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Research on the Construction Status of the Beijing-Tianjin-Hebei Medical Talent Community and the Countermeasures for Its Realization
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作者 Chao Jing jiaqi zhang 《Proceedings of Business and Economic Studies》 2024年第1期89-93,共5页
In April 2015,the Political Bureau of the CPC Central Committee adopted the“Outline of the Plan for the Coordinated Development of Beijing,Tianjin,and Hebei.”In July 2017,the“Plan for the Integrated Development of ... In April 2015,the Political Bureau of the CPC Central Committee adopted the“Outline of the Plan for the Coordinated Development of Beijing,Tianjin,and Hebei.”In July 2017,the“Plan for the Integrated Development of Beijing,Tianjin,and Hebei Talents(2017–2030),”jointly prepared by the leading groups of the three regions,was officially released.The core of the coordinated development of these three regions is the orderly removal of non-capital functions from Beijing.Talents,especially medical talents,are integral to this transition.The construction of a medical talent community across these three regions promotes the further development of a healthier China,meets the growing needs of the people for a better life,and embodies the concept of putting people first.This paper begins by examining the current situation of the construction of the Beijing-Tianjin-Hebei medical talent community,reviewing the progress made,analyzing existing problems,and proposing targeted countermeasures and suggestions. 展开更多
关键词 Community of medical talents Top level design The party in charge of talents Polarization effect
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Dietary Epimedium extract supplementation improves intestinal functions and alters gut microbiota in broilers 被引量:1
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作者 jiaqi zhang Haitao Yu +4 位作者 Huiyan zhang Qingyu Zhao Wei Si Yuchang Qin Junmin zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1584-1597,共14页
Background Growth-promoting antibiotics have been banned by law in the livestock and poultry breeding industry in many countries.Various alternatives to antibiotics have been investigated for using in livestock.Epimed... Background Growth-promoting antibiotics have been banned by law in the livestock and poultry breeding industry in many countries.Various alternatives to antibiotics have been investigated for using in livestock.Epimedium(EM)is an herb rich in flavonoids that has many beneficial effects on animals.Therefore,this study was planned to explore the potential of EM as a new alternative antibiotic product in animal feed.Methods A total of 7201-day-old male broilers(Arbor Acres Plus)were randomly divided into six groups and fed basal diet(normal control;NC),basal diet supplemented with antibiotic(75 mg/kg chlortetracycline;CTC),and basal diet supplemented with 100,200,400 or 800 mg/kg EM extract for 6 weeks(EM100,EM200,EM400 and EM800 groups).The growth performance at weeks 3 and 6 was measured.Serum,intestinal tissue and feces were collected to assay for antioxidant indexes,intestinal permeability,lactic acid and short-chain fatty acids(SCFAs)profiles,microbial composition,and expression of intestinal barrier genes.Results The average daily feed intake in CTC group at 1-21 d was significantly higher than that in the NC group,and had no statistical difference with EM groups.Compared with NC group,average daily gain in CTC and EM200 groups increased significantly at 1-21 and 1-42 d.Compared with NC group,EM200 and EM400 groups had significantly decreased levels of lipopolysaccharide and D-lactic acid in serum throughout the study.The concentrations of lactic acid,acetic acid,propionic acid,butyric acid and SCFAs in feces of birds fed 200 mg/kg EM diet were significantly higher than those fed chlortetracycline.The dietary supplementation of chlortetracycline and 200 mg/kg EM significantly increased ileal expression of SOD1,Claudin-1 