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Recovery of vanadium and carbon from low-grade stone coal by flotation 被引量:5
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作者 王丽 孙伟 张庆鹏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3767-3773,共7页
Flotation technology of high-carbon stone coal bearing vanadium was investigated based on mineralogical study. Carbon and vanadium flotation circuits were included in the flotation process for carbon and vanadium mine... Flotation technology of high-carbon stone coal bearing vanadium was investigated based on mineralogical study. Carbon and vanadium flotation circuits were included in the flotation process for carbon and vanadium mineral concentrates. Carbon and vanadium minerals were efficiently separated via regrinding process in the carbon flotation circuit. The results show that the grade and recovery of V2O5 in flotation concentrate are 1.32% and 88.38%, respectively, and the tailings yield is 38.36%. Meanwhile, the grade and recovery of the carbon mineral are 30.08% and 75.10%, respectively, which may be utilized as the fossil fuels directly. The leaching rates of the flotation products are as high as 85%. The results demonstrate that there is no direct adverse effect of flotation process on vanadium leaching. This technology could potentially reduce cost and increase the treatment capacity of vanadium extraction and provide reference to stone coal flotation technology. 展开更多
关键词 FLOTATION low grade stone coal VANADIUM CARBON
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热敏灸治疗颈型颈椎病的Meta分析及GRADE证据等级评价
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作者 周佳佳 邓秀红 +1 位作者 易媛媛 雷丽芳 《中国中医药现代远程教育》 2024年第7期107-110,共4页
目的系统评价热敏灸及其综合疗法用于颈型颈椎病的临床效果,为热敏灸治疗颈型颈椎病提供更好的证据来源。方法收集国内外各大数据库热敏灸及其综合疗法用于颈型颈椎病的随机对照试验(RCT),通过Revman 5.3软件进行Meta分析,按照GRADE标... 目的系统评价热敏灸及其综合疗法用于颈型颈椎病的临床效果,为热敏灸治疗颈型颈椎病提供更好的证据来源。方法收集国内外各大数据库热敏灸及其综合疗法用于颈型颈椎病的随机对照试验(RCT),通过Revman 5.3软件进行Meta分析,按照GRADE标准对结局指标进行证据质量评价。结果纳入9篇文献共855例患者,Meta分析结果提示:热敏灸及其综合疗法组在提高总有效率(RR=1.19,P<0.01)和治愈率(RR=1.73,P<0.01)、降低视觉模拟量表(VAS)评分(SMD=-0.73,P<0.01)、简化McGill疼痛问卷(SF-MPQ)评分(SMD=-1.28,P<0.05)以及NPQ颈痛量表评分(SMD=-0.81,P<0.05)方面都优于对照组;GRADE证据等级评价提示:前三者为低质量证据,后二者为极低质量证据。结论热敏灸及其综合疗法用于颈型颈椎病在提高临床效果、镇痛以及改善患者生活质量方面更具优势。 展开更多
关键词 颈型颈椎病 热敏灸 META分析 grade评价
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360° fusion for realignment of high grade cervical kyphosis by one step surgery: Case report 被引量:5
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作者 Alessandro Landi Nicola Marotta +3 位作者 Cristina Mancarella Demo Eugenio Dugoni Roberto Tarantino Roberto Delfini 《World Journal of Clinical Cases》 SCIE 2014年第7期289-292,共4页
Surgical treatment for cervical kyphotic deformity is still controversial. Circumferential approach has been well described in the literature but long terms outcomes are not well reported. Important to decide the corr... Surgical treatment for cervical kyphotic deformity is still controversial. Circumferential approach has been well described in the literature but long terms outcomes are not well reported. Important to decide the correct treatment option is the preoperative radiological exams to value the type of deformity(flexible or fixed). We report the case of a 67-year-old woman affected by a severe cervical kyphotic deformity who underwent combined anterior/posterior surgical approach, getting a good reduction of the deformity and an optimal stability in a long term follow up. 展开更多
