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排序方式: 共有142条查询结果,搜索用时 15 毫秒
91.
Li J Yang Y Peng Y Austin RJ van Eyndhoven WG Nguyen KC Gabriele T McCurrach ME Marks JR Hoey T Lowe SW Powers S 《Nature genetics》2002,30(2):133-134
We found that PPM1D, encoding a serine/threonine protein phosphatase, lies within an epicenter of the region at 17q23 that is amplified in breast cancer. We show that overexpression of this gene confers two oncogenic phenotypes on cells in culture: attenuation of apoptosis induced by serum starvation and transformation of primary cells in cooperation with RAS. 相似文献
92.
The transmembrane glycoprotein CD98 is a potential regulator of multiple functions, including integrin signaling and amino acid transport. Abnormal expression or function of CD98 and disruption of the interactions between CD98 and its binding partners result in defects in cell homeostasis and immune responses. Indeed, expression of CD98 has been correlated with diseases such as inflammation and tumor metastasis. Modulation of CD98 expression and/or function therefore represents a promising therapeutic strategy for the treatment and prevention of such pathologies. Herein, we review the role of CD98 with focus on its functional importance in homeostasis and immune responses, which could help to better understand the pathogenesis of CD98-associated diseases. 相似文献
93.
The fragmentation of academic disciplines forces individuals to specialise. In doing so, they become experts over their narrow area of research. However, ambitious scientific projects, such as the search for gravitational waves, require them to come together and collaborate across disciplinary borders. How should scientists with expertise in different disciplines treat each others’ expert claims? An intuitive answer is that the collaboration should defer to the opinions of experts. In this paper we show that under certain seemingly innocuous assumptions, this intuitive answer gives rise to an impossibility result when it comes to aggregating the beliefs of experts to deliver the beliefs of a collaboration as a whole. We then argue that when experts’ beliefs come into conflict, they should waive their expert status. 相似文献
94.
95.
Dermal equivalents (DE), collagen lattices, were produced in vitro and used as a model for studying the possible role of a pure population of fibroblasts in post-radiotherapeutic dermal fibrosis. Single doses of gamma irradiation induced a partial inhibition of the collagen lattice retraction and of protein synthesis. The collagen production was less inhibited than was synthesis of non-collagen protein, which resulted in an increase of the relative amount of collagen synthesized by irradiated fibroblasts. These data suggest that gamma irradiation might be able to select some fibroblast clones able to produce increasing amounts of collagen. This selection process could be involved in the development of tissue fibrosis after therapeutic radiation. 相似文献
96.
Van Laere AS Nguyen M Braunschweig M Nezer C Collette C Moreau L Archibald AL Haley CS Buys N Tally M Andersson G Georges M Andersson L 《Nature》2003,425(6960):832-836
Most traits and disorders have a multifactorial background indicating that they are controlled by environmental factors as well as an unknown number of quantitative trait loci (QTLs). The identification of mutations underlying QTLs is a challenge because each locus explains only a fraction of the phenotypic variation. A paternally expressed QTL affecting muscle growth, fat deposition and size of the heart in pigs maps to the IGF2 (insulin-like growth factor 2) region. Here we show that this QTL is caused by a nucleotide substitution in intron 3 of IGF2. The mutation occurs in an evolutionarily conserved CpG island that is hypomethylated in skeletal muscle. The mutation abrogates in vitro interaction with a nuclear factor, probably a repressor, and pigs inheriting the mutation from their sire have a threefold increase in IGF2 messenger RNA expression in postnatal muscle. Our study establishes a causal relationship between a single-base-pair substitution in a non-coding region and a QTL effect. The result supports the long-held view that regulatory mutations are important for controlling phenotypic variation. 相似文献
97.
