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道地药材天麻DNA真伪鉴定试剂盒的研制与评价

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中国现代应用药学 2024年第9期41卷 1198-1203页

作者：马秋贺马玉贺刘悦李涛高丽君夏薇李明成曲永梅北华大学医学技术学院吉林132013 吉林省中药DNA指纹检测技术科技创新中心吉林132013 吉林国安药业有限公司吉林132013

目的建立一种将DNA提取技术与PCR技术相结合的天麻DNA真伪鉴定试剂盒,并对试剂盒性能进行方法学评价。方法通过美国国家生物技术信息中心(NCBI)查找天麻及其常见伪品紫茉莉根、大丽菊块茎、马铃薯的ITS2序列,应用DNAMAN进行多序列比对,N... 详细信息

目的建立一种将DNA提取技术与PCR技术相结合的天麻DNA真伪鉴定试剂盒,并对试剂盒性能进行方法学评价。方法通过美国国家生物技术信息中心(NCBI)查找天麻及其常见伪品紫茉莉根、大丽菊块茎、马铃薯的ITS2序列,应用DNAMAN进行多序列比对,NCBI-Primer-Blast设计天麻特异性引物。改良植物常用DNA提取的CTAB法,确保提取出高效的正品天麻及其常见伪品的基因组DNA,应用紫外分光光度法测其浓度及纯度。优化PCR反应体系,确定试剂盒的组成与反应条件,随机抽样检测市售天麻样品。结果应用所研制的试剂盒提取样品DNA,纯度OD260/OD280值为(1.87±0.13),灵敏度为10 ng·μL^(-1),3次重复性检测结果相同,反复冻融5、10、15、20次对检测效果无影响,于-20℃可保存1年,检测10个市售天麻样品,其中7个是正品,3个是伪品。结论道地药材天麻DNA真伪鉴定试剂盒特异性强,灵敏度高,重复性和稳定性均良好,检测结果准确,适用于天麻及其常见伪品的快速鉴别。

关键词：天麻 ITS2 DNA提取真伪鉴定试剂盒聚合酶链式反应

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深度学习在乳腺癌影像学检查中的应用进展

计算机科学与探索 2024年第2期18卷 301-319页

作者：王一凡刘静马金刚邵润华陈天真李明山东中医药大学智能与信息工程学院济南250355 山东浪潮优派科技教育有限公司济南250101

乳腺癌是女性最常见的恶性肿瘤,其早期发现具有决定性意义。乳腺影像学检查在早期发现乳腺癌以及在治疗期间监测与评估方面发挥着重要作用,但人工检测医学影像通常耗时耗力。最近,深度学习算法在早期乳腺癌诊断工作中取得了显著进展。... 详细信息

乳腺癌是女性最常见的恶性肿瘤,其早期发现具有决定性意义。乳腺影像学检查在早期发现乳腺癌以及在治疗期间监测与评估方面发挥着重要作用,但人工检测医学影像通常耗时耗力。最近,深度学习算法在早期乳腺癌诊断工作中取得了显著进展。通过梳理近几年的相关文献,对深度学习技术在不同成像模式的乳腺癌诊断中的应用进行了系统综述,旨在为深入开展基于深度学习的乳腺癌诊断研究提供参考。首先概述了乳腺X线摄影、超声影像、磁共振成像和正电子发射计算机断层显像四种乳腺癌成像模式并进行了简要对比,列举了多种成像方式对应的公共数据集。重点对基于上述四种不同成像模式的深度学习架构的不同任务(病变检测、分割和分类)进行了系统的综述,对比分析了各算法性能、改进思路及其优缺点。最后,对现有技术存在的问题进行分析,并针对目前工作的局限性对未来发展方向进行展望。

关键词：乳腺癌深度学习计算机辅助诊断影像学检查

HEMODYNAMICS FOR ASYMMETRIC INLET AxiaL VELOCITY PROFILE IN CAROTID BIFURCATION MODEL

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Journal of Hydrodynamics 2008年第5期20卷 656-661页

作者： DING Zu-rong liu Bin YANG Shuo xia Yan Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

The asymmetric inlet velocity profile has been observed in phantom model using LDA and in health subjects using Magnet Resonance （MR）. The effects of asymmetric inlet axial velocity profile on the flow field and the Wall Shear Stress （WSS） of carotid bifurcation were numerically studied herein with the TF-AHCB model, The results show that the Wall Shear Stress Gradient （WSSG） in the front part of the sinus for inward-tilting inlet axial velocity profile is nearly 2 times of that for the symmetric one in the beginning of systole, the end of systole, and diastole, respectively. The area of WSS below 5× 10^-3 Pa at the outer wall of the sinus for outward-tilting inlet axial velocity profile is 1.5 times of that for the inward-tilting one during diastole of the cardiac cycle. The asymmetric inlet velocity profiles can reduce the flow velocity near the inner wall of the sinus, which has been normally considered a high velocity region. It is concluded that besides bifurcation geometry and flow waveform, the asymmetry of inlet velocity profile is probably a factor influencing atherosclerosis.

