bluuebunny/crossref_metadata_2025_split huggingface dataset:
β-Glycerophosphate and Thymolphthalein Monophosphate Compared as Substrates for Determining Alkaline Phosphatase Activity in Serum
Authors: Dalal Fram R , Akhtar Mohammed , Shin Kwang Hi , Winsten Seymour 
Published: January 2020

Abstract
β-Glycerophosphate and sodium thymolphthalein monophosphate were compared clinically and methodologically as substrates for alkaline phosphatase assay. The relative simplicity of the thymolphthalein procedure, its adaptability to semi-automated and micro methods, and its apparent clinical reliability indicate that it is a better substrate for serum alkaline phosphatase assay than is β-glycerophosphate.
Automated Immunoprecipitin Technique for Analysis of the Third Component of Complement (C'3) in Human Serum
Authors: Killingsworth L M , Savory John , Teague Perry O 
Published: January 2020

Abstract
An automated continuous-flow procedure has been developed for measuring C'3 in human serum, by reaction with specific antiserum. The procedure is standardized with pooled human serum, appropriate dilutions of which had previously been measured for C'3 by a reference method. C'3 values obtained by this new automated procedure correlate with values obtained by radial immunodiffusion. The precision (CV) of this method is 1.65%.
Micromethod for Measuring Pentoses by Use of an Aniline Reagent
Authors: Goodwin Jesse F 
Published: January 2020

Abstract
Aniline, in an acetic acid solution containing borate and thiourea, reacts with pentose sugars to yield a highly colored chromogen that absorbs maximally at 480 nm. The reagent may be used to measure pentoses in dilute protein solutions and serum without first removing protein. Bilirubin and hemoglobin do not interfere extensively with the method, but this interference is substantially decreased if a protein-free filtrate is used. An optimal procedure is presented for the measurement of pentoses in the presence of glucose, involving use of glucose oxidase and the aniline reagent. The method is easy to perform, sensitive, and reproducible.
Determination of Serum Ionic Calcium with an Ion-Selective Electrode: Evaluation of Methodology and Normal Values
Authors: Li Ting-Kai , Piechocki Joseph T 
Published: January 2020

Abstract
Ionized calcium in serum has been determined potentiometrically by using a calcium ion-selective electrode in a flow-through configuration. For 397 normal human adults the mean value for serum ionic calcium was 1.22 ± 0.09 (2 SD) mmol/liter. Factors affecting the measurement—such as the procedure for sample collection, sample storage, the preparation of standard solutions, the type of resin employed, and the choice of the reference electrode filling solution—were examined. Magnesium ions in physiological concentrations cause a slight depression of the electrode's response to calcium ions, indicating an interference by magnesium in the method. Under the conditions used, the relative standard deviation (CV) of the method is 0.8%.
Varieties of Human Serum Lipoprotein Pattern: Evaluation by Agarose Gel Electrophoresis
Authors: Papadopoulos N M , Kintzios J A 
Published: January 2020

Abstract
A previously reported agarose gel electrophoretic technique for the determination of serum lipoprotein patterns has been modified for analysis of a large number of samples for screening and epidemiological purposes. In addition, we demonstrate the varieties of lipoprotein patterns that can clearly be distinguished and visually evaluated for practical applications in the clinical laboratory.
Trace-Element Analysis in Clinical Chemistry
Authors: Schroeder Henry A , Nason Alexis P 
Published: January 2020

Abstract
Present knowledge of human bodily contents and concentrations in blood, urine, and hair of 11 essential trace elements and 17-22 nonessential inert or toxic trace elements is reviewed and summarized. Analyses of trace elements are applicable as diagnostic aids and indices for therapy in a number of clinical conditions. Techniques are not difficult, and analyses will probably become more or less routine for many diseases in which primary or secondary abnormalities are manifest. Trace elements play fundamental roles in human metabolism.
Rapid Automated Analyses Performed in Parallel
Authors: Hatcher D W 
Published: January 2020

Abstract
The analytical concept of monitoring chemical reactions simultaneously in a number of discrete samples is explored. A new class of analyzers based on this concept has been introduced. One such system uses centrifugal force to transfer and mix reagent and sample in a multiple-cuvet rotor. A second, completely new system (CHAMP) is introduced here. In both systems, data signals can be generated at 3.3-ms intervals. Thus, these devices are potentially very fast and can be interfaced directly with a computer, which facilitates their integration into computerized information systems of hospitals.
Rapid, Reliable Method for Measuring Serum Lipase Activity
Authors: Yang Jeun-Sing , Biggs H G 
Published: January 2020

