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601.
602.
现代湿法炼铜常用硬聚氯乙烯(RPVC)板作为防腐结构材料,本文对硬聚氯乙烯板贮槽渗漏问题进行了分析,提出了相应的防治措施。 相似文献
603.
将模糊自适应PID控制和最佳启停控制相结合应用于智能楼宇中的空调监控系统中,经研究发现运用此方法后,系统的超调小了,而且调节迅速、上升时间短,具有良好的鲁棒性和节能效果。 相似文献
604.
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606.
微波等离子体法制备纳米钼粉 总被引:11,自引:0,他引:11
阐述用微波等离子法制备纳米金属钼粉的原理,探讨了此法制备纳米钼粉颗粒的工艺与影响因素,并以羰基钼为原料制得纳米级钼粉,平均粒径小于50nm,还研究了钼粉在空气中的热稳定性。 相似文献
607.
Patricio Atanes Inmaculada Ruz-Maldonado Ross Hawkes Bo Liu Min Zhao Guo Cai Huang Israa Mohammed Al-Amily Albert Salehi Stefan Amisten Shanta J. Persaud 《Cellular and molecular life sciences : CMLS》2018,75(16):3039-3050
Introduction
Islets synthesise and secrete numerous peptides, some of which are known to be important regulators of islet function and glucose homeostasis. In this study, we quantified mRNAs encoding all peptide ligands of islet G protein-coupled receptors (GPCRs) in isolated human and mouse islets and carried out in vitro islet hormone secretion studies to provide functional confirmation for the species-specific role of peptide YY (PYY) in mouse islets.Materials and methods
GPCR peptide ligand mRNAs in human and mouse islets were quantified by quantitative real-time PCR relative to the reference genes ACTB, GAPDH, PPIA, TBP and TFRC. The pathways connecting GPCR peptide ligands with their receptors were identified by manual searches in the PubMed, IUPHAR and Ingenuity databases. Distribution of PYY protein in mouse and human islets was determined by immunohistochemistry. Insulin, glucagon and somatostatin secretion from islets was measured by radioimmunoassay.Results
We have quantified GPCR peptide ligand mRNA expression in human and mouse islets and created specific signalomes mapping the pathways by which islet peptide ligands regulate human and mouse GPCR signalling. We also identified species-specific islet expression of several GPCR ligands. In particular, PYY mRNA levels were ~ 40,000-fold higher in mouse than human islets, suggesting a more important role of locally secreted Pyy in mouse islets. This was confirmed by IHC and functional experiments measuring insulin, glucagon and somatostatin secretion.Discussion
The detailed human and mouse islet GPCR peptide ligand atlases will allow accurate translation of mouse islet functional studies for the identification of GPCR/peptide signalling pathways relevant for human physiology, which may lead to novel treatment modalities of diabetes and metabolic disease.608.
Kai Zhao Xingyu Zhao Yaping Tu Qi Miao Dongxu Cao Wenjuan Duan Yang Sun Jincheng Wang Taotao Wei Fuyu Yang 《Cellular and molecular life sciences : CMLS》2010,67(15):2665-2678
We have reported that chymotrypsin B (CtrB) is not just a digestive enzyme but is also stored in lysosomes. Herein, we demonstrated a broad distribution of CtrB and explored the involvement of CtrB in apoptosis. Exposure of RH-35 cells to H2O2 or palmitate induced the redistribution of lysosomal CtrB into the cytoplasm as a result of lysosomal membrane permeabilization (LMP). Suppression of CtrB significantly blocked apoptosis, while overexpression of CtrB sensitized apoptosis markedly. CtrB could cleave Bid under neutral conditions. In RH-35 cells with Bid silenced, apoptosis induced by CtrB protein was attenuated, suggesting that CtrB mediates apoptosis of RH-35 cells mainly through processing Bid. Our data also suggest that LMP occurs earlier than mitochondrial outer membrane permeabilization; Bid activation initiated by caspase-8 might be reinforced by CtrB in consequence of LMP, which causes a positive feedback loop leading to the accumulation of tBid, and results in lysosome- and mitochondrion-dependent apoptosis. 相似文献
609.
Genome-wide association studies of 14 agronomic traits in rice landraces 总被引:20,自引:0,他引:20
Huang X Wei X Sang T Zhao Q Feng Q Zhao Y Li C Zhu C Lu T Zhang Z Li M Fan D Guo Y Wang A Wang L Deng L Li W Lu Y Weng Q Liu K Huang T Zhou T Jing Y Li W Lin Z Buckler ES Qian Q Zhang QF Li J Han B 《Nature genetics》2010,42(11):961-967
Uncovering the genetic basis of agronomic traits in crop landraces that have adapted to various agro-climatic conditions is important to world food security. Here we have identified ~ 3.6 million SNPs by sequencing 517 rice landraces and constructed a high-density haplotype map of the rice genome using a novel data-imputation method. We performed genome-wide association studies (GWAS) for 14 agronomic traits in the population of Oryza sativa indica subspecies. The loci identified through GWAS explained ~ 36% of the phenotypic variance, on average. The peak signals at six loci were tied closely to previously identified genes. This study provides a fundamental resource for rice genetics research and breeding, and demonstrates that an approach integrating second-generation genome sequencing and GWAS can be used as a powerful complementary strategy to classical biparental cross-mapping for dissecting complex traits in rice. 相似文献
610.
Genome-wide association study of flowering time and grain yield traits in a worldwide collection of rice germplasm 总被引:9,自引:0,他引:9
Huang X Zhao Y Wei X Li C Wang A Zhao Q Li W Guo Y Deng L Zhu C Fan D Lu Y Weng Q Liu K Zhou T Jing Y Si L Dong G Huang T Lu T Feng Q Qian Q Li J Han B 《Nature genetics》2012,44(1):32-39
A high-density haplotype map recently enabled a genome-wide association study (GWAS) in a population of indica subspecies of Chinese rice landraces. Here we extend this methodology to a larger and more diverse sample of 950 worldwide rice varieties, including the Oryza sativa indica and Oryza sativa japonica subspecies, to perform an additional GWAS. We identified a total of 32 new loci associated with flowering time and with ten grain-related traits, indicating that the larger sample increased the power to detect trait-associated variants using GWAS. To characterize various alleles and complex genetic variation, we developed an analytical framework for haplotype-based de novo assembly of the low-coverage sequencing data in rice. We identified candidate genes for 18 associated loci through detailed annotation. This study shows that the integrated approach of sequence-based GWAS and functional genome annotation has the potential to match complex traits to their causal polymorphisms in rice. 相似文献