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Heparin-binding protein as a predictor of mortality in patients with diabetes mellitus and community-acquired pneumonia in intensive care unit:a propensity score matched study
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作者 Yuhan Sun Baoqing Sun +3 位作者 Zhigang Ren Mingshan Xue Changju Zhu Qi Liu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第4期263-272,共10页
BACKGROUND:Patients with diabetes mellitus(DM)are vulnerable to community-acquired pneumonia(CAP),which have a high mortality rate.We aimed to investigate the value of heparin-binding protein(HBP)as a prognostic marke... BACKGROUND:Patients with diabetes mellitus(DM)are vulnerable to community-acquired pneumonia(CAP),which have a high mortality rate.We aimed to investigate the value of heparin-binding protein(HBP)as a prognostic marker of mortality in patients with DM and CAP.METHODS:This retrospective study included CAP patients who were tested for HBP at intensive care unit(ICU)admission from January 2019 to April 2020.Patients were allocated to the DM or non-DM group and paired with propensity score matching.Baseline characteristics and clinical outcomes up to 90 days were evaluated.The primary outcome was the 10-day mortality.Receiver operating characteristic(ROC)curves,Kaplan-Meier analysis,and Cox regression were used for statistical analysis.RESULTS:Among 152 enrolled patients,60 pairs were successfully matched.There was no significant difference in 10-day mortality,while more patients in the DM group died within 28 d(P=0.024)and 90 d(P=0.008).In the DM group,HBP levels at ICU admission were higher in 10-day non-survivors than in 10-day survivors(median 182.21[IQR:55.43-300]ng/ml vs.median 66.40[IQR:34.13-107.85]ng/mL,P=0.019),and HBP levels could predict the 10-day mortality with an area under the ROC curve of 0.747.The cut-off value,sensitivity,and specificity were 160.6 ng/mL,66.7%,and 90.2%,respectively.Multivariate Cox regression analysis indicated that HBP was an independent prognostic factor for 10-day(HR 7.196,95%CI:1.596-32.455,P=0.01),28-day(HR 4.381,95%CI:1.449-13.245,P=0.009),and 90-day mortality(HR 4.581,95%CI:1.637-12.819,P=0.004)in patients with DM.CONCLUSION:Plasma HBP at ICU admission was associated with the 10-day,28-day,and 90-day mortality,and might be a prognostic factor in patients with DM and CAP. 展开更多
关键词 Community-acquired pneumonia Diabetes mellitus Heparin-binding protein Propensity score match
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Facilely constructing ultrahigh lattice-matched CuZn_(5) epitaxial interface for dendrite-free Zn metal anode
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作者 Jin Cao Haiyang Wu +7 位作者 Yilei Yue Dongdong Zhang Biaoyang Li Ding Luo Lulu Zhang Jiaqian Qin Xinyu Zhang Xuelin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期671-680,共10页
Constructing a protective layer on Zn anode surface with high lattice matching to Zn(002)can facilitate preferential growth along the(002)crystal plane and suppress dendritic growth as well as interface side reactions... Constructing a protective layer on Zn anode surface with high lattice matching to Zn(002)can facilitate preferential growth along the(002)crystal plane and suppress dendritic growth as well as interface side reactions.Whereas most of protective layers are complex and costly,making commercial applications challenging.Herein,we introduce a facile method involving the addition of CuCl_(2) electrolyte additives to conventional electrolyte systems,which,through rapid displacement reactions and controlled electrochemical cycling,forms a CuZn_(5) alloy layer with 97.2%lattice matching to the(002)plane(CuZn_(5)@Zn),thus regulating the(002)plane epitaxial deposition.As a result,the symmetric cells with CuZn_(5)@Zn demonstrate an ultra-long cycle life of 3600 h at 1 mA cm^(-2).Under extreme conditions of high current density(20 m A cm^(-2))and high zinc utilization(DOD_(Zn)=50%),stable cycling performance is maintained for 220 and 350 h,respectively.Furthermore,the CuZn_(5)@Zn||NH_(4)V_(4)O_(10)full cell maintains a capacity of 120 m A h g^(-1)even after 10,000 cycles at a high current density of 10 A g^(-1).This work presents a facile and efficient strategy for constructing stable metal anode materials,with implications for the development of next-generation rechargeable batteries. 展开更多
关键词 Zn anode CuZn_(5)alloy Lattice matching DENDRITES Side reactions
