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排序方式: 共有6515条查询结果,搜索用时 15 毫秒
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Induction of autophagy by an oleanolic acid derivative,SZC017, promotes ROS‐dependent apoptosis through Akt and JAK2/STAT3 signaling pathway in human lung cancer cells 下载免费PDF全文
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Zi Shi Wei Song Jinfeng Xing Minxiao Duan Fengge Wang Hongli Tian Liwen Xu Shuaishuai Wang Aiguo Su Chunhui Li Ruyang Zhang Yanxin Zhao Meijie Luo Jidong Wang Jiuran Zhao 《Molecular breeding : new strategies in plant improvement》2017,37(9):108
Kernel size and kernel weight are important factors possibly involved in the determination of grain yield in maize, so identifying the genetic basis of kernel-related traits provides insights into the breeding of high-yield maize varieties. Kernel length (KL), kernel width (KW) and hundred kernel weight (HKW) were evaluated in three various planting conditions for the 240 field-grown double haploid (DH) lines derived from the single-cross hybrid Xianyu335. Variations in KL, KW and HKW were observed among DH lines, and all three traits showed a broad sense heritability of 76%. A total of 964 single nucleotide polymorphisms (SNPs) from the MaizeSNP3072 chip was utilised to create a high-density genetic map of 1546.4 cM and to identify quantitative trait loci (QTLs). Using composite interval mapping, a total of five, seven and five QTLs have been mapped for KL, KW and HKW, respectively. qkl1-2 and qkl4-1 explained 17.8% and 14.2% of the phenotypic variation in KL, respectively, and the other three QTLs contributed 3.2–4.0%. The phenotypic variation explained (PVE) of seven QTLs responsible for KW ranged from 3.3 to 9.5%. Three QTLs for HKW, qhkw1, qhkw5 and qhkw10 each explained more than 10% of the phenotypic variation, and qhkw4 and qhkw9 accounted for 3.0% and 6.0%, respectively. Due to their detection in multiple planting environments, the loci mapped here appear to be potential targets for the improvement of maize grain yield. 相似文献
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Li Lulu An Meiling Qu Changfeng Zheng Zhou Wang Yibin Liu Fangming He Yingying He Xiaodong Miao Jinlai 《Extremophiles : life under extreme conditions》2017,21(4):817-827
Extremophiles - Major intrinsic proteins (MIPs) form channels facilitating the passive transport of water and other small polar molecules across membranes. In this study, the complete open reading... 相似文献
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Uncoupling associations of risk alleles with endophenotypes and phenotypes: insights from the ApoB locus and heart‐related traits 下载免费PDF全文
Alexander M. Kulminski Yelena Kernogitski Irina Culminskaya Yury Loika Konstantin G. Arbeev Olivia Bagley Matt Duan Liubov Arbeeva Svetlana V. Ukraintseva Deqing Wu Eric Stallard Anatoliy I. Yashin 《Aging cell》2017,16(1):61-72
Traditionally, genomewide association studies (GWAS) have emphasized the benefits of large samples in the analyses of age‐related traits rather than their specific properties. We adopted a realistic concept of genetic susceptibility to inherently heterogeneous, age‐related traits driven by the elusive role of evolution in their properties. We analyzed in detail the associations of rs693 and rs562338 polymorphisms representing the Apolipoprotein B locus with endophenotypes (total cholesterol [TC] and high‐density lipoprotein cholesterol) and phenotypes (myocardial infarction [MI] and survival) in four large‐scale studies, which include 20 748 individuals with 2357 MI events. We showed that a strong, robust predisposition of rs693 and rs562338 to TC (β = 0.72, P = 7.7 × 10?30 for rs693 and β = ?1.08, P = 9.8 × 10?42 for rs562338) is not translated into a predisposition to MI and survival. The rs693_A allele influences risks of MI and mortality after MI additively with lipids. This allele shows antagonistic effects—protecting against MI risks (β = ?0.18, P = 1.1 × 10?5) or increasing MI risks (β = 0.15, P = 2.8 × 10?3) and mortality after MI, in different populations. Paradoxically, increased TC concentrations can be protective against MI for the rs693_A allele carriers. Our results uncouple the influences of the same alleles on endophenotypes and phenotypes despite potential causal relationships among the latter. Our strategy reveals virtually genomewide significance for the associations of rs693 with MI (P = 5.5 × 10?8) that is contrasted with a weak estimate following the traditional, sample‐size‐centered GWAS strategy (P = 0.16) in the same sample. These results caution against the use of the traditional GWAS strategy for gaining profound insights into genetic predisposition to healthspan and lifespan. 相似文献
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Falin Xu Qiongdan Bai Kai Zhou Li Ma Jiajia Duan Fangli Zhuang 《Electromagnetic biology and medicine》2017,36(2):158-166
To investigate the effects of exposure to an 1800 MHz electromagnetic field on cell death and cell proliferation in the developing brain, postnatal day 7 (P7) and P21 healthy Kunming mice were randomly assigned into the experimental and control groups. The experimental groups were exposed to an 1800 MHz electromagnetic field for 8 h daily for three consecutive days. The thymidine analog 5-bromo-2-deoxyuridine (BrdU) was injected intraperitoneally 1 h before each exposure session, and all animals were sacrificed 24 h after the last exposure. Cell death and proliferation markers were detected by immunohistochemistry in the dentate gyrus of the hippocampus. Electromagnetic exposure has no influence on cell death in the dentate gyrus of the hippocampus in P7 and P21 mice as indicated by active caspase-3 immunostaining and Fluoro-Jade labeling. The basal cell proliferation in the hippocampus was higher in P7 than in P21 mice as indicated by the number of cells labeled with BrdU and by immunohistochemical staining for phosphor-histone H3 (PHH3) and brain lipid-binding protein (BLBP). Electromagnetic exposure stimulated DNA synthesis in P7 neural stem and progenitor cells, but reduced cell division and the total number of stem cells in the hippocampus as indicated by increased BrdU labeling and reduced PHH3 and BLBP labeling compared to P7 control mice. There were no significant changes in cell proliferation in P21 mice after exposure to the electromagnetic field. These results indicate that interference with stem cell proliferation upon short-term exposure to an 1800 MHz electromagnetic field depends on the developmental stage of the brain. 相似文献
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Yunran Zhai Lingyan Meng Lijun Xu Lin Yuan Zhilin Yang Jiawen Hu Xiangfeng Duan 《Plasmonics (Norwell, Mass.)》2017,12(2):263-269
Fluorescence intensity is vital for fluorescence sensing and imaging because it determines the sensing sensitivity and imaging brightness. This study reports plasmon-enhanced fluorescence by engineering plasmonic nanostructures, that are SiO2-coated Au nanoshell dimers with a high yield exceeding 60 %. With this elaborately designed nanostructure, we show that the thin SiO2 shell can conveniently distance the fluorophore from the underneath metal, thereby effectively avoiding fluorescence quenching. Meanwhile, the inner Au nanoshell dimers create abundant hot spots at particle-particle junctions and enable near-infrared fluorescence enhancement. The largest fluorescence enhancement achieved is 69 times for the design with a 9 nm external SiO2 shell, as is also confirmed by three-dimensional finite-difference time-domain simulations. This dramatically increased fluorescence has great significance in fluorescence-based sensing and imaging. 相似文献