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慢性心力衰竭合并原发性高血压病患者死亡预警指标研究

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中国中西医结合杂志 2024年第9期44卷 1051-1062页

作者：李润民戴国华高武霖管慧任丽丽王兴蒙曲惠文山东中医药大学第一临床医学院济南250014 山东中医药大学附属医院老年医学科济南250014 山东中医药大学附属医院急诊与重症医学科济南250014 山东中医药大学中医学院济南250014

目的基于多重支持向量机-递归特征消除(MSVM-RFE)与Cox回归分析慢性心力衰竭(心衰)合并原发性高血压病患者发生易损期心源性死亡的中西医预警指标。方法将山东省7家中医院符合研究标准的慢性心衰合并原发性高血压病患者纳入前瞻性队列研... 详细信息

目的基于多重支持向量机-递归特征消除(MSVM-RFE)与Cox回归分析慢性心力衰竭(心衰)合并原发性高血压病患者发生易损期心源性死亡的中西医预警指标。方法将山东省7家中医院符合研究标准的慢性心衰合并原发性高血压病患者纳入前瞻性队列研究,收集患者基本信息、共患病、心脏彩超、实验室检查、中医证候信息、用药记录的78项临床变量,出院3个月后随访统计终点事件。运用Cox单因素回归筛选与易损期心源性死亡显著关联的变量,将其作为潜在预警指标纳入MSVM-RFE模型,经由计算平均排序分数对指标进行重要性排序。通过效能检验评估模型错误率与精准度筛选最优预警指标子集,并运用Cox多因素回归分析预警指标的作用性质。结果共1721例患者纳入分析,包含272例易损期心源性死亡病例。将Cox单因素回归分析获得的64个潜在预警指标依据重要性排序依次纳入MSVM-RFE模型进行效能检验,当纳入前13位潜在预警指标时,模型获得最小错误率0.136与最大精准度0.864,故将其作为最优预警指标子集。Cox多因素回归分析结果显示,血浆氨基末端脑利钠肽前体(NT-ProBNP)>1000 ng/L(HR=3.65);使用血管紧张素转换酶抑制剂/血管紧张素Ⅱ受体拮抗剂(ACEI/ARB,HR=0.66);气阴两虚血瘀证(HR=1.98);面色口唇紫暗(HR=2.19);使用利尿类药物(HR=0.73);心率60次/分或100次/分(HR=1.30,HR=1.33);年龄>60岁(HR=3.64);纽约心脏病学会(NYHA)心功能分级(Ⅲ级vsⅡ级:HR=2.50,Ⅳ级vsⅡ级:HR=3.58);吸烟史(HR=1.78);收缩压140 mmHg(HR=2.56);使用活血类注射液(HR=0.64);脉滑(HR=1.32);少苔或有裂纹(HR=1.45)。结论NT-ProBNP>1000 ng/L、气阴两虚血瘀证、面色口唇紫暗、心率60或100次/分、年龄>60岁、NYHA心功能分级Ⅲ级、吸烟史、收缩压140 mmHg、脉滑、少苔或有裂纹为损害性预警指标;使用ACEI/ARB、利尿类药物、活血类注射液为保护性预警指标。MSVM-RFE与Cox回归相结合的模型适配于高维、多重共线性、小样本数据的中西医预警指标分析。

关键词：慢性心力衰竭原发性高血压病心衰易损期中西医结合预警指标多重支持向量机-递归特征消除 Cox回归分析

Palladium-catalyzed oxidative cyclopropanation of enamides and norbornenes initiated by C–H activation

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Science China Chemistry 2018年第6期61卷 695-701页

作者： Ming Chen Mi-Na Zhao Yao-Du Zhang Zhi-hui Ren Zheng-hui guan Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Department of Chemistry & Materials Science Northwest University Shaanxi Key Laboratory of Phytochemistry College of Chemistry and Chemical Engineering Baoji University of Arts and Sciences

A novel palladium-catalyzed oxidative cyclopropanation of enamides and norbornenes has been developed. The reaction proceeded through palladium-catalyzed vinyl C–H bond activation of enamides followed by two migratory insertions, β-(N)H elimination and hydrolyzation cascade steps. The reaction tolerates a range of functional groups and provides an effective method for the synthesis of cyclopropane-fused norbornanes in good yields under mild conditions.