关键词 CERVICAL DEFORMITY High grade KYPHOSIS Circumferential FUSION Surgical technique DEGENERATIVE CERVICAL spine
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Evaluation of umami taste components of mushroom (Suillus granulatus) of different grades prepared by different drying methods 被引量:7
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作者 Xiuhong Zhao Yunyun Wei +2 位作者 Xue Gong Heran Xu Guang Xin 《Food Science and Human Wellness》 SCIE 2020年第2期192-198,共7页
Suillus granulatus is a valuable wild edible mushroom with a strong umami taste.Different grades of S.granulatus were dried by different methods,including natural air drying(ND),hot air drying(HAD),vacuum drying(VD),a... Suillus granulatus is a valuable wild edible mushroom with a strong umami taste.Different grades of S.granulatus were dried by different methods,including natural air drying(ND),hot air drying(HAD),vacuum drying(VD),and freeze drying(FD).Results showed that VD samples of all grades had the highest equivalent umami concentration(EUC)value(P<0.05).The second grade of ND samples showed the highest EUC value(P<0.05).The first grade of HAD samples showed the highest EUC value(P<0.05).The third grade of FD samples showed the highest EUC value(P<0.05).The third grade of VD samples had a higher EUC value than the other grades of samples dried by VD.Electronic tongue results indicated no significant differences between samples of all grades dried by all methods.Thus,umami taste components are affected by drying method and grade.VD is an appropriate drying method for all sample grades.ND,HAD,and FD are suitable for second-,first-,and third-grade samples,respectively. 展开更多
关键词 Suillus granulatus drying methods grade umami taste components
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Theoretical study on the photonic band gap in one-dimensional photonic crystals with graded multilayer structure 被引量:3
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作者 范春珍 王俊俏 +2 位作者 何金娜 丁佩 梁二军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期242-246,共5页
We theoretically investigate the photonic band gap in one-dimensional photonic crystals with a graded multilayer structure. The proposed structure constitutes an alternating composite layer (metallic nanoparticles em... We theoretically investigate the photonic band gap in one-dimensional photonic crystals with a graded multilayer structure. The proposed structure constitutes an alternating composite layer (metallic nanoparticles embedded in TiO2 film) and an air layer. Regarding the multilayer as a series of capacitance, effective optical properties are derived. The dispersion relation is obtained with the solution of the transfer matrix equation. With a graded structure in the composite layer, numerical results show that the position and width of the photonic band gap can be effectively modulated by varying the number of the graded composite layers, the volume fraction of nanoparticles and the external stimuli. 展开更多
关键词 graded photonic crystals MULTILAYER band gap
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Symplectic analysis for regulating wave propagation in a one-dimensional nonlinear graded metamaterial 被引量:3
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作者 Yunping ZHAO Xiuhui HOU +1 位作者 Kai ZHANG Zichen DENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第5期745-758,共14页