and ZO-1 genes.Dietary supplemented with 200 mg/kg EM increased the relative abundances of g_NK4A214_group and Lactobacillus in the jejunal,while the relative abundances of Microbacterium,Kitasatospora,Bacteroides in the jejunal and Gallibacterium in the ileum decreased.Conclusion Supplementation with 200 mg/kg EM extract improved the composition of intestinal microbiota by regulating the core bacterial genus Lactobacillus,and increased the concentration of beneficial metabolites lactic acid and SCFAs in the flora,thereby improving the antioxidant capacity and intestinal permeability,enhancing the function of tight junction proteins.These beneficial effects improved the growth performance of broilers. 展开更多
关键词 ANTIOXIDATION BROILERS EPIMEDIUM Growth performance MICROBIOTA
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Motor neuron-specific RhoA knockout delays degeneration and promotes regeneration of dendrites in spinal ventral horn after brachial plexus injury
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作者 Mi Li Jiawei Xu +10 位作者 Ying Zou Jialing Lu Aiyue Ou Xinrui Ma jiaqi zhang Yizhou Xu Lanya Fu Jingmin Liu Xianghai Wang Libing Zhou Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2757-2761,共5页
Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be... Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be re-expanded when reinnervation is allowed.RhoA is a target that regulates the cytoskeleton and promotes neuronal survival and axon regeneration.However,the role of RhoA in dendrite degeneration and regeneration is unknown.In this study,we explored the potential role of RhoA in dendrites.A line of motor neuronal conditional knockout mice was developed by crossbreeding HB9~(Cre+)mice with RhoA~(flox/flox)mice.We established two models for assaying dendrite degeneration and regeneration,in which the brachial plexus was transection or crush injured,respectively.We found that at 28 days after brachial plexus transection,the density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice were slightly decreased compared with that in Cre mice.Dendrites underwent degeneration at 7 and 14 days after brachial plexus transection and recovered at 28–56 days.The density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice recovered compared with results in Cre mice.These findings suggest that RhoA knockout in motor neurons attenuates dendrite degeneration and promotes dendrite regeneration after peripheral nerve injury. 展开更多
关键词 brachial plexus conditional knockout DEGENERATION DENDRITES motor neuron peripheral nerve injury REGENERATION RHOA spinal cord ventral horn
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Waste-Derived Catalysts for Water Electrolysis:Circular Economy-Driven Sustainable Green Hydrogen Energy
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作者 Zhijie Chen Sining Yun +7 位作者 Lan Wu jiaqi zhang Xingdong Shi Wei Wei Yiwen Liu Renji Zheng Ning Han Bing-Jie Ni 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第1期43-79,共37页
The sustainable production of green hydrogen via water electrolysis necessitates cost-effective electrocatalysts.By following the circular economy principle,the utilization of waste-derived catalysts significantly pro... The sustainable production of green hydrogen via water electrolysis necessitates cost-effective electrocatalysts.By following the circular economy principle,the utilization of waste-derived catalysts significantly promotes the sustainable development of green hydrogen energy.Currently,diverse waste-derived catalysts have exhibited excellent catalytic performance toward hydrogen evolution reaction(HER),oxygen evolution reaction(OER),and overall water electrolysis(OWE).Herein,we systematically examine recent achievements in waste-derived electrocatalysts for water electrolysis.The general principles of water electrolysis and design principles of efficient electrocatalysts are discussed,followed by the illustration of current strategies for