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151.
W S Glaunsinger T R White R B Von Dreele D A Gordon R F Marzke A L Bowman J L Yarnell 《Nature》1978,271(5644):414-417
The alkaline earth hexammines have novel structures and molecular motions. The ammonia molecules in these compounds adopt an entirely different geometry from that of normal ammonia. There are two motional transitions as the temperature is increased. The first transition is due to ammonia rotation, and the second results from ammonia diffusion. 相似文献
152.
该文通过34只罗猴头颈实验研究,从中决定罗猴的颅脑损伤容限.当颅脑受到冲击时,颅壳发生局部变形瞬间,大脑亦发生变形,致使颅内压升高.利用这些结果来确定它的损伤机制,以模拟宇航员在冲击载荷下的创伤分析模型,将有助于进行临床创伤治疗和宇航弹射时的防护. 相似文献
153.
Microbial ecology: human gut microbes associated with obesity 总被引:6,自引:0,他引:6
Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people, and that this proportion increases with weight loss on two types of low-calorie diet. Our findings indicate that obesity has a microbial component, which might have potential therapeutic implications. 相似文献
154.
Henao-Mejia J Elinav E Jin C Hao L Mehal WZ Strowig T Thaiss CA Kau AL Eisenbarth SC Jurczak MJ Camporez JP Shulman GI Gordon JI Hoffman HM Flavell RA 《Nature》2012,482(7384):179-185
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and the leading cause of chronic liver disease in the Western world. Twenty per cent of NAFLD individuals develop chronic hepatic inflammation (non-alcoholic steatohepatitis, NASH) associated with cirrhosis, portal hypertension and hepatocellular carcinoma, yet the causes of progression from NAFLD to NASH remain obscure. Here, we show that the NLRP6 and NLRP3 inflammasomes and the effector protein IL-18 negatively regulate NAFLD/NASH progression, as well as multiple aspects of metabolic syndrome via modulation of the gut microbiota. Different mouse models reveal that inflammasome-deficiency-associated changes in the configuration of the gut microbiota are associated with exacerbated hepatic steatosis and inflammation through influx of TLR4 and TLR9 agonists into the portal circulation, leading to enhanced hepatic tumour-necrosis factor (TNF)-α expression that drives NASH progression. Furthermore, co-housing of inflammasome-deficient mice with wild-type mice results in exacerbation of hepatic steatosis and obesity. Thus, altered interactions between the gut microbiota and the host, produced by defective NLRP3 and NLRP6 inflammasome sensing, may govern the rate of progression of multiple metabolic syndrome-associated abnormalities, highlighting the central role of the microbiota in the pathogenesis of heretofore seemingly unrelated systemic auto-inflammatory and metabolic disorders. 相似文献
155.
156.
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
157.
Gordon Rowland 《Systemic Practice and Action Research》2004,17(4):285-296
Sustainability has been introduced at Ithaca College as a potential guiding theme for a wide range of development efforts. How these efforts will shape the institution's future is unclear, particularly when one places them in the context of recent changes in the College's approach to governance and planning. Countering rather primitive applications of systems thinking in the popular literature on sustainability, a case is made that sustainability principles can be reframed within Banathy's [Banathy, B. H. (1989). Syst. Res.
6(4), 289–296.] notion of an evolutionary guidance system, and this could lead to the next evolutionary stage of the institution. 相似文献
158.
Churchill GA Airey DC Allayee H Angel JM Attie AD Beatty J Beavis WD Belknap JK Bennett B Berrettini W Bleich A Bogue M Broman KW Buck KJ Buckler E Burmeister M Chesler EJ Cheverud JM Clapcote S Cook MN Cox RD Crabbe JC Crusio WE Darvasi A Deschepper CF Doerge RW Farber CR Forejt J Gaile D Garlow SJ Geiger H Gershenfeld H Gordon T Gu J Gu W de Haan G Hayes NL Heller C Himmelbauer H Hitzemann R Hunter K Hsu HC Iraqi FA Ivandic B Jacob HJ Jansen RC Jepsen KJ Johnson DK Johnson TE Kempermann G 《Nature genetics》2004,36(11):1133-1137
The goal of the Complex Trait Consortium is to promote the development of resources that can be used to understand, treat and ultimately prevent pervasive human diseases. Existing and proposed mouse resources that are optimized to study the actions of isolated genetic loci on a fixed background are less effective for studying intact polygenic networks and interactions among genes, environments, pathogens and other factors. The Collaborative Cross will provide a common reference panel specifically designed for the integrative analysis of complex systems and will change the way we approach human health and disease. 相似文献
159.
Matthews JM Kuschnig R Guenther DB Walker GA Moffat AF Rucinski SM Sasselov D Weiss WW Kusching R 《Nature》2004,430(6995):51-53
Pressure-driven (p-mode) oscillations at the surface of the Sun, resulting from sound waves travelling through the solar interior, are a powerful probe of solar structure, just as seismology can reveal details about the interior of the Earth. Astronomers have hoped to exploit p-mode asteroseismology in Sun-like stars to test detailed models of stellar structure and evolution, but the observations are extremely difficult. The bright star Procyon has been considered one of the best candidates for asteroseismology, on the basis of models and previous reports of p-modes detected in ground-based spectroscopy. Here we present a search for p-modes in 32 days of nearly continuous photometric satellite-based observations of Procyon. If there are p-modes in Procyon, they must have lifetimes less than 2-3 days and/or peak amplitudes <15 parts per million, which defy expectations from the Sun's oscillations and previous theoretical predictions. Target selection for future planned asteroseismology space missions may need to be reconsidered, as will the theory of stellar oscillations. 相似文献
160.