Showing papers by "Lund University published in 1976"
TL;DR: In this article, fracture mechanics is introduced into finite element analysis by means of a model where stresses are assumed to act across a crack as long as it is narrowly opened, which may be regarded as a way of expressing the energy adsorption in the energy balance approach.
5,505 citations
TL;DR: In this article, a review article deals with the X-ray emission induced by heavy, charged particles and the use of this process as an analytical method (PIXE), and a theoretical discussion of the sensitivity is given.
588 citations
01 Jan 1976
TL;DR: In this article, the authors introduce some basic notation and definitions of interpolation spaces and discuss a few general results on the Aronszajn-Gagliardo theorem.
Abstract: In this chapter we introduce some basic notation and definitions. We discuss a few general results on interpolation spaces. The most important one is the Aronszajn-Gagliardo theorem.
540 citations
TL;DR: While the majority of the monoamine-containing neurons in the transplants died within the first month after transplantation, a significant number of neurons survived for at least half a year in the brain.
484 citations
TL;DR: The amine mechanisms demonstrated in human brain vessels appear to be principally the same of those shown in more extensive studies on laboratory animals.
431 citations
TL;DR: In this article, a cranked modified-oscillator model was used to study the nuclear potential energy surface (based on a Strutinsky type of shell correction method) for very high angular momenta (30 ≦ I ≦ 100).
361 citations
TL;DR: A recent study was able to demonstrate the occurrence of VIP, not only in endocrine-like cells, but also in a rich system of gastrointestinal nerves, some of which had a perivascular localization 12.
352 citations
TL;DR: Support is provided for the view that PP is a true pancreatic hormone by the use of specific antisera demonstrated PP immunoreactivity in the pancreas of a number of mammals.
Abstract: A peptide, referred to as pancreatic polypeptide (PP), has recently been isolated from the pancreas of chicken and of several mammals. PP is thought to be a pancreatic hormone. By the use of specific antisera we have demonstrated PP immunoreactivity in the pancreas of a number of mammals. The immunoreactivity was localized to a population of endocrine cells, distinct from the A, B and D cells. In most species the PP cells occurred in islets as well as in exocrine parenchyma; they often predominated in the pancreatic portion adjacent to the duodenum. In opossum and dog, PP cells were found also in the gastric mucosa. In opossum, the PP cells displayed formaldehyde-induced fluorescence typical of dopamine, whereas no formaldehyde-induced fluorescence was detected in the PP cells of mouse, rat and guinea-pig. Also in these latter species, however, PP cells appear to possess amine-handling properties, a feature common to many peptide hormone-producing cells. The ultrastructure of the PP cells was defined by combining immunohistochemistry of semi-thin plastic sections with electron microscopy of adjacent ultrathin sections. PP cells show the ultrastructural features of peptide hormone-secreting cells. The PP cells of cat and dog contain fairly large, rather electron-lucent granules, and are probably identical with the previously described F cells. The PP cells of rat, guinea-pig, chinchilla and man contain small, fairly electron-dense granules. In these latter species no F cells are found. By immunoperoxidase staining of ultrathin sections, the PP immunoreactivity was found to be localized to the cytoplasmic granules. These observations provide support for the view that PP is a true pancreatic hormone.
343 citations
TL;DR: In this article, the authors discuss the determination of the figure of the earth and its gravity field from astrogeodetic and gravimetric data (By gravity we mean the resultant of the attractive force of the masses of the Earth, also called gravitation, and the centrifugal force of earth's rotation).
Abstract: The purpose of this paper is to discuss the determination of the figure of the earth and its gravity field from astrogeodetic and gravimetric data (By gravity we mean the resultant of the attractive force of the masses of the earth, also called gravitation, and the centrifugal force of the earth's rotation) Let us recall that at the surface of the earth: (a) astronomic observations allow one to determine the direction of the gravity vector G; (b) gravimetric measurements give the length I GI of the gravity vector; (c) levelling combined with gravimetric measurements gives the differential of the gravity potential W, and thus yields W apart from an additive constant We assume the measured data G and W corrected for, say, the gravitational interaction with the moon, the sun and the planets, for the precession of the earth, and so on, so that we have the following idealized situation:
309 citations
286 citations
TL;DR: Taipoxin (taipan toxin), purified from the venom of the Australian taipan (Oxyuranus s. scutellatus) by gel filtration on Sephadex G-75 followed by column zone electrophoresis, is the most lethal neurotoxin yet isolated from any snake venom.
