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排序方式: 共有196条查询结果,搜索用时 15 毫秒
191.
G Popa L Gavrilit? M S Mihailovici E Turtureanu-Hanganu 《Morphologie et embryologie》1989,35(3):199-203
Four cases (3 M, 1 F) of Lennert's lymphoma were presented. The age (38-76 years), the clinical aspect and the morphopathological features were characteristic. Despite an intensive chemotherapy, 3 of the 4 patients died between 2 and 16 months (mean survival time 7 months). The controversies about the nosological delimitation and the cellular nature of Lennert's lymphoma are presented. Because of the poor prognosis, it should be considered as a high-grade malignant non-Hodgkin lymphoma. 相似文献
192.
Thomas Asbeck Adam Benneter Alexander Huber Damaris Margaritis Jörn Buse Flavius Popa Patrick Pyttel Marc Förschler Stefanie Gärtner Jürgen Bauhus 《Ecology and evolution》2023,13(1):e9732
We report on a structural complexity enhancement (SCE) experiment that was designed to test ecological restoration measures in the Black Forest National Park, Germany. The main goal was to understand as to whether the creation of standing and downed deadwood within previously managed, single-layered Norway spruce (Picea abies L.) forests accelerates the development of forest structure, richness, and diversity of a range of taxonomic groups. Here we introduce the experimental design and describe the development of stand structure including abundance and richness of tree-related microhabitats (TreMs) within 5 years after initiation of the experiment in October 2016. To enhance structural complexity in treatment plots, 10 trees per plot were toppled using a skidder winch, and another 10 trees were ring barked at a height of around 60 cm above ground level with a chainsaw. To monitor stand structure, we collected data on common forest attributes such as diameter at breast height (DBH), tree height, and TreMs of all trees in the six experimental and six control plots measuring 0.25 ha in size before the treatments were carried out in 2016 and again in 2020/21. We analyzed the abundance and richness of TreMs using generalized linear mixed models with DBH and treatment vs. control as predictors. The SCE treatment resulted in a significant increase in deadwood volumes (4.2 vs. 439.5 m3) as well as in TreM abundance and richness (increase of 0.74 TreMs per tree). This indicates that the SCE treatment was effective to increase biodiversity-relevant structures such as deadwood and TreMs, in previously managed Norway spruce-dominated stands. The ongoing monitoring of a range of taxonomic groups (birds, bats, small mammals, coleoptera, fungi, mosses, and vascular plants) in this experiment will demonstrate to what extent the enhancement in structural complexity will lead to an enrichment in species richness and diversity. 相似文献
193.
O. Le Bon D. Popa E. Streel C. Alexandre C. Lena P. Linkowski J. Adrien 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(10):1021-1032
Sleep can be organized in two quite different ways across homeothermic species: either in one block (monophasic), or in several
bouts across the 24 h (polyphasic). Yet, the main relationships between variables, as well as regulating mechanisms, are likely
to be similar. Correlations and theories on sleep regulation should thus be examined on both types of sleepers. In previous
studies on monophasic humans, we have shown preferential links between the number of ultradian cycles and the rapid eye movement
sleep (REMS) time, rather than with its counterpart non-rapid eye movement sleep (NREMS). Here, the sleep of 26 polyphasic
mice was examined, both to better describe the NREMS distribution, which is far more complex than in humans, and to replicate
the analyses performed on humans. As in humans, the strongest links with the number of cycles were with REMS. Links were not
significant with NREMS taken as a whole, although positive correlations were found with the NREMS immediately preceding REMS
episodes and inversely significant with the residue. This convergence between monophasic and polyphasic patterns supports
the central role played by REMS in sleep alternation. 相似文献
194.
195.
Marcin Piwczyski Paulina Trzeciak Madalina‐Oana Popa Maciej Pabijan Jos María Corral Krzysztof Spalik Andrzej Grzywacz 《植物分类学报:英文版》2021,59(1):58-72
The angiosperm Apiaceae tribe Scandiceae includes four major clades—subtribes Daucinae, Ferulinae, Torilidinae, and Scandicinae—that originated ca. 20 Mya. Although all four subtribes are highly supported in molecular analyses, and morphological data indicate a sister relationship between Daucinae and Torilidinae, their branching order has not been resolved using standard Sanger multilocus data. Therefore, in this study, we test the utility of genomic RAD seq data in resolving deep phylogenetic relationships (up to 20 Mya) in Apiaceae subfamily Apioideae, with special emphasis on tribe Scandiceae using 12 representative species. We used two bioinformatic pipelines, pyRAD and RADIS (based on STACKS), to assemble RAD seq data and we tested the influence of various combinations of parameters on the robustness of the inferred tree topologies. Although different data processing approaches produced alignments with various amounts of missing data, they converged to two well‐supported topologies, irrespective of the phylogenetic method applied. Highly supported trees showed Scandicinae as sister to all other clades and indicated that Daucinae and Torilidinae are sister groups, thus confirming the relationship inferred from morphology. We conclude that the RAD seq method can be successfully used to resolve deep relationships formed 20 Mya within Apiaceae. We provide recommendations for parameter settings in RADIS and pyRAD for the analysis of taxa that have accumulated considerable genomic divergence. 相似文献
196.