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  • 1
    Electronic Resource
    Electronic Resource
    The influence of pelvic nerve transection on the neuromuscular system of the canine urinary bladder (1992)
    Springer
    Urological research 20 (1992), S. 45-48 
    Details
    ISSN: 1434-0879
    Keywords: Decentralized bladder ; Low-pressure bladder ; Trans-synaptic degeneration ; Denervation supersensitivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We previously reported that bladder overdistension led to denervation and subsequent supersensitivity of the detrusor muscle to acctylcholine. Therefore, to exclude the influence of bladder overdistension, we produced a low-pressure bladder in female mongrel dogs using an indwelling urethral catheter, and performed pelvic neurectomy (decentralization). We examined the effects of decentralization on the neuromuscular system of the bladder. The contraction response levels of bladder strips in dogs 1 and 2 weeks after neurectomy was low, and significantly different from that of bladder strips in the control group. The doseresponse curves of dogs 4 and 8 weeks after neurectomy showed a shift to the left when compared to those of the control group, indicating a significant increase in sensitivity of the bladder strips. Many cholinergic terminal and varicosity profiles had a normal ultrastructure in all of the groups subjected to neurectomy, while some had degenerating profiles representing clear axoplasm without any recognizable organelles. Microphotographs of bladders obtained from dogs with spontaneous catheter loss showed degenerating axons, which were observed more frequently than in bladders kept empty with indwelling urethral catheters. Micturition in the dogs with spontaneous catheter loss was achieved by overflow incontinence without catheterization. These findings suggest that post-synaptic nerve degeneration may be augmented by impairment of micturition, followed by decentralization. Our observations also suggest that post-synaptic nerve degeneration (denervation) plays an important role in the increased sensitivity of the detrusor muscle to acetylcholine in the parasympathetically decentralized urinary bladder, whether denervation is due to trans-synaptic degeneration or impairment of micturition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00294334
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  • 2
    Electronic Resource
    Electronic Resource
    The response of the detrusor muscle to acetylcholine in patients with infravesical obstruction (1991)
    Springer
    Urological research 19 (1991), S. 117-121 
    Details
    ISSN: 1434-0879
    Keywords: Bladder overdistension ; denervation supersensitivity ; detrusor instability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We previously examined the effects of overdistension on the neuromuscular system of canine urinary bladders and reported that bladder overdistension led to nerve degeneration and subsequent supersensitivity through a decrease of blood supply to the bladder. We have accordingly in this study evaluated these changes in human subjects with infravesical obstruction. The responses to acetylcholine of bladder strips obtained from patients with detrusor instability were not significantly different from those of bladder strips from patients without detrusor instability, but the dose-response curve of these groups showed a shift to the right compared to that of the unobstructed control patients. As compared with the response of bladder strips in patients without an episode of retention, the response in patients who received prostatectomy within 30 days demonstrated no significant difference, although in patients who received prostatectomy after more than 30 days there was a statistical difference. These results indicated a significant decrease in sensitivity of the detrusor muscle in patients with infravesical obstruction and suggest that bladder overdistension caused by infravesical obstruction may lead to supersensitivity of the detrusor muscle secondary to denervation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00368187
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  • 3
    Electronic Resource
    Electronic Resource
    Effect of tumour necrosis factor in the mouse-tail model of psoriasis (1990)
    Springer
    Archives of dermatological research 282 (1990), S. 459-462 
    Details
    ISSN: 1432-069X
    Keywords: Tumour necrosis factor ; Mouse tail epidermis ; Granular layer ; Keratinocytes ; Psoriasis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of local and systemic administration of tumour necrosis factor (TNF) on the mouse-tail model of psoriasis were examined histologically at 4 days after administration. Subcutaneous injection of TNF at 1×101 to 1×104 units/mouse resulted in dose-dependent formation of a granular layer in the tail scales, which was quantified as the percentage of tail scales having granular layer formations extending over half or more of their surface and was larger than that occurring in untreated mice and in mice receiving injections of vehicle solution alone. Daily intraperitoneal injection of TNF at 1×103 or 1×104 units/mouse for 28 days resulted in similar granular layer formation and in a significantly reduced mitotic index of the tail keratinocytes, indicating an antiproliferative effect of TNF. The lowered mitotic index and the induction of granular layers, apparently attributable to a modulation of keratinocyte proliferation and differentiation by TNF, suggest that TNF may be effective as a drug for treatment of psoriasis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00402623
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  • 4
    Electronic Resource
    Electronic Resource
    An analysis of postsynaptic potentials of tectal neurons of the frog: correlation with impulses recorded from the terminals of retinotectal afferents (1988)
    Springer
    Experimental brain research 70 (1988), S. 429-432 
    Details
    ISSN: 1432-1106
