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Maximum likelihood estimation of nonlinear mixed-effects models with crossed random effects by combining first-order conditional linearization and sequential quadratic programming
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作者 Liyong Fu Mingliang Wang +2 位作者 Zuoheng Wang Xinyu Song Shouzheng Tang 《生物数学学报:英文版》 2019年第5期1-18,共18页
Nonlinear mixed-eirects (NLME) modek have become popular in various disciplines over the past several decades.However,the existing methods for parameter estimation imple-mented in standard statistical packages such as... Nonlinear mixed-eirects (NLME) modek have become popular in various disciplines over the past several decades.However,the existing methods for parameter estimation imple-mented in standard statistical packages such as SAS and R/S-Plus are generally limited k) single-or multi-level NLME models that only allow nested random effects and are unable to cope with crossed random effects within the framework of NLME modeling.In t his study,wc propose a general formulation of NLME models that can accommodate both nested and crassed random effects,and then develop a computational algorit hm for parameter estimation based on normal assumptions.The maximum likelihood estimation is carried out using the first-order conditional expansion (FOCE) for NLME model linearization and sequential quadratic programming (SCJP) for computational optimization while ensuring positive-definiteness of the estimated variance-covariance matrices of both random effects and error terms.The FOCE-SQP algorithm is evaluated using the height and diameter data measured on trees from Korean larch (L.olgeiisis var,Chang-paienA.b) experimental plots aa well as simulation studies.We show that the FOCE-SQP method converges fast with high accuracy.Applications of the general formulation of NLME models are illustrated with an analysis of the Korean larch data. 展开更多
关键词 CROSSED RANDOM EFFECTS FIRST-ORDER CONDITIONAL expansion nested RANDOM EFFECTS NONLINEAR mixed-effects models sequential quadratic programming
SOME PROBLEMS IN RADIATION TRANSPORT FLUID MECHANICS AND QUANTUM FLUID MECHANICS
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作者 Boling Guo Jun Wu 《应用数学年刊:英文版》 2019年第2期111-125,共15页
We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport flu... We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport fluid mechanics equations under certain initial and boundary values. In addition, we also obtain the periodic region problem of the compressible N-S equation with quantum effect has weak solutions under some conditions. 展开更多
关键词 RADIATION transport equation RADIATION FLUID MECHANICS EQUATIONS FLUID MECHANICS EQUATIONS with QUANTUM effects
护理实训教学中关爱能力以及沟通技巧培养方法
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作者 邓奕 《智慧健康》 2019年第21期37-38,共2页
