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A new production component method for natural gas development planning
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作者 Fanliao Wang Jiangchen Han +4 位作者 Shucheng Liu Yanqing Liu Kun Su jing du Liru Wang 《Energy Geoscience》 EI 2024年第1期283-292,共10页
Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction ... Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction of production.In this new method,the annual production of old and new wells is predicted by year first and then is summed up to yield the production for the planning period.It shows that the changes in the production of old wells in old blocks can be fitted and predicted using the vapor pressure model(VPM),with precision of 80%e95%,which is 6.6%e13.2%higher than that of other life cycle models.Furthermore,a new production prediction process and method for new wells have been established based on this life cycle model to predict the production of medium-to-shallow gas reservoirs in western Sichuan Basin,with predication error of production rate in 2021 and 2022 being 6%and 3%respectively.The new method can be used to guide the medium-and long-term planning or annual scheme preparation for gas development.It is also applicable to planning for large single gas blocks that require continuous infill drilling and adjustment to improve gas recovery. 展开更多
关键词 Production component method Production prediction Life cycle model Gas development planning Western Sichuan Basin
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Production forecasting methods for different types of gas reservoirs
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作者 Fanliao Wang Shucheng Liu +5 位作者 Ying Jia Anrong Gao Kun Su Yanqing Liu jing du Liru Wang 《Energy Geoscience》 EI 2024年第3期275-283,共9页
Hydrocarbon production in oil and gas fields generally progresses through stages of production ramp-up,plateau(peak),and decline during field development,with the whole process primarily modeled and forecasted using l... Hydrocarbon production in oil and gas fields generally progresses through stages of production ramp-up,plateau(peak),and decline during field development,with the whole process primarily modeled and forecasted using lifecycle models.SINOPEC's conventional gas reservoirs are dominated by carbonates,low-permeability tight sandstone,condensate,volcanic rocks,and medium-to-high-permeability sandstone.This study identifies the optimal production forecasting models by comparing the fitting coefficients of different models and calculating the relative errors in technically recoverable reserves.To improve forecast precision,it suggests substituting exponential smoothing method-derived predictions for anomalous data caused by subjective influences like market dynamics and maintenance activities.The preferred models for carbonate gas reservoir production forecasts are the generalized Weng's,Beta,Class-I generalized mathematical,and Hu-Chen models.The Vapor pressure and Beta models are optimal for forecasting the annual productivity of wells(APW)from gas-bearing low-permeability tight sandstone reservoirs.The Wang-Li,Beta,and Yu QT tb models are apt for moderate-to-small-reserves,single low-permeability tight sandstone gas reservoirs.The Rayleigh,Hu-Chen,and generalized Weng's models are suitable for condensate gas reservoirs.For medium-to-high-permeability sandstone gas reservoirs,the lognormal,generalized gamma,and Beta models are recommended. 展开更多
关键词 Production prediction Life cycle model Carbonate gas reservoir Low-permeability tight sandstone gas reservoir
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Catheter ablation for atrial fibrillation is associated with reduced risk of mortality in the elderly:a prospective cohort study and propensity score analysis 被引量:5
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作者 Xin SU Xin du +13 位作者 Shang-Xin LU Chao JIANG jing du Shi-Jun XIA Zhao-Jie DONG Zhao-Xu JIA De-Yong LONG Cai-Hua SANG Ri-Bo TANG Nian LIU Song-Nan LI Rong BAI Jian-Zeng DONG Chang-Sheng MA 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第12期740-749,共10页