关键词： carotid bifurcation numerical simulation inlet velocity profile Wall Shear Stress(WSS) Wall Shear Stress Gradient(WSSG)

黄河小浪底水库地表水中重金属的时空变化与概率健康风险

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环境科学 2024年第4期45卷 2054-2066页

作者：王亮邓雪娇王潇磊李明刘奕尧娄亚敏涂响张坤锋河南省济源生态环境监测中心济源459000 中国环境监测总站北京100012 河南省生态环境监测和安全中心郑州450046 中国环境科学研究院北京100012

小浪底水库地表水重金属污染是我国黄河流域水安全的一个重要问题.2014~2022年期间,调查了6种重金属(Cu、Zn、Pb、As、Hg和Cd)的时空分布并采用重金属污染指数、内梅罗指数和污染程度对其污染水平进行评价.结果表明,重金属污染水平较低(... 详细信息

小浪底水库地表水重金属污染是我国黄河流域水安全的一个重要问题.2014~2022年期间,调查了6种重金属(Cu、Zn、Pb、As、Hg和Cd)的时空分布并采用重金属污染指数、内梅罗指数和污染程度对其污染水平进行评价.结果表明,重金属污染水平较低(HPI平均值为18.15),符合地表水Ⅲ类水质阈值.6种重金属检出率为91.6%~92.9%,浓度中值范围为0.020(Hg)~1.850(As)μg·L^(-1).呈现出丰水期浓度低于平枯水期,下游断面浓度较高,且在过去的9 a呈现下降趋势的时空特征.重金属污染主要来源于工农业生产和人为排放.此外,结果发现TN、高锰酸盐指数和NH_(4)^(+)-N与重金属浓度有很强的相关性(P<0.05),这表明水中重金属的迁移、转化和吸附沉降可能受到相关因素的影响.敏感性分析表明,金属浓度(贡献率为56.56%~92.27%)是重金属健康风险评估的主要影响因素.此外,虽然重金属暴露不会对人体造成不良影响,但在极端条件下实际风险可能较高.总之,研究对公共健康和环境管理都有潜在的应用价值.

关键词：小浪底水库表层水体重金属年际变化营养盐概率风险

Triggering star formation by both radiative and mechanical AGN feedback

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Research in Astronomy and Astrophysics 2013年第8期13卷 899-911页

作者： Chao liu Zhao-ming Gan Fu-Guo Xie Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences

We perform two dimensional hydrodynamic numerical simulations to study the positive active galactic nucleus （AGN） feedback which triggers, rather than suppresses, star formation. Recently, it was shown by Nayakshin et al. and Ishibashi et al. that star formation occurs when the cold interstellar medium （ISM） is squeezed by the impact of mass outflow or radiation pressure, respectively. Mass outflow is ubiquitous in this astrophysical context, and radiation pressure is also important if the AGN is luminous. For the first time in this subject, we incorporate both mass outflow feedback and radiative feedback into our model. Consequently, the ISM is shocked into shells by the AGN feedback, and these shells soon fragment into clumps and filaments because of Rayleigh-Taylor and thermal instabilities. We have two major findings：（1） the star formation rate can indeed be very large in the clumps and filaments. However, the resultant star formation rate density is too large compared with previous works, which is mainly because we ignore the fact that most of the stars that are formed would be disrupted when they move away from the galactic center. （2） Although radiation pressure feedback has a limited effect, when mass outflow feedback is also included, they reinforce each other. Specifically, in the gas-poor case, mass outflow is always the dominant contributor to feedback.

关键词： methods: numerical - accretion - shock waves - galaxies: active - galaxies: starburst

复杂海洋环境水下航行体低频声传播损失计算方法综述

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舰船科学技术 2024年第3期46卷 13-18页

作者：纪兴刘力溟计方李国楠鹿绍庆中国船舶集团有限公司上海200011 中国舰船研究院北京100101

本文对国内外水下航行体低频声学特征传播损失计算的传统方法和改进方法进行综述,并针对复杂海洋边界条件、三维海洋环境等问题的传播损失仿真计算的适用性进行分析,提炼并总结了复杂海洋环境下传播损失计算方法的研究现状。未来,水下... 详细信息

本文对国内外水下航行体低频声学特征传播损失计算的传统方法和改进方法进行综述,并针对复杂海洋边界条件、三维海洋环境等问题的传播损失仿真计算的适用性进行分析,提炼并总结了复杂海洋环境下传播损失计算方法的研究现状。未来,水下航行体声传播损失研究将更加聚焦于低频声传播特性、声场时-空-频相干特性以及两极冰区环境下的声传播规律等问题,进一步提高传播损失计算方法在复杂海洋环境下的准确性和稳定性是重点研究方向。

