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Identifying genetic variants influencing human brain structures may reveal new biological mechanisms underlying cognition and neuropsychiatric illness. The volume of the hippocampus is a biomarker of incipient Alzheimer's disease and is reduced in schizophrenia, major depression and mesial temporal lobe epilepsy. Whereas many brain imaging phenotypes are highly heritable, identifying and replicating genetic influences has been difficult, as small effects and the high costs of magnetic resonance imaging (MRI) have led to underpowered studies. Here we report genome-wide association meta-analyses and replication for mean bilateral hippocampal, total brain and intracranial volumes from a large multinational consortium. The intergenic variant rs7294919 was associated with hippocampal volume (12q24.22; N = 21,151; P = 6.70 × 10(-16)) and the expression levels of the positional candidate gene TESC in brain tissue. Additionally, rs10784502, located within HMGA2, was associated with intracranial volume (12q14.3; N = 15,782; P = 1.12 × 10(-12)). We also identified a suggestive association with total brain volume at rs10494373 within DDR2 (1q23.3; N = 6,500; P = 5.81 × 10(-7)).  相似文献   
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Karl Popper and Michael Polanyi grew up in central Europe and, having escaped from Nazism, went on to pursue academic careers in Britain where they wrote prolifically on science and politics. Popper and Polanyi corresponded with each other, and met for discussions in the late 1940s and early 50s, but they seldom referred to each other in their publications. This article examines their correspondence so as to produce a picture of their intellectual relations. The most important of the letters was one that Popper wrote in 1952, which we reproduce in its entirety, indicating his dissatisfaction with ideas that Polanyi had expressed in a paper of that year, ‘The Stability of Beliefs’. In this paper, Polanyi used the example of the framework of Zande witchcraft to shed analogical light on science and other systems of belief, arguing that ‘frameworks of belief’ equip their adherents with intellectual powers whose use reinforces commitment to the framework, inoculating adherents against criticism. Polanyi’s 1952 paper and his 1951 and 1952 Gifford Lectures (to which that paper is intimately tied) are the first articulation of Polanyi’s sharp rejection of the modern critical philosophical tradition that by implication included Popper’s philosophical ideas. The 1952 paper is also part of Polanyi’s constructive philosophical effort to set forth a fiduciary philosophy emphasizing commitment. Popper regarded Polanyi’s position as implying cognitive relativism and irrationalism, and from the time of Polanyi’s 1952 paper their personal relationship became strained. Discord between them became publicly manifest when Polanyi subtitled his book Personal Knowledge (1958), Towards a post-critical philosophy, and Popper lambasted the idea of a ‘post-critical’ philosophy in his Preface in The Logic of Scientific Discovery (1959).  相似文献   
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海洋微生物及其代谢产物的研究在国际上是一个极受重视的新兴领域,发展很快,取得了丰硕成果.近年来,作者开展对南海海洋细菌和真菌活性物质的研究,从中分离出一些结构新颖的,有很好生理活性的化合物.386菌是从南海获得的一种海洋真菌,其代谢产物很丰富,以分离出多种结构独特的化合物,其中386A是从培养液中分离出的无色晶体,其结构通过波谱数据推导出来.1 实验部分1-1 试剂和仪器 所用试剂均为市售AR试剂,Penicillumsp-(386)菌株由香港城市大学Vrijmoed教授提供.所用仪器为VGZ…  相似文献   
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