Showing papers by "University of Copenhagen published in 1973"
TL;DR: A new method for determination of uronic acids with meta-hydroxydiphenyl is introduced, which is simpler, quicker, more sensitive, and more specific than other methods, and it needs lesser amounts of fluid.
6,302 citations
TL;DR: In this paper, it was shown that a Higgs type of Lagrangian allows for vortex-line solutions, in analogy with the vortex lines in a type II superconductor.
2,172 citations
TL;DR: The results show that the principle binding of insulin by fat cells occurs to a group of receptors with a Kd of 3 · 10−9 M and that the degradation of insulin and the receptor binding are processes independent of each other, suggesting that the stimulatory effect of insulin on lipogenesis from glucose in fat cells is mediated by these receptors.
327 citations
TL;DR: The increased transcapillary escape rate and the outflux of albumin probably reflected an increase in arteriolar and capillary permeability to albumin, due to the high intra-arterial pressure.
Abstract: The transcapillary escape rate of albumin, the fraction of intravascular mass of albumin that passes to the extravascular space per unit time, was determined from the disappearance of intravenously injected 131I-labeled human serum albumin during the first 60 minutes after the injection in 10 normotensive and 18 hypertensive male subjects. The investigation was preceded by at least 12 hours of fasting and 30 minutes of rest in the supine position. The transcapillary escape rate of albumin was significantly increased in the hypertensive group: it averaged 7.6±1.2 (SD) %/hour compared with 5.6±1.1%/hour in the normotensive group (P<0.001). Similar results were obtained for the outflux of albumin, the mass of intravascular albumin that passes to the extravascular space per unit time, when identical intravascular albumin masses were compared (P<0.001). A highly significant correlation between the transcapillary escape rate of albumin and blood pressure was found in the hypertensive group (P<0.001). Therefore,...
249 citations
TL;DR: Several theoretically interesting forms of the nucleon EM form factor have been considered and found to provide quantitative descriptions of available data with as few as three adjustable parameters as discussed by the authors, but none of them can be used to provide a quantitative description of the available data.
240 citations
TL;DR: A principle for altering rapidly and drastically the intracellular ionic strength by varying the concentrations of monovalent cations and anions is given.
Abstract: THE human red cell membrane is as impermeable to K and Na ions (P=10−11 cm s−1) as an unmodified lipid bilayer1 and has a low permeability (P=10−8 cm s−1) to Cl moving as a free ion. A permeability coefficient of 10−11 cm s−1 is as low as that estimated for unmodified lipid bilayer membranes, which are essentially impermeable to alkali metal cations and anions. Because of this low permeability, studies of active and passive ion transport that require control of both ion concentration and ionic strength have been virtually restricted to work on red cell ghosts prepared by haemolysis and on perfused giant squid axons3. Here we give a principle for altering rapidly and drastically the intracellular ionic strength by varying the concentrations of monovalent cations and anions.
237 citations
TL;DR: In this article, a noncommutative Radon-Nikodym theorem was used to show that a von Neumann algebra is semi-finite if and only if it consists of inner automorphisms.
Abstract: Let ϕ be a faithful normal semi-finite weight on a von Neumann algebraM. For each normal semi-finite weight ϕ onM, invariant under the modular automorphism group Σ of ϕ, there is a unique self-adjoint positive operatorh, affiliated with the sub-algebra of fixed-points for Σ, such that ϕ=ϕ(h·). Conversely, each suchh determines a Σ-invariant normal semi-finite weight. An easy application of this non-commutative Radon-Nikodym theorem yields the result thatM is semi-finite if and only if Σ consists of inner automorphisms.
212 citations
TL;DR: Human serum proteins were analyzed by crossed immuno-affinoelectrophoresis and affinity chromatography on concanavalin A bound to Sepharose and concordant results were obtained.
209 citations
TL;DR: In this paper, it was shown that a multiplier of a quotient of A is the image of an element from M ( A ), if A is separable and if M(A) A is non-simple.
204 citations
199 citations
TL;DR: Experimental data on transfer reactions in the /sup 40/Ar + /sup 232/Th system are interpreted in terms of nuclear orbiting combined with dissipation of energy due to the friction forces as discussed by the authors.
