowing reactions to be carried out at either room temperature or 1000 and in acting as a support for pretreated paper discs.
Effects of Tomatine on the Colorimetric Determination of Cholesterol by the Zak Procedure
Authors: Eskelson Cleamond D , Dunn Arthur L , Cazee Clarence R 
Published: January 2020

Abstract
The iron-acetic acid reagent used for cholesterol determinations produces a color with tomatine, which is reported to be a more specific precipitant for cholesterol. To circumvent the interferen:e of tomatine found in a cholesterol-tomatinide complex, a standard solution containing stoichiometric amounts of tomatine and cholesterol was used and proved to be reliable for the determination of free cholesterol in serum.
The Clinical Chemistry and Pathologic Physiology of Thyroid Tissue
Authors: Stanbury J B , DeGroot Leslie J 
Published: January 2020

Abstract
Familial goiter with hypothyroidism can be subdivided into at least 8 groups and each appears to result from an inherited disorder at a specific stage in thyroid hormone synthesis, mobilization, or peripheral effect. At times, the intense hyperplasia which accompanies one of these disorders evolves into malignant disease. Criteria for diagnosis of each are presented.
Enzymatic Abnormalities in Diseases of Sphingolipid Metabolism
Authors: Brady Rascoe O 
Published: January 2020

Abstract
Biochemical investigation employing labeled sphingolipids has become a useful technic for determining the metabolic lesions in the sphingolipidoses. With these procedures, specific enzymatic defects have been demonstrated in Gaucher's disease, Niemann-Pick disease, Fabry's disease, and in metachromatic leukodystrophy. As suitable substrates become available, this method will be useful for elucidating the nature of the lesions in Tay-Sachs disease and generalized gangliosidosis.
Enzymatic assays with labeled compounds performed on biopsy specimens from various tissues and white blood cell preparations have been helpful in establishing the diagnosis of the sphingolipidoses. Tissue cultures obtained from patients with Niemann-Pick disease show diminished sphingomyelin-cleaving enzyme as compared with control enzyme levels. Tests such as these should be of considerable diagnostic and prognostic usefulness, as well as being helpful adjuncts for the selection of proper therapeutic measures.
Continuous Spectrophotometric Measurement of Serum Alkaline Phosphatase Activity
Authors: Bowers George N , Kelley Mari-Lou , McComb Robert B 
Published: January 2020

Abstract
Findings with 9 self-indicating phenolic substrates for alkaline phosphatase assay by continuous spectrophotometric technic demonstrate that not only specific reaction conditions, e.g., buffer type, molarity, and pH, contribute significantly to the final observed "Sensitivity" attributed to any 1 substrate but also the following variables must be considered: (1) the enzyme's tissue and species source; (2) the molar absorptivity difference between the substrate and its dephosphorylated product; and (3) the molecular activity.
Sulfur Content of Paper Electrophoretic Fractions In Human Serum
Authors: Natelson Samuel , Stellate Rodney 
Published: January 2020

Abstract
Instrumentation is described for scanning paper electrophoretic strips for the sulfur distribution of the fractionated serum proteins with the vacuum X-ray spectrometer. Paper electrophoretic patterns of serum proteins scanned by X-ray spectrometry for sulfur content of the various fractions and by protein staining are compared.
For 26 blood donors, the mean percentages of sulfur found in the different fractions were: albumin, 1.64; and globulins: alpha1, 0.63; alpha2, 1.10; beta, 1.14; and gamma, 0.98. The procedure was then applied to the serum of patients with diseases of the liver and of the kidney, various types of malignancies, and other diseases.
The percentage of sulfur in abnormal fractions varies widely. This permits, in some cases, detection of abnormal peaks which would otherwise be missed by protein staining alone.
This technic should be of value in the identification and classification of abnormal protein fractions, when combined with studies by the ultracentrifuge and immuno-electrophoresis.
Determination of Neutral Urinary 17-Oxosteroids with Hydroxide of Hyamine 1O-X in the Zimmermann Reaction
Authors: Bjerre Solveig , Kita Rose 
Published: January 2020

