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61.
白集煤矿以其采深大、地压地温高、通风系统线路长、提升运输环节多等复杂条件而著称于苏北矿区。作为一座地方中小型矿井,始终没有放弃创新发展的机会。依靠科技进步,解决安全难题,创建高产高效矿井。 相似文献
62.
63.
Chen J Luo Y Hong L Ling Y Pang J Fang Y Wei K Gao X 《Journal of materials science. Materials in medicine》2011,22(3):547-555
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited
bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite
(PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine
that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique,
which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the
PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency
of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of
these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL
microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion,
by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as
an injectable vehicle for local therapy of bone defect. 相似文献
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Plants have various self-defense mechanisms against biotic attacks, involving both physical and chemical barriers. Physical barriers include spines, trichomes, and cuticle layers, whereas chemical barriers include secondary metabolites (SMs) and volatile organic compounds (VOCs). Complex interactions between plants and herbivores occur. Plant responses to insect herbivory begin with the perception of physical stimuli, chemical compounds (orally secreted by insects and herbivore-induced VOCs) during feeding. Plant cell membranes then generate ion fluxes that create differences in plasma membrane potential (Vm), which provokes the initiation of signal transduction, the activation of various hormones (e.g., jasmonic acid, salicylic acid, and ethylene), and the release of VOCs and SMs. This review of recent studies of plant–herbivore–infection interactions focuses on early and late plant responses, including physical barriers, signal transduction, SM production as well as epigenetic regulation, and phytohormone responses. 相似文献
66.
随着水利水电建设工程不断向坝体高、规模大、结构复杂及工期要求紧、质量安全要求高的方向发展,施工的复杂性、难度性和风险性不断增加。工程建设与工程所在地居民安全、生活环境之问的关系愈加密切,各种人文、社会和环境方面的矛盾和问题时常出现。党和政府提出的构建和谐社会的战略纲领,为工程项目建设和谐工地指明了方向。 相似文献
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69.
Na Li Guangyi Liu Huimin Zhang Quan Zhao Yun Zhao Zhou Tong Yingying Wang Junshuai Sun 《中国通信》2022,(3):1-15
The convergence of information, communication, and data technologies(ICDT) has been identified as one of the developing trends of the sixth generation(6G) network. Service-based architecture(SBA) as one of the promising information technology, has been preliminarily introduced into the fifth generation(5G) core network(CN) and successfully commercialized, which verifies its feasibility and effectiveness. However, SBA mainly focuses on the control plane of CN at present and the SBA-CN user plane ... 相似文献
70.
苏蕴 《数字社区&智能家居》2010,(9X):7730-7731
JSP技术的应用越来越广泛,特别是在Web数据库开发中体现出强大的优势,该文介绍了JSP实现Web数据库开发的两种模式,以及以JDBC为基础的Web数据库的实现。 相似文献