Background It is unclear whether catheter ablation(CA)for atrial fibrillation(AF)affects the long-term prognosis in the elderly.This study aims to evaluate the relationship between CA and long-term outcomes in elderly... Background It is unclear whether catheter ablation(CA)for atrial fibrillation(AF)affects the long-term prognosis in the elderly.This study aims to evaluate the relationship between CA and long-term outcomes in elderly patients with AF.Methods Patients more than 75 years old with non-valvular AF were prospectively enrolled between August 2011 and December 2017 in the Chinese Atrial Fibrillation Registry Study.Participants who underwent CA at baseline were propensity score matched(1:1)with those who did not receive CA.The outcome events included all-cause mortality,cardiovascular mortality,stroke/transient ischemic attack(TIA),and cardiovascular hospitalization.Results Overall,this cohort included 571 ablated patients and 571 non-ablated patients with similar characteristics on 18 dimensions.During a mean follow-up of 39.75±19.98 months(minimum six months),24 patients died in the ablation group,compared with 60 deaths in the non-ablation group[hazard ratio(HR)=0.49,95%confidence interval(CI):0.30-0.79,P=0.0024].Besides,6 ablated and 29 non-ablated subjects died of cardiovascular disease(HR=0.25,95%CI:0.11-0.61,P=0.0022).A total of 27 ablated and 40 non-ablated patients suffered stroke/TIA(HR=0.79,95%CI:0.48-1.28,P=0.3431).In addition,140 ablated and 194 non-ablated participants suffered cardiovascular hospitalization(HR=0.84,95%CI:0.67-1.04,P=0.1084).Subgroup analyses according to gender,type of AF,time since onset of AF,and anticoagulants exposure in initiation did not show significant heterogeneity.Conclusions In elderly patients with AF,CA may be associated with a lower incidence of all-cause and cardiovascular mortality. 展开更多
关键词 Atrial fibrillation Catheter ablation MORTALITY STROKE The elderly
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Progress of electrochemical CO_(2)reduction reactions over polyoxometalate-based materials 被引量:3
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作者 jing du Yuan-Yuan Ma +2 位作者 Huaqiao Tan Zhen-Hui Kang Yangguang Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第6期920-937,共18页
Electrochemical CO_(2)reduction to value-added fuels and chemicals is recognized as a promising strategy to alleviate energy shortages and global warming owing to its high efficiency and economic feasibility.Recently,... Electrochemical CO_(2)reduction to value-added fuels and chemicals is recognized as a promising strategy to alleviate energy shortages and global warming owing to its high efficiency and economic feasibility.Recently,understanding the activity origin,selectivity regulation,and reaction mechanisms of CO_(2)reduction reactions(CO_(2)RRs)has become the focus of efficient electrocatalyst design.Polyoxometalates(POMs),a unique class of nanosized metal-oxo clusters,are promising candidates for the development of efficient CO_(2)RR electrocatalysts and,owing to their well-defined structure,remarkable electron/proton storage and transfer ability,and capacities for adsorption and activation of CO_(2),are ideal models for investigating the activity origin and reaction mechanisms of CO_(2)RR electrocatalysts.In this review,we focus on the activity origin and mechanism of CO_(2)RRs and survey recent advances that were achieved by employing POMs in electrocatalytic CO_(2)RRs.We highlight the significant roles of POMs in the electrocatalytic CO_(2)RR process and the main factors influencing selectivity regulation and catalytic CO_(2)RR performance,including the electrolyte,electron-transfer process,and surface characteristics.Finally,we offer a perspective of the advantages and future challenges of POM-based materials in electrocatalytic CO_(2)reduction that could inform new advancements in this promising research field. 展开更多
