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排序方式: 共有229条查询结果,搜索用时 15 毫秒
141.
Anne Helene S. Tandberg Hans Tore Rapp Christoffer Schander Wim Vader 《Journal of Natural History》2013,47(25-28):1875-1889
The recently erected amphipod genus Exitomelita (Tandberg et al., 2012) has so far been found only associated with the deep-water hydrothermal vent field “Loki's Castle” in the Norwegian-Greenland Sea. There it was found on the black smoker chimney walls as well as within fields of the tubeworm Sclerolinum contortum in sulphide- and methane-rich sediments surrounding the vent field. A new species has now been found in a large wood fall of pine at 2800 m depth close to this vent field. This group of amphipods is apparently confined to reduced habitats, and our data support the theory that the vent fauna in this area is closely related to fauna found on cold seeps and wood falls in the northernmost Atlantic and Arctic Oceans. Here we present morphological and molecular data and a short discussion of the habitat of the new species, in addition to a comparison with the previously described species of Exitomelita.http://www.zoobank.org/urn:lsid:zoobank.org:pub:2B0B3CC2-AB6A-4006-83BB-182280CB22B8 相似文献
142.
Lgr5 marks cycling, yet long-lived, hair follicle stem cells 总被引:1,自引:0,他引:1
Jaks V Barker N Kasper M van Es JH Snippert HJ Clevers H Toftgård R 《Nature genetics》2008,40(11):1291-1299
In mouse hair follicles, a group of quiescent cells in the bulge is believed to have stem cell activity. Lgr5, a marker of intestinal stem cells, is expressed in actively cycling cells in the bulge and secondary germ of telogen hair follicles and in the lower outer root sheath of anagen hair follicles. Here we show that Lgr5(+) cells comprise an actively proliferating and multipotent stem cell population able to give rise to new hair follicles and maintain all cell lineages of the hair follicle over long periods of time. Lgr5(+) progeny repopulate other stem cell compartments in the hair follicle, supporting the existence of a stem or progenitor cell hierarchy. By marking Lgr5(+) cells during trafficking through the lower outer root sheath, we show that these cells retain stem cell properties and contribute to hair follicle growth during the next anagen. Expression analysis suggests involvement of autocrine Hedgehog signaling in maintaining the Lgr5(+) stem cell population. 相似文献
143.
Kornak U Reynders E Dimopoulou A van Reeuwijk J Fischer B Rajab A Budde B Nürnberg P Foulquier F;ARCL Debré-type Study Group Lefeber D Urban Z Gruenewald S Annaert W Brunner HG van Bokhoven H Wevers R Morava E Matthijs G Van Maldergem L Mundlos S 《Nature genetics》2008,40(1):32-34
We identified loss-of-function mutations in ATP6V0A2, encoding the a2 subunit of the V-type H+ ATPase, in several families with autosomal recessive cutis laxa type II or wrinkly skin syndrome. The mutations result in abnormal glycosylation of serum proteins (CDG-II) and cause an impairment of Golgi trafficking in fibroblasts from affected individuals. These results indicate that the a2 subunit of the proton pump has an important role in Golgi function. 相似文献
144.
Xia B Dorsman JC Ameziane N de Vries Y Rooimans MA Sheng Q Pals G Errami A Gluckman E Llera J Wang W Livingston DM Joenje H de Winter JP 《Nature genetics》2007,39(2):159-161
The Fanconi anemia and BRCA networks are considered interconnected, as BRCA2 gene defects have been discovered in individuals with Fanconi anemia subtype D1. Here we show that a defect in the BRCA2-interacting protein PALB2 is associated with Fanconi anemia in an individual with a new subtype. PALB2-deficient cells showed hypersensitivity to cross-linking agents and lacked chromatin-bound BRCA2; these defects were corrected upon ectopic expression of PALB2 or by spontaneous reversion. 相似文献
145.
论述了一种以焊缝几何模型和焊接过程模型为基础的管道机器人自动焊接系统,通过对管道定位机构(工件定位器)和焊接机器人的运动协调控制,使得在整个焊接过程中,焊缝相对于重力始终保持于最佳方向,同时焊枪相对于焊缝也保持在最佳方位上。文章首先介绍了系统的总体概念,接着详细讨论了工件定位器和焊接机器人的运动控制算法,最后通过实验和仿真验证了系统的可行性。 相似文献
146.
147.