目的分析在护理实训教学之中加强对关爱能力、沟通技巧方面的培养和学习,对临床护理产生的影响。方法选取2016年11月至2018年11月于本校就读护生中盲选200例纳入本次研究中,按照护生培训时间先后进行分组纳入。常规组100名护生接受常规... 目的分析在护理实训教学之中加强对关爱能力、沟通技巧方面的培养和学习,对临床护理产生的影响。方法选取2016年11月至2018年11月于本校就读护生中盲选200例纳入本次研究中,按照护生培训时间先后进行分组纳入。常规组100名护生接受常规培训,实验组100名护生在实训教学之中加强了关爱能力和沟通技巧方面的培训,对两组护生的护理满意度评分、沟通能力评分以及操作成绩展开分析和对比。结果实验组在本次研究中护生对于护理培训满意度明显优于常规组,组别对比间有显著差异(P<0.05)。实验组在本次研究中护生操作成绩明显优于高规组,组别对比间有显著差异(P<0.05)。实验组在本次研究中护生沟通能力评分明显优于常规组,组别对比间有显著差异(P<0.05)。结论在护理实训教学之中加强了关爱能力、沟通技巧方面的培训,可进一步保障护生的临床教学效果,可有效的解决临床中出现的实际问题,这种教学方式提升护理的人文关怀,加强护患之间的沟通能力,值得推广。 展开更多
关键词 沟通技巧 关爱能力 护理实训教学 效果
Genome wide association study identifies SNPs associated with fatty acid composition in Chinese Wagyu cattle 预览
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作者 Zezhao Wang Bo Zhu +10 位作者 Hong Niu Wengang Zhang Ling Xu Lei Xu Yan Chen Lupei Zhang Xue Gao Huijiang Gao Shengli Zhang Lingyang Xu Junya Li 《畜牧与生物技术杂志:英文版》 SCIE CAS CSCD 2019年第2期353-364,共12页
Background: Fatty acids are important traits that affect meat quality and nutritive values in beef cattle. Detection of genetic variants for fatty acid composition can help to elucidate the genetic mechanism underpinn... Background: Fatty acids are important traits that affect meat quality and nutritive values in beef cattle. Detection of genetic variants for fatty acid composition can help to elucidate the genetic mechanism underpinning these traits and promote the improvement of fatty acid profiles. In this study, we performed a genome-wide association study(GWAS) on fatty acid composition using high-density single nucleotide polymorphism(SNP) arrays in Chinese Wagyu cattle.Results: In total, we detected 15 and 8 significant genome-wide SNPs for individual fatty acids and fatty acid groups in Chinese Wagyu cattle, respectively. Also, we identified nine candidate genes based on 100 kb regions around associated SNPs. Four SNPs significantly associated with C14:1 cis-9 were embedded with stearoyl-CoA desaturase(SCD), while three SNPs in total were identified for C22:6 n-3 within Phospholipid scramblase family member 5(PLSCR5), Cytoplasmic linker associated protein 1(CLASP1), and Chymosin(CYM). Notably, we found the top candidate SNP within SCD can explain ~ 7.37% of phenotypic variance for C14:1 cis-9.Moreover, we detected several blocks with high LD in the 100 kb region around SCD. In addition, we found three significant SNPs within a 100 kb region showing pleiotropic effects related to multiple FA groups(PUFA,n-6, and PUFA/SFA), which contains BAI1 associated protein 2 like 2(BAIAP2 L2), MAF bZIP transcription factor F(MAFF),and transmembrane protein 184 B(TMEM184 B).Conclusions: Our study identified several significant SNPs and candidate genes for individual fatty acids and fatty acid groups in Chinese Wagyu cattle, and these findings will further assist the design of breeding programs for meat quality in cattle. 展开更多
关键词 CHINESE WAGYU CATTLE Fatty acids GWAS MEAT quality PLEIOTROPIC effects
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嘉峪关市其他感染性腹泻与气象相关影响因素研究
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作者 李世雄 王玉明 董继元 《中国公共卫生管理》 2019年第2期157-159,共3页
