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排序方式: 共有867条查询结果,搜索用时 31 毫秒
861.
Montemayor Sara I. Besteiro Sebastián I. del Río M. Guadalupe 《Biodiversity and Conservation》2022,31(7):1969-1986
Biodiversity and Conservation - The Chaco and Pampean provinces in the Neotropical region are highly disturbed by intensive forestry and livestock raising. This study is an integrative approach... 相似文献
862.
Larissa Mayumi Bueno Dianelli Lisboa Caun Manuela Tosi Comelis Mateus Rodrigues Beguelini Sebastião Roberto Taboga Eliana Morielle-Versute 《Acta zoologica》2019,100(3):245-256
The Neotropical bat species Artibeus planirostris and Eptesicus furinalis present a different morphology of the female reproductive organs: the first presents a simplex uterus, while the second presents a bicornuate uterus, but there is no information about their ovaries. Our aim was to compare the general ovary morphology and the folliculogenesis process in these species to increase the knowledge about the reproductive diversity of tropical bats. We observed a morphological distinction between the ovaries of both species: A. planirostris presents the primordial follicles located in a cranial portion of the ovary and the interstitial gland cells are not distinctive, while in E. furinalis, the primordial follicles are located throughout the cortex, and there is an abundance of interstitial gland cells. Both species present binovular or triovular follicles. Artibeus planirostris is a monovular species, with a preferential ovulation in the left side. Some females of E. furinalis exhibited two corpora lutea in the same ovary, and others presented a corpus luteum in both right and left ovaries at the same time; thus, E. furinalis is a polyovular species. Our results express the variation between two Neotropical species, reflecting the great variation in the reproductive aspects in Chiroptera. 相似文献
863.
864.
Undecalcified bone fixed in a variety of fixatives and embedded in a new formulation of 2-hydroxy propyl methacrylate at 4 C has been sectioned at 1 to 5 microns. The embedding mixture contains 2-butoxyethanol as plasticizer and triethyleneglycol dimethacrylate as cross-linker. The accelerator was benzoyl peroxide and the catalyst was N,N-dimethylaniline. With proper embedding and care in sectioning it is possible to obtain sections with relatively little bone compression, excellent preservation of cellular elements, and a minimum of wrinkling. A wide variety of stains have been used for these sections and those reported here are Gill's hematoxylin-eosin, Nocht's azure-eosin, Feulgen, Hoechst 33258 (bisbenzimid H 33258), methyl green-pyronin, PAS, alizarin red, and von Kossa silver stain. There was excellent preservation of acid and alkaline phosphatase activities. A new method of prestaining immunofluorescent labeling was also applied to bone and examples of staining with anticollagen I and antifibronectin are presented. 相似文献
865.
Fracchia Sebastián Silvani Vanesa Flachsland Eduardo Terada Graciela Sede Silvana 《Mycorrhiza》2014,24(1):35-43
Aa achalensis is an endangered terrestrial orchid endemic from Argentina. In vitro symbiotic seed germination was evaluated for its propagation. Five different fungal strains were isolated from this species: two Rhizoctonia-like related to Thanatephorus cucumeris and three ascomicetaceous fungi belonging to Phialophora graminicola and one to an uncultured Pezizaceae. All five isolates promoted seed germination being one T. cucumeris strain the most effective. After 16 weeks of growth, 30 % of A. achalensis protocorms developed until seedlings with two/four leaves in this treatment. These findings open an opportunity to the knowledge and preservation of this species. 相似文献
866.
Llu��s Corominas G��rkan Sin Sebasti�� Puig Maria Dolors Balaguer Peter A. Vanrolleghem Jes��s Colprim 《Bioprocess and biosystems engineering》2011,34(2):205-214
The purpose of this paper is to refine the BIOMATH calibration protocol for SBR systems, in particular to develop a pragmatic
calibration protocol that takes advantage of SBR information-rich data, defines a simulation strategy to obtain proper initial
conditions for model calibration and provides statistical evaluation of the calibration outcome. The updated calibration protocol
is then evaluated on a case study to obtain a thoroughly validated model for testing the flexibility of an N-removing SBR
to adapt the operating conditions to the changing influent wastewater load. The performance of reference operation using fixed
phase length and dissolved oxygen set points and two real-time control strategies is compared to find optimal operation under
dynamic conditions. The results show that a validated model of high quality is obtained using the updated protocol and that
the optimization of the system’s performance can be achieved in different manners by implementing the proposed control strategies. 相似文献
867.
Claudio Muñoz Sebastián Gómez Talquenca Enrique Oriolani Mariana Combina 《Revista iberoamericana de micología》2010,27(2):66-70
BackgroundBotrytis cinerea is an ascomycete with a high genetic diversity and complex population structure, as reported from several hosts and sites. However, nothing is known about its genetic diversity in Argentina.AimsThe aim of this work is to estimate the genetic diversity of a local population of B. cinerea isolates obtained from grapevine in Argentina.MethodsIn this work, 35 strains that had been isolated from grapevines were genotyped for the presence of transposable elements and PCR-based RFLP molecular markers. The obtained results were compared with those from a large French population of the fungus, and used to perform a population genetics analysis using the Genepop software.ResultsAll the analysed isolates were classified as Group II (according to the most recent proposed classification) and showed a high degree of genetic diversity, with 14 different haplotypes. A significant difference in allele frequency was recorded between the local and French populations.ConclusionsThese comparisons between fungal populations, led to the detection of a high level of diversity and the differentiation between local and French groups of isolates. This was confirmed by an Fst value of 0.3332, which was higher than that reported for other pairwise comparisons of populations. This work constitutes the first report on the genetic diversity of B. cinerea isolates and their population structure in Argentina. 相似文献