Abstract: Taipoxin (taipan toxin), purified from the venom of the Australian taipan (Oxyuranus s. scutellatus) by gel filtration on Sephadex G-75 followed by column zone electrophoresis, is the most lethal neurotoxin yet isolated from any snake venom. The LD50 is 2 mug/kg in the mouse. The main physiological effect is a gradual reduction to complete stop of evoked and spontaneous release of acetylcholine from motor nerve terminals. Intoxicated animals die of asphyxia caused by neuromuscular blockage of the respiratory muscles. Taipoxin is a moderately acidic sialo-glycoprotein (pI 5) with a molecular weight of 45 600 as calculated from composition data or 46 800 as determined by meniscus depletion sedimentation equilibrium. Taipoxin is a 1:1:1 ternary complex of subunits designated alpha, beta and gamma which dissociate completely at low pH and high ionic strength or in 6 M guanidine hydrochloride. The dissociation by guanidine at neutral pH is reversible, while the acid-induced dissociation is not . The alpha and beta components consist of 120 amino acid residues cross-linked by seven disulfide bridges, whereas the gamma component has 135 residues and eight disulfides. The very basic (pI Greater than 10) alpha component contains 13 residues of arginine and is the only subunit displaying lethal neurotoxicity (mouse LD50 approximately 300 mug/kg). The neutral beta fraction was separated by ion-exchange chromatography into two iso-component, beta 1 and beta2, which differ slightly in amino acid composition. The very acidic gamma component contains all of the carbohydrate, which includes 4-5 residues of sialic aid. The three subunits are homologous in sequence although the gamma component is eight residues longer on the N-terminus and must also contain extra amino acids elsewhere.
TL;DR: Data are presented showing that SpA is a highly efficient mitogen for human peripheral B lymphocytes, with no detectable activity for T lymphocyte, in order to achieve optimal stimulating conditions SpA should be presented to the lymphocytes on an insoluble matrix.
Abstract: Protein A from Staphylococcus aureus (SpA) is known to bind to the Fc region of most mammalian IgG classes. In the present article data are presented showing that SpA is a highly efficient mitogen for human peripheral B lymphocytes, with no detectable activity for T lymphocytes. In order to achieve optimal stimulating conditions SpA should be presented to the lymphocytes on an insoluble matrix, such as the SpA-positive bacteria themselves or SpA covalently attached to Sephadex or Sepharose beads. Using such conditions SpA is equivalent with regard to stimulatory capacity for B lymphocytes as phytohemagglutinin is for the human T lymphocytes. Specificity controls proved beyond doubt that SpA and not any other contaminating product is the B cell mitogen. It is concluded that SpA as an inducer of human B lymphocyte division might serve as a highly useful assay in the clinical assessment of B lymphocyte function. It should also be a suitable tool in the fine analysis of B lymphocyte activation via the specific interactions with surface IgG molecules.
TL;DR: Transplants of adrenergic, dopaminergic or indolaminergic neurones were transplanted to a cavity in the retrosplenial cortex to give them the opportunity to grow along the lesioned temporoammonic perforant path into the partly denervated hippocampal formation, demonstrating a remarkable ability of the regenerating axons to establish reproducible and characteristic terminal patterns in large areas of the hippocampus.
Abstract: CENTRAL and peripheral monoaminergic neurones have been found to survive transplantation to certain sites in the adult rat brain1. The neurones grow extensively in their new location and the newly formed axons extend through the surrounding scar tissue into the host brain. We now report experiments in which transplants of adrenergic, dopaminergic or indolaminergic neurones were transplanted to a cavity in the retrosplenial cortex to give them the opportunity to grow along the lesioned temporoammonic perforant path into the partly denervated hippocampal formation. The results demonstrate a remarkable ability of the regenerating axons to establish reproducible and characteristic terminal patterns in large areas of the hippocampus.
