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1.
Brenda Díaz‐Crdenas Eduardo Ruiz‐Sanchez Hctor Gadsden Jos Manuel García‐Enriquez Patricia Castro‐Felix Gamaliel Castaeda‐Gaytn Anne Santerre 《Journal of Zoological Systematics and Evolutionary Research》2019,57(4):864-876
The biogeographic history of the Chihuahuan Desert is known to be complex, and there is evidence of the effects of physiographic and climatic events in species diversification and demographic population changes in many taxa. Here, using DNA sequence data, we studied the influence of the physiographic and climatic events that occurred in the Chihuahuan Desert during the Pliocene–Pleistocene transition on the speciation and evolutionary history of the sister lizard species Sceloporus cyanostictus and S. gadsdeni. First, based on mtDNA and nDNA sequences, we estimated the divergence times of the sister species. Then, based on mtDNA sequences, we investigated the demographic history of both species within a phylogeographic framework. The divergence time was inferred to be 1.48 Mya, date that corresponds to the existence of a large lake in the Mapimian subprovince, between the current geographic locations of S. cyanostictus and S. gadsdeni. This lake could have acted as a barrier, leading to the speciation of both species. For the demographic history of the two species, we identified two distinct patterns: the population expansion of S. gadsdeni within the Last Glacial Maximum and the potential population decline of S. cyanostictus. Our results can be used as a guide for the study of other aspects that could be critical to developing conservation actions that ensure the survival of not only S. gadsdeni and S. cyanostictus, but also other co‐occurring lizard species. 相似文献
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P. Cruz C. H. Mejia‐Ruiz R. Perez‐Enriquez A. M. Ibarra 《Molecular ecology resources》2002,2(3):239-241
Five polymorphic microsatellite loci were characterized for Penaeus (Litopenaeus) vannamei. Loci were isolated using a partial Sau3A1 genomic library by the sequencing of randomly selected clones and by a biotinylated (CT)10 and (GT)10 probes screening procedure. The last strategy resulted in the most useful data. About 40% of the clones showed a previously reported satellite/microsatellite (PVS1), reducing the chance of finding new microsatellite regions. Whereas two of the microsatellite loci with more than 10 alleles will be useful for mating analysis in a breeding program, the others might prove useful for population genetic studies. 相似文献
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R. Borges-Argez L. Balnbury A. Flowers A. Gimnez-Turba G. Ruiz P.G. Waterman L.M. Pea-Rodríguez 《Phytomedicine》2007,14(7-8):530-533
A number of flavonoids isolated from Lonchocarpus spp. were evaluated for their antiprotozoal and cytotoxic activity. Flavone 6 and chalcone 7 were found to be the most active against Leishmania parasites and against cell cultures of Leukemia P388DI and adenocarcinoma prostate PC-3. 相似文献
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Javier Ruiz Lilia Montoya Valle López Ricardo Amils 《Origins of life and evolution of the biosphere》2007,37(3):287-295
Europa’s chaos and lenticulae features may have originated by thermal diapirs related to convective plumes. Warm ice plumes
could be habitable, since their temperature is close to the ice melting temperature. Moreover, thermal plumes intruding into
the lower stagnant lid warm several kilometers of country ice above 230 K for periods of 105 years, and hundreds of meters above 240 K for periods of 104 years. Diapir coalescence generating chaos areas should provide a large zone with temperature above ∼240 K for thousands
of years. A temperature above ∼230 K is potentially interesting for astrobiology, since it corresponds to the lowest temperature
at which microbial metabolic activity in Antarctic ice has been reported. So, the warming by thermal plumes could cause an
aureole of biological activation/reactivation in the country ice. Adaptation of life to either high salinity or low temperature
is similar: it requires the synthesis of compatible solutes, like trehalose or glycerol, which are efficient cryoprotectants.
We therefore propose that the future astrobiological exploration of Europa should include the search for compatible solutes
in chaos and lenticulae features. 相似文献
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The diversity of the genus Mantisalca in southwest Europe is the subject of much controversy. The present taxonomic revision of the genus on the Iberian Peninsula allows four species to be recognized, whose morphological variability is described and various synonyms are typified. A new species is described, M. cabezudoi Ruiz de Clavijo and Devesa, endemic to southeast Spain. The name Microlonchus spinulosus Rouy is reinstated for a species endemic to the central and east Iberian Peninsula, for which a new combination is made: Mantisalca spinulosa (Rouy) Ruiz de Clavijo and Devesa. A diagnostic key to the taxa is given. 相似文献
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J Reig C Jiménez A Jornet C Ruiz de Miguel M Petit 《Acta morphologica Neerlando-Scandinavica》1988,26(4):239-248
A case of a single coronary artery is described in a 50-year-old male, who died of asphyxia. The artery originated in the right aortic sinus and from it another artery emerged which crossed the crista supraventricularis and the interventricular septum and returned to occupy a subepicardial position in the lower half of the anterior interventricular sulcus. This partially intramyocardial artery was considered as the anterior interventricular artery. A literature survey showed only five cases with similar characteristics. The importance of this anomaly derives from the risk of damage occurring to the intramyocardial artery during a manipulation of the infundibulum of the right ventricle in a cardiac surgery or from problems of perfusion during coronary bypass procedures. 相似文献