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转录因子HNF1α基因c.493T>C位点突变对其蛋白质水平的影响
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作者 梁淑杰 彭乙华 +3 位作者 雷佳红 贾艾敏 蒋红 蔡燕 《遗传》 CAS CSCD 北大核心 2024年第3期256-262,共7页
肝细胞核因子1α(hepatocyte nuclear factor 1α,HNF1α)作为一种转录因子在维持胰腺β细胞功能、肝脏脂质代谢等过程中发挥着重要的调控作用。该基因突变是导致青少年起病的成人型糖尿病(maturity onset diabetes of the young,MODY)... 肝细胞核因子1α(hepatocyte nuclear factor 1α,HNF1α)作为一种转录因子在维持胰腺β细胞功能、肝脏脂质代谢等过程中发挥着重要的调控作用。该基因突变是导致青少年起病的成人型糖尿病(maturity onset diabetes of the young,MODY)3型的致病原因,目前已报道的该基因的突变位点众多,如P291fsinsC、P112L等常见的突变位点,但其具体的分子机制尚不清楚。本研究对前期工作中发现的1例携带有HNF1α基因c.493T>C位点突变的MODY3患者,通过应用Mutation Surveyor软件分析突变位点的致病性,构建HNF1α野生型和突变型真核表达质粒,采用Western blot检测两种质粒表达的HNF1α蛋白质的量和稳定性变化,结果发现Mutation Surveyor软件分析提示c.493T>C位点突变可能为致病性变异基因,Western blot显示突变型真核质粒表达的HNF1α蛋白质的量和稳定性均明显降低,差异均具有统计学意义(P<0.05)。上述结果表明c.493T>C(p.Trp165Arg)变异显著影响HNF1α的表达量及稳定性,可能为其导致疾病发生的原因,为后续深入探究MODY3的分子致病机制提供了新的方向。 展开更多
关键词 MODY HNF1α 基因突变
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Hollow ZIF-67-derived Co@N-doped carbon nanotubes boosting the hydrogenation of phenolic compounds to alcohols
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作者 Zhihao Guo Jiuxuan Zhang +3 位作者 Lanlan Chen Chaoqun Fan hong jiang Rizhi Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期157-166,共10页
The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named... The selective hydrogenation of highly toxic phenolic compounds to generate alcohols with thermal stability,environmental friendliness,and non-toxicity is of great importance.Herein,a series of Co-based catalysts,named Co@NCNTs,were designed and constructed by direct pyrolysis of hollow ZIF-67(HZIF-67)under H_(2)/Ar atmosphere.The evolution of the catalyst surface from the shell layer assembled by ZIF-67-derived particles to the in situ-grown hollow nitrogen-doped carbon nanotubes(NCNTs)with certain length and density is achieved by adjusting the pyrolysis atmosphere and temperature.Due to the synergistic effects of in situ-formed hollow NCNTs,well-dispersed Co nanoparticles,and intact carbon matrix,the as-prepared Co@NCNTs-0.10-450 catalyst exhibits superior catalytic performance in the hydrogenation of phenolic compounds to alcohols.The turnover frequency value of Co@NCNTs-0.10-450is 3.52 h^(-1),5.9 times higher than that of Co@NCNTs-0.40-450 and 4.5 times higher than that of Co@NCNTs-0.10-550,exceeding most previously reported non-noble metal catalysts.Our findings provide new insights into the development of non-precious metal,efficient,and cost-effective metal-organic framework-derived catalysts for the hydrogenation of phenolic compounds to alcohols. 展开更多
关键词 Phenolic compounds Hollow ZIF-67 pyrolysis Nitrogen-doped carbon nanotubes Reduction Multiphase reaction Catalysis
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女性油性敏感皮肤面部生理参数与菌群特征分析
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作者 蒋虹 姜姗姗 +3 位作者 袁春颖 杨素珍 韩婷婷 李燕 《日用化学工业(中英文)》 CAS 北大核心 2024年第8期966-973,共8页
