bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automated Fluorometric Method For The Determination of Serum Calcium
Authors: Fingerhut Benjamin , Poock Alfred , Miller Henry 
Published: January 2020

Abstract
An automated fluorometric procedure for serum calcium has been developed which can be used for a wider variety of pathologic serums than the automated fluorometric and colorimetric technics generally being used at present. The method is based upon measurement of the fluorescence produced by calcein with calcium in a serum dialysate. Results are in good agreement with the Clark-Collip procedure. Recovery experiments averaged 98-101%. The standard deviation for duplicate determinations averaged ±0.20 mg/100 ml.
Direct Manual Determination of Serum Total Cholesterol with a Single Stable Reagent
Authors: Wybenga D R , Pileggi V J , Dirstine P H , Giorgio John Di 
Published: January 2020

Abstract
We describe a simple, direct, and specific manual method for quantitative determination of total cholesterol in serum. In the method, which requires no extraction of the serum, a single stable reagent and 50 µl of sample is used. Serum cholesterol concentrations determined by this method did not differ statistically from those obtained by the reference method of Abell et al. Hemoglobin, bilirubin, and γ-globulin do not interfere unless present at markedly supranormal concentrations. Inter-run precision is about ±3% (95% confidence limits).
Determination of Amphetamine, Methamphetamine, and Related Amines in Blood and Urine by Gas Chromatography with Hydrogen-Flame Ionization Detector
Authors: Lebish Paul , Finkle Bryan S , Brackett J W 
Published: January 2020

Abstract
A sensitive gas-chromatographic method suitable for clinical and forensic purposes is presented for measuring methamphetamine, amphetamine, and other phenethylamines in blood and urine. When testing blood, we include a known quantity of a homologous standard, n-propylamphetamine hydrochloride, in the tungstic-acid solution used to precipitate blood proteins; the acid filtrate is washed, alkalinized, and extracted with ether. Extracted phenethylamines are converted to the corresponding acetamides, which are then concentrated and gas-chromatographed. The method for urine is similar except the known quantity of n-propylamphetamine hydrochloride is added to the sample, the protein precipitation is omitted, and chloroform is the extracting solvent. Suitable tests are described for the more stringent confirmation of amphetamine and methamphetamine required for court testimony. Retention data obtained from both a polar and a nonpolar column packing are presented for over 50 compounds related to phenethylamine.
Cerebrospinal Fluid Proteins: Concentration by Membrane Ultrafiltration and Fractionation by Electrophoresis on Cellulose Acetate
Authors: Windisch Rita M , Bracken Mark M 
Published: January 2020

Abstract
A membrane ultrafiltration system is described and evaluated for rapidly concentrating cerebrospinal fluid before cellulose acetate electrophoresis. Results with this system were compared with those obtained by use of vacuum ultrafiltration through a collodion sac. Mean values for the various protein fractions were determined for normal cerebrospinal fluid. The results, in percentage of total protein, after membrane and vacuum ultra-filtration concentration were, respectively: 3.8 and 5.2% prealbumin, 65.5 and 63.9% albumin, 3.6 and 3.6% ∝1-globulin, 6.8 and 6.1% arglobulin, 12.4 and 12.9% a-globulin, and 7.6 and 8.2% γ-globulin.
Rapid Method for Determining Alkaline Phosphatase Activity in Serum with Thymolphthalein Monophosphate
Authors: Roy A V 
Published: January 2020

Abstract
The use of sodium thymolphthalein monophosphate in measuring alkaline phosphatase activity of serum is described. Thymolphthalein liberated in the reaction is conveniently measured by raising the pH of the medium, which produces a color and also stops the hydrolysis. The effects of pH, kind and molarity of buffer, temperature, and enzyme and magnesium con-centrations were studied. Results by this procedure correlate well with those obtained by a standard procedure in which liberated p-nitrophenol is de-termined. Advantages of the present method include excellent linearity, high precision, short incubation, and reagent stability.
Plasma Fibrinogen: Determination, Normal Values, Physiopathologic Shifts, and Fluctuations
Authors: Grannis George F 
Published: January 2020

Abstract
The determination of plasma fibrinogen, either as clottable protein or protein precipitable with glycine or ammonium sulfate, is evaluated in terms of principles of analysis, analytic error, normal and abnormal ranges, physiologic stability, and pathologic variability of fibrinogen concentration. The quantitative comparison of analytic error, population ranges, and individual variability should permit more precise interpretation of clinical data than previously has been possible.
Normal Concentrations of Lactate, Glucose, and Protein in Cerebrospinal Fluid, and the Diagnostic Implications of Abnormal Concentrations
Authors: Pryce J D , Gant P W , Saul K J 
Published: January 2020