TL;DR: It is concluded that cortisol is not the prime determinant of blood pressure during and after surgery in glucocorticoid-treated patients, that stress-induced acute adrenocortical insufficiency must be infrequent in these patients, and that an absence of an adrenocortsical response to minor surgery cannot be taken as the sole indication of pathological adrenOCortical function.
Abstract: Adrcnocortical function, as expressed by repeated plasma corticosteroid measurements and the clinical course, were studied in 104 glucocorticoid-treated patients undergoing surgery without supplementary glucocorticoid administration. Eight patients developed otherwise unaccountable hypotension during surgery but only 1 patient showed concomitant low plasma corticosteroid values. Eighteen patients had minimal adrenocortical function without accompanying signs of adrenocortical insufficiency. Postoperatively, 4 patients developed hypotension, which could not be correlated to cortisol deficiency. It is concluded that cortisol is not the prime determinant of blood pressure during and after surgery in glucocorticoid-treated patients, that stress-induced acute adrenocortical insufficiency must be infrequent in these patients, and that an absence of an adrenocortical response to minor surgery cannot be taken as the sole indication of pathological adrenocortical function.
TL;DR: The time-course of the cell-mediated immunity has been established in acutely infected mice and in virus carriers adoptively immunized with syngeneic sensitized lymphocytes, and experiments seem to indicate that the underlying mechanism in the cytotoxic reaction is a direct cell-to-cell interaction.
Abstract: A large amount of experimental evidence has already been presented indicating the great importance of the cell-mediated immunity in the pathogenesis of the LCM virus infection in mice. In this laboratory a method which makes it possible to measure this cellular immunity quantitatively in vitro has been developed. The method is based on the determination of the radioisotope released after the interaction between specifically sensitized lymphocytes and syngeneic 1Cr-labeled LCM virus-infected target cells. By using this technique the time-course of the cell-mediated immunity has been established in acutely infected mice and in virus carriers adoptively immunized with syngeneic sensitized lymphocytes. Lymphocytes from acutely infected mice showed a strong lysing effect on the target cells, with a sharp maximum at about the 9th day after infection. The cell-mediated immunity in adoptively immunized virus carrier mice showed the same time-course, but in these animals the lytic effect of the lymphoid cells was considerably less pronounced. Lymphocytes from untreated virus carriers did not, however, have any effect on the target cells, and in these animals it was not possible to demonstrate any evidence of enhancing antibodies, In experiments employing serial dilutions of sensitized lymphocytes in normal cells a direct linear relationship between the number of sensitized lymphocytes and target cell destruction was found. These experiments seem to indicate that the underlying mechanism in the cytotoxic reaction is a direct cell-to-cell interaction.
TL;DR: In this article, the correlation between single-particle degrees of freedom and the vibrational field and the Pauli principle for three particles or holes in the valence shell is investigated.
TL;DR: The presence of K10, which increases crossing-over frequencies and promotes intimate pairing at the light microscopic level, was thus found to permit formation of complete synaptonemal complexes in the inverted region.
Abstract: Aldehyde fixation followed by staining with phosphotungstic acid produces differential contrast between the synaptonemal complex and the chromatin of maize pachytene bivalents. Centromeres, heterochromatic knobs and large chromomeres are easily recognised. With this and other staining techniques the nucleolus organizer region can be differentiated into two components. — Microsporocyte nuclei at pachytene were serially sectioned and all ten bivalents reconstructed in five nuclei. An idiogram was derived from the mean chromosome (= synaptonemal complex) lengths, the arm ratios, positions of knobs and the nucleolus organizer region. The idiogram agrees well with that published from light microscopic analyses. However, bivalent lengths are only two thirds of those observed by light microscopy of squash preparations. Many telomeres of the bivalents are connected via chromatin to the nuclear envelope, but a varying number of free bivalent ends are observed in all five reconstructed nuclei. — Bivalents heterozygous for inversion 3b were reconstructed. In the presence of abnormal chromosome 10 (K10) the lateral components of the synaptonemal complex of chromosome 3 formed a typical inversion loop, while in one of the nuclei having no K10 the two lateral components of the long arms of chromosome 3 remained unpaired in the region of inversion heterozygosity. The presence of K10, which increases crossing-over frequencies and promotes intimate pairing at the light microscopic level, was thus found to permit formation of complete synaptonemal complexes in the inverted region. The extra terminal portion of the K10 chromosome folded back on itself and formed a morphologically normal synaptonemal complex in this — possibly non-homologously paired — region. The chromatin of centromeres and knobs from different bivalents were sometimes found to fuse, but the synaptonemal complexes transversing the fused centromeres or knobs retained their individuality.
