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51.
Risk factors at home for ocular, nasal, throat and dermal symptoms, headache, and fatigue were studied in a nationwide questionnaire survey in Sweden, the BETSI study in 2006. Totally, 5775 adults from a stratified random sample of multi-family buildings participated. Associations between home environment factors and weekly symptoms were analyzed by multi-level logistic regression. In total, 8.3% had ocular symptoms; 11.9% nasal symptoms; 7.1% throat symptoms; 11.9% dermal symptoms; 8.5% headache and 23.1% fatigue. Subjects in colder climate zones had more mucosal and throat symptoms but less fatigue and ocular symptoms. Rented apartments had poorer indoor environment than self-owned apartments. Those living in buildings constructed from 1961 to 1985 had most symptoms. Building dampness, mold and mold odor were risk factors, especially headache and ocular symptoms. Lack of mechanical ventilation system was another risk factor, especially for headache. Environmental tobacco smoke (ETS), electric radiators, and crowdedness were other risk factors. Oiled wooden floors, recent indoor painting, and new floor materials were negatively associated with symptoms. In conclusion, building dampness, mold, poor ventilation conditions, crowdedness, ETS, and emissions from electric radiators in apartments in Sweden can increase the risk of ocular, nasal, throat and dermal symptoms, headache, and fatigue. 相似文献
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53.
Lei He Yan Xuan Feng Zhang Xue Wang Huaqing Pan Junfeng Ren Meina Chen 《International Journal of Hydrogen Energy》2021,46(1):1096-1105
Bulk and surface properties of proton stability and transportation in Y and Nd co-doped BaCeO3 (BCYN), especially the effect of Nd segregation, were investigated by first-principles calculations. Since the structure of doped BaCeO3 at the operating temperature of proton-conducting has been unclear for a long time, we have summarized the latest experimental results and calculated the structure of the asymmetric BCYN for the first time. The results show that compared with Y, Nd doping promotes oxygen vacancy formation, however reduces proton stability. Our calculation can also provide a possible explanation for the formation of space charge layer at the grain boundary of doped BaCeO3 in experiment. Unlike the stable Y in BCYN, Nd is calculated to be easily segregated, which can facilitate both proton hydration and proton transportation near the surface. Moreover, Nd segregation at the grain boundary is predicted to be beneficial for proton transportation between grains. 相似文献
55.
56.
随着计算机技术的快速发展,虚拟仿真技术越发成熟,在教学中的应用越来越广泛.与传统线下实验教学模式相比,虚拟仿真技术具有安全无害,覆盖面广等优点,可以弥补传统实验教学模式中一些不足.本文主要以水银的处理实验为例,展示了虚拟仿真技术在危险性实验教学中的优势,为实验教学知识体系的完整性提供一个有力支持. 相似文献
57.
Osteoporotic fracture with increase of aging population became an urgent orthopedic problem.Bisphos-phonates were widely recommended as effective clinical treatment drugs.Combination of biodegradable Mg-based implants and merits of bisphosphonates was suggested for osteoporotic fracture healing.Considering the mild and sustained drug release,a novel one-step electrodeposition synthesis of drug loaded coating was proposed in this study.In comparison to conventional soaking method,encapsu-lated zoledronate coating by one-step electrodeposition method could modulate drug release in first diffusion-controlled and later degradation-controlled manner.The in vitro cell response to zoledronate loaded coating showed enhanced proliferation and osteogenic differentiation of osteoblasts and no sig-nificant inhibition on osteoclasts,which could improve bone-forming and decrease bone resorption due to osteoporosis. 相似文献
58.
Ting Yu Wen Nie Zehua Hong Yihong He Jing Chen Xue Mi Shuping Yang Xiaoling Li Bilan Wang Yunzhu Lin Xiang Gao 《Advanced functional materials》2021,31(22):2100715
Normalizing the tumor-induced immune deficiency in the immunosuppressive tumor microenvironment (TME) through increasing the efficient infiltration and activation of antitumoral immunity in TME is the core of promising immunotherapy. Herein, a Cyclo(Arg-Gly-Asp-d -Phe-Lys) (RGD) peptides-modified combinatorial immunotherapy system based on the self-assembly of the nanoparticles named RGD-DMA composed of RGD-PEG-PLA, methoxy poly(ethylene glycol)-poly(lactide) (MPEG-PLA) and 1,2-Dioleoyl-3-trimethylammonium-propane (DOTAP) is used to codeliver the immunostimulatory chemokine CCL19-encoding plasmid DNA (CCL19 pDNA) and immune checkpoint ligand PD-L1 inhibitor (BMS-1). The RGD-DMA/pCCL19-BMS-1 system not only exhibited significant inhibition of tumor progression but also induced locally high concentrations of immunostimulatory cytokines at tumor sites without causing an obviously systemic inflammatory response. The immunosuppressive TME is efficaciously reshaped by the coadministration of RGD-DMA/pCCL19 and BMS-1, as indicated by the activated T lymphocytes, increased intratumoral-infiltration of mature dendritic cells (DCs), and the repolarization of macrophages from pro-tumoral M2-phenotype toward tumoricidal M1-phenotype. The upregulated PD-L1 expression at tumor sites caused by the increased IFN-γ levels after immunostimulatory gene therapy further demonstrated the synergistic effects of BMS-1 in counteracting the inhibitory role of PD-L1 expression in antitumor immunity. Therefore, the combination of immunostimulating therapy and immune checkpoint inhibitor that synergistically target multiple immune regulatory pathways demonstrates significant potential as a novel immunotherapy approach. 相似文献
59.
王雪 《昆明冶金高等专科学校学报》2021,37(2):53-57
《民法典》颁布后,思政课应该如何及时地将相关内容融入教学,并使之有效地进入学生头脑?《民法典》内容进课堂对国家法治建设具有怎样的意义?从《民法典》进高职学校所开设的思政课这一视角,探讨《民法典》相关内容融入思政课的必要性,对如何融入教学的整体思考,以及融入教学的切入点和注意事项. 相似文献
60.
Haiyang Chen Bin Li Xue Yang Guangqi Li Hongqiang Chen Junhong Chen Bo Ren 《Ceramics International》2021,47(16):22911-22917
Understanding the spheroidization process of micron-scaled α-Al2O3 powder in hydrothermal method is of great importance but still not completely revealed. The results demonstrated that SO42? played a significant role in the formation of spherical powder, while the bubble generated from the reaction of urea didn't work in the spheroidization process. The spheroidization process was summed up as two steps. The first was that SO42? limited the hydrolysis of Al3+ and reacted with Al3+ and OH- to form Al4(OH)10SO4, which nucleated and agglomerated into granular precipitates. The second was Ostwald ripening, which gave the spherical precursors a double-layered structure. When the spherical precursors obtained 120 °C were sintered at 1200 °C, α-Al2O3 were got and the spherical morphology still maintained with a large number of nano-sized pores. We anticipate the spherical α-Al2O3 with nano-sized pores can be applied in adsorption and filtration industries. 相似文献