通过自我敏感评价问卷和皮脂分泌量的测定将人群分为健康皮肤非敏感型人群和油性皮肤敏感型人群,采用无创伤性皮肤测量和扩增子测序的方法对健康皮肤人群和油性敏感皮肤人群的皮肤生理特点和菌群组成进行研究。研究发现,与健康皮肤人群... 通过自我敏感评价问卷和皮脂分泌量的测定将人群分为健康皮肤非敏感型人群和油性皮肤敏感型人群,采用无创伤性皮肤测量和扩增子测序的方法对健康皮肤人群和油性敏感皮肤人群的皮肤生理特点和菌群组成进行研究。研究发现,与健康皮肤人群相比,油性敏感皮肤人群的皮肤含水量和b值显著降低(P<0.05),经皮水分流失率、皮脂、血红素和皮肤粗糙度显著升高(P<0.05),毛孔面积显著增大(P<0.05);皮肤菌群多样性分析表明Sobs指数(P<0.05)和Shannon指数显著降低(P<0.001),菌群多样性降低;物种组成分析表明,丙酸杆菌属和葡萄球菌属丰度明显上升,红球菌属和假单胞菌属丰度显著下降(P<0.001);斯皮尔曼相关性分析表明,皮脂与丙酸杆菌属和葡萄球菌属呈正相关,与其他菌属呈负相关性;且在皮肤生理参数和物种组成部分加入油性不敏感数据对比发现,这种皮肤也处于不健康的皮肤状态,其生理参数和皮肤菌群组成变化与油性敏感皮肤呈相同的变化趋势,但整体均好于油性敏感皮肤。通过以上结果分析得到,油性敏感皮肤的产生与皮肤菌群的变化密切相关,且丙酸杆菌属是影响皮肤菌群组成整体稳定性的重要菌属,以上研究结果将为油性敏感皮肤人群护肤品的开发提供科学依据。 展开更多
关键词 油性皮肤 油性敏感皮肤 皮肤生理参数 皮肤菌群
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Percutaneous transhepatic cholangioscopy-assisted biliary polypectomy for local palliative treatment of intraductal papillary neoplasm of the bile duct
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作者 Xu Ren Yong-Ping Qu +4 位作者 Chun-Lan Zhu Xiao-hong Xu hong jiang Yi-Xia Lu hong-Peng Xue 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1821-1832,共12页
BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a premalignant biliarytype epithelial neoplasm with intraductal papillary or villous growth.Currently reported local palliative therapeutic modalities... BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB)is a premalignant biliarytype epithelial neoplasm with intraductal papillary or villous growth.Currently reported local palliative therapeutic modalities,including endoscopic nasobiliary drainage,stenting and biliary curettage,endoscopic biliary polypectomy,percutaneous biliary drainage,laser ablation,argon plasma coagulation,photodynamic therapy,and radiofrequency ablation to relieve mechanical obstruction are limited with weaknesses and disadvantages.We have applied percutaneous transhepatic cholangioscopy(PTCS)-assisted biliary polypectomy(PTCS-BP)technique for the management of IPNB including mucin-hypersecreting cast-like and polypoid type tumors since 2010.AIM To assess the technical feasibility,efficacy,and safety of PTCS-BP for local palliative treatment of IPNB.METHODS Patients with mucin-hypersecreting cast-like or polypoid type IPNB and receiving PTCS-BP between September 2010 and December 2019 were included.PTCS-BP was performed by using a half-moon type snare with a soft stainless-steel wire,and the tumor was snared and resected with electrocautery.The primary outcome was its feasibility,indicated by technical success.The secondary outcomes were efficacy,including therapeutic success,curative resection,and clinical success,and safety.RESULTS Five patients(four with mucin-hypersecreting cast-like type and one with polypoid type IPNB)were included.Low-and high-grade intraepithelial neoplasia(HGIN)and recurrent IPNB with invasive carcinoma were observed in one,two,and two patients,respectively.Repeated cholangitis and/or obstructive jaundice were presented in all four patients with mucin-hypersecreting cast-like type IPNB.All five patients achieved technical success of PTCS-BP.Four patients(three with mucin-hypersecreting cast-like type and one with polypoid type IPNB)obtained therapeutic success;one with mucin-hypersecreting cast-like type tumors in the intrahepatic small bile duct and HGIN had residual tumors.All four patients with mucin-hypersecreting IPNB achieved clinical success.The patient with polypoid type IPNB achieved curative resection.There were no PTCS-BP-related serious adverse events.CONCLUSION PTCS-BP appears to be feasible,efficacious,and safe for local palliative treatment of both mucin-hypersecreting cast-like and polypoid type IPNB. 展开更多
