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肠道菌群与天然产物的相互作用研究进展

中国医药生物技术 2024年第1期19卷 52-56页

作者：丁劲文林媛蒋建东中国医学科学院北京协和医学院药物研究所天然药物活性物质与功能国家重点实验室北京100050

大量研究表明天然产物对肠道菌群具有多种生物活性,可能影响肠道菌群组成、菌群代谢物含量及肠道黏膜屏障完整性等,同时肠道菌群产生的多种酶又能影响天然产物活性成分的生物利用度以及药理毒理活性。两者相互作用对宿主的健康和疾病治... 详细信息

大量研究表明天然产物对肠道菌群具有多种生物活性,可能影响肠道菌群组成、菌群代谢物含量及肠道黏膜屏障完整性等,同时肠道菌群产生的多种酶又能影响天然产物活性成分的生物利用度以及药理毒理活性。两者相互作用对宿主的健康和疾病治疗至关重要。本文按照天然产物活性成分的结构类型归纳了天然产物与肠道菌群的相互作用的分子机制,为进一步研究天然产物如何通过调控肠道菌群进而发挥治疗疾病的作用提供参考依据。

关键词：肠道菌群天然产物相互作用分子机制

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甲状旁腺术中识别技术及临床应用和研究现况

西安交通大学学报（医学版） 2024年第1期45卷 49-54页

作者：贺晨宇姜可伟北京大学人民医院胃肠外科北京100442 北京大学人民医院外科肿瘤研究室、结直肠癌诊疗研究北京市重点实验室北京100442

甲状旁腺在机体钙磷代谢中有重要作用,颈部手术中完整保留甲状旁腺对避免术后甲状旁腺功能减退和术后低钙血症至关重要。目前大多数甲状腺手术中仍依赖传统肉眼识别方式或通过术中冰冻辨认甲状旁腺,前者依赖于术者经验,后者所消耗的时... 详细信息

甲状旁腺在机体钙磷代谢中有重要作用,颈部手术中完整保留甲状旁腺对避免术后甲状旁腺功能减退和术后低钙血症至关重要。目前大多数甲状腺手术中仍依赖传统肉眼识别方式或通过术中冰冻辨认甲状旁腺,前者依赖于术者经验,后者所消耗的时间和费用较高。近年,国内外学者对术中有助于识别甲状旁腺的染色技术和基于荧光的成像技术进行了相关研究,如亚甲蓝、纳米炭、近红外自体荧光、吲哚菁绿血管造影技术、激光散斑对比成像等,均可显著提高对甲状旁腺的识别与保护。本文将对甲状旁腺术中识别技术的临床研究进展情况作一综述。

关键词：甲状腺癌根治术甲状旁腺保护术中识别

Development of a Tactile and Slip Sensor with a Biomimetic Structure-enhanced Sensing Mechanism

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Journal of Bionic Engineering 2019年第1期16卷 47-55页

作者： Yonggang jiang Zhiqiang Ma Bonan Cao Longlong Gong lin Feng Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 100191China

Tactile and slip sensors have gained tremendous attention for their promising applications in the fields of smart robotics,implantable medical devices and minimally invasive *** by the structure-enhanced sensing mechanisms of human fingertips and tree frog toes,we developed a tactile and slip sensor by combining biomimetic surface microstructures with highly sensitive P(VDF-TrFE)nanofiber sensors on a flexible polyimide *** the surface microstructures could mediate the micro-vibration induced by slip motion,the frequencies of output signals revealed a strong correlation with the periods of *** addition,we proposed a method to discriminate touch force from slip motion using the criterion of standard deviation of time delay from the output signals of neighboring sensor elements.

关键词： tactile sensor slip detection nanofiber microstructure biomimetic sensing

Precoding with interference suppression sequence scheme for OFDM-based cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 59-64页

作者： ZHAO Cheng-lin ZHANG Kun SUN Xue-bin jiang Ting Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Orthogonal frequency division multiplexing （OFDM） is considered to be one of the promising schemes for cognitive radios （CR） systems, due to its flexibility in spectrum shaping. However, the traditional way of spectrum-notching failed to suppress out-of-band leakage enough, resulting in interference with licensed users （LUs）. A novel spectrum shaping scheme is proposed in this article, where a precoder with interference suppression sequence （ISS） is for the first time introduced for shaping the spectrum of OFDM signals in OFDM-based CR systems. The precoder matrix together with ISS matrix is obtained by minimizing the power of out-of-band interference, which results in the sufficient interference suppression of OFDM signal to LUs Analysis and simulation results show that the proposed scheme can significantly suppress the interference power to LUs at a little cost of precoding efficiency. Meanwhile, the peak-to-average-power-ratio （PAPR） is invariable and the bit-error-rate （BER） performance over Rayleigh fading channel is improved.

