Showing papers by "Hokkaido University published in 1973"
TL;DR: The frequency and variability of discharges of motor units in abductor digiti minimi muscle of 11 human subjects were investigated; at contractions with larger steady tension the discharge frequency of units was found to be higher and irregularity of discharge was enhanced.
163 citations
162 citations
TL;DR: Five oxidation states of horseradish peroxidase, ferrous, ferric, Compounds I and II, oxy-ferrous, are known.
Abstract: Five oxidation states of horseradish peroxidase, ferrous, ferric, Compounds I and II, oxy-ferrous, are known. Various reactions and plausible structures of these states are reported. Mechanisms of peroxidase-oxidase reactions are discussed in terms of the five oxidation states of the enzyme.
160 citations
TL;DR: The results suggest that the difference spectrum of TNP-ATP due to the interaction with heavy meromyosin arises not only from the binding of the chromophoric portion of the TNP -ATP molecule but also from that of the phosphate portion.
156 citations
TL;DR: Application of this technique to other mammalian species strongly indicated that the N-band-positive sites coincide with nucleolus organisers, and in rat kangaroo chromosomes, the N bands appeared exclusively in the nucleolu organisers.
Abstract: THE in situ DNA-RNA hybridisation techniques to locate a certain genome fraction with unique nucleotide sequences1–6 have assigned ribosomal cistrons to the satellites of human D and G group chromosomes4,5. This is of particular interest because the satellites organise nucleoli in somatic7 and meiotic cells8–10. During the course of study on the Giemsa banding mechanism (unpublished) we found that the satellite bodies of human acrocentrics can be differentially stained with Giemsa after simple procedures including extraction of both nucleic acids and histones. The staining profile, herein referred to as ‘N band’, differed clearly from the Quinacrine, Giemsa, Reversed-Giemsa, Centromeric, or Giemsa 11 banding patterns11,12. In rat kangaroo chromosomes, the N bands appeared exclusively in the nucleolus organisers13,14, that is, in the secondary constriction of the X chromosome. Further application of this technique to other mammalian species strongly indicated that the N-band-positive sites coincide with nucleolus organisers.
137 citations
TL;DR: The recruitment of motor units during voluntary isometric contraction was studied in the abductor digiti minimi muscle of 13 human subjects trained to increase tension in this muscle almost linearly from zero to maximum.
114 citations
01 Mar 1973
TL;DR: The composition of the anodic passive oxide film on iron in neutral solution has been investigated by cathodic reduction, chemical analysis and ellipsometry as mentioned in this paper, and it was found that the film retains nearly constant thickness above a critical potential where transpassive dissolution begins to occur.
Abstract: The composition of the anodic passive oxide film on iron in neutral solution has been investigated by cathodic reduction, chemical analysis and ellipsometry. The cathodic reduction using a borate solution of pH 6·35 containing arsenic trioxide as inhibitor estimates iron in the film to be all iron (III), indicating that no magnetite layer is present. Oxygen in the film is estimated from the ellipsometric thickness to be in excess of the stoichiometric ferric oxide, suggesting the presence of bound water. The average composition is represented as Fe2O3.0·4H2O, in which hydrogen may be replaced partly with iron-ion vacancy. The anodic oxide film is composed of an inner anhydrous ferric oxide layer, which thickens with the potential and an outer layer of hydrous ferric oxide whose thickness depends on the condition of passivation and environment.
The anodic oxide film formed in the oxygen-potential region has also been measured by cathodic reduction, and it is found that the film retains nearly constant thickness above a critical potential where transpassive dissolution begins to occur.
106 citations
TL;DR: The overal kinetic study of the inhibition by superoxide dismutase of the oxygen-mediated reduction of cytochrome c in the xanthine oxidase reaction showed that the catalytic reaction of superoxide Dismutase was first order with respect to enzyme and to substrate.
101 citations
TL;DR: Analysis by dinitrophenylation techniques revealed the occurrence of significant amounts of glucosamine residues with free amino groups in the peptidoglycan component of cell walls isolated from Bacillus cereus, Bacillus subtilis, and Bacillus megaterium to account for the resistance of these cell walls to lysozyme.
Abstract: Analysis by dinitrophenylation techniques revealed the occurrence of significant amounts of glucosamine residues with free amino groups in the peptidoglycan component of cell walls isolated from Bacillus cereus, Bacillus subtilis, and Bacillus megaterium. A close correlation was demonstrated between the content of N-unacetylated glucosamine residues in the peptidoglycan component and the resistance of the cell walls to lysozyme. These lysozyme-resistant cell walls and peptidoglycan were converted into a lysozyme-sensitive form by means of N-acetylation with acetic anhydride. Thus, the occurrence of the N-unacetylated glucosamine residues in the peptidoglycan component accounts for the resistance of these cell walls to lysozyme. The N-unacetylated glucosamine residues were not found in a significant amount in the cell walls of Micrococcus lysodeikticus, Staphylococcus aureus, Streptococcus faecalis, Lactobacillus casei, or Lactobacillus arabinosus.