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Comparison of endoscopic and laparoscopic resection of gastric gastrointestinal stromal tumors:A propensity score-matched study
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作者 Bin-Bin Gu Yan-Di Lu +3 位作者 Jin-Shun Zhang Zhen-Zhen Wang Xin-Li Mao Ling-Ling Yan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3694-3702,共9页
BACKGROUND Endoscopic resection(ER)and laparoscopic resection(LR)have been widely used for the treatment of non-metastatic gastric gastrointestinal stromal tumors(gGISTs)(2-5 cm),but there are no selection criteria fo... BACKGROUND Endoscopic resection(ER)and laparoscopic resection(LR)have been widely used for the treatment of non-metastatic gastric gastrointestinal stromal tumors(gGISTs)(2-5 cm),but there are no selection criteria for their application.AIM To provide a reference for the development of standardized treatment strategies for gGISTs.METHODS Clinical baseline characteristics,histopathological results,and short-term and long-term outcomes of patients who treated with ER or LR for gGISTs of 2-5 cm in Taizhou Hospital of Zhejiang Province from January 2014 to August 2022 were retrospectively reviewed.Propensity score matching(PSM)was employed to achieve balance in baseline characteristics of the two groups.RESULTS Among 206 patients,135 were in the ER group and 71 in the LR group.The ER group had significantly smaller tumors[3.5 cm(3.0-4.0 cm)vs 4.2 cm(3.3-5.0 cm),P<0.001]and different tumor locations(P=0.048).After PSM,59 pairs of patients were balanced.After matching,the baseline characteristics of the ER and LR groups did not differ significantly from each other.Compared with LR,ER had faster recovery of diet(P=0.046)and fewer postoperative symptoms(P=0.040).LR achieved a higher complete resection rate(P<0.001)and shorter operation time(P<0.001).No significant differences were observed in postoperative hospital stay(P=0.478),hospital costs(P=0.469),complication rates(P>0.999),pathological features(mitosis,P=0.262;National Institutes of Health risk classification,P=0.145),recurrence rates(P=0.476),or mortality rates(P=0.611).CONCLUSION Both ER and LR are safe and effective treatments for gGISTs.ER has less postoperative pain and faster recovery,while LR has a higher rate of complete resection. 展开更多
关键词 Gastrointestinal stromal tumor Endoscopic resection Laparoscopic resection Propensity score matching PROGNOSIS Complete resection
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Laparoscopic hepatectomy using indocyanine green attenuates postoperative inflammatory response for hepatocellular carcinoma:A propensity score matching analysis
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作者 Wei-Xun Wu Ming-Bin Huang +3 位作者 Mei-Xia Wang Li-Hua Chen Bo Hu Zhen-Bin Ding 《World Journal of Gastrointestinal Surgery》 2025年第1期193-202,共10页
BACKGROUND Improving the intraoperative and postoperative performance of laparoscopic hepatectomy was quite a challenge for liver surgeons.AIM To determine the benefits of indocyanine green(ICG)fluorescence imaging in... BACKGROUND Improving the intraoperative and postoperative performance of laparoscopic hepatectomy was quite a challenge for liver surgeons.AIM To determine the benefits of indocyanine green(ICG)fluorescence imaging in patients with hepatocellular carcinoma(HCC)who underwent laparoscopic hepatectomy during and after surgery.METHODS We retrospectively collected the clinicopathological data of 107 patients who successfully underwent laparoscopic hepatectomy at Zhongshan Hospital(Xiamen),Fudan University from June 2022 to June 2023.Whether using the ICG fluorescence imaging technique,we divided them into the ICG and non-ICG groups.To eliminate statistical bias,a 1:1 propensity score matching analysis was conducted.The comparison of perioperative outcomes,including inflammationrelated markers and progression-free survival,was analyzed statistically.RESULTS Intraoperatively,the ICG group exhibited lower blood loss,a shorter surgical time,lower hepatic inflow occlusion(HIO)frequency,and a shorter total HIO time.Postoperatively,the participation of ICG resulted in a shorter duration of hospitalization(6.5 vs 7.6 days,P=0.03)and postoperative inflammatory response attenuation(lower neutrophil-lymphocyte ratio on the first day after surgery and platelet-lymphocyte ratio on the third day,P<0.05).Although the differences were not significant,the levels of all inflammation-related markers were lower in the ICG group.The rates of postoperative complications and the survival analyses,including progression-free and overall survivals showed no significant difference between the groups.CONCLUSION The involvement of ICG fluorescence imaging may lead to improved perioperative outcomes,especially postoperative inflammatory response attenuation,and ultimately improve HCC patients’recovery after surgery. 展开更多