An analytical method,called the symplectic mathematical method,is proposed to study the wave propagation in a spring-mass chain with gradient arranged local resonators and nonlinear ground springs.Combined with the li... An analytical method,called the symplectic mathematical method,is proposed to study the wave propagation in a spring-mass chain with gradient arranged local resonators and nonlinear ground springs.Combined with the linearized perturbation approach,the symplectic transform matrix for a unit cell of the weakly nonlinear graded metamaterial is derived,which only relies on the state vector.The results of the dispersion relation obtained with the symplectic mathematical method agree well with those achieved by the Bloch theory.It is shown that wider and lower frequency bandgaps are formed when the hardening nonlinearity and incident wave intensity increase.Subsequently,the displacement response and transmission performance of nonlinear graded metamaterials with finite length are studied.The dual tunable effects of nonlinearity and gradation on the wave propagation are explored under different excitation frequencies.For small excitation frequencies,the gradient parameter plays a dominant role compared with the nonlinearity.The reason is that the gradient tuning aims at the gradient arrangement of local resonators,which is limited by the critical value of the local resonator mass.In contrast,for larger excitation frequencies,the hardening nonlinearity is dominant and will contribute to the formation of a new bandgap. 展开更多
关键词 symplectic mathematical method nonlinear graded metamaterial tunable bandgap
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Stratification of outcomes for mucinous appendiceal adenocarcinoma with peritoneal metastasis by histological grade 被引量:2
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作者 Travis Edward Grotz Richard E Royal +8 位作者 Paul F Mansfield Michael James Overman Gary N Mann Kristen Ashlee Robinson Karen A Beaty Safiea Rafeeq Auerlio Matamoros Michelle W Taggart Keith Francis Fournier 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2017年第9期354-362,共9页
AIM To investigate the importance of a three-tiered histologic grade on outcomes for patients with mucinous appendiceal adenocarcinoma(MAA).METHODS Two hundred and sixty-five patients with MAA undergoing cytoreductive... AIM To investigate the importance of a three-tiered histologic grade on outcomes for patients with mucinous appendiceal adenocarcinoma(MAA).METHODS Two hundred and sixty-five patients with MAA undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy were identified from a prospective database from 2004 through 2014. All pathology was reviewed by our gastrointestinal subspecialty pathologists and histological grade was classified as well-differentiated, moderately differentiated, and poorly differentiated. Survival analysis was performed using Cox proportional hazards regression.RESULTS There were 201(75.8%) well-, 45(16.9%) moderatelyand 19(7.2%) poorly-differentiated tumors. Histological grade significantly stratified the 5-year overall survival(OS), 94%, 71% and 30% respectively(P < 0.001) as well as the 5-year disease-free survival(DFS) 66%, 21% and 0%, respectively(P < 0.001). Independent predictors of DFS included tumor grade(HR = 1.78, 95%CI: 1.21-2.63, P = 0.008), lymph node involvement(HR = 0.33, 