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51.
52.
T W Teasdale  D R Owen 《Nature》1984,309(5969):620-622
Although it is well established that family members resemble each other in intelligence , the extent to which this results from either shared genes or a shared environment remains controversial, perhaps especially since the relevant evidence presented by Burt has been shown probably to have been fabricated. The influence of heredity and familial environment may be distinguished by studying adoptees. Here we present correlations in intelligence and educational level between genetically related pairs of adult adoptees who have been reared separately, and, conversely, between genetically unrelated pairs of adult adoptees who have been reared together. We are unaware of any previous study of adults which has reported on both of these types of relationship. The results for intelligence conform closely to what would be predicted by a simple polygenic model of genetic transmission whereas those for educational attainment imply both genetic and familial environmental components.  相似文献   
53.
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An intense stratospheric jet on Jupiter   总被引:1,自引:0,他引:1  
The Earth's equatorial stratosphere shows oscillations in which the east-west winds reverse direction and the temperatures change cyclically with a period of about two years. This phenomenon, called the quasi-biennial oscillation, also affects the dynamics of the mid- and high-latitude stratosphere and weather in the lower atmosphere. Ground-based observations have suggested that similar temperature oscillations (with a 4-5-yr cycle) occur on Jupiter, but these data suffer from poor vertical resolution and Jupiter's stratospheric wind velocities have not yet been determined. Here we report maps of temperatures and winds with high spatial resolution, obtained from spacecraft measurements of infrared spectra of Jupiter's stratosphere. We find an intense, high-altitude equatorial jet with a speed of approximately 140 m s(-1), whose spatial structure resembles that of a quasi-quadrennial oscillation. Wave activity in the stratosphere also appears analogous to that occurring on Earth. A strong interaction between Jupiter and its plasma environment produces hot spots in its upper atmosphere and stratosphere near its poles, and the temperature maps define the penetration of the hot spots into the stratosphere.  相似文献   
55.
Gingerich O 《Nature》2004,430(6998):407
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56.
Tylianakis JM  Tscharntke T  Lewis OT 《Nature》2007,445(7124):202-205
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57.
Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an autosomal-dominant central nervous system white-matter disease with variable clinical presentations, including personality and behavioral changes, dementia, depression, parkinsonism, seizures and other phenotypes. We combined genome-wide linkage analysis with exome sequencing and identified 14 different mutations affecting the tyrosine kinase domain of the colony stimulating factor 1 receptor (encoded by CSF1R) in 14 families with HDLS. In one kindred, we confirmed the de novo occurrence of the mutation. Follow-up sequencing identified an additional CSF1R mutation in an individual diagnosed with corticobasal syndrome. In vitro, CSF-1 stimulation resulted in rapid autophosphorylation of selected tyrosine residues in the kinase domain of wild-type but not mutant CSF1R, suggesting that HDLS may result from partial loss of CSF1R function. As CSF1R is a crucial mediator of microglial proliferation and differentiation in the brain, our findings suggest an important role for microglial dysfunction in HDLS pathogenesis.  相似文献   
58.
Every effort is made to ensure everyone is counted in a census. However, no census is perfect and some people are missed. This underenumeration does not usually occur uniformly across all geographical areas or across other sub-groups of the population such as age and sex groups. Coverage levels in censuses across the world are declining leading to an increasing need to firstly slow the decline through improved enumeration, and secondly in improved methods and data for measuring coverage. In order to achieve the mission critical aims of the 2011 Census, a coverage assessment and adjustment strategy is required. This article outlines the proposed strategy for the 2011 UK Census. The strategy is to significantly improve upon the 2001 One Number Census, and use it as a platform to develop an improved coverage assessment and adjustment methodology. The article also outlines the key areas of innovation for the 2011 strategy and the options that will be considered in order to develop the final strategy. Stakeholder management is also an important part of the strategy to ensure that key users both buy into and understand the methodology. ONS will look to build on the consultation carried out prior to the 2001 Census and widen the user base with which it engages on this important topic.  相似文献   
59.
Naturally occurring variation in gene copy number is increasingly recognized as a heritable source of susceptibility to genetically complex diseases. Here we report strong association between FCGR3B copy number and risk of systemic lupus erythematosus (P = 2.7 x 10(-8)), microscopic polyangiitis (P = 2.9 x 10(-4)) and Wegener's granulomatosis in two independent cohorts from the UK (P = 3 x 10(-3)) and France (P = 1.1 x 10(-4)). We did not observe this association in the organ-specific Graves' disease or Addison's disease. Our findings suggest that low FCGR3B copy number, and in particular complete FCGR3B deficiency, has a key role in the development of systemic autoimmunity.  相似文献   
60.
Imidazole pyruvate was found to be a very potent natural chelating agent in reversing the inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+. This metabolite may play a physiological role in gluconeogenesis.  相似文献   
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