Ngo VN Young RM Schmitz R Jhavar S Xiao W Lim KH Kohlhammer H Xu W Yang Y Zhao H Shaffer AL Romesser P Wright G Powell J Rosenwald A Muller-Hermelink HK Ott G Gascoyne RD Connors JM Rimsza LM Campo E Jaffe ES Delabie J Smeland EB Fisher RI Braziel RM Tubbs RR Cook JR Weisenburger DD Chan WC Staudt LM 《Nature》2011,470(7332):115-119
The activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) remains the least curable form of this malignancy despite recent advances in therapy. Constitutive nuclear factor (NF)-κB and JAK kinase signalling promotes malignant cell survival in these lymphomas, but the genetic basis for this signalling is incompletely understood. Here we describe the dependence of ABC DLBCLs on MYD88, an adaptor protein that mediates toll and interleukin (IL)-1 receptor signalling, and the discovery of highly recurrent oncogenic mutations affecting MYD88 in ABC DLBCL tumours. RNA interference screening revealed that MYD88 and the associated kinases IRAK1 and IRAK4 are essential for ABC DLBCL survival. High-throughput RNA resequencing uncovered MYD88 mutations in ABC DLBCL lines. Notably, 29% of ABC DLBCL tumours harboured the same amino acid substitution, L265P, in the MYD88 Toll/IL-1 receptor (TIR) domain at an evolutionarily invariant residue in its hydrophobic core. This mutation was rare or absent in other DLBCL subtypes and Burkitt's lymphoma, but was observed in 9% of mucosa-associated lymphoid tissue lymphomas. At a lower frequency, additional mutations were observed in the MYD88 TIR domain, occurring in both the ABC and germinal centre B-cell-like (GCB) DLBCL subtypes. Survival of ABC DLBCL cells bearing the L265P mutation was sustained by the mutant but not the wild-type MYD88 isoform, demonstrating that L265P is a gain-of-function driver mutation. The L265P mutant promoted cell survival by spontaneously assembling a protein complex containing IRAK1 and IRAK4, leading to IRAK4 kinase activity, IRAK1 phosphorylation, NF-κB signalling, JAK kinase activation of STAT3, and secretion of IL-6, IL-10 and interferon-β. Hence, the MYD88 signalling pathway is integral to the pathogenesis of ABC DLBCL, supporting the development of inhibitors of IRAK4 kinase and other components of this pathway for the treatment of tumours bearing oncogenic MYD88 mutations. 相似文献
148.
Sylvia E. Le Dévédec Kuan Yan Hans de Bont Veerander Ghotra Hoa Truong Erik H. Danen Fons Verbeek Bob van de Water 《Cellular and molecular life sciences : CMLS》2010,67(19):3219-3240
Cell migration is essential in a number of processes, including wound healing, angiogenesis and cancer metastasis. Especially,
invasion of cancer cells in the surrounding tissue is a crucial step that requires increased cell motility. Cell migration
is a well-orchestrated process that involves the continuous formation and disassembly of matrix adhesions. Those structural
anchor points interact with the extra-cellular matrix and also participate in adhesion-dependent signalling. Although these
processes are essential for cancer metastasis, little is known about the molecular mechanisms that regulate adhesion dynamics
during tumour cell migration. In this review, we provide an overview of recent advanced imaging strategies together with quantitative
image analysis that can be implemented to understand the dynamics of matrix adhesions and its molecular components in relation
to tumour cell migration. This dynamic cell imaging together with multiparametric image analysis will help in understanding
the molecular mechanisms that define cancer cell migration. 相似文献
149.
Gemoll T Roblick UJ Szymczak S Braunschweig T Becker S Igl BW Bruch HP Ziegler A Hellman U Difilippantonio MJ Ried T Jörnvall H Auer G Habermann JK 《Cellular and molecular life sciences : CMLS》2011,68(19):3261-3274
DNA aneuploidy has been identified as a prognostic factor for epithelial malignancies. Further understanding of the translation of DNA aneuploidy into protein expression will help to define novel biomarkers to improve therapies and prognosis. DNA ploidy was assessed by image cytometry. Comparison of gel-electrophoresis-based protein expression patterns of three diploid and four aneuploid colorectal cancer cell lines detected 64 ploidy-associated proteins. Proteins were identified by mass spectrometry and subjected to Ingenuity Pathway Analysis resulting in two overlapping high-ranked networks maintaining Cellular Assembly and Organization, Cell Cycle, and Cellular Growth and Proliferation. CAPZA1, TXNL1, and HDAC2 were significantly validated by Western blotting in cell lines and the latter two showed expression differences also in clinical samples using a tissue microarray of normal mucosa (n?=?19), diploid (n?=?31), and aneuploid (n?=?47) carcinomas. The results suggest that distinct protein expression patterns, affecting TXNL1 and HDAC2, distinguish aneuploid with poor prognosis from diploid colorectal cancers. 相似文献
150.