transforming wastes into electrocatalysts.Then,applications of waste-derived catalysts(i.e.,carbon-based catalysts,transitional metal-based catalysts,and carbon-based heterostructure catalysts)in HER,OER,and OWE are reviewed successively.An emphasis is put on correlating the catalysts’structure-performance relationship.Also,challenges and research directions in this booming field are finally highlighted.This review would provide useful insights into the design,synthesis,and applications of waste-derived electrocatalysts,and thus accelerate the development of the circular economy-driven green hydrogen energy scheme. 展开更多
关键词 Waste-derived electrocatalysts Water splitting Sustainable hydrogen energy Catalyst design Circular economy
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A likely autotetraploidization event shaped the Chinese mahogany(Toona sinensis)genome
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作者 Jianyu Wang Ziyi Yang +16 位作者 Tianyu Lei Yan zhang Qimeng Xiao Zijian Yu jiaqi zhang Sangrong Sun Qiang Xu Shaoqi Shen Zimo Yan Mengnan Fang Yue Ding Zihan Liu Qianwen Zhu Ke Ren Yuxin Pan Haibin Liu Jinpeng Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期306-320,共15页
Chinese mahogany(Toona sinensis) is of considerable medical and economic importance, and its genome has been deciphered. However, the process underlying its polyploidy is unclear, and the chromosomal evolutionary traj... Chinese mahogany(Toona sinensis) is of considerable medical and economic importance, and its genome has been deciphered. However, the process underlying its polyploidy is unclear, and the chromosomal evolutionary trajectory is poorly understood. Here, by reanalysing the T.sinensis genome, we found evidence of a tetraploidization event(T. sinensis special tetraploidization, TST) that occurred approximately 15-17 million years ago(MYA) after the core eudicot-common hexaploidization(ECH or gamma) event. We characterized the synonymous nucleotide substitution rates(Ks values) of collinear genes and found that T. sinensis genes affected by the TST evolve at a slower rate than Acer yangbiense genes. Furthermore, we identified homologous genes related to polyploidization and speciation and constructed multiple alignments with different reference genomes. Notably, the significant balance of gene retention and loss characterized in the two TST-derived subgenomes suggests an autopolyploid nature of the TST. Moreover, we deduced the chromosomal karyotypes of the two subgenomes and identified 7chromosomal fusions that have shaped the T. sinensis genome;more information is available on a newly constructed karyotype platform(http://www.cgrpoee.top/Toona_sinensis/index.html). The T. sinensis genome preserves the ancestral chromosome structure of dicotyledons well and could serve as a good reference for understanding genomic changes in other Meliaceae and Sapindales plants. In addition, we verified that tandem duplication and the ECH have promoted the expansion of terpene synthase(TPS) genes;conversely, the TST seems to have inhibited expansion of these genes. This present effort has clarified the polyploidy events of the T. sinensis genome, filled gaps in the history of karyotype evolution, and laid a solid foundation for further genomic studies in the Meliaceae research community and beyond. 展开更多
关键词 Toona sinensis ALIGNMENT Autotetraploidization Karyotype evolution Terpene synthase genes
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A universal charge-compensating strategy for high-energy-density pseudocapacitors
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作者 Baoyi Yin jiaqi zhang +5 位作者 Yuanhui Su Yu Huan Liang Hao Chen Wang Xun Hu Tao Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期333-339,I0010,共8页