Abstract
A modified method for 17-oxosteroid determination is described. The organic base, hydroxide of Hyamine lO-X,° which is stable in methanol, has replaced the unstable ethanolic potassium hydroxide solution in the Zimmermann reaction. Maximal color development was studied by varying incubation temperature, time, m-dinitrobenzene, and concentration of hydroxide of Hyamine 10-X. An incubation temperature of 37° for 30 min., with 1% m-dinitrobenzene in 1 M Hyamine 10-X hydroxide solution, gave close to maximal color.
The major urinary 17-oxosteroids, dehydroepiandrosterone, androsterone, and etiocholanolone, gave similar chromogenic values. However, C3 and C20 oxosteroids produced some color in the Zimmermann reaction, and thus if present in large amounts, interfere.
The interference in vitro of 35 drugs was tested, and several drugs were found to interfere.
An essentially pigment-free urinary extract was obtained during the washing step, by addition of water to the ethylene dichloride extract containing sodium hydroxide pellets.
Comparative 17-oxosteroid studies of urine specimens from laboratory personnel and from patients were performed, based on absorbance at a single wavelength (520 mµ) and at three wavelengths (Allen correction). Correlation coefficients for the laboratory personnel were .983 for females and .996 for males; for the patients, .974 and .975, respectively.
Automated Colorimetric Determination of Free Fatty Acids in Biologic Fluids
Authors: Dalton C , Kowalski C 
Published: January 2020

Abstract
For the routine determination of free fatty acids (FFA) the authors recommend a modification of the automated colorimetric method of Antonis (1) using the extraction procedure of ltaya and Ui (2). This direct extraction and automated analysis shows good correlation with Trout's (3) modification of Dole's (4) titrimetric procedure.
Measurement and Standard Reference Materials in Clinical Chemistry
Authors: Young Donald S , Mears Thomas W 
Published: January 2020

Abstract
The concepts of the measurement system based upon four parameters—length (meter), mass (kilogram), time (second), and temperature (kelvin)—are developed. The proper daily operation of an analytic laboratory depends upon these basic measurements and others derived from them, e.g., the liter. An additional component of chemical measurement which directly influences accuracy is the purity of the standards and reagents employed. The standard reference materials program of the National Bureau of Standards provides a central source of guaranteed high-purity reference materials which are available to all. The reliability of chemical measurements should increase as new standard reference materials such as cholesterol, uric acid, urea, and creatinine are utilized to standardize methods and to calibrate instruments in the clinical laboratories of this country.
Radioimmunoassay of Human Growth Hormone
Authors: Knoller Mechthilde , Tsao M U , Lowrey George H 
Published: January 2020

Abstract
Detailed methods for: (1) 131I iodination of human growth hormone (HGH); (2) purification of labeled HGH (HGH-131I; and (3) radioimmunoassay of HGH are given. Bio-Gel filtration is introduced as a rapid and reproducible method for purifying HGH-131I which has been obtained by a modification of the method of Greenwood et al. (1). Highly purified HGH-131I with a bindability of 96% or more is usually achieved.
Semiautomated Assay of Normal Concentrations of Urinary Glucose by an Enzymatic Fluorometric Technic
Authors: Scherstén Bengt , Tibbling Gunnar 
Published: January 2020

Abstract
A semiautomated, enzymatic, fluorometric method for the determination of the low glucose concentrations normally present in urine from subjects in the fasting state is described. The method is developed from a manual, enzymatic, fluorometric technic for the determination of urinary glucose using hexokinase (HK) and glucose-6-phosphate dehydrogenase (G-6-PDH). The procedure is based on measurements of the fluorescence of reduced nicotine amide adenine dinucleotide-phosphate (NADPH2) which is formed in proportion to the glucose content of the sample. The unspecific fluorescence of urine is almost completely removed by treating the urine with a mixed ion-exchange resin prior to applying the automated procedure. The chief advantage of the method is that it may afford an opportunity for low-cost screening for detection of bacteriuria.
Duodenal Fluid pH in Cystic Fibrosis
Authors: Knauff R E , Adams J A 
Published: January 2020

Abstract
Attention is directed here to the major discrepancies among duodenal fluid pH measurements in cystic fibrosis. A series of 9 cystic fibrosis and 9 control subjects were found to have duodenal fluid pH values of 4.8 ± 0.7 and 6.3 ± 0.2, respectively.