关键词 Intraductal papillary neoplasm of the bile duct Percutaneous transhepatic cholangioscopy Biliary polypectomy FEASIBILITY EFFICACY
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Mediating role of social support in dysphoria,despondency,and quality of life in patients undergoing maintenance hemodialysis
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作者 Xiang Zhou hong jiang +4 位作者 Yi-Peng Zhou Xiao-Yu Wang Hai-Yan Ren Xue-Fei Tian Qing-Qing Zhang 《World Journal of Psychiatry》 SCIE 2024年第3期409-420,共12页
BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can signif... BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD.Currently,there is limited research on how social support mediates the relationship between dysphoria,despondency,and overall QOL in patients undergoing MHD.It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD,ultimately enhancing their overall QOL.AIM To investigate the mediating role of social support in relationships between dysphoria,despondency,and QOL among patients undergoing MHD.METHODS Participants comprised 289 patients undergoing MHD,who were selected using a random sampling approach.The Social Support Rating Scale,Self-Rating Anxiety Scale,Self-Rating Depression Scale,and QOL Scale were administered.Correlation analysis was performed to examine the associations between social support,dysphoria,despondency,and QOL in patients undergoing MHD.To assess the mediating impact of social support on dysphoria,despondency,and QOL in patients undergoing MHD,a bootstrap method was applied.RESULTS Significant correlations among social support,dysphoria,despondency,and quality in patients undergoing MHD were observed(all P<0.01).Dysphoria and despondency negatively correlated with social support and QOL(P<0.01).Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD(P<0.05).The direct effect of dysphoria on QOL was statistically significant(P<0.05).Social support mediated the relationship between dysphoria and QOL,and this mediating effect was significant(P<0.05).Similarly,the direct effect of despondency on QOL was significant(P<0.05).Moreover,social support played a mediating role between despondency and QOL,with a significant mediating effect(P<0.05).CONCLUSION These findings suggest that social support plays a significant mediating role in the relationship between dysphoria,despondency,and QOL in patients undergoing MHD. 展开更多
关键词 Maintenance hemodialysis Social support DYSPHORIA Despondency Quality of life Mediating effect
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Literary Reading Intervention Strategies for Adolescents with Depression