关键词 Hepatocellular carcinoma Laparoscopic hepatectomy Indocyanine green fluorescence Postoperative inflammatory response attenuation Propensity score matching analysis
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Efficacy-cost analysis of endoscopic mucosal resection and cold snare polypectomy:A propensity score matching analysis
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作者 Shi-Yi Zhang Ying-Chun Wang +2 位作者 Lei-Lei Liu Zhi-Heng Wang Xue-Mei Guan 《World Journal of Gastrointestinal Surgery》 2025年第2期77-86,共10页
BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences b... BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences between CSP and traditional endoscopic mucosal resection(EMR)for the treatment of intestinal polyps.AIM To compare the efficacy-cost of EMR and CSP in the treatment of intestinal polyps.METHODS A total of 100 patients with intestinal polyps were included in the retrospective data of our hospital from April 2022 to May 2023.According to the treatment methods,they were divided into EMR(n=46)group and CSP(n=54)group.The baseline data of the two groups were balanced by 1:1 propensity score matching(PSM),and the cost-effectiveness analysis was performed on the two groups after matching.The recurrence rate of the two groups of patients was followed up for 1 year,and they were divided into recurrence group and non-recurrence group according to whether they recurred.Multivariate logistic regression analysis was used to screen out the influencing factors affecting the recurrence of intestinal polyps after endoscopic resection.RESULTS Significant disparities were observed in the number of polyps and smoking background between the two groups before PSM(P<0.05).Following PSM,the number of polyps and smoking history were well balanced between the EMR and CSP groups.The direct cost incurred by the CSP group was markedly higher than that incurred by the EMR group.Concurrently,the cost-effectiveness ratio in the CSP group was substantially reduced when juxtaposed with that in the EMR group(P<0.05).Upon completion of the 1-year follow-up,the rate of recurrence after endoscopic intestinal polypectomy was 38.00%.Multivariate methods revealed that age≥60 years,male sex,number of polyps≥3,and pathological type of adenoma were risk factors for recurrence after endoscopic intestinal polypectomy(all P<0.05).CONCLUSION CSP was more cost-effective for the treatment of intestinal polyps.An age≥60 years,male sex,having a number of polyps≥3,and pathological type of adenoma are independent influencing factors for recurrence. 展开更多
关键词 Propensity score matching method Endoscopic mucosal resection Cold snare polypectomy Intestinal polyps Curative effect Cost analysis
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The Application of the Nonsplitting Perfectly Matched Layer in Numerical Modeling of Wave Propagation in Poroelastic Media 被引量:4
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作者 宋若龙 马俊 王克协 《Applied Geophysics》 SCIE CSCD 2005年第4期216-222,共7页
The nonsplitting perfectly matched layer (NPML) absorbing boundary condition (ABC) was first provided by Wang and Tang (2003) for the finite-difference simulation of elastic wave propagation in solids. In this p... The nonsplitting perfectly matched layer (NPML) absorbing boundary condition (ABC) was first provided by Wang and Tang (2003) for the finite-difference simulation of elastic wave propagation in solids. In this paper, the method is developed to extend the NPML to simulating elastic wave propagation in poroelastic media. Biot's equations are discretized and approximated to a staggered-grid by applying a fourth-order accurate central difference in space and a second-order accurate central difference in time. A cylindrical twolayer seismic model and a borehole model are chosen to validate the effectiveness of the NPML. The results show that the numerical solutions agree well with the solutions of the discrete wavenumber (DW) method. 展开更多
关键词 FINITE-DIFFERENCE numerical simulation absorbing boundary condition and perfectly matched layer.