TL;DR: In this paper, it was shown that concurrently with the increasing availability of pornography, there was a significant decrease in the number of sex offenses registered by the police in Copenhagen, and that at least in one type of crime (child molestation) the decrease represents a real reduction in the amount of offenses committed.
Abstract: The Danish liberalization of legal prosecution and of laws concerning pornography and the ensuing high availability of such materials present a unique opportunity of testing hypotheses concerning the relationship between pornography and sex offenses. It is shown that concurrently with the increasing availability of pornography there was a significant decrease in the number of sex offenses registered by the police in Copenhagen. On the basis of various investigations, including a survey of public attitudes and studies of the police, it was established that at least in one type of offense (child molestation) the decrease represents a real reduction in the number of offenses committed. Various factors suggest that the availability of pornography was the direct cause of this decrease.
TL;DR: In this article, the mean multiplicity, as a function of s, and the KNO scaling function are universal, and asymptotically the ratio σelastic/σtotal is expected to be the same for all processes.
TL;DR: In this article, a range and damage distribution for light ions slowing down in heavy targets in the energy region where electronic stopping is dominating and approximately proportional to velocity was calculated for light ion bombarding a thin film.
Abstract: Range and damage distributions have been calculated for light ions slowing down in heavy targets in the energy region where electronic stopping is dominating and approximately proportional to velocity. Following Schi⊘tt's approach, well-known integral equations for spatial moments were approximated by differential equations, and the latter solved by numerical integration. Moments over the two distributions up to third order have been obtained, and the distributions were constructed by use of the Edgeworth expansion. From the profiles, backscattering coefficients and relative sputtering yields were determined. Comparison is made with previous theoretical results, computer simulation and experimental results. An improved calculation of the sputtering yield of light ions bombarding a thin film is also presented.
TL;DR: In this paper, reversible behavior for both electron transfers for oxidation of aromatic compounds to cation radicals and dications was observed in several common electrolytic solvents, including trifluoroacetic acid and corresponding acid anhydride.
01 Jan 1973
TL;DR: The description of many-body systems at low energy in terms of "elementary modes of excitation" (see, e.g., Noz 65) is very useful in the case of nuclei as discussed by the authors.
Abstract: The description of many-body systems at low energy in terms of “elementary modes of excitation” (see, e.g., Noz 65) is very useful in the case of nuclei (see BM 69). “Elementary modes of excitation” as used here comprise collective (rotations and vibrations) as well as quasiparticle excitations. In order to study the various modes, experiments are required which selectively excite one such degree of freedom while all the others remain inactive spectators.
TL;DR: Gass has suggested that mantle plumes drive the movement of lithospheric plates may be demonstrated in the Red Sea area as mentioned in this paper, where the Afar plume is located at the triple junction formed by the Gulf of Aden, Red Sea and Ethiopian rifts.
Abstract: ICELAND, a site of anomalous heat flow, volcanism and topography, may represent the surface expression of a rising mantle plume1–10. Gass has suggested that evidence that mantle plumes drive the movement of lithospheric plates may be demonstrated in the Red Sea area11–13. Geochemical effects of the Afar plume, located at the triple junction formed by the Gulf of Aden, Red Sea and Ethiopian rifts, are also striking14.
TL;DR: Transcapillary escape rate of albumin was found significantly increased in the long-term diabetics with microangiopathy, compared to the short-term diabetic and the non-diabetic groups, and it is assumed that the increased transcapillary Escape rate and the outflux ofalbumin reflect an increased microvascular permeability to albumin.
Abstract: Transcapillary escape rate of albumin (fraction of intravascular mass of albumin that passes to the extravascular space per unit time) was determined from the disappearance of intravenously injected 131I-human serum albumin during the first 60 min after injection in 14 non-diabetics, 12 short-term diabetics (mean duration of diabetes 2.6 years), and 21 long-term diabetics with microangiopathy (mean duration of diabetes 20 years). Transcapillary escape rate of albumin was found significantly increased in the long-term diabetics with microangiopathy, average 7.8 (S.D. 0.9) per cent/hour, compared to the short-term diabetic and the non-diabetic groups, average 5.5 (S.D. 1.0) and 5.9 (S.D. 1.0) per cent/hour, respectively. Similar results were obtained for the outflux of albumin (mass of intravascular albumin that passes to the extravascular space per unit time). It is assumed that the increased transcapillary escape rate and the outflux of albumin reflect an increased microvascular permeability to albumin, d...
