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关键词： 塔头狭叶黄芩   抗旱   耐贫瘠   屋顶绿化  

摘要： 塔头狭叶黄芩是唇形科黄芩属植物,通过在北京地区引种观测,总结出其栽培技术。塔头狭叶黄芩在露地种植生长过程中易养护,表现出较好的抗旱、耐贫瘠、覆地效果佳等性状,作为绿化植被在园林应用尤其是屋顶绿化的应用有着广阔的前景。

关键词： Wnt/beta-catenin signalling   beta-catenin destruction complex   adenomatous polyposis coli (APC)   axis inhibition protein (AXIN)   glycogen synthase kinase 3 (GSK3)   casein kinase 1 (CK1)   SCFβ-TrCP   biochemistry   ubiquitin   colorectal cancer  

摘要： The Wnt/beta-catenin pathway is a highly conserved, frequently mutated developmental and cancer pathway. Its output is defined mainly by beta-catenin's phosphorylation- and ubiquitylation-dependent proteasomal degradation, initiated by the multi-protein beta-catenin destruction complex. The precise mechanisms underlying destruction complex function have remained unknown, largely because of the lack of suitable in vitro systems. Here we describe the in vitro reconstitution of an active human beta-catenin destruction complex from purified components, recapitulating complex assembly, beta-catenin modification, and degradation. We reveal that AXIN1 polymerization and APC promote beta-catenin capture, phosphorylation, and ubiquitylation. APC facilitates beta-catenin's flux through the complex by limiting ubiquitylation processivity and directly interacts with the SCF beta-TrCP E3 ligase complex in a beta-TrCP-dependent manner. Oncogenic APC truncation variants, although part of the complex, are functionally impaired. Nonetheless, even the most severely truncated APC variant promotes beta-catenin recruitment. These findings exemplify the power of biochemical reconstitution to interrogate the molecular mechanisms of Wnt/beta-catenin signaling.

关键词： Acute myeloid leukaemia   Target identification  

摘要： Despite the fact that AML is the most common acute leukemia in adults, patient outcomes are poor necessitating the development of novel therapies. We identified that inhibition of Thioredoxin Reductase (TrxR) is a promising strategy for AML and report a highly potent and specific inhibitor of TrxR, S-250. Both pharmacologic and genetic inhibition of TrxR impairs the growth of human AML in mouse models. We found that TrxR inhibition leads to a rapid and marked impairment of metabolism in leukemic cells subsequently leading to cell death. TrxR was found to be a major and direct regulator of metabolism in AML cells through impacts on both glycolysis and the TCA cycle. Studies revealed that TrxR directly regulates GAPDH leading to a disruption of glycolysis and an increase in flux through the pentose phosphate pathway (PPP). The combined inhibition of TrxR and the PPP led to enhanced leukemia growth inhibition. Overall, TrxR abrogation, particularly with S-250, was identified as a promising strategy to disrupt AML metabolism.

关键词： Pareto distribution   lifetime performance index   general progressive type II censoring   Bayesian estimation   MCMC  

摘要： In this paper, we study the statistical inference for the lifetime performance index of the Pareto distribution based on the general progressive type II censored data. Through data transformation, we derive the maximum likelihood estimator (MLE) of lifetime performance index and confidence interval. Further, the Bayesian estimator and the associated credible interval based on informative and non informative prior functions are also considered under the squared error loss function. Based on the non Bayesian and Bayesian estimators of lifetime performance indicators, the hypothesis testing process is constructed to evaluate the life performance of products. After the Monte Carlo simulation, we find that the Bayesian estimator is far better than MLE, and the Bayesian estimator based on informative prior has the best performance. The estimated mean squared errors for both MLE and Bayesian estimator are small, indicating that our considered method is effective to assess the lifetime performance of the products. Finally, a numerical example is analyzed for illustrative purposes.

关键词： 预制中隔墙   六自由度   平行四边形起升  

摘要： 本文以国外某单洞双线隧道为研究背景,研发了一种履带行走、平行四杆起升的预制中隔墙拼装机械,实现了预制中隔墙拼装操作简单、安全可靠。