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991.
Fossil wood collections at the Natural History Museum, London, were searched for the type material of two important species, described as early as 1831 by Witham, on the basis of material at least partly furnished by Nicol and collected in the Liassic of Whitby (Yorkshire, UK). The names given to these two species by Witham are the basionyms for more than ten other species names, while these species names also provide syntypes for several generic names. Despite this, the original material has been only rarely and partly revised, leading to much confusion.We managed to locate some of the original material. Several topotypes were also studied. On the basis of this review we propose here a neotypification for Peuce huttoniana Witham, a lectotypification for Cupressinoxylon barberi Seward and a lectotypification for Tiloxylon Hartig. We evidence several taxonomical and nomenclatural synonymies, assign Peuce lindleyana Witham to Protocedroxylon and P. huttoniana to Xenoxylon Gothan, and introduce the new combination Xenoxylon huttonianum (Witham) nov. comb. as the correct name for Xenoxylon ellipticum Gottwald & Holleis ex Schultze-Motel.A topotype of Araucariopitys americana Hollick & Jeffrey was also reviewed, which, together with previous results, leads us to suggest that Araucariopitys Hollick & Jeffrey, Protocedroxylon Gothan and Planoxylon Stopes should not be considered as taxonomical synonyms. This point is crucial to the interpretation of the fossil record of Early Abietinae. 相似文献
992.
993.
Zornitza Andreeva Deborah Barton William J. Armour Min Y. Li Li-Fen Liao Heather L. McKellar Kylie A. Pethybridge Jan Marc 《Planta》2010,232(5):1263-1279
The phospholipase protein superfamily plays an important role in hormonal signalling and cellular responses to environmental
stimuli. There is also growing evidence for interactions between phospholipases and the cytoskeleton. In this report we used
a pharmacological approach to investigate whether inhibiting a member of the phospholipase superfamily, phospholipase C (PLC),
affects microtubules and actin microfilaments as well as root growth and morphology of Arabidopsis thaliana seedlings. Inhibiting PLC activity using the aminosteroid U73122 significantly inhibited root elongation and disrupted root
morphology in a concentration-dependent manner, with the response being saturated at 5 μM, whereas the inactive analogue U73343
was ineffective. The primary root appeared to lose growth directionality accompanied by root waving and formation of curls.
Immunolabelling of roots exposed to increasingly higher U73122 concentrations revealed that the normal transverse arrays of
cortical microtubules in the elongation zone became progressively more disorganized or depolymerized, with the disorganization
appearing within 1 h of incubation. Likewise, actin microfilament arrays also were disrupted. Inhibiting PLC using an alternative
inhibitor, neomycin, caused similar disruptions to both cytoskeletal organization and root morphology. In seedlings gravistimulated
by rotating the culture plates by 90°, both U73122 and neomycin disrupted the normal gravitropic growth of roots and etiolated
hypocotyls. The effects of PLC inhibitors are therefore consistent with the notion that, as with phospholipases A and D, PLC
likewise interacts with the cytoskeleton, alters growth morphology, and is involved in gravitropism. 相似文献
994.
995.
Anna B Roehl Marc Hein Philipp D Loetscher Jan Rossaint Joachim Weis Rolf Rossaint Mark Coburn 《BMC neurology》2010,10(1):97
Background
We investigated the neuroprotective properties of levosimendan, a novel inodilator, in an in vitro model of traumatic brain injury. 相似文献996.
Fiona E McCann Andrew C Palfreeman Melanie Andrews Dany P Perocheau Julia J Inglis Peter Schafer Marc Feldmann Richard O Williams Fionula M Brennan 《Arthritis research & therapy》2010,12(3):R107
Introduction
Type 4 phosphodiesterases (PDE4) play an important role in immune cells through the hydrolysis of the second messenger, cAMP. Inhibition of PDE4 has previously been shown to suppress immune and inflammatory responses, demonstrating PDE4 to be a valid therapeutic target for immune-mediated pathologies. We assessed the anti-inflammatory effects of a novel PDE4 inhibitor, apremilast, in human synovial cells from rheumatoid arthritis (RA) patients, as well as two murine models of arthritis. 相似文献997.
Van Regenmortel MH 《Expert review of proteomics》2010,7(5):639-642
This meeting report describes some of the highlights of the First Biennial Aegean International Conference on Molecular Recognition that took place in Hersonissos, Crete, Greece, between 6 and 11 June 2010. The conference comprised four sessions devoted to: dynamic and combinatorial molecular recognition; B-cell epitope prediction, synthesis and vaccines; nanotechnology approaches to molecular recognition; and host-pathogen interactions. A total of 35 oral communications and 15 posters were presented. The second Aegean International Conference on Molecular Recognition is scheduled to take place in the spring of 2012. 相似文献
998.
Primary cilia are cell surface organelles that act as sensory antennae for various input signals. In a recent issue of Nature Cell Biology, Boehlke et?al. (2010) demonstrate that bending of cilia regulates cell size through a signaling pathway involving the LKB1 and mTOR kinases. 相似文献
999.