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Gastric cancer is a serious malignancy that endangers human health. Increased rates of chemotherapy-resistant cancer have led to a decrease in the efficacy of treatment. Recent studies found that the presence of hypoxia in the tumor microenvironment was a notable cause of gastric cancer resistance to chemotherapy drugs. The abnormal structure and function of blood vessels in the tumor and the rapid proliferation of tumor cells increase the oxygen consumption of tumor cells, which results in tumor tissue hypox-ia. Hypoxic conditions make tumor cells more aggressive, more likely to metastasize and develop resistance to chemotherapy. In this paper, we have reviewed the progress of research into hypoxia-induced chemotherapeutic drug resistance in gastric cancer. The review has covered the causes of hypoxia and the characteristics of the hypoxic microenvironment in gastric cancer, the current situation and causes of hypoxia-induced chemotherapeutic drug resistance in gastric cancer, and the measures to overcome the hypoxia-induced re-sistance to chemotherapy drugs.
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Objective To examine whether electroacupuncture at the Wangu acupoint (GB 12 ) , whose position is similar to the cerebellar fastigial nucleus ,can reduce inflammatory cytokines in the hippocampus of rats with vascular dementia (VD) to provide theoretical evidence for treating VD with electroacupuncture .Methods Healthy Sprague‐Dawley rats ( n=54 ,300 -450 g) were randomly divided into three groups :sham surgery group ,VD group ,and electroacupuncture group .The ethologic scores of VD rats were evaluated and the mRNA expressions of inflammatory cytokines (TNF‐α,IL‐6 and IL‐1β) in the hippocampus were assessed and the hippocampal tissues were observed by hematoxylin‐eosin (HE) staining .Results Compared with VD group ,in electroacupuncture group the rats' learning ability improved significantly and the mRNA expressions of TNF‐α, IL‐6 and IL‐1β decreased . Simultaneously ,the damage extent of nerve cells in the hippocampal tissues decreased , and their morphology recovered to nearly normal .Conclusion Electroacupuncture at the Wangu acupoint can decrease the level of inflammatory cytokines in the hippocampus and reduce the damage extent of nerve cells in the hippocampus ,thus providing a new neuroprotective method for VD .
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We report a simple method to produce a stable and repeatable photoanode for water splitting with a core-shell hematite (α-Fe2O3) nanorods system by combining spray pyrolysis and hydrothermal synthesis. Impedance spectroscopy revealed passivation of the surface states by the shell layer, which results in an increase of the charge injection through the hematite conduction band. In pristine hematite more holes are accumulated on the surface and the charge transfer to the electrolyte occurs through surface states, whereas in the core-shell hematite photoanode the majority of hole transfer process occurs through the valence band. As a result the photoactivity of the core-shell nanorods, 1.2 mA cm(-2), at 1.23 V vs RHE, is twice that of pristine hematite nanorods. The alteration of the interface energetics is supported by TEM, showing that the crystallinity of the surface has been improved by the deposition of the shell.
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Infiltration of mesoporous TiO2 scaffolds by CH3NH3PbI3 is more complete when using sequential compared to single step deposition processing and avoids formation of disordered capping layers affording greatly improved performance of perovskite based photovoltaics.
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Adhesion molecules are involved in neutrophil-mediated inflammation. Neutropil adhesion to endothelial cell mediated by cell adhesion molecules (CAMs) is the first and critical step during the process of inflammation. Three families of CAMs play a central role in neutrophil-endothe-lial cell interactions : the selectins, the integrins, and the immunoglobulin superfamily. These different types of CAMs interact in a programmed, sequential manner to form neutrophil-endothelial cell adhesion cascade. The initial phase of inflammation, neulrophil slowing and rolling, is mediated by selectins; subsequently, firm adhesion of neu-trophils to vessel endothelial cells occurs via binding of the activated integrins and the endothelial receptors such as intercellular adhesion molecule-1 (ICAM-1); Then, neutrophils transmigrate into the tissues, this process requires chemotactic factors, integrins and PEC AM-1. Because of the important role of CAMs in the process of inflammation. Agents may be used to block the function of CAMs as a strategy of antiinflammatory therapy.