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1.
Ontogenez ; 33(2): 130-5, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11969073

RESUMO

The development of cytoarchitectonics of the brain rudiments in mammals is accompanied by the formation of an intracerebral vascular network. The relationship between these two processes is insufficiently clear. We studied the development of blood vessels and cytoarchitectonics in the neocortical rudiment of 6- to 13-week old human embryos. The light and electron microscopy methods were used, as well as histochemical visualization of NADPH-diaphorase in the vessel cells. The endothelium proliferation was evaluated using antibodies to proliferating cell nuclear antigen. Starting from week 8 of development, the tangentially oriented vessels formed a intraneural network in the ventricular zone of the rudiment, which appears to restrict the motility of neuroepithelial cells. The basal membrane was initially absent, and the neuroepithelial cells were in direct contact with the endothelial cells. During week 9 of development, the tangentially oriented vessels appeared in the intermediate zone. Formations similar to glial legs with short regions of the basal membrane adjoined the walls of inter- and intraneural vessels (note that, according to the published data, glial fibrillary acidic protein is not yet visualized at this stage). Angioarchitectonics depended little on the cell population density in different zones of the rudiment; specifically, the cortical plate did not contain tangentially oriented vessels until week 12-13 of development. The data we obtained suggest that the blood vessels fulfill a special morphogenetic function in the developing neocortex.


Assuntos
Neocórtex/citologia , Neocórtex/embriologia , Vasos Sanguíneos/embriologia , Feminino , Idade Gestacional , Humanos , Neocórtex/irrigação sanguínea , Neovascularização Fisiológica , Gravidez
3.
Morfologiia ; 117(2): 51-6, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10853252

RESUMO

Using light and electron microscopy the structure of blood vessels of neocortical anlage of human 7-12 embryos was studied. It was shown that at the early stage of formation of intraorgan vascular network the wall of blood vessels of ventricular zone successively differentiate, which is characterized by the appearance of second layer of cells (pericytes), accumulation of basement membrane components, widening of the zone of contacts between endotheliocytes and establishment of the contacts with bipolar cells of neocortex anlage. The morphological data obtained assist in comprehension of physiological aspects of formation of blood brain barrier and regulation of blood flow in human embryonal neocortex.


Assuntos
Neocórtex/irrigação sanguínea , Neocórtex/embriologia , Idade Gestacional , Humanos , Imuno-Histoquímica , Microcirculação/embriologia , Microcirculação/metabolismo , Microcirculação/ultraestrutura , Microscopia Eletrônica , Neocórtex/metabolismo , Neocórtex/ultraestrutura
4.
Morfologiia ; 116(4): 12-4, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10486801

RESUMO

Using silver nitrate impregnation nucleolar apparatus was studied in cells of ventricular zone of human neocortex in embryos at 6-13 wks of development. The number of nucleoli in cells grew gradually in the direction to ventricular surface in all cases studied. These data indicate characteristic localization of cell cycle phases in the neuroepithelium and correspond to the results of experiments performed in animals using DNA-labelled precursors. Specific cell population with scanty large nucleoli was found in inner portion of ventricular zone in 6-8 wks old embryos where mitotic figures are usually localized. Some hypotheses on these cells' origin and role are discussed.


Assuntos
Ventrículos Cerebrais/ultraestrutura , Neocórtex/ultraestrutura , Região Organizadora do Nucléolo/ultraestrutura , Ciclo Celular/fisiologia , Ventrículos Cerebrais/embriologia , Desenvolvimento Embrionário e Fetal/fisiologia , Células Epiteliais/ultraestrutura , Humanos , Neocórtex/embriologia
5.
Morfologiia ; 113(2): 53-7, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9621321

RESUMO

Human neocortex was studied using light and electron microscopy in embryos 6-10 wks of development. Vast majority of proliferating cells was established to be concentrated in ventricular zone. Nuclear, nucleolar and cytoplasmic organelle structure indicate various level of synthetic processes activity in cells of different layers of the developing human neocortex. The dynamics in nucleolar number in the cells of ventricular zone and cortical plate was demonstrated.


Assuntos
Neocórtex/embriologia , Região Organizadora do Nucléolo , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/embriologia , Desenvolvimento Embrionário e Fetal/fisiologia , Idade Gestacional , Humanos , Neocórtex/citologia
6.
Probl Endokrinol (Mosk) ; 39(5): 10-3, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8108337

RESUMO

Thyroid status was examined in 1214 children living in the Ulyanov district of the Kaluga region contaminated with radionuclides. Thyroid size and structure were assessed using ultrasonic examination, its function was characterized based on thyrotropin and free thyroxin measurements. Specific autoimmunity was evaluated from assays of antibodies to microsomal antigen and thyroglobulin. The resultant values were assessed with due consideration for the individual dose of 131I absorbed by the thyroid. Thyroid enlargement was detected in 21.2%, nodular goiter in 0.79% of the examinees. A reliable positive correlation was found between the degree of thyroid enlargement and 131I absorbed dose. Functional parameters (thyrotropin and free thyroxin) were within the normal range, no correlation was detected between hormonal parameters, thyroid size, and 131I absorbed dose. Antibodies to microsomal antigen were detected in 4.3%, to thyroglobulin in 7.2%, to both in 2.8% of the examinees, this being within the normal range in the population; but a relationship was detected between antibody production and absorbed dose of 131I. Hence, though no noticeable changes in the thyroid status were detected 5 years after the accident in the population examined, the revealed correlations between thyroid enlargement, presence of antithyroid antibodies, and 131I dose may be indicative of a possible growth of thyroid morbidity.


Assuntos
Saúde Ambiental , Poluentes Radioativos/efeitos adversos , Glândula Tireoide/patologia , Acidentes , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Reatores Nucleares , Federação Russa , Glândula Tireoide/fisiopatologia , Tireotropina/sangue , Tiroxina/sangue , Ucrânia
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