目的研究其他感染性腹泻发病与气象因素的关联性,分析不同气象因素对其他感染性腹泻的影响及其滞后效应,为调整防控措施提供科学依据。方法利用嘉峪关市2008—2016年其他感染性腹泻发病人数,结合同期气象资料,包括气温、气压、相对湿度... 目的研究其他感染性腹泻发病与气象因素的关联性,分析不同气象因素对其他感染性腹泻的影响及其滞后效应,为调整防控措施提供科学依据。方法利用嘉峪关市2008—2016年其他感染性腹泻发病人数,结合同期气象资料,包括气温、气压、相对湿度、风速等,用广义相加模型结合分布滞后非线性模型探讨不同气象指标对其他感染性腹泻发病的影响。结果嘉峪关市其他感染性腹泻发病时间分布呈明显的季节周期性变化,6—8月出现高峰,其余月份发病例数较少;气象因素在不同滞后日与其他感染性腹泻的关联呈非线性,气温与其他感染性腹泻的风险效应呈正向关联,以日均气温8.50℃为参照,气温为33℃、滞后14d时RR值最高,为7.73(P<0.01)。风速和相对湿度与其他感染性腹泻的风险效应呈负向关联,滞后0d时RR值的95%CI下限均小于1,无统计学意义(P>0.05)。结论气温可能是嘉峪关市其他感染性腹泻暴发的重要原因之一,对其他感染性腹泻在人群中的发生和流行发挥重要作用,通过改善居民生活习惯与易感人群自身体质,可间接影响其他感染性腹泻在人群中的分布。 展开更多
关键词 气象因素 其他感染性腹泻 滞后 效应
栽培措施对广元油橄榄结果率的影响研究 预览 被引量:1
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作者 唐巍 陈庆洲 +1 位作者 漆明生 吴浩 《林业调查规划》 2019年第1期163-165,共3页
利用3626块标准样地调查材料,采用线性模型和数量化理论Ⅰ等分析手段,硏究栽培措施对广元油橄榄结果率的影响。结果表明,广元油橄榄结果率除受林龄影响外,还受品种选择、施肥、修枝、灌溉、垒坛等栽培措施影响,在这些措施中,施肥和灌溉... 利用3626块标准样地调查材料,采用线性模型和数量化理论Ⅰ等分析手段,硏究栽培措施对广元油橄榄结果率的影响。结果表明,广元油橄榄结果率除受林龄影响外,还受品种选择、施肥、修枝、灌溉、垒坛等栽培措施影响,在这些措施中,施肥和灌溉能提高油橄榄的结果率,修枝和垒坛则会降低结果率;除草、松土、病虫害防治等常规应用栽培措施对结果率的影响不明显。在所选用的品种中,弗奥品种的结果率高于其他品种。 展开更多
关键词 栽培措施 油橄榄 结果率 影响 林龄 广元市
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A zinc(Ⅱ) MOF based on secondary building units of infinite wavy-shaped chain exhibiting obvious luminescent sense effects
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作者 Kai Li Kunhuan He +3 位作者 Quanwen Li Bin Xia Qinglun Wang Yinghui Zhang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期499-501,共3页
A new metal-organic framework (MOF),{[Zn7 (BPS)4 (OH)6 (H2O)2]·5 H2O]n}(1), (H2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthesized un... A new metal-organic framework (MOF),{[Zn7 (BPS)4 (OH)6 (H2O)2]·5 H2O]n}(1), (H2 BPS=4,4′-bibenzoic acid-2,2′-sulfone), based on a wavy and infinite chain-shaped secondary building units, has been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction and further confirmed by PXRD, TGA and IR spectrum. The solid-state emission spectra reveal that compound 1 presents strong luminescence emission bands at room temperature. The fluorescent properties of compound 1 in diverse organic solvents indicated that 1 has palpable luminescent sense effects for DMF and DMAC. 展开更多
关键词 METAL-ORGANIC frameworks Secondary building unit SOLID-STATE emission spectra Fluorescent properties LUMINESCENT SENSE EFFECTS
AE文字特效的技术应用与探讨 预览
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作者 李荣锦 《信息与电脑》 2019年第4期169-171,共3页
AfterEffects是影视后期合成制作中最具影响力的非线性编辑软件之一。在影视、多媒体、宣传广告设计领域中,文字效果是最常用的技术。AE有很强的文字创建功能,并能为文字添加动画特效,从而制作出创意文字效果。AE中的文字特效主要通过... AfterEffects是影视后期合成制作中最具影响力的非线性编辑软件之一。在影视、多媒体、宣传广告设计领域中,文字效果是最常用的技术。AE有很强的文字创建功能,并能为文字添加动画特效,从而制作出创意文字效果。AE中的文字特效主要通过特效插件、时间线中的路径文字和文字动画属性进行制作。笔者介绍了文字特效制作的技术和典型案例的制作,探讨了该工具在文字效果中的制作技巧。 展开更多
关键词 AE 动态文字 特效 路径
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福建省尤溪县医保支付方式改革及效果研究 预览
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作者 胡佳 朱晓丽 +1 位作者 郑英 代涛 《中国卫生政策研究》 CSCD 北大核心 2019年第5期25-31,共7页
目的:分析福建省尤溪县医保支付方式改革的措施、效果及存在问题,并提出建议。方法:通过文献研究和现场调研进行资料收集,采用统计描述和主题框架法进行分析。结果:尤溪县通过试行医联体总额预付制、持续探索完善住院费用按病种付费制... 目的:分析福建省尤溪县医保支付方式改革的措施、效果及存在问题,并提出建议。方法:通过文献研究和现场调研进行资料收集,采用统计描述和主题框架法进行分析。结果:尤溪县通过试行医联体总额预付制、持续探索完善住院费用按病种付费制度、实行差异化支付政策以及强化医保监督管理职能等,实现了医保基金运行基本平稳、医疗费用过快增长得以控制、县域内就诊率显著提升、基层服务利用逐步增加、医院收入结构得以优化、患者就医经济负担有所减轻。结论与建议:尤溪县医保支付方式改革有利于激发医疗服务提供者内生控费和质量提升动力、引导患者合理就医、保障基金安全可持续运行,但支付标准的科学性和合理性有待提升、信息化支撑作用尚未发挥到位、病案首页质量仍难以满足需求,需进行针对性完善,并同步推进其他相关领域改革。 展开更多