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作者 hong jiang 《Journal of Contemporary Educational Research》 2024年第7期133-137,共5页
Teenagers are in the special stage of physical and mental development,and their psychological problems show complex and diverse characteristics.Depression is the most common mental disorder among teenagers.Literary re... Teenagers are in the special stage of physical and mental development,and their psychological problems show complex and diverse characteristics.Depression is the most common mental disorder among teenagers.Literary reading has a certain intervention effect on depression and can be used as an important strategy for psychological intervention.Reading literature works can help teenagers understand and discover themselves from different angles,and then realize the self-recognition and intervention of depression.This paper mainly discusses the causes of depression in teenagers and the intervention principles and strategies of literary reading on depression,aiming to alleviate and eliminate the depressive symptoms of teenagers through literary reading and promote their physical and mental health development. 展开更多
关键词 DEPRESSION Literary reading Intervention strategy
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基于电子鼻技术对不同黑木耳品种香气的差异性分析研究 被引量:1
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作者 黄静 洪江 +4 位作者 向准 和耀威 刘忠玄 李鹏 汪建文 《贵州科学》 2023年第3期11-15,共5页
以25个不同的黑木耳品种为供试材料,利用电子鼻技术对香气成分进行检测,探讨不同品种黑木耳的香气特征。结果表明:经电子鼻检测后,各传感器对不同品种黑木耳香气成分的差异显著不同,W3C传感器差异不显著,W1W等9个传感器均对不同品种黑... 以25个不同的黑木耳品种为供试材料,利用电子鼻技术对香气成分进行检测,探讨不同品种黑木耳的香气特征。结果表明:经电子鼻检测后,各传感器对不同品种黑木耳香气成分的差异显著不同,W3C传感器差异不显著,W1W等9个传感器均对不同品种黑木耳香气成分的差异显著(P<0.05)。主成分分析(PCA)和线性判别式分析(LAD)能够明显地区别不同品种黑木耳。传感器区别贡献率分析(Loadings)中,传感器WIW、W5S、W2W、W1S在鉴别不同品种黑木耳中起很大作用,即硫化物、萜烯类、含硫有机化合物和芳烃化合物的贡献比较大,其次是烷类和氮氧化物。 展开更多
关键词 黑木耳 PCA 电子鼻 贡献率
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Jahn-Teller Effect Directed Bandgap Tuning of Birnessite for Pseudocapacitive Application
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作者 Sheng Zhu Yuechao Wang +6 位作者 Jinshu Zhang Jian Sheng Feng Yang Meng Wang jiangfeng Ni hong jiang Yan Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期222-228,共7页
Birnessite M_(x)MnO_(2)(M=Na^(+),K^(+),etc.)has emerged as a promising alternative to the classical MnO_(2)material owing to its improved pseudocapacitive performance for energy storage.Understanding their structure–... Birnessite M_(x)MnO_(2)(M=Na^(+),K^(+),etc.)has emerged as a promising alternative to the classical MnO_(2)material owing to its improved pseudocapacitive performance for energy storage.Understanding their structure–property correlation is essential for the development and application of advanced supercapacitors.Herein,we adopt the crystal field theory and density functional simulation to reveal the structural dependence of the pseudocapacitive property of M_(x)MnO_(2).Attributing to the Jahn–Teller effect of Mn^(3+),the bandgap of Kx MnO_(2)can be tuned by changing the x value(i.e.,the Mn(III)/Mn(IV)ratio).Then,we design a narrow-bandgap K 0.25 MnO_(2)(0.84 eV),which affords a high capacitance of 415 F g^(-1)at 1 A g^(-1)and a desirable rate capability of 293 F g^(-1)at 20 A g^(-1).Operando Raman spectroscopy confirms that the Jahn–Teller induced structure evolution of[MnO_(6)]octahedron accounts for the superior pseudocapacitive behavior of K_(0.25)MnO_(2).This finding offers theoretical guidance to the design and application of birnessite materials for pseudocapacitors. 展开更多
