In frog twitch muscle fibres, Na-octanoate (NaC8) shifted the relation between potassium induced tension and membrane potential to the right. The present study has been carried out to investigate the effect of this fatty acid on frog tonic fibres. Potassium contractures measured on bundles of 30-40 fibres of ileofibularis muscles were less decreased by NaC8 (2.5-10 mmol/l) than those of twitch ...

A number of studies have indicated that the relative toxicity of different fibre types after inhalation is related to their durability within lung tissue. The aim of this study was to assess the relative biopersistence of respirable para-aramid fibrils, chrysotile asbestos and code 100/475 glass fibres in rat lungs. The biopersistence of all three test fibres was measured by quantifying the cha...

Introduction Electromyography (EMG) is a useful and objective tool to obtain information about the muscle activity(1). A muscle consists of muscle fibres. The ends of the efferent nerves are connected to the muscle fibres through motor units. Every single motor unit serves several muscle fibres. An electrical impulse, traveling through the nerves and motor units, cause a depolarisation (contrac...

Previous studies investigating manufacture of phosphate-based glass fibres from glasses fixed with P2O5 content less than 50 mol% showed that continuous manufacture without breakage was very difficult. In this study, nine phosphate-based glass formulations from the system P2O5-CaO-Na2O-MgO-B2O3 were prepared with P2O5 contents fixed at 40, 45 and 50 mol%, where Na2O was replaced by 5 and 10 mol...

Electrical stimulation strategies for cochlear implants may be improved by studying temporal frequency coding in single auditory fibres and across fibres in acoustic stimulation [1]. In single nerve fibres, phase locking between action potentials and the acoustic stimulus can only be maintained at frequencies below 600 Hz. At these frequencies, the time interval between successive action potent...

Rabbit predominantly fast-twitch-fibre and predominantly slow-twitch-fibre skeletal muscles of the hind limbs, the psoas, the diaphragm and the masseter muscles were fibre-typed by one-dimensional polyacrylamide-gel electrophoresis of the myofibrillar proteins of chemically skinned single fibres. Investigation of the distribution of fast-twitch-fibre and slow-twitch-fibre isoforms of myosin lig...

In this study we investigated relationships between redox properties and biodurability of crocidolite asbestos fibres and three different man-made vitreous fibres (MMVF): traditional stone wool fibres (MMVF 21), glass fibres (MMVF 11) and refractory ceramic fibres (RCF). Each fibre type was incubated up to 22 weeks in four different incubation media: gamble solution (GS) pH 5.0 and pH 7.4, repr...

Plant fibres-cells with important mechanical functions and a widely used raw material-are usually identified in microscopic sections only after reaching a significant length or after developing a thickened cell wall. We characterized the early developmental stages of hemp (Cannabis sativa) stem phloem fibres, both primary (originating from the procambium) and secondary (originating in the cambi...

Mammalian skeletal muscle is an extremely heterogeneous tissue. Its diversity results from a spectrum of fibres which are metabolically suited to a wide range of functional demands. As judged from enzyme activity analyses of single fibres, the metabolic properties of fibres belonging to the same motor unit are similar or identical. It is likely, therefore, that the phenotype expression of muscl...

The paths taken by fibres regenerating to the tectum from various parts of the Xenopus retina were investigated in whole-mount preparations, after localized retinal labelling with HRP. The effects of different environments on the fibres were studied by comparing contralateral with ipsilateral regeneration, in the presence of the other eye or after it had been removed in embryonic life. Under al...