关键词： OFDM cognitive radio precoding spectrum shaping

Mild hypothermia combined with neural stem cell transplantation for hypoxic-ischemic encephalopathy: neuroprotective effects of combined therapy

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Neural Regeneration Research 2014年第19期9卷 1745-1752页

作者： lin Wang Feng jiang Qifeng Li Xiaoguang He Jie Ma Department of Pediatric Neurosurgery Xinhua Hospital of Shanghai Jiaotong University

Neural stem cell transplantation is a useful treatment for ischemic stroke, but apoptosis often occurs in the hypoxic-ischemic environment of the brain after cell transplantation. In this study, we determined if mild hypothermia （27-28~C） can increase the survival rate of neural stem cells （1.0 x 105/~tL） transplanted into neonatal mice with hypoxic-ischemic encephalopathy. Long-term effects on neurological functioning of the mice were also examined. After mild hy- pothermia combined with neural stem cell transplantation, we observed decreased expression levels of inflammatory factor nuclear factor-kappa B and apoptotic factor caspase-3, reduced cerebral infarct volumes, increased survival rate of transplanted cells, and marked improvements in neurological function. Thus, the neuroprotective effects of mild hypothermia combined with neural stem cell transplantation are superior to those of monotherapy. Moreover, our findings suggest that the neuroprotective effects of mild hypothermia combined with neural stem cell transplantation on hypoxic-ischemic encephalopathy are achieved by anti-inflammatory and an- ti-apoptotic mechanisms.

关键词： nerve regeneration brain injury hypoxic-ischemic encephalopathy neural precursorcells hypothermia neural stem cells cell transplantation hippocampus neuron cell apoptosis astrocytes oligodendrotytes neuroprotection NSFC grants neural regeneration

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超支化聚羟基酯的非常规荧光发射行为

塑料工业 2024年第4期52卷 51-55页

作者：薛小强刘志坤黄文艳杨宏军江力蒋其民蒋必彪常州大学材料科学与工程学院江苏常州213164 常州工学院化工与材料学院碳纤维新材料产业学院江苏常州213032

以丙三醇三缩水甘油醚(GTE)、丁二酸(SA)、顺丁烯二酸(MA)为原料,通过羧基与环氧结构在无催化剂条件下开环聚合制备一类具有非常规荧光发射行为的超支化聚羟基酯(PHE)。使用傅里叶变换红外光谱(FTIR)、核磁共振氢谱(~1H NMR)和凝胶渗透... 详细信息

以丙三醇三缩水甘油醚(GTE)、丁二酸(SA)、顺丁烯二酸(MA)为原料,通过羧基与环氧结构在无催化剂条件下开环聚合制备一类具有非常规荧光发射行为的超支化聚羟基酯(PHE)。使用傅里叶变换红外光谱(FTIR)、核磁共振氢谱(~1H NMR)和凝胶渗透色谱(GPC)对聚合物的结构进行表征。使用紫外-可见分光光度计(UV-Vis)和荧光分光光度计等手段对其荧光性能进行探究。结果显示,PHE表现出稳定的发光性能,随着聚合物溶液浓度的增加,其簇聚诱导发光效率获得显著增强,具有浓度增强发射及激发波长依赖性等非常规发光的典型特性,为设计非传统发光材料提供了新的思路。

关键词：非常规发光聚羟基酯簇聚诱导发光

盆腔炎治疗仪结合低频神经肌肉电刺激对薄型子宫内膜不孕症患者子宫内膜容受性及妊娠结局的影响

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中国性科学 2024年第3期33卷 78-82页

作者：江秋林忠覃晓玲张宾广西壮族自治区生殖医院妇科南宁530000

目的探讨盆腔炎治疗仪结合低频神经肌肉电刺激对薄型子宫内膜不孕症患者子宫内膜容受性及妊娠结局的影响。方法选取2020年1月至2021年6月广西壮族自治区生殖医院收治的96例薄型子宫内膜不孕症患者作为研究对象,采用随机数字表法分为对... 详细信息