Abstract
Normal values for glucose, lactate, and protein in cerebrospinal fluid have been established and the relationships among them studied. Normal protein concentration is related to age. Glucose and lactate values are correlated with each other and with sex and age. By the technique of pattern appreciation, these estimations provide a useful confirmatory test for cerebrovascular accidents and for differentiating intracranial hemorrhage from other types of accident and from bloody spinal fluid taps, and they have considerable prognostic value in assessing the milder cases. They also have a restricted value in certain other conditions.
A Computer-Assisted Electrode System for Measuring Blood pH, pO2, pCO2, Sodium, and Potassium
Authors: Neff G W , Radke W A , Sambucetti C J , Widdowson G M 
Published: January 2020

Abstract
An experimental automatic electrode system was constructed to determine the feasibility of making routine determinations of blood pH, pO2, pCO2, sodium, and potassium in intensive care units. The equipment standardizes itself automatically every 25 min, and is self-cleaning after a blood specimen has been analyzed. The analyzer is connected on-line to an IBM 1800 computer on an interrupt basis. There was no significant difference between the results for pH, pO2, and pCO2 obtained with this machine and those by manual methods. The precision obtainable for the five determinations is given. The relationship between blood and plasma sodium and potassium activities determined with the glass electrodes and plasma sodium and potassium concentrations determined by flame photometry is discussed.
An Automated Fluorometric Method for Determination of Malate Dehydrogenase Activity in Serum
Authors: Schwartz P L , Burns H J 
Published: January 2020

Abstract
An automated system for the sensitive, reproducible determination of malate dehydrogenase activity in serum is described and evaluated. After incubation of serum at 25°C and double dialysis, fluorometry is used to measure the disappearance of NADH during reaction. Certain precautions are necessary to maintain the stability of NADH and oxaloacetate and to assure washout of adsorbed serum components from the system. Control serum (Enza-trol) is used as an enzyme reference material. Results from the automated method agree well with those from an independent manual method. Replicability is excellent, and results from samples stored at 4° or -20°C are essentially the same as those from fresh samples. A mean value of 36.6 ± 8.5 U of malate dehydrogenase per liter was obtained on sera from 34 healthy adults, a value that agrees well with normal values obtained by others.
Ultraviolet-Absorbing Components of Urine from Mentally Retarded Children. III
Authors: Lis Elaine W , Lis Adam W , deHackbeil Konrad F 
Published: January 2020

Abstract
Urinary excretion of ultraviolet light-absorbing end-products of metabolism was studied in mentally retarded children and a single plasma dialysate from a nephrectomized adult male. Aliquots were fractionated on Dowex-1 columns with 1 mol/liter and 4 mol/liter formic acid gradients. Resolved peaks were pooled and suitable aliquots submitted to two-dimensional ascending paper chromatography. Among previously unidentified components, 5-alkyl substituted uracil was found in the plasma dialysate obtained from the nephrectomized male. Citrullinemia was shown to be associated with a high excretion of what we believe to be orotic acid. Another familial disorder of central nervous system function complicated by mental retardation and aggressive destructive behavior (not Lesch-Nyhan syndrome) was characterized on the basis of a urinary metabolic profile. In some mentally retarded children, excretion of creatinine varied enormously. Creatinine, submitted to a systematic, quantitative procedure for assessing the behavioral and physiologic state in mice, had properties of a weak minor tranquilizer; its sedative attributes may be responsible for light sleep preconditioning.
Use of Metamizol in Determining Phospholipid Phosphorus in Serum
Authors: Guirgis Fayez K , Habib Yehia A 
Published: January 2020

Abstract
Metamizol (methampyrone) is used as the reducing agent for determination of phospholipid phosphorus in serum. The analysis, rapid and easy, yields results that agree well with those obtained by well-established procedures.
Evaluation of Light-Scattering Index (Nephelometry) for Assessing Serum Triglycerides and Lipoprotein Phenotypes
Authors: Helman Edith Zak , Blevins Eleanor J , Gleason Irene O 
Published: January 2020

