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Functional and topographical properties of field potentials evoked in rat dorsal horn by cutaneous C‐fibre stimulation.

Extracellular field potentials in the lumbosacral dorsal horn evoked by stimulation of cutaneous C fibres in the sural nerve were explored in the halothane‐anaesthetized rat. C‐fibre‐evoked field potentials were prominent in lamina II and lamina V of the dorsal horn. These potentials had a latency of 80‐130 ms and a duration of more than 200 ms. A peak in the C‐fibre‐evoked field potential, termed

Cutaneous inputs to dorsal horn neurones in adult rats treated at birth with capsaicin

Single unit electrical activity has been recorded from dorsal horn neurons in the lumbar spinal cord of adult rats which had been treated at birth with either capsaicin (50 mg kg-1) or with the solvent-vehicle only. The responses of these neurones to electrical stimulation of A- and C-fibres in the sural nerve and to natural stimulation of their cutaneous receptive fields have been studied. In veh

Activity evoked by A- and C-afferent fibers in rat dorsal horn neurons and its relation to a flexion reflex

The responses of 56 neurons recorded in the lumbosacral spinal cord of halothane-anesthetized rats were studied following the application of mechanical stimuli to the skin on the lateral aspect of the paw or electrical stimulation of the sural nerve. Only neurons driven by A- and C-fiber stimulation were considered. The evoked activity in a nerve supplying flexor muscles, the common peroneal nerve

Segmental action of morphine and acupuncture-like stimulation in the dorsal horn of the rat as visualized by the 14C-2-deoxyglucose method

It is not clear where analgesic measures such as morphine and acupuncture have their sites of action. Since analgesia from acupuncturelike stimulation is reversed by naloxone (Sjolund and Eriksson, Brain Res. 173:295, 1979) it is probably mediated via endorphins. The two analgesic procedures mentioned may thus use similar inhibitory mechanisms. We now present data from autoradiographic measurement

Intrathecally applied morphine inhibits nociceptive C fiber input to the primary somatosensory cortex (SI) of the rat

Nociceptive C fiber input to SI in the halothane-nitrous oxide anesthetized rat was assessed by recording cortical field potentials evoked by noxious thermal cutaneous stimulation with CO2-laser pulses. Morphine topically applied onto the lumbar spinal cord produced a dose-dependent inhibition of nociceptive C fiber input from the hind paw to the contralateral SI. The inhibitory effect of morphine

Site of action of antinociceptive acupuncture like nerve stimulation in the spinal rat as visualized by the 14C-2-deoxyglucose method

Aim: It has been claimed that supraspinal structures are necessary forthe depression of nocifensive behaviour elicited by acupuncture or acupuncturelike (AL) stimulation. However, nocifensive reflexes in the spinal catwere inhibited for long periods by a mechanism releasing opieids on AL conditioning stimulation of groups II-III muscle afferents (Sj~lund and Eriksson, Neurosci.Lett. S3:264:1979).

Modular organization of spinal nociceptive reflexes : A New Hypothesis

Recent experimental studies suggest that the nociceptive withdrawal reflex system essentially has a "modular" organization, with each module concerned with the control of a single or a small group of muscles. This organizational principle appears to apply also to some spinoolivocerebellar pathways.

Convergence of afferent paths to olivo cerebellar complexes.

It is now well documented that the cerebellar cortex is divided into sagittal zones which can be identified by their climbing fibre inputs from specific regions of the inferior olive. Each cortical zone sends its efferent fibres, the Purkinje cell axons, to a separate group of neurones in the cerebellar or vestibular nuclei (Oscarsson, 1980, Voogd and Bigare, 1980, Voogd, 1982, Trott and Armstrong

Generisk valideringsmodell för bedömning av reell kompetens för tillgodoräknande som högskoleutbildning (GVTH) samt valideringskriterier för socionomexamen

Denna forskningsrapport sammanfattar resultaten från en studie bedriven inom ramen för Pilotverksamheten för bedömning av reell kompetens (REKO) under ledning av Universitets- och Högskolerådet (UHR). I studien utvecklas:• en generisk valideringsmodell för bedömning av reell kompetens för tillgodoräknande som högskoleutbildning. Valideringsmodellen (av både summativ och formativ karaktär) ska kunn

Fracture toughness of a laminated composite

The fracture toughness of a polymer-metal laminate composite is obtained by mechanical testing of a specimen containing a pre-crack. The laminate is a material used for packaging. It consists of a thin aluminium foil and a polymer coating. A centre cracked panel test geometry is used. Each of the layers forming the laminate is also tested separately. The result is compared with the measured fractuThe fracture toughness of a polymer-metal laminate composite is obtained by mechanical testing of a specimen containing a pre-crack. The laminate is a material used for packaging. It consists of a thin aluminium foil and a polymer coating. A centre cracked panel test geometry is used. Each of the layers forming the laminate is also tested separately. The result is compared with the measured fractu

A model for graded materials with application to cracks

Stress intensity factors are calculated for long plane cracks with one tip interacting with a region of graded material characteristics. The material outside the region is considered to be homogeneous. The analysis is based on assumed small differences in stiffness in the entire body. The linear extent of the body is assumed to be large compared with that of the graded region. The crack tip, incluStress intensity factors are calculated for long plane cracks with one tip interacting with a region of graded material characteristics. The material outside the region is considered to be homogeneous. The analysis is based on assumed small differences in stiffness in the entire body. The linear extent of the body is assumed to be large compared with that of the graded region. The crack tip, inclu