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Management of an Unusual Complication of Uterine Fibroids in the Gynecological Department of the University and Hospital Center of Treichville (Cote D’ivoire): About 2 Cases of Non-Puerperal Uterine Inversion
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作者 Eric Bohoussou Lamine Dia +3 位作者 Ignace Yao Kacou Anzoua Privat Guie Simplice Anongba 《Open Journal of Obstetrics and Gynecology》 2017年第2期220-225,共6页
Uterine inversion is rare. It is classically described as a complication of the delivery period. Non-puerperal uterine inversion is exceptional and usually results from a tumor implanted on fundus of the uterus. We re... Uterine inversion is rare. It is classically described as a complication of the delivery period. Non-puerperal uterine inversion is exceptional and usually results from a tumor implanted on fundus of the uterus. We report two cases of non-puerperal uterine inversion caused by fundal submucosal myoma. Its diagnosis can be difficult and a high index of clinical suspicion is required to make a prompt diagnosis. The delayed diagnosis observed in our cases, caused uterine necrosis, which was managed by hysterectomy. The patients’ post-operative course was uneventful. 展开更多
关键词 non-Puerperal UTERINE inversion MYOMA HYSTERECTOMY
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空间结构模型优化的弹性参数FFT-MA随机建模
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作者 黄国娇 曾繁鑫 +2 位作者 王善涛 张宏兵 蒋甫玉 《石油地球物理勘探》 EI CSCD 北大核心 2024年第5期1121-1131,共11页
快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对F... 快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对FFT-MA方法的研究并未提出准确构建空间结构模型的有效方法。为此,文中提出了一种有效的空间结构模型估计方法。该方法基于反演思想,通过最小化随机模型与测井数据和地震数据的空间结构差异,分别估计空间结构模型的纵向自相关长度和横向自相关长度。同时,为了优化空间结构模型的估计效果,在纵向自相关长度的反演过程中引入边界保护正则化,以提高反演的稳定性。此外,将地震约束引入模型优选以提高随机模型的稳定性。实验结果表明:该方法能够稳定估计地下介质的非平稳空间结构模型,从而建立准确描述复杂储层非平稳空间相关特征的高分辨率随机模型。与基于序贯高斯协模拟的随机建模方法相比,使用空间结构模型优化的FFT-MA随机建模方法能够有效刻画多种复杂地质构造从而实现复杂储层建模。 展开更多
关键词 FFT-MA 方法 空间结构模型 参数反演 边界保护正则化 随机建模 非平稳性建模
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The inversion of 3-D crustal structure and hypocenter location in the Beijing-Tianjin-Tangshan-Zhangjiakou area by genetic algorithm 被引量:2
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作者 万永革 刘瑞丰 李鸿吉 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第6期74-86,共13页
This paper discusses the inversion of velocity structure and hypocenters location in the Beijing Tianjin Tangshan Zhangjiakou area by genetic algorithm. The hypocenters location of sele... This paper discusses the inversion of velocity structure and hypocenters location in the Beijing Tianjin Tangshan Zhangjiakou area by genetic algorithm. The hypocenters location of selected earthquakes and crustal structure of this area are obtained using the travel time data of local earthquakes acquired by the Telemetered Seismic Network of Northern China. The mean and standard residuals of hypocenter location acquired by this method are much less than those provided by the report of respective earthquakes. The crustal structure of the first and the second layers obtained interpret the outline of the plain and mountain area in the region successfully and the crustal structure of the third layer nearly coincides with the Moho discontinuity obtained by artificial seismic sounding. These show the genetic algorithm is effective to the inversion of hypocenter location and three dimensional velocity structure. 展开更多
关键词 genetic algorithm HYPOCENTER CRUSTAL STRUCTURE inversion non linear
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Bayesian Markov chain Monte Carlo inversion for anisotropy of PP-and PS-wave in weakly anisotropic and heterogeneous media 被引量:4