关键词 总额预付制 按病种付费 效果
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Reconfigurable generation of optical vortices based on forward stimulated intermodal Brillouin scattering in subwavelength-hole photonic waveguides
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作者 Dae Seok Han Myeong Soo Kang 《光子学研究:英文版》 CSCD 2019年第7期69-76,共8页
An all-optically reconfigurable generation of optical vortices would be highly beneficial to the implementation of next-generation optical communication and advanced information processing. The previously demonstrated... An all-optically reconfigurable generation of optical vortices would be highly beneficial to the implementation of next-generation optical communication and advanced information processing. The previously demonstrated approaches based on the parametric nonlinear optical processes, however, have exhibited limited conversion efficiency due to the group velocity mismatch and nonlinear phase shifts, and require the cumbersome preparation of either the optical element or initial seed beam having a non-zero topological charge. Here, we propose and analyze a novel scheme for highly efficient all-optical generation and control of optical vortices based on the dynamic acoustic vortex grating created by forward stimulated intermodal Brillouin scattering in a subwavelength-hole photonic waveguide. The dual-frequency pump beams in two different hybrid optical modes drive an acoustic vortex mode, which transforms a signal in the fundamental optical mode into an optical vortex mode. This scheme not only eliminates the need for the initial preparation of an angular-momentum-carrying medium or an optical vortex seed but also guarantees high modal purity and nearly 100% conversion efficiency assisted by the energymomentum conservation. We also investigate the feasibility and practicability of the subwavelength-hole waveguides by examining the intermodal conversion efficiency and robustness of guidance of the optical vortices,taking into account the impact of the Kerr-type nonlinear effects on the intermodal Brillouin interactions based on our rigorous full-vectorial analytical theory. 展开更多
关键词 RECONFIGURABLE generation WAVEGUIDES effects
早期应用产后康复治疗仪促进产褥期妇女康复的效果观察 预览
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作者 晋水红 曾嘉璐 《中医临床研究》 2019年第5期114-116,共3页
目的:探究对产褥期妇女早期应用产后康复治疗仪的效果,为临床提供指导。方法:随机将2015年2月-2018年3月我院86例产褥期妇女分为对照组(43例,应用常规干预)、实验组(43例,在常规干预的基础上应用产后康复治疗仪)。研究对比实验组和对照... 目的:探究对产褥期妇女早期应用产后康复治疗仪的效果,为临床提供指导。方法:随机将2015年2月-2018年3月我院86例产褥期妇女分为对照组(43例,应用常规干预)、实验组(43例,在常规干预的基础上应用产后康复治疗仪)。研究对比实验组和对照组妇女的泌乳情况、子宫底高度及泌乳始动时间。结果:实验组妇女泌乳情况相比对照组明显更优,且平均泌乳量(29.24±5.61)mL相比对照组(19.24±7.60)mL明显更多,P<0.05;实验组妇女产后24h、48h、72h子宫底高度分别为(20.16±2.61)cm、(12.24±1.69)cm、(6.32±0.85)cm,相比对照组[(22.24±1.89)cm、(16.24±1.36)cm、(7.79±0.69)cm]明显更低,P<0.05;实验组妇女泌乳始动时间相比对照组明显更优,且平均泌乳始动时间[(25.16±6.35)h]相比对照组[(42.13±8.89)h]明显更少,P<0.05。结论:对产褥期妇女早期应用产后康复治疗仪的效果更佳,有助于改善产后妇女泌乳情况。 展开更多