Abstract
The method of Dirstine et al. [Clin. Chem. 14, 1097 (1968)] has been modified to increase sensitivity and decrease manipulations. The modifications permit a 10-min incubation, and a single analysis can be completed in 30 min, or five concomitant assays can be done in an hour. Stability of the substrate has been increased by increasing the emulsifier concentration. Recovery of the fatty acid products has been improved by adding electrolyte to the copper reagent and by using combined organic solvents. Pancreatin was added to human serum to provide samples with increased activities, with behavior identical to that of pathological sera with increased lipase activities. Normal values for 100 adults, 50 women and 50 men, ranged between 21 and 171 units, with a mean of 63 units. Within-day precision for 21 assays (mean activity, 641 units) was ±16 units (SD). Between-days precision for 36 assays was ±18 units (SD), with a mean of 636 units.
Automated Colorimetric Method for Estimating Serum Triglycerides
Authors: McLellan G H 
Published: January 2020

Abstract
A colorimetric adaptation of the fluorometric method of Noble and Campbell is described. Decreased sensitivity, caused by substituting colorimetry for fluorometry, has been improved by increasing the proportion of serum to isopropanol extraction fluid from 1 in 21 to 1 in 11, and by placing an adjustable range expander between colorimeter and recorder. This accurate and reliable adaptation has obviated the need for an expensive fluorometer.
Rapid Identification and Quantitative Determination of Barbiturates and Glutethimide in Blood by Gas—Liquid Chromatography
Authors: MacGee Joseph 
Published: January 2020

Abstract
Barbiturates and glutethimide can be identified and measured in whole blood, plasma, or serum in 20 min. An internal standard containing known amounts of five common barbiturates is added to the sample, the sample is acidified, and the sedatives are extracted rapidly into toluene, then from the toluene into a small volume of aqueous tetraethylammonium hydroxide. An aliquot of this last extract is introduced directly into the gas chromatograph, where the barbiturates are converted to their ethyl derivatives and separated on a silicone column. They are identified by observing which of the internal standard peaks has increased and measured by measuring the extent of increase. Glutethimide can be determined on the same chromatogram. Mephobarbital and phenobarbital can be simultaneously determined.
Profile of Volatile Metabolites in Human Urine
Authors: Zlatkis Albert , Liebich Hartmut M 
Published: January 2020

Abstract
Volatile constituents of 30 urines from 10 adults have been studied by gas chromatography, and two also by mass spectrometry. The sample was prepared by extracting urine with ethyl ether, distilling the extract at low temperature under reduced pressure, and concentrating the distillate to a few microliters. High-efficiency capillary columns, 150 m x 0.5 mm i.d., provide the resolution necessary to indicate the presence of some 300 compounds, 40 of which have been identified by mass spectrometry. These include ketones, alcohols, lactones, terpenes, furans, dimethyl sulfone, pyrrole, and allyl isothiocyanate. Dietary changes have a relatively small effect on the profile of the volatiles, and interindividual patterns are very similar. These facts make analyses of this kind of potential diagnostic use.
Instrument Design Considerations and Clinical Applications of Stable Isotope Analysis
Authors: Klein Peter D , Haumann Joseph R , Eisler William J 
Published: January 2020

Abstract
Stable isotope analysis by gas chromatography-mass spectroscopy-accelerating voltage alternation (GMA) is a new concept, which makes it possible to eliminate radiological hazard from clinical tracer studies. To become useful to, and used by, the clinician, this instrumentation must eventually become competitive with that for liquid scintillation counting from the standpoint of sample size, sensitivity, automation, routine operation, and cost. A second-generation instrument, recently constructed in the Division of Biological and Medical Research at Argonne National Laboratory, has been put into operation and is being used in collaborative clinical studies conducted at the Mayo Clinic. The design features and operating characteristics of this system are discussed with reference to the ultimate clinical requirements.
Influence of a Chemically Defined Diet on the Composition of Serum and Urine
Authors: Young D S , Epley Jean A , Goldman Peter 
Published: January 2020

