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141.
O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) is involved in the regulation of many cellular cascades and neurological diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and stroke. In the brain, the expression of O-GlcNAcylation is notably heightened, as is that of O-linked N-acetylglucosaminyltransferase (OGT) and β-N-acetylglucosaminidase (OGA), the presence of which is prominent in many regions of neurological importance. Most importantly, O-GlcNAcylation is believed to contribute to the normal functioning of neurons; conversely, its dysregulation participates in the pathogenesis of neurological disorders. In neurodegenerative diseases, O-GlcNAcylation of the brain’s key proteins, such as tau and amyloid-β, interacts with their phosphorylation, thereby triggering the formation of neurofibrillary tangles and amyloid plaques. An increase of O-GlcNAcylation by pharmacological intervention prevents neuronal loss. Additionally, O-GlcNAcylation is stress sensitive, and its elevation is cytoprotective. Increased O-GlcNAcylation ameliorated brain damage in victims of both trauma-hemorrhage and stroke. In this review, we summarize the current understanding of O-GlcNAcylation’s physiological and pathological roles in the nervous system and provide a foundation for development of a therapeutic strategy for neurological disorders.  相似文献   
142.
月地高速再入返回器热控设计及实现   总被引:3,自引:0,他引:3  
针对月地高速再入返回器不同阶段大功率散热、小功率保温与高速返回过程中高温隔热之间的突出矛盾,以及狭小、局促空间内设备热量的收集、传输、排散与阻断等技术难题,首次构建一种基于柔性自适应"热开关"的小型再入返回类航天器热控体系,成功研制出一套基于异构式环路热管的一体化柔性、高效热管理系统.在轨飞行数据表明:核心热控产品环路热管控温运行模式下实际传热能力超过65 W,阻断模式下漏热量小于2 W,"热导比"大于30,能够很好地实现"热开关"功能,确保了返回器所有设备的温度水平优于指标要求.  相似文献   
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Lin Z  Bei JX  Shen M  Li Q  Liao Z  Zhang Y  Lv Q  Wei Q  Low HQ  Guo YM  Cao S  Yang M  Hu Z  Xu M  Wang X  Wei Y  Li L  Li C  Li T  Huang J  Pan Y  Jin O  Wu Y  Wu J  Guo Z  He P  Hu S  Wu H  Song H  Zhan F  Liu S  Gao G  Liu Z  Li Y  Xiao C  Li J  Ye Z  He W  Liu D  Shen L  Huang A  Wu H  Tao Y  Pan X  Yu B  Tai ES  Zeng YX  Ren EC  Shen Y  Liu J  Gu J 《Nature genetics》2012,44(1):73-77
To identify susceptibility loci for ankylosing spondylitis, we performed a two-stage genome-wide association study in Han Chinese. In the discovery stage, we analyzed 1,356,350 autosomal SNPs in 1,837 individuals with ankylosing spondylitis and 4,231 controls; in the validation stage, we analyzed 30 suggestive SNPs in an additional 2,100 affected individuals and 3,496 controls. We identified two new susceptibility loci between EDIL3 and HAPLN1 at 5q14.3 (rs4552569; P = 8.77 × 10(-10)) and within ANO6 at 12q12 (rs17095830; P = 1.63 × 10(-8)). We also confirmed previously reported associations in Europeans within the major histocompatibility complex (MHC) region (top SNP, rs13202464; P < 5 × 10(-324)) and at 2p15 (rs10865331; P = 1.98 × 10(-8)). We show that rs13202464 within the MHC region mainly represents the risk effect of HLA-B*27 variants (including HLA-B*2704, HLA-B*2705 and HLA-B*2715) in Chinese. The two newly discovered loci implicate genes related to bone formation and cartilage development, suggesting their potential involvement in the etiology of ankylosing spondylitis.  相似文献   
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Gui Y  Guo G  Huang Y  Hu X  Tang A  Gao S  Wu R  Chen C  Li X  Zhou L  He M  Li Z  Sun X  Jia W  Chen J  Yang S  Zhou F  Zhao X  Wan S  Ye R  Liang C  Liu Z  Huang P  Liu C  Jiang H  Wang Y  Zheng H  Sun L  Liu X  Jiang Z  Feng D  Chen J  Wu S  Zou J  Zhang Z  Yang R  Zhao J  Xu C  Yin W  Guan Z  Ye J  Zhang H  Li J  Kristiansen K  Nickerson ML  Theodorescu D  Li Y  Zhang X  Li S  Wang J  Yang H  Wang J  Cai Z 《Nature genetics》2011,43(9):875-878
Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we discovered a variety of genes previously unknown to be mutated in TCC. Notably, we identified genetic aberrations of the chromatin remodeling genes (UTX, MLL-MLL3, CREBBP-EP300, NCOR1, ARID1A and CHD6) in 59% of our 97 subjects with TCC. Of these genes, we showed UTX to be altered substantially more frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer.  相似文献   
147.
In this paper,we discuss the common fixed point with respect to several self-mappings on fuzzy metric space.Recently many authors put forward some relevant comm...  相似文献   
148.
五味子对心血管、免疫系统及CNS具有调节作用,阐述了五味子中有效成分木脂素和多糖保护心室重构的作用.  相似文献   
149.
A new type of vocoder system based upon formant analysis is presented in this paper. The LMS adaptive algorithm is used for tracking formants of speech signals. The results of computer simulation show that the new vocoder has better synthesized speech quality.  相似文献   
150.
炼油厂废水处理污泥热解制油技术研究   总被引:20,自引:0,他引:20  
对炼油厂废水处理污泥进行了催化热解产油实验,考察了温度(170-300℃)和反应时间(0-90min)对产油率的影响。温度越高,产油率越高,在300℃时,产油率达54.6%,经60min反应接近平衡。讨论了系统质量与能量平衡。  相似文献   
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