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11.
采用一种恰当的方法,简便地推导出中子输运方程泄漏项在球坐标系下的表达式,该方法避免直接寻求二面角与中子飞行距离之间的复杂微分关系,转而寻求二面角与其他平面角之间的几何关系,再利用其他平面角与中子飞行距离之间的微分关系(通常是已知的或比较容易推导得到),便可间接推导出中子输运方程泄漏项在球坐标系下的表达式。该方法与传统方法推导得到的表达式完全一致,且推导过程直观、物理图像清晰。  相似文献   
12.
智慧建造的特点就在于依靠IT技术、云技术、新型建造设备等传统建造不具备的资源,达到减少重复性人力劳动的目的,使建造过程处于智能技术的精准控制下,解决了人力难以甚至无法达到的高效建造模式。在位于江西省景德镇市的景德镇御窑博物馆项目中,中建一局团队利用了无人机、Hololens全息眼镜、智能放样机器人以及三维激光扫描仪等智能建造设备,整合出了一套质量控制全过程全过程质量控制的解决方案。  相似文献   
13.
Chloroquine (CQ) is an antimalaria drug that has been widely used for decades. However, CQ-induced pruritus remains one of the major obstacles in CQ treatment for uncomplicated malaria. Recent studies have revealed that MrgprX1 plays an essential role in CQ-induced itch. To date, a few MrgprX1 antagonists have been discovered, but they are clinically unavailable or lack selectivity. Here, a cell-based high-throughput screening was performed to identify novel antagonists of MrgprX1, and the screening of 2543 compounds revealed two novel MrgprX1 inhibitors, berbamine and closantel. Notably, berbamine potently inhibited CQ-mediated MrgprX1 activation (IC50 = 1.6 μM) but did not alter the activity of other pruritogenic GPCRs. In addition, berbamine suppressed the CQ-mediated phosphorylation of ERK1/2. Interestingly, CQ-induced pruritus was significantly reduced by berbamine in a dose-dependent manner, but berbamine had no effect on histamine-induced, protease-activated receptors 2-activating peptide-induced, and deoxycholic acid-induced itch in mice. These results suggest that berbamine is a novel, potent, and selective antagonist of MrgprX1 and may be a potential drug candidate for the development of therapeutic agents to treat CQ-induced pruritus.  相似文献   
14.
Prostate cancer (PCa) is a common malignant cancer of the urinary system. Drug therapy, chemotherapy, and radical prostatectomy are the primary treatment methods, but drug resistance and postoperative recurrence often occur. Therefore, seeking novel anti-tumor compounds with high efficiency and low toxicity from natural products can produce a new tumor treatment method. Matijin-Su [N-(N-benzoyl-L-phenylalanyl)-O-acetyl-L-phenylalanol, MTS] is a phenylalanine dipeptide monomer compound that is isolated from the Chinese ethnic medicine Matijin (Dichondra repens Forst.). Its derivatives exhibit various pharmacological activities, especially anti-tumor. Among them, the novel MTS derivative HXL131 has a significant inhibitory effect against prostate tumor growth and metastasis. This study is designed to investigate the effects of HXL131 on the growth and metastasis of human PCa cell lines PC3 and its molecular mechanism through in vitro experiments combined with proteomics, molecular docking, and gene silencing. The in vitro results showed that HXL131 concentration dependently inhibited PC3 cell proliferation, induced apoptosis, arrested cell cycle at the G2/M phase, and inhibited cell migration capacity. A proteomic analysis and a Western blot showed that HXL131 up-regulated the expression of proliferation, apoptosis, cell cycle, and migration-related proteins CYR61, TIMP1, SOD2, IL6, SERPINE2, DUSP1, TNFSF9, OSMR, TNFRSF10D, and TNFRSF12A. Molecular docking, a cellular thermal shift assay (CETSA), and gene silencing showed that HXL131 had a strong binding affinity with DUSP1 and TNFSF9, which are important target genes for inhibiting the growth and metastasis of PC3 cells. This study demonstrates that HXL131 exhibited excellent anti-prostate cancer activity and inhibited the growth and metastasis of prostate cancer cells by regulating the expression of DUSP1 and TNFSF9.  相似文献   
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16.