Abstract
Light-scattering measurements (nephelometry) of serum after filtration through appropriate filters is a rapid method for physically determining triglyceride concentrations and lipoprotein phenotypes. A correlation coefficient of greater than 0.9 was obtained when aliquots of the same specimen were tested for triglycerides by light scattering in an Aminco-Bowman Spectrophotofluorometer and by a chemical (Van Handel and Zilversmit) method. Lipoprotein phenotyping by agarose gel electrophoresis and by light-scattering measurement corresponded excellently. In equivocal cases, nephelometric results agreed better with the triglyceride and cholesterol data than did the electrophoretic method.
Application of the Phenol—Hypochlorite Reaction to Measurement of Ammonia Concentrations in Kjeldahl Digests of Serum and Various Tissues
Authors: Shahinian Antranik H , Reinhold John G 
Published: January 2020

Abstract
Conditions have been defined that enable the use of nitroprusside as a catalyst for the phenol-hypochlorite reaction when the latter is applied to measurement of nitrogen in Kjeldahl digests containing mercury. This is accomplished by lowering the concentration of mercury to a range where it remains effective in accelerating the destruction of organic matter during digestion but no longer reacts with nitroprusside. In addition, the use of minimal concentrations of nitroprusside diminishes further the possibility of interference by mercury and has the added advantage of decreasing the pH dependence of indophenol blue formation. The sensitivity of the reaction makes possible measurement of nitrogen in very small samples with relatively short digestion times.
Abnormal Concentrations of Nickel in Serum in Cases of Myocardial Infarction, Stroke, Burns, Hepatic Cirrhosis, and Uremia
Authors: McNeely Michael D , Sunderman F William , Nechay Maria W , Levine Howard 
Published: January 2020

Abstract
Nickel concentrations were measured by atomic absorption spectrometry in sera. The mean concentration of nickel in sera of 47 healthy adults was 2.6 SD ± 0.8) µg/liter. Abnormally high mean concentrations (µg/liter) of serum nickel were found in patients with: (a) acute myocardial infarction (13-36 h after onset), mean = 5.2 ± 2.8, N = 33, P &lt;0.001; (b) acute stroke (37-72 h after onset), mean = 4.5, N = 12, P &lt;0.005; and (c) acute burns (&gt;25% body surface, 37-72 h after injury), mean = 7.2, N = 3, range = 4.1-10.9. Diminished mean concentrations of serum nickel were found in patients with: (a) hepatic cirrhosis, mean = 1.6 ± 0.8, N = 18, P &lt;0.005; and (b) chronic uremia, mean = 1.7 ± 0.7, N = 12, P = &lt;0.005. Normal mean concentrations of serum nickel were found in patients with: (a) acute myocardial ischemia without infarction (13-36 h after onset), mean = 3.3 ± 1.6, N = 22; (b) acute trauma with fractured bones (13-36 h after injury), mean = 2.7 ± 0.9, N = 19; (c) acute delirium tremens (13-36 h after admission), mean = 2.3 ± 0.9, N = 25; and (d) muscular dystrophy, mean = 2.3 ± 1.4, N = 10. In sera collected from 12 mothers immediately after normal delivery, the mean concentration of nickel was 3.0 ± 1.2 µg/liter, the same values as for sera from the umbilical cords of their 12 full-term infants.
Automated Procedure for Determination of Bilirubin in Human Sera
Authors: Cooper J D H 
Published: January 2020

Abstract
An automated procedure is presented, based on the method of Bruchner [Amer. J. Clin. Pathol. 32, 513 (1959)], for determination of both total and conjugated bilirubin. The method is standardized by use of bilirubin in human serum, which is stabilized by a mixture of formamide and cyanide. Hemoglobin does not interfere at concentrations less than 500 mg/100 ml, and the effect of lipemia is minimized.
A Digital pH Stat for Automated Kinetic Analysis
Authors: Karcher Raymond E , Pardue Harry L 
Published: January 2020

Abstract
A "pH stat" that spectrophotometrically monitors pH and electrolytically generates either acid or base has been developed to follow the rates of certain enzyme-catalyzed reactions. The pH is monitored by coupling a pH indicator to the main reaction. As reaction proceeds, the instrument coulometrically pulses titrant into the photometer cell as required to maintain a constant pH. Generation is accomplished with Pt and Ag-AgCl electrodes. Constant-current conditions are used so that a given number of pulses corresponds to a constant reaction interval. A series of flip-flops counts the pulses as they occur; a timing circuit records the time required to generate a set number of pulses. A reciprocal time computer provides automated readout in units of absolute enzyme activity. Initial experiments on the acetylcholinesterase system (pH 7.60) show linear enzyme dependence curves with scatter of 2% or less. The change in pH during a single cycle is less than 0.05 units and the precision for replicate samples is about 2%.
Influence of Statistical Method Used on the Resulting Estimate of Normal Range
Authors: Reed Allen H , Henry Richard J , Mason William B 
Published: January 2020