For pseudocapacitive electrode materials(PseEMs),despite much progress having been made in achieving both high power density and high energy density,a general strategy to guide the enhancement of intrinsic capacitive ... For pseudocapacitive electrode materials(PseEMs),despite much progress having been made in achieving both high power density and high energy density,a general strategy to guide the enhancement of intrinsic capacitive properties of PseEMs remains lacking.Here,we demonstrate a universal chargecompensating strategy to improve the charge-storage capability of PseEMs intrinsically:ⅰ) in the electrolyte with anion as charge carriers(such as OH-),reducing the multivalent cations of PseEMs into lower valences could create more reversible low-to-high valence redox cou ples to promote the intercalation of the anions;ⅱ) in the electrolytes with cation as charge carriers(such as H^(+),Li^(+),Na^(+)),oxidizing the multivalent cations of PseEMs into higher valences could introduce more reversible high-to-low valence redox couples to promote the intercalation of the cations.And we demonstrated that the improved intrinsic charge-storage capability for PseEMs originates from the increased Faradaic charge storage sites. 展开更多
关键词 Supercapacitors Universal charge-compensating strategy Changed valence state Increased Faradaic charge storage sites
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Exploration and Practice of Postgraduate Training Mode Based on Medical Imaging Information Security
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作者 Yi Ding jiaqi zhang +2 位作者 Zhen Qin Yang Zhao Mingsheng Cao 《计算机教育》 2023年第12期71-77,共7页
In the process of continuous maturity and development of medical imaging diagnosis,it is common to transmit images through public networks.How to ensure the security of transmission,cultivate talents who combine medic... In the process of continuous maturity and development of medical imaging diagnosis,it is common to transmit images through public networks.How to ensure the security of transmission,cultivate talents who combine medical imaging and information security,and explore and cultivate new discipline growth points are difficult problems and challenges for schools and educators.In order to cope with industrial changes,a new round of scientific and technological revolution,and the challenges of the further development of artificial intelligence in medicine,this article will analyze the existing problems in the training of postgraduates in medical imaging information security by combining the actual conditions and characteristics of universities,and put forward countermeasures and suggestions to promote the progress of technology in universities. 展开更多
关键词 Medical imaging Information security Postgraduate training Countermeasures and suggestions
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非小细胞肺癌新辅助免疫治疗进展 被引量:5
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作者 郭超 张家齐 李单青 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第7期524-533,共10页
非小细胞肺癌新辅助免疫治疗发展迅速,包括新辅助单药/双药免疫治疗、新辅助化疗/放疗联合免疫治疗等;部分临床试验结果显示,在经过选择的非小细胞肺癌患者中,新辅助免疫治疗具有可观的病理缓解率并产生可观察到的临床获益,而且毒副作... 非小细胞肺癌新辅助免疫治疗发展迅速,包括新辅助单药/双药免疫治疗、新辅助化疗/放疗联合免疫治疗等;部分临床试验结果显示,在经过选择的非小细胞肺癌患者中,新辅助免疫治疗具有可观的病理缓解率并产生可观察到的临床获益,而且毒副作用可耐受。Nivolumab联合化疗已于近期被美国食品药物监督管理局(Food and Drug Administration,FDA)批准用于非小细胞肺癌新辅助治疗。非小细胞肺癌新辅助免疫治疗的长期疗效、副作用以及手术相关问题需要进一步关注。 展开更多
关键词 肺肿瘤 新辅助治疗 免疫治疗
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Research Progress of Parasite Telomerase and Its Interacting Proteins
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作者 Kaisong Hu jiaqi zhang Jingtong Zheng 《Journal of Biosciences and Medicines》 CAS 2022年第10期221-230,共10页
