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991.
Ya Qi Cheng Shou Bi Wang Jia Hui Liu Lin Jin Ying Liu Chao Yang Li Ya Ru Su Yu Run Liu Xuan Sang Qi Wan Chang Liu Liu Yang Zhi Chong Wang 《Cell proliferation》2020,53(8)
The tumour microenvironment (TME) plays a pivotal role in tumour fate determination. The TME acts together with the genetic material of tumour cells to determine their initiation, metastasis and drug resistance. Stromal cells in the TME promote the growth and metastasis of tumour cells by secreting soluble molecules or exosomes. The abnormal microenvironment reduces immune surveillance and tumour killing. The TME causes low anti‐tumour drug penetration and reactivity and high drug resistance. Tumour angiogenesis and microenvironmental hypoxia limit the drug concentration within the TME and enhance the stemness of tumour cells. Therefore, modifying the TME to effectively attack tumour cells could represent a comprehensive and effective anti‐tumour strategy. Normal cells, such as stem cells and immune cells, can penetrate and disrupt the abnormal TME. Reconstruction of the TME with healthy cells is an exciting new direction for tumour treatment. We will elaborate on the mechanism of the TME to support tumours and the current cell therapies for targeting tumours and the TME—such as immune cell therapies, haematopoietic stem cell (HSC) transplantation therapies, mesenchymal stem cell (MSC) transfer and embryonic stem cell‐based microenvironment therapies—to provide novel ideas for producing breakthroughs in tumour therapy strategies. 相似文献
992.
目的:探讨沙丁胺醇、布地奈德不同雾化吸入联合头孢哌酮钠舒巴坦钠对慢性阻塞性肺疾病急性加重期(AECOPD)患者血气指标和肺功能的影响。方法:选取本院2015年1月至2018年10月期间收治的210例AECOPD住院患者作为研究对象,随机分为对照组(头孢哌酮钠舒巴坦钠治疗)、持续雾化组(沙丁胺醇、布地奈德持续雾化治疗+头孢哌酮钠舒巴坦钠)、先后雾化组(先给予沙丁胺醇雾化、后给予布地奈德雾化治疗+头孢哌酮钠舒巴坦钠),每组各70例,对比三组的临床疗效、血气指标、肺功能及不良反应。结果:先后雾化组总有效率为91.43%,高于持续雾化组的78.57%及对照组的67.14%(P0.05)。先后雾化组患者治疗5天后氧分压(PaO_2)、氧饱和度(SaO_2)高于持续雾化组及对照组,且持续雾化组高于对照组(P0.05);先后雾化组患者治疗5天后二氧化碳分压(PaCO_2)低于持续雾化组及对照组,且持续雾化组低于对照组(P0.05)。先后雾化组患者第一秒用力呼气容积(FEV_1)、用力肺活量(FVC)、第一秒用力呼吸容积占用力肺活量的百分比(FEV_1/FVC%)、第一秒用力呼气容积占预计值百分比(FEV_1%)高于持续雾化组及对照组,且持续雾化组高于对照组(P0.05)。三组不良反应总发生率比较无统计学差异(P0.05)。结论:沙丁胺醇、布地奈德先后雾化吸入联合头孢哌酮钠舒巴坦钠治疗AECOPD患者疗效确切,可提高患者肺功能,改善血气相关指标。 相似文献
993.
2019年中国植物科学家在国际综合性学术期刊及植物科学主流期刊发表的论文数量大幅增加, 在光生物学、植物抗逆和分子进化等若干领域取得了重要成果。其中, 硅藻光合膜蛋白超分子结构和功能研究入选2019年度中国科学十大进展和中国生命科学十大进展; 植物抗病小体的结构与功能研究入选2019年度中国生命科学十大进展。该文评述了2019年中国科学家在植物科学若干领域取得的重要研究进展, 以期追踪和报道当前中国植物科学领域发展的前沿和热点及展示中国科学家所取得的辉煌成果。 相似文献
994.
Ching‐Long Yeh Chong‐Sheng Leou Tian‐Chuan Hsu Chuan‐Rong Yeh 《Nordic Journal of Botany》2011,29(4):417-419
A new orchid species, Gastrodia sui C. S. Leou, T. C. Hsu & C. L. Yeh is described and illustrated from Taiwan. The new species is closely related to G. callosa J. J. Sm. but distinguishable by the number and position of calli inside the perianth tube, the fused ratio of perianth lobes, and the structure of the lip and column. It is so far only found in the area of Mt Lilung in southern Taiwan. 相似文献
995.
996.
Gyawali S Solis L Chong SL Curtis C Seres P Kornelsen I Thompson R Mushahwar VK 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,110(1):246-255
Deep tissue injury (DTI) is a severe form of pressure ulcer that originates at the bone-muscle interface. It results from mechanical damage and ischemic injury due to unrelieved pressure. Currently, there are no established clinical methods to detect the formation of DTI. Moreover, despite the many recommended methods for preventing pressure ulcers, none so far has significantly reduced the incidence of DTI. The goal of this study was to assess the effectiveness of a new electrical stimulation-based intervention, termed intermittent electrical stimulation (IES), in ameliorating the factors leading to DTI in individuals with compromised mobility and sensation. Specifically, we sought to determine whether IES-induced contractions in the gluteal muscles can 1) reduce pressure in tissue surrounding bony prominences susceptible to the development of DTI and 2) increase oxygenation in deep tissue. Experiments were conducted in individuals with spinal cord injury, and two paradigms of IES were utilized to induce contractions in the gluteus maximus muscles of the seated participants. Changes in surface pressure around the ischial tuberosities were assessed using a pressure-sensing mattress, and changes in deep tissue oxygenation were indirectly assessed using T?*-weighted magnetic resonance imaging (MRI) techniques. Both IES paradigms significantly reduced pressure around the bony prominences in the buttocks by an average of 10-26% (P < 0.05). Furthermore, both IES paradigms induced significant increases in T?* signal intensity (SI), indicating significant increases in tissue oxygenation, which were sustained for the duration of each 10-min trial (P < 0.05). Maximal increases in SI ranged from 2-3.3% (arbitrary units). Direct measurements of oxygenation in adult rats revealed that IES produces up to a 100% increase in tissue oxygenation. The results suggest that IES directly targets factors contributing to the development of DTI in people with reduced mobility and sensation and may therefore be an effective method for the prevention of deep pressure ulcers. 相似文献
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Enterobacter aerogenes is one of the most widely-studied model strains for fermentative hydrogen production. To improve the hydrogen yield of E. aerogenes, the bioengineering on a biomolecular level and metabolic network level is of importance. In this review, the fermentative technology of E. aerogenes for hydrogen production will be first briefly summarized. And then the bioengineering of E. aerogenes for the improvement of hydrogen yield will be thoroughly reviewed, including the anaerobic metabolic networks for hydrogen evolution in E. aerogenes, metabolic engineering for improving hydrogen production in E. aerogenes and mixed culture of E. aerogenes with other hydrogen-producing bacteria to enhance the overall yield in anaerobic cultivation. Finally, a perspective on E. aerogenes as a hydrogen producer including systems bioengineering approach for improving the hydrogen yield and application of the engineered E. aerogenes in mixed culture will be presented. 相似文献