    Keywords: Optic tectum ; Frog ; Monosynaptic activation ; “On-off” retinal fiber ; Pulse-analogue correlation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of this study is to examine the synaptic action between terminals of retinal ganglion cell axons and tectal neurons. To accomplish this, an extracellular single unit identified as retinotectal fiber was first isolated from the superficial layer of the optic tectum and intracellular responses were recorded from a tectal neuron in the vicinity of the extracellular recording electrode. “On-off” retinal fibers and both E-E (EPSP at “on” and “off” of diffuse light) and EI-EI type (EPSP-IPSP combination at “on” and “off” of diffuse light) tectal neurons were selected for the pre- and postsynaptic pair. Postsynaptic responses to a small moving square were averaged by triggering with the isolated presynaptic impulses. The latency of the resultant EPSPs indicated that most of the E-E and EI-EI type tectal neurons were monosynaptically activated by “on-off” retinal fibers. One of the E-E type tectal neurons was identified as a large ganglionic neuron in layer 8.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00248367
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  • 5
    Electronic Resource
    Electronic Resource
    Effects of the SiC/Al interface reaction on fracture behavior of a composite conductor using SiC fiber reinforced aluminum for next generation power equipment (1999)
    Springer
    Journal of materials science 34 (1999), S. 1583-1593 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Electrical power demands are increasing every year, meaning that lightweight electric cable is needed which has high transmission capacity, high thermal resistance and low sag. Tokyo Electric Power Co., Chubu Electric Power Co. and Hitachi Cable Ltd. have been breaking new ground in the field of electric cable through the development of a SiC fiber reinforced aluminum conductor. In this work, the SiC/Al interface reaction during the manufacturing process and the electricity transmission temperature were studied by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and field emission-Auger electron spectroscopy (FE-AES) for long-term reliability assessment. No reaction products were detected at the SiC/Al interface of elemental wire consisting of 7 SiC/Al preformed wires, indicating that the wire manufacturing process was reliable. An Al4C3 product was detected locally at the SiC/Al interface of the wire which had been thermally treated in molten Al under unfavorable conditions. The activation energy, Q, of Al4C3 growth at the SiC/Al interface was about 190 kJ/mol. In the temperature range of electricity transmission, Al atoms diffused into SiC fiber during heat treatment, and the amount of the diffused Al increased with increasing treatment temperature and holding time. The activation energy of Al diffusion through the SiC/Al interface to SiC fiber was about 78 kJ/mol. Strength deterioration was not induced by Al diffusion into SiC fiber, but strength strongly depended on the formation of Al2SiO5 compound at the SiC/Al interface above 400°C transmission temperatures. Kinetics calculations indicated that the rate of strength deterioration of the composite cable, held at 300°C for 36 years, was about 5%, so that practical use of SiC/Al composite cable should not be far in the future.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1004524516143
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  • 6
    Electronic Resource
    Electronic Resource
    Influences of Fe-impurity on the production process of SiC fiber reinforced Al for electric cables (1999)
    Springer
    Journal of materials science 34 (1999), S. 1573-1582 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract As electrical power demands increase every year, the need becomes stronger for light weight electric cables which have high transmission capacity, high thermal resistance and low sag. We have developed a SiC fiber reinforced aluminum electrical cable to meet this need. Mechanical properties of the SiC/Al composite conductor are very susceptible to iron impurity which becomes mixed in the Al matrix during manufacture of the composite conductor. In this work, we studied the effects of Fe impurity in Al on fracture behavior of the composite conductor. A preformed wire was prepared by dipping a bundle of 1500 pieces of SiC fiber (Si: 63.7, C: 35.8, O: 12.3 mass %) into molten Al in which 0.36 mass % Fe and 0.5 mass % Ti were mixed. The Ti was added to improve the wetting property. Test samples were prepared by bundling seven preformed wires together. A tensile test was carried out for the composite conductor, and pull-out behavior of SiC fiber at the fracture surface was observed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and electron probe micro analysis (EPMA). Pull-out of SiC fiber was observed at the fracture surface of the composite conductor using Fe-free Al. However, pull-out of SiC fiber was not observed at the fracture surface of the composite conductor using Fe-containing Al since Al was combined inseparably with the SiC and Fe. The fracture origin of the Fe-containing sample was a precipitated Fe-compound at the SiC/Al interface. Tensile strength of the Fe-containing sample was a half of that of the Fe-free sample. We propose the following the precipitation mechanism for the Fe compound. In manufacturing of the preformed wire, molten Al solidifies from the surface to the SiC/Al interface because of the low thermal conductivity of the SiC fiber. In the cooling process, Fe-free Ti-compound precipitates in the molten Al by a peritectic reaction. This leads to a higher concentration of Fe in the molten Al near the interface, and finally, FeAl3 compound precipitates at the SiC/Al interface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1004572415234
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    Paper (German National Licenses)
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