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A study of perfectly matched layers for joint multicomponent reverse-time migration 被引量:3
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作者 杜启振 秦童 +1 位作者 朱钇同 毕丽飞 《Applied Geophysics》 SCIE CSCD 2010年第2期166-173,194,195,共10页
Reverse-time migration in finite space requires effective boundary processing technology to eliminate the artificial truncation boundary effect in the migration result.On the basis of the elastic velocity-stress equat... Reverse-time migration in finite space requires effective boundary processing technology to eliminate the artificial truncation boundary effect in the migration result.On the basis of the elastic velocity-stress equations in vertical transversely isotropic media and the idea of the conventional split perfectly matched layer(PML),the PML wave equations in reverse-time migration are derived in this paper and then the high order staggered grid discrete schemes are subsequently given.Aiming at the"reflections"from the boundary to the computational domain,as well as the effect of seismic event's abrupt changes at the two ends of the seismic array,the PML arrangement in reverse-time migration is given.The synthetic and real elastic,prestack,multi-component,reverse-time depth migration results demonstrate that this method has much better absorbing effects than other methods and the joint migration produces good imaging results. 展开更多
关键词 perfectly matched layer(PML) absorbing boundary reverse-time migration velocity-stress equation MULTI-COMPONENT
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A Novel Matched Filter Structure with Neuron MOS Devices 被引量:1
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作者 杨媛 余宁梅 高勇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第1期1-5,共5页
Based on the principle of the neuron MOS device,a novel matched filter structure which is easily realized by neuron MOS is presented and the details of circuit performance is analyzed.Compared to the conventional stru... Based on the principle of the neuron MOS device,a novel matched filter structure which is easily realized by neuron MOS is presented and the details of circuit performance is analyzed.Compared to the conventional structure,the number of circuit elements is decreased greatly for the same function.The test chip is fabricated in 0.35μm process,and the measured result shows that the system structure is feasible and effective. 展开更多
关键词 neuron MOS matched filter THRESHOLD
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Perfectly matched layer-absorbing boundary condition for finite-element time-domain modeling of elastic wave equations 被引量:3
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作者 赵建国 史瑞其 《Applied Geophysics》 SCIE CSCD 2013年第3期323-336,359,共15页
The perfectly matched layer (PML) is a highly efficient absorbing boundary condition used for the numerical modeling of seismic wave equation. The article focuses on the application of this technique to finite-eleme... The perfectly matched layer (PML) is a highly efficient absorbing boundary condition used for the numerical modeling of seismic wave equation. The article focuses on the application of this technique to finite-element time-domain numerical modeling of elastic wave equation. However, the finite-element time-domain scheme is based on the second- order wave equation in displacement formulation. Thus, the first-order PML in velocity-stress formulation cannot be directly applied to this scheme. In this article, we derive the finite- element matrix equations of second-order PML in displacement formulation, and accomplish the implementation of PML in finite-element time-domain modeling of elastic wave equation. The PML has an approximate zero reflection coefficients for bulk and surface waves in the finite-element modeling of P-SV and SH wave propagation in the 2D homogeneous elastic media. The numerical experiments using a two-layer model with irregular topography validate the efficiency of PML in the modeling of seismic wave propagation in geological models with complex structures and heterogeneous media. 展开更多
关键词 Absorbing boundary condition elastic wave equation perfectly matched layer finite-element modeling
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A study of damping factors in perfectly matched layers for the numerical simulation of seismic waves 被引量:3
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作者 杨皓星 王红霞 《Applied Geophysics》 SCIE CSCD 2013年第1期63-70,118,共9页