关键词 产褥期 早期 产后康复治疗仪 效果
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清丰县主要气象灾害及防灾减灾措施 预览
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作者 秦政 《农业灾害研究》 2019年第3期110-111,共2页
对清丰县主要气象灾害类型及危害进行分析,从提升灾害性天气监测预警水平、建立联合防灾减灾机制、加强气象防灾减灾科普教育3个方面提出了科学有效的防灾减灾措施。
关键词 清丰县 气象灾害 影响 防灾减灾
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神经节苷脂对患儿神经损伤功能康复的作用 预览
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作者 袁作芬 柳开典 冉珍梅 《中国继续医学教育》 2019年第25期149-152,共4页
目的探讨分析神经节苷脂在神经损伤后患儿功能康复中的应用。方法选取80 例神经损伤患儿,随机分为观察组和对照组。两组均接受康复训练,观察组同时接受神经节苷脂进行治疗。对比分析两组患儿的生活能力、运动能力、临床疗效和患儿家属... 目的探讨分析神经节苷脂在神经损伤后患儿功能康复中的应用。方法选取80 例神经损伤患儿,随机分为观察组和对照组。两组均接受康复训练,观察组同时接受神经节苷脂进行治疗。对比分析两组患儿的生活能力、运动能力、临床疗效和患儿家属满意度。结果治疗后,观察组生活能力评分,运动能力评分和对照组相比效果显著,差异有统计学意义。治疗后,观察组总有效率为97.50%(39/40)明显优于对照组80.0%(32/40),差异有统计学意义。观察组患儿家属满意度评分为(94.17±2.88)分明显高于对照组(83.19±2.74)分,差异有统计学意义。两组患儿均无明显不良反应发生。结论神经节苷脂结合常规方法治疗神经损伤后患儿,能够有效提高患儿的临床疗效,改善患儿的生活能力与运动能力,同时提高了了患儿家属的满意度。 展开更多
关键词 神经节苷脂 神经损伤 康复训练 神经功能 恢复 影响
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Anti-inflammatory Effects of Volatile Oil of Ocimum basilicum L. in Bozhou and Its Mechanisms 预览
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作者 Jie WANG Xing ZHANG Qun CHEN 《药用植物研究(英文版)》 2019年第4期34-36,43共4页
[Objectives] The research aimed to study the anti-inflammatory effects of volatile oil from Ocimum basilicum L. in Bozhou through the experimental animal model of inflammation.[Methods] Xylene-induced mouse ear swelli... [Objectives] The research aimed to study the anti-inflammatory effects of volatile oil from Ocimum basilicum L. in Bozhou through the experimental animal model of inflammation.[Methods] Xylene-induced mouse ear swelling model and carrageenan-induced mouse paw swelling model were used to compare the anti-inflammatory effects of volatile oil from O. basilicum L.[Results] The extremely high, high, medium, and low doses of volatile oil from O. basilicum L. had a certain inhibitory effect on the ear swelling of mice induced by xylene ( P <0.05), and the inhibitory effect of high-dose group on the ear swelling of mice was better. The swollen degree of the mice s toes in the different dose groups of volatile oil from O. basilicum L. was significantly lower ( P <0.05), and the high-dose and middle-dose groups had better inhibition.[Conclusions] The volatile oil from O. basilicum L. in Bozhou had a significant inhibitory effect on xylene-induced mouse ear swelling and carrageenan-induced mouse paw swelling. It proved and clarified the anti-inflammatory effects of volatile oil from O. basilicum L. in Bozhou. 展开更多
关键词 Bozhou OCIMUM basilicum L. VOLATILE OIL ANTI-INFLAMMATORY EFFECTS
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概述环境化学对人体内脏影响 预览
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作者 关明铭 《当代化工研究》 2019年第3期28-29,共2页
环境是人类赖以生存发展的前提和基础,“保护环境,人人有责”已深入民心,但是能真正做到是非常坚难的,是需要全民、全球一起努力的。随着经济发展,人们生活水平的提高,环境污染也越来越严重,全球变暖、雾霾等问题已成为全球都面临的重... 环境是人类赖以生存发展的前提和基础,“保护环境,人人有责”已深入民心,但是能真正做到是非常坚难的,是需要全民、全球一起努力的。随着经济发展,人们生活水平的提高,环境污染也越来越严重,全球变暖、雾霾等问题已成为全球都面临的重要难关,造成环境污染因素中化学物质引起的污染约为80%-90%。环境化学即是从化学的角度出发,研究环境中天然的和人为释放的化学物质的迁移转化规律,及其与环境质量、人体健康的关系。如:随着经济的发展,汽车已走入千家万户,但是汽车所排放的尾气对环境具有极大的污染。环境的污染直接影响着人类的身体健康,甚至严重的还会影响到人们的生命安全。如:天气突变或换季就极易引起流行性感冒。所以我们要高度重视环境污染问题,抓好预防工作,正确分析环境因素对人类健康的影响,防止疾病的发生。本文对环境化学对人体内脏影响进行具体分析。 展开更多