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作者 Xinpeng Pan Guangzhi Zhang Xingyao Yin 《Earthquake Science》 CSCD 2017年第1期33-46,共14页
A single set of vertically aligned cracks embedded in a purely isotropic background may be con- sidered as a long-wavelength effective transversely iso- tropy (HTI) medium with a horizontal symmetry axis. The crack-... A single set of vertically aligned cracks embedded in a purely isotropic background may be con- sidered as a long-wavelength effective transversely iso- tropy (HTI) medium with a horizontal symmetry axis. The crack-induced HTI anisotropy can be characterized by the weakly anisotropic parameters introduced by Thomsen. The seismic scattering theory can be utilized for the inversion for the anisotropic parameters in weakly aniso- tropic and heterogeneous HTI media. Based on the seismic scattering theory, we first derived the linearized PP- and PS-wave reflection coefficients in terms of P- and S-wave impedances, density as well as three anisotropic parameters in HTI media. Then, we proposed a novel Bayesian Mar- kov chain Monte Carlo inversion method of PP- and PS- wave for six elastic and anisotropic parameters directly. Tests on synthetic azimuthal seismic data contaminated by random errors demonstrated that this method appears more accurate, anti-noise and stable owing to the usage of the constrained PS-wave compared with the standards inver- sion scheme taking only the PP-wave into account. 展开更多
关键词 Crack-induced anisotropy Seismic scattering theory HTI media PP- and PS-wave - Bayesian Markov chain Monte Carlo inversion
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3D v_P and v_S models of southeastern margin of the Tibetan plateau from joint inversion of body-wave arrival times and surface-wave dispersion data 被引量:2
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作者 Lina Gao Haijiang Zhang +1 位作者 Huajian Yao Hui Huang 《Earthquake Science》 CSCD 2017年第1期17-32,共16页
A new 3D velocity model of the crust and upper mantle in the southeastern (SE) margin of the Tibetan plateau was obtained by joint inversion of body- and sur- face-wave data. For the body-wave data, we used 7190 eve... A new 3D velocity model of the crust and upper mantle in the southeastern (SE) margin of the Tibetan plateau was obtained by joint inversion of body- and sur- face-wave data. For the body-wave data, we used 7190 events recorded by 102 stations in the SE margin of the Tibetan plateau. The surface-wave data consist of Rayleigh wave phase velocity dispersion curves obtained from ambient noise cross-correlation analysis recorded by a dense array in the SE margin of the Tibetan plateau. The joint inversion clearly improves the Vs model because it is constrained by both data types. The results show that at around 10 km depth there are two low-velocity anomalies embedded within three high-velocity bodies along the Longmenshan fault system. These high-velocity bodies correspond well with the Precambrian massifs, and the two located to the northeast of 2013 Ms 7.0 Lushan earthquake are associated with high fault slip areas during the 2008 Wenchuan earthquake. The aftershock gap between 2013 Lushan earthquake and 2008 Wenchuan earthquake is associated with low-velocity anomalies, which also acts as a barrier zone for ruptures of two earthquakes. Generally large earthquakes (M 〉 5) in the region occurring from 2008 to 2015 are located around the high-velocity zones, indicating that they may act as asperities for these large earthquakes. Joint inversion results also clearly show that there exist low-velocity or weak zones in the mid-lower crust, which are not evenly distributed beneath the SE margin of Tibetan plateau. 展开更多