When simulating seismic wave propagation in free space, it is essential to introduce absorbing boundary conditions to eliminate reflections from artificially trtmcated boundaries. In this paper, a damping factor refer... When simulating seismic wave propagation in free space, it is essential to introduce absorbing boundary conditions to eliminate reflections from artificially trtmcated boundaries. In this paper, a damping factor referred to as the Gaussian dmping factor is proposed. The Gaussian damping factor is based on the idea of perfectly matched layers (PMLs). This work presents a detailed analysis of the theoretical foundations and advantages of the Gaussian damping factor. Additionally, numerical experiments for the simulation of seismic waves are presented based on two numerical models: a homogeneous model and a multi-layer model. The results show that the proposed factor works better. The Gaussian damping factor achieves a higher Signal-to-Noise Ratio (SNR) than previously used factors when using same number of PMLs, and requires less PMLs than other methods to achieve an identical SNR. 展开更多
关键词 simulation of seismic wave perfectly matched layer (PML) damping factor
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Case-matched comparison of laparoscopy-assisted and open distal gastrectomy for gastric cancer 被引量:15
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作者 Wei Wang Ke Chen +2 位作者 Xiao-Wu Xu Yu Pan Yi-Ping Mou 《World Journal of Gastroenterology》 SCIE CAS 2013年第23期3672-3677,共6页
AIM: To compare shortand long-term outcomes of laparoscopy-assisted and open distal gastrectomy for gastric cancer. METHODS: A retrospective study was performed by comparing the outcomes of 54 patients who underwent l... AIM: To compare shortand long-term outcomes of laparoscopy-assisted and open distal gastrectomy for gastric cancer. METHODS: A retrospective study was performed by comparing the outcomes of 54 patients who underwent laparoscopy-assisted distal gastrectomy (LADG) with those of 54 patients who underwent open distal gastrectomy (ODG) between October 2004 and October 2007. The patients' demographic data (age and gender), date of surgery, extent of lymphadenectomy, and differentiation and tumor-node-metastasis stage of the tumor were examined. The operative time, intraoperative blood loss, postoperative recovery, complications, pathological findings, and follow-up data were compared between the two groups.RESULTS: The mean operative time was significantly longer in the LADG group than in the ODG group (259.3 ± 46.2 min vs 199.8 ± 40.85 min; P < 0.05), whereas intraoperative blood loss and postoperative complications were significantly lower (160.2 ± 85.9 mL vs 257.8 ± 151.0 mL; 13.0% vs 24.1%, respectively, P < 0.05). In addition, the time to first flatus, time to initiate oral intake, and postoperative hospital stay were significantly shorter in the LADG group than in the ODG group (3.9 ± 1.4 d vs 4.4 ± 1.5 d; 4.6 ± 1.2 d vs 5.6 ± 2.1 d; and 9.5 ± 2.7 d vs 11.1 ± 4.1 d, respectively; P < 0.05). There was no significant difference between the LADG group and ODG group with regard to the number of harvested lymph nodes. The median followup was 60 mo (range, 5-97 mo). The 1-, 3-, and 5-year disease-free survival rates were 94.3%, 90.2%, and 76.7%, respectively, in the LADG group and 89.5%, 84.7%, and 82.3%, respectively, in the ODG group. The 1-, 3-, and 5-year overall survival rates were 98.0%, 91.9%, and 81.1%, respectively, in the LADG group and 91.5%, 86.9%, and 82.1%, respectively, in the ODG group. There was no significant difference between the two groups with regard to the survival rate. CONCLUSION: LADG is suitable and minimally invasive for treating distal gastric cancer and can achieve similar long-term results to ODG. 展开更多
关键词 STOMACH NEOPLASMS GASTRECTOMY LAPAROSCOPY Survival CASE matched study
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Perfectly Matched Layer for an Elastic Parabolic Equation Model in Ocean Acoustics 被引量:5
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作者 XU Chuanxiu ZHANG Haigang +3 位作者 PIAO Shengchun YANG Shi’e SUN Sipeng TANG Jun 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期57-64,共8页
The perfectly matched layer(PML) is an effective technique for truncating unbounded domains with minimal spurious reflections. A fluid parabolic equation(PE) model applying PML technique was previously used to analyze... The perfectly matched layer(PML) is an effective technique for truncating unbounded domains with minimal spurious reflections. A fluid parabolic equation(PE) model applying PML technique was previously used to analyze the sound propagation problem in a range-dependent waveguide(Lu and Zhu, 2007). However, Lu and Zhu only considered a standard fluid PE to demonstrate the capability of the PML and did not take improved one-way models into consideration. They applied a [1/1] Padé approximant to the parabolic equation. The higher-order PEs are more accurate than standard ones when a very large angle propagation is considered. As for range-dependent problems, the techniques to handle the vertical interface between adjacent regions are mainly energy conserving and single-scattering. In this paper, the PML technique is generalized to the higher order elastic PE, as is to the higher order fluid PE. The correction of energy conserving is used in range-dependent waveguides. Simulation is made in both acoustic cases and seismo-acoustic cases. Range-independent and range-dependent waveguides are both adopted to test the accuracy and efficiency of this method. The numerical results illustrate that a PML is much more effective than an artificial absorbing layer(ABL) both in acoustic and seismo-acoustic sound propagation modeling. 展开更多