95%CI: 0.11-0.98, P < 0.02), previous surgical score(HR = 1.31, 95%CI: 1.1-1.65, P = 0.03) and peritoneal carcinomatosis index(PCI)(HR = 1.05, 95%CI: 1.02-1.08, P = 0.002). Independent predictors of OS include tumor grade(HR = 2.79, 95%CI: 1.26-6.21, P = 0.01), PCI(HR = 1.10, 95%CI: 1.03-1.16, P = 0.002), and complete cytoreduction(HR = 0.32, 95%CI: 0.11-0.92, P = 0.03). Tumor grade and PCI were the only independent predictors of both DFS and OS. Furthermore, histological grade and lymphovascular invasion stratified the risk of lymph node metastasis into a low(6%) and high(40%) risk groups. CONCLUSION Our data demonstrates that moderately differentiated MAA have a clinical behavior and outcome that is distinct from well-and poorly-differentiated MAA. The threetier grade classification provides improved prognostic stratification and should be incorporated into patient selection and treatment algorithms. 展开更多
关键词 Hyperthermic intraperitoneal chemotherapy Pseudomyxoma peritonei HISTOLOGY grade Prognostic OUTCOMES
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Diffusion of chemically reactive species in third grade fluid flow over an exponentially stretching sheet considering magnetic field effects 被引量:2
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作者 T.Hayat M.Ijaz Khan +2 位作者 M.Waqas A.Alsaedi T.Yasmeen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第3期257-263,共7页
This article addresses the magnetohydrodynamics(MHD) flow of a third grade fluid over an exponentially stretching sheet. Analysis is carried out in the presence of first order chemical reaction. Both cases of construc... This article addresses the magnetohydrodynamics(MHD) flow of a third grade fluid over an exponentially stretching sheet. Analysis is carried out in the presence of first order chemical reaction. Both cases of constructive and destructive chemical reactions are reported. Convergent solutions of the resulting differential systems are presented in series forms. Characteristics of various sundry parameters on the velocity, concentration, skin friction and local Sherwood number are analyzed and discussed. 展开更多
关键词 Chemical reaction Third grade fluid Exponentially stretching sheet Magnetic field
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MICROSTRUCTURE OF NiCoCrAlY COMPONENT IN PLASMA SPRAYED ZrO_2/NiCoCrAlY GRADED COATING 被引量:1
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作者 Xiang, Xinghua Zhu, Jinchuan Yin, Zhongda 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第1期107-111,共5页
MICROSTRUCTUREOFNiCoCrAlYCOMPONENTINPLASMASPRAYEDZrO2/NiCoCrAlYGRADEDCOATING①XiangXinghua,ZhuJingchuan,YinZh... MICROSTRUCTUREOFNiCoCrAlYCOMPONENTINPLASMASPRAYEDZrO2/NiCoCrAlYGRADEDCOATING①XiangXinghua,ZhuJingchuan,YinZhongdaSchoolofMate... 展开更多
关键词 PLASMA SPRAYING gradeD COATING NICOCRALY MICROSTRUCTURE
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Study on the Reflection Spectra of One Dimensional Plasma Photonic Crystals Having Exponentially Graded Materials 被引量:1
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作者 S. PRASAD Vivek SINGH A. K. SINGH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第5期443-447,共5页