目的探讨盆腔炎治疗仪结合低频神经肌肉电刺激对薄型子宫内膜不孕症患者子宫内膜容受性及妊娠结局的影响。方法选取2020年1月至2021年6月广西壮族自治区生殖医院收治的96例薄型子宫内膜不孕症患者作为研究对象,采用随机数字表法分为对照组和观察组,各48例。对照组予以低频电刺激治疗,观察组予以盆腔炎治疗仪结合低频电刺激治疗。治疗后,测定两组子宫内膜厚度、子宫内膜容积、子宫内膜形态分型以及血流分型和血流动力学参数,统计两组治疗后12个月内妊娠成功率。结果观察组治疗后子宫内膜厚度、子宫内膜容积较对照组大(P<0.05);子宫内膜形态分型中A型患者所占比例较高,B型及C型患者所占比例较低(P<0.05);子宫内膜血流分型中Ⅲ型患者所占比例较高,Ⅰ型及Ⅱ患者所占比例较低(P<0.05);子宫内膜血流搏动指数(PI)、阻力指数(RI)、收缩期峰值流速/舒张末期流速(S/D)较低(P<0.05)。治疗后12个月内,观察组妊娠成功率高于对照组(81.25%vs.62.50%,P<0.05)。观察组平均妊娠时间较对照组明显缩短(P<0.05)。结论盆腔炎治疗仪结合低频神经肌肉电刺激有利于改善薄型子宫内膜不孕症患者子宫内膜厚度、形态及血流动力学参数,提高妊娠成功率。

关键词：不孕症薄型子宫内膜盆腔炎治疗仪低频神经肌肉电刺激子宫内膜容受性妊娠结局

Residual-stress relaxation mechanism and model description of 5052H32 Al alloy spun ellipsoidal heads during annealing treatment

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Advances in Manufacturing 2022年第1期10卷 87-100页

作者： Yong-Cheng lin jiang-Shan Zhu Jia-Yang Chen Jun-Quan Wang School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083People’s Republic of China

Marginal-restraint mandrel-free spinning is an advanced technology for manufacturing ellipsoidal heads with large diameter-thickness ***,the spinning-induced residual stress,which greatly influences the in-service performance of spun heads,should be *** this study,the effects of annealing on the residual-stress relaxation behavior of 5052H32 aluminum alloy spun heads were *** is found that the residual stress first rapidly decreases and then remains steady with the increase in annealing time at the tested annealing *** relaxation of the residual stress becomes increasingly obvious with the increase in annealing *** the annealing temperature is less than 220℃,there are no obvious changes in grain ***,the spinning-induced dislocations are consumed by the static recovery behavior,which decreases the residual stress during *** the annealing temperature is approximately 300℃,the broken grains transform into equiaxed *** addition,static recrystallization and recovery behaviors occur simultaneously to promote the relaxation of the residual *** the different stress relaxation mechanisms,a model based on the Zener-Wert-Avrami equation was established to predict the residual-stress relaxation ***,the optimized annealing temperature and time were approximately 300C and 30 min,respectively.

关键词： Spinning Residual stress Annealing treatment Microstructure evolution Relaxation mechanism

Data-driven Two-step Day-ahead Electricity Price Forecasting Considering Price Spikes

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Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 523-533页

作者： Shengyuan Liu Yicheng jiang Zhenzhi lin Fushuan Wen Yi Ding Li Yang School of Electrical Engineering Zhejiang UniversityHangzhou 310027China School of Electrical Engineering Shandong UniversityJinan 250061China State Grid Zhejiang Electric Power Corporation Hangzhou 310007ChinaHangzhou 310027China

In the electricity market environment,electricity price forecasting plays an essential role in the decision-making process of a power generation company,especially in developing the optimal bidding strategy for maximizing ***,it is necessary for a power generation company to develop an accurate electricity price forecasting *** this background,this paper proposes a two-step day-ahead electricity price forecasting algorithm based on the weighted Knearest neighborhood(WKNN)method and the Gaussian process regression(GPR)*** the first step,several predictors,i.e.,operation indicators,are presented and the WKNN method is employed to detect the day-ahead price spike based on these *** the second step,the outputs of the first step are regarded as a new predictor,and it is utilized together with the operation indicators to accurately forecast the electricity price based on the GPR *** proposed algorithm is verified by actual market data in Pennsylvania-New JerseyMaryland Interconnection(PJM),and comparisons between this algorithm and existing ones are also made to demonstrate the effectiveness of the proposed *** results show that the proposed algorithm can attain accurate price forecasting results even with several price spikes in historical electricity price data.

关键词： Electricity market electricity price forecasting price spike weighted K-nearest neighborhood(WKNN) Gaussian process regression(GPR).