Telomerase is a nucleoprotein that contains reverse transcriptase activity. It is reversely transcribed into DNA at the end of its chromosome using its own RNA as a template to ensure the length and stability of telom... Telomerase is a nucleoprotein that contains reverse transcriptase activity. It is reversely transcribed into DNA at the end of its chromosome using its own RNA as a template to ensure the length and stability of telomeres. Its physiological function is closely related to the life process of cells. In recent years, the research on telomeres and telomerase has become a new hotspot, people have a more in-depth research and scientific understanding of their structures and functions, and scientists have also attached great importance to the research progress of telomerase increasingly. Researchers in parasite-related research have successively discovered a large number of telomere and telomerase sequences in a variety of different parasites. These achievements have greatly facilitated the scientific research of diseases caused by parasitic infections, providing a solid research basis for the preparation of new drugs, while enriching the treatment protocols of parasitic diseases, and opening new worlds for the prevention of certain diseases and epidemic transmission. This paper reviews the current research progress of telomerase. 展开更多
关键词 TELOMERASE TELOMERES Parasites Research Progress
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微生物胞外多糖及其生物合成途径研究现状 被引量:7
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作者 庞宁 张佳琪 +1 位作者 齐进 姜彬慧 《微生物前沿》 2017年第2期27-34,共8页
微生物胞外多糖因具有独特的物化性质、流变学特性和生物安全性等优势而在工业生产与生活等多个领域具有广泛的应用价值,但是由于生产成本高、产量少等限制其广泛的应用,本文简述了产生胞外多糖的微生物菌种筛选、分离及培养,产糖条件... 微生物胞外多糖因具有独特的物化性质、流变学特性和生物安全性等优势而在工业生产与生活等多个领域具有广泛的应用价值,但是由于生产成本高、产量少等限制其广泛的应用,本文简述了产生胞外多糖的微生物菌种筛选、分离及培养,产糖条件的优化,胞外多糖的提取及分离纯化与微生物胞外多糖的应用等方面的研究进展,重点介绍了微生物胞外多糖代谢途径的研究现状。通过微生物胞外多糖的代谢途径的研究可以获得提高胞外多糖产量的方法,为微生物胞外多糖的工业化应用奠定基础。 展开更多
关键词 微生物胞外多糖 产糖菌 生物合成途径
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结合以旧换新的预售策略
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作者 晏文隽 张嘉琪 +2 位作者 徐嘉宁 何浩楠 王善勇 《中国科学技术大学学报》 CAS CSCD 北大核心 2022年第8期58-68,70,共12页
近来,预售和以旧换新项目在许多行业中越来越受欢迎,现有文献分别研究了这两种策略,但这两个策略相结合的情况还没有被研究过。受商业实践的启示,我们研究了一种新的预售策略(AT策略),该策略利用以旧换新作为参与预售的奖励或折扣。本... 近来,预售和以旧换新项目在许多行业中越来越受欢迎,现有文献分别研究了这两种策略,但这两个策略相结合的情况还没有被研究过。受商业实践的启示,我们研究了一种新的预售策略(AT策略),该策略利用以旧换新作为参与预售的奖励或折扣。本研究分析了在分别采用AT策略、传统预售策略(AS策略)和传统以旧换新策略(TN策略)时卖家的定价决策和最佳利润。我们发现当旧产品的残值足够低且产品成本不是太小时,相对于AT策略,卖家选择AS策略更优。另外,相对于TN策略,当产品残值和产品成本较低时,卖家在大多数情况下应该采用AT策略。此外,我们证明了在AT策略中当产品价格极高时卖家仍旧是有利可图的。即使消费者在预售阶段的效用是负的,他们仍愿意参加预售,因为购买两代产品的总消费者剩余是正的。 展开更多
关键词 预售 以旧换新 产品耐用性 产品残值 策略型消费者
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小细胞肺癌的免疫治疗临床进展 被引量:9
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作者 王维威 张家齐 李单青 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第6期425-433,共9页
小细胞肺癌是一种侵袭性强、预后差的恶性肿瘤,多学科联合的综合治疗是其经典的治疗模式。长期以来,小细胞肺癌的治疗方案一直停滞不前;近些年,免疫治疗药物的初始经验使得小细胞肺癌的治疗出现了新的契机。部分免疫检查点抑制剂的临床... 小细胞肺癌是一种侵袭性强、预后差的恶性肿瘤,多学科联合的综合治疗是其经典的治疗模式。长期以来,小细胞肺癌的治疗方案一直停滞不前;近些年,免疫治疗药物的初始经验使得小细胞肺癌的治疗出现了新的契机。部分免疫检查点抑制剂的临床试验已经证实了其在小细胞肺癌方面的有效性及安全性;基于Ⅲ期临床试验(Impower133和CASPIAN研究)的结果,目前美国国家食品药品监督管理局已经分别批准Atezolizumab、Durvalumab联合化疗用于广泛期小细胞肺癌的一线治疗。包含免疫检查点抑制剂的不同治疗方案在小细胞肺癌人群的临床试验正积极广泛开展,为小细胞肺癌的治疗提供了不同的视野。本文综述目前小细胞肺癌免疫治疗的临床进展。 展开更多
关键词 小细胞肺癌 免疫治疗 临床试验
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粒细胞-巨噬细胞集落刺激因子联合放疗研究进展 被引量:7
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作者 张佳奇 赵路军 +1 位作者 刘宁波 王平 《中国肿瘤临床》 CAS CSCD 北大核心 2018年第9期468-471,共4页
粒细胞-巨噬细胞集落刺激因子(granulocyte-macrophage colony-stimulating factor,GM-CSF)作为一种造血因子可以有效诱导多种具有抑瘤效应的免疫细胞增殖,从而发挥抗肿瘤免疫反应。放疗作为肿瘤治疗的主要手段之一,不仅可以直接杀伤肿... 粒细胞-巨噬细胞集落刺激因子(granulocyte-macrophage colony-stimulating factor,GM-CSF)作为一种造血因子可以有效诱导多种具有抑瘤效应的免疫细胞增殖,从而发挥抗肿瘤免疫反应。放疗作为肿瘤治疗的主要手段之一,不仅可以直接杀伤肿瘤细胞,而且会对抗肿瘤免疫产生影响。多项临床研究提示,放疗联合GM-CSF可以诱导产生旁观者效应并增强对肿瘤的远期控制,从而增强放疗的抗肿瘤效应。本文就GM-CSF及GM-CSF联合放疗的研究进展予以综述。 展开更多
关键词 粒细胞-巨噬细胞集落刺激因子 放射治疗 免疫
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Role of microtubule dynamics in Wallerian degeneration and nerve regeneration after peripheral nerve injury 被引量:1
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作者 Jingmin Liu Lixia Li +14 位作者 Ying Zou Lanya Fu Xinrui Ma Haowen zhang Yizhou Xu Jiawei Xu jiaqi zhang Mi Li Xiaofang Hu Zhenlin Li Xianghai Wang Hao Sun Hui Zheng Lixin Zhu Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第3期673-681,共9页