关键词 POLYOXOMETALATE ELECTROCATALYSIS CO_(2)reduction Electron transfer Mechanism
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Electroacupuncture induces acute changes in cerebral cortical mi RNA profile, improves cerebral blood flow and alleviates neurological deficits in a rat model of stroke 被引量:22
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作者 Hai-zhen Zheng Wei Jiang +6 位作者 Xiao-feng Zhao jing du Pan-gong Liu Li-dan Chang Wen-bo Li Han-tong Hu Xue-min Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第12期1940-1950,共11页
Electroacupuncture has been shown to improve cerebral blood flow in animal models of stroke. However, it is unclear whether electroacupuncture alters mi RNA expression in the cortex. In this study, we examined changes... Electroacupuncture has been shown to improve cerebral blood flow in animal models of stroke. However, it is unclear whether electroacupuncture alters mi RNA expression in the cortex. In this study, we examined changes in the cerebral cortical mi RNA profile, cerebral blood flow and neurological function induced by electroacupuncture in a rat model of stroke. Electroacupuncture was performed at Renzhong(GV26) and Neiguan(PC6), with a frequency of 2 Hz, continuous wave, current intensity of 3.0 m A, and stimulation time of 1 minute. Electroacupuncture increased cerebral blood flow and alleviated neurological impairment in the rats. mi RNA microarray profiling revealed that the vascular endothelial growth factor signaling pathway, which links cell proliferation with stroke, was most significantly affected by electroacupuncture. Electroacupuncture induced changes in expression of rno-mi R-206-3p, rno-mi R-3473, rno-mi R-6216 and rno-mi R-494-3p, and these changes were confirmed by quantitative real-time polymerase chain reaction. Our findings suggest that changes in cell proliferation-associated mi RNA expression induced by electroacupuncture might be associated with the improved cerebral blood supply and functional recovery following stroke. 展开更多
关键词 nerve regeneration stroke middle cerebral artery occlusion electroacupuncture mi RNA cerebral blood flow Neiguan(PC6) Renzhong(GV26) neural regeneration
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Observational results of MUSER during 2014–2019 被引量:1
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作者 Ming-Hui Zhang Yin Zhang +15 位作者 Yi-Hua Yan Wei Wang Lin-Jie Chen Cheng-Ming Tan Su-Li Ma jing Huang Xing-Yao Chen Bao-Lin Tan Zhichao Zhou Fei Liu Li-Hong Geng Sha Li jing du Cang Su Zhi-Jun Chen Jun Cheng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第11期127-138,共12页
The solar radio signal that can be received by the ground-based telescopes covers a wide frequency range,allowing us to monitor the complex physical processes occurred from the solar surface to the vast interplanetary... The solar radio signal that can be received by the ground-based telescopes covers a wide frequency range,allowing us to monitor the complex physical processes occurred from the solar surface to the vast interplanetary space.MingantU SpEctral Radioheliograph(MUSER),as the latest generation of solar dedicated radio spectral-imaging instrument in the centimeter-decimeter wavelengths,has accumulated a large number of observational data since its commissioning observation in 2014.This paper presents the main observational results identified by MUSER from 2014 to 2019,including the quiet Sun and 94 solar radio burst events.We find that there are 81 events accompanied with Geostationary Operational Environmental Satellites(GOES)soft X-ray(SXR)flares,among which the smallest flare class is B1.0.There are 13 events without accompanying any recorded flares,among which the smallest SXR intensity during the radio burst period is equivalent to level-A.The main characteristics of all radio burst events are presented,which shows the powerful ability of MUSER to capture the valuable information of the solar non-thermal processes and the importance for space weather.This work also provides a database for further in-depth research. 展开更多