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal interstitial lung disease with unknown etiology. Despite substantial progress in understanding the pathogenesis of pulmonary fibrosis and drug development, there is still no cure for this devastating disease. Fenbendazole (FBZ) is a benzimidazole compound that is widely used as an anthelmintic agent and recent studies have expanded the scope of its pharmacological effects and application prospect. This study demonstrated that FBZ treatment blunted bleomycin-induced lung fibrosis in mice. In vitro studies showed that FBZ inhibited the proliferation and migration of human embryo lung fibroblasts. Further studies showed that FBZ significantly inhibited glucose consumption, moderated glycolytic metabolism in fibroblasts, thus activated adenosine monophosphate-activated protein kinase (AMPK), and reduced the activation of the mammalian target of rapamycin (mTOR) pathway, thereby inhibiting transforming growth factor-β (TGF-β1)-induced fibroblast-to-myofibroblast differentiation and collagen synthesis. In summary, our data suggested that FBZ has potential as a novel treatment for pulmonary fibrosis.  相似文献   
17.
To endow the polymeric prodrug with smart properties through a safe and simple method, matrix metalloproteinase (MMPs) responsive peptide GPLGVRGDG was introduced into the block copolymer to prepare TPGS3350-GPLGVRGDG-DOX&DOX micelles, where TPGS3350 is D-α-tocopheryl polyethylene glycol 3350 succinate. During the doxorubicin delivery, the cleavage of the peptide chain triggers de-PEGylation, and the remaining VRGDG sequence was retained on the surface of the micelles, which can act as a ligand to facilitate cell uptake. Moreover, the cytotoxicity of TPGS3350-GPLGVRGDG-DOX&DOX micelles against 4T1 cells was significantly improved, compared with TPGS3350-GPLGVRG-DOX&DOX micelles and TPGS3350-DOX&DOX micelles. During in vivo studies, TPGS3350-GPLGVRGDG-DOX&DOX micelles exhibited good anticancer efficacy with long circulation in the body and more efficient accumulation at the tumor site. Therefore, TPGS3350-GPLGVRGDG-DOX&DOX micelles have improved antitumor activity and reduced toxic side effects. This work opens new potential for exploring the strategy of drug delivery in clinical applications.  相似文献   
18.
针对国内应用性本科高校教学改革中BIM课程体系不完善的问题,将OBE教育理念及CDIO工程教育模式引入土木工程课程教学中。以一体化BIM课程体系建设为中心,以结果为导向,构建了基于OBE-CDIO理念的BIM工程能力人才培养模型。围绕制定的BIM能力培养目标,以项目案例驱动开展基于建筑信息模型网络云平台的课程教学实践及教学评价,建立土木工程专业BIM课程教学体系。教学实践证明:OBE-CDIO理念下的BIM教学体系能有效提高毕业生BIM综合工程应用能力和创新能力,为应用型本科院校的BIM教学改革提供参考。  相似文献   
19.
The development of Ni-based single crystal superalloys relies heavily on the composition design with the addition of critical alloying elements,e.g.,Re and Ru.Understanding the role of alloying effects require to know the configurations of the alloying element distribution betweenγ-Ni andγ′-Ni_3Al phases and among various non-equivalent sites.This work employed firstprinciples density functional theory calculations to study the preference of phase and site occupancy of 11 alloying elements including Al and transition metal elements:3d (Ti,Cr,Co,Ni),4d (Mo,Ru),and 5d (Hf,Ta,W,Re) in Ni and Ni_3Al.We calculated the substitution energies of 1298 triple-site doping configurations including 286 Ni Ni Ni site doping of Ni,726 Al Ni Ni site doping,and 286 Ni Ni Ni site doping of Ni_3Al with alloying elements Ni,Co,Ru,Cr,Re,Mo,W,Al,Ti,Ta,and Hf.In the dual-site and triple-site doping of Ni and Ni_3Al,all studied alloying elements preferred to occupy Ni phase rather than Ni_3Al phase.We found that the most stable defect complexes often contained the favorable substitutions of Al,Ti,Ta,and Hf for the Ni sites that stabilized the alloying elements doping at the other one or two nearest neighbor sites.The co-substitutions of various alloying elements at multiple sites are critical to understanding the strengthening mechanism of alloying elements in Ni-based single crystal superalloys.  相似文献   
20.
传统的优化方法在描述能力、建模方法、方法实现和模型数据的分析等方面都存在着局限性,需要引入新的思路.针对上述问题,提出了基于知识的广义优化方法,给出了广义优化中知识概念、优化问题的描述,以及基于知识的广义优化方法的一般求解过程.其基本方法是在优化问题知识模型的基础上,建立基于知识的广义优化算法,通过知识系统的约简,得到用于制定优化方案的决策规则.同时给出了基于知识的广义优化方法在在锅炉燃烧优化问题中的应用示例,说明了方法的有效性.  相似文献   
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