89 citations
TL;DR: In this article, it was shown that the quautum theory of gravity can be a zero-slope limit of the generalized Virasoro model where the Regge intercept is fixed at two.
Abstract: It is demonstrated that the quautum theory of gravity can be a zero- slope limit of the generalized Virasoro model where the Regge intercept is fixed at two. The quautum theory of gravity is taken to mean Gupta-Feynman's perturbation on the flat background. The correspondence for the graviton Compton scattering is demonstrated by direct calculations. (LBS)
88 citations
TL;DR: In this paper, the dynamic mechanical moduli of slightly (0.16wt%) plasticized poly(vinyl chloride) were measured by the method of free damped oscillation in the temperature range from −180 to +100°C.
Abstract: The dynamic mechanical moduli of slightly (0—16wt%) plasticized poly(vinyl chloride) were measured by the method of free damped oscillation in the temperature range from −180 to +100°C. The added plasticizers are tricresyl phosphate (TCP), butyl benzyl phthalate (BBP), dioctyl phthalate (DOP), dibutyl sebacate (DBS) and dioctyl sebacate (DOS). Two dispersion regions (α and β) are observed in the case of poly(vinyl chloride) and they are influenced by addition of plasticizers. The α-dispersion shifts to the lower temperature side and broadens with increasing plasticizer content. These effects are mainly dependent upon the plasticizer species, and of the above plasticizers their plasticizing ability decreases in the order of DOS> DBS> DOP> BBP> TCP. The β-dispersion, whose activation energy was estimated to be 14.3 kcal/mol, first begins to disappear from the higher temperature side with increasing plasticizer content and ultimately vanishes. This effect scarcely depends upon the plasticizer species.Young’s moduli of these samples were measured at −20— +40°C from observing the tensile stress relaxation. The modulus vs. plasticizer content curve shows a maximum. This is an example of “antiplasticization.” The ability of additives to provoke antiplasticization decreases in the reverse order of plasticizing ability, that is, in the order of TCP> BBP> DOP> DBS> DOS.
TL;DR: On the basis of stoichiometric relation of reactions between IAA and peroxidase peroxide compounds a tentative scheme of P-670 formation during the oxidation of IAA was presented and IAA peroxide radical instead of superoxide anion radical was suggested to be an intermediate in the oxidation.
TL;DR: The order of elementary processes bears an obvious relation to the total number of participants, insofar as they behave individually, statistically independent except at the moment of the elementary process; this rule has proved to be a useful key for the analysis of homogeneous reactions that are favored with statistical independence of the participants.
Abstract: The order of elementary processes bears an obvious relation to the total number of participants, insofar as they behave individually, statistically independent except at the moment of the elementary process; the elementary process of first, second, or third order is thus that of one, two, or three participants, respectively, and so on. This rule has proved to be a useful key for the analysis of homogeneous reactions that are favored with statistical independence of the participants. That is, however, often carelessly applied to heterogeneous reactions and encounters difficulties. Elementary processes are termed steps, and the complete set of its participants at the state before or after the step are the initiai or the final system; overall reactions are each considered to be composed of steps. The hydrogen electrode reaction
TL;DR: In the fluorescence spectra of the reaction products of ANM with thiols, the quantum yields increase and the emission maxima shift towards the blue as the solvent polarity decreases, and ANM is thus expected to be a useful fluorescent hydrophobic probe directed to thiol groups in protein.
TL;DR: Findings are interpreted as supporting the view that an abrupt change in the membrane potential and conductance is an electrochemical manifestation of a phase transition of the membrane macromolecules.
TL;DR: In this article, the results showed that the highest concentrations of 210Pb of 19 ± 3dpm/100kg were found in the northern mid-latitudes around 30°N, but longitudinal variation across the North Pacific was not observed.
TL;DR: In this paper, changes in surface composition of copper-nickel alloy plates, with various pre-treatments, were studied by means of Auger electron spectroscopy.
TL;DR: The allocyclic X chromosome of the mouse frequently appears heteropycnotic, showing chromatid apposition, but the feature is not necessarily consistent in conventionally stained metaphases, so the quinacrine mustard fluorescence and acetic saline Giemsa techniques unambiguously delineate the asynchronously replicating, allocy CLX in most metaphase spreads prepared from 6.5–7.5 days old female embryos.
TL;DR: The results suggest that aerosols of PGE2 have a bronchodilating action which could be of use in clinical practice, if untoward responses such as irritation of the pharynx, cough and headache could be avoided.
