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Adjuvant chemotherapy for isolated resectable colorectal lung metastasis: A retrospective study using inverse probability treatment weighting propensity analysis
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作者 Zhao Gao Shi-Kai Wu +3 位作者 Shi-Jie Zhang Xin Wang Ying-Chao Wu Xuan Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3171-3184,共14页
BACKGROUND The benefit of adjuvant chemotherapy(ACT)for patients with no evidence of disease after pulmonary metastasis resection(PM)from colorectal cancer(CRC)remains controversial.AIM To assess the efficacy of ACT i... BACKGROUND The benefit of adjuvant chemotherapy(ACT)for patients with no evidence of disease after pulmonary metastasis resection(PM)from colorectal cancer(CRC)remains controversial.AIM To assess the efficacy of ACT in patients after PM resection for CRC.METHODS This study included 96 patients who underwent pulmonary metastasectomy for CRC at a single institution between April 2008 and July 2023.The primary end-point was overall survival(OS);secondary endpoints included cancer-specific survival(CSS)and disease-free survival(DFS).An inverse probability of treat-ment-weighting(IPTW)analysis was conducted to address indication bias.Sur-vival outcomes compared using Kaplan-Meier curves,log-rank test,Cox regre-ssion and confirmed by propensity score-matching(PSM).RESULTS With a median follow-up of 27.5 months(range,18.3-50.4 months),the 5-year OS,CSS and DFS were 72.0%,74.4%and 51.3%,respectively.ACT had no significant effect on OS after PM resection from CRC[original cohort:P=0.08;IPTW:P=0.15].No differences were observed for CSS(P=0.12)and DFS(P=0.68)between the ACT and non-ACT groups.Multivariate analysis showed no association of ACT with better survival,while sublobar resection(HR=0.45;95%CI:0.20-1.00,P=0.049)and longer disease-free interval(HR=0.45;95%CI:0.20-0.98,P=0.044)were associated with improved survival.CONCLUSION ACT does not improve survival after PM resection for CRC.Further well-designed randomized controlled trials are needed to determine the optimal ACT regimen and duration. 展开更多
关键词 Colorectal cancer Resection of pulmonary metastasis Adjuvant chemotherapy inverse probability treatment weighting Prognosis
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Fast inversion of array laterolog measurements in an axisymmetric medium
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作者 Hu Song Chen Long Wang Jin 《Applied Geophysics》 SCIE CSCD 2019年第4期539-548,562,共11页
The array laterolog is an important tool for complex formation logging evaluation due to its high resolution and large detection depth.However,its logging responses are seriously affected by leakage events due to the ... The array laterolog is an important tool for complex formation logging evaluation due to its high resolution and large detection depth.However,its logging responses are seriously affected by leakage events due to the surrounding rock and by mud invasion.These factors must be considered when inverting array lateral logging data,so that the inversion results reflect the true formation conditions as much as possible.The difficulties encountered in the inversion of array lateral logging data are:too many inversion parameters cause the calculation of the Jacobian matrix to be difficult and the time required to select the initial inversion values due to the slow forward-modeling speed.In this paper,we develop a fast processing method for array laterolog data.First,it is important to clearly define the main controlling factors for the array laterolog response,such as thickness,the surrounding rock,and invasion.Second,based on a depth-window technique,processing