关键词 Sun:radio radiation Sun:activity Sun:flares methods:observational
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Overexpression of Myocardin-related transcription factor-A attenuated middle cerebral artery occlusion/reperfusion-induced apoptosis via the Mcl-1/Cyt C/cleaved caspase 3 pathway 被引量:1
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作者 Zhi-Jun Yu jing du +8 位作者 Wei Zhang Shu-Qi Zhao Wei Dong Shi-Qiang Xu Ling Hu Zhen-Li Min Qiong Yuan Chunxiang Zhang Xia-Min Hu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第6期199-209,共11页
To investigate the effect of Myocardin related transcription factor A(MRTF-A)on apoptosis induced by ischemic/reperfusion(I/R),middle cerebral artery occlusion/reperfusion(MCAO/R)in rats were applied to mimic I/R.The ... To investigate the effect of Myocardin related transcription factor A(MRTF-A)on apoptosis induced by ischemic/reperfusion(I/R),middle cerebral artery occlusion/reperfusion(MCAO/R)in rats were applied to mimic I/R.The neurological deficit score,cerebral infarct size,cortical neuron apoptosis and cleaved caspase 3 level were evaluated to determine the effect and the level of apoptosis by TTC straining,terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)straining,Western blot and immunofuorescence staining.The myeloid cell leukemia-1(Mcl-1)expression,release of cytochrome C(Cyt C)and its colocalization with apoptotic pro-tease activating factor-1(Apaf-1)were analyzed by quantitative real-time PCR(qRT-PCR),Western blot,and immunofuorescence staining.The results showed that MRTF-A over-expression could decrease the neurological deficit score and reduce cerebral infarct size(P<0.01 versus Sham).In the MRTF-A-I/R group,TUNEL-positive cells and apoptosis ratio(%)(51.61±6.17%)were significantly decreased compared to the Neg-I/R group(76.45±8.77%)at 24 h reperfusion.Meanwhile,the cleaved caspase 3 expression revealed a similar trend while the expression of Mcl-1 was the opposite.Moreover,MRTF-A overexpression significantly enhanced Mcl-1 fAuorescence intensity,which up-regulated the mRNA and protein level(P<0.05or P<0.01 versus Neg-I/R).Furthermore,MRTF-A overexpression markedly inhibited the release of Cyt C,and decreased the colocalization with Apaf-1 in the cytoplasm(P<0.05 or P<0.01.versus Neg-I/R).All the data indicated that MRTF-A overexpression could improve the neu-rological function against cerebral I/R-induced apoptosis since underlying mechanism might be involved in the Mc-1/Cyt C/cleaved caspase 3 signaling pathway. 展开更多
关键词 Stroke animal model immunofuorescence staining laser scanning confocal microscope
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Effects of different anesthesia depth on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients with radical operation for gastric carcinoma 被引量:1
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作者 duo-Zhi Wu Hai Xie +4 位作者 Jian Liu jing du Tie-Jun Li Jian-Jun Ren Zhen-Ming Dong 《Journal of Hainan Medical University》 2017年第9期143-146,共4页
Objective:To observe the effects of different anesthesia depths on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients underwent radical gastrectomy.Methods: A total o... Objective:To observe the effects of different anesthesia depths on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients underwent radical gastrectomy.Methods: A total of eighty seven elderly patients undergoing radical gastrectomy were enrolled in this study. Continuous infusion of propofol and remifentanil for anesthesia and maintenance of propofol were divided into two groups: BIS-I (BIS: 45-55) and BIS-II (BIS: 55-65) by adusting the doses of propofol. The data were recorded as following, thewhole dosage of propofol, the time of extubation and the score of VAS. The level of plasma cortisol was finished at the time of incision and tracheal intubation. MMSE scores were recorded on the day before operation and follow-up at 3 and 7 d postoperatively. Record