关键词 Joint inversion - Body waves Surface waves Aftershock gap The southeastern margin of Tibetan plateau
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Seismic fluid identification using a nonlinear elastic impedance inversion method based on a fast Markov chain Monte Carlo method 被引量:2
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作者 Guang-Zhi Zhang Xin-Peng Pan +2 位作者 Zhen-Zhen Li Chang-Lu Sun Xing-Yao Yin 《Petroleum Science》 SCIE CAS CSCD 2015年第3期406-416,共11页
Elastic impedance inversion with high efficiency and high stability has become one of the main directions of seismic pre-stack inversion. The nonlinear elastic impedance inversion method based on a fast Markov chain M... Elastic impedance inversion with high efficiency and high stability has become one of the main directions of seismic pre-stack inversion. The nonlinear elastic impedance inversion method based on a fast Markov chain Monte Carlo (MCMC) method is proposed in this paper, combining conventional MCMC method based on global optimization with a preconditioned conjugate gradient (PCG) algorithm based on local optimization, so this method does not depend strongly on the initial model. It converges to the global optimum quickly and efficiently on the condition that effi- ciency and stability of inversion are both taken into consid- eration at the same time. The test data verify the feasibility and robustness of the method, and based on this method, we extract the effective pore-fluid bulk modulus, which is applied to reservoir fluid identification and detection, and consequently, a better result has been achieved. 展开更多
关键词 Elastic impedance nonlinear inversion FastMarkov chain Monte Carlo method - Preconditionedconjugate gradient algorithm ~ Effective pore-fluid bulkmodulus
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Inverse approach to determine piston profile from impact stress waveform on given non-uniform rod 被引量:1
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作者 朱萍玉 刘德顺 +1 位作者 彭佑多 陈安华 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期297-300,共4页
An essential problem in the design of mechanical impact systems is the impact of a piston on a rod. The impact of a semi finite cylindrical piston on a non uniform rod was studied. Based on wave mechanics and characte... An essential problem in the design of mechanical impact systems is the impact of a piston on a rod. The impact of a semi finite cylindrical piston on a non uniform rod was studied. Based on wave mechanics and characteristic line theory, an inverse numerical approach to determine the piston profile was proposed, by means of which the geometry of an impact piston may be determined from the given stress waveform for a given rod profile. Numerical results show that the given stress waveform may be produced by means of the alternatives of design of piston and rod. There is good agreement between the experimental results and numerical results. [ 展开更多
关键词 impact PISTON PROFILE non-UNIFORM ROD inversE numerical approach stress WAVEFORM
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Preparation of Porous Silicone Resin Sheet with Phase Inversion in Parallel with Non Solvent Induced Phase Separation and Application to Hollow Particle Formation
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作者 Takuya Yokoyama Yoshinari Taguchi Masato Tanaka 《Materials Sciences and Applications》 2014年第9期649-659,共11页
