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P F Stepanov

Publications and source records attributed to P F Stepanov.

At least 19 recordsLinked to original sources
PubMed1989

[Age-related characteristics of the stromal-parenchymal relations of the human thymus].

In 155 thymuses and in 57 capsules of the organ, distributed according to 12 age groups, beginning from fetuses of 5 months up to 90 years, age transformations of stromal-parenchymatous relations of the human thymus have been studied and quantitatively estimated. During the postnatal ontogenesis the thymic capsule and its intraorganic connective, tissue frame together with the parenchyma undergo certain phase reorganizations, specific for each age period. The greatest development of the thymic connective tissue frame reaches at the age of 1-3 years and during sex maturation period. The thymic lymphoepithelial tissue exists during all age periods. In the thymic adipose body foci of extramedullary lymphopoesis are revealed, beginning from the first mature up to the elderly age.

Aging↗
PubMed1987

[Development of the uterine microcirculatory bed in postnatal ontogeny].

Age peculiarities of common structure of the microcirculatory pathways, specific volumes and amount of microvessels, zonal parameters of pericapillary microcirculation of metabolites, glycosamine glycans and glycoproteins contents, phosphatase and ATPase activity, collagen and elastic fibers of the microcirculatory bed vessels have been studied in 190 unchanged uteri, beginning from 36-week-old fetuses up to 35 years of age. The microcirculatory bed of myometrium during the period of postnatal ontogenesis investigated possesses a polymer-homonomous structural organization; its base make myoangiomas, including the terminal arteriole with precapillaries and collecting venule, that run from it. Similar structure of the myometrium microcirculatory pathways is already observed in fetuses of late antenatal period. In endometrium formed glanduloangionomas are revealed in the prepubertal age. Increase in glycosamine glycans contents is stated in the microvessel walls and in the uterine stroma during the process of its development. Compensatory-adaptive changes in the uterine microcirculatory bed are described during the newborn period up to the puberty. Functionally mature structures of the microcirculatory pathways in the submucosal and vascular layers of myometrium, endometrium and in the cervix uteri are found to be formed earlier than in other areas of the organ.

Adolescent↗
PubMed1985

[Method of microphoto exposure using the Sverdlovsk-4 photo exposure meter].

The exposure meter "Sverdlovsk-4" equipped with an adapting ring is recommended for determining the exposure in microphotography. The eyepiece of the exposure meter light-receiver together with the adapter is adjusted to the ocular of the camera viewfinder. The exposure is determined according to the operating instruction manual.

Photomicrography↗
PubMed1985

[Age and changes in the structure of the walls of the intrinsic arteries of the uterus].

By means of common histological, histochemical and morphometrical methods age changes in the cushion-like intimal protrusions of the intraorganic arteries have been studied in 176 uteri of women at all ages that died from trauma and other diseases which do not produce any changes in the uterus. Beginning from two years of age, in the uterus segmentary artery wall certain intimal thickenings are revealed; at this age they consist of immature fibrillar and cellular elements of the connective tissue and single myocytes. At the pubertal age an intensive development of the cushion-like protrusions is observed. The amount of myocytes in them increases at the expense of migration from muscular tunic of the vessel; they arrange chaotically. Then the structure of the elastic and collagenous carcass of the protrusions becomes more complex, the myocytes in them are oriented along the course of the artery, or along the sloping spiral. During adolescence and mature age, cyclic changes in the wall structure of the uterus intraorganic arteries are observed, depending on the phase of the menstrual cycle. During the second part of the proliferative phase, certain retruction of the protrusions is observed, and at the end of the secretion phase--maximal increase in their height. The intimal protrusions are specialized structures, playing an important role in ensuring an optimal blood circulation in the uterus during ovulation and in performing menstruation. Reverse development of these structures takes place in elderly and old age.

Adolescent↗
PubMedDate not supplied

[Age-related changes in large joints and long tubular bones of the upper extremity in children (echographic data)].

Two hundred and ten children at the age of 17 days up to 15 years have been examined. Echocameras, working in the grey scale regime have been used. At examination of the arm, forearm, brachial, elbow and radiocarpal joints in the children the most informative are longitudinal echographic approaches. At examination of the brachial bone head in the children older than 10 years only the anterior longitudinal approach is informative. To perform the echographic investigation of various elements of the locomotor apparatus of the upper extremities in children older than 9-10 years is difficult. The echographic reveal of additional nuclei of ossification and synostosis stages of the long tubular bones of the upper extremities in children often coincide in time with roentgenological data.

Adolescent↗