关键词：传播损失三维海洋环境复杂海底地形边界条件

Electroacupuncture improves learning and memory functions in a rat cerebral ischemia/reperfusion injury model through PI3K/Akt signaling pathway activation

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Neural Regeneration Research 2021年第6期16卷 1011-1016页

作者： Hui-Ling Wang Fei-Lai liu Rui-Qing Li ming-Yue Wan Jie-Ying Li Jing Shi ming-Li Wu Jun-Hua Chen Wei-Juan Sun Hong-xia Feng Wei Zhao Jin Huang Ren-Chao liu Wen-Xue Hao xiao-Dong Feng Rehabilitation Center the First Affiliated Hospital of Henan University of Traditional Chinese MedicineZhengzhouHenan ProvinceChina Department of Rehabilitation Medicine Fujian University of Chinese MedicineFuzhouFujian ProvinceChina Department of Rehabilitation Medicine Henan University of Chinese MedicineZhengzhouHenan ProvinceChina

Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia,but the underlying mechanism has not yet been fully *** have shown that autophagy plays an important role in the formation and development of cognitive impairment,and the phosphoinositide 3-kinase(PI3K)/Akt signaling pathway plays an important role in autophagy *** investigate the role played by the PI3K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models,we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture *** at 2 hours after modeling,electroacupuncture was delivered at the Shenting(GV24)and Baihui(GV20)acupoints,with a dilatational wave(1-20 Hz frequency,2 mA intensity,6 V peak voltage),for 30 minutes/day over 8 consecutive *** results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury,increased the mRNA expression levels of the PI3K/Akt signaling pathwayrelated factors Beclin-1,mammalian target of rapamycin(mTOR),and PI3K,increased the protein expression levels of phosphorylated Akt,Beclin-1,PI3K,and mTOR in the ischemic cerebral cortex,and simultaneously reduced p53 mRNA and protein expression *** the Morris water maze test,the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture *** the spatial probe test,the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture *** stimulation applied to the Shenting(GV24)and Baihui(GV20)acupoints activated the PI3K/Akt signaling pathway and improved rat learning and memory *** study was approved by the Animal Ethics Committee

关键词： acupuncture brain central nervous system factor neurological function pathways protein stroke

高等职业教育“五位一体”组团式援疆模式研究——以河南援助哈密职业技术学院为例

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黑龙江教育（高教研究与评估） 2024年第1期 17-19页

作者：王庆丰范莹莹尤明霞中原工学院河南郑州450007 哈密职业技术学院新疆哈密839001

围绕培育受援高职院校内生发展动力的核心目标,河南省创新性地打造“办学理念+教师发展+科研帮带+学生培养+校园文化”的五位一体高等职业教育组团式援疆模式,以办学理念为指引,以教师发展为抓手,以科研帮带为手段,以学生培养为根本,以... 详细信息

围绕培育受援高职院校内生发展动力的核心目标,河南省创新性地打造“办学理念+教师发展+科研帮带+学生培养+校园文化”的五位一体高等职业教育组团式援疆模式,以办学理念为指引,以教师发展为抓手,以科研帮带为手段,以学生培养为根本,以校园文化为基础,通过团、援、联三维联动,全面提升新疆受援高校发展实力,实现援疆工作从“输血”到“造血”的转变。

关键词：教育援疆高等职业教育组团式援疆对口支援

Total ionizing dose effects on graphene-based charge-trapping memory

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Science China(Information Sciences) 2019年第12期62卷 207-214页

作者： Kai XI Jinshun BI SANDip MAJUMDAR Bo LI Jing liu Yannan XU ming liu Laboratory of Microelectronics Devices and Integrated Technology Institute of MicroelectronicsChinese Academy of Sciences School of Microelectronics University of Chinese Academy of Sciences

This study investigates the total ionizing dose effects in graphene-based charge-trapping memory(GCTM) capacitors by using60 Co γ-irradiation. Electrical properties including C-V hysteresis window,gate leakage current, and flat band voltage shifts are evaluated with ionizing dose levels up to 1 Mrad(Si).The C-V hysteresis memory window is hardly affected by the irradiation. The gate leakage current increases with the increase of ionizing dose due to the multiple-trap assisted tunneling mechanism. Significant electrical degrade of the devices in programmed and erased states has been observed with the increase of the dose levels. Mechanisms behind the degradation are attributed to the photo-emission in the graphene nanodisc charge-trapping sets, radiation-induced holes trapping in the peripheral oxides, and the recombination of the stored electrons with the radiation-induced holes.

关键词： graphene non-volatile memories radiation trap-assisted tunneling leakage current