the array laterolog data for the entire well is transformed into multiple 2 D inversions of the layers using a series of continuous depth windows.For each formation in a depth window,combined with the1 D equivalent fast-forward algorithm,rapid extraction of the radial resistivity profile of the formation is achieved.Finally,the 1 D inversion result is used as the initial state to further eliminate the influence of surrounding rocks and layer thicknesses on the apparent resistivity response.Numerical simulation results show that the factors affecting the response of the array laterolog are the invasion properties,the layer thicknesses,and the surrounding rocks;the windowing technique greatly reduces the number of inversion parameters needed and improves the inversion speed.A real application of the method shows that 2 D inversion can rapidly reconstruct the actual resistivity distribution and improve the accuracy of reservoir saturation calculations. 展开更多
关键词 array laterolog 2D inversion invasion profile windowing treatment 1D inversion
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Conservative management of a recurrent puerperal uterine inversion with bakri<sup>®</sup>balloon tamponade
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作者 Jesús Joaquín Hijona Elósegui Francisco Javier Frutos Arenas +3 位作者 Antonio Carballo García Juan Antonio López López Gabriel Castilla Peinado Peinado Juan Manuel Torres Martí 《Open Journal of Obstetrics and Gynecology》 2011年第4期197-201,共5页
Puerperal Uterine Inversion (PUI) is a rare but potentially life-threatening delivery complication in which the uterine fundus collapses within the endometrial cavity. This “glove-finger” introflexion of uterine wal... Puerperal Uterine Inversion (PUI) is a rare but potentially life-threatening delivery complication in which the uterine fundus collapses within the endometrial cavity. This “glove-finger” introflexion of uterine walls generally occurs as an immediate postpartum complication and is responsible of different degrees of vaginal bleeding, shock and hypogastric pain that can cause serious maternal complications, including death. There are few reports of recurrent postpartum uterine inversion like the one we present here, and its causes remain unclear. Early diagnosis of this complication is crucial as it is the only one measure that can allow a successful and conservative treatment: an inverse relationship between the time that uterus keeps inverted and the probability of repositioning has been firmly established. This case report describes the exceptional and innovative use of the SOS Bakri? balloon (Cook Medical Incorporated) in the management of a recurrent puerperal uterine inversion. To our knowledge it is one of the first reports in the world of this procedure, perhaps the second one after Soleymani’s et al description;and the first one in a third degree recurrent puerperal uterine inversion. 展开更多
关键词 BALLOON TAMPONADE INTRAUTERINE Management POSTPARTUM HAEMORRHAGE Uterine inversion Review treatment
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Non-Relativistic Treatment of a Generalized Inverse Quadratic Yukawa Potential
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作者 Oluwatimilehin Oluwadare Kayode Oyewumi 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期1-5,共5页