Abstract
We have studied the effects of ingestion of a chemically defined diet on the constituents of serum and urine of five normal volunteers. The diet, believed to meet all human nutritional requirements, caused a decrease in serum cholesterol and urea nitrogen and an increase in serum phosphate, uric acid, and creatinine. Urinary creatinine is unchanged from that of a random diet but urinary electrolytes, urea, and uric acid decrease to a new stable value, which is achieved after four days. High-resolution techniques have been used to measure the carbohydrate-containing constituents of urine and those that can be detected by their ultraviolet absorbance or their reaction with ninhydrin. A considerable decrease in the number of these urinary constituents is effected by the chemical diet within four days, but even by this time all compounds attributable to the random diet may not have been completely eliminated. Many urinary components that persist while the subjects are on the simplified diet have been tentatively identified.
Changes in the Saccharoid Fraction in Rats with Alloxan-Induced Diabetes or Injected with Epinephrine
Authors: Alam M Jafar , Rahman M Ataur 
Published: January 2020

Abstract
"Saccharoid fraction," defined as the nonglucose reducing substances in blood, increases both in hyperglycemia (blood glucose concentration exceeding 280 mg/dl) and hypoglycemia (blood sugar less than 65 mg/dl) in rats. This increase is not completely accounted for by glutathione, glucuronic acid, ascorbic acid, uric acid, and creatinine. Some of the constituents of saccharoid fraction seem to be insulin-sensitive. Alloxan not only produces diabetes in rats but also increases blood glucuronic acid, ascorbic acid, and uric acid. Estimated constituents of saccharoid fraction account for only 45% to 75% of the saccharoid fraction. The unaccounted-for saccharoid fraction shows changes similar to those in the accounted-for saccharoid fraction, in the diabetic rats, as was also the case after treatment with insulin of normal or diabetic animals. The fraction not accounted for by the estimated constituents may represent the reducing sugar phosphates present in the blood.
A Simplified Radioimmunoassay for Human Pituitary Luteinizing Hormone in Serum
Authors: Levine Robert A , Donabedian Richard K , Sobrinho Luis G 
Published: January 2020

Abstract
A simplified radioimmunoassay is described for human pituitary luteinizing hormone (LH). The principal modification over existing methods is that talc is used to separate antibody-bound hormone from free hormone by adsorption of the latter. Serum concentrations of LH in normal males, ovulatory females (follicular phase), postmenopausal females, patients with primary gonadal failure, and patients with hypopituitarism averaged 4.7, 4.6, 26.4, 30.8, and 1.9 µg of reference std. LER 907 per 100 ml of serum, respectively (10.3, 10.1, 57.8, 67.5, 4.2 milli-int. units/ml, respectively). These values are consistent with the clinical diagnoses.
Manual and Automated Determination of Immunoglobulins in Unconcentrated Cerebrospinal Fluid
Authors: Savory J , Heintges M G , Killingsworth L M , Potter J M 
Published: January 2020

Abstract
Manual procedures have been developed for determination in human cerebrospinal fluid of the immunoglobulins IgG, IgA, and IgM. An automated continuous-flow procedure for determination of IgG in human CSF is also described. The immunoglobulins are quantitated in both cases by immunoprecipitin reactions, with use of commercial antiserum. Values determined for the immunoglobulins by the manual method correlate with values for gamma globulin obtained by electrophoresis. The values for IgG from the manual method also correlate with IgG values determined by the automated procedure. The precision of duplicate determinations with the manual procedures for IgG, IgA, and IgM is 3.4, 1.8, and 1.0% (relative standard deviation), respectively, and that for lgG with the automated system is 3.48%.
Estimation of Normal Ranges from a Controlled Sample Survey. I. Sexand Age-Related Influence on the SMA 12/60 Screening Group of Tests
Authors: Reed A H , Cannon D C , Winkelman J W , Bhasin Y P , Henry R J , Pileggi V J 
Published: January 2020

Abstract
A panel of 13 clinical chemical tests was performed on sera from 1419 clinically normal adults, utilizing the SMA 12/60 AutoAnalyzer, to obtain practical normal range estimates by nonparametric statistical methods. Serum samples were obtained over a period of 14 months from eight geographic areas of the United States. Normal range estimates are derived for the entire group surveyed, for subgroups of males and females, and for various age categories within each of the two subgroups. For each panel test, sexand age-related variation is assessed by using nonparametric statistical tests for identity of normal-range endpoints. Derived normal ranges that are practical for clinical laboratory usage are proposed. Finally, a measure of validity of our estimates of normal range is applied.
Clinical Nephelometry: 1. New, Accurate, Heat-Precipitation Nephelometric Method for Rapid Determination of Plasma Fibrinogen
Authors: Rice Eugene W , Muesse D E R 
Published: January 2020

