WILBERT

Wildauer Bücher+E-Medien Recherche-Tool

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Annals of biomedical engineering 13 (1985), S. 451-467 
    ISSN: 1573-9686
    Keywords: Percutaneous implants ; Dogs ; Rabbits ; Goats ; Extrusion ; Marsupialization ; Permigration ; Infection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Percutaneous devices permanently protrude through a surgically created defect in the skin. Usually they provide a connection for intracorporeal implants or organs with external devices. The skin penetration area presents unique medical problems. The interfacing tissue usually does not heal and seal to the implant but remains a focus of constant acute or chronic inflammation and eventually breaks down because of infection. This pathophysiological phenomenon has been studied previously with qualitative light microscopical methods. A large number of empirical studies have attempted to improve the implant-epidermal seal with various implant materials and designs. To allow systematic studies of the effect of biomaterials on implantepidermal interface phenomena, quantitative histological parameters were evaluated. Test implants were made from Dacron velour and placed in dogs, goats, and rabbits for various preselected periods to determine time- and species-related histopathological variations. Results showed that the degree of connective tissue “maturity” within the pores of the implant appears to be related to the concentration of giant cells and polymorphonuclear granulocytes (histocompatibility). The process of epidermal proliferation around porous percutaneous implants appears to follow certain fixed patterns under different conditions that are accompanied by expelling forces, resulting in an outward movement of the implant until it is completely extruded. The presence of microhematomas throughout the implantation period indicates that mechanical forces disrupt interfacial tissue bridges. The basic histological processes are qualitatively the same in the three animal species studied. However, there are quantitative differences with regard to epidermal migration rate and connective tissue maturation within the implant pores, which may explain the different failure modes and times observed among species. The study indicated that percutaneous healing may be directly related to histocompatibility of the implant material, mechanical interfacial forces, and epidermal proliferative patterns. The first two may eventually be controlled by selection of optimal implant materials and device configurations. The control of epidermal migration, however, will be the key to prolonging percutaneous implant life.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Solid State Communications 25 (1978), S. 57-59 
    ISSN: 0038-1098
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    ISSN: 0304-8853
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    BioMed Central
    Publication Date: 2015-04-24
    Description: Background: Excitotoxicity (the toxic overstimulation of neurons by the excitatory transmitter Glutamate) is a central process in widespread neurodegenerative conditions such as brain ischemia and chronic neurological diseases. Many mechanisms have been suggested to mediate excitotoxicity, but their significance across diverse excitotoxic scenarios remains unclear. Death Associated Protein Kinase (DAPK), a critical molecular switch that controls a range of key signaling and cell death pathways, has been suggested to have an important role in excitotoxicity. However, the molecular mechanism by which DAPK exerts its effect is controversial. A few distinct mechanisms have been suggested by single (sometimes contradicting) studies, and a larger array of potential mechanisms is implicated by the extensive interactome of DAPK. Results: Here we analyze a well-characterized model of excitotoxicity in the nematode C. elegans to show that DAPK is an important mediator of excitotoxic neurodegeneration across a large evolutionary distance. We further show that some proposed mechanisms of DAPK’s action (modulation of synaptic strength, involvement of the DANGER-related protein MAB-21, and autophagy) do not have a major role in nematode excitotoxicity. In contrast, Pin1/PINN-1 (a DAPK interaction-partner and a peptidyl-prolyl isomerase involved in chronic neurodegenerative conditions) suppresses neurodegeneration in our excitotoxicity model. Conclusions: Our studies highlight the prominence of DAPK and Pin1/PINN-1 as conserved mediators of cell death processes in diverse scenarios of neurodegeneration.
    Electronic ISSN: 1471-2202
    Topics: Medicine
    Published by BioMed Central
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    American Institute of Physics (AIP)
    Publication Date: 2016-10-19
    Description: Double perovskite Bi 2 FeMnO 6 is a potential candidate for the single-phase multiferroic system. In this work, we study the magnetic, electronic, and optical properties in BFMO by performing the density functional theory calculations and experimental measurements of magnetic moment. We also demonstrate the strain dependence of magnetization. More importantly, our calculations of electronic and optical properties reveal that the onsite local correlation on Mn and Fe sites is critical to the gap opening in BFMO, which is a prerequisite condition for the ferroelectric ordering. Finally, we calculate the x-ray magnetic circular dichroism spectra of Fe and Mn ions (L 2 and L 3 edges) in BFMO.
    Electronic ISSN: 2166-532X
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...