Human cytomegalovirus (HCMV) is a widespread opportunistic herpesvirus that causes severe and fatal diseases in immune-compromised individuals, including organ transplant recipients and individuals with AIDS. It is also a leading cause of virus-associated birth defects and is associated with atherosclerosis and coronary restenosis. HCMV initiates infection and intracellular signalling by binding to its cognate cellular receptors and by activating several signalling pathways including those mediated by mitogen-activated protein kinase, phosphatidylinositol-3-OH kinase, interferons, and G proteins. But a cellular receptor responsible for viral entry and HCMV-induced signalling has yet to be identified. Here we show that HCMV infects cells by interacting with epidermal growth factor receptor (EGFR) and inducing signalling. Transfecting EGFR-negative cells with an EGFR complementary DNA renders non-susceptible cells susceptible to HCMV. Ligand displacement and crosslinking analyses show that HCMV interacts with EGFR through gB, its principal envelope glycoprotein. gB preferentially binds EGFR and EGFR-ErbB3 oligomeric molecules in Chinese hamster ovary cells transfected with erbB family cDNAs. Taken together, these data indicate that EGFR is a necessary component for HCMV-triggered signalling and viral entry. 相似文献
98.
Hillier LW Fulton RS Fulton LA Graves TA Pepin KH Wagner-McPherson C Layman D Maas J Jaeger S Walker R Wylie K Sekhon M Becker MC O'Laughlin MD Schaller ME Fewell GA Delehaunty KD Miner TL Nash WE Cordes M Du H Sun H Edwards J Bradshaw-Cordum H Ali J Andrews S Isak A Vanbrunt A Nguyen C Du F Lamar B Courtney L Kalicki J Ozersky P Bielicki L Scott K Holmes A Harkins R Harris A Strong CM Hou S Tomlinson C Dauphin-Kohlberg S Kozlowicz-Reilly A Leonard S Rohlfing T Rock SM Tin-Wollam AM Abbott A 《Nature》2003,424(6945):157-164
99.
Epithelial supporting cells can differentiate into outer hair cells and Deiters' cells in the cultured organ of Corti 总被引:2,自引:0,他引:2
Malgrange B Thiry M Van De Water TR Nguyen L Moonen G Lefebvre PP 《Cellular and molecular life sciences : CMLS》2002,59(10):1744-1757
The organ of Corti is a complex structure containing a single row of inner hair cells (IHCs) and three rows of outer hair
cells (OHCs), supported respectively by one row of inner phalangeal cells and three rows of Deiters' cells. When fetal rat
organ of Corti explants are cultured, supernumerary OHCs and supernumerary Deiters' cells are produced, without any additional
cell proliferation. Analysis of semi- and ultrathin sections revealed that supernumerary OHCs are produced at the distal edge
of the organ of Corti. Quantitative analysis of cell types present in the organ of Corti demonstrates that when the number
of OHCs increases: (i) the total number of cells remains constant; (ii) the number of Deiters' cells increases; (iii) the
number of tectal cells decreases and of Hensen's cells decreases. Using specific HC markers, i.e. jagged2 (Jag2) and Math1,
we showed that in addition to existing OHCs, supernumerary OHCs, tectal cells and Hensen's cells expressed these markers in
embryonic day 19 organ of Corti explants after 5 days in vitro. The results of this study suggest that Hensen's cells retain
the capacity to differentiate into either tectal cells, which differentiate into OHCs, or into undertectal cells which differentiate
into Deiters' cells.
Received 15 May 2002; received after revision 18 July 2002; accepted 7 August 2002
RID="*"
ID="*"Corresponding author. 相似文献
100.
The spectrum of infection with Aeromonas and Plesiomonas included gastroenteritis, bacteremia, biliary tract infection, perirectal infection, and disseminated disease. Most patients (86%) with bacteremia were neutropenic (less than 500 PMN/mm3). Colonization of stools and sputum also occurred. Therapy with aminoglycosides, beta-lactams, trimethoprim/sulfamethoxazole, and the newer quinolones was effective in patients with AIDS and cancer. 相似文献