A bound state solution is a quantum state solution of a particle subjected to a potential such that the particle's energy is less than the potential at both negative and positive infinity. The particle's energy may ... A bound state solution is a quantum state solution of a particle subjected to a potential such that the particle's energy is less than the potential at both negative and positive infinity. The particle's energy may also be negative as the potential approaches zero at infinity. It is characterized by the discretized eigenvalues and eigenfunctions, which contain all the necessary information regarding the quantum systems under consideration. The bound state problems need to be extended using a more precise method and approximation scheme. This study focuses on the non-relativistic bound state solutions to the generalized inverse quadratic Yukawa potential. The expression for the non-relativistic energy eigenvalues and radial eigenfunctions are derived using proper quantization rule and formula method, respectively. The results reveal that both the ground and first excited energy eigenvalues depend largely on the angular momentum numbers, screening parameters, reduced mass, and the potential depth. The energy eigenvalues, angular momentum numbers, screening parameters, reduced mass, and the potential depth or potential coupling strength determine the nature of bound state of quantum particles. The explored model is also suitable for explaining both the bound and continuum states of quantum systems. 展开更多
关键词 In Non-Relativistic treatment of a Generalized inverse Quadratic Yukawa Potential
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Photovoltaic Properties of CdSe Quantum Dot Sensitized Inverse Opal TiO<sub>2</sub>Solar Cells: The Effect of TiCl<sub>4</sub>Post Treatment
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作者 Motoki Hironaka Taro Toyoda +3 位作者 Kanae Hori Yuhei Ogomi Shuzi Hayase Qing Sheng 《Journal of Modern Physics》 2017年第4期522-530,共9页
Recently, semiconductor quantum dot (QD) sensitized solar cells (QDSSCs) are expected to achieve higher conversion efficiency because of the large light absorption coefficient and multiple exciton generation in QDs. T... Recently, semiconductor quantum dot (QD) sensitized solar cells (QDSSCs) are expected to achieve higher conversion efficiency because of the large light absorption coefficient and multiple exciton generation in QDs. The morphology of TiO2 electrode is one of the most important factors in QDSSCs. Inverse opal (IO) TiO2 electrode, which has periodic mesoporous structure, is useful for QDSSCs because of better penetration of electrolyte than conventional nanoparticulate TiO2 electrode. In addition, the ordered three dimensional structure of IO-TiO2 would be better for electron transport. We have found that open circuit voltage Voc of QDSSCs with IO-TiO2 electrodes was much higher (0.2 V) than that with nanoparticulate TiO2 electrodes. But short circuit current density Jsc was lower in the case of IO-TiO2 electrodes because of the smaller surface area of IO-TiO2. In this study, for increasing surface area of IO-TiO2, we applied TiCl4 post treatment on IO-TiO2 and investigated the effect of the post treatment on photovoltaic properties of CdSe QD sensitized IO-TiO2 solar cells. It was found that Jsc could be enhanced due to TiCl4 post treatment, but decreased again for more than one cycle treatment, which indicates excess post treatment may lead to worse penetration of electrolyte. Our results indicate that the appropriate post treatment can improve the energy conversion efficiency of the QDSSCs. 展开更多
关键词 Quantum DOT Sensitized Solar Cells inverse OPAL Structure TICL4 Post treatment Morphology of the TiO2 Electrode
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Optimal Aerations in the Inverse Fluidized Bed Biofilm Reactor When Used in Treatment of Industrial Wastewaters of Various Strength
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作者 Wlodzimierz Sokól 《Advances in Chemical Engineering and Science》 2012年第3期384-391,共8页