关键词 BIRNESSITE charge storage Jahn–Teller effect manganese dioxide SUPERCAPACITOR
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Optimizing Power Allocation for D2D Communication with URLLC under Rician Fading Channel:A Learning-to-Optimize Approach
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作者 Owais Muhammad hong jiang +2 位作者 Mushtaq Muhammad Umer Bilal Muhammad Naeem Muhammad Ahtsam 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期3193-3212,共20页
To meet the high-performance requirements of fifth-generation(5G)and sixth-generation(6G)wireless networks,in particular,ultra-reliable and low-latency communication(URLLC)is considered to be one of the most important... To meet the high-performance requirements of fifth-generation(5G)and sixth-generation(6G)wireless networks,in particular,ultra-reliable and low-latency communication(URLLC)is considered to be one of the most important communication scenarios in a wireless network.In this paper,we consider the effects of the Rician fading channel on the performance of cooperative device-to-device(D2D)communication with URLLC.For better performance,we maximize and examine the system’s minimal rate of D2D communication.Due to the interference in D2D communication,the problem of maximizing the minimum rate becomes non-convex and difficult to solve.To solve this problem,a learning-to-optimize-based algorithm is proposed to find the optimal power allocation.The conventional branch and bound(BB)algorithm are used to learn the optimal pruning policy with supervised learning.Ensemble learning is used to train the multiple classifiers.To address the imbalanced problem,we used the supervised undersampling technique.Comparisons are made with the conventional BB algorithm and the heuristic algorithm.The outcome of the simulation demonstrates a notable performance improvement in power consumption.The proposed algorithm has significantly low computational complexity and runs faster as compared to the conventional BB algorithm and a heuristic algorithm. 展开更多
关键词 D2D URLLC rician fading supervised learning
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Slot双下肢全长摄影在全膝关节置换术中的应用价值 被引量:13
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作者 韩瑞 董进 +3 位作者 蒋鸿 孙秋 梅海清 蒋宇宏 《中国现代医学杂志》 CAS 2018年第9期108-112,共5页