We have tried to prepare the porous silicone resin sheet with the phase inversion method in parallel with the non solvent induced phase separation method. In the experiment, ethyl acetate and water were adopted as a g... We have tried to prepare the porous silicone resin sheet with the phase inversion method in parallel with the non solvent induced phase separation method. In the experiment, ethyl acetate and water were adopted as a good solvent and a poor solvent for silicone resin, respectively and ethyl alcohol as an amphiphilic solvent was used to increase the solubility of ethyl acetate in water and decrease the interfacial tension by mass transfer from water to ethyl acetate. The concentration of silicone resin in ethyl acetate and the oil soluble surfactant species were changed. Increasing the concentration of silicone resin could depress coalescence between the water droplets in the (W/O) dispersion and increase the porosity and pore number density of silicone resin sheet. Span 80 among the oil soluble surfactant species made the porosity and pore number density larger. The effect of physical proparties of liquids concerned on the porosity and pore number density was discussed on the basis of dispersing behavior of liquid droplets in the liquid-liquid dispersion. The hollow silicone resin particles could be prepared by applying the preparation method presented here. 展开更多
关键词 POROUS SILICONE RESIN SHEET non Solvent Induced PHASE Separation PHASE inversion HOLLOW SILICONE RESIN Particles
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G-非回归点的拓扑结构和G-平均跟踪性的动力学性质
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作者 冀占江 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第3期308-313,共6页
介绍了G-非回归点和G-平均跟踪性的概念,在群作用下的逆极限空间中研究了G-非回归点的拓扑结构,在度量G-空间中研究了G-平均跟踪性的动力学性质,得到:(1)自映射f有G-非回归点的充要条件是移位映射σ有G-非回归点;(2)如果f^(k)具有G-平... 介绍了G-非回归点和G-平均跟踪性的概念,在群作用下的逆极限空间中研究了G-非回归点的拓扑结构,在度量G-空间中研究了G-平均跟踪性的动力学性质,得到:(1)自映射f有G-非回归点的充要条件是移位映射σ有G-非回归点;(2)如果f^(k)具有G-平均跟踪性,则f具有G-平均跟踪性。这些结果推广了逆极限空间中移位映射非回归点集的结论以及度量空间中迭代映射平均跟踪性的结论。 展开更多
关键词 群作用 逆极限空间 G-非回归点 G-平均跟踪性
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基于Kumaraswamy分布多部件应力-强度模型统计推断
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作者 何飞 蔡静 +1 位作者 何剑 韩荣 《湖北民族大学学报(自然科学版)》 CAS 2024年第3期435-441,共7页
为研究串联系统下多部件应力-强度模型的可靠性问题,基于Kumaraswamy分布,采用极大似然法给出参数及应力-强度模型可靠度的极大似然估计(maximum likelihood estimation,MLE);再利用Jeffreys准则构造无信息先验分布,运用马尔可夫链蒙特... 为研究串联系统下多部件应力-强度模型的可靠性问题,基于Kumaraswamy分布,采用极大似然法给出参数及应力-强度模型可靠度的极大似然估计(maximum likelihood estimation,MLE);再利用Jeffreys准则构造无信息先验分布,运用马尔可夫链蒙特卡洛(Markov chain Monte Carlo,MCMC)方法给出参数及应力-强度模型可靠度的贝叶斯估计;最后,利用逆矩估计方法给出参数及应力-强度模型可靠度的逆矩估计(inverse moment estimation,IME)。数值模拟结果表明,在不同系统可靠度及不同样本量条件下,通过对3种估计方法的数值进行比较发现贝叶斯估计效果最好,IME优于MLE。该研究为探讨串联系统多部件应力-强度模型可靠性提供了一定的理论基础。 展开更多
关键词 Kumaraswamy分布 多部件应力-强度模型 无信息先验 逆矩估计 串联系统 MH算法
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More Peripheral Visualization of Hepatic Arteries by Using Respiratory-Triggered 3D True Steady-State Free-Precession Projection Magnetic Resonance Angiographic Sequences with Time-Spatial Labeling Inversion Pulse
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作者 Daisuke Tsuge Ryohei Kuwatsuru +3 位作者 Tatsuro Inoue Yuki Yamashiro Kazuhiro Suzuki Akihiko Shiraishi 《Open Journal of Radiology》 2014年第4期314-321,共8页
Purpose: To evaluate respiratory-triggered three-dimensional (3D) true steady-state free-precession (SSFP) projection magnetic resonance angiographic sequences with time-spatial labeling inversion pulse (Time-SLIP) fo... Purpose: To evaluate respiratory-triggered three-dimensional (3D) true steady-state free-precession (SSFP) projection magnetic resonance angiographic sequences with time-spatial labeling inversion pulse (Time-SLIP) for visualizing the hepatic arteries and to optimize the image acquisition protocol. Materials and Methods: A 1.5-T clinical magnetic resonance imager was used to perform abdominal magnetic resonance angiography (MRA) in 25 consecutive patients before transcatheter arterial