Abstract
The choice of statistical method can greatly influence the calculated normal range apart from any biological or chemical considerations. Nonparametric normal range estimates are, for practical purposes, as accurate as estimates that assume the distribution of data to be gaussian or loggaussian when the distribution assumed is true. When data are not distributed as assumed, nonparametric estimates are more accurate.
An Automated, Fluorometric Procedure for Determining Serum Lipase
Authors: Fleisher Martin , Schwartz Morton K 
Published: January 2020

Abstract
Currently available routine assays for lipase (glycerol ester hydrolase EC 3.1.1.3) are lengthy and laborious, and may utilize nonspecific substrates. An automated continuous-flow procedure has been developed for the fluorometric determination of serum lipase activity. This involves the use of a fluorescein fatty acid ester, monodecanoyl fluorescein (MDF), as substrate. This compound is not fluorescent, but one of its hydrolytic products, fluorescein, is intensely fluorochromatic. Under the conditions of the assay, in which 0.5 mmol of MDF is used per liter, the hydrolysis is linear with time and follows zero-order kinetics through the hydrolysis of at least 35% of the substrate. Determinations are carried out on 0.1 ml serum at the rate of 60 assays/hour. By this assay, mean activity in the serum of normal persons is 751 units (SD, 38 units).
A More Sensitive Spectrophotometric Method for Determination of Isoniazid in Serum or Plasma
Authors: Eidus Leslie , Harnanansingh Anita M T 
Published: January 2020

Abstract
A sensitive spectrophotometric method is described for determining isoniazid in serum or plasma. It is extracted from biological fluids by a mixture of organic solvents and re-extracted into hydrochloric acid. In this medium, isoniazid reacts with trans-cinnamaldehyde to form a derivative absorbing maximally at 340 nm. The method is five times more sensitive than published procedures in which vanillin or piperonal is used as coupling reagent for the estimation of isoniazid.
Antibodies to Testosterone-3-Bovine Serum Albumin, Applied to Assay of Serum 17β-ol Androgens
Authors: Chen Jeffrey C , Zorn Elinor M , Hallberg Marvin C , Wieland Ralph G 
Published: January 2020

Abstract
Testosterone was conjugated to bovine serum albumin at carbon 3, and antibodies to this conjugate were developed in virgin female rabbits. This antiserum, diluted 1:3200, was used to measure testosterone. With tritiated testosterone and anti-rabbit γ-globulin as the second antibody, a doseresponse curve was obtained for doses in the range 0.1-10 ng. The antibody cross-reacts extensively with dihydrotestosterone, so that dihydrotestosterone is measured with testosterone in extracted but unchromatographed serum. Results for pooled serum from men, as measured repeatedly by radioimmunoassay and competitive binding assay for testosterone, agreed well. Seventeen normal men had serum 17β-ol androgen concentrations of 667 ng/100 ml (SD, ±248); seventeen normal, menstruating women had a mean concentration of 69 ng/100 ml (SD, ±18). Values for 17β-ol androgens in adolescent males agreed reasonably with testosterone values reported by other investigators. Values are presented for patients with various androgenic disorders. This procedure is easy; many samples can be processed at one time.
Modified Semiautomated Method for Serum Thyroxine
Authors: Yee Hugh Y , Bowdell Judy , Jackson Bobette 
Published: January 2020

Abstract
A modified semiautomated technique is described for serum thyroxine. The AutoAnalyzer system used is both sensitive and "noise" free. Two screening steps are presented that minimize possible contamination of the AutoAnalyzer system. Sampling rate is 50/h and 1 ml of serum is required.
A Reliable Spot Test for Mucopolysaccharidoses
Authors: Berman E R , Vered J , Bach G 
Published: January 2020