TL;DR: In this paper, a dynamic model based on the force equilibrium concept was proposed to estimate the critical angular momentum in the entrance channel for reactions between complex nuclei, and the nucleus-nucleus force was derived from simple surface energy considerations.
TL;DR: The spermatophore is necessary to ensure the functioning of the female system at copulation and related problems concerning the genital organs of Helix pomatia were studied by means of morphological and experimental methods.
Abstract: In the Helicidae and in some other Stylommatophora the sperm are transferred in a spermatophore, even though there appears to be no need for protection of the sperm during the transfer. The function of the spermatophore and related problems concerning the genital organs of Helix pomatia were studied by means of morphological and experimental methods.
The spermatophore is necessary to ensure the functioning of the female system at copulation. Its structure allows some of the spermatozoa it contains to escape through its tail canal, pass from the stalk of the bursa and reach the spermatheca by way of the oviduct; but most of the sperm pass into the bursa copulatrix and are destroyed, as is also the fate of the spermatophore. Only foreign sperm are stored in the spermatheca.
Spermiogenesis was found to take place throughout the whole summer. At intervals some sperm are released from the hermaphrodite duct and are conducted via the spermoviduct and oviduct to the bursa, where they are digested. The two grooves of the spermoviduct are functionally separated only for a few minutes at actual copulation, when sperm are conducted to the copulatory organs, where the spermatophore is being formed.
TL;DR: In this paper, a local field theory for dual strings is developed, which contains the dual string recently discussed by Goddard, Goldstone, Rebbi, and Thorn, and the Lagrangian is given by (−12α')√F2.
TL;DR: Children with mental ages of 3 and 4 years needed 20% more time to accept treatment than did children with higher mental ages, and the time-span for acceptance was 20% greater for 3-year-old children than for older children when IQ values were ≥68.
Abstract: — In order to investigate the influence of mental development on children's acceptance of dental treatment, the mental ages of 108 individuals with a chronologic age of 3–9 years were determined by a psychologist using Binet's, Cattell's, and Leiter's psychometric tests. The degree of acceptance in accordance with given definitions and the time spent for acceptance were recorded. Mental age as well as chronologic age influence children's acceptance of dental treatment, but mental age has the greater influence. A mental age of 29 months separated in this investigation distinctly between children with and without acceptance. Children with mental ages of 3 and 4 years needed 20% more time to accept treatment than did children with higher mental ages. The time-span for acceptance was 20% greater for 3-year-old children than for older children when IQ values were ≥68. For the age classes 5–9 years the time span was 25–30% greater for children with IQ values <68 than for children with IQ values ≥68.
TL;DR: The present article describes how such a standardization was approached in this laboratory within the field of Candida albicans immunochemistry, and found that strain B 311 contained no specific antigens in comparison to eight other strains of C.Albicans.
