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关键词： 桥梁工程   伸缩缝   施工质量   控制  

摘要： 近年来我国工程建筑行业发展前景良好,施工技术不断创新,整体施工质量水平有所提高。公路桥梁项目建设是我国重要的基础工程项目建设,对推进我国道路交通网络完善有着重要作用。就目前我国公路桥梁施工现状来看,桥梁伸缩缝问题是施工控制中的重要问题。随着我国经济规模的不断发展,对交通运输的需要也在不断提高。道路桥梁是运输系统中重要的组成部分,承载着大量的陆路运输和汽车运输的运输需求。因此保证道路桥梁的施工质量,使其能够正常的运行发挥作用,是道桥施工单位的重要责任和义务。在道路桥梁的施工过程中,伸縮缝是其中一个重要的组成分。

关键词： 双预防机制   隐患分级   检查和考核  

摘要： 近年来,我国建筑施工行业生产安全事故起数和死亡人数不断增加,建筑施工企业安全风险分级管控和隐患排查治理双预防机制建设不完善是原因之一。建筑施工企业除了对安全风险进行分级管控,还应对隐患进行分级管理,突出重点隐患,狠抓整改落实。

关键词： Eugenia piauhiensis   gamma-Elemene   Antileishmanial activity   Leishmania amazonensis  

摘要： Leishmaniasis is considered as one of the most Neglected Tropical Diseases (NTDs) in the world, caused by protozoan parasites of the genus Leishmania. Treatment of leishmaniasis by chemotherapy remains a challenge because of limited efficacy, toxic side effects, and drug resistance. The search for new therapeutic agents from natural sources has been a constant for the treatment of diseases such as leishmaniasis. The objective of this study was to evaluate the biological activity of Eugenia piauhiensis Vellaff. essential oil (EpEO) and its major constituent gamma-elemene on promastigote and amastigote forms of Leishmania (Leishmania) amazonensis, its cytotoxicity, and possible mechanisms of action. EpEO was more active (IC50 6.43 +/- 0.18 mu g/mL) against promastigotes than gamma-elemene [9.82 +/- 0.15 mu g/mL (48.05 +/- 0.73 mu M)] and the reference drug miltefosine [IC50 17.25 +/- 0.26 mu g/mL (42.32 +/- 0.64 mu M)]. EpEO and gamma-elemene exhibited low cytotoxicity against J774.A1 macrophages, with CC50 225.8 +/- 3.57 mu g/mL and 213.21 +/- 3.3 mu g/mL (1043 +/- 16.15 mu M), respectively. Additionally, EpEO and gamma-elemene present direct activity against the parasite, decreasing plasma membrane integrity. EpEO and gamma-elemene also proved to be even more active against intracellular amastigotes of the parasite [IC50 4.59 +/- 0.07 mu g/mL and 8.06 +/- 0.12 mu g/mL (39.44 +/- 0.59 mu M)], respectively), presenting indirect effects through macrophage activity modulation. Anti-amastigote activity was associated with increased TNF-alpha, IL-12, NO, and ROS levels. In conclusion, our results suggest EpEO and gamma-elemene as promising candidates for new drug development against leishmaniasis.

关键词： SARS-CoV-2   Infectious diseases   Assays   Cells   COVID-19  

摘要： The coronaviruses disease 2019 (COVID-19) caused by a novel coronavirus (SARS-CoV-2) has become a major health problem, affecting more than 50 million people with over one million deaths globally. Effective antivirals are still lacking. Here, we optimized a high-content imaging platform and the plaque assay for viral output study using the legitimate model of human lung epithelial cells, Calu-3, to determine the anti-SARS-CoV-2 activity of Andrographis paniculata extract and its major component, andrographolide. SARS-CoV-2 at 25TCID(50) was able to reach the maximal infectivity of 95% in Calu-3 cells. Postinfection treatment of A. paniculata and andrographolide in SARS-CoV-2-infected Calu-3 cells significantly inhibited the production of infectious virions with an IC50 of 0.036 mu g/mL and 0.034 mu M, respectively, as determined by the plaque assay. The cytotoxicity profile developed over the cell line representatives of major organs, including liver (HepG2 and imHC), kidney (HK-2), intestine (Caco-2), lung (Calu-3), and brain (SH-SYSY), showed a CC50 of >100 mu g/mL for A. paniculata extract and 13.2-81.5 mu M for andrographolide, respectively, corresponding to a selectivity index of over 380. In conclusion, this study provided experimental evidence in favor of A. paniculata and andrographolide for further development as a monotherapy or in combination with other effective drugs against SARS-CoV-2 infection.

关键词： 道路桥梁工程   伸缩缝   施工质量技术控制  

摘要： 在现阶段的道路桥梁工程中,伸缩缝施工是非常重要的组成部分。伸缩缝由于能调节车辆荷载的差异、热膨胀与冷缩、材料物理性能的差异而得到广泛应用。伸缩缝通常由钢和橡胶制成,它位于桥梁的末端,能将荷载传递到桥梁的主要承重结构上,施工质量直接影响桥梁接缝的安全性和使用寿命。因此,施工过程中务必要加强质量控制。

关键词： 道路桥梁工程   伸缩缝   施工技术  

摘要： 道路桥梁作为城市建设重要的组成部分,对城市正常运行起着重要的作用。伴随着城市化进程不断加速,城市道路桥梁的承载量也逐渐增加,对于这样的民生工程,保障质量是首要的,在保障人们生命安全的前提下完成的道路与桥梁工程才算是有意义的。所以对于道路桥梁工程要足够重视,做好现场施工工作,使得路桥工程质量更上一层,从而满足人们的出行要求。由于桥梁处于室外,很容易产生位移,设置伸缩缝的目的就是为了较少这种位移带来的影响。在现场施工中,道路与桥梁工程的重要性不言而喻,作为工程建设重点项目,伸缩缝作为道路与桥梁工程重要的组成部分,持续受到城市市民的关注,一方面与城市居民生命安全息息相关,另一方面也存在由于伸缩缝问题导致道路与桥梁持续出现问题。既然是道路与桥梁工程中的关键,那么就要明白其重要性。

关键词： 市政路桥工程   伸缩缝施工技术   运用  

摘要： 伴随着我国城市化进程的加快,各个城市中的路桥工程项目日渐增多,各种规模、等级的市政路桥项目建设和实施,不仅完善了城市中的交通网络系统,给人们的出行提供便捷,更是给城市创造了巨大的经济和社会效益。伸缩缝施工虽然在整个市政路桥工程中的工程量较小,但是其施工效果对于整体的工程质量却有着重要的作用,当存在伸缩缝施工的技术性问题时,市政路桥工程的质量、安全都难以保障。基于此,本文详细探析了市政路桥工程项目中的伸缩缝施工技术应用。