目的探讨动态平板透视的狭缝全景摄影技术(Slot)双下肢全长摄影在膝关节置换术的临床应用价值。方法回顾性分析2013年11月-2017年3月89例膝关节置换患者,共99个膝关节进行全膝关节置换术,每位患者在手术前后分别使用动态平板透视摄影系... 目的探讨动态平板透视的狭缝全景摄影技术(Slot)双下肢全长摄影在膝关节置换术的临床应用价值。方法回顾性分析2013年11月-2017年3月89例膝关节置换患者,共99个膝关节进行全膝关节置换术,每位患者在手术前后分别使用动态平板透视摄影系统的狭缝全景技术进行负重位的双下肢全长摄影,采用0~2分的评分方式对图像质量进行评估,0分图像质量差,1分图像质量中等,2分者为图像质量优良,并在图像质量优良的图片上通过后处理软件对患者的手术膝进行术前和术后下肢力线及胫股角进行测量,对术前进行全面评估,同时通过对比分析评价手术效果。结果 (1)89例患者Slot双下肢全长摄像一次成功率100%,成像时间短,操作简便、快捷,每位患者图像质量评分均为2分,质量优良,完全满足诊断及临床的要求;(2)89例患者术前均得到全面准确的评估,80例为骨性关节炎,9例为创伤性骨关节炎,其中,合并膝内翻畸形17例,膝外翻畸形患者8例,无合并内外翻畸形者64例;(3)术后所有患者假体对位、对线良好,假体周围无骨折,所有患者下肢力线和胫股角均为正常范围,17例膝关节内翻畸形患者,胫股角手术前后比较差异有统计学意义(t=-6.590,P=0.000);8例膝外翻畸形患者,胫股角手术前后比较差异有统计学意义(t=5.597,P=0.001),膝内外翻畸形较术前均得到良好的校正;无合并内外翻畸形64例患者术后下肢力线与重力垂线夹角和胫股角与手术前后比较,差异无统计学意义(t_(前者)=0.725,P=0.487,t_(后者)=-2.090,P=0.070)。结论使用狭缝全景摄影技术对双下肢全长进行成像,其成功率高、检查时间短、辐射剂量低,且图像拼接操作简便,质量优良,满足临床诊断需求,对临床术前手术方案制定及术后评估具有重要应用价值。 展开更多
关键词 狭缝全景摄影技术 下肢 膝关节置换术 膝内翻畸形 膝外翻畸形
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贵州稀有濒危种子植物物种多样性保护与利用的研究 被引量:7
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作者 邹天才 李媛媛 +5 位作者 洪江 黄丽华 刘海燕 陈龙 张著林 张维 《广西植物》 CAS CSCD 北大核心 2021年第10期1699-1706,I0006-I0016,共19页
全球性生物多样性保护与利用正逐步走向高质量发展,拥有丰富物种资源已成为夺取生物科技制高点的关键,因此,贵州稀有濒危种子植物多样性保护与利用的研究具有重要意义。在对贵州稀有濒危种子植物资源调查的基础上,选取具有重要应用价值... 全球性生物多样性保护与利用正逐步走向高质量发展,拥有丰富物种资源已成为夺取生物科技制高点的关键,因此,贵州稀有濒危种子植物多样性保护与利用的研究具有重要意义。在对贵州稀有濒危种子植物资源调查的基础上,选取具有重要应用价值的小黄花茶(Camellia luteoflora)、贵州红山茶(C.kweichowensis)等103种贵州稀有濒危植物,采用模式标本产地植物追溯、现存分布区及种群散布特征调查、物种濒危等级评估、混合采种迁地保育、生物资源测试分析与资源评价相结合的方法,开展了植物物种多样性编目及其迁地保护、种子生物学特性与种子散布及分布动态变化、种苗繁育与应用栽培试验等研究。结果表明:(1)调查评估的103种贵州稀有濒危种子植物都采取了就地保护措施,但迄今为止对濒危威胁程度减轻的效应不明显,抢救性迁地保护依然必要,其中极危(CR)23种、濒危(EN)30种、易危(VU)40种、近危(NT)7种、无危(LC)3种;采用同一地理种源迁地保护有效种群P_(n)≥L_(f)·E_(e)·A_(m)的栽培方法,在贵州省植物园开展了迁地保护引种栽培试验。其中,国家重点保护野生植物33种、3650株,引种栽培平均成活率为95.47%,贵州及毗邻川、滇、桂极少数地区特有分布的种子植物70种、11010株,引种栽培平均成活率为95.80%,并且建成了活植物保育圃30200 m^(2)。(2)搜集文献大数据结合GIS信息追踪调查研究,发现了小黄花茶新分布区2.5 km^(2)、长柱红山茶(C.longistyla)新分布区1.5 km^(2)、美丽红山茶(C.delicata)新分布区1.0 km^(2)、皱叶瘤果茶(C.rhytidophylla)新分布区6.0 km^(2)、红花瘤果茶(C.rubituberculata)新分布区50.0 km^(2)、贵州槭(Acer guizhouensis)新分布区0.3 km^(2);新分布区种群增量对其减轻濒危程度的评估效果影响不明显。(3)选择了小黄花茶、贵州红山茶等20种具有贵州高原区域环境特色的经济植物开展了种苗繁育和应用栽培试验,建立种苗繁育基地13.4 hm^(2),繁育种苗73万余株,在林业绿化工程应用中示范栽培140.0 hm^(2)(31万株),≥2年生苗木应用栽培存活率92.00%~98.00%,这为有关稀有濒危植物的科学研究及种质创新利用提供科学参考。 展开更多
关键词 稀有濒危植物 贵州特有分布 濒危等级评价 迁地保护 应用栽培
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鸟王茶不同叶片外观表现型与季节下茶叶产量与品质研究 被引量:7
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作者 张家春 周颖 +4 位作者 李朝桢 周鑫伟 洪江 张清海 张珍明 《四川农业大学学报》 CSCD 北大核心 2021年第1期35-40,共6页
【目的】为筛选出鸟王茶产量及品质比较稳定的优良单株,为进一步选育高产优质鸟王茶品种奠定基础。【方法】以鸟王茶3个主要的栽培叶片外观表现型为对象,研究鸟王茶叶片外观表现型种类的生物量的变化趋势,对不同采摘季节鸟王茶矿质元素... 【目的】为筛选出鸟王茶产量及品质比较稳定的优良单株,为进一步选育高产优质鸟王茶品种奠定基础。【方法】以鸟王茶3个主要的栽培叶片外观表现型为对象,研究鸟王茶叶片外观表现型种类的生物量的变化趋势,对不同采摘季节鸟王茶矿质元素、儿茶素、茶多酚、咖啡碱等茶叶品质指标进行分析,综合讨论不同叶片外观表现型和采摘季节下鸟王茶的产量及品质。【结果】年萌枝数和发芽密度为小叶型>中叶型>大叶型、一芽一叶百芽重量为大叶型>中叶型>小叶型;Ca含量为夏茶>秋茶>春茶、Fe和Mg为秋茶>春茶>夏茶、Se和Zn为春茶>秋茶>夏茶;水浸出物、总儿茶素为夏茶>秋茶>春茶,茶多酚为秋茶>夏茶>春茶,咖啡碱为夏茶>春茶>秋茶。【结论】鸟王茶不同叶片外观表现型春茶的生化指标适制优质绿茶,夏、秋芽的生化指标适制优质红茶;中叶型可以作为单株优选育种材料,大叶型可试制乌龙茶产品。 展开更多
关键词 鸟王茶 叶片外观表现型 矿质元素 品质 季节
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基于MOOC“一站式”有机化学在线翻转课堂实践 被引量:28
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作者 曹敏惠 石炜 +1 位作者 江洪 徐胜臻 《大学化学》 CAS 2020年第5期147-151,共5页
新型冠状病毒(COVID-19)疫情下,为了响应教育部“停课不停学,停课不停教”,实现在线教学和线下课堂同质等效,本文依托中国大学MOOC平台,以在线开放课程有机化学为线上学习资源,建立校内SPOC课程,借助慕课堂,实现在线翻转课堂。课前学生... 新型冠状病毒(COVID-19)疫情下,为了响应教育部“停课不停学,停课不停教”,实现在线教学和线下课堂同质等效,本文依托中国大学MOOC平台,以在线开放课程有机化学为线上学习资源,建立校内SPOC课程,借助慕课堂,实现在线翻转课堂。课前学生学习视频,自学自测;直播赋能解惑,互动参与;课后举一反三,巩固提高。“一站式”解决了在线翻转课堂三阶段的学习需求,初步探讨了在线翻转课堂教学实践的关键因素。 展开更多