the patient's operation to discharge time, postoperative complications.Results: The concentration of cortisol in BIS-I group was higher than that in BIS-II group. There was no significant difference in extubation time, extubation VAS score and MMSE score after operation.Conclusion:There were no significant differences in the BIS values between 45 and 65 for the elderly patients undergoing upper abdominal surgery, and there were no significant differences in the patients' postoperative stress, wake, extubation, early postoperative pain scores and postoperative cognitive function. BIS values in 45-55 compared to 55-65 patients with low plasma cortisol levels may be associated with better control of stress levels, to maintain the BIS value between 45-55 anesthesia depths is more reasonable. 展开更多
关键词 Old age Total intravenous ANESTHESIA ANESTHESIA DEPTH MMSE SCORE Bispectral index Plasma CORTISOL
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Lipopolysaccharide-induced Trigeminal Ganglion Nerve Fiber Damage is Associated with Autophagy Inhibition
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作者 Yong LI jing LI +1 位作者 Sheng-sheng WEI jing du 《Current Medical Science》 SCIE CAS 2023年第3期489-495,共7页
Objective This study aimed to determine whether lipopolysaccharide(LPS)induces the loss of corneal nerve fibers in cultured trigeminal ganglion(TG)cells,and the underlying mechanism of LPS-induced TG neurite damage.Me... Objective This study aimed to determine whether lipopolysaccharide(LPS)induces the loss of corneal nerve fibers in cultured trigeminal ganglion(TG)cells,and the underlying mechanism of LPS-induced TG neurite damage.Methods TG neurons were isolated from C57BL/6 mice,and the cell viability and purity were maintained for up to 7 days.Then,they were treated with LPS(1µg/mL)or the autophagy regulator(autophibib and rapamycin)alone or in combination for 48 h,and the length of neurites in TG cells was examined by the immunofluorescence staining of the neuron-specific proteinβ3-tubulin.Afterwards,the molecular mechanisms by which LPS induces TG neuron damage were explored.Results The immunofluorescence staining revealed that the average length of neurites in TG cells significantly decreased after LPS treatment.Importantly,LPS induced the impairment of autophagic flux in TG cells,which was evidenced by the increase in the accumulation of LC3 and p62 proteins.The pharmacological inhibition of autophagy by autophinib dramatically reduced the length of TG neurites.However,the rapamycin-induced activation of autophagy significantly lessened the effect of LPS on the degeneration of TG neurites.Conclusion LPS-induced autophagy inhibition contributes to the loss of TG neurites. 展开更多
关键词 LIPOPOLYSACCHARIDE AUTOPHAGY trigeminal ganglion neurons
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Nuclear receptors modulate inflammasomes in the pathophysiology and treatment of major depressive disorder
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作者 Han Wang Wei-jing Kan +8 位作者 Yuan Feng Lei Feng Yang Yang Pei Chen jing-Jie Xu Tian-Mei Si Ling Zhang Gang Wang jing du 《World Journal of Psychiatry》 SCIE 2021年第12期1191-1205,共15页
Major depressive disorder(MDD)is highly prevalent and is a significant cause of mortality and morbidity worldwide.Currently,conventional pharmacological treatments for MDD produce temporary remission in<50%of patie... Major depressive disorder(MDD)is highly prevalent and is a significant cause of mortality and morbidity worldwide.Currently,conventional pharmacological treatments for MDD produce temporary remission in<50%of patients;therefore,there is an urgent need for a wider spectrum of novel antidepressants to target newly discovered underlying disease mechanisms.Accumulated evidence has shown that immune inflammation,particularly inflammasome activity,plays an important role in the pathophysiology of MDD.In this review,we summarize the evidence on nuclear receptors(NRs),such as glucocorticoid receptor,mineralocorticoid receptor,estrogen receptor,aryl hydrocarbon receptor,and peroxisome proliferator-activated receptor,in modulating the inflammasome activity and depression-associated behaviors.This review provides evidence from an endocrine perspective to understand the role of activated NRs in the pathophysiology of MDD,and to provide insight for the discovery of antidepressants with novel mechanisms for this devastating disorder. 展开更多