Abstract: Aerosols of prostaglandin E1 (PGE1) and E2 (PGE2) were evaluated as bronchodilators in 32 subjects (6 normals, 15 with bronchial asthma and 11 with chronic bronchitis). PGE2 caused a significant decrease in pulmonary resistance (mean values 3.2 and 2.6 cm H2O/l/sec before and after inhalation, respectively). There were no significant changes in pulmonary resistance after PGE1. Bronchoconstriction occurred in some subjects whose pulmonary resistance had been within normal limits. Static pulmonary compliance did not show any definite change. The frequency dependence of dynamic compliance was measured in 19 subjects; in 3 the results suggested that bronchoconstriction after PGE1 preferentially affected small airways; in 1 other subject bronchodilatation occurred exclusively in the small airways. Arterial Po2 decreased in 4 out of 5 patients after inhalation of PGE1. This was thought to be due to greater unevenness of the ventilation perfusion ratio, since the dynamic pulmonary compliance became more dependent on respiratory frequency even though pulmonary resistance improved in these subjects. The pulse rate did not change significantly, but mean blood pressure decreased in 8 out of 15 subjects. Cough and irrtation of the pharynx were noted in 42 and 62 per cent of subjects during and after the inhalation of PGE1 and PGe2, respectively. Five and 23 percent of the subjects complained of headache after inhaling PGE1 and PGE2. The results suggest that aerosols of PGE2 have a bronchodilating action which could be of use in clinical practice, if untoward responses such as irritation of the pharynx, cough and headache could be avoided.
TL;DR: It was found that all the preparations except DFR are active in supporting the fertilization of dejellied eggs, and DFD is thermo‐stable, and characterized by a rise in pH accompanying increase in concentration.
Abstract: In an attempt to characterize a factor in anuran egg-jelly that is essential for fertilization, dejellied, non-fertilizable eggs of the toad, Bufo bufo, were inseminated in the following jelly preparations: jelly solubilized by KCN followed by dialysis (Dialyzed jelly: DJ), jelly solubilized by ultraviolet irradiation (UVJ), a diffusible factor released from jelly coat into deionized water (DF), the dialyzable fraction of DF (DFD), and the non-dialyzable fraction of DF (DFR). It was found that all the preparations except DFR are active in supporting the fertilization of dejellied eggs. DFD is thermo-stable, and characterized by a rise in pH accompanying increase in concentration. DF obtained from Rana japonica also capacitated the fertilization of dejellied Bufo eggs.
Chemical analyses indicated that DJ, UVJ, DF and DFR contain various amounts of fucose, hexoses, hexosamines, and proteins. Sialic acid was present in DJ and UVJ, but not in DF. In DFD, only hexoses and proteins were detectable to a measurable degree. A salient feature of the paper chromatographic analyses was the predominance in DFD of an unspecified reducing sugar which was found in common in all the preparations with fertilization-supporting activity. Gel-filtration in combination with bioassay for fertilization led to the isolation of the active substance, which had a molecular weight of less than 500, and was characterized by a basic nature and the presence of a reducing sugar.
The possible importance in fertilization of this small molecular weight jelly component is stressed, together with the suggestion that the component represents some terminal group of the jelly macromolecule in either diffusible or non-diffusible form.
TL;DR: The pH-induced conformational transition of maleic acid-styrene copolymer in aqueous NaCl solutions has been investigated by potentiometric titration, viscosimetry, and dilatometry as mentioned in this paper.
Abstract: The pH-induced conformational transition of maleic acid–styrene copolymer in aqueous NaCl solutions has been investigated by potentiometric titration, viscosimetry, and dilatometry. The dependence of the intrinsic viscosity on the degree of neutralization of the primary carboxyl group indicates that the transition is from a compact to a loosely coiled form. From titration data, the standard free energy change ΔG° per monomole, for the transition from the uncharged compact from to the hypothetical uncharged loosely coiled one is estimated to be about 370–280 cal/monomole for concentrations ranging from 0.0092 to 0.2739N in NaCl. The value of ΔG° decreases slightly with increasing temperature in the temperature range from 15 to 30°C. The volume change associated with the transition was found to be −0.6 ml in 0.01N NaCl and −0.9 ml in 0.09N NaCl per monomole, respectively. From viscosity data, changes of molecular dimensions and the long-range interaction parameter through the transition region have been discussed.
TL;DR: Considering the above findings and other relevant data of some allied species, the differentiation between A. giliacus and A. speciosus might have occurred rather recently, when the former species might have been involved in rapid and divergent chromosomal evolution.