01 Jan 1976
TL;DR: Critical evaluation of this knowledge reveals that most progress has been achieved during the past fifteen years after electron microscopic application, which requires better resolution than that obtained with the light microscope.
Abstract: Considerable knowledge of microsporidian structure has been accumulated during 150 years of research. Critical evaluation of this knowledge reveals, however, that most progress has been achieved during the past fifteen years after electron microscopic application. Although some light microscope observations have contributed amazingly accurate data on microsporidian structure, the extreme smallness of microsporidia (the spores of which are probably the smallest eukaryotic cells) as well as the compactness and complexity of their structural organization requires better resolution than that obtained with the light microscope.
TL;DR: The EEG frequency also correlates with the blood flow of the gray matter of the brain when tissue anoxia has not uncoupled the normal function--flow relationship prevailing in the brain.
TL;DR: The incidence of osteochondritis dissecans in the condyles of the femur was studied in a defined population and was found to be twice as common in men as in women; the maximum incidence in both sexes being between the ages of 10 and 20.
Abstract: The incidence of osteochondritis dissecans in the condyles of the femur was studied in a defined population and was found to be twice as common in men as in women; the maximum incidence in both sexes being between the ages of 10 and 20. The site of the lesion in the condyles did not differ between age groups. The indicence of diagnosied cases has increased somewhat in recent years but only in men. The incidence in the population is less than has been suggested in the past.
TL;DR: Further purification of a urokinase preparation by chromatography on benzamidine-Sepharose is described, and a monospecific antiserum against uro Kinase was raised.
TL;DR: The frequency of women using an intrauterine contraceptive device among 515 patients presenting with acute, laparoscopically verified salpingitis, has been compared with the corresponding frequency in 741 sexually active women who were matched to the patients by date of birth, domicile, and socioeconomic status.
TL;DR: System identification techniques are applied to determine ship steering dynamics and parameters of a linear continuous time model are determined using discrete time measurements using the maximum likelihood method.
TL;DR: Two remarkable findings are reported: the existence of two types of fertile female with different somatic sex chromosome constitutions—the orthodox female complement, XX, and the male complement, XY, and evidence for selective non-disjunction in XY females, leading to the formation of X-type egg cells only.
Abstract: THE wood lemming (Myopus schisticolor Lilljeborg), a small rodent inhabiting mossy forests of northern coniferous areas of Eurasia, is unique with respect to sex ratio, showing a definite prevalence of females, and with respect to the occurrence of two types of female, one producing daughters only, the other producing progeny of both sexes1,2. We thought that these phenomena might be associated with chromosome constitution, and as the chromosomes of this species were poorly known, we have made a detailed study of its karyotype. Some additional observations, pertinent both to the occurrence of chromosome variation and to reproduction, will be reported elsewhere. We report here two remarkable findings: (1) the existence of two types of fertile female with different somatic sex chromosome constitutions—the orthodox female complement, XX, and the male complement, XY, and (2) evidence for selective non-disjunction in XY females, leading to the formation of X-type egg cells only.
TL;DR: The concept of a key position for alpha2-macroglobulin in the protective mechanisms against endogenous proteases is supported, which suggested a breakdown of complexes by cells in the reticuloendothelial system.
Abstract: 1. Complexes of human trypsin and human granulocyte elastase with alpha1-anti-trypsin and alpha2-macroglobulin were isolated and injected intravenously into human volunteers. 2. The elimination of alpha2-macroglobulin complexes with trypsin and elastase followed single-exponential functions with half-lives of 9 and 12 min respectively. The complexes showed no tendency to dissociate. 3. Complexes of alpha1-anti-trypsin with trypsin persisted in the circulation much longer, with a half-life of 3-5 h; complexes of alpha1-anti-trypsin with elastase had an intermediate half-life of 1 h. 4. Dissociation was observed of alpha1-anti-trypsin complexes with transfer of trypsin and elastase to alpha2-macroglobulin. 5. Dialysable radioactivity appeared in the urine soon after the injection of alpha2-macroglobulin complexes, which suggested a breakdown of complexes by cells in the reticuloendothelial system. Radioactivity over the liver achieved maximum values within 30-40 min after the injection of alpha2-macroglobulin complexes but not until 50-70 min after the injection of alpha1-anti-trypsin comlexes. 6. These results support the concept of a key position for alpha2-macroglobulin in the protective mechanisms against endogenous proteases.