The aim of this work was the determination of the optimal aerations, and more specifically the corresponding optimal air velocities uopt, at which the largest COD removals were achieved in treatment of industrial wast... The aim of this work was the determination of the optimal aerations, and more specifically the corresponding optimal air velocities uopt, at which the largest COD removals were achieved in treatment of industrial wastewaters of various strength conducted in the inverse fluidized bed biofilm reactor. The largest COD removals were achieved at the following air velocities uopt and retention times ts, and (Vb/VR) = 0.55: i) for CODo = 72,780 mg/l at uopt = 0.052 m/s and ts = 80 h;ii) for CODo = 62,070 mg/l at uopt = 0.042 m/s and ts = 65 h;iii) for CODo = 49,130 mg/l at uopt = 0.033 m/s and ts= 55 h;iv) for CODo = 41,170 mg/l at uopt = 0.028 m/s and ts = 45 h;v) for CODo = 35,460 mg/l at uopt = 0.025 m/s and ts = 27.5 h;and vi) for CODo = 26,470 mg/l at uopt= 0.014 m/s and ts = 22.5 h. In the treatment operation conducted in a reactor optimally controlled at the above values of uopt, ts and (Vb/VR), the following decreases in COD were obtained: i) from 72,780 to 5410 mg/l;ii) from 62,070 to 3730 mg/l;iii) from 49,130 to 2820 mg/l;iv) from 41,170 to 1820 mg/l;v) from 35,460 to 1600 mg/l;and vi) from 26,470 to 1180 mg/l, that is, approximately a 93%, 94%, 95%, 96%, 95% and 96% COD reduction was attained, respectively. 展开更多
关键词 Optimal Aeration Aerobic Wastewater treatment Biological Wastewater treatment inverse Biofilm Reactor Fluidized Bed Bioreactor Low-Density Biomass Support
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Effectiveness of antibiotic prophylaxis for acute esophageal variceal bleeding in patients with band ligation: A large observational study 被引量:1
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作者 Chikamasa Ichita Sayuri Shimizu +4 位作者 Tadahiro Goto Uojima Haruki Naoya Itoh Masao Iwagami Akiko Sasaki 《World Journal of Gastroenterology》 SCIE CAS 2024年第3期238-251,共14页
BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and... BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and Western guidelines recom-mend antibiotic prophylaxis following hemostasis.However,given the impro-vements in prognosis for variceal bleeding due to advancements in the management of bleeding and treatments of liver cirrhosis and the global concerns regarding the emergence of multidrug-resistant bacteria,there is a need to reassess the use of routine antibiotic prophylaxis after hemostasis.AIM To evaluate the effectiveness of antibiotic prophylaxis in patients treated for EVL.METHODS We conducted a 13-year observational study using the Tokushukai medical database across 46 hospitals.Patients were divided into the prophylaxis group(received antibiotics on admission or the next day)and the non-prophylaxis group(did not receive antibiotics within one day of admission).The primary outcome was composed of 6-wk mortality,4-wk rebleeding,and 4-wk spontaneous bacterial peritonitis(SBP).The secondary outcomes were each individual result and in-hospital mortality.A logistic regression with inverse probability of treatment weighting was used.A subgroup analysis was conducted based on the Child-Pugh classification to determine its influence on the primary outcome measures,while sensitivity analyses for antibiotic type and duration were also performed.RESULTS Among 980 patients,790 were included(prophylaxis:232,non-prophylaxis:558).Most patients were males under the age of 65 years with a median Child-Pugh score of 8.The composite primary outcomes occurred in 11.2%of patients in the prophylaxis group and 9.5%in the non-prophylaxis group.No significant differences