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1.
Izv Akad Nauk Ser Biol ; (5): 554-61, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10581871

RESUMO

Mathematical indices of the structure of the external surface of guard hairs have been developed on the basis of a KS300 system of automatic image analysis (Kontrom Elektronik, Germany), which are capable of serving, in some cases, as diagnostic parameters of large taxa (order, family). The guard hair morphology is affected by various factors, such as body region where a given hair is located, season, diet, sex of individual, and state of its health, which is expressed in changes of some morphometric data. For a more complete analysis of the characteristics of the guard hair structure, it is necessary to use indices that describe the macro- and microstructure of the external surface of the stem and its internal structure.


Assuntos
Animais Domésticos/classificação , Animais Selvagens/classificação , Cabelo/anatomia & histologia , Mamíferos/classificação , Animais , Animais Domésticos/anatomia & histologia , Animais Selvagens/anatomia & histologia , Desenho Assistido por Computador , Mamíferos/anatomia & histologia , Microscopia Eletrônica
4.
Izv Akad Nauk Ser Biol ; (2): 242-5, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10423934

RESUMO

The hamsters, Phodopus campbelli and Ph. sungorus have additional sacculi at the opening of the cheek pouches. The secretion of additional sacculi is very important for normalization of some aspects of the hamsters' physiology, as well as growth and development of pups, and also for chemical communication. We studied the role of the mother's additional sacculi secretion in mother-youngs interaction. It was shown that this secretion is most attractive for pups of both species from 6th to 11th day after the birth. During this period the pups begin to consume solid food but their own complexes only begin to form. Hence, pups may use the mother's additional sacculi as an additional (and may be the main) source of the secretion at this time. The difference in behavioral patterns of pups of the two studied species suggests some specific features of postnatal ontogenesis of additional sacculi.


Assuntos
Comunicação Animal , Mães , Mucosa Bucal/metabolismo , Odorantes , Phodopus/fisiologia , Olfato/fisiologia , Animais , Animais Recém-Nascidos , Bochecha , Cricetinae , Feminino , Especificidade da Espécie
9.
Izv Akad Nauk Ser Biol ; (4): 422-7, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9750429

RESUMO

Zonal trends of changes in animal population diversity on land are studied with the models of individual taxa and multispecies communities. Development of the transect method and use of different scale topoecological gradients make it possible to follow the succession of the species composition and topical preferences of individual species, as well as changes in their absolute and relative abundance, which lead to changes in the structure and pattern of functioning of the community as a whole. Modern methodological approaches concerning organization of complex studies on megatransects crossing several natural zones are analyzed. Methods of estimation of inter- and intrazonal changes in the animal population structure and diversity are discussed.


Assuntos
Animais Selvagens , Clima , Ecossistema , Animais , Animais Selvagens/classificação , Clima Frio , Clima Desértico , Dinâmica Populacional , Federação Russa
11.
Izv Akad Nauk Ser Biol ; (3): 369-73, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9644910

RESUMO

Studies were carried out on adult Djungarian hamster (Phodopus sungorus) males living in familial pairs under natural thermal and light regimes year-round. The response of hamsters to the odors of urine, secretory substances of the midabdominal gland and additional saccules in the ostium of cheek pouches, and faeces from conspecific males and females were studied. The results obtained suggest that the odors of urine and also feces play an important role in sexual recognition of individuals. These odors are especially attractive for the males in summer, during the period of active breeding. The tested males examined the odor of the midabdominal gland from individuals of the same sex reliably longer throughout the year, but in winter the interest in this odor was higher than in summer. These secretory substances appear to be important in organization of territorial interactions between individuals. The results of observations on breeding and the data on sex ratio in the broods from pairs with the tested males were compared to similar data obtained earlier for Roborovskii hamsters (Sokolov and Feoktistova, 1996). Similarities and differences were found in the course of breeding in the studied species.


