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Clinical effect of laparoscopic radical resection of colorectal cancer based on propensity score matching
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作者 Yang Liu Xian-Xue Wang +3 位作者 Yu-Lin Li wen-tao he Hong Li Hua Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期124-133,共10页
BACKGROUND The incidence of colorectal cancer(CRC)is increasing annually.Laparoscopic radical resection of CRC is a minimally invasive procedure preferred in clinical practice.AIM To investigate the clinical effect of... BACKGROUND The incidence of colorectal cancer(CRC)is increasing annually.Laparoscopic radical resection of CRC is a minimally invasive procedure preferred in clinical practice.AIM To investigate the clinical effect of laparoscopic radical resection of CRC on the basis of propensity score matching(PSM).METHODS The clinical data of 100 patients who received inpatient treatment for CRC at Changde Hospital,Xiangya School of Medicine,Central South University(The First People’s Hospital of Changde City)were analyzed retrospectively.The control group included patients who underwent open surgery(n=43),and those who underwent laparoscopic surgery formed the observation group(n=57).The baseline information of both groups was equipoised using 1×1 PSM.Differences in the perioperative parameters,inflammatory response,immune function,degree of pain,and physical status between the groups were analyzed.RESULTS Thirty patients from both groups were successfully matched.After PSM,baseline data showed no statistically significant differences between the groups:(1)Periop-erative parameters:The observation group had a longer surgery time,less intra-operative blood loss,earlier first ambulation and first anal exhaust times,and shorter gastric tube indwelling time than the control group;(2)Inflammatory response:24 h after surgery,the levels of interleukin-6(IL-6),C-reactive protein(CRP),and tumor necrosis factor-α(TNF-α)between groups were higher than preoperatively.IL-6,CRP,and TNF-αlevels in the observation group were lower than in the control group;(3)Immune function:At 24 h after surgery,counts of CD4-positive T-lymphocytes(CD4+)and CD4+/CD8-positive T-lymphocytes(CD8+)in both groups were lower than those before surgery,whereas CD8+was higher than that before surgery.At 24 h after surgery,both CD4+counts and CD4+/CD8+in the observation group were higher than those in the control group,whereas CD8+counts were lower;(4)Degree of pain:The visual analog scale scores in the observation group were lower than those in the control group at 24 and 72 h after surgery;and(5)Physical status:One month after surgery,the Karnofsky performance score in the observation group was higher than that in the control group.CONCLUSION Laparoscopic radical resection of CRC has significant benefits,such as reducing postoperative pain and postoperative inflammatory response,avoiding excessive immune inhibition,and contributing to postoperative recovery. 展开更多
关键词 Colorectal cancer LAPAROSCOPIC Open surgery Inflammatory reaction Immune function Propensity score
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Sensitivity of seismic attenuation and dispersion to dynamic elastic interactions of connected fractures: Quasi-static finite element modeling study 被引量:2
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作者 Yan-Xiao He wen-tao he +8 位作者 Meng-Fan Zhang Jia-Liang Zhang Wei-Hua Liu Xiao-Yi Ma Gen-Yang Tang Shang-Xu Wang Guo-Fa Li Jun-Zhou Liu Xiang-Long Song 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期177-198,共22页