in outcomes were observed between the groups(adjusted odds ratio,1.11;95%confidence interval,0.61-1.99;P=0.74).Individual outcomes such as 6-wk mortality,4-wk rebleeding,4-wk onset of SBP,and in-hospital mortality were not significantly different between the groups.The primary outcome did not differ between the Child-Pugh subgroups.Similar results were observed in the sensitivity analyses.CONCLUSION No significant benefit to antibiotic prophylaxis for esophageal variceal bleeding treated with EVL was detected in this study.Global reassessment of routine antibiotic prophylaxis is imperative. 展开更多
关键词 Esophageal varices Endoscopic hemostasis Antibiotic prophylaxis Liver cirrhosis inverse probability of treatment weighting
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基于倾向性评分逆概率加权法的视网膜母细胞瘤疗效评价及其预后影响因素分析
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作者 石丽娟 李丽 +2 位作者 石福艳 周希彬 吴志鸿 《解放军医学杂志》 CAS CSCD 北大核心 2024年第3期302-307,共6页
目的评估手术、化疗及手术联合化疗3种治疗方式对视网膜母细胞瘤(RB)的疗效,分析RB患者的预后影响因素。方法选取2000年1月1日-2019年12月31日美国监测、流行病学和最终结果(SEER)数据库登记的RB患者1188例临床资料进行回顾性分析。采... 目的评估手术、化疗及手术联合化疗3种治疗方式对视网膜母细胞瘤(RB)的疗效,分析RB患者的预后影响因素。方法选取2000年1月1日-2019年12月31日美国监测、流行病学和最终结果(SEER)数据库登记的RB患者1188例临床资料进行回顾性分析。采用倾向性评分逆概率加权法(IPTW)对接受手术、化疗或手术联合化疗治疗的3组患者基线特征进行平衡。采用Log-rank检验比较3组患者的生存概率,采用Cox回归模型分析RB患者预后影响因素。结果共纳入RB1188例,其中手术组426例,化疗组200例,手术联合化疗组562例。经IPTW加权后,患者的年龄、性别、种族等基线资料均达到平衡(P>0.05)。Log-rank检验结果显示,加权前后3组生存曲线比较差异均有统计学意义(P<0.05);加权后,手术组患者生存情况明显优于化疗组和手术联合化疗组(P<0.05),化疗组与手术联合化疗组比较差异无统计学意义(P>0.05)。加权后患者1年、3年和5年的生存概率为:手术组99.7%、98.9%和98.6%;化疗组97.4%、95.8%和95.8%;手术联合化疗组97.9%、95.8%和95.0%。Cox回归分析结果显示,与手术组比较,化疗组患者特异性死亡风险比为1.367(95%CI 1.100~1.700),手术联合化疗组特异性死亡风险比为1.132(95%CI0.963~1.330);与RB病灶为1个的患者比较,RB病灶数≥2个的患者特异性死亡风险比为0.399(95%CI0.268~0.594)。结论RB患者接受治疗后生存概率较高;在控制年龄、性别等因素的影响后,3种治疗方式中手术的疗效更好;多灶性可能是RB患者预后的独立影响因素。 展开更多
关键词 视网膜母细胞瘤 逆概率加权 疗效 生存分析
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病毒感染与睡眠障碍之间的关联性——基于NHANES数据库的横断面研究
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作者 莫初叶 康旖雯 +7 位作者 袁宗祥 张君涵 王凤仪 覃芳 黄诗卉 蒋俊俊 梁浩 叶力 《广西医学》 CAS 2024年第1期122-128,共7页
目的基于国家健康和营养检查调查(NHANES)数据库探讨多种病毒感染与睡眠障碍之间的关联性。方法选取NHANES数据库2009—2010年的横断面调查数据,根据睡眠障碍发生情况将研究对象分为睡眠障碍组与非睡眠障碍组。采用逆概率处理加权法(IP... 目的基于国家健康和营养检查调查(NHANES)数据库探讨多种病毒感染与睡眠障碍之间的关联性。方法选取NHANES数据库2009—2010年的横断面调查数据,根据睡眠障碍发生情况将研究对象分为睡眠障碍组与非睡眠障碍组。采用逆概率处理加权法(IPTW)平衡两组研究对象的基线特征。采用χ^(2)检验及标准均数差(SMD)评估IPTW分析前后两组基线特征的均衡性;应用非条件Logistic回归(IPTW分析前)和加权Logistic回归(IPTW分析后)分析7种病毒感染与睡眠障碍之间的关联性。针对HAV感染与睡眠障碍之间的关联性进行亚组分析。结果共纳入2385名研究对象,其中146名纳入睡眠障碍组,2239名纳入非睡眠障碍组。IPTW分析前,两组的年龄、人群、家庭收入贫困比率(PIR)、吸烟的SMD>0.1,基本特征不均衡;IPTW分析后,两组的基线特征差异无统计学意义(SMD<0.1,P>0.05),基本特征均衡。非条件Logistic回归结果显示,HAV感染、单纯疱疹病毒2型(HSV-2)感染与睡眠障碍存在相关性(P<0.05);加权Logistic回归结果显示,HSV-2感染者发生睡眠障碍的风险约为未感染者的1.93倍(P<0.05),而HAV感染与睡眠障碍无相关性(P>0.05)。亚组分析显示,HAV感染与睡眠障碍的关联性受年龄与教育水平等混杂因素显著影响(P交互作用<0.05)。结论经IPTW平衡基线特征后,HSV-2感染与睡眠障碍存在显著性关联。应对HSV-2感染者进行睡眠障碍情况筛查和干预,以提高该人群睡眠质量。 展开更多
关键词 睡眠障碍 病毒感染 逆概率处理加权法 国家健康和营养检查调查数据库
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基于逆概率加权法分析急诊救治通道对上消化道出血患者治疗效果的影响
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作者 勾伟锋 周晓倩 +1 位作者 邓谍 江经斌 《中国中西医结合急救杂志》 CAS CSCD 2024年第2期203-207,共5页
目的通过倾向性评分逆概率加权法(IPTW)探讨上消化道出血急诊救治通道对急性上消化道出血(AUGIB)患者的临床治疗效果。方法采用回顾性研究方法。纳入2018年1月至2021年12月贵阳市第一人民医院收治的299例AUGIB患者的临床信息,选择急诊... 目的通过倾向性评分逆概率加权法(IPTW)探讨上消化道出血急诊救治通道对急性上消化道出血(AUGIB)患者的临床治疗效果。方法采用回顾性研究方法。纳入2018年1月至2021年12月贵阳市第一人民医院收治的299例AUGIB患者的临床信息,选择急诊救治通道建立前(2018年1月至2019年12月)收治的AUGIB患者为常规组(152例),以急诊救治通道建立后(2020年1月至2021年12月)收治的AUGIB患者为通道组(147例)。采用IPTW对多个混杂变量性别、年龄、既往基础疾病、非甾体抗炎药(NSAID)服用史、个人史、格拉斯哥Blatchford评分(GBS)、不同出血病因等进行平衡,经IPTW处理后实现混杂变量在组间的一致分布。比较常规组与通道组临床治疗效果的差异,包括止血时间、出血复发率、输血量、住院时间、住院费用、重症监护病房(ICU)转入率、病死率等。结果经IPTW后,混杂变量在组间均衡效果好。通道组止血时间〔h:7.90(5.36,11.42)比9.92(6.25,18.15)〕、出血复发率〔23.1%(34/147)比40.1%(61/152)〕、住院时间〔d:8.00(7.00,10.34)比9.00(7.00,13.00)〕、ICU转入率〔8.8%(13/147)比17.7%(27/152)〕、病死率〔0.7%(1/147)比4.5%(7/152)〕均明显低于常规组(均P<0.05);通道组和常规组输血量、住院费用比较差异均无统计学意义〔输血量(U):2(0,4)比2(0,4),住院费用(万元):1.35(1.03,2.00)比1.16(0.71,2.29),均P>0.05〕。结论该急诊救治通道能降低AUGIB患者的出血复发率、ICU转入率及病死率,缩短止血时间和住院时间,具有很好的治疗效果。 展开更多