The transfer matrix method is used to study the effect of the permittivity profile on the reflectivity of a one dimensional plasma photonic crystal having exponentially graded material. The analysis shows that the pro... The transfer matrix method is used to study the effect of the permittivity profile on the reflectivity of a one dimensional plasma photonic crystal having exponentially graded material. The analysis shows that the proposed structure works as a perfect mirror within a certain frequency range. These frequency ranges can be completely controlled by the permittivity profile of a graded dielectric layer. As expected we observed that these frequency ranges are also controlled by plasma parameters. 展开更多
关键词 graded dielectric layer plasma photonic crystal REFLECTIVITY transfer matrixmethod
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刮痧改善腰椎间盘突出疼痛症状的系统评价及GRADE证据质量评价
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作者 高玉洁 王佳怡 +4 位作者 葛浩天 徐桂华 杨敏 姜荣荣 陈华 《世界科学技术-中医药现代化》 CSCD 北大核心 2024年第2期419-428,共10页
目的系统评价刮痧干预腰椎间盘突出疼痛症状的疗效与安全性,为其临床治疗提供循证依据。方法计算机检索自建库到2022年8月29日前公开发表在中国知网、万方、维普、中国生物医学文献服务系统、PubMed、Embase、Web of Science、The Cochr... 目的系统评价刮痧干预腰椎间盘突出疼痛症状的疗效与安全性,为其临床治疗提供循证依据。方法计算机检索自建库到2022年8月29日前公开发表在中国知网、万方、维普、中国生物医学文献服务系统、PubMed、Embase、Web of Science、The Cochrane Library数据库,收集关于刮痧干预腰椎间盘突出的随机对照试验(Randomized controlled trial,RCT)。文章由两名研究者独立筛选,根据Cochrane Reviewers Handbook 6.2的偏倚风险评估工具对纳入文献进行质量评价,应用RevMan 5.4软件对纳入文献的结局指标进行Meta分析,并采用GRADE系统对结局指标进行证据质量等级评价。结果最终纳入10篇RCT,共1087例患者。Meta分析结果显示:刮痧试验组治疗腰椎间盘突出患者在疼痛VAS评分[MD=-1.11,95%CI(-1.58,-0.64),P<0.00001]、日本骨科协会(JOA)评分[MD=4.47,95%CI(3.76,5.17),P<0.00001]、临床有效率[relative risk(RR)=1.13,95%CI(1.08,1.19),P<0.00001]和护理满意度[RR=1.21,95%CI(1.09,1.34),P=0.0005]方面,明显优于对照组,差异均有统计学意义(P<0.00001)。本文结局指标的证据质量为极低。结论当前证据表明,刮痧治疗腰椎间盘突出患者的疼痛症状具有良好临床疗效,并有助于提高临床护理满意度。由于部分结局证据质量较低,有待严谨的多中心、大样本随机对照试验来进一步验证其有效性,提升临床证据。 展开更多
关键词 刮痧 腰椎间盘突出 系统评价 META分析 grade
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Beneficiation of a low grade limestone sample 被引量:1
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作者 Rao Danda Srinivas Vijayakumar Tadiparthi Venkata +2 位作者 Subba Rao Sripada Bhaskar Raju Guntamadugu Prabhakar Swarna 《Mining Science and Technology》 EI CAS 2011年第5期631-636,共6页
Pilot scale column flotation studies were conducted on a low grade siliceous limestone ore. Silica content was reduced to less than 13g in the concentrate so that it became satisfactory for use in the paper or rubber ... Pilot scale column flotation studies were conducted on a low grade siliceous limestone ore. Silica content was reduced to less than 13g in the concentrate so that it became satisfactory for use in the paper or rubber industries. The limestone sample was crystalline and constituted primarily of calcite that contained quartz, feldspar, pyroxene, and biotite as gangue minerals. Quartz is the major silicate gangue whereas feldspar, pyroxene, and biotite exist in minor to trace quantities. Traces of pyrite were also observed within the sample. A reverse flotation process was adopted where the silicate gangue minerals were floated using two different commercial cationic collectors: Chem-750 F or Floatamine-D. The studies clearly suggest it is possible to produce a limestone concentrate assaying around 96-97% CaCO3 containing less than 1 % Si02. The effect of feed flow rate, percent solids, froth depth, and wash water on the grade and recovery of the CaC03 concentrate is discussed. 展开更多
关键词 Low grade limestoneReverse flotationColumn flotationCationic collector
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穴位埋线治疗功能性便秘疗效与安全性Meta分析及GRADE评价
