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The efficiency of spermatogenesis and the support capacity of Sertoli cells in Characiformes
(2017-11-01)
This stereological analysis of the types of germ cells and the number of Sertoli cells per cyst in Astyanax altiparanae testes during spermatogenesis is the first such report in Characiformes. Testes of 25 male A. altiparanae ...
Sphingomyelins and ceramides with very-long-chain PUFA are excluded from lowdensity, raft-like domains in differentiating spermatogenic cells
(American Society for Biochemistry and Molecular Biology, 2017-01-12)
Rat spermatogenic cells contain sphingomyelins (SM) and ceramides (Cer) with very long chain (VLC) PUFA, in nonhydroxylated (n-V) and 2-hydroxylated (h-V) forms. How these atypical species distribute among membrane fractions ...
Annual reproductive cycle of males of the flat-faced fruit-eating bat, Artibeus planirostris (Chiroptera: Phyllostomidae)
(2013-05-01)
Artibeus planirostris is an endemic species of Phyllostomid bat from the Neotropical region. Some studies have indicated that it exhibits seasonal bimodal polyestry; however, others postulate that it may be able to produce ...
Cytological identification and quantification of testicular cell types using fine needle aspiration in horses
(Equine Veterinary Journal Ltd, 2000-09-01)
Fifteen stallions of different breeds, age 3-11 years, had their right testicles evaluated by fine needle aspiration cytology (FNAC). Cytological analysis showed the following spermatogenic cell types: spermatogonia (1.6% ...
Morphological changes of mammalian nucleoli during spermatogenesis and their possible role in the chromatoid body assembling
(2012)
Chromatoid body (CB) is a typical cytoplasmic organelle of germ cells, and it seems to be involved in RNA/protein accumulation for later germ-cell differentiation. Despite most of the events in mammals spermatogenesis had ...
The process of differentiation during spermatogenesis in bees (Hymenoptera, apidae)
(1980-01-01)
The structural changes during spermatogenesis were studied on developing spermatogonia in drone testes of seven species of bees including the honeybee Apis mellifera and six other stingless bees. In view of the uniqueness ...
Duration of spermatogenesis in the bullfrog (Lithobates catesbeianus)
(Elsevier B.V., 2009-10-15)
The bullfrog (Lithobates catesbeianus) has substantial economic importance and has also been used as an experimental model for biological studies in the fields of pharmcology, medicine, and reproductive biology, especially ...
Structural alterations in the seminiferous tubules of rats treated with immunosuppressor tacrolimus
(Biomed Central Ltd., 2009-02-25)
Background: Tacrolimus (FK-506) is an immunosuppressant that binds to a specific immunophilin, resulting in the suppression of the cellular immune response during transplant rejection. Except for some alterations in the ...
Cytoplasmic bridges, intercellular junctions, and individualization of germ cells during spermatogenesis in Dermatobia hominis (Diptera: Cuterebridae)
(1996-02-01)
During mitotic and meiotic divisions in Dermatobia hominis spermatogenesis, the germ cells stay interlinked by cytoplasm, bridges as a result of incomplete cytokinesis. By the end of each division, cytoplasmic bridges flow ...
Structural characterization of nuclear phenotypes during Scinax fuscovarius spermatogenesis (Anura, Hylidae)
(2003-01-01)
In anuran amphibian Scinax fuscovarius, the spermatogenesis occurs in structures called seminiferous loculi, in which germ epithelium is organized in spermatocysts. Each cyst contains cells in the same stage of ...