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S D Denisov

Publications and source records attributed to S D Denisov.

5 recordsLinked to original sources
PubMed2006

Structure of the optic canal in human ontogenesis.

The aim of this work is to reveal the optic canal (OC) development regularities. It is of importance to identify the anatomical preconditions of tunnel syndrome and other pathologies of the OC. One hundred and five human embryos (195 OC, out of them 98 - left-hand, 97 - right-hand) from 4 up to 70 mm parietococcygeal length (PCL) have been studied. The diameters of the optic nerve (ON) and OC in its orbital, cranial apertures and middle part have been defined. In the same way the distances between the OC walls and the ON and ophthalmic artery have been measured. We have come to the conclusion that the morphogenesis of the OC walls is an asynchronous process. The development of the OC upper wall is retarded. Some asymmetry of the morphometric characteristics of the right and left OC has been revealed. The development of the OC depends on the organization of all its elements. The periods of the OC development have been identified. The OC constitutional features of its aperture form, the size of the OC walls and its apertures, ON size, the correlation between ON and OC diameters of the OC cranial and orbital apertures and "waist", and the arrangement of the OC compartments were revealed. The individual and typical features of the OC structure, revealed as a result of computer tomography (CT) analysis, account for CT effectiveness in the diagnosis of OC changes and the structures located in it.

Embryonic Development↗
PubMed1985

[Structure and homodynamia of the intersegmental connection TI-TII].

The reason to consider the second thoracic cerebrospinal nerve (Th2) as one of the sources of the brachial plexus is the fact of the intersegmentary connection between Th1 and Th2 by means of a neural branch situating on the internal surface of the thorax near the vertebral column (the intrathoracic or paravertebral branch). However, not all cases of the intersegmentary connection Th1-Th2 should be regarded only as participation of Th2 in the formation of the brachial plexus, this is conditioned by certain peculiarities of its structure and by the character of interconnections with the I intercostal nerve. The macro-microscopic method demonstrates that the intersegmentary connection Th1-Th2 includes somatic and vegetative components, that to the same extent participate both in formation of the brachial plexus and in the I intercostal nerve. The intersegmentary connection Th1-Th2 is considered as a vegetative neural structure, containing somatic conductors and is considered as a homologue of superficial connective branches. It is the way, by which sympathetic fibers can reach the brachial plexus from the segment situating below, without passing through the superior thoracic nodes of the sympathetic trunk.

Brachial Plexus↗
PubMed1985

[Structure of the tissue adjacent to the electrode in the case of an extremely low threshold of cardial electrostimulation].

The authors present the data of the histological structure of the dog heart tissue adjacent to the electrode tip following a ten-month period of electrical stimulation by means of an implanted graphited porous endocardial electrode and a pacemaker of the alternating polarity. The reason for performing such an histological investigation was an extremely low chronic threshold of heart electrostimulation, amounting to 0.35 V with the stimulus duration 1 ms. The structural features of the tissues as viewed by the authors, consist in (1) the thinning of the fibrous capsule of the electrode tip; (2) the presence of a zone adjacent to the electrode, with this zone being rich in the liquid component of the intercellular substance; (3) the formation of a conspicuous radix of the fibrous capsule, penetrating into the depth of the myocardium.

Animals↗
PubMed1983

[Thoracic vertebral nerve].

When studying phylogenetic transformations of the sympathetic trunk, a theoretical possibility has been substantiated that in Mammalia a caudal continuation of the vertebral nerve in the thoracic area can exist. By means of some embryological and anatomical methods, in man and in certain animals (cat, dog), together with the cervical, the thoracic vertebral nerve has been revealed. The latter has an appearance of a plexus situating on the rudimentary thoracic vertebral artery wall and is formed at the expense of the multisegmentary distribution of the gray connective branches fibers. Anatomical manifestation of multisegmentarity of the gray connective branches connections is a division of these branches into cranial and caudal fasciculi and their spreading in the foramens between the transversal processes of the thoracic vertebrae and the necks of the corresponding ribs. In Mammalia the neck and the thoracic vertebral nerves combine into the vertebral neural trunk homologous to the secondary sympathetic trunk in birds. The thoracic vertebral nerve is a roundabout way for innervation of many somatic and vegetative structures. The pathogenetic mechanisms responsible for disturbances in the cervical vertebral nerve function, probably, somehow influence the thoracic vertebral nerve.

Animals↗