关键词 Major depressive disorder Immune inflammation INFLAMMASOME Nuclear receptors
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Characteristics of corneal aberration in patients with bilateral keratoconus and unilateral corneal Vogt’s striae
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作者 Sheng-Sheng Wei Yong Li +4 位作者 Zhi-Qing Wu Jian-Guo Liu jing du jing Li Yao-Hua Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2316-2320,共5页
AIM:To assess the corneal high-order aberration(HOA)and its correlation with corneal morphological parameters in patients with bilateral keratoconus(KCN)and unilateral Vogt’s striae.METHODS:A total of 168 eyes of 84 ... AIM:To assess the corneal high-order aberration(HOA)and its correlation with corneal morphological parameters in patients with bilateral keratoconus(KCN)and unilateral Vogt’s striae.METHODS:A total of 168 eyes of 84 patients with KCN,whose corneas had definite signs of unilateral Vogt’s striae,were enrolled.Corneal HOA and morphological parameters were measured using Pentacam HR.RESULTS:The corneal morphological parameters between KCN eyes with and without Vogt’s striae were evidently different(P<0.001).The 3rd coma 90°,4th spherical aberration,5th coma 90°,root-mean-square(RMS)(total),and RMS(HOA)in the front,back surfaces and total cornea in KCN eyes with Vogt’s striae were significantly higher than those in KCN eyes without Vogt’s striae(P<0.001).In KCN eyes with Vogt’s striae,the 3rd coma 90°and 4th spherical aberration in the front surface and total cornea were negatively correlated with flat keratometry value(K1),steep keratometry value(K2),mean keratometry value(Km),maximum keratometry value(Kmax),anterior corneal elevation(ACE),and posterior corneal elevation(PCE;P<0.05).The 3rd coma 90°,4th spherical aberration in back surface and RMS(total),RMS(HOA)in the front,back surfaces,total cornea were positively correlated with K1,K2,Km,Kmax,ACE,and PCE(P<0.05).CONCLUSION:Corneal HOA especially vertical coma and spherical aberration may increase when Vogt’s striae appeared in KCN eyes.The scale of increase is significantly related with changes in corneal shapes. 展开更多
关键词 KERATOCONUS CORNEA corneal aberration corneal morphological Vogt’s striae
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内镜黏膜下剥离术治疗消化道早期癌及癌前病变长期疗效的单中心回顾性队列分析 被引量:37
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作者 杜静 韩勇 +2 位作者 吴伟权 李鹏 杨建民 《中国内镜杂志》 北大核心 2017年第8期13-17,共5页
目的研究内镜黏膜下剥离术(ESD)治疗消化道早癌或癌前病变的长期疗效以及术后复发的影响因素。方法收集73例患者的临床及随访资料。采用Kaplan-Meier法,Log-rank和Breslow检验,以及Cox风险比例模型进行统计学分析。结果胃和结直肠ESD术... 目的研究内镜黏膜下剥离术(ESD)治疗消化道早癌或癌前病变的长期疗效以及术后复发的影响因素。方法收集73例患者的临床及随访资料。采用Kaplan-Meier法,Log-rank和Breslow检验,以及Cox风险比例模型进行统计学分析。结果胃和结直肠ESD术后中位无复发生存时间(DFS)大于该研究最长随访时间(65个月),食管中位生存时间为44.5个月;与胃和结直肠相比,食管ESD术后DFS明显减少(χ~2=12.61,P=0.000;χ~2=7.09,P=0.008);病灶异型程度(浸润深度)和病灶面积影响ESD术后DFS(P=0.027,OR=2.38,95%CI:1.10~5.12;P=0.074,OR=0.90,95%CI:0.80~1.01)。结论 ESD术是切除消化道早期癌和癌前病变并维持长期不复发的有效内镜下手术方法 ;异型程度(浸润深度)是影响ESD术后DFS的独立危险因素;病灶面积在影响ESD术后的DFS方面具有临床意义。 展开更多
关键词 内镜黏膜下剥离术 早期癌 癌前病变 消化道
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维持性血液透析患者血清骨硬化蛋白与颈动脉内膜中层厚度的关系 被引量:1
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作者 赵战云 尹丽丽 +4 位作者 杜静 周艳萍 孟祥艳 宋机光 袁翠萍 《中国现代医学杂志》 CAS 2019年第19期72-76,共5页
目的了解维持性血液透析患者骨硬化蛋白水平与动脉硬化间的关系。方法收集75例维持性血液透析患者每周第1次血液透析前的血液标本,检测血清全段甲状旁腺激素(iPTH)、骨硬化蛋白水平,同时B超测定颈动脉内膜中层厚度(IMT),所有患者以血清... 目的了解维持性血液透析患者骨硬化蛋白水平与动脉硬化间的关系。方法收集75例维持性血液透析患者每周第1次血液透析前的血液标本,检测血清全段甲状旁腺激素(iPTH)、骨硬化蛋白水平,同时B超测定颈动脉内膜中层厚度(IMT),所有患者以血清骨硬化蛋白平均值152.34 pmol/L为界,分为低骨硬化蛋白组及高骨硬化蛋白组,比较两组患者颈动脉IMT及相关指标,对颈动脉IMT与骨硬化蛋白水平及相关因素间进行相关性分析、回归分析。结果与高骨硬化蛋白组比较,低骨硬化蛋白组患者颈动脉IMT、血清iPTH及碱性磷酸酶(ALP)水平均升高(P <0.05),颈动脉IMT与骨硬化蛋白呈负相关(r=-0.738,P=0.000),与iPTH呈正相关(r=0.382,P=0.001)。骨硬化蛋白与iPTH及ALP水平呈负相关(r=-0.420和-0.285,P=0.000和0.013)。Logistic回归分析显示,血清骨硬化蛋白水平是颈动脉IMT的影响因素[O^R=0.92,(95%CI:0.88,0.97)]。结论在维持性血液透析患者中,颈动脉IMT与血清骨硬化蛋白水平呈负相关,较低的骨硬化蛋白水平提示患者动脉硬化较重。 展开更多
