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991.
Anew osteostracan genus and species,Victoraspis longicornualis n. gen., n. sp., is described based on material from Rakovets’, present day Ukraine. This new taxon shares characters with
the two generaStensiopelta
Denison, 1951 andZychaspis
Janvier, 1985. A phylogenetic analysis supports the position ofVictoraspis as the sister group to a monophyleticStensiopelta, while the interrelationships of the various species ofZychaspis are poorly resolved. A morphometric analysis is carried out in an attempt to further resolve the taxonomic affinity. This
analysis groups all examinedZychaspis species closely together, and further supports the establishment ofVictoraspis as separate genus.
相似文献
992.
Edgar E. Becerril-García Edgar M. Hoyos-Padilla Brad Henning Pelayo Salinas-De León 《Journal of fish biology》2020,97(4):1228-1232
The Revillagigedo Archipelago National Park is the largest no-take Marine Protected Area in North America and it is essential for the conservation of globally endangered marine megafauna, including cetaceans, sea birds and cartilaginous fishes. The present paper reports the occurrence of 28 chondrichthyan species, including 19 sharks, seven batoids and two chimaeras in the Revillagigedo Archipelago, comprising eight new records and a brief revision of confirmed species to date. 相似文献
993.
Bernat Gel Moreno Andrew M Jenkinson Rafael C Jimenez Xavier Messeguer Peypoch Henning Hermjakob 《BMC bioinformatics》2011,12(1):23
Background
The Distributed Annotation System (DAS) has proven to be a successful way to publish and share biological data. Although there are more than 750 active registered servers from around 50 organizations, setting up a DAS server comprises a fair amount of work, making it difficult for many research groups to share their biological annotations. Given the clear advantage that the generalized sharing of relevant biological data is for the research community it would be desirable to facilitate the sharing process. 相似文献994.
Ubiquinone in the lysosomal membrane fraction of rat liver 总被引:1,自引:0,他引:1
995.
996.
Utilization of d-carnitine by Pseudomonas sp. AK 1 总被引:2,自引:0,他引:2
Abstract The degradation of chlorophenols by Alcaligenes eutrophus JMP134 (pJP4) was studied. The strain grew on 2,4,6-trichlorophenol or 2,4,6-tribromophenol as the sole carbon and energy source. Complete degradation of 2,4,6-trichlorophenol was confirmed by chloride release and gas chromatography analysis of supernatants from growth cultures. The 2,3,5-, 2,3,4-, 2,3,6-and 2,4,5-isomers of trichlorophenol did not support growth. However, up to 40% of 2,4,5-trichlorophenol was mineralized during growth of A. eutrophus on chemostats fed with either phenol (0.4 mM) or 2,4,6-trichlorophenol (0.4 mM) plus 2,4,5-trichlorophenol (0.1 mM). Growth on 2,4,6-trihalophenols was also observed in A. Eutrophus JMP222, the strain lacking pJP4, suggesting that this new degradative ability reported for A. eutrophus is not related to pJP4 encoded catabolic functions. 相似文献
997.
Rohe M Carlo AS Breyhan H Sporbert A Militz D Schmidt V Wozny C Harmeier A Erdmann B Bales KR Wolf S Kempermann G Paul SM Schmitz D Bayer TA Willnow TE Andersen OM 《The Journal of biological chemistry》2008,283(21):14826-14834
Sortilin-related receptor with A-type repeats (SORLA) is a sorting receptor that impairs processing of amyloid precursor protein (APP) to soluble (s) APP and to the amyloid beta-peptide in cultured neurons and is poorly expressed in patients with Alzheimer disease (AD). Here, we evaluated the consequences of Sorla gene defects on brain anatomy and function using mouse models of receptor deficiency. In line with a protective role for SORLA in APP metabolism, lack of the receptor results in increased amyloidogenic processing of endogenous APP and in aggravated plaque deposition when introduced into PDAPP mice expressing mutant human APP. Surprisingly, increased levels of sAPP caused by receptor deficiency correlate with pro-found stimulation of neuronal ERK signaling and with enhanced neurogenesis, providing in vivo support for neurotrophic functions of sAPP. Our data document a role for SORLA not only in control of plaque burden but also in APP-dependent neuronal signaling and suggest a molecular explanation for increased neurogenesis observed in some AD patients. 相似文献
998.
999.
1000.
Hughes WO Pagliarini R Madsen HB Dijkstra MB Boomsma JJ 《Evolution; international journal of organic evolution》2008,62(5):1252-1257
Understanding the relative evolutionary importance of parasites to different host taxa is problematic because the expression of disease and resistance are often confounded by factors such as host age and condition. The antibiotic-producing metapleural glands of ants are a potentially useful exception to this rule because they are a key first-line defense that are fixed in size in adults. Here we conduct a comparative analysis of the size of the gland reservoir across the fungus-growing ants (tribe Attini). Most attines have singly mated queens, but in two derived genera, the leaf-cutting ants, the queens are multiply mated, which is hypothesized to have evolved to improve colony-level disease resistance. We found that, relative to body size, the gland reservoirs of most attines are similar in size but that those of the leaf-cutting ants are significantly larger. In contrast, the size of the reservoir did not relate with the evolutionary transition from lower to higher attines and correlated at most only slightly with colony size. The results thus suggest that the relationship between leaf-cutting ants and their parasites is distinctly different from that for other attine ants, in accord with the hypothesis that multiple mating by queens evolved to improve colony-level disease resistance. 相似文献