关键词 在线教学 中国大学MOOC 翻转课堂 有机化学
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喀斯特小流域土壤质量特征研究 被引量:9
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作者 黄先飞 洪江 张家春 《贵州师范大学学报(自然科学版)》 CAS 2018年第4期18-22,共5页
为阐明喀斯特小流域土壤质量特征及其主要影响因素,通过2 755个样点信息收集与土壤样品采集,定量研究了流域土壤主要理化性质和有机碳含量。结果表明:喀斯特小流域土壤物理特性存在不同程度的异质性,其中剖面土壤容重平均值范围为1.17~1... 为阐明喀斯特小流域土壤质量特征及其主要影响因素,通过2 755个样点信息收集与土壤样品采集,定量研究了流域土壤主要理化性质和有机碳含量。结果表明:喀斯特小流域土壤物理特性存在不同程度的异质性,其中剖面土壤容重平均值范围为1.17~1.41 g/cm^3;随着土壤厚度增加,土壤容重先增加后趋于稳定;整个后寨河流域内土层厚度大于100 cm的区域占流域总面积的51.32%;不同土属分区土壤厚度差异较大,黄泥田区土壤厚度大多超过100 cm,而黑色石灰土区则大部分厚度小于20 cm,部分区域甚至仅几厘米。流域内23 536个土壤样品的有机质平均含量为28.27 g/kg,变幅为0.22~221.95 g/kg,极差为221.73 g/kg,结果显示,范围较宽,最大值是最小值的1 008.86倍。本研究表明后寨河流域土壤质量空间差异较大,表层土壤有机质含量较高,98%以上的表层土壤肥力皆在较适中以上。土壤厚度及石砾含量等受地形地貌影响较大。 展开更多
关键词 土壤质量 物理性质 有机质 小流域 喀斯特
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核磁共振原理中几个基本概念的教学处理 被引量:8
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作者 马忠华 曹秀芳 +1 位作者 江洪 马济美 《大学化学》 CAS 2021年第4期236-244,共9页
核磁共振是解析有机化合物结构的一种常用的方法,也是波谱学课程教学中的重点内容之一。核磁共振原理中的几个基本概念(磁性核、核自旋、角动量、磁旋比、电四极矩)和原子核内部能级在外磁场中的变化等,是对核磁共振深入认知和理解不可... 核磁共振是解析有机化合物结构的一种常用的方法,也是波谱学课程教学中的重点内容之一。核磁共振原理中的几个基本概念(磁性核、核自旋、角动量、磁旋比、电四极矩)和原子核内部能级在外磁场中的变化等,是对核磁共振深入认知和理解不可或缺的内容。本文探讨了在教学中如何合理地对这些内容所涉及的量子物理学的原理进行简化处理,并结合化学学科内容进行阐释,从而使学生更好地掌握核磁共振分析手段,培养学生科学系统地思考、剖析问题的能力,拓展学生的思维能力与认知,培养学生对自然学科发展规律的正确认识,以及正确的科学价值取向。 展开更多
关键词 核磁共振 磁性核 磁旋比 核磁矩 角动量
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全球激光焊接专利技术研究进展 被引量:3
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作者 曹晨 江洪 叶茂 《激光杂志》 CAS 北大核心 2021年第2期1-4,共4页
通过对全球激光焊接技术领域的专利数据进行统计分析,结合对具体专利内容的解读,从专利申请趋势、区域市场布局、研发机构实力、热点技术主题等角度揭示全球激光焊接技术的研究进展。近10年来中国激光焊接专利技术高速发展,研发热情依... 通过对全球激光焊接技术领域的专利数据进行统计分析,结合对具体专利内容的解读,从专利申请趋势、区域市场布局、研发机构实力、热点技术主题等角度揭示全球激光焊接技术的研究进展。近10年来中国激光焊接专利技术高速发展,研发热情依然高涨,但国内专利整体缺乏海外市场布局;激光复合焊接工艺与方法、智能激光焊接技术与设备、非金属材料激光焊接是当前激光焊接领域的技术研发热点;未来可重点关注焊接过程的实时监测与质量控制、新型传感器技术、多功能自动化焊接设备、异种和复合焊接材料等技术领域的研发动向。 展开更多
关键词 激光焊接 专利分析 热点技术
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Efficacy of a new mutated recombinant tissue-type plasminogen activator in beagles with acute coronary artery thrombi
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作者 Jing Bai Lin-bo Yc +2 位作者 hong jiang Dong-dong Zhao hong-yao Hu 《World Journal of Emergency Medicine》 SCIE CAS 2010年第2期126-131,共6页
BACKGROUND: Development of new coronary thrombolytic agents is hot in the market. A new drug, mutated recombinant tissue-type plasminogen activator (rtPAm), is the product of mutation of tPA by changing binding loc... BACKGROUND: Development of new coronary thrombolytic agents is hot in the market. A new drug, mutated recombinant tissue-type plasminogen activator (rtPAm), is the product of mutation of tPA by changing binding loci with plasminogen activator inhibitor (PAl)-1 to reduce the degradation. In vitro test has demonstrated that the activity of rtPAm is much higher than rtPA in the absence of PAl. The present study is to observe the efficacy of mutated recombinant tissue-type plasminogen activator (rtPAm) in coronary thrombolytic therapy.METHODS: A total