关键词 急诊救治通道 格拉斯哥Blatchford评分 逆概率加权法 治疗效果
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铝合金在接触固溶处理工艺中的界面传热系数
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作者 苏雪荣 宋振坤 张志强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期453-464,共12页
采用有限元模拟和反演优化(IO)方法测定7075铝合金在不同压力、表面粗糙度和温度下接触固溶处理过程中的界面传热系数(IHTC)值,并分析这些因素对IHTC的影响。结果表明:随着压力的增加,IHTC值先增加,然后保持稳定;IHTC值随表面粗糙度的... 采用有限元模拟和反演优化(IO)方法测定7075铝合金在不同压力、表面粗糙度和温度下接触固溶处理过程中的界面传热系数(IHTC)值,并分析这些因素对IHTC的影响。结果表明:随着压力的增加,IHTC值先增加,然后保持稳定;IHTC值随表面粗糙度的增大而减小;随着板温的升高,瞬时IHTC值先增大后减小。基于压力、表面粗糙度和温度的综合影响规律,建立多因素影响的IHTC理论模型。使用此模型能较好地预测不同条件下合金的瞬时IHTC值。 展开更多
关键词 铝合金 接触固溶处理 界面传热系数 有限元分析 反演优化
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旋覆代赭汤现代临床应用概述
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作者 翟冬妍 吕冠华 范颖 《中医药临床杂志》 2024年第2期382-386,共5页
旋覆代赭汤出自《伤寒论》,是治疗胃虚气逆痰阻之“心下痞”的代表方。现代临床扩大了旋覆代赭汤的应用范围,旋覆代赭汤不仅应用于消化系统,在其他系统中也取得了良好的疗效,充分体现了中医“异病同治”的特点。文章对近年来旋覆代赭汤... 旋覆代赭汤出自《伤寒论》,是治疗胃虚气逆痰阻之“心下痞”的代表方。现代临床扩大了旋覆代赭汤的应用范围,旋覆代赭汤不仅应用于消化系统,在其他系统中也取得了良好的疗效,充分体现了中医“异病同治”的特点。文章对近年来旋覆代赭汤的临床应用进行了综述,旨在拓宽旋覆代赭汤临床思路。 展开更多
关键词 旋覆代赭汤 胃虚气逆 临床应用 概述 异病同治
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基于双重稳健估计方法的非小细胞肺癌治疗过程对院内死亡的因果效应研究
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作者 李健 李倩妮 +2 位作者 徐灵燕 姚雪佩 刘美娜 《实用肿瘤学杂志》 CAS 2024年第4期235-240,共6页
目的基于双重稳健估计(Doubly robust,DR)方法估计非小细胞肺癌治疗过程对院内死亡的因果效应大小,为降低非小细胞肺癌院内死亡率提供参考依据。方法依据非小细胞肺癌治疗质量评价体系,计算治疗过程指标的使用率,以治疗过程质量均值得... 目的基于双重稳健估计(Doubly robust,DR)方法估计非小细胞肺癌治疗过程对院内死亡的因果效应大小,为降低非小细胞肺癌院内死亡率提供参考依据。方法依据非小细胞肺癌治疗质量评价体系,计算治疗过程指标的使用率,以治疗过程质量均值得分为界限将患者划分为高质量组与低质量组。以院内死亡为结局指标,采用倾向性评分逆概率加权(Inverse probability of treatment weighting,IPTW)法校正的Kaplan-Meier法及Cox回归,分析治疗过程质量对非小细胞肺癌院内死亡的影响;结合DR估计治疗过程对院内死亡的因果效应大小。结果治疗过程指标使用率的中位数为66.88%,患者治疗过程质量得分为0.270±0.124,其中高质量组为0.358±0.069,低质量组为0.158±0.081。经过IPTW法加权后,患者基线特征标准化平均差(Standardized mean difference,SMD)减小;IPTW前后两组患者生存曲线间差异具有统计学意义(P<0.05),高质量组患者的预后优于低质量组患者(IPTW前:HR=0.367,95%CI:0.275~0.491;IPTW后:HR=0.228,95%CI:0.167~0.312)。与低质量组相比,高质量组患者治疗过程对院内死亡的平均因果效应大小为-0.026。结论DR可弥补logistic或IPTW的不足,规避模型出错的风险,可以获得治疗过程质量对院内死亡的因果效应。医疗实践中应提高治疗过程指标的使用率,从而改善患者预后;因果效应研究提示,除治疗过程外,影响院内死亡的其他因素也是不可忽略的。 展开更多
关键词 非小细胞肺癌 倾向性评分 逆概率加权 双重稳健估计 治疗质量
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母亲MTR基因多态性及其与围孕期叶酸补充的交互作用与子代室间隔缺损的关联研究
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作者 阮霄睿 孙梦婷 +5 位作者 魏剑晖 罗曼君 刘涵君 唐嘉鹏 李柳萱 秦家碧 《中国当代儿科杂志》 CAS CSCD 北大核心 2024年第9期899-906,共8页
目的探讨母亲MTR基因多态性及其与围孕期叶酸补充的交互作用与子代室间隔缺损(ventricular septal defect,VSD)的关联。方法采用病例对照研究,招募426例1岁以内VSD患儿母亲和740例同年龄段健康婴儿母亲。通过问卷调查收集母亲相关暴露信... 目的探讨母亲MTR基因多态性及其与围孕期叶酸补充的交互作用与子代室间隔缺损(ventricular septal defect,VSD)的关联。方法采用病例对照研究,招募426例1岁以内VSD患儿母亲和740例同年龄段健康婴儿母亲。通过问卷调查收集母亲相关暴露信息,并采集其血液标本进行基因多态性检测。采用多因素logistic回归和逆概率加权法处理后logistic回归分析位点与VSD的关联。使用叉生分析和logistic回归分析探讨位点与叶酸补充间的相加和相乘交互作用。结果母亲MTR基因rs6668344位点CT和TT型增加了子代对VSD的易感性(P<0.05)。rs3768139位点GC和CC型、rs1050993位点AG和GG型、rs4659743位点AT和TT型、rs3768142位点GG型、rs3820571位点GT和TT型与VSD发生风险降低有关(P<0.05)。rs6668344位点变异与叶酸补充对VSD存在拮抗相乘交互作用(P<0.05)。结论母亲MTR基因多态性与子代VSD发生显著相关。rs6668344位点变异者围孕期叶酸补充可降低其子代VSD易感性,提示遗传高风险人群更应补充叶酸以预防子代VSD的发生。 展开更多
关键词 室间隔缺损 MTR基因 单核苷酸多态性 逆概率处理加权 交互作用 子代
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Microstructure and Properties of PET Fabric Grafted by Polyacrylic Acid with Inverse Microemulsion Polymerization 被引量:1
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作者 石小丽 陶然 +1 位作者 朱新生 潘志娟 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期624-628,共5页