TL;DR: In this paper, Fan's fixed-point theorem and the existence of an equilibrium in a generalized game are extended to a larger class of orderings, which allows one to generalize slightly several existence theorems and seems to be useful for the applications.
TL;DR: Fingerprint and amino acid analysis of a corresponding CNBr-fragment of 63 amino acids from M and Z protein give clear evidence for an amino acid substitution, glutamic acid to lysine.
TL;DR: In this article, the enthalpies of solution in water of D 6 -benzene, toluene, ethylbenzenes, propylbenenzene, and cyclohexane have been determined in the temperature range 288 to 308 K by a flow-microcalorimetric technique.
TL;DR: The apparent identity of this plasminogen-activating enzyme, released by ovarian carcinoma in tissue culture, and the activator produced by foetal kidney and present in normal urine—that is, urokinase are reported here.
Abstract: THERE is evidence that fibrinolytic enzymes are involved in the growth of tumours. It has long been known that malignant tumours in culture lyse clotted plasma substrates1–3. Davidson et al.4 found a giant-cell carcinoma of the lung to be rich in plasminogen activator and to produce it in tissue culture. Rifkin et al.5 reported an abundant release of fibrinolytic enzymes by mammalian fibroblasts transformed by DNA or RNA viruses, by chemically or virally induced mammary carcinomas and by human malignant tumours in culture. Normal fibroblasts and cultures of other normal tissues released little or no fibrinolytic enzymes. Christman and Acs6 found neoplastic cells, whether transformed by oncogenic viruses or by chemical agents, to release a plasminogen activator not released by normal cells. This activator was characterised as a serine protease with a molecular weight of approximately 50,000. The presence of fibrinolytic activity has been demonstrated in human ovarian tumours7 as well as in ascitic fluid associated with such tumours8. We have studied a stable plasminogen-activating enzyme, released by ovarian carcinoma in tissue culture, and we report here the apparent identity of this plasminogen activator (TA) and the activator produced by foetal kidney and present in normal urine—that is, urokinase.
Journal Article•
TL;DR: The hypothesis that factor VIII may exert its effect on primary hemostasis locally in the vessel wall, VIIIAGN and its relationship with the bleeding time were studied by direct immunofluorescence in gum-biopsy specimens obtained in vWd patients before cryoprecipitate infusion.
TL;DR: The Center-Edge angle (CE angle) of Wiberg was measured in normal hips in patients between 8 and 75 years of age and increased with growth up to adult age, and then only slowly.
Abstract: The Center-Edge angle (CE angle) of Wiberg was measured in normal hips in patients between 8 and 75 years of age. Males and females were recorded separately. Means and standard deviations are presented here. The angle increased with growth up to adult age, and then only slowly. In children only values below 15 degrees can be classified as abnormal.
TL;DR: 29 boys (4–18 years old) with severe haemophilia A were given prophylactic infusions of AHF concentrate for 2 to 13 years in an attempt to change the haemophile from a severe to a moderate form and thereby prevent arthropathy and severe bleeding episodes.
Abstract: 29 boys (4-18 years old) with severe haemophilia A were given prophylactic infusions of AHF concentrate (human fraction I-0) for 2 to 13 years in an attempt to change the haemophilia from a severe to a moderate form and thereby prevent arthropathy and severe bleeding episodes. The sizes of the doses and the intervals at which the doses were given were titrated by AHF survival studies. As a rule, the patients received AHF in amounts sufficient to raise the AHF level to 30-45% at 5-12 day intervals. In about 50% of the infusions the AHF content was not below 1% before the next infusion. During such prophylaxis all patients except one have been in a good general condition. They have had bleeding episodes, which have, however, been much less severe and less frequent. The children have been able to live an almost normal life. The number and duration of stays in hospital have been markedly reduced. 17 of the patients had only minor or no joint defects before the start of the treatment. In this group the joint function was identical with that found in moderate haemophilia in the same age groups. Two patients developed anticoagulants. No other side effects were seen. The prophylactic regimen in Sweden thus reduced severe haemophilia to moderate.