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排序方式: 共有70条查询结果,搜索用时 15 毫秒
1.
Extensive and coordinated transcription of noncoding RNAs within cell-cycle promoters 总被引:5,自引:0,他引:5
2.
Hugo Fernandes-Silva Patrícia Vaz-Cunha Violina Baranauskaite Barbosa Carla Silva-Gonçalves Jorge Correia-Pinto Rute Silva Moura 《Cellular and molecular life sciences : CMLS》2017,74(24):4599-4619
Retinoic acid (RA) is of major importance during vertebrate embryonic development and its levels need to be strictly regulated otherwise congenital malformations will develop. Through the action of specific nuclear receptors, named RAR/RXR, RA regulates the expression of genes that eventually influence proliferation and tissue patterning. RA has been described as crucial for different stages of mammalian lung morphogenesis, and as part of a complex molecular network that contributes to precise organogenesis; nonetheless, nothing is known about its role in avian lung development. The current report characterizes, for the first time, the expression pattern of RA signaling members (stra6, raldh2, raldh3, cyp26a1, rarα, and rarβ) and potential RA downstream targets (sox2, sox9, meis1, meis2, tgfβ2, and id2) by in situ hybridization. In the attempt of unveiling the role of RA in chick lung branching, in vitro lung explants were performed. Supplementation studies revealed that RA stimulates lung branching in a dose-dependent manner. Moreover, the expression levels of cyp26a1, sox2, sox9, rarβ, meis2, hoxb5, tgfβ2, id2, fgf10, fgfr2, and shh were evaluated after RA treatment to disclose a putative molecular network underlying RA effect. In situ hybridization analysis showed that RA is able to alter cyp26a1, sox9, tgfβ2, and id2 spatial distribution; to increase rarβ, meis2, and hoxb5 expression levels; and has a very modest effect on sox2, fgf10, fgfr2, and shh expression levels. Overall, these findings support a role for RA in the proximal–distal patterning and branching morphogenesis of the avian lung and reveal intricate molecular interactions that ultimately orchestrate branching morphogenesis. 相似文献
3.
Horlings HM Bergamaschi A Nordgard SH Kim YH Han W Noh DY Salari K Joosse SA Reyal F Lingjaerde OC Kristensen VN Børresen-Dale AL Pollack J van de Vijver MJ 《Nature genetics》2008,40(7):809; author reply 810-809; author reply 812
4.
We investigated, through an action research approach, social issues that impact on mobile technology adoption and diffusion
in a professional construction management team of a small-to-medium sized South African construction company. The outcome
of the study resulted in a framework of thinking that integrates social factors at individual and organisational levels that
impacted on the adoption of mobile technologies in the organisation. At the methodological level the study is part of a limited
collection of papers that used AR in the study of technology adoption and diffusion and it presents an example of the capability
of AR as a method to allow for the integration of the social contexts of users into adoption frameworks. 相似文献
5.
The thymus positively selects thymocytes that bear T-cell receptors which recognize antigen presented by self major histocompatibility complex (MHC) proteins. Positive selection is usually driven by MHC products on radiation-resistant cortical epithelial cells. It is unknown whether positive selection is mediated by all thymic epithelial cells or by some specialized subsets. Here we introduce an H-2b-expressing thymic epithelial cell line into the thymuses of lethally irradiated H-2k animals reconstituted with H-2b/k F1 BM or fetal liver cells. I-Ab-restricted T cells are found in these animals, demonstrating that selection occurs on the introduced epithelial cells. 相似文献
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Drosophila Crumbs (Crb) is required for apical-basal polarity and is an apical determinant in embryonic epithelia. Here, we describe properties of Crb that control the position and integrity of the photoreceptor adherens junction and photosensitive organ, or rhabdomere. In contrast to normal photoreceptor adherens junctions and rhabdomeres, which span the depth of the retina, adherens junctions and rhabdomeres of Crb-deficient photoreceptors initially accumulate at the top of the retina and fail to maintain their integrity as they stretch to the retinal floor. We show that Crb controls localization of the adherens junction through its intracellular domain containing a putative binding site for a protein 4.1 superfamily protein (FERM). Although loss of Crb or overexpression of the FERM binding domain causes mislocalization of adherens junctions, they do not result in a significant loss of photoreceptor polarity. Mutations in CRB1, a human homologue of crb, are associated with photoreceptor degeneration in retinitis pigmentosa 12 (RP12) and Leber congenital amaurosis (LCA). The intracellular domain of CRB1 behaves similarly to its Drosophila counterpart when overexpressed in the fly eye. Our studies may provide clues for mechanisms of photoreceptor degeneration in RP12 and LCA. 相似文献
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9.
Zusammenfassung Die instabile Katalase-Variante, welche in den Erythrocyten des Akatalasie-Falles A.B. vorkommt, lässt sich in vitro durch Zusatz von Anti-Katalase IgG-Fraktion oder von Fab-Fragmenten ohne Aktivitätseinbusse stabilisieren. Es wird angenommen, dass dies auf eine Fixierung der aktiven Konformation des Enzyms zurückzuführen ist. 相似文献
10.
Zusammenfassung Beim Akatalasie-Fall A.B. ist die in den Leukozyten vorhandene Katalase-Restaktivität wesentlich höher (13%) als diejenige in den Erythrozyten (etwa 1% der Norm), wie dies beim Vorliegen einer instabilen Enzymvariante zu erwarten ist. Die Enzyme beider Zelltypen sind antigen-identisch und zeigen denselben Grad von Thermolabilität. 相似文献