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排序方式: 共有230条查询结果,搜索用时 31 毫秒
181.
Barbieri CE Baca SC Lawrence MS Demichelis F Blattner M Theurillat JP White TA Stojanov P Van Allen E Stransky N Nickerson E Chae SS Boysen G Auclair D Onofrio RC Park K Kitabayashi N MacDonald TY Sheikh K Vuong T Guiducci C Cibulskis K Sivachenko A Carter SL Saksena G Voet D Hussain WM Ramos AH Winckler W Redman MC Ardlie K Tewari AK Mosquera JM Rupp N Wild PJ Moch H Morrissey C Nelson PS Kantoff PW Gabriel SB Golub TR Meyerson M Lander ES Getz G Rubin MA Garraway LA 《Nature genetics》2012,44(6):685-689
182.
183.
Gordon M. Ritcey 《清华大学学报》2006,11(2):137-152
Introduction Solvent extraction as applied to refining operations, particularly uranium, commenced in the late 1940s. These plants were small by present plant sizes. Shortly after, and almost 50 years ago now, the first solvent extraction plant was installed to treat hydrometallurgi-cal solutions at the mine site for the recovery of ura-nium. The success in this first generation of uranium operations in the 1950s and 1960s eventually led to the application of solvent extraction to copper opera… 相似文献
184.
In 1979, the walnut spanworm defoliated a 1 ha bitterbrush seed orchard near Nephi, Utah. No seed was produced for two years thereafter due to feeding damage. Life stages were described and illustrated. The female is brachypterous and incapable of flight. First instar larvae readily drop on their silk threads and probably are dispersed by wind. The insect has one annual generation. Moths laid an average of 159 eggs per cluster in April; larvae began to appear in early May and matured by the first week of June. The pupal period extended from June until mid-April. The parasitic bombyliid, Villa faustina (Osten Sacken), was reared from pupae. In April 1980, shrubs contained an estimated average of 1044 eggs each. On 19 May, larvae averaged 1.9 per 7.5 cm of twig and were in the first and second instar. On 20 May the population was controlled by spraying with Sevimol-4. Other potential host plants, as determined from greenhouse tests, are rose, ceanothus, mountain mahogany, serviceberry, and willow. 相似文献
185.
Gordon McOuat 《Annals of science》2013,70(2):189-195
Einleitend wird die wissenschaftliche Polemik als ein wesentliches Element des modernen Wissenschaftsbetriebes charakterisiert und auf ökonomische Ursachen und Hintergründe verwiesen. Als Ursache für den Gegensatz zwischen Plücker und Steiner werden danach die von Crelle betriebenen Berufungen an das sogenannte Berliner ‘polytechnische’ Institut wahrscheinlich gemacht, das in Wirklichkeit als eine Art von pädagogischer Hochschule geplant war. Die Geschichte dieser nie verwirklichten Einrichtung wird soweit dargestellt, wie sie mit den in Aussicht genommenen Berufungen von Plücker und Steiner im Zusammenhang stand. Abschließend werden zwei Gutachten Crelles über Plücker im Wortlaut wiedergegeben, die er in seiner amtlichen Eigenschaft als Fachreferent für Mathematik im preußischen Kultusministerium verfaßte. 相似文献
186.
Megan Chircop Chandra S. Malladi Audrey T. Lian Scott L. Page Michael Zavortink Christopher P. Gordon Adam McCluskey Phillip J. Robinson 《Cellular and molecular life sciences : CMLS》2010,67(21):3725-3737
Successful completion of cytokinesis requires the spatio-temporal regulation of protein phosphorylation and the coordinated
activity of protein kinases and phosphatases. Many mitotic protein kinases are well characterized while mitotic phosphatases
are largely unknown. Here, we show that the Ca2+- and calmodulin-dependent phosphatase, calcineurin (CaN), is required for cytokinesis in mammalian cells, functioning specifically
at the abscission stage. CaN inhibitors induce multinucleation in HeLa cells and prolong the time cells spend connected via
an extended intracellular bridge. Upon Ca2+ influx during cytokinesis, CaN is activated, targeting a set of proteins for dephosphorylation, including dynamin II (dynII).
At the intracellular bridge, phospho-dynII and CaN are co-localized to dual flanking midbody rings (FMRs) that reside on either
side of the central midbody ring. CaN activity and disassembly of the FMRs coincide with abscission. Thus, CaN activity at
the midbody plays a key role in regulating the completion of cytokinesis in mammalian cells. 相似文献
187.
Christine C. Gordon 《西北部美国博物学家》2011,46(1)
Eighteen pine marten ( Martes americana ) stomachs and 29 intestinal tracts, collected between October 1983 and March 1984 from northern Colorado, were examined for food items. Voles ( Microtus spp.) occurred most frequently, followed by shrews ( Sorex spp.), insects, and vegetative matter. 相似文献
188.
戈登·麦克比恩 《科技导报(北京)》2019,37(2):13-15
如何利用科学素质,让人类更好地实现促进可持续发展这一目标,是一个值得思考的问题。可持续发展,即人类不仅有能力确保当前需求得到满足,而且不会影响到未来的需求。这样一种将过去与未来相连的概念,需要更深刻地理解这个问题,科学、技术和社会如何能够共同发挥作用,彼此互补,使三者在未来实现和谐发展、相互促进。同时也需要了解社会、经济、技术、科学和环境等问题之间的相互关系。把未来和现在进行关联是一项非常大的挑战,科学素质是其中一个很重要的问题,如何让人们了解科学素质与人类可持续发展的关系,怎样把未来和过去相联接,需要在决策中体现出来。 相似文献
189.
Gehrig SM van der Poel C Sayer TA Schertzer JD Henstridge DC Church JE Lamon S Russell AP Davies KE Febbraio MA Lynch GS 《Nature》2012,484(7394):394-398
Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder caused by mutations in the dystrophin gene that result in the absence of the membrane-stabilizing protein dystrophin. Dystrophin-deficient muscle fibres are fragile and susceptible to an influx of Ca(2+), which activates inflammatory and muscle degenerative pathways. At present there is no cure for DMD, and existing therapies are ineffective. Here we show that increasing the expression of intramuscular heat shock protein 72 (Hsp72) preserves muscle strength and ameliorates the dystrophic pathology in two mouse models of muscular dystrophy. Treatment with BGP-15 (a pharmacological inducer of Hsp72 currently in clinical trials for diabetes) improved muscle architecture, strength and contractile function in severely affected diaphragm muscles in mdx dystrophic mice. In dko mice, a phenocopy of DMD that results in severe spinal curvature (kyphosis), muscle weakness and premature death, BGP-15 decreased kyphosis, improved the dystrophic pathophysiology in limb and diaphragm muscles and extended lifespan. We found that the sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA, the main protein responsible for the removal of intracellular Ca(2+)) is dysfunctional in severely affected muscles of mdx and dko mice, and that Hsp72 interacts with SERCA to preserve its function under conditions of stress, ultimately contributing to the decreased muscle degeneration seen with Hsp72 upregulation. Treatment with BGP-15 similarly increased SERCA activity in dystrophic skeletal muscles. Our results provide evidence that increasing the expression of Hsp72 in muscle (through the administration of BGP-15) has significant therapeutic potential for DMD and related conditions, either as a self-contained therapy or as an adjuvant with other potential treatments, including gene, cell and pharmacological therapies. 相似文献
190.