chemoembolization or surgery. We compared two selective space-labeling inversion pulse (tag pulse) patterns (Patterns I and II, oblique and parallel tag pulses, respectively). Two experienced radiologists evaluated the number of hepatic arterial branches visible on the acquired MRA images, and the results were referenced with those on images from intra-arterial digital subtraction angiography. Results: Images were acquired from all patients. The two radiologists clearly visualized branches of the left and right hepatic arteries. More peripheral hepatic arterial branches were identified in MRA images captured by using tag pulse Pattern I than in those acquired by using Pattern II (P P > 0.05). Conclusion: Non-contrast-enhanced Time-SLIP hepatic MRA with true SSFP allowed selective visualization of peripheral hepatic vessels. 展开更多
关键词 Hepatic Artery non-Contrast Magnetic Resonance ANGIOGRAPHY Time-Spatial LABELING inversion PULSE TRUE SSFP ANGIOGRAPHY
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基于Inverse Butterfly/Butterfly网络的置换-逆序与置换-移位选路算法
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作者 马超 戴紫彬 +1 位作者 李伟 南龙梅 《电子学报》 EI CAS CSCD 北大核心 2017年第11期2685-2694,共10页
本文利用Inverse Butterfly/Butterfly多级动态互连网络的自路由和可重排特性,提出了基于该网络的置换-逆序和置换-移位选路算法.它们都能够对所有一次通过该网络的任意置换结果动态地完成逆序和移位操作,且算法复杂度低,硬件实现简洁.... 本文利用Inverse Butterfly/Butterfly多级动态互连网络的自路由和可重排特性,提出了基于该网络的置换-逆序和置换-移位选路算法.它们都能够对所有一次通过该网络的任意置换结果动态地完成逆序和移位操作,且算法复杂度低,硬件实现简洁.进一步,将本文提出的算法对基于该网络设计的置换操作进行了功能扩展,分别构建了置换-逆序、置换-移位以及置换-逆序-移位硬件单元.并将它们在SMIC 65nm工艺下进行了综合,结果表明:当在以往研究成果上扩展逆序操作时,硬件电路面积仅增加约6%且几乎不影响原架构的延迟;当在以往研究成果上扩展移位和逆序-移位操作时,原架构以18%和21%的面积增加值和30%的延迟增加值,实现了功能性2倍的提升. 展开更多
关键词 inversE Butterfly/Butterfly网络 自路由 置换-逆序算法 置换-移位算法
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肥胖儿童non-HDL-C、remnant cholesterol与亚临床动脉粥样硬化的关系 被引量:4
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作者 焦朝艳 刘戈力 +4 位作者 鲍鹏丽 魏莹 杨箐岩 郑荣秀 赵菁 《天津医科大学学报》 2014年第1期25-28,共4页
目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体... 目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体质量儿童30例为III组(对照组)。比较3组儿童血脂指标,对肥胖组各项血脂指标与血浆致动脉粥样硬化指数(AIP)进行相关性分析,肥胖患儿体质指数、血脂指标与颈动脉内径、内膜-中层厚度(c-IMT)、血流参数进行相关性分析。结果:I组、II组的TG、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、non-HDL-C、remnant cholesterol、AIP均较对照组升高,高密度脂蛋白胆固醇(HDL-C)较对照组降低,且I组的remnant cholesterol、AIP均较II组升高。肥胖组儿童AIP与TG、non-HDL-C、remnant cholesterol呈正相关,与HDL-C呈负相关。37例行颈动脉超声检查的肥胖儿童的c-IMT较正常儿童的增厚。结论:non-HDL-C、remnant cholesterol在肥胖儿童亚临床AS中有重要作用,在肥胖儿童血脂异常的治疗中应关注non-HDL-C、remnant cholesterol的变化。 展开更多
关键词 儿童肥胖 亚临床动脉粥样硬化 non—HDL—C REMNANT CHOLESTEROL 血浆致动脉粥样硬化指数 颈动脉内膜-中层厚度
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一部挑战翻译理论传统原则的学术新作——读Challenging the Traditional Axioms: Translation into a Non-Mother Tongue一书
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作者 张奇智 《龙岩学院学报》 2009年第4期74-78,共5页
翻译研究界一般认为译者只能译为其母语,即译者只能进行直接翻译,而译为非母语即逆向翻译则饱受责难。在Challenging the Traditional Axioms:Translation into a Non-Mother Tongue一书中,作者博康以理论分析、语料分析与问卷调查的方... 翻译研究界一般认为译者只能译为其母语,即译者只能进行直接翻译,而译为非母语即逆向翻译则饱受责难。在Challenging the Traditional Axioms:Translation into a Non-Mother Tongue一书中,作者博康以理论分析、语料分析与问卷调查的方式,挑战了"译者只能译为其母语"的传统观念,指出这种观念所赖以生存的"母语"与"本族语者"两个概念的不客观性与非确定性,梳理了翻译理论中与逆向翻译相关的种种观点。此外,博康运用语料分析与问卷调查的方法,指出翻译界种种传统假定的片面性,并论证了"译为非母语"的可行性。 展开更多
关键词 译为母语 直接翻译 译为非母语 逆向翻译 母语 本族语者
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Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced non-small cell lung cancer: a meta-analysis 被引量:13
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作者 Qiang Zhang Yi-Huan Fan +2 位作者 Teng Zhang Xiao-Lan Qin Ji-Fang Song 《TMR Integrative Medicine》 2017年第2期68-78,共11页
Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a syst... Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a systematicsearch in the electronic databases such as Cochrane Library, Pubmed, Embase, Chinese Journal Full-text Database,Chinese Biomedical Literature Database, Chinese Science and Technology Periodical Full-text Database andWanfang Database up to 30 January 2017. Randomized controlled trials (RCT) of Shenqi Fuzheng Injectioncombined with GP chemotherapy in the treatment of advanced NSCLC were searched, and all the RCTs wereconducted on methodological quality assessment. Data extraction and data analysis were according to standards ofCochrane systematic review. Results: Eight trials were included including a total of 701 patients. Meta-analysisresults: Shenqi Fuzheng injection combined with GP chemotherapy could significantly improve the functionalstatus of patients with NSCLC (OR = 3.44, 95% CI [2.26, 5.25], P 〈 0.0001) and clinical treatment efficacy (OR =(OR = 0.31, 95%CI [0.20, 0.47], P 〈 0.0001. The rate of leukopenia (OR = .31, 95%CI [0.20,0.47], P 〈 0.0001),thrombocytopenia (OR = 0.58, 95%CI [0.37, 0.91], P = 0.020), hemoglobin decline ((OR = 0.31, 95%CI [0.16,0.59], P = 0.0004) and incidence of gastrointestinal reactions (OR = 0.58,P 〈 0.05) could be reduced. Conclusion:Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced NSCLC obtainedsignificantly clinical efficacy. The quality of the literature incorporated is low, the conclusion requires high-qualityresearch to further prove. 展开更多
关键词 Shenqi Fuzheng GP chemotherapy Advanced non - small cell lung cancer Meta analysis
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基于non-local先验的贝叶斯变量选择方法及其在高维数据分析中的应用
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作者 马金沙 董晓强 +4 位作者 高倩 陶然 许树红 李艳艳 王彤 《中国卫生统计》 CSCD 北大核心 2020年第3期372-377,383,共7页
目的对高维数据进行变量筛选并构建预测模型是组学数据分析的研究热点之一。本研究旨在为结局为二分类变量的高维组学数据筛选自变量并构建预测结局的稀疏统计模型。方法本研究通过模拟研究和实例分析阐释基于non-local先验的贝叶斯变... 目的对高维数据进行变量筛选并构建预测模型是组学数据分析的研究热点之一。本研究旨在为结局为二分类变量的高维组学数据筛选自变量并构建预测结局的稀疏统计模型。方法本研究通过模拟研究和实例分析阐释基于non-local先验的贝叶斯变量选择方法--乘积逆矩先验(product inverse moment,piMOM)相较于惩罚类方法ISIS-光滑平切绝对偏差(iterative sure independence screening-smoothly clipped absolute deviation,ISIS-SCAD)和ISIS-最小最大凹惩罚(iterative sure independence screening-minimax concave penalty,ISIS-MCP)在高维数据中变量筛选及其预测效果的性能优劣。结果模拟研究发现:在高维的情况下,经piMOM、ISIS-SCAD和ISIS-MCP方法筛选所得变量的平均真阳性数和受试者工作特征曲线下面积(AUC,area under curve)基本相等,ISIS-SCAD、ISIS-MCP的平均假阳性数、回归系数均方误差以及预测均方误差明显高于基于non-local先验的贝叶斯变量方法所获得的对应值。piMOM方法分析弥漫大B细胞淋巴瘤实例数据共识别5个有意义的基因,AUC为0.996;ISIS-SCAD识别7个基因,AUC为0.975;ISIS-MCP识别7个基因,AUC为0.968。结论在模型选择相合性和预测准确性方面,piMOM方法与ISIS-SCAD和ISIS-MCP相比,具有优势,在一定意义上可有效控制假阳性率。 展开更多
关键词 高维数据 贝叶斯变量选择方法 non-local先验 乘积逆矩先验 弥漫性大B细胞淋巴瘤
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A New Inversion Method of Sedimentary Strata For Deriving Double Parameters and Its Applications 被引量:1
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作者 GUO Hua, LIU Cai, LI Yue and YANG Baojun(College of Geo-exploration Science and Technology, Jilin University, Changchun 130026, P. R. China) 《Global Geology》 2002年第1期79-88,共10页
The inverse problem of wave equation is the importance of study not only in seismic prospecting but also in applied mathematics. With the development of the research, the inverse methods of 1 - D wave equations have b... The inverse problem of wave equation is the importance of study not only in seismic prospecting but also in applied mathematics. With the development of the research, the inverse methods of 1 - D wave equations have been trending towards the multiple parameters inversion . We have obtained an inverse method with double -parameter, in which medium density and wave velocity can be derived simultaneously. In this paper, to increase the inverse accuracy, the method is improved as follows. Firstly, the