关键词： palladium-catalyzed cyclopropanation C–H activation enamides norbornenes

Characteristic and mechanism of Cr(Ⅵ) adsorption by ammonium sulfamate-bacterial cellulose in aqueous solutions

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Chinese Chemical Letters 2013年第3期24卷 253-256页

作者： Min Lu Xiao-hui guan Xiao-hui Xu De-Zhou Wei School of Chemical Engineering Northeast Dianli University School of Resources & Civil Engineering Northeastern University

A new adsorbent, ammonium sulfamate-bacterial cellulose （ASBC）, was prepared through chemical modifications of bacterial cellulose. The process of adsorbing Cr（VI） including its isotherm and kinetics, was measured and studied. The results showed that pH value was a very important parameter to the adsorbing efficiency. The adsorption kinetics can be described by a pseudo-second rate model and a particle diffusion equation. Both physical and chemical adsorptions existed in the adsorption process, but chemical adsorption was more dominatant. And particles internal diffusion was not the only rate controlling step. The adsorption equilibrium can be described by the Langmuir type, which indicated that a typical single-molecule layer adsorption of Cr（VI） by ASBC could be described. And the rate of adsorption followed the Slips model well, which indicated that ASBC had some multiphase and asymmetry. The coordination adsorption and ion exchange effect were the main mechanisms of chemical adsorption. The absorbed Cr（V1） can be desorbed effectively by 0.5 mol/L EDTA or HCI from the adsorbent, which could make it be reusable

关键词： Ammonium sulfamate-bacterial celluloseAdsorption characteristicAdsorption mechanismCr(Vl)

喷施糖醇钙和乳酸钙对‘蜜脆’苹果生理及品质的影响

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山东农业大学学报（自然科学版） 2024年第1期55卷 38-45页

作者：庄丽萍王朝管增辉张朋朋邹养军西北农林科技大学园艺学院陕西杨凌712100 延安水果产业研发中心陕西洛川727400

为探究糖醇钙和乳酸钙在‘蜜脆’苹果生长过程中对其生理及品质的影响。本实验以‘蜜脆’苹果为试材,在其生长期间喷施不同浓度糖醇钙和乳酸钙,以清水为对照,测定和分析不同处理对苹果生长发育指标、果实品质以及苦痘病发病率的影响。... 详细信息

为探究糖醇钙和乳酸钙在‘蜜脆’苹果生长过程中对其生理及品质的影响。本实验以‘蜜脆’苹果为试材,在其生长期间喷施不同浓度糖醇钙和乳酸钙,以清水为对照,测定和分析不同处理对苹果生长发育指标、果实品质以及苦痘病发病率的影响。结果表明,与对照相比,喷施适量钙肥总体上促进叶片生长,提高了苹果SPAD含量、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs),降低了叶片胞间CO_(2)浓度(Ci),显著增加了POD、SOD、CAT和Ca^(2+)-ATPase活性,提高了果实的单果质量、可溶性固形物,降低了果实可滴定酸含量,可促进果实着色,减少苦痘病的发生。因此,喷施不同浓度糖醇钙和乳酸钙,可提高‘蜜脆’苹果的单果重及果实品质,其中以乳酸钙1000倍效果最好。

关键词： ‘蜜脆’苹果钙肥果实品质生理生化特性

维普期刊数据库博看期刊

Removing Cd^(2+) by Composite Adsorbent Nano-Fe_3O_4/Bacterial Cellulose

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Chemical Research in Chinese Universities 2011年第6期27卷 1031-1034页

作者： LU Min guan Xiao-hui WEI De-zhou School of Chemical Engineering Northeast Dianli University Jilin 132012 P. R. China School of Resources ＆ Civil Engineering Northeastern University Shenyang 110004 P. R. China

A new composite adsorbent, nano-Fe3O4/bacterial cellulose（BC）, was prepared through blending method. The process of adsorbing Cd2＋ including its isotherm and kinetics measured was studied. The results show that the adsorption efficiency is improved because of huge surface area and surface coordination of nano-Fe3O4 particles. Its adsorption capacity is 27.97 mg/g and the maximum of Cd2＋ removal is 74%. The adsorption kinetics can be described by pseudo-second rate model and the adsorption equilibrium by Langmuir type. The superparamagnetism of nano-Fe3O4 particles can help to solve the difficult separation of single BC adsorbent and lead to the quick separation of composite adsorbent from the liquid if a magnetic field was applied. Cd2＋ can be desorbed effectively by EDTA and HCl from the composite adsorbent, which can make it be reused.