Abstract
A new spot test for detecting excessive excretion of mucopolysaccharides in urine has been used with a group of 17 patients. Reliability of the test was evaluated by correlating clinical findings with qualitative and quantitative analyses of urinary mucopolysaccharides. Normal controls, with 3.8 to 10.0 mg of uronic acid in this form per liter of urine, gave negative spot tests; all cases of clinically diagnosed mucopolysaccharidoses (MPS) I, II, and III (Hurler’s, Hunter’s, and Sanfilippo’s syndromes, respectively) gave strongly positive ones. Two patients (female siblings) with Morquio’s syndrome (MPS IV) also gave positive spot tests, which were somewhat less intense than those given by patients with MPS I, II, or III. The test for Morquio’s syndrome, positive with fresh urine, was essentially negative with samples at -26°C for three months or longer. A group of seven patients having various degrees of skeletal deformities, mental retardation, dwarfism, or corneal opacities, but not fitting the presently accepted classification of mucopolysaccharidoses, gave negative spot tests, and chemical analyses of their urinary mucopolysaccharides showed normal patterns of excretion.
An AutoAnalyzer Procedure for Serum Iron and Total Iron-Binding Capacity, with Use of Ferrozine
Authors: Yee Hugh Y , Zin Anastasia 
Published: January 2020

Abstract
An AutoAnalyzer method has been developed in which the recently introduced reagent for iron, 3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine ("ferrozine"), is used. With the Technicon colorimeter or Gilford 300-N spectrophotometer in use, sampling rates may be 30/h or 50/h, respectively. Sample volume is 0.8 ml, and measurements are made at 560 nm. A procedure for measuring total iron-binding capacity is also described.
Automated Procedure for Assay of 2,3-Diphosphoglycerate in Red Cells by Measuring Enzymatically Released Inorganic Phosphorus
Authors: Powell James B , Emery Clarence E , Peyton Gaylon A 
Published: January 2020

Abstract
An automated technique is reported for measuring erythrocyte 2,3-diphosphoglycerate (DPG). We have automated a specific method, in which the DPG phosphatase activity of phosphoglycerate mutase is used and potentiated by phosphoglycolate. Precision, accuracy, recovery, and comparability with a reference method are discussed.
Automated Quantitative Immunochemical Analysis of Human Immunoglobulins
Authors: Markowitz Harold , Tschida A R 
Published: January 2020

Abstract
A commercial automated continuous-flow procedure for estimating specific serum proteins has been evaluated for use in determination of IgG, IgA, IgM (both 19S and 7S), α1-antitrypsin, and cerebrospinal fluid proteins. Results of the automated procedure correlate well with manual methods, but are much more precise. Estimation of 7S IgM by the automated method is more accurate than estimation by radial immunodiffusion, because concentrations of 7S IgM are not spuriously elevated.
Simple, Rapid, Kinetic Method for Serum Creatinine Measurement
Authors: Lustgarten Jack A , Wenk Robert E 
Published: January 2020

Abstract
A study of the reaction between creatinine and alkaline picrate confirmed that there is a linear relation between absorbance change and creatinine concentration over the entire clinical range of values. The specificity and accuracy of the method are comparable to that of the end-point Jaffé reaction with deproteinization. The test is somewhat imprecise in the low range, but the simple, rapid procedure is appropriate for the monitoring of patients with glomerular disease and those undergoing therapeutic dialysis.
Simple Method for Determination of Urinary δ-Aminolevulinic Acid as an Index of Lead Exposure
Authors: Tomokuni Katsumaro , Ogata Masana 
Published: January 2020

Abstract
A simple method is described for the quantitative analysis of urinary δ-aminolevulinic acid. 2-Methyl3-carbethoxy-4-(3-propionic acid) pyrrole, produced by the condensation of δ-aminolevulinic acid with ethyl acetoacetate, is almost completely extracted from an aqueous solution with ethyl acetate without resorting to ion-exchange column chromatography. The pyrrole is determined colorimetrically by treating an aliquot of the extract with a modified Ehrlich’s reagent.
Effects of Various Medications on Values from the HABA and BCG Methods for Determining Albumin
Authors: Notrica Solomon , Miyada Don S , Baysinger Vern , Nakamura Robert M 
Published: January 2020

Abstract
We investigated the effects of acetylsalicylic acid, salicylic acid, sulfisoxazole, and phenobarbital—at concentrations at or just above those in serum after therapy—on results of the 2-(4'-hydroxyazobenzene) benzoic acid (HABA) and bromcresol green (BCG) methods for measuring serum albumin. Although the HABA method was more prone to such interference, only interference by salicylic acid with the HABA method is significant. Salicylic acid at a concentration of 400 mg/liter decreases the apparent values for HABA-albumin by about 10%.