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作者 胡露楠 林梦莹 +6 位作者 林湖灿 杨正宁 黄雅滢 杨欣怡 刘启鸿 任彦 柯晓 《山西中医药大学学报》 2024年第5期480-489,共10页
目的:系统评价穴位埋线治疗功能性便秘(FC)的疗效和安全性及纳入证据的质量,以期为临床决策提供循证医学证据。方法:检索中国知网(CNKI)、万方知识服务平台(WANFANG)、维普中文期刊数据库(VIP)、中国生物医学文献服务系统(SinoMed)、Emb... 目的:系统评价穴位埋线治疗功能性便秘(FC)的疗效和安全性及纳入证据的质量,以期为临床决策提供循证医学证据。方法:检索中国知网(CNKI)、万方知识服务平台(WANFANG)、维普中文期刊数据库(VIP)、中国生物医学文献服务系统(SinoMed)、Embase、PubMed和Cochrane Library数据库,搜集穴位埋线治疗FC的随机对照试验(RCT),检索时间均从建库至2023年10月16日。由2名研究者独立完成文献筛选、资料提取及偏倚风险评估,采用RevMan 5.4软件进行Meta分析,并采用GRADE评价方法对各项结局指标进行证据质量评价。结果:最终共纳入19项RCT,包括1673例患者。Meta分析结果显示,与对照组比较,穴位埋线治疗FC可提高总有效率[RR=1.23,95%CI=(1.17,1.29),P<0.00001],增加完全自发排便(CSBM)次数[MD=0.61,95%CI=(0.11,1.10),P=0.02],改善粪便性状[MD=0.53,95%CI=(0.31,0.76),P<0.00001]及排便困难[MD=-0.71,95%CI=(-1.03,-0.40),P<0.00001],缩短排便时间[MD=-0.50,95%CI=(-0.72,-0.29),P<0.00001],改善便秘生活质量评估量表(PAC-QOL)评分[MD=-7.72,95%CI=(-12.83,-2.61),P<0.003];两组不良反应发生率比较,差异无统计学意义[RR=0.37,95%CI=(0.10,1.38),P=0.14]。GRADE证据级别评价结果显示:总有效率为中级别证据质量,不良反应发生率、粪便性状评分、排便困难评分为低级别证据质量,CSBM次数、排便时间、PACQOL评分为极低级别证据质量。结论:穴位埋线治疗FC具有一定的疗效,可改善便秘相关症状,且未增加不良反应发生率。但纳入研究质量总体偏低,上述结论尚需开展更多高质量的研究予以验证。 展开更多
关键词 功能性便秘 穴位埋线 随机对照试验 META分析 grade评价
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腕踝针干预术后疼痛疗效的Meta分析和Grade评价 被引量:1
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作者 于明珠 赵丹娜 +3 位作者 杨艾影 喻悦 李鑫滟 朱宇 《军事护理》 CSCD 北大核心 2024年第5期101-106,114,共7页
目的运用循证医学方法对腕踝针干预术后疼痛的疗效和安全性进行系统评价和Grade评价。方法计算机检索中国知网、万方、维普、中国生物医学文献数据库、PubMed、Embase、Web of Science、Cochrane Library中关于腕踝针干预术后疼痛的随... 目的运用循证医学方法对腕踝针干预术后疼痛的疗效和安全性进行系统评价和Grade评价。方法计算机检索中国知网、万方、维普、中国生物医学文献数据库、PubMed、Embase、Web of Science、Cochrane Library中关于腕踝针干预术后疼痛的随机对照试验,检索时限为建库至2023年10月。采用RevMan 5.4软件进行Meta分析。结果纳入23篇文献,共计1968例患者,Meta分析结果显示,与常规治疗相比,腕踝针能够提高术后疼痛患者的总有效率[OR=4.42,95%CI(2.60,7.50),P<0.001],术后镇痛泵药量使用减少[MD=-9.03,95%CI(-12.09,-5.98),P<0.001],术后疼痛评分降低[MD=-1.39,95%CI(-1.68,-1.09),P<0.001],可减少不良反应发生率[RR=0.40,95%CI(0.32,0.48),P<0.001]以及临床满意度[OR=3.94,95%CI(2.40,6.48),P<0.001]。Grade证据分级结果显示:总有效率、不良反应发生率和临床满意度3项结局指标为中等质量证据,VAS评分指标为低质量证据,镇痛泵药量使用指标为极低质量证据。结论腕踝针可提高总有效率,减少术后镇痛药用量,不良反应少,安全性高,为患者提供了一种安全有效的镇痛方式。 展开更多
关键词 腕踝针 术后疼痛 META分析 grade评价
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乌梅丸加减治疗帕金森病的Meta分析及GRADE评价
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作者 蔡燕珊 文晓东 谭文澜 《云南中医中药杂志》 2024年第8期24-32,共9页
目的 系统评估乌梅丸加减治疗帕金森病(parkinson's disease, PD)的疗效和安全性。方法 计算机检索Cochrane Library、EMBASE、Web of Science、PubMed、CNKI、CBM等中英文数据库及临床试验中心,关于乌梅丸治疗PD的临床随机对照试验... 目的 系统评估乌梅丸加减治疗帕金森病(parkinson's disease, PD)的疗效和安全性。方法 计算机检索Cochrane Library、EMBASE、Web of Science、PubMed、CNKI、CBM等中英文数据库及临床试验中心,关于乌梅丸治疗PD的临床随机对照试验(randomized controlled trial, RCT),检索时限从建库至2023年4月。进行资料整理及数据提取等工作后,最终纳入8项研究,治疗组(乌梅丸)和对照组分别纳入226例。使用RevMan 5.3及stata14软件进行荟萃分析,使用GRADEpro GDT评估各项结局指标的证据质量。结果 治疗组降低PD统一评分量表(unified Parkinson's disease rating scale, UPDRS)的各项量表积分较对照组明显,其中在改善UPDRS Ⅰ、Ⅲ、Ⅳ方面具有统计学意义,结果分别为[MD=-0.769,95%CI(-1.213~-0.324),P=0.001]、[MD=-2.211,95%CI(-2.713~-1.708),P=0]、[MD=-0.526,95%CI(-1.041~-0.012),P=0.045]。2组在改善UPDRS总分方面差异无统计学意义[MD=3.964,95%CI(-9.465~17.392),P=0.563]。治疗组能显著提高治疗有效率,差异具有统计学意义[RR=1.709,95%CI(1.361~2.145),P=0]。各项研究均未发现不良事件发生及与治疗有关的检验指标异常。GRADE证据质量分级结果为UPDRS Ⅰ、UPDRS Ⅲ、UPDRS Ⅳ及有效率方面均为中等级别,UPDRS Ⅱ为低等级,UPDRS总分为非常低。结论 乌梅丸加减的应用对PD的治疗有一定效果,且具有良好的安全性。 展开更多
关键词 乌梅丸 帕金森病 META分析 grade评价
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Asymmetric Green's functions for exponentially graded transversely isotropic substrate–coating system
