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151.
Sashrika Pillay Adhil Bhagwandin Mads F. Bertelsen Nina Patzke Gerhard Engler Andreas K. Engel Paul R. Manger 《The Journal of comparative neurology》2021,529(1):8-27
Employing cyto‐, myelo‐, and chemoarchitectural staining techniques, we analyzed the structure of the hippocampal formation in the banded mongoose and domestic ferret, species belonging to the two carnivoran superfamilies, which have had independent evolutionary trajectories for the past 55 million years. Our observations indicate that, despite the time since sharing a last common ancestor, these species show extensive similarities. The four major portions of the hippocampal formation (cornu Ammonis, dentate gyrus, subicular complex, and entorhinal cortex) were readily observed, contained the same internal subdivisions, and maintained the topological relationships of these subdivisions that could be considered typically mammalian. In addition, adult hippocampal neurogenesis was observed in both species, occurring at a rate similar to that observed in other mammals. Despite the overall similarities, several differences to each other, and to other mammalian species, were observed. We could not find evidence for the presence of the CA2 and CA4 fields of the cornu Ammonis region. In the banded mongoose the dentate gyrus appears to be comprised of up to seven lamina, through the sublamination of the molecular and granule cell layers, which is not observed in the domestic ferret. In addition, numerous subtle variations in chemoarchitecture between the two species were observed. These differences may contribute to an overall variation in the functionality of the hippocampal formation between the species, and in comparison to other mammalian species. These similarities and variations are important to understanding to what extent phylogenetic affinities and constraints affect potential adaptive evolutionary plasticity of the hippocampal formation. 相似文献
152.
Cornelia Speth Gerhard Blum Magdalena Hagleitner Caroline Hörtnagl Kristian Pfaller Beate Posch Helmut Werner Ott Reinhard Würzner Cornelia Lass-Flörl Günter Rambach 《Medical microbiology and immunology》2013,202(5):379-389
Aspergillus terreus-induced invasive infections exhibit high lethality, partly due to the intrinsic resistance for amphotericin B (AmB). We compared the virulence and pathogenesis of an AmB-resistant isolate of A. terreus (ATR) with that of a rare variant showing enhanced sensitivity for AMB (ATS). The modifications that result in enhanced AmB sensitivity of isolates are not associated with reduced virulence in vivo; instead, the ATS-infected mice died even faster than the ATR-infected animals. Since A. terreus enters the blood stream in most patients and frequently induces thrombosis, we studied a putative correlation between virulence of the two A. terreus isolates and their effect on thrombocytes. Those mice infected with the more virulent ATS isolate had lower thrombocyte numbers and more phosphatidylserine exposure on platelets than ATR-infected mice. In vitro experiments confirmed that ATS and ATR differ in their effect on thrombocytes. Conidia, aleurioconidia and hyphae of ATS were more potent than ATR to trigger thrombocyte stimulation, and thrombocytes adhered better to ATS than to ATR fungal structures. Furthermore, ATS secreted more soluble factors that triggered platelet stimulation than ATR. Thus, it might be suggested that the capacity of a fungal isolate to modulate thrombocyte parameters contributes to its virulence in vivo. 相似文献
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Theresa Linnemann Enno J. Kramer Falk Schwendicke Thomas Gerhard Wolf Hendrik Meyer-Lueckel Richard Johannes Wierichs 《Journal of endodontics》2021,47(4):577-584
IntroductionThe aims of this multicenter, practice-based cohort study were to evaluate the success and survival of endodontically treated teeth with post restorations (ETT+Ps) and to analyze factors associated with the longevity of ETT+Ps.MethodsEight general dental practitioners each placed up to 27 ETT+Ps without any restriction to post materials or dimensions. Only incisors, canines, and premolars were included. At the last follow-up visit, ETT+Ps were considered as successful if the post and the initially placed definitive restoration were sufficient, whereas ETT+Ps were considered as survived if the post was still in function. Multilevel Cox proportional hazards models were used to evaluate the association between a range of predictors and time until no success and no survival.ResultsOverall, 195 endodontic posts in 195 patients were followed up for a mean (95% confidence interval) of 91 (81–101) months; the longest follow-up was 15 years. Of these, 122 ETT+Ps were considered successful (estimated success time = 110 [101–120] months), and 152 ETT+Ps survived [estimated survival time = 133 [124–141] months). Regarding the categories of success and survival, the annual failure rates were 6.0% and 3.3%, respectively. Recementation of old (telescopic) crowns after placing new posts was the only significant predictor for decreased time until failure for both success and survival analyses. By excluding recemented restorations, annual failure rates decreased to 3.5% and 2.1%, respectively.ConclusionsFor EET+Ps placed in a private practice setting, high success and survival rates were observed. If old (telescopic) crowns were recemented after new posts were placed, the high risk of subsequent failure should be considered and communicated with patients. 相似文献
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