关键词 ELASTIC PARABOLIC EQUATION perfectly matched LAYER artificial absorbing LAYER
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First-line pemetrexed-platinum doublet chemotherapy with or without bevacizumab in non-squamous non-small cell lung cancer: A real-world propensity score-matched study in China 被引量:5
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作者 Fei Qi Xingsheng Hu +4 位作者 Yutao Liu Zhijie Wang Jianchun Duan Jie Wang Mei Dong 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第5期749-758,共10页
Objective: To evaluate the efficacy and safety profile of first-line bevacizumab(Bev)-containing pemetrexedplatinum chemotherapy in a real-world Chinese cohort with advanced non-squamous non-small cell lung cancer(NS-... Objective: To evaluate the efficacy and safety profile of first-line bevacizumab(Bev)-containing pemetrexedplatinum chemotherapy in a real-world Chinese cohort with advanced non-squamous non-small cell lung cancer(NS-NSCLC).Methods: A total of 415 eligible patients with NS-NSCLC who received first-line pemetrexed-platinum chemotherapy at National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between February 2010 and September 2017 were reviewed retrospectively: 309 Bev(-) and 106 Bev(+) cases. Bev was administered at 7.5 mg/kg every 3 weeks in the Bev(+) group. To reduce the risk of a selection bias, a propensity score-matching(PSM) was conducted and 105 pairs of Bev(-) and Bev(+) cases were identified.Results: The median duration of follow-up was 15.8 months. The median progression-free survival(PFS) was prolonged significantly in the Bev(+) group than in the Bev(-) group in overall(9.8 vs. 7.8 months, P=0.006) and PSM pairs(9.8 vs. 6.6 months, P<0.001). Moreover, patients receiving maintenance therapy with pemetrexed plus Bev had longer PFS than those interrupted after induction chemotherapy, or those receiving mono-maintenance with pemetrexed(12.3 vs. 4.8 vs. 8.6 months;P<0.001). Multivariate analyses revealed Bev to be one of the favorable prognostic factors for PFS, along with the predictor of maintenance therapy.Conclusions: First-line induction and maintenance therapy with Bev(7.5 mg/kg every 3 weeks) combined with pemetrexed-platinum chemotherapy was efficacious and superior to non-Bev chemotherapy in Chinese patients with advanced NS-NSCLC. 展开更多
关键词 BEVACIZUMAB PEMETREXED non-squamous non-small cell lung cancer maintenance treatment propensity score matching
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A Uniaxial Optimal Perfectly Matched Layer Method for Time-harmonic Scattering Problems 被引量:5
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作者 YANG XIAO-YING MA FU-MING +1 位作者 ZHANG DE-YUE Du XIN-WEI 《Communications in Mathematical Research》 CSCD 2010年第3期255-268,共14页
We develop a uniaxial optimal perfectly matched layer (opt PML) method for solving the time-harmonic scattering problems by choosing a particular absorbing function with unbounded integral in a rectangular domain. W... We develop a uniaxial optimal perfectly matched layer (opt PML) method for solving the time-harmonic scattering problems by choosing a particular absorbing function with unbounded integral in a rectangular domain. With this choice, the solution of the optimal PML problem not only converges exponentially to the solution of the original scatting problem, but also is insensitive to the thickness of the PML layer for sufficiently small parameter ε0. Numerical experiments are included to illustrate the competitive behavior of the proposed optimal method. 展开更多
关键词 uniaxial optimal perfectly matched layer time-harmonic scattering CONVERGENCE
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An 8GHz Internally Matched AlGaN/GaN HEMT Power Amplifier with RC Stability Network
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作者 曾轩 陈晓娟 +8 位作者 刘果果 袁婷婷 陈中子 张辉 王亮 李诚瞻 庞磊 刘新宇 刘键 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1445-1448,共4页
8GHz 20W internally matched A1GaN/GaN HEMTs have been developed. The input and output matching net- works are realised with microstrip lines on a 0. 381mm thick alumina substrate. To improve the stability factor K of ... 8GHz 20W internally matched A1GaN/GaN HEMTs have been developed. The input and output matching net- works are realised with microstrip lines on a 0. 381mm thick alumina substrate. To improve the stability factor K of the device, a lossy RC network is used at the input of the device. The developed internally matched power amplifier module exhibits 43dBm (20W) power output with a 7.3dB linear gain,38.1% PAIE,and combined power efficiency of 70.6% at 8GHz. 展开更多