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作者 F.Akbari A.Khojasteh M.Rahimian 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期169-184,共16页
By virtue of a complete set of two displacement potentials,an analytical derivation of the elastostatic Green’s functions of an exponentially graded transversely isotropic substrate–coating system is presented.Three... By virtue of a complete set of two displacement potentials,an analytical derivation of the elastostatic Green’s functions of an exponentially graded transversely isotropic substrate–coating system is presented.Three-dimensional point–load and patch–load Green’s functions for stresses and displacements are given in line-integral representations.The formulation includes a complete set of transformed stress–potential and displacement–potential relations,with utilizing Fourier series and Hankel transforms.As illustrations,the present Green’s functions are degenerated to the special cases such as an exponentially graded half-space and a homogeneous two-layered half-space Green’s functions.Because of complicated integrand functions,the integrals are evaluated numerically and for numerical computation of the integrals,a robust and effective methodology is laid out which gives the necessary account of the presence of singularities of integration.Comparisons of the existing numerical solutions for homogeneous two-layered isotropic and transversely isotropic half-spaces are made to confirm the accuracy of the present solutions.Some typical numerical examples are also given to show the general features of the exponentially graded two-layered half-space Green’s functions that the effect of degree of variation of material properties will be recognized. 展开更多
关键词 functionally graded material transversely isotropic BI-MATERIAL Green’s function coating-substrate displacement potential
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医院药学指南制定中的证据与推荐意见GRADE系统评级方法及应用
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作者 叶志康 翟所迪 《中国医院用药评价与分析》 2024年第7期769-773,共5页
目前,国际上存在多种证据与推荐意见分级系统,对临床医务工作者阅读指南证据和推荐意见造成困扰。证据推荐分级的评估、制定与评价(GRADE)系统目前是全球使用最为广泛的证据与推荐意见分级系统,本文简单地介绍GRADE系统证据质量评级及... 目前,国际上存在多种证据与推荐意见分级系统,对临床医务工作者阅读指南证据和推荐意见造成困扰。证据推荐分级的评估、制定与评价(GRADE)系统目前是全球使用最为广泛的证据与推荐意见分级系统,本文简单地介绍GRADE系统证据质量评级及影响推荐意见形成的4个主要因素,并结合中国医院药学界发起制定的、在国际上发表的几部药学指南举例阐述,以帮助临床医务工作者了解GRADE系统,以批判性思维运用指南证据和推荐意见指导临床实践行为。 展开更多
关键词 临床指南 证据 推荐意见 grade
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参芪扶正注射液辅助治疗慢性阻塞性肺疾病的Meta分析与GRADE评价
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作者 黄武祯 陈斯宁 +4 位作者 黎展华 黄海月 张莞芬 黄丹炫 蒙建华 《科学技术与工程》 北大核心 2024年第29期12479-12487,共9页
为了系统评价参芪扶正注射液联合常规治疗作为干预措施对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的临床疗效和安全性。检索中国国家知识基础设施(China national knowledge infrastructure,CNKI)、PubMed、... 为了系统评价参芪扶正注射液联合常规治疗作为干预措施对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的临床疗效和安全性。检索中国国家知识基础设施(China national knowledge infrastructure,CNKI)、PubMed、万方数据知识服务平台(Wanfang Data)、维普中文科技期刊数据库(Weipu China science and technology journal database,VIP)等数据库,筛选并纳入2023年6月18日以前发表的参芪扶正注射液联合常规疗法治疗COPD患者的随机对照试验(randomized controlled trials,RCT),采用Cochrane风险评价工具及评估、发展和评价建议分级(grading of recommendations assessment,development and evaluation,GRADE)系统进行文献证据质量评价,用RevMan 5.4软件对临床疗效及安全性指标进行Meta分析。结果表明,共纳入16项RCTs,1 486例患者。Meta分析结果显示,参芪扶正注射液辅助治疗可提高患者总有效率和第1秒用力呼气容积/用力肺活量比值(forced expiratory volume in one second/forced vital capacity,FEV1/FVC)指标,与对照组相比具有优势(P<0.000 01、P<0.000 1);不良反应少,无严重不良反应(adverse drug reactions,ADR),两组对比无统计学差异(P=0.32);GRADE评价结果显示,有效率及不良反应指标的证据质量均为中等级,肺功能为低等级。可见参芪扶正注射辅助治疗COPD可以提高患者临床疗效,改善肺功能,且具有良好的安全性。但所纳入研究具有局限性,证据质量不高,仍需结合中药辨证使用特点,规范实验方案,开展更多的高质量RCT研究。 展开更多