Abstract: Quantitative immunoelectrophoresis allows a polyvalent approach to immuno-chemical problems, i.e., identification, quantitation, and thereby standardization of antigens and antibodies in complex mixtures, for example as in crude extracts of microorganisms and their corresponding antisera. This approach is a short cut to conventional standardization of single purified substances, since the polyvalent approach gives a precise quantitative impression as described in this investigation and therefore enables the immunochemist to precisely select the right substance(s) to be purified for further standardization and characterization. To secure the precision of the results, in complex systems it is a sine qua non to select a complex antibody standard, a complex antigen standard, and to describe the complex standard precipitate pattern which again allows a quantitative study of the reproducibility of methods and procedures. The present article describes how such a standardization was approached in this laboratory within the field of Candida albicans immunochemistry. By means of crossed immunoelectrophoresis, 78 water-soluble antigens were demonstrated and enumerated in an antigen standard prepared from one strain of C. albicans A (B 311 Hasenclever). The antibody standard consisted of purified and concentrated rabbit antibodies. The migration velocity of each antigen was indicated in relation to purified human albumin. Not all precipitates could be seen in one immunoplate; therefore a standardized procedure was worked out showing reproducibly 54 precipitates. The reproducibility of quantitation by the crossed-immunoelectrophoresis procedure was determined for each of 30 antigens by repeated measurements; the relative standard deviations ranged from 2.4 to 15.4% and were below 10% for 24 antigens. A simple standardized antigen production procedure was described in great detail, and by quantitative determinations on 30 antigens the procedure was found to be satisfactorily reproducible. By means of crossed-line immunoelectrophoresis in the modification called absorption of antibodies in situ, it was found that strain B 311 contained no specific antigens in comparison to eight other strains of C. albicans. Thirty antigens were quantitated in antigen preparations made by the standardized procedure from the eight strains, and each antigen concentration was expressed as a percentage of the antigen standard. For each antigen a significant inter-strain variation was observed. Of 30 antigens, fifteen were satisfactorily stable after storage at −20 C for 1½ years. The laboratory methods and procedures described in this article thus work with high precision and allow a rapid collection of quantitative data concerning many individual antigens and their corresponding antibodies without purification of antigens. A new complex antigen standard can be made with satisfactory precision from strain B 311. The production of a similar complex antibody standard is a major problem; therefore the main problem in the intra-laboratory standardization seems to be the change from one complex standard to another. In inter-laboratory standardization on the complex level, there seems to be a minimum demand that the first laboratory distributes the antibody standard and that other laboratories use the methods and procedures of the first laboratory.
TL;DR: The results are discussed with regard to the oxidation of acetaldehyde and to the transfer of reducing equivalents from cytosol to mitochondria during ethanol metabolism.
Abstract: 1
The primary product of the well-known oxidation of acetaldehyde by rat liver mitochondria is acetate. About 50% of the acetate formed from acetaldehyde is converted to ketone bodies under the experimental conditions used.
2
The oxidation of acetaldehyde by rat liver mitochondria is catalyzed mainly by an aldehyde: NAD oxidoreductase present in the matrix compartment of the mitochondria. About 20% of the total mitochondrial acetaldehyde dehydrogenase activity may be confined to the outer membrane or the intermembrane space.
3
The enzyme has a broad substrate specificity, pH-optimum at about pH 9.0 and is inhibited by tetraethylthiuram disulfide, chloral hydrate and arsenite. The enzyme is steroid-insensitive.
Two Km-values for acetaldehyde, below 0.1 μM and 1.0 mM, and two Km-values for NADM+, 2 μM and 50 μM, were obtained with a partially purified 100000 ×g supernatant. The presence of two aldehyde dehydrogenases in rat liver mitochondria could not be shown.
4
Oxidation of acetaldehyde by rat liver mitochondria causes an inhibition of the production of 14Co2, from [14C]palmitate. The inhibition can be accounted for by dilution of the acetyl-coenzyme A pool of the mitochondria.
The 3-hydroxybutyrate/acetoacetate ratio during acetaldehyde oxidation is kept at the same level as during oxidation of oleate plus coenzyme A.
5
The mitochondrial acetaldehyde dehydrogenase activity is 80% of the total acetaldehyde dehydrogenase activity of rat liver. The results are discussed with regard to the oxidation of acetaldehyde and to the transfer of reducing equivalents from cytosol to mitochondria during ethanol metabolism.
TL;DR: The variation in the pool sizes during transformation was paralleled by the variation of the rate of incorporation of labeled deoxy-thymidine into cellular DNA, which increased in the pools of 20 and 170 fold, respectively.
TL;DR: The tubules with a diameter of 45 nm characteristic for meiotic prophase nuclei gave a chromatin type reaction, when treated with EDTA according to Bernhard's technique, thus suggesting that these tubules contain DNA.
Abstract: Meiosis in male Drosophila melanogaster was studied with the electron microscope. The number and the distribution of ring channels between individual members of a cluster of primary spermatocytes was determined from serial sections. The tubules with a diameter of 45 nm characteristic for meiotic prophase nuclei gave a chromatin type reaction, when treated with EDTA according to Bernhard's technique, thus suggesting that these tubules contain DNA. A material resembling central regions of synaptinemal complexes was observed in the nucleolus of primary spermatocytes during the downward movement in the testis. It is suggested that they represent unused precursors to central components of synaptinemal complexes, which are absent at pachytene of Drosophila males. Up to six tail fibers (kinetosomes + axonemes) were observed in every primary spermatocyte prior to meiosis.