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1.
A multigene phylogenetic study was carried out to test current, mostly morphology-based hypotheses on Sterrhinae phylogeny with additional material included from further geographical areas and morphologically different lineages. A maximum likelihood analysis (11 molecular markers and 7665 bp) was conducted on 76 species and 41 genera using iq-tree software. The resulting phylogenetic hypothesis is well resolved and branches have high support values. Results generally agree with earlier hypotheses at tribal levels and support the hypothesis that Sterrhinae comprises two major lineages. Based on the molecular phylogeny and extensive morphological examination, nine tribes are considered valid and the following taxonomic changes are introduced to recognize monophyletic groups: Mecoceratini Guenée, 1858 (= Ametridini Prout, 1910) is transferred from Desmobathrinae to Sterrhinae, and it is considered valid at tribal level new classification ; Haemaleini Sihvonen & Brehm is described as a new tribe and deemed sister to Scopulini + Lissoblemmini; Lissoblemmini Sihvonen & Staude is described as a new tribe and sister to Scopulini; Lythriini Herbulot, 1962 is now a junior synonym of Rhodometrini Agenjo, 1952 syn.n. ; and Rhodostrophiini Prout, 1935 is now a junior synonym of Cyllopodini Kirby, 1892 syn.n. In addition, 48 taxa are transferred from other geometrid subfamilies to Sterrhinae, or within Sterrhinae from one tribe to another, or they are classified into a tribe for the first time, or a new genus classification is proposed. The results demonstrate the limited explanatory power of earlier classifications, particularly at the tribal level. This is probably a result of earlier classifications being based on superficial characters and biased towards the European and North American fauna. The species richness and distribution of Sterrhinae and its constituent tribes are reviewed, showing that the globally distributed Sterrhinae are most diverse in the Neotropics (31% of global fauna). They are species-rich in the Palaearctic (22%), Afrotropics (19%) and Indo-Malay (16%) regions, whereas they are almost absent in Oceania (1%). In terms of the described fauna, the most species-rich tribes are Scopulini (928 species), Sterrhini (876 species) and Cosymbiini (553 species), all of which have a cosmopolitan distribution. Mecoceratiini and Haemaleini are almost entirely Neotropical. Timandrini and Lissoblemmini, by contrast, are absent in the Neotropics. We present a revised classification of the global Sterrhinae fauna, which includes about 3000 putatively valid species, classified into nine tribes and 97 genera. Four genera are of uncertain position within Sterrhinae. Our results highlight the compelling need to include more genera from a global perspective in molecular phylogenetic studies, in order to create a stable global classification for this subfamily. This published work has been registered on ZooBank, http://zoobank.org/urn:lsid:zoobank.org :pub:A66F5DDD-06D6-4908-893E-E8B124BB99B1.  相似文献   
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The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimualting effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin–HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 μM), which was primarily cytotoxic and a physiological range (below 10 μM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well.  相似文献   
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Ohne ZusammenfassungAnregung zu dieser Arbeit und Beratung durch Prof. L.Burkhardt.  相似文献   
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Summary The ultrastructure of glycerol extracted thrombocyte models was studied before and after incubation with ATP and under the influence of Salyrgan as inhibitor of contraction. The contractile system of the thrombocytes—thrombosthenin—consists of a spatial network of 50 Å wide thrombosthenin A and 100–120 Å wide thrombosthenin M filaments. At rest, the contractile system is arranged in a marginal zone. The ATP-induced contraction led to a concentric condensation of the network which resulted in a central cluster of cell organelles and at a later stage, disruption of the plasma membrane and release of the thrombocyte granules. All these changes which also occur during the formation of the hemostatic plug in vivo are therefore attributed to the reaction of the contractile protein.  相似文献   
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