Assuntos
Comunicação Animal , Odorantes , Phodopus/fisiologia , Reprodução/fisiologia , Estações do Ano , Animais , Cricetinae , Glândulas Exócrinas/metabolismo , Fezes , Feminino , Cor de Cabelo , Masculino , Comportamento Sexual Animal/fisiologia , Especificidade da Espécie , Urina
12.
J Invest Dermatol ; 110(6): 902-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9620297

RESUMO

Mutation of the hairless (hr) gene in mice causes severe abnormalities during the first hair follicle regression (catagen), resulting in complete baldness. Here, we further characterize how hairlessness develops in HRS/J hairless mouse skin (hr) by histology, histochemistry, immunohistology, and in situ hybridization. We show that, in hr skin, only two defined epithelial cell populations in the distal outer root sheath (ORS) retain their integrity, whereas the rest of the ORS disintegrates. The surviving distal ORS forms the characteristic utriculi, whereas the remnants of the bulge get isolated from other epithelial compartments, but retain the capacity to proliferate and to produce either columnar epithelial outgrowths or selected dermal cysts. Normal dermal papilla structures get lost during the development of hairlessness. Based on the patterns of keratin 17 mRNA and neural cell adhesion molecule antigen expression, and on the distribution of alkaline phosphatase activity, we propose that dermal cysts in hr skin arise from (i) the central ORS, (ii) bulge-derived cells, or (iii) the disintegrating proximal ORS under the influence of dermal papilla remnants. The hr mutation seems to disrupt the integrity of key functional tissue units in the hair follicle, possibly due to a dysregulation of normal, catagen-associated apoptosis and/or an impairment of cell adhesion, whereas the distal follicle epithelium (including its stem cell region) seems to be largely protected from this. Thus, hairless mice offer a unique model for dissecting the as yet obscure functional properties of the hr gene product in maintaining follicle integrity during normal catagen.


Assuntos
Cabelo/patologia , Camundongos Pelados/genética , Dermatopatias/etiologia , Fosfatase Alcalina/metabolismo , Animais , Feminino , Expressão Gênica/genética , Imuno-Histoquímica , Hibridização In Situ , Queratinas/genética , Antígeno Ki-67/genética , Camundongos , Camundongos Endogâmicos C57BL , Moléculas de Adesão de Célula Nervosa/genética , Fenótipo , RNA Mensageiro/análise , RNA Mensageiro/genética , Pele/química , Pele/enzimologia , Pele/patologia , Dermatopatias/genética , Dermatopatias/patologia
13.
Izv Akad Nauk Ser Biol ; (1): 37-46, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9542333

RESUMO

We studied the chromosome sets and specific morphological features and phenetic traits of hair cover coloration, as well the pattern of its inheritance upon experimental hybridization. The diploid set of chromosomes in the animals from the northern part of the range contains 2n = 58 (there are two additional B-chromosomes in the Far Eastern musk deer) and is identical to that from the southern musk deer forms. Discrete polymorphic features of neck and hair cover coloration have been identified in the northern and southern musk deer, and these are used as taxonomic features. A map illustrates distribution of the established subspecies.


Assuntos
Cervos/classificação , Animais , Cervos/genética , Diploide , Ásia Oriental , Feminino , Cor de Cabelo , Cariotipagem , Masculino , Fenótipo , Seleção Genética , Sibéria , Especificidade da Espécie
19.
Izv Akad Nauk Ser Biol ; (3): 287-96, 1997.
Artigo em Russo | MEDLINE | ID: mdl-9303753

RESUMO

We studied the histological structure of the adrenal glands within four months after extirpation of the midabdominal gland in newborn hamsters. Structural changes of the cells in all zones of the adrenal cortex suggest development of a compensatory reaction to the midabdominal gland extirpation. Hence, the midabdominal gland was a component of the complex of endocrine glands and synthesizes, in all likelihood, some precursors of steroid hormones and, thus, fulfilled both the exocrine and endocrine functions.


Assuntos
Glândulas Suprarrenais/anatomia & histologia , Glândulas Odoríferas/fisiologia , Animais , Animais Recém-Nascidos , Cricetinae , Phodopus , Glândulas Odoríferas/cirurgia , Fatores de Tempo
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