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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 112 (1996), S. 112-118 
    ISSN: 1432-1106
    Keywords: Monosynaptic reflex ; H-reflex variability ; Fractal ; Supraspinal ; Spinal cord injury ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In our previous study, $${1 \mathord{\left/ {\vphantom {1 {f^\beta }}} \right. \kern-\nulldelimiterspace} {f^\beta }}$$ -type power spectrum with the spectral exponent β significantly greater than zero was found in the variability of soleus H-reflex amplitudes. This result indicated that the H-reflex variability was time-correlated owing to fractal characteristics. Furthermore, it was also suggested that the fractal characteristics were generated at the spinal level. The purpose of the present study was to investigate whether the fractal nature of the H-reflex variability was influenced by the loss of supraspinal input. Six healthy normal subjects and seven patients with spinal cord injury participated in this study. Soleus H-reflexes were evoked every l s from both legs simultaneously (stimulation intensity: motor threshold) and 1050 successive amplitudes of the H-reflex were recorded. The H-reflex sequence evoked from each leg was analyzed by “coarse graining spectral analysis” to calculate the spectral exponent β. The value of β was used to evaluate the level of time-correlation (fractal correlation). Cross-spectral analysis was used to evaluate the degree of synchronization between the H-reflex sequences evoked from both legs. The β values for normal subjects (0.84±0.33, left leg; 0.88±0.34, right leg) were significantly greater (P〈0.001) than those for patients (0.31±0.18, left leg; 0.32±0.14, right leg), suggesting that the H-reflex sequences for normal subjects were more time-correlated than for patients. In the frequency range less than 0.2 Hz, the coherence of both legs was high (0.41±0.14) for normal subjects as compared to 0.20±0.12 for patients (P〈0.005). In this frequency range, the phase was almost 0 rad for normal subjects, indicating that the H-reflex variabilities of both legs were synchronized. These results suggested that (1) the strong fractal correlation observed in the H-reflex sequences for normal subjects was associated with supraspinal input, and (2) such supraspinal input had equal influence on the reflex arcs of the soleus of both legs.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Mechanisms of Ageing and Development 62 (1992), S. 255-261 
    ISSN: 0047-6374
    Keywords: Aging ; DNA methylation ; Human ; Liver ; Spleen
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    European journal of applied physiology 57 (1988), S. 462-466 
    ISSN: 1439-6327
    Keywords: Reduced frequency breathing ; Hypoventilation ; Lactate removal ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of the present study was to investigate the blood lactate (LA−) responses to hypoventilation induced by reduced frequency breathing (RFB) during recovery from exercise. Five male subject performed 16 4 min cycling bouts alternating with 16 min rest periods. Exercise intensities were chosen at power outputs corresponding to 30% $$\dot V_{{\text{O}}_{{\text{2 max}}} } $$ at 2mMLA−, $$\dot V_{{\text{O}}_{\text{2}} } $$ at 4 mMLA−, and 90% $$\dot V_{{\text{O}}_{{\text{2 max}}} } $$ in each subject. Breathing frequency was voluntarily controlled starting 10 s before each 3rd min of exercise and maintained throughout the rest of the exercise period. Four different breathing patterns at each exercise intensity were used: normal breathing (NB), breathing every 4 s, breathing every 8 s, and maximal RFB. Except for the NB trials, subjects held their breath at functional residual capacity during each breathing interval. The concentration difference of LA− between the 3rd min sample and the 4th min sample was defined as the lactate change during exercise (Δ LA−ex), and that between the 4th min sample and the sample at the 3rd min after the end of the exercise as the lactate change during recovery (Δ LA−rec). An ANOVA showed significant (p〈0.05) differences in breathing procedures only in ΔLA−rec. ΔLA−rec seemed to increase as compared to NB only at $$\dot V_{{\text{O}}_{\text{2}} } $$ at 4 mMLA− and 90% $$\dot V_{{\text{O}}_{{\text{2 max}}} } $$ , while ΔLA−ex remained unchanged as compared to NB in spite of reduced ∵V A. These results might indicate that RFB inhibited lactate removal from working muscles during exercise.