关键词 AlGaN/GaN HEMTs internally match power combining power amplifier
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Determinant of Low Birth Weight Infants: A Matched Case Control Study 被引量:3
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作者 Rosnah Sutan Mazlina Mohtar +1 位作者 Aimi Nazri Mahat Azmi Mohd Tamil 《Open Journal of Preventive Medicine》 2014年第3期91-99,共9页
Background: Low birth weight (LBW) is a well-known factor associated with neonatal mortality and has contributed to a range of poor health outcomes. Thus, the objective of this study was to determine factors associate... Background: Low birth weight (LBW) is a well-known factor associated with neonatal mortality and has contributed to a range of poor health outcomes. Thus, the objective of this study was to determine factors associated with LBW infants. Methods: A matched case control study was conducted in Universiti Kebangsaan Malaysia. Data of deliveries were obtained from Total Hospital Information System and medical records. All registered deliveries from January to June 2012 were used as sample populations. There were 180 pairs of cases and controls matched on babies’ gender. Fourteen variables were analyzed: maternal age, ethnicity, gravida, parity, gestational age, maternal booking weight, height and body mass index (BMI), history of low birth weight infants, birth interval, booking hemoglobin levels, hypertension, diabetes mellitus and mode of delivery. Results: Younger mother (t = 6.947, p < 0.001), lower booking BMI (t = 3.067, p = 0.002), prematurity (t = 12.324, p < 0.001), history of LBW infants (OR = 3.0, p = 0.001), LSCS (OR = 0.06, p = 0.001) and current hypertension (OR = 3.1, p = 0.008) were found significant in bivariate analysis. Multivariable conditional logistic regression identified younger maternal age (AOR = 2.9, 95% CI = 1.86 -4.51, p 13.58, p = 0.045), prematurity (AOR = 2.4, 95% CI = 1.79 -3.26, p < 0.001), and current hypertension (AOR = 4.5, 95% CI = 1.06 -19.22, p = 0.041) as significant factors associated with LBW infants. Conclusion: Younger maternal age, history of LBW infants, prematurity and hypertension have been recognized as predictors of LBW infants. The importance of pre-pregnancy screening, early antenatal booking and proper identification of high risk-mother needs to be strengthened and enforced in effort to reduce incidence of LBW infants. 展开更多
关键词 Low BIRTH WEIGHT MATERNAL FACTORS matched CASE Control
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A high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi earthquake sequence, Yunnan, China: Application of AI picker and matched filter 被引量:12
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作者 Yijian Zhou Abhijit Ghosh +3 位作者 Lihua Fang Han Yue Shiyong Zhou Youjin Su 《Earthquake Science》 2021年第5期390-398,共9页
We present a high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi sequence.The catalog has a time range of 2021-05-01 to 2021-05-28,and contains~8,000 well located events.It captures the features of t... We present a high-resolution seismic catalog for the 2021 M_(S)6.4/M_(W)6.1 Yangbi sequence.The catalog has a time range of 2021-05-01 to 2021-05-28,and contains~8,000 well located events.It captures the features of the whole foreshock sequence and the early aftershocks.We designed a detection strategy incorporating both an artificial intelligent(AI)picker and a matched filter algorithm.Here,we adopt a hybrid AI method incorporating convolutional and recurrent neural network(CNN&RNN)for event detection and phase picking respectively(i.e.CERP),a light-weight AI picker that can be trained with small volume of data.CERP is first trained with detections from a STA/LTA and Kurtosis-based method called PAL,and then construct a rather complete template set of~4,000 events.Finally,the matched filter algorithm MESS augments the initial detections and measures differential travel times with cross-correlation,which finally results in precise relocation.This process gives 9,026 detections,among which 7,943 events can be well relocated.The catalog shows as expected power-law distribution of frequency magnitude and reveals detailed pattern of seismicity evolution.The main features are:(1)the foreshock sequence images simple fault geometry with consistent strike,but also show a variable event depth along strike;(2)the mainshock ruptures the same fault of the foreshock sequence and activate conjugate faults further to the southeast;(3)complex seismicity are developed in the post-seismic period,indicating complex triggering mechanisms.Thus,our catalog provides a reliable basis for further investigations,such as b-value studies,rupture process,and triggering relations. 展开更多
关键词 Yangbi earthquake seismic catalog earthquake detection AI picker matched filter.