Abstract: Chromosome studies were made on 74 animals of the field mouse, Apodemus giliacus, a new form of the genus Apodemus described by Kobayashi and Hayata (1970). Extreme variations in number and morphology of chromosomes was observed. While the diploid numbers varied from 48 to 61, the number of acrocentric elements was consistently 48, except for one specimen which had 40 such elements. In contrast, the number and constitution of several biarmed elements and microchromosomes were highly variable in the complement, and, hence, responsible for the polymorphism. Karyotype analysis of meiotic chromosomes, on the basis of Giemsaand quinacrine-stained preparations, some familial studies and breeding experiments revealed that variable elements were supernumeraries of a hitherto undescribed type, whereas the 48 acrocentrics seemed to represent regular autosomes and sex elements. Most of the supernumeraries did not show pairing at metaphase I, but some did form bivalents. Usually, the supernumerary biarmed chromosomes were of regular size and fluoresced rather brightly over their entire length, suggesting that they were heterochromatic in nature. Considering the above findings and other relevant data of some allied species, the differentiation between A. giliacus and A. speciosus might have occurred rather recently, when the former species might have been involved in rapid and divergent chromosomal evolution.
TL;DR: The formation of ice crystals, which might be the possible artefact in cryo‐techniques for electron microscopy, was examined during the rewarming process of rapidly frozen erythrocytes.
Abstract: SUMMARY
The formation of ice crystals, which might be the possible artefact in cryo-techniques for electron microscopy, was examined during the rewarming process of rapidly frozen erythrocytes.
Intracellular ice formation, which is usually found in cells suspended in saline by rapid freezing, was inhibited by the addition of 30% glycerol. When such glycerinated cells, having no ice crystals at liquid nitrogen temperature, were rewarmed to higher temperatures above − 80° C, recrystallization of ice occurred. Ice particles became visible within the cells even at − 80°C and grew larger with a temperature rise.
From the results obtained in the morphological and physiological investigations, it also became evident that the recrystallization of ice appeared prior to the increase in haemolysis during the rewarming process.
TL;DR: In this paper, the electronic absorption spectra of four monosubstituted naphthalenes, α-, β-naphthols, and α-, ε-, β naphthylamines have been investigated by means of configuration analysis with particular attention to the dependence of spectra on the position of substitution and on the electron-donating power of the substituent.
TL;DR: From the roots of Cacalia hastata L. subsp.
TL;DR: In this article, the authors investigated the relaxation properties of poly-α-amino acids in the solid state using dielectric, dynamic mechanical, NMR, dilatometric, and X-ray diffraction measurements at temperatures between −196 and 180°C.
Abstract: Relaxation phenomena of poly-α-amino acids in the solid state have been investigated using poly-γ-benzyl-L-glutamate (PBLG), poly-γ-methyl-L-glutamate (PMLG), and copoly (γ-methyl-L-glutamate, γ-benzyl-L-glutamate) (PMBG) by means of dielectric, dynamic mechanical, NMR, dilatometric, and X-ray diffraction measurements at temperatures between −196 and 180°C. Each of the samples exhibits two relaxation regions, one at room temperature (β-relaxation) and the other in the range from −150 to −100°C (γ-relaxation). The γ-relaxation is attributed to motion of the side chains with small amplitude. The β-relaxation is due to large-scale motion of the side chain. It has been found that the β-relaxation is well described by the WLF-equation. The intensity of the X-ray diffraction peak at 2θ = 7° for PBLG increases with increasing temperature, which is similar to results obtained in small-angle X-ray scattering for polymer crystals consisting of two phases, amorphous and crystalline. A break point is observe...
TL;DR: In this paper, the first arrival data from the explosions of 1968 in the sea off Cape Erimo and of 1969 in the Sea off Shakotan Peninsula and at the Teine quarry, have been analyzed to derive the crustal structure in the profile between the coast of Hokkaido and the Shakotsan Peninsula in the southern part of Japan.
Abstract: The first arrival data from the explosions of 1968 in the sea off Cape Erimo and of 1969 in the sea off the Shakotan Peninsula and at the Teine quarry, have been analyzed to derive the crustal structure in the profile between Cape Erimo and the Shakotan Peninsula in the southern part of Hokkaido, Japan. In these explosions, the fixed-array moving shot point technique was applied and the records were obtained from observing stations on land with magnetic-tape-recording systems. Most of the records from the shots off Cape Erimo were not used for the derivation of the crustal structure. The quality of records from the shots off the Shakotan Peninsula was excellent at the stations northwest of the Ishikari-Yufutsu plain, but it was fairly poor at the other stations. The time-term method was applied only to data of the highest possible quality, so that the crustal structure was obtained only in the northwestern half of the profile. Under the explosion site in the Sea of Japan, the crust, consisting of granitic and basaltic layers with nearly the same thickness, is about 17km thick at a point about 50km distant from the shoreline. The crustal thickness increases abruptly toward land and reaches about 30km at a point 40km distant from the shoreline, where the basaltic layer is about twice the thickness of the granitic layer. The velocities obtained in each layer in the crust and in the upper mantle are fairly low, but the gravity anomalies calculated by assuming the densities expected from these velocities agree well with the observed gravity anomalies.