Annual production output of poly(ethylene terephthalate)(PET) fiber has been over 15 million tons in China due to its good mechanical properties and processability,but the shortage of hydrophilic group of PET has impo... Annual production output of poly(ethylene terephthalate)(PET) fiber has been over 15 million tons in China due to its good mechanical properties and processability,but the shortage of hydrophilic group of PET has imposed many limitations to further extend its application.The PET fabrics were grafted with polyacrylic acid in inverse microemulsion after low pressure plasma treatment,and the microstructure and properties of the grafted fabrics were investigated with infrared spectroscopy,scanning electron microscope(SEM),hydrophilic and mechanical tests.The grafting yield was increased with the grafting time.The grafting polymer was in the granular form with its particle size ranging from a few micrometers to a dozen of micrometers,normally smaller than the fiber diameter.The moisture regain and water uptake increased while the air permeability of the grafted fabrics decreased with the increase of grafting yield.The bending rigidity and tensile properties show slightly complicated behaviors with grafting yield.The inverse emulsion grafting technique can be used to control the grafting polymer architecture. 展开更多
关键词 poly(ethylene terephthalate)(PET) plasma treatment inverse emulsion GRAFTING air permeability mechanical properties HYDROPHILICITY
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Evaluation of the Inverse Fluidized Bed Biological Reactor for Treating High-Strength Industrial Wastewaters 被引量:5
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作者 Wlodzimierz Sokól Belay Woldeyes 《Advances in Chemical Engineering and Science》 2011年第4期239-244,共6页
The aim of this work was to investigate the aerobic degradation of high-strength industrial (refinery) wastewaters in the inverse fluidized bed biological reactor, in which polypropylene particles of density 910 kg/m3... The aim of this work was to investigate the aerobic degradation of high-strength industrial (refinery) wastewaters in the inverse fluidized bed biological reactor, in which polypropylene particles of density 910 kg/m3 were fluidized by an upward flow of gas through a bed. Measurements of chemical oxygen demand (COD) versus residence time t were performed for various ratios of settled bed volume to reactor volume (Vb/VR) and air velocities u. The largest COD reduction, namely, from 54,840 to 2,190 mg/l, i.e. a 96% COD decrease, was achieved when the reactor was operated at the ratio (Vb/VR) = 0.55, air velocity u = 0.046 m/s and t = 65 h. Thus, these values of (Vb/VR), u and t can be considered as the optimal operating parameters for a reactor when used in treatment of high-strength refinery wastewaters. In the treatment operation conducted in a reactor optimally controlled at (Vb/VR) = 0.55, u = 0.046 m/s and t = 65 h, the conversions obtained for all phenolic constituents of the wastewater were larger than 95%. The conversions of about 90% were attained for other hydrocarbons. 展开更多
关键词 Biological Wastewater treatment Aerobic Wastewater treatment High-Strength Industrial Wastewaters inverse Biological Reactor Fluidized Bed Bioreactor Low-Density Biomass Support
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Verification of Inverse Quench-Hardening Phenomena in Bearing Steel Specimens by Experiment and Computer Simulation
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作者 Kyozo Arimoto Chuanrong Jin +2 位作者 Shigeyuki Tamura Kiyoshi Funatani Mamoru Tajima 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期465-470,共6页
