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91.
Simpson MA Irving MD Asilmaz E Gray MJ Dafou D Elmslie FV Mansour S Holder SE Brain CE Burton BK Kim KH Pauli RM Aftimos S Stewart H Kim CA Holder-Espinasse M Robertson SP Drake WM Trembath RC 《Nature genetics》2011,43(4):303-305
We used an exome-sequencing strategy and identified an allelic series of NOTCH2 mutations in Hajdu-Cheney syndrome, an autosomal dominant multisystem disorder characterized by severe and progressive bone loss. The Hajdu-Cheney syndrome mutations are predicted to lead to the premature truncation of NOTCH2 with either disruption or loss of the C-terminal proline-glutamate-serine-threonine-rich proteolytic recognition sequence, the absence of which has previously been shown to increase Notch signaling. 相似文献
92.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Black knot disease of chokecherries, induced by Dibotryon morbosum (Schw.) Th. & Syd., is widely distributed in Utah. The incidence of black knot was measured by determining the ratio of total black knot gall length to total stem length of plants and then expressing that value as a percentage of diseased stems in the sample plot. The environmental site factors measured were elevation, exposure, slope, soil pH, soil depth, distance to surface water, plant moisture stress, and associated vegetation. Numerical values were determined for each of these variables at each of 18 randomly located plots. Correlation coefficients for plant moisture stress and soil temperature were –.439 (p = .065) and –.440 (p = .055). Multiple regression analyses using plant moisture stress and soil temperature gave a regression coefficient of –.641 (p = .05). As plant moisture stress and soil temperature decreased, incidence of black knot increased. 相似文献
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96.
Stewart B. Peck 《西北部美国博物学家》2011,41(2)
Seven large caves in the Uinta Mountains, Utah, were surveyed for their invertebrate faunas. Thirty-eight species were found, and 30 of these are typical cave inhabitants. Diptera are the predominant group. Cave-restricted species are an amphipod, two diplurans, and possibly a Rhagidia mite. The caves were probablv uninhabitable in the past glacial because of severe periglacial environmental conditions, and the faunas have moved into the present cave sites since deglaciation of the Uintas. 相似文献
97.
The paper describes a project carried out within a major chemicals corporation to improve the performance of the individual
businesses. This was to be done by clarifying some of the organisational uncertainties in its structure and improving the
way that specialists form coalitions to address market challenges together. The approach used was based on “systems thinking”,
which is an intellectual framework of knowledge that attempts to view organisations as wholes and which studies the processes
of change in any part in the context of the whole organisation. Some of the important concepts of systems thinking are explored
as they might be applied within a business organisation. Specifically the tool used was the Viable System Model of Stafford
Beer, which the authors interpreted and developed into a set of statements (“a Standard”) which describe best practice in
such organisations. Managers have used this to explore possible gaps in their organisations and, with this understanding,
find ways to improve performance. 相似文献
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Bendall SC Stewart MH Menendez P George D Vijayaragavan K Werbowetski-Ogilvie T Ramos-Mejia V Rouleau A Yang J Bossé M Lajoie G Bhatia M 《Nature》2007,448(7157):1015-1021
Distinctive properties of stem cells are not autonomously achieved, and recent evidence points to a level of external control from the microenvironment. Here, we demonstrate that self-renewal and pluripotent properties of human embryonic stem (ES) cells depend on a dynamic interplay between human ES cells and autologously derived human ES cell fibroblast-like cells (hdFs). Human ES cells and hdFs are uniquely defined by insulin-like growth factor (IGF)- and fibroblast growth factor (FGF)-dependence. IGF 1 receptor (IGF1R) expression was exclusive to the human ES cells, whereas FGF receptor 1 (FGFR1) expression was restricted to surrounding hdFs. Blocking the IGF-II/IGF1R pathway reduced survival and clonogenicity of human ES cells, whereas inhibition of the FGF pathway indirectly caused differentiation. IGF-II is expressed by hdFs in response to FGF, and alone was sufficient in maintaining human ES cell cultures. Our study demonstrates a direct role of the IGF-II/IGF1R axis on human ES cell physiology and establishes that hdFs produced by human ES cells themselves define the stem cell niche of pluripotent human stem cells. 相似文献
100.