Abstract
We have developed an accurate procedure for measurement of plasma fibrinogen. Turbidity resulting from heating (56°C, 20 min) plasma diluted with a new "zwitterionic" buffered-saline reagent (pH 5.6) is nephelometrically measured (600 nm). We evaluated the method both by confirming the accuracy of its prestandardization and calibration on a new clinical nephelometer, and by comparative standardization by use of a conventional spectrophotometer. The nephelometer is more sensitive and gives a linear response over a wide range of concentrations. Representative information supporting the broad clinical utility of the determination of plasma fibrinogen is illustrated. These assays should be a significant complement to muititest biochemical screening of both healthy and hospitalized individuals.
Screening of 563 Students for Cholinesterase Variants
Authors: Becker Charles E 
Published: January 2020

Abstract
Of 563 dental students screened for cholinesterase variants, 97.2% were homozygotes for the usual cholinesterase (E1uE1u), 2.1% were heterozygotes for the usual and the dibucaine-resistant cholinesterases (E1uE1a), and 0.7% were heterozygotes for the usual and the fluoride-resistant cholinesterases (E1uE1f).
Rapid Analysis for Total Mercury in Urine and Plasma by Flameless Atomic Absorption Analysis
Authors: Kubasik Norman P , Sine H E , Volosin Michael T 
Published: January 2020

Abstract
A rapid, simplified method is described for analysis for total mercury in urine and plasma. A sulfuric acid—potassium permanganate digestion of small sample volumes efficiently prepares them for measurement of both organic and inorganic mercury, which can be done at the rate of about 100 samples per hour.
Haptoglobin Phenotype Frequencies in Mentally Retarded Persons
Authors: Rundle A T , Clothier B , Sudell Barbara 
Published: January 2020

Abstract
Haptoglobin phenotype frequencies for 887 unselected mentally retarded patients were within the range reported for normal European populations. Of these sera, 2% initially classified as anhaptoglobinemic by subjective appraisal of starch-gel electropherograms were subsequently shown to be hypohaptoglobinemic. This frequency of hypohaptoglobinemia is similar to that reported for normal populations. Sixteen of the hypohaptoglobinemic cases were reinvestigated, and all but one showed some evidence of hepatic dysfunction.
Biological Applications of the Carbon Rod Atomizer in Atomic Absorption Spectroscopy. 2. Determination of Copper in Small Samples of Tissue
Authors: Stevens Brian J 
Published: January 2020

Abstract
A simple technique is presented for the analysis for copper in small fragments of tissue. Dissolution of the tissue in concentrated nitric acid is the only preparative step required. Copper content is then determined by comparison with standards, by using the carbon rod atomizer previously described. Sample volumes of less than 2 µl are used for each measurement. The method gives results that compare well with both colorimetric and flame atomic absorption methods, and also with neutron activation analysis, and appears to be applicable to the analysis of other metals in tissue.
Manual Spectrophotometric and Fluorometric Determination of Tocopherol in Cerebrospinal Fluid
Authors: Vatassery G T , Mortenson G A 
Published: January 2020

Abstract
Methods are reported for the manual spectrophotometric or fluorometric estimation of tocopherol in human cerebrospinal fluid. The fluid is centrifuged, an equal volume of ethanol is added, and the tocopherol is extracted with hexane, which is then used for the direct estimation by fluorometry. The fluorescence of tocopherol is significantly affected by the proportion of ethanol in the hexane solvent. The standards used for comparison should therefore be dissolved in hexane that had been previously equilibrated with twice its volume of ethanol:water (1:1 by vol). For spectrophotometry, the original hexane extract is dried at 40°C under reduced pressure, the residue dissolved in hexane, and color developed by adding bathophenanthroline, ferric chloride, and orthophosphoric acid. The color is measured at 536 nm. Concentrations of tocopherol in the spinal fluid samples analyzed so far ranged from 40 to 210 µg/ liter.
Isolation and Measurement of Pancreatic Amylase in Human Serum and Urine
Authors: Fridhandler L , Berk J Edward , Ueda M 
Published: January 2020