Wallerian degeneration,the progressive disintegration of distal axons and myelin that occurs after peripheral nerve injury,is essential for creating a permissive microenvironment for nerve regeneration,and involves cy... Wallerian degeneration,the progressive disintegration of distal axons and myelin that occurs after peripheral nerve injury,is essential for creating a permissive microenvironment for nerve regeneration,and involves cytoskeletal reconstruction.However,it is unclear whether microtubule dynamics play a role in this process.To address this,we treated cultured sciatic nerve explants,an in vitro model of Wallerian degeneration,with the microtubule-targeting agents paclitaxel and nocodazole.We found that paclitaxel-induced microtubule stabilization promoted axon and myelin degeneration and Schwann cell dedifferentiation,whereas nocodazole-induced microtubule destabilization inhibited these processes.Evaluation of an in vivo model of peripheral nerve injury showed that treatment with paclitaxel or nocodazole accelerated or attenuated axonal regeneration,as well as functional recovery of nerve conduction and target muscle and motor behavior,respectively.These results suggest that microtubule dynamics participate in peripheral nerve regeneration after injury by affecting Wallerian degeneration.This study was approved by the Animal Care and Use Committee of Southern Medical University,China(approval No.SMUL2015081) on October 15,2015. 展开更多
关键词 AXON DEMYELINATION microtubule dynamics nerve regeneration NOCODAZOLE PACLITAXEL peripheral nerve injury Schwann cell Wallerian degeneration
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哺乳动物早期胚胎发育的体外研究
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作者 王梓川 张嘉祺 李磊 《遗传》 CAS CSCD 北大核心 2022年第4期269-274,共6页
哺乳动物胚胎发育起始于受精卵,受精卵依次形成桑椹胚和囊胚。同时,早期胚胎从输卵管迁入子宫,植入母体子宫后通过原肠运动形成原肠胚并进一步发育为新生个体。哺乳动物体内生命孕育方式造成研究取材和观察等方面的困难,阻碍了人类对哺... 哺乳动物胚胎发育起始于受精卵,受精卵依次形成桑椹胚和囊胚。同时,早期胚胎从输卵管迁入子宫,植入母体子宫后通过原肠运动形成原肠胚并进一步发育为新生个体。哺乳动物体内生命孕育方式造成研究取材和观察等方面的困难,阻碍了人类对哺乳动物胚胎发育过程的认识。因此,必需开发哺乳动物体外胚胎技术,以克服体内发育方式所带来的研究困难。2021年12月,Sicence杂志公布了2021年十大科学突破,“体外胚胎为人类早期发育研究开辟新的方向”位列其中。本文对哺乳动物体外胚胎的研究历史和最新进展进行评述,同时探讨这些新技术在相关领域研究中的应用,以期为人类早期胚胎发育和相关疾病研究带来启示。 展开更多
关键词 早期胚胎发育 胚胎体外培养 人早期胚胎样结构 类囊胚
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基于转动光谱研究异硫氰酸乙氧羰基酯的分子结构和构象平衡
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作者 徐玉高 李炆芹 +1 位作者 张家齐 冯刚 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第6期875-882,I0011-I0038,I0072,共37页
本文利用超声射流-傅里叶变换微波波谱技术对异硫氰酸乙氧羰基酯的转动光谱进行了研究.实验测定了异硫氰酸乙氧羰基酯的两个构象的转动光谱,即构象TCC(C-C-O-C、C-O-C=O、O-C(=O)-NCS骨架分别为反式、顺式、顺式朝向)和构象GCC(C-CO-C、... 本文利用超声射流-傅里叶变换微波波谱技术对异硫氰酸乙氧羰基酯的转动光谱进行了研究.实验测定了异硫氰酸乙氧羰基酯的两个构象的转动光谱,即构象TCC(C-C-O-C、C-O-C=O、O-C(=O)-NCS骨架分别为反式、顺式、顺式朝向)和构象GCC(C-CO-C、C-O-C=O、O-C(=O)-NCS骨架分别为交叉式、顺式、顺式朝向).此外,在自然丰度下测定了这两个构象的13C、15N和34S的单取代同位素异构体的转动光谱,获得了精确的转动常数和14N核四极耦合常数的数值.基于实验测定的转动常数计算得到了异硫氰酸乙氧羰基酯的分子结构参数.对于构象TCC,同位素取代未改变其Pcc值,表明该构象具有Cs对称性,即重原子位于分子的ab平面上. 展开更多
关键词 微波光谱 量子化学理论计算结果 结构分析 超声射流
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Phylogeny and Biogeography of Common Toad(Bufo bufo) in Xinjiang, China
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作者 Siqi WANG Chunxia XU +4 位作者 jiaqi zhang Supen WANG Xuan LIU Xuejiao YANG Yiming LI 《Asian Herpetological Research》 SCIE CSCD 2021年第2期201-212,共12页
The common toad, Bufo bufo(Linnaeus, 1758), is widely distributed in Europe and parts of Africa. Previous studies of the genetic relationships among B. bufo populations have not included Asian populations. Here, we in... The common toad, Bufo bufo(Linnaeus, 1758), is widely distributed in Europe and parts of Africa. Previous studies of the genetic relationships among B. bufo populations have not included Asian populations. Here, we investigated the phylogenetic relationships of B. bufo, including a population from Xinjiang, China, using 722 bp of the mitochondrial cytochrome b sequence and identified six subclades and 85 haplotypes in populations from 22 countries. Phylogenetic analyses and pedigree differentiation revealed that the subclade containing the Xinjiang population has undergone a relatively recent expansion. Combining our results with those of previous studies, we found that the common toad population of Xinjiang, China, belongs to the European-Caucasian lineage and that its closest relatives based on phylogenetic relationships were eastern European populations. Our research contributes to expanding knowledge of the geographic distribution of B. bufo and illuminates the lineage and genetic relationships of the B. bu fo population in Xinjiang, China. Future research should continue to update the geographic distribution of B. bufo and complete a genetic investigation of the full range of this species. 展开更多