of 30 adult beagles were equally divided into 5 groups after thrombi: vehicle group, urokinase group, rtPAm low-dose group, rtPAm medium-dose group, and rtPAm high-dose group. Thrombolytic effect and myocardial infarction were observed after thrombolytic therapy.RESULTS: In the urokinase group, time to reperfusion was (15.8±3.8) minutes. TIMI 2 flow was demonstrated in 4 beagles, TIMI 3 flow in 2, and re-occlusion in 4 after 90 minutes respectively. In the low- dose rtPAm group, time to reperfusion was (15±4.5) minutes; TIMI 2 flow was demonstrated in 2 beagles, TIMI 3 flow in 4, and re-occlusion in 2 after 90 minutes. In the high-dose rtPAm group, time to reperfusion was (7.5±2.6) minutes. None of the beagles showed re-occlusion after 90 minutes. The infarction areas were (2.1±0.9)% in the medium-dose rtPAm group and (0.7±0.4)% in the high-dose rtPAm group, which decreased significantly than those in the low-dose rtPAm group. The aggregation rate in the medium-dose and high-dose rtPAm groups decreased significantly than that in the urokinase group.CONCLUSION: rtPAm may serve as a thrombolytic agent with platelet-targeted fibrinolysis and antiplatelet aggregation activities. 展开更多
关键词 UROKINASE RTPA THROMBI D-dime Platelet aggregation
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归一化全矢能量在随机工况下齿轮微弱故障识别中的应用(英文) 被引量:1
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作者 章翔峰 姜宏 冉祥锋 《机床与液压》 北大核心 2019年第18期77-84,共8页
随机工况下,转速和负载的不同会改变振动信号的幅频调制特性,使得风电机组齿轮箱局部微弱故障的诊断难度急剧增大,针对于此,提出采用不同的恒定工况替代随机工况,以归一化全矢频带能量实现随机工况下齿轮箱微弱故障的诊断。方法首先将... 随机工况下,转速和负载的不同会改变振动信号的幅频调制特性,使得风电机组齿轮箱局部微弱故障的诊断难度急剧增大,针对于此,提出采用不同的恒定工况替代随机工况,以归一化全矢频带能量实现随机工况下齿轮箱微弱故障的诊断。方法首先将随机工况分解成不同的恒定工况的组合,降低工况的维数,针对各恒定工况,采用全矢理论将同源信号进行融合,以保证微弱信号源信息的完整性,再利用FIR滤波对全矢信号进行分解,消除因工况的不同所造成的模态混叠的影响。考虑到转频处的频带能量能定量区分不同的工况,频带能量的变化率能实现齿轮工作状态的区分,而信息熵能准确反映信号激励源和激励方式的区别,提取各频带能量熵之和、转频处的频带能量及频带能量的变化率作为区分齿轮工作状态的特征向量,消除工况变化所造成的诊断干扰的同时有利于实现各种工况下的故障模式识别,达到随机工况下齿轮微弱故障诊断的目的。最后采用高斯混合模型对风电机组齿轮箱随机工况下的150组振动信号进行特征描述,运用最大贝叶斯分类器实现故障识别,故障识别率表明该方法可有效的识别随机工况下的齿轮早期局部微弱故障。 展开更多
关键词 随机条件 全矢理论 能量熵 带能率 故障识别
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中国贵州药用真菌资源Ⅰ子囊菌门 被引量:4
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作者 汪建文 洪江 邓春英 《贵州科学》 2018年第5期18-23,共6页
在文献整理和资源调查的基础上,对贵州省药用真菌资源进行收集和整理。贵州省药用大型真菌包含子囊菌门39种,隶属于3纲,4目,10科16属。同时对每个学名按最新命名法规进行了订正,按拉丁学名字母进行排序,对每一种类的药用状况进行考证,... 在文献整理和资源调查的基础上,对贵州省药用真菌资源进行收集和整理。贵州省药用大型真菌包含子囊菌门39种,隶属于3纲,4目,10科16属。同时对每个学名按最新命名法规进行了订正,按拉丁学名字母进行排序,对每一种类的药用状况进行考证,为进一步研究和开发利用贵州省药用菌资源提供参考。 展开更多
关键词 抗肿瘤活性 抗氧化 抗菌 真菌
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贵州草海湿地生态环境现状及其评价 被引量:3
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作者 洪江 张家春 +1 位作者 江波 张珍明 《贵州科学》 2018年第5期62-66,共5页
草海是我国最大的高原淡水湖泊,因特殊的地理位置关系,草海湖泊接纳了来自区域内生产生活产生的各种污染物质,加之草海作为一个脆弱的生态系统,对抗外界干扰的能力差,在流域强烈的外界人类活动干扰下,草海脆弱的生态环境逐渐退化。在草... 草海是我国最大的高原淡水湖泊,因特殊的地理位置关系,草海湖泊接纳了来自区域内生产生活产生的各种污染物质,加之草海作为一个脆弱的生态系统,对抗外界干扰的能力差,在流域强烈的外界人类活动干扰下,草海脆弱的生态环境逐渐退化。在草海高原湿地,面对巨大的农业生产与旅游开发中的人为干扰,急需对生态环境进行改善和治理。综合分析了造成草海地区主要环境污染的污染源、污染物的种类及分布特征,并对草海湿地污染情况进行评价,以期为草海湿地土壤环境的保护提供理论依据。 展开更多
关键词 污染源 主要因子 评价 草海湿地
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