Abstract
We describe a sensitive quantitative procedure for separating isoamylases in human serum, urine, and tissue homogenates. Two components have been discerned with chromatographic characteristics resembling those of pancreatic and salivary amylases, respectively. Several lines of evidence—derived from studies in normal subjects, pancreatectomized patients, and patients with acute pancreatitis—indicate that the pancreas is probably the source of the component in serum and urine that exhibits characteristics of pancreatic amylase. The source of the component resembling salivary amylase has not yet been fully defined. Isoamylase analysis of extracts of fallopian tube and liver revealed two amylase components with chromatographic properties similar to pancreatic and salivary amylases, respectively.
Simple Automated Spectrophotometric Method for Assay of Trypsin and Chymotrypsin in Duodenal Juice
Authors: Vandermeers A , Vandermeers-Piret M-C , Rathé J , Christophe J 
Published: January 2020

Abstract
Trypsin and chymotrypsin were automatically assayed by a simple spectrophotometric method, with specific ester derivatives as substrates. Samples containing 0.25 to 2.5 enzyme units in 0.5 ml were analyzed at a rate of 40 to 60 assays per hour, each sample being incubated for 6 min. The acidity developed during esterolysis was measured, with phenol red as the acid—base indicator. The full-scale deflection of the recorder, corresponding to 0.5 absorbance at 420 nm, was obtained with a sample containing 5 U of enzyme per milliliter, incubated in Tris-HCl buffer (25 mmol/liter, pH 8.0), in the presence of phenol red (124 µmol/liter). This variation corresponded to a decrease of 0.4 pH unit.
Effect of Some Drugs on Clinical Laboratory Values as Determined by the Technicon SMA 12/60
Authors: Singh H P , Hebert M A , Gault M H 
Published: January 2020

Abstract
We examined the quantitative in vitro effects of 45 drugs on 12 automated biochemical laboratory tests done on the Technicon SMA 12/60. Of these, 25 drugs in 1 mmol/liter concentration interfered in one or more of the assays. However, only eight drugs (N-acetyl-p-aminophenol, p-aminosalicylate, isoniazid, L-dopa, α-methyldopa, 6-mercaptopurine, sulfathiazole, and ascorbic acid) reacted positively with the test reagents at concentrations likely to occur in plasma after administration of maximum single therapeutic doses. A slight false elevation of plasma uric acid and a major false increase in urine values occurred in patients after ingestion of N-acetyl-p-aminophenol and phenacetin, corresponding to the greater concentrations of these drugs and their metabolites in urine. The relative importance of various factors affecting the influence of drugs on biochemical test values is discussed.
Rapid Large-Scale Screening of Blood Proteins by Use of Cellulose Acetate Electrophoresis on a Solid Support
Authors: Nerenberg Samuel T , DeMarco Linda , Ganger Carolyn 
Published: January 2020

Abstract
We describe a new principle of cellulose acetate electrophoresis (solid-support electrophoresis), in which cellulose acetate membranes are given a solid support, instead of being suspended as heretofore. The new technique is particularly well suited for screening procedures, because many samples can be processed economically on a single run. Also described for the first time, in conjunction with solid-support electrophoresis, is a method of (a) simultaneously using continuous and discontinuous buffer systems with specially (series) oriented membranes, or (b) a single-sample application for fractionating different constituents simultaneously (proteins, lipoproteins, isoenzymes, etc.).
Tyrosinemia Induced by a Pyridoxine Antagonist, Desoxypyridoxine
Authors: Easton E Joanne , Simpson Ian , Martin J Kenneth , Campbell Donald J 
Published: January 2020

Abstract
Tyrosinemia was produced in Wistar rats by feeding a diet deficient in vitamin B6, and containing 1 mg of 4-desoxypyridoxine (DOP) per 100 g of diet. Concentrations of serum tyrosine were greatest in lactating rats, with smaller increases in nonpregnant, nonlactating females and adult males. Paper chromatography of urine indicated that DOP feeding also probably inhibits formation of most normal urinary metabolites of tyrosine. Livers of several rats showed no evidence of cirrhosis after 18 days on the diet containing DOP, indicating that this experimentally produced tyrosinemia is not a true model of tyrosinosis.
Single Radial Immunodiffusion of Undiluted Serum Proteins
Authors: Pizzolato M C B , Pizzolato M A , Agostoni A 
Published: January 2020

Abstract
A simple method is described for quantitative determination of IgG, IgA, IgM, α2M, and other proteins without dilution of the sample. Strips of gelatinized cellulose acetate spread with antiserum are used as a supporting medium. The method is accurate, highly reproducible, and seems particularly suitable for routine work because it permits determination of hypo-, normal, and hyperglobulinemia on a single strip.