关键词 颈动脉内膜中层厚度 骨硬化蛋白 动脉硬化
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利用空间位阻和氢溢流协同作用促进5-羟甲基糠醛选择性加氢制备5-甲基糠醛 被引量:2
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作者 李少鹏 杜靖 +10 位作者 张彬 刘艳贞 梅清清 孟庆磊 董明华 杜鹃 赵志娟 郑黎荣 韩布兴 赵美廷 刘会贞 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第10期65-72,共8页
化学工业生产中,用氢气为还原剂,通过选择性加氢可以制备多种重要化学品。5-羟甲基糠醛是重要的生物质基平台化合物,而5-甲基糠醛是用途广泛的化学品。由5-羟甲基糠醛加氢得到5-甲基糠醛是一条非常理想的路径,但是选择性活化C―OH非常... 化学工业生产中,用氢气为还原剂,通过选择性加氢可以制备多种重要化学品。5-羟甲基糠醛是重要的生物质基平台化合物,而5-甲基糠醛是用途广泛的化学品。由5-羟甲基糠醛加氢得到5-甲基糠醛是一条非常理想的路径,但是选择性活化C―OH非常困难。本文设计并制备了Pt@PVP/Nb_(2)O_(5)(PVP:聚乙烯吡咯烷酮)催化剂,该催化体系巧妙地结合了位阻效应、氢溢流和催化剂界面的电子效应,系统研究了该催化剂对5-羟甲基糠醛选择性加氢制备5-甲基糠醛催化性能,在最优条件下,5-甲基糠醛的选择性可达92%。利用密度泛函理论计算研究了5-羟甲基糠醛选择性加氢制备5-甲基糠醛反应路径。 展开更多
关键词 生物质 5-羟甲基糠醛 选择性加氢脱氧反应 空间位阻 氢溢流
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化学化工虚拟仿真实验教学平台的建设与应用 被引量:28
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作者 杜静 赵温涛 +1 位作者 冯霞 马骁飞 《大学化学》 CAS 2021年第1期144-150,共7页
虚拟仿真教学是近年来一种新型教学模式,是一种融合多学科、多区域、多层次的实验教学方法,以天津大学化学化工虚拟仿真实验平台建设为例,介绍化学化工安全知识、理论知识、实验内容的有机融合,虚拟仿真资源的具体内容及虚拟仿真实验平... 虚拟仿真教学是近年来一种新型教学模式,是一种融合多学科、多区域、多层次的实验教学方法,以天津大学化学化工虚拟仿真实验平台建设为例,介绍化学化工安全知识、理论知识、实验内容的有机融合,虚拟仿真资源的具体内容及虚拟仿真实验平台的特色。提供了一种虚拟仿真资源与传统教学资源高效结合的新模式,推动了化学化工类实验教学的发展。 展开更多
关键词 实验教学平台 虚拟仿真 有机融合
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加压氢化反应虚拟仿真实验的建设与应用 被引量:7
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作者 杜静 马骁飞 赵温涛 《大学化学》 CAS 2021年第2期91-101,共11页
为扩大加压氢化这一实用技术在本科教学中的应用,使学生能够熟练使用氢气这种易燃易爆气体,提出并建设了加压氢化反应的虚拟仿真实验。基于三位诺贝尔奖获得者在氢化反应领域的相关工作,开展加压氢化反应的虚拟仿真实验。该实验建设包... 为扩大加压氢化这一实用技术在本科教学中的应用,使学生能够熟练使用氢气这种易燃易爆气体,提出并建设了加压氢化反应的虚拟仿真实验。基于三位诺贝尔奖获得者在氢化反应领域的相关工作,开展加压氢化反应的虚拟仿真实验。该实验建设包括仿真软件资源、学习共享平台、移动端学习资源、流程建设、评价体系建设,充分发挥虚拟仿真技术在化学化工领域中的作用,为一些难以在教学中开展的化学化工实验课程开辟了新的道路。 展开更多
关键词 虚拟仿真 加压氢化 化学化工
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跨上皮角膜胶原交联手术治疗进展期圆锥角膜的疗效 被引量:5
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作者 魏升升 李勇 +5 位作者 刘建国 张耀花 蔡艳 杜婧 万雅群 李晶 《国际眼科杂志》 CAS 北大核心 2021年第4期675-679,共5页
目的:分析跨上皮角膜胶原交联手术治疗进展期圆锥角膜后1a的疗效并讨论其临床意义。方法:收集2017-01/2018-12于我院进行快速跨上皮角膜胶原交联手术的进展期圆锥角膜患者45例48眼,术后随访1a,分析手术前后视力、角膜最薄点厚度、角膜... 目的:分析跨上皮角膜胶原交联手术治疗进展期圆锥角膜后1a的疗效并讨论其临床意义。方法:收集2017-01/2018-12于我院进行快速跨上皮角膜胶原交联手术的进展期圆锥角膜患者45例48眼,术后随访1a,分析手术前后视力、角膜最薄点厚度、角膜内皮细胞计数、角膜交联线深度、角膜前表面曲率Km值及角膜生物力学参数等变化情况。结果:与术前比较,本组患者术后裸眼视力明显改善(P<0.05),但最佳矫正视力、角膜最薄点厚度和角膜内皮细胞计数均无明显变化(P>0.05),术后6mo,1a角膜前表面曲率Km值(48.54±2.57、48.77±2.29D)均显著下降,角膜生物力学参数第1次压平宽度(1.52±0.21、1.57±0.22mm)均显著降低(P<0.05),第2次压平速度绝对值(0.82±0.09、0.82±0.18m/s)均显著增加(P<0.05)。结论:快速跨上皮角膜胶原交联手术治疗进展期圆锥角膜对裸眼视力有明显改善,术后角膜生物力学也有改善,但最佳矫正视力改善不明显。 展开更多
关键词 圆锥角膜 胶原交联手术 裸眼视力 最佳矫正视力 角膜生物力学
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An Accurate and Extensible Machine Learning Classifier for Flow-Level Traffic Classification 被引量:2
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作者 Gang Lu Ronghua Guo +1 位作者 Ying Zhou jing du 《China Communications》 SCIE CSCD 2018年第6期125-138,共14页
Machine Learning(ML) techniques have been widely applied in recent traffic classification.However, the problems of both discriminator bias and class imbalance decrease the accuracies of ML based traffic classifier. In... Machine Learning(ML) techniques have been widely applied in recent traffic classification.However, the problems of both discriminator bias and class imbalance decrease the accuracies of ML based traffic classifier. In this paper, we propose an accurate and extensible traffic classifier. Specifically, to address the discriminator bias issue, our classifier is built by making an optimal cascade of binary sub-classifiers, where each binary sub-classifier is trained independently with the discriminators used for identifying application specific traffic. Moreover, to balance a training dataset,we apply SMOTE algorithm in generating artificial training samples for minority classes.We evaluate our classifier on two datasets collected from different network border routers.Compared with the previous multi-class traffic classifiers built in one-time training process,our classifier achieves much higher F-Measure and AUC for each application. 展开更多
