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1.
有时我们会被问及这样的问题:你最喜欢一年中的哪段时光?对我来说,春天最令人愉快,大自然从冷漠的冬天中苏醒,生命的力量又开始涌动,树叶生长,蓓蕾绽放,眼前的一切生机盎然,令人赏心悦目。在这大自然生命复苏的时刻,我们的心也为之狂喜,但是美景不会永恒,叶子会到达它生命的极限,花蕾盛开后就会走向枯萎。  相似文献   
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Although feast and famine cycles illustrate that remodelling of adipose tissue in response to fluctuations in nutrient availability is essential for maintaining metabolic homeostasis, the underlying mechanisms remain poorly understood. Here we identify fibroblast growth factor 1 (FGF1) as a critical transducer in this process in mice, and link its regulation to the nuclear receptor PPARγ (peroxisome proliferator activated receptor γ), which is the adipocyte master regulator and the target of the thiazolidinedione class of insulin sensitizing drugs. FGF1 is the prototype of the 22-member FGF family of proteins and has been implicated in a range of physiological processes, including development, wound healing and cardiovascular changes. Surprisingly, FGF1 knockout mice display no significant phenotype under standard laboratory conditions. We show that FGF1 is highly induced in adipose tissue in response to a high-fat diet and that mice lacking FGF1 develop an aggressive diabetic phenotype coupled to aberrant adipose expansion when challenged with a high-fat diet. Further analysis of adipose depots in FGF1-deficient mice revealed multiple histopathologies in the vasculature network, an accentuated inflammatory response, aberrant adipocyte size distribution and ectopic expression of pancreatic lipases. On withdrawal of the high-fat diet, this inflamed adipose tissue fails to properly resolve, resulting in extensive fat necrosis. In terms of mechanisms, we show that adipose induction of FGF1 in the fed state is regulated by PPARγ acting through an evolutionarily conserved promoter proximal PPAR response element within the FGF1 gene. The discovery of a phenotype for the FGF1 knockout mouse establishes the PPARγ–FGF1 axis as critical for maintaining metabolic homeostasis and insulin sensitization.  相似文献   
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The microtubule-associated protein tau (encoded by MAPT) and several tau kinases have been implicated in neurodegeneration, but only MAPT has a proven role in disease. We identified mutations in the gene encoding tau tubulin kinase 2 (TTBK2) as the cause of spinocerebellar ataxia type 11. Affected brain tissue showed substantial cerebellar degeneration and tau deposition. These data suggest that TTBK2 is important in the tau cascade and in spinocerebellar degeneration.  相似文献   
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This article responds to Professor Andrew Janiak's recent attempt to defend the proposition that Isaac Newton did not believe in action at a distance between bodies (or any other kind of substance) (Janiak, 2013). His argument rests on a distinction between “three concepts of causation in Newton”, which leads him to conclude that although Newton did not believe in action at a distance between bodies, he was able to accept that gravity was a “distant action”. I critically examine Janiak's arguments here, and the historical evidence he brings to bear upon it, and argue that Professor Janiak's latest claims do nothing to undermine the view to which he is opposed, namely, that Newton did believe in the possibility of action at a distance between bodies.  相似文献   
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Migraine is a common, heterogeneous and heritable neurological disorder. Its pathophysiology is incompletely understood, and its genetic influences at the population level are unknown. In a population-based genome-wide analysis including 5,122 migraineurs and 18,108 non-migraineurs, rs2651899 (1p36.32, PRDM16), rs10166942 (2q37.1, TRPM8) and rs11172113 (12q13.3, LRP1) were among the top seven associations (P < 5 × 10(-6)) with migraine. These SNPs were significant in a meta-analysis among three replication cohorts and met genome-wide significance in a meta-analysis combining the discovery and replication cohorts (rs2651899, odds ratio (OR) = 1.11, P = 3.8 × 10(-9); rs10166942, OR = 0.85, P = 5.5 × 10(-12); and rs11172113, OR = 0.90, P = 4.3 × 10(-9)). The associations at rs2651899 and rs10166942 were specific for migraine compared with non-migraine headache. None of the three SNP associations was preferential for migraine with aura or without aura, nor were any associations specific for migraine features. TRPM8 has been the focus of neuropathic pain models, whereas LRP1 modulates neuronal glutamate signaling, plausibly linking both genes to migraine pathophysiology.  相似文献   
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