关键词 环境化学 人体内脏 因素 影响 措施
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孟鲁司特钠治疗小儿哮喘临床效果分析 预览
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作者 卢文强 《中国继续医学教育》 2019年第28期125-127,共3页
目的分析孟鲁司特钠治疗小儿哮喘临床效果、复发及不良反应。方法选择本院2015年5月—2018年5月收治的小儿哮喘患者作为研究对象,一共80例,随机分组,各组为40例,对照组给予常规治疗,观察组在常规治疗的前提下,结合白三烯受体拮抗剂孟鲁... 目的分析孟鲁司特钠治疗小儿哮喘临床效果、复发及不良反应。方法选择本院2015年5月—2018年5月收治的小儿哮喘患者作为研究对象,一共80例,随机分组,各组为40例,对照组给予常规治疗,观察组在常规治疗的前提下,结合白三烯受体拮抗剂孟鲁司特钠,治疗两周后比较两组患者的治疗疗效、复发情况、不良反应。结果(1)观察组治疗有效率明显高于对照组,P<0.05。(2)观察组复发率为2.50%,对照组复发率为25.00%,观察组复发率明显低于对照组,P<0.05。同时,观察组症状缓解时间和肺部症状结束时间明显比对照组更短,P<0.05。(3)观察组不良反应率明显低于对照组,P<0.05。结论孟鲁司特钠治疗小儿哮喘的疗效确切。 展开更多
关键词 孟鲁司特钠 治疗 小儿哮喘 效果 复发 不良反应
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眼外伤早期继发青光眼患者进行对症治疗的临床效果评价
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作者 杨学秋 丁伟娜 《智慧健康》 2019年第21期64-65,共2页
目的研究对眼外伤早期继发青光眼采用对症治疗的效果。方法纳入我院于2017年8月至2018年8月收治的70例眼外伤早期继发青光眼患者,所有患者均进行对症治疗,研究对症治疗的临床效果。结果治疗后患者的平均眼压得到显著改善,治疗前(41.98&#... 目的研究对眼外伤早期继发青光眼采用对症治疗的效果。方法纳入我院于2017年8月至2018年8月收治的70例眼外伤早期继发青光眼患者,所有患者均进行对症治疗,研究对症治疗的临床效果。结果治疗后患者的平均眼压得到显著改善,治疗前(41.98±3.25)mmHg,治疗后(17.26±1.31)mmHg的眼压对比(P<0.05),存在统计学意义。有2例患者治疗后的眼压高(发生率为2.86%)。其余68例患者的眼压经过治疗均控制在21mmHg之内(发生率97.14%)。结论对眼外伤早期继发青光眼采用对症治疗的效果显著,能够缓解患者的眼压情况,促进患者的快速康复,可以在临床上予以推广使用。 展开更多
关键词 眼外伤 早期继发青光眼 对症治疗 效果
An Experimental Phonetic Study of Dialectal Impact on English Learners'Prosody--A Case Study of Shandong Dialect 预览
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作者 WANG Pei-juan ZHAI Hong-hua 《文学与艺术研究:英文版》 2019年第7期675-685,共11页
It has been commonly recognized by the academic community that Chinese English learners can be regarded as the trilingual learners in dialects,Mandarin,and then English.Thus the first two acquired languages seem to be... It has been commonly recognized by the academic community that Chinese English learners can be regarded as the trilingual learners in dialects,Mandarin,and then English.Thus the first two acquired languages seem to be unavoidable to result in some effects on the study of English,especially the prosody of English.At the same time,the fact that the English prosodic research has been a significant project in the linguistic study with the globalization and localization of English,draws the public’s attention to the further study of the prosody of English for which is of vital importance in English learning.Focusing on the intonation,stress,tone,pause,and so on,prosody is the fundamental element of speech and the core of English phonetics.Taking Shandong dialect as an example,the study investigates the influence of the dialects on the learning of English prosody from two aspects—intonation and stress,by the acoustic analysis and comparison of the English prosody of linguistic data from Shandong EFL learners and English native speakers based on IViE(Intonational Variation in English)and ToBI(Tone and Breaks Indices)systems using Praat software.In addition,the reasons why these effects and problems take place are discussed profoundly.Therefore the corresponding measures should be taken in order to help students eliminate the negative impacts of their dialects and deliver standard English.The study may have great references on the improvement and elevation of teaching methods on the dialectal regions and some implications on second language acquisition. 展开更多