关键词 traffic classification class imbalance dircriminator bias encrypted traffic machine learning
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Prevalence of Metabolic Syndrome and Risk Factors Among Chinese Adults:Results from a Population-Based Study—Beijing,China,2017–2018 被引量:5
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作者 Jufen Liu Qingping Liu +13 位作者 Zhiwen Li jing du Chao Wang Yanlin Gao Zaihua Wei jing Wang Yunping Shi Jianting Su Yang Liu Ping Wang Chunyan Xie Gang Li Bing Shao Le Zhang 《China CDC weekly》 2022年第29期640-645,共6页
Summary What is already known about this topic?Metabolic syndrome(MetS)is one of the most easily available health indicative markers for cardiovascular diseases,and it has become a major public health problem worldwid... Summary What is already known about this topic?Metabolic syndrome(MetS)is one of the most easily available health indicative markers for cardiovascular diseases,and it has become a major public health problem worldwide due to increasing urbanization and aging populations.The prevalence of MetS increased dramatically in China,however,there are no records of MetS defined by the 2017 Chinese Diabetes Society for Beijing by far.What is added by this report?In this study,the data of 24,412 participants aged 18–74 years from a large population-based study in Beijing was collected.The overall prevalence of MetS among Beijing residents was 24.5%.The prevalence was 35.2%in males and 15.4%in females.What are the implications for public health practice?Effective public health strategies should target males,people with older age,lower education,higher body mass index,smokers,those who drink alcohol,those who are unemployed or retired,and those who live in rural areas on MetS prevention and control. 展开更多
关键词 METABOLIC PREVENTION SMOKE
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Microfluidic chips for the endothelial biomechanics and mechanobiology of the vascular system 被引量:2
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作者 HAORAN SU KEXIN LI +4 位作者 XIAO LIU jing du LI WANG XIAOYAN DENG YUBO FAN 《BIOCELL》 SCIE 2021年第4期797-811,共15页
Endothelial cells arranged on the vessel lumen are constantly stimulated by blood flow,blood pressure and pressureinduced cyclic stretch.These stimuli are sensed through mechanical sensory structures and converted int... Endothelial cells arranged on the vessel lumen are constantly stimulated by blood flow,blood pressure and pressureinduced cyclic stretch.These stimuli are sensed through mechanical sensory structures and converted into a series of functional responses through mechanotransduction pathways.The process will eventually affect vascular health.Therefore,there has been an urgent need to establish in vitro endothelial biomechanics and mechanobiology of models,which reproduce three-dimensional structure vascular system.In recent years,the rapid development in microfluidic technology makes it possible to replicate the key structural and functionally biomechanical characteristics of vessels.Here,we summarized the progress of microfluidic chips used for the investigation of endothelial biomechanics and mechanobiology of the vascular system.Firstly,we elucidated the contribution of shear stress and circumferential stress,to vascular physiology.Then,we reviewed some applications using microfluidic technology in angiogenesis and vasculogenesis,endothelial permeability and mechanotransduction,as well as the blood-brain barrier under these physical forces.Finally,we discussed the future obstacles in terms of the development and application of microfluidic vascular chips. 展开更多
关键词 Endothelial cells Vascular system MECHANOTRANSDUCTION Microfluidic chip
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