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Perfectly matched layer implementation for ADI-FDTD in dispersive media 被引量:2
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作者 Wang Yu Yuan Naichang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期80-84,共5页
Alternating direction implicit finite difference time domain (ADI-FDTD) method is unconditionally stable and the maximum time step is not limited by the Courant stability condition, but rather by numerical error. Co... Alternating direction implicit finite difference time domain (ADI-FDTD) method is unconditionally stable and the maximum time step is not limited by the Courant stability condition, but rather by numerical error. Compared with the conventional FDTD method, the time step of ADI-FDTD can be enlarged arbitrarily and the CPU cost can be reduced. 2D perfectly matched layer (PML) absorbing boundary condition is proposed to truncate computation space for ADI-FDTD in dispersive media using recursive convolution(RC) method and the 2D PML formulations for dispersive media are derived. ADI-FDTD formulations for dispersive media can be obtained from the simplified PML formulations. The scattering of target in dispersive soil is simulated under sine wave and Gaussian pulse excitations and numerical results of ADI-FDTD with PML are compared with FDTD. Good agreement is observed. At the same time the CPU cost for ADI-FDTD is obviously reduced. 展开更多
关键词 perfectly matched layer alternating direction implicit finite difference time domain dispersive media
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Borehole-GPR numerical simulation of full wave field based on convolutional perfect matched layer boundary 被引量:7
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作者 朱自强 彭凌星 +1 位作者 鲁光银 密士文 《Journal of Central South University》 SCIE EI CAS 2013年第3期764-769,共6页
The absorbing boundary is the key in numerical simulation of borehole radar.Perfect match layer(PML) was chosen as the absorbing boundary in numerical simulation of GPR.But CPML(convolutional perfect match layer) appr... The absorbing boundary is the key in numerical simulation of borehole radar.Perfect match layer(PML) was chosen as the absorbing boundary in numerical simulation of GPR.But CPML(convolutional perfect match layer) approach that we have chosen has the advantage of being media independent.Beginning with the Maxwell equations in a two-dimensional structure,numerical formulas of finite-difference time-domain(FDTD) method with CPML boundary condition for transverse electric(TE) or transverse magnetic(TM) wave are presented in details.Also,there are three models for borehole-GPR simulation.By analyzing the simulation results,the features of targets in GPR are obtained,which can provide a better interpretation of real radar data.The results show that CPML is well suited for the simulation of borehole-GPR. 展开更多
关键词 borehole-GPR numerical simulation convolutional perfect match layer finite-difference time-domain method
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Short-term efficacy of robotic and laparoscopic spleen-preserving splenic hilar lymphadenectomy via Huang’s three-step maneuver for advanced upper gastric cancer: Results from a propensity scorematched study 被引量:2
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作者 Jia-Bin Wang Zhi-Yu Liu +14 位作者 Qi-Yue Chen Qing Zhong Jian-Wei Xie Jian-Xian Lin Jun Lu Long-Long Cao Mi Lin Ru-Hong Tu Ze-Ning Huang Ju-Li Lin Hua-Long Zheng Si-Jin Que Chao-Hui Zheng Chang-Ming Huang Ping Li 《World Journal of Gastroenterology》 SCIE CAS 2019年第37期5641-5654,共14页
BACKGROUND Robotic surgery has been considered to be significantly better than laparoscopic surgery for complicated procedures.AIM To explore the short-term effect of robotic and laparoscopic spleen-preserving splenic... BACKGROUND Robotic surgery has been considered to be significantly better than laparoscopic surgery for complicated procedures.AIM To explore the short-term effect of robotic and laparoscopic spleen-preserving splenic hilar lymphadenectomy(SPSHL)for advanced gastric cancer(GC)by Huang’s three-step maneuver.METHODS A total of 643 patients who underwent SPSHL were recruited from April 2012 to July 2017,including 35 patients who underwent robotic SPSHL(RSPSHL)and 608 who underwent laparoscopic SPSHL(LSPSHL).One-to-four propensity score matching was used to analyze the differences in clinical data between patients who underwent robotic SPSHL and those who underwent laparoscopic SPSHL.RESULTS In all,175 patients were matched,including 35 patients who underwent RSPSHL and 140 who underwent LSPSHL.After matching,there were no significant differences detected in the baseline characteristics between the two groups.Significant differences in total operative time,estimated blood loss(EBL),splenic hilar blood loss(SHBL),splenic hilar dissection time(SHDT),and splenic trunk dissection time were evident between these groups(P<0.05).Furthermore,no significant differences were observed between the two groups in the overall noncompliance rate of lymph node(LN)dissection(62.9%vs 60%,P=0.757),number of retrieved No.10 LNs(3.1±1.4 vs 3.3±2.5,P=0.650),total number of examined LNs(37.8±13.1 vs 40.6±13.6,P=0.274),and postoperative complications(14.3%vs 17.9%,P=0.616).A stratified analysis that divided the patients receiving RSPSHL into an early group(EG)and a late group(LG)revealed that the LG experienced obvious improvements in SHDT and length of stay compared with the EG(P<0.05).Logistic regression showed that robotic surgery was a significantly protective factor against both SHBL and SHDT(P<0.05).CONCLUSION RSPSHL is safe and feasible,especially after overcoming the early learning curve,as this procedure results in a radical curative effect equivalent to that of LSPSHL. 展开更多
关键词 Advanced gastric cancer ROBOTIC surgery LAPAROSCOPIC surgery Dissection of SPLENIC HILAR lymph node Propensity score matching Huang’s three-step MANEUVER
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