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 28 (1983), S. 3671-3679 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The novel reactive antioxidants based on tetrazoles that are stable at room temperature and convertible into the highly reactive nitrileimines by pyrolysis were prepared and the reactivity for carbon-carbon double bonds was evaluated. Antioxidants, i.e., 2-substituted phenyl-5-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)tetrazoles (PHPT) were prepared with the reaction of p-toluenesulfonylhydrazone of 3,5-di-tert-butyl-4-hydroxybenzaldehyde and substituted phenyl diazonium chloride in a mixed solvent of pyridine, ethanol, and water at -10°C to -20°C in 31-61% yields. To evaluate the reactivities of PHPT for carbon-carbon double bonds, m-chloro-substituted PHPT was pyrolyzed in an excess of styrene at 160-170°C for 0.5 h to give the 1-(3′-chlorophenyl)-3-(3″,5″-di-tert-butyl-4″-hydroxyphenyl)-5-phenyl-2-pyridazoline in a 44.1% yield by 1,3-dipolar addition reaction of the nitrileimine formed from the m-chloro-substituted PHPT. The thermogravimetric analysis of a mixture of proton isomer of PHPT and liquid polybutadiene showed that PHPT attached to liquid polybutadiene with an accompanying evolution of nitrogen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 89-98 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The chemical reactivities of novel reactive antioxidants based on tetrazoles for carbon-carbon double bonds of liquid polybutadiene and their antioxidation activities toward isoprene rubber were evaluated. These antioxidants, i.e., 2-substituted phenyl-5-(3′,5′ -di-tert-butyl-4′-hydroxyphenyl)tetrazoles (PHPT), were pyrolyzed in liquid polybutadiene at 160-170°C for 30 min to attach to rubber in extents of 61-85% of the nitrileimines formed from PHPT by 1,3-dipolar addition reaction. The reactivities of PHPT followed the order p-Cl 〉 m-Cl 〉 H 〉 p-CH3 〉 m-CH3, p-OC2H5, suggesting that PHPT reacts with diene rubber in electrophilic reaction and p-derivatives exhibit higher contents of binding than m-derivatives due to steric hindrance. From oxygen absorption data, the antioxidation activities of PHPT for isoprene rubber vulcanizates followed the order m-Cl, m-CH3 〉 H, p-Cl, p-Cl, p-CH3 〉 p-OC2H5. Isoprene rubber vulcanizates, obtained after pretreatment with PHPT by heating, were extracted with acetone, followed by aging to show that there was good retention and appreciable antioxidation activities of PHPT, especially, p-CH3 and p-Cl substituted PHPT.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 30 (1985), S. 4201-4201 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 29 (1991), S. 1197-1202 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monodisperse microspheres of poly(diethylene glycol dimethacrylate) with diameters in the size range 0.4-4.8 μm were prepared by the radiation-induced polymerization. Effects of solvent viscosity and monomer solubility were investigated for various kinds of solvents. The number of the nuclei, produced in the early stage of the polymerization, was found to be constant during the remainder of the polymerization. The nuclei grow to be monodisperse polymer particles without aggregation. This is attributed to the low mobility of the growing polymer particles.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 61 (1996), S. 351-358 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The amine functionalization of an acrylamide copolymer was achieved via Hofmann degradation. The starting material, poly(acrylamide-co-methyl methacrylate), was synthesized by radical precipitation polymerization. Using this copolymer, Hofmann degradation at 0°C in a water-dioxane mixture was done using sodium hypochlorite and NaOH. The resulting hydrogel could be dissolved in water-tetrahydrofuran mixtures, and the cast film had a water content of 73%. It was found that the conversion to primary amine was lower, and the extent of a side reaction was higher, compared to those of an acrylamide homopolymer. This was presumed to be due to the lack of the neighboring group effect among acrylamide units since it was a random copolymer. Further modification of this polymer by reacting the amine group is considered to obtain the desired properties for biomedical applications. © 1996 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 13 (1985), S. 191-202 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Recently there has been a growth of interest in the use of diaryliodonium salts (Ar2I+X-), triarylsulfonium salts (Ar3S+X-) and triarylselenonium salts (Ar3Se+X-) as photochemical initiator for cationic polymerizations. It is suggested by Ledwith that electron transfer to these cations results in fragmentation with the formation of aryl radicals and if the reducing species is a suitable free radical, a chain reaction for formation of cation will occur.We carried out radiation-induced polymerization of α-methyl-styrene in dichloromethane and bulk cyclohexene oxide in the presence of triphenyliodonium salt (C6H5)2 (I+PF-). Polymerization of these monomers was observed in the presence of these salts (G(-M)⋍ 1300), while no polymer was obtained in the absence of salts. Postpolymerization was negligibly small. This polymerization is considered to be initiated by the reaction of free radicals produced by radiation with cation salts and to proceed by cationic mechanism, since α-methylstyrene polymerized by ionic mechanism but hardly polymerizes by radical mechanism and this polymerization was suppressed in the presence of a small amount of water. The initiation mechanism of this polymerization was investigated by the use of pulse radiolysis technique.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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