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191.
Opisthorchis viverrini-related cholangiocarcinoma (CCA), a fatal bile duct cancer, is a major public health concern in areas endemic for this parasite. We report here whole-exome sequencing of eight O. viverrini-related tumors and matched normal tissue. We identified and validated 206 somatic mutations in 187 genes using Sanger sequencing and selected 15 genes for mutation prevalence screening in an additional 46 individuals with CCA (cases). In addition to the known cancer-related genes TP53 (mutated in 44.4% of cases), KRAS (16.7%) and SMAD4 (16.7%), we identified somatic mutations in 10 newly implicated genes in 14.8-3.7% of cases. These included inactivating mutations in MLL3 (in 14.8% of cases), ROBO2 (9.3%), RNF43 (9.3%) and PEG3 (5.6%), and activating mutations in the GNAS oncogene (9.3%). These genes have functions that can be broadly grouped into three biological classes: (i) deactivation of histone modifiers, (ii) activation of G protein signaling and (iii) loss of genome stability. This study provides insight into the mutational landscape contributing to O. viverrini-related CCA.  相似文献   
192.
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   
193.
The cartoon animation industry has developed into a huge industrial chain with a large potential market involving games, digital entertainment, and other industries. However, due to the coarse-grained classification of cartoon materials, cartoon animators can hardly find relevant materials during the process of creation. The polar emotions of cartoon materials are an important reference for creators as they can help them easily obtain the pictures they need. Some methods for obtaining the emotions of cartoon pictures have been proposed, but most of these focus on expression recognition. Meanwhile, other emotion recognition methods are not ideal for use as cartoon materials. We propose a deep learning-based method to classify the polar emotions of the cartoon pictures of the "Moe" drawing style. According to the expression feature of the cartoon characters of this drawing style, we recognize the facial expressions of cartoon characters and extract the scene and facial features of the cartoon images. Then, we correct the emotions of the pictures obtained by the expression recognition according to the scene features. Finally, we can obtain the polar emotions of corresponding picture. We designed a dataset and performed verification tests on it, achieving 81.9% experimental accuracy. The experimental results prove that our method is competitive.  相似文献   
194.
文章结合运行调整,分析了300 MW直接空冷机组,锅炉采用中储式制粉系统运行中因给粉机叶轮孔板销子脱落,煤粉自流引起煤粉管道堵塞对机组安全运行的影响,通过对故障现象的分析,介绍了故障诊断及处理过程.  相似文献   
195.
采用氨基酸钠游离的氨基引发ε-己内酯单体开环得到酯肽齐聚物,并以六亚甲基二异氰酸酯为扩链剂,将这些齐聚物扩链合成4种聚酯酰胺.将4种天然氨基酸(L-丙氨酸、L-亮氨酸、L-谷氨酸、L-赖氨酸)引入到聚(ε-己内酯)(poly(ε-caprolactone),PCL)中,合成和表征了4种含有氨基酸残基的聚合物.通过1H-NMR、FT-IR、水接触角、水吸收率和降解实验对该聚酯酰胺进行了表征.实验结果表明:经氨基酸改性PCL的亲水性和降解性得到了改善,其中含有L-赖氨酸残基的聚酯酰胺因亲水性最高,降解速率最快.  相似文献   
196.
人力资源是21世纪市场经济中最重要的竞争力,而建筑施工企业的人力资源仍存在许多问题,必将制约该行业的发展.文章从人力资源管理与开发的理论出发,阐述了建筑施工业中人力资源的现状,分析了现状背后的原因,并提出了相应的对策建议.  相似文献   
197.
Large-area single-or multilayer graphene of high quality is synthesized on Ni films by radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) at a relatively low temperature (650℃).In the deposition process,a trace amount of CH4 gas (2-8 sccm (sccm denotes standard cubic centimeter per minute at STP)) is introduced into the PECVD chamber and only a short deposition time (30-60 s) is used.Single-or multilayer graphene is obtained because carbon atoms from the discharging CH4 diffuse into the Ni film and then segregate out at its surface.The layer number of the obtained graphene increases when the deposition time or CH4 gas flow rate is increased.This investigation shows that PECVD is a simple,low-cost,and effective technique to synthesize large-area single-or multilayer graphene,which has potential for application as electronic devices.  相似文献   
198.
Empirical research on the business value of IT has often been underpinned by the indispensable tenet of resource complementarity in the resource-based view (RBV) and the crucial concept of fit rooted in contingency theory. Increasingly, it has been recognised that IT needs to be integrated with other organisational factors to create business value. However, empirical studies differ in varying degrees from what organisational factors to be examined and their research findings, but also have been largely biased towards examining pairwise relationships between IT and organisational factors. This paper argues that IT is an integral part of a system of interrelated organisational factors and that a holistic approach is required to further understand when, how and why IT creates business value. After summarising what has been learnt from empirical studies of IT business value, this paper discusses the key conceptual issues of internal fit and resource complementarity as currently conceptualised and employed in the research domain. In order to continue advancing knowledge, this paper argues for and presents a contingency RBV to provide an alternative conceptualisation of IT business value. Essentially, the contingency RBV conjectures that the level of IT business value depends on the interaction of a whole system subject simultaneously to multiple moderators and mediators. Finally, this paper concludes with a discussion of the value of the contingency RBV and its implications for future research.  相似文献   
199.
我们证明了孙智伟的下述猜想:对任意不等于3的正整数n,存在{1,2,dos,n)的一个全排列(a_1,…,a_n)使得a_1=1,a_n=n,并且a_1+a_2,a_2+a_3,…,a_(n-1)+a_n,a_n+a_1都与n互素  相似文献   
200.
首先指出目前我国出现的大城市将市域范围全部纳入规划区的现象,阐述经济落后地区不适合采取大城市的做法的原因,接着分析了<城乡规划法>规定的规划区的内涵,指出我国目前规划区划定存在的主要问题,最后以安徽省涡阳县为例,小议对经济落后地区规划区范围界定的研究和认识.  相似文献   
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