Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “fiber”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMedDate not supplied

Experimental investigations in prolonged myocardial ischaemia. Note I. Biology of the myocardial fiber after transient myocardial fiber after transient myocardial ischaemia.

The first ten days' evolution of post-ischaemic lesions of the premonitory or angina pectoris syndrome type was experimentally studied by the challenge of a short-term (10 and 15 min) ischaemia, of an adaptation to ischaemia and an adaptation followed by prolonged ischaemia (20 and 35 min). Worthy of note was the persistence of reversible lesions after short-term ischaemia and adaptation, and the progressive evolution towards cytolysis and cicatrization of some pancicellular foci after adaptation followed by prolonged ischaemia. The role of mitochondrial lesions, of lysosomal hydrolases, the inefficiency of renewed circulation, as well as problems of diagnosis are discussed.

Angina Pectoris↗
PubMed1983

Growth of fiber types and apparent fiber number in skeletal muscle of broiler- and layer-type chickens.

Proportions of myofiber types, radial growth (diameter) of myofibers and apparent myofiber number were measured at the midsection of the sartorius muscle of broiler- and layer-type chickens. Broiler birds grew mor rapidly than layer birds so that in comparisons at equal age, broilers had heavier body and muscle weights, larger diameter type I and II myofibers and greater apparent myofiber number. The proportion of type II red myofibers decreased and that of type II white myofibers increased during growth. These changes occurred at a younger age in broiler-type birds. At equal body weights, however, broiler- and layer-type birds had similar proportions of the various myofiber types, which indicates that development of myofiber types is affected by functional demands on skeletal muscle related to increasing body weight. At equal body weights, broilers had larger diameter type II myofibers than layers and had a more rapid rate of type II myofiber radial hypertrophy during growth. In contrast, layer-type birds had larger type I myofibers than did broilers and the rate of radial growth was similar between breeds. Apparent myofiber number per unit of body weight increased during growth at a similar rate in the two types of birds but broilers had greater numbers of myofibers. It was concluded that more rapid growth and greater muscularity of broiler-type birds are caused by more rapid myofiber hypertrophy and the presence of more myofibers. It is suggested that selection for growth and muscularity favors factors that promote selective radial hypertrophy of type II myofibers as seen in broiler-type chickens.

Animals↗
PubMed1981

[Diffusion of fluorescein molecules in muscle fiber. II. The ratio of the coefficient of diffusion to the fiber diameter].

The diffusion of sodium fluorescein was studied upon alteration of the medium tonicity and the fibre stretching. In the former case, coefficients of both translational (Dt) and of rotational (Dr) diffusion changed, but not equally. With a decrease of the fibre diameter on hypertonia, Dt is reduced more drastically than Dr, which means that the diffusion anisotropy (see formula in text) is diminished. On stretching muscle fibres, provided their volumes are constant, the diffusion rate is not changed. It is concluded that the surface-ordered water in muscle fibre capillaries, in which dye molecules are diffusing, becomes desorganized in the process of hypertonic contraction due to the increase of ionic concentration (potassium, for the most time).

Animals↗
PubMed1976

[Wolff-Parkinson-White syndrome caused by association of atrio-hisian fibers and Mahaim's fibers. Comparison between the electrophysiology and histology].

A child of six who had had several losses of consciousness died suddenly during a spell of tachycardia. The EKG showed at times a type B Wolff-Parkinson-White syndrome, at times a Lown-Ganong-Levine syndrome. Intracavitary electrophysiological explorations had been carried out. The interest of this case lies in the comparison between these electrophysiological explorations and the histological examination of the normal and accessory conduction pathways. The short PR interval, which did not lengthen under the effect of premature atrial stimulation, was accounted for by the presence of atrio-His bundle tracts. The intermittent delta wave was due to Hissio-ventricular Mahaim fibres. These two accessory conduction pathways are considered as abnormal.

Child↗