formula in which the Green Function is omitted are derived and used. Secondly, the regularizing method is reasonable used by choosing the stable function. With the new method, we may derive elastic parameter and medium density or medium density and wave velocity. Thus, lithology parameters for seismic prospecting may be obtained.After comparing the derived values from the new method with that from previous method, we obtain the new method through which substantially improve the derived accuracy . The new method has been applied to real depths inversion for sedimentary strata and volcanic rock strata in Chaoyanggou Terrace of Songliao Basin in eastern China. According to the inverse results,the gas - bearing beds are determlned. 展开更多
关键词 SEDIMENTARY strata DOUBLE - Parameter inversion Green function Regularization method FREDHOLM integral equation of the first kind VOLCANIC rock STRATA
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Photon-added and photon-subtracted displaced Fock states and their non-classical properties 被引量:1
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作者 司坤 张淼 贾焕玉 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4887-4892,共6页
A new kind of quantum optical state, photon-added and -subtracted displaced Fock states, is introduced by applying the inverse of bosonic creation and annihilation operators to displaced Fock states. The quantum stati... A new kind of quantum optical state, photon-added and -subtracted displaced Fock states, is introduced by applying the inverse of bosonic creation and annihilation operators to displaced Fock states. The quantum statistical properties of these states are investigated by numerical methods. Numerical results indicate that these states reveal some interesting non-classical properties, such as anti-bunching effects, sub-Poisson distributions and negativities of their Wigner functions. 展开更多
关键词 Boson inverse operators photon-added and -subtracted states non-classical property
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Electron transport in electrically biased inverse parabolic double-barrier structure 被引量:1
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作者 M Bati S Sakiroglu I Sokmen 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期326-332,共7页
A theoretical study of resonant tunneling is carried out for an inverse parabolic double-barrier structure subjected to an external electric field. Tunneling transmission coefficient and density of states are analyzed... A theoretical study of resonant tunneling is carried out for an inverse parabolic double-barrier structure subjected to an external electric field. Tunneling transmission coefficient and density of states are analyzed by using the non-equilibrium Green's function approach based on the finite difference method. It is found that the resonant peak of the transmission coefficient, being unity for a symmetrical case, reduces under the applied electric field and depends strongly on the variation of the structure parameters. 展开更多
关键词 inverse parabolic double-barrier structure resonant tunneling non-equilibrium Green's function electric field
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Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field
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作者 Hong-tao Zheng Zhi-yong Tan +2 位作者 Hai-ou Sun Chun-liang Zhou Zhi-ming Li 《Journal of Marine Science and Application》 2002年第1期26-34,共9页
Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved... Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec- 展开更多
关键词 plasma GENERATOR CHEMISTRY non - EQUILIBRIUM IGNITION technique numerical calculation
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