关键词 SHANDONG DIALECTS PROSODY INTONATION stress effects
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Review: Recent Advancement of Experimental and NumericalInvestigations for Breaking Waves 预览
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作者 Cheng Liu Yiding Hu +1 位作者 Zheng Li Decheng Wan 《哈尔滨工业大学学报:英文版》 EI CAS 2019年第5期1-16,共16页
Breaking wave is a complex physical phenomenon that takes place at the gas fluid interface which is the chief reason for the generation of two phase turbulence wave energy dissipation and mass transfer between air and... Breaking wave is a complex physical phenomenon that takes place at the gas fluid interface which is the chief reason for the generation of two phase turbulence wave energy dissipation and mass transfer between air and water. For marine hydrodynamics the breaking bow wave of high speed vessels induces the bubble mixed flow travelling around the ship eventually developing to be the turbulent wake which is easy to be detected by photoelectric equipment. Besides the flow induced noise stemming from wave plunging may weaken the acoustic stealth of water surface craft. In the oceanographic physics context wave breaking accounts for the energy and mass exchange of the ocean atmosphere system which has a great effect on the weather forecasts and global climate predictions. Due to multi scale properties of multiphase turbulent flows a wide range of time and length scales should be resolved making it rather complicated for experimental and numerical investigations. In early reviews[1-4] general mechanisms related to wave breaking problems are well described. However previous emphasis lies on the phenomenological characteristics of breaking wave. Thus this review summarizes the recent experimental and numerical advances of the studies of air entrainment bubble distribution energy dissipation capillary effect and so on. 展开更多
关键词 wave breaking energy DISSIPATION air ENTRAINMENT and VOID FRACTION BUBBLE and DROPLET size distribution capillary effects
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Mn含量对铁路货车用低温铸钢显微组织和力学性能的影响 预览
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作者 肖利民 《黑龙江科学》 2019年第18期8-11,共4页
利用金相显微镜、扫描电子显微镜、拉伸试验和冲击试验等手段,研究了0.8%~2.1%含量的Mn对铁路货车用低温铸钢显微组织和力学性能的影响。试验结果表明:不同的Mn含量下,铸钢正火后的组织均由先共析铁素体和珠光体构成,随着Mn含量的增加,... 利用金相显微镜、扫描电子显微镜、拉伸试验和冲击试验等手段,研究了0.8%~2.1%含量的Mn对铁路货车用低温铸钢显微组织和力学性能的影响。试验结果表明:不同的Mn含量下,铸钢正火后的组织均由先共析铁素体和珠光体构成,随着Mn含量的增加,珠光体含量和晶粒度等级均增加,Mn含量达到2.1%时,铸钢晶粒度等级为11.6。随着Mn含量的增加,铸钢强度逐渐升高,塑性逐渐降低,-60℃的冲击吸收功是先增加后降低。 展开更多
关键词 MN含量 铁路货车 低温铸钢 显微组织 力学性能 影响
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