关键词 参芪扶正注射 慢性阻塞性肺疾病 随机对照试验 META分析 grade评价
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火针治疗神经性皮炎的Meta分析及GRADE证据质量评价 被引量:1
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作者 姚松领 陈小艳 +3 位作者 闫小宁 金莉娜 冯莹 王佳 《中国美容医学》 CAS 2024年第8期81-87,共7页
目的:运用Meta分析系统评价火针治疗神经性皮炎的临床疗效。方法:计算机检索中国期刊全文数据库(CNKI)、重庆维普(VIP)、万方数据库(WanFang)、中国生物医学文献数据库(CBM)及Pubmed、Cochrane library等中英文数据库,时限设定为建库-2... 目的:运用Meta分析系统评价火针治疗神经性皮炎的临床疗效。方法:计算机检索中国期刊全文数据库(CNKI)、重庆维普(VIP)、万方数据库(WanFang)、中国生物医学文献数据库(CBM)及Pubmed、Cochrane library等中英文数据库,时限设定为建库-2023年2月28日,检索火针治疗神经性皮炎的随机对照试验(Randomized controlled,RCT)相关文献。运用Cochrane风险偏倚评估工具对纳入研究的文献质量评估,再运用Revman5.4软件进行Meta分析,运用TSA0.9.5.10软件进行试验序贯分析,使用GRADE软件对主要结局指标的证据进行证据质量评级。结果:①共纳入18篇研究,1 662例患者,火针组840例,对照组822例;②Meta分析结果显示:火针组的临床有效率[OR=3.99,95%CI(2.81,5.68),Z=7.71,P<0.00 001]、复发率[OR=0.27,95%CI(0.11,0.68),Z=2.79,P=0.005)]均优于对照组;症状积分[MD=-1.49,95%CI(-2.25,-0.73),Z=3.85,P=0.0 001]、TNF-α水平[MD=-4.26,95%CI(-7.01,-1.51),Z=3.03,P=0.002]、IL-6水平[MD=-7.39,95%CI(-14.36,-0.42),Z=2.08,P=0.04]、IL-4水平[MD=-1.50,95%CI(-1.94,-1.06),Z=6.69,P<0.00 001]方面火针组均低于对照组;③火针组不良反应率整体低于对照组;④试验序贯分析显示:累计Z值穿过了传统界值和TSA界值,表示虽然累计的信息量未达到期望值,但不需要更多的试验,提前得到肯定的结论,结果较为可靠。结论:火针治疗神经性皮炎的具有明确的疗效,在症状积分和TNF-α、IL-6、IL-4水平表达等方面效果均优于对照组,安全性也较高,可为中医外治法治疗神经性皮炎的有效性提供相关证据。但因GRADE证据质量评级显示证据质量不理想,建议后续医务工作者可减少开展火针治疗神经性皮炎相关低质量试验,开展一些多中心、高质量的研究对结果加以佐证,从而避免科研和医疗资源的浪费。 展开更多
关键词 神经性皮炎 火针 META分析 序贯分析 grade评价
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Free vibration characteristics of sectioned unidirectional/bidirectional functionally graded material cantilever beams based on finite element analysis
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作者 N.V.VIET W.ZAKI Quan WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第12期1787-1804,共18页
Advancements in manufacturing technology,including the rapid development of additive manufacturing(AM),allow the fabrication of complex functionally graded material(FGM)sectioned beams.Portions of these beams may be m... Advancements in manufacturing technology,including the rapid development of additive manufacturing(AM),allow the fabrication of complex functionally graded material(FGM)sectioned beams.Portions of these beams may be made from different materials with possibly different gradients of material properties.The present work proposes models to investigate the free vibration of FGM sectioned beams based on onedimensional(1D)finite element analysis.For this purpose,a sample beam is divided into discrete elements,and the total energy stored in each element during vibration is computed by considering either the Timoshenko or Euler-Bernoulli beam theory.Then,Hamilton’s principle is used to derive the equations of motion for the beam.The effects of material properties and dimensions of FGM sections on the beam’s natural frequencies and their corresponding mode shapes are then investigated based on a dynamic Timoshenko model(TM).The presented model is validated by comparison with three-dimensional(3D)finite element simulations of the first three mode shapes of the beam. 展开更多
关键词 finite element model(FEM) DYNAMICS functionally graded material(FGM) Timoshenko beam theory
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