关键词 distribution genetic distance genetic structure HAPLOTYPE mitochondrial DNA phylogenetic tree
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Valproic acid enhances neurosphere formation in cultured rat embryonic cortical cells through TGFβ1 signaling
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作者 Cui Qi jiaqi zhang +3 位作者 Yuanyuan Wang Mingyan Lin Jun Gao Haiying Lu 《The Journal of Biomedical Research》 CAS CSCD 2022年第2期127-140,共14页
This study aimed to investigate the effect and mechanism of valproic acid(VPA)on the neurosphere formation in rat embryonic cortical cells.We used free-floating neurosphere formation as a model system to evaluate the ... This study aimed to investigate the effect and mechanism of valproic acid(VPA)on the neurosphere formation in rat embryonic cortical cells.We used free-floating neurosphere formation as a model system to evaluate the VPA on the proliferation of neural stem cells(NSCs).We found a time-and dose-dependent increase in neurosphere formation and NSC proliferation after VPA treatment.Further RNA-seq analysis demonstrated that the upregulated TGFβ1 signaling might attribute to the effect of VPA on the neurosphere formation and NSC proliferation.Consistently,the neurosphere formation and NSC proliferation were blocked by the treatment with SB431542,an inhibitor of TGFβ1 receptor.Moreover,in a coculture system,NSCs treated with VPA significantly reduced the oxygen-glucose deprivation-induced neuronal apoptosis.Taken together,our results showed that VPA could enhance neurosphere formation and NSC proliferation by activating TGFβ1,which might be a novel therapeutic strategy for neurological disorders. 展开更多
关键词 valproic acid neural stem cells neurosphere formation PROLIFERATION transforming growth factorβ1
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Application of eDNA Metabarcoding for Detecting Anura in North China
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作者 Wenhao LI Mingshuo QIN +10 位作者 Xianglei HOU jiaqi zhang Siqi WANG Yu LI Zexu LUO Teng DENG Tianjian SONG Chunxia XU Xuan LIU Xuyu WANG Yiming LI 《Asian Herpetological Research》 SCIE CSCD 2022年第4期224-231,共8页
eDNA metabarcoding is an advanced method formonitoring biodiversityproposed in recent years.By analyzing DNA in water,soil and sediment samples,the technology obtains species distribution and population quantity infor... eDNA metabarcoding is an advanced method formonitoring biodiversityproposed in recent years.By analyzing DNA in water,soil and sediment samples,the technology obtains species distribution and population quantity information.It was found that macrobarcode technology is more accurate than the traditional method in measuring the species richness of some groups.In Europe,America and South America,the relia bility of this technology in monitoring amphibian diversity in the wild was studied,and it was found to be better than traditional biodiversity monitoring methods in detecting species diversity.At present,amphibian monitoring mainly depends on various traditional methods,such as transects,drift fence traps,artificial shelters and mark-recapture.These monitoring techniques have many shortcomings,such as low accuracy and strong subjectivity of study results.These technologies have poor effects on rare,invasive and endangered species with strong concealment ability,low density and strong seasonality and are difficult