The appearance of lower hardness at the surface than at the core after through-hardening of steels is known as "inverse quench-hardening." Pioneering work was performed in the 1970s by establishing a simple ... The appearance of lower hardness at the surface than at the core after through-hardening of steels is known as "inverse quench-hardening." Pioneering work was performed in the 1970s by establishing a simple test procedure where cylindrical specimens were cooled by air and brine sequentially to produce the effect. This phenomenon was described in relation to the polymer quenching and its effect to the improvement in the fatigue strength of the steel in the 1990s. The hardening mechanism in the same specimens as the pioneering work was recently examined using a finite element simulation method. However, this work has not been completed for lack of experimental quenching cooling curves for the comparisons. In this study, the same experiments using 20mm diameter cylindrical specimens as those of the pioneering work were conducted to obtain cooling curves and hardness distributions for comparing simulated results. Experimental cooling curves showed a temperature recovery as predicted by the simulation. Also the inverse quench-hardening phenomena were found in the measured and simulated hardness distributions of the specimens. 展开更多
关键词 热处理 逆淬火硬化 轴承钢 计算机模拟
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EB病毒在结外NK/T细胞淋巴瘤中的预后价值:一项淮海淋巴瘤协作组的多中心回顾性研究 被引量:1
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作者 沈子园 胡灵灵 +6 位作者 张颢 苗雨青 贾韬 王玲 叶静静 朱太岗 桑威 《中国现代医学杂志》 CAS 北大核心 2023年第21期9-15,共7页
目的 基于倾向性评分逆处理概率加权(IPTW)法评估EB病毒(EBV)在结外NK/T细胞淋巴瘤患者中的预后价值。方法 收集2012年10月—2021年4月淮海淋巴瘤协作组中8家医疗机构初诊为结外NK/T细胞淋巴瘤且具有全血EBV-DNA数据的468例患者的临床... 目的 基于倾向性评分逆处理概率加权(IPTW)法评估EB病毒(EBV)在结外NK/T细胞淋巴瘤患者中的预后价值。方法 收集2012年10月—2021年4月淮海淋巴瘤协作组中8家医疗机构初诊为结外NK/T细胞淋巴瘤且具有全血EBV-DNA数据的468例患者的临床资料。采用IPTW法分析EBV载量对结外NK/T细胞淋巴瘤患者生存期的影响;采用Cox比例风险模型进行多因素分析;绘制Kaplan-Meier曲线,组间比较采用Log rank χ~2检验。结果 468例结外NK/T细胞淋巴瘤患者中,EBV-DNA阳性266例,EBV-DNA阴性202例。EBV-DNA阳性组和阴性组患者的5年OS分别为62.5%和89.2%,两组比较,经Log rank χ~2检验,差异有统计学意义(χ~2=42.900,P=0.000)。IPTW前,两组的美国东部肿瘤协作组(ECOG)活动状态(PS)评分(ECOG PS评分)、原发部位、CA分期、Ann Arbor分期、白蛋白、乳酸脱氢酶、治疗方案比较,差异均有统计学意义(P<0.05)。IPTW后,EBV-DNA阳性组和阴性组组间均衡,EBV-DNA阴性组患者5年OS为90.7%,而EBV-DNA阳性组患者5年OS为63.5%。Cox比例风险模型分析结果 显示,EBV-DNA阳性[■=4.244(95%CI:2.457,7.332)]、ECOG PS≥2分[■=2.020(95%CI:1.171,3.483)]是结外NK/T细胞淋巴瘤患者预后的不良影响因素(P<0.05)。结论 经IPTW法平衡混杂因素后,EBV-DNA阴性患者生存情况明显优于EBV-DNA阳性患者。 展开更多
关键词 结外NK/T细胞淋巴瘤 EB病毒 逆处理概率加权法
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谁是“双减”政策影响的目标群体?——参加校外学科培训的影响因素及效应分析 被引量:2
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作者 黄国英 范皑皑 《教育与经济》 CSSCI 北大核心 2023年第5期45-53,共9页
本研究基于中国家庭追踪调查2018年调查数据,使用Logit回归和倾向值逆概率加权(IPTW)模型评估“双减”政策对校外学科培训所影响的目标人群和对儿童学业成绩产生的可能影响。研究结果显示,儿童参加校外学科培训存在普遍性和阶层分化的... 本研究基于中国家庭追踪调查2018年调查数据,使用Logit回归和倾向值逆概率加权(IPTW)模型评估“双减”政策对校外学科培训所影响的目标人群和对儿童学业成绩产生的可能影响。研究结果显示,儿童参加校外学科培训存在普遍性和阶层分化的特征。参加校外学科培训对儿童的数学认知能力测验得分有轻微的正向提升作用,这一正向作用仅限于居住在城市或父亲学历在高中以上、数学成绩好等具有更高的参加学科培训倾向的儿童。通过将倾向值逆概率加权和复杂抽样设计结合分析,这一研究结果具备推论到全国总体的有效性。 展开更多
关键词 “双减”政策 学科培训 倾向值逆概率加权
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重型吊装场地换填垫层变形计算分析 被引量:1
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作者 郝增明 白晓宇 +6 位作者 桑松魁 张明义 张启军 林西伟 王立彬 张凯祥 蔺金龙 《科学技术与工程》 北大核心 2023年第29期12655-12662,共8页
以青岛市黄岛区的软弱地基为背景,通过现场试验和ABAQUS数值模拟相结合的方法,探讨重型吊装场地换填垫层后持力层变形计算问题。采用内插法对沉降计算经验系数进行修正以及反演瞬时沉降的地基弹性模量,并将修正的沉降结果和反演值与数... 以青岛市黄岛区的软弱地基为背景,通过现场试验和ABAQUS数值模拟相结合的方法,探讨重型吊装场地换填垫层后持力层变形计算问题。采用内插法对沉降计算经验系数进行修正以及反演瞬时沉降的地基弹性模量,并将修正的沉降结果和反演值与数值模拟结果进行比对,研究内插法优化程度及反演弹性模量的实用性。结果表明:内插法修正分层总和法中的沉降计算经验系数能使计算的沉降结果更加接近数值模拟结果,将反演的弹性模量在数值模拟中进行赋值,使模拟结果与静载试验结果相吻合,二者均能达到优化变形计算的目的。在重型吊装场地换填垫层的持力层变形计算中采用以上两种方法具有较强的实用性。研究结果可为类似地层的地基处理和吊装工程提供参考。 展开更多
关键词 地基处理 换填 变形 有限元模拟 反演弹性模量 重型吊装场地
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