Prediction of seismic attenuation and dispersion that are inherently sensitive to hydraulic and elastic properties of the medium of interest in the presence of mesoscopic fractures and pores,is of great interest in th... Prediction of seismic attenuation and dispersion that are inherently sensitive to hydraulic and elastic properties of the medium of interest in the presence of mesoscopic fractures and pores,is of great interest in the characterization of fractured formations.This has been very difficult,however,considering that stress interactions between fractures and pores,related to their spatial distributions,tend to play a crucial role on affecting overall dynamic elastic properties that are largely unexplored.We thus choose to quantitatively investigate frequency-dependent P-wave characteristics in fractured porous rocks at the scale of a representative sample using a numerical scale-up procedure via performing finite element modelling.Based on 2-D numerical quasi-static experiments,effects of fracture and fluid properties on energy dissipation in response to wave-induced fluid flow at the mesoscopic scale are quantified via solving Biot's equations of consolidation.We show that numerical results are sensitive to some key characteristics of probed synthetic rocks containing unconnected and connected fractures,demonstrating that connectivity,aperture and inclination of fractures as well as fracture infills exhibit strong impacts on the two manifestations of WIFF mechanisms in the connected scenario,and on resulting total wave attenuation and phase velocity.This,in turn,illustrates the importance of these two WIFF mechanisms in fractured rocks and thus,a deeper understanding of them may eventually allow for a better characterization of fracture systems using seismic methods.Moreover,this presented work combines rock physics predictions with seismic numerical simulations in frequency domain to illustrate the sensitivity of seismic signatures on the monitoring of an idealized geologic CO_(2) sequestration in fractured reservoirs.The simulation demonstrates that these two WIFF mechanisms can strongly modify seismic records and hence,indicating that incorporating the two energy dissipation mechanisms in the geophysical interpretation can potentially improving the monitoring and surveying of fluid variations in fractured formations. 展开更多
关键词 Attenuation and dispersion Rock physics Fractured media Frequency dependence Numerical study
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9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物衍生物阻燃聚乳酸的性能研究 被引量:15
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作者 张通 龙丽娟 +3 位作者 何文涛 何敏 秦舒浩 于杰 《高分子学报》 SCIE CAS CSCD 北大核心 2019年第1期71-81,I0004,共12页
通过甲醛与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)反应合成出含羟基的DOPO衍生物9,10-二氢-9-氧杂-10-磷杂菲-10-甲醇10-氧化物(ODOPM).采用傅里叶变换红外光谱(FTIR),核磁共振谱(1HNMR,31P-NMR)以及质谱分析(MS)确定了其结构,同... 通过甲醛与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)反应合成出含羟基的DOPO衍生物9,10-二氢-9-氧杂-10-磷杂菲-10-甲醇10-氧化物(ODOPM).采用傅里叶变换红外光谱(FTIR),核磁共振谱(1HNMR,31P-NMR)以及质谱分析(MS)确定了其结构,同时研究了ODOPM对聚乳酸(PLA)阻燃性能与热性能的影响,并与10-(2,5-二羟基苯基)-10H-9-氧杂-10-磷杂菲-10-氧化物(DOPO-HQ)进行了比较.通过热重分析(TG)、氧指数(LOI)、垂直燃烧(UL-94)和锥形量热(CCT)等研究了2种阻燃剂对PLA阻燃性能及热降解行为的影响,发现2种阻燃剂都能降低材料的热释放峰值(PHRR),提高复合材料的热稳定性和残炭量,然而PLA/ODOPM相对于PLA/DOPO-HQ具有更高的氧指数和燃烧等级. PLA加入5%的ODOPM时就能达到V-0级,加入15%时,氧指数能达到34.4%,而DOPO-HQ加入量为15%时才能达到V-0,LOI值也仅仅28.8%.扫描电镜和拉曼对炭层的分析表明DOPO-HQ复合材料能够形成更加完整致密的炭层,因此具有更好的固相阻燃作用,此外TG-FTIR表明2种阻燃剂都能起到气相阻燃作用. X射线能量色谱(EDS)发现2种复合材料炭层中具有较高的P含量,这可能是炭层中形成了大量的聚磷酸酯.最后流变分析表明ODOPM会降低PLA的复数黏度,且PLA/ODOPM黏度远低于PLA/DOPO-HQ. 展开更多
关键词 阻燃 聚乳酸 9 10-二氢-9-氧杂-10-磷杂菲-10-甲醇10-氧化物(ODOPM) 10-(2 5-二羟基苯基)-10H-9-氧杂-10-磷杂菲-10-氧化物(DOPO-HQ)
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氨基碳纳米管/DOPO衍生物的协效阻燃及其对尼龙6性能的影响 被引量:9
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作者 王欣欣 何文涛 +3 位作者 徐国敏 龙丽娟 黄伟江 于杰 《高分子学报》 SCIE CAS CSCD 北大核心 2019年第4期419-428,共10页
将DOPO衍生物(DIDOPO)和氨基碳纳米管(MWCNTs)以一定的比例进行复配,添加到尼龙6(PA6)中熔融共混制得复合材料.运用万能试验机、热重分析仪、示差扫描量热仪、锥形量热仪及扫描电镜测试了各样本的力学性能、热稳定性、结晶性以及燃烧性... 将DOPO衍生物(DIDOPO)和氨基碳纳米管(MWCNTs)以一定的比例进行复配,添加到尼龙6(PA6)中熔融共混制得复合材料.运用万能试验机、热重分析仪、示差扫描量热仪、锥形量热仪及扫描电镜测试了各样本的力学性能、热稳定性、结晶性以及燃烧性能,并观察了炭层形貌.测试结果表明,加入MWCNTs后,复合材料的拉伸强度显著增强,与PA6/DIDOPO复合材料相比,其拉伸强度平均提升了55%.从非等温结晶曲线可以看出,加入MWCNTs后PA6复合材料的结晶初始温度(Tonset)和结晶峰温(Tc)都有明显提高,但由于MWCNTs的异相成核作用,结晶度降低.此外,锥形量热测试表明,当MWCNTs的添加量为2 wt%时,其热释放速率峰值(PHRR)为367.28 kW/m2,较纯PA6降低了58.9%.扫描电镜和拉曼测试分析表明MWCNTs的加入促进了致密结构炭层的形成,与DIDOPO有协效阻燃的作用. 展开更多
关键词 氨基碳纳米管 DOPO衍生物 尼龙6 热稳定性 协效阻燃
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