关键词： Nano-Fe3O4 Bacterial cellulose Composite adsorbent Cadmium ion

Prediction of the instability probability for rainfall induced landslides:the effect of morphological differences in geomorphology within mapping units

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Journal of Mountain Science 2023年第5期20卷 1249-1265页

作者： WANG Kai ZHANG Shao-jie XIE Wan-li guan hui School of Architecture and Civil Engineering Zhongyuan University of TechnologyZhengzhou 450007China Department of Geology State Key Laboratory of Continental DynamicsNorthwest UniversityXi′an 710069China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Slope units is an effective mapping unit for rainfall landslides prediction at regional *** present,slope units extracted by hydrology and morphological method report very different morphological feature and *** order to investigate the effect of morphological difference on the prediction performance,this paper presents a general landslide probability analysis model for slope *** Carlo method was used to describe the spatial uncertainties of soil mechanical parameters within slope units,and random search technique was performed to obtain the minimum safety factor;transient hydrological processes simulation was used to provide key hydrological parameters required by the model,thereby achieving landslide prediction driven by quantitative precipitation estimation and forecasting *** prediction performance of conventional slope units(CSUs)and homogeneous slope units(HSUs)were analyzed in three case studies from Fengjie County,*** results indicate that the mean missing alarm rate of CSUs and HSUs are 31.4% and 10.6%,*** Operating Characteristics(ROC)analysis also reveals that HSUs is capable of improving the overall prediction performance,and may be used further for rainfall-induced landslide prediction at regional scale.

关键词： Slope unit Boundaries Slope gradient Landslide prediction

PhI(OAc)2-promoted umpolung acetoxylation of enamides for the synthesis of α-acetoxy ketones

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Science China Chemistry 2017年第6期60卷 761-768页

作者： Ming Chen Wei Zhang Zhi-hui Ren Wen-Yun Gao Yao-Yu Wang Zheng-hui guan Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Department of Chemistry & Materials Science Northwest University Xi'an 710127 China College of Life Sciences/National Engineering Research Center for Miniaturized Detection Systems Northwest University Xi 'an 710069 China

Umpolung is a fundamental concept in organic chemistry, which provides an alternative strategy for the synthesis of target compounds which were not easily accessible by conventional methods. Herein, a mild and efficient PhI(OAc)_2-promoted umpolung acetoxylation reactions of enamides was developed for the synthesis of α-acetoxy ketones. The reaction tolerates a wide range of functional groups and affords α-acetoxy ketones in good to excellent yields. PhI(OAc)_2 serves as a source of acetoxy in the reaction.

关键词： umpolung enamides acetoxylation hypervalent iodine reagents α-acetoxy ketones

Base-mediated formal [3＋2] cycloaddition of β,γ-alkenyl esters and p-TsN3 for the synthesis of pyrazoles

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Science Bulletin 2017年第7期62卷 493-496页

作者： Mi-Na Zhao Mei-Na Zhang Zhi-hui Ren Yao-Yu Wang Zheng-hui guan Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Department of Chemistry & Materials ScienceNorthwest University

A novel 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU)-mediated formal cycloaddition of β,γ-alkenyl esters with p-tolylsulfonylazide(p-TsN_3) for the synthesis of 3,5-disubstituted pyrazoles has been *** reaction proceeded through diazotization of β,γ-alkenyl esters sequential with thermodynamic cyclization.p-Tolylsulfonylazide played a role as a source of two-nitrogen *** reaction employs readily available starting materials,tolerates a wide range of functional groups,and proceeds under mild conditions.

关键词： Synthetic methods Cycloaddition β,γ-Alkenylesters p-Tolylsulfonylazide Pyrazoles

Modulating the Electronic Structures of Single-walled Carbon Nanotubes by Filling with Electron Acceptors and the Effect on Their Reactivity with Aryl Diazonium Salts

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1911-1915页

作者： WANG Hong-Tao WU Chu-Xin guan Lun-hui State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences University of Chinese Academy of Sciences

The electronic structures of single-walled carbon nanotubes （SWCNTs） were modulated by filling with tetracyanoquinodimethane （TCNQ）, a strong electron acceptor. The structures of TCNQ-filled SWCNTs were checked by X-ray diffraction analysis, high-resolution transmission electron microscopy and Raman spectroscopy. Optical absorption spectroscopy demonstrated an enhanced reactivity between aryl diazonium and semiconducting SWCNTs.

关键词： carbon nanotubes electronic structures chemical reactivity doping