to implement in sites inaccessible to people.Traditional monitoring technology also requires considerable investment of human and material resources,and the economic cost is relatively high,while eDNA metabarcoding ismore efficient and less costly,so it is important to use eDNA meta barcoding in amphibian monitoring in China.In this study,the eDNA meta barcoding and traditional line transect method(TLTM)were used to study the characteristics of the two methods in the Beijing-Tianjin-Hebeiregion.Repeated samplingwas conducted on 58 waterbodies in July 2019 and June 2020.After sequencing the samples using highthroughput sequencing technology,the differences between metabarcoding and commonly used TLTM surveys in detecting the diversity of four amphibians in North China were assessed.Our results showed that eDNA meta barcoding is more sensitive to the detection of the four amphibian species in the sampling area,and the combined use of eDNA metabarcoding and TLTM can improve the survey results of amphibians in the survey area to the greatest extent.In addition,in the process of species classification and identification of metabarcoding results,7 species of reptiles were detected,indicating that eDNA metabarcoding is also useful to detect reptiles.The results of this study indicate that metabarcoding in combination with TLTM can accurately estimate the diversityof amphibians in a short-term survey in North China and is also useful in reptile species detection. 展开更多
关键词 ANURA BIODIVERSITY EDNA metabarcoding
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Multi-Mode Guided Waves Based Reference-Free Damage Diagnostic Imaging in Plates
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作者 jiaqi zhang Kehai Liu +3 位作者 Chang Gao Zhanjun Wu Yuebin Zheng Dongyue Gao 《Structural Durability & Health Monitoring》 EI 2019年第1期41-59,共19页
Probability-based diagnostic imaging(PDI)is one of the most well-known damage identification methods using guided waves.It is usually applied to diagnose damage in plates.The previous studies were dependent on the cer... Probability-based diagnostic imaging(PDI)is one of the most well-known damage identification methods using guided waves.It is usually applied to diagnose damage in plates.The previous studies were dependent on the certain damage index(DI)which is always calculated from the guided wave signals.In conventional methods,DI is simply defined by comparing the real-time data with the baseline data as reference.However,the baseline signal is easily affected by varying environmental conditions of structures.In this paper,a reference-free diagnostic imaging method is developed to avoid the influence of environmental factors,such as temperature and load conditions.The DI is defined based on the mode conversion of multi-mode guided waves with realtime signals without baseline signals.To improve the accuracy of diagnosis,two terms are included in the reference-free DI.One is called energy DI,which is defined based on the feature of signal energy.The other is called correlation DI and is defined based on the correlation coefficient.Then the PDI algorithm can be carried out instantaneously according to the reference-free DI.The real-time signals which are used to calculate DI are collected by the piezoelectric lead zirconate titanate(PZT)transducers placed on both sides of a plate.The numerical simulations by the finite element(FE)method on aluminum plates with PZT arrays are performed to validate the effectiveness of the reference-free damage diagnostic imaging.The approach is validated by two different arrays:a circle network and a square network.The results of diagnostic imaging are demonstrated and discussed in this paper.Furthermore,the advantage of reference-free DI is investigated by comparing the accuracy of defined reference-free DI and energy DI. 展开更多
关键词 Multi-mode guided waves probability-based diagnostic imaging referencefree mode conversion
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