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ULTRASTRUCTURE OF THE HINNY (EQUUS-ASINUS X EQUUS-CABALLUS) SEMINIFEROUS EPITHELIUM
(Wiley-Blackwell, 1994-12-01)
The gonads and the germinative cells of 3 male hinnies were studied with light and transmission electron microscopy with the aim to observe the development of germ cells and verify the morphological modifications due to ...
Chromosome reduction in Eleocharis maculosa (Cyperaceae)
(Karger, 2008-01-01)
Chromosome numbers in Cyperaceae lower than the typical basic number x = 5 have been described for only three species: Rhynchospora tenuis (n = 2), Fimbristylis umbellaris (n = 3) and Eleocharis subarticulata (n = 3). ...
Ultrastructural analysis of the nucleolar aspects at spermiogenesis in triatomines (Heteroptera, Triatominae)
(Pergamon-Elsevier B.V. Ltd, 2010-10-01)
In this study the ultrastructural technique was used to analyze seminiferous tubule cells of the triatomine species Panstrongylus megistus, Rhodnius pallescens and Triatoma infestans. The data obtained provided evidence ...
Karyotypic diversification and its contribution to the taxonomy of Eleocharis (Cyperaceae) from Brazil
(CSIRO Publishing, 2010-01-01)
A karyotype analysis of 147 populations of 25 Brazilian species of Eleocharis (Cyperaceae) was carried out, including representatives of the three subgenera that occur in the country: Limnochloa, Scirpidium and Eleocharis. ...
Cystic proliferation of germline stem cells is necessary to reproductive success and normal mating behavior in Medaka
(2021-03-01)
The production of an adequate number of gametes is necessary for normal reproduction, for which the regulation of proliferation from early gonadal development to adulthood is key in both sexes. Cystic proliferation of ...
Follicular environment and oocyte maturation: roles of local peptides and steroids
(Brazilian Coll Animal Reproduction, 2017-07-01)
A large amount of data on the mechanisms regulating cumulus-oocyte maturation in mammals has been generated in the last 20 years. It has been made clear that oocyte-secreted factors play a central role in the control of ...
Presence of chromatoid bodies in the Rhodnius genus detected by cytochemical analysis
(Funpec-editora, 2016-01-01)
In addition to the epidemiological importance regarding the transmission of Chagas disease, triatomines are also important biological models for cellular studies, because they have holocentric chromosomes, post-reductional ...
Oocyte maturation in bitches
(Brazilian Coll Animal Reproduction, 2012-07-01)
The canine species has been used as an experimental model for preservation of endangered species. Biotechnologies of reproduction, such as in vitro maturation (IVM), have been used to meet this objective. Several protocols ...
Neometrypus badius a new species of cricket with an unusual sex determining mechanism (Grylloidea, Eneopteridae, Tafaliscinae, Neometrypini)
(2001-06-01)
A new species of the genus Neometrypus collected in Cardoso Island in the Atlantic littoral of São Paulo State is described. The species is 2n=14 (male) - 14 (female) with a neoXY-XX sex determining mechanism originated ...
Further Evidence of Chromosome Abnormalities in Normal and Haploid Gynogenetic Progenies of Rainbow Trout, Oncorhynchus mykiss
(1996)
Gynogenetic haploid progenies of rainbow trout, produced using UV light for sperm
inactivation, were studied in comparison with normal progenies. In a total of 437 normal embryos,
3.5% of them showed chromosome abnormalities: ...