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Cancer risk stratification system and classification of gastritis:Perspectives
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作者 Sergey M Kotelevets Sergey A Chekh Sergey Z Chukov 《World Journal of Meta-Analysis》 2023年第1期18-28,共11页
Kyoto global consensus reports that the current ICD-10 classification for gastritis is obsolete.The Kyoto classification of gastritis states that severe mucosal atrophy has a high risk of gastric cancer,while mild to ... Kyoto global consensus reports that the current ICD-10 classification for gastritis is obsolete.The Kyoto classification of gastritis states that severe mucosal atrophy has a high risk of gastric cancer,while mild to moderate atrophy has a low risk.The updated Kimura-Takemoto classification of atrophic gastritis considers five histological types of multifocal corpus atrophic gastritis according to stages C2 to O3.This method of morphological diagnosis of atrophic gastritis increases sensitivity by 2.4 times for severe atrophy compared to the updated Sydney system.This advantage should be considered when stratifying the high risk of gastric cancer.The updated Kimura-Takemoto classification of atrophic gastritis should be used as a reference standard(gold standard)in studies of morphofunctional relationships to identify serological markers of atrophic gastritis with evidence-based effectiveness.The use of artificial intelligence in the serological screening of atrophic gastritis makes it possible to screen a large number of the population.During serological screening of atrophic gastritis and risk stratification of gastric cancer,it is advisable to use the Kyoto classification of gastritis with updated Kimura-Takemoto classification of atrophic gastritis. 展开更多
关键词 Atrophic gastritis Cancer risk stratification Gastric cancer prevention Classification of gastritis
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Set up and validation of Chinese Risk Stratification System for Coronary Artery Bypass Grafting
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作者 中国心血管外科注册登记研究协作组 《外科研究与新技术》 2011年第3期180-181,共2页
Objective Our study aims to evaluate the performance of Chinese risk stratification system for coronary artery bypass grafting (CABG) in the prediction of in-hospital mortality and major postoperative complications af... Objective Our study aims to evaluate the performance of Chinese risk stratification system for coronary artery bypass grafting (CABG) in the prediction of in-hospital mortality and major postoperative complications afterCABG. Methods Clinical information of 9564 consecutive CABG patients was collected in Chinese Coronary Artery Bypass Grafting Registry which recruited 43 centers over China between 2007 and 2008. 展开更多
关键词 CABG AUC Set up and validation of Chinese Risk stratification system for Coronary Artery Bypass Grafting
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Performance of risk stratification systems for gastrointestinal stromal tumors: A multicenter study 被引量:2
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作者 Tao Chen Liang-Ying Ye +11 位作者 Xing-Yu Feng Hai-Bo Qiu Peng Zhang Yi-Xin Luo Li-Yi Yuan Xin-Hua Chen Yan-Feng Hu Hao Liu Yong Li Kai-Xiong Tao Jiang Yu Guo-Xin Li 《World Journal of Gastroenterology》 SCIE CAS 2019年第10期1238-1247,共10页
BACKGROUND Gastrointestinal stromal tumors(GISTs) are the most common mesenchymal tumor type in the gastrointestinal system. Presently, various classification systems to prognosticate GISTs have been proposed.AIM To e... BACKGROUND Gastrointestinal stromal tumors(GISTs) are the most common mesenchymal tumor type in the gastrointestinal system. Presently, various classification systems to prognosticate GISTs have been proposed.AIM To evaluate the application value of four different risk stratification systems for GISTs.METHODS Patients who were diagnosed with GISTs and underwent surgical resection at four hospitals from 1998 to 2015 were identified from a database. Risk of recurrence was stratified by the modified National Institute of Health(NIH)criteria, the Armed Forces Institute of Pathology(AFIP) criteria, the Memorial Sloan Kettering Cancer Center(MSKCC) prognostic nomogram, and the contour maps. Receiver operating characteristic(ROC) curves were established to compare the four abovementioned risk stratification systems based on the area under the curve(AUC).RESULTS A total of 1303 patients were included in the study. The mean age of the patients was 55.77 ± 13.70 yr; 52.3% of the patients were male. The mean follow-up period was 64.91 ± 35.79 mo. Approximately 67.0% the tumors were located in the stomach, and 59.5% were smaller than 5 cm; 67.3% of the patients had a mitotic count ≤ 5/50 high-power fields(HPFs). Thirty-four tumors ruptured before and during surgery. Univariate analysis demonstrated that tumor size > 5 cm(P <0.05), mitotic count > 5/50 HPFs(P < 0.05), non-gastric location(P < 0.05), and tumor rupture(P < 0.05) were significantly associated with increased recurrence rates. According to the ROC curve, the AFIP criteria showed the largest AUC(0.754).CONCLUSION According to our data, the AFIP criteria were associated with a larger AUC than the NIH modified criteria, the MSKCC nomogram, and the contour maps, which might indicate that the AFIP criteria have better accuracy to support therapeutic decision-making for patients with GISTs. 展开更多
关键词 GASTROINTESTINAL STROMAL TUMORS Risk stratification Prognosis Modified National Institute of Health CRITERIA Armed Forces Institute of Pathology CRITERIA MEMORIAL Sloan Kettering Cancer Center prognostic nomogram Contour maps GASTROINTESTINAL TUMORS
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Discussion on the extended form of internal solitary wave models between two typical stratification systems
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作者 Jiu-ming Zhang Li Zou +2 位作者 Tie-zhi Sun Zong-bing Yu Hao Wang 《Journal of Hydrodynamics》 SCIE EI CSCD 2023年第1期155-170,共16页
The two-layer fluid system and the continuous density system are based on two typical simplified stratification conditions to support the propagation of the internal solitary waves(ISWs).The aim of this study is to es... The two-layer fluid system and the continuous density system are based on two typical simplified stratification conditions to support the propagation of the internal solitary waves(ISWs).The aim of this study is to establish several extension methods of the classical ISW models across the stratification systems in an attempt to find a simple ISW structure that can propagate more stably,and to determine whether the stable ISW structure in the two typical stratification systems can be expressed in terms of a consistent nonlinear model.For the constructed ISW structures,the propagation stability has been investigated by taking the Euler equations as the evolution equations.The results show that the ISW structure constructed from the Miyata-Choi-Camassa(MCC)model undergoes two stages of instability and the re-stable ISW has a larger available potential energy and a smaller kinetic energy than the initialized condition.This illustrates the limitation of the weakly dispersive assumption in the MCC model.In contrast,the ISW structure constructed from the Dubreil-Jacotin-Long(DJL)model for the two-layer fluid system is generally stable,due to the fact that the Boussinesq approximation introduced in the derivation of the DJL model will be automatically satisfied in this system.The initial condition interpolated from the DJL model with a thin pycnocline thickness can be regarded as an appropriate ISW structure for the two-layer system and is even more stable than that initialized by the MCC model.In addition,the effect of the Boussinesq approximation is also included in the discussion.The approximation can be considered equivalent to a weakly dispersive assumption and should not be ignored for the ISW problem in the continuous density system. 展开更多
关键词 Internal solitary wave stratification condition the Miyata-Choi-Camassa(MCC)model the Dubreil-Jacotin-Long(DJL)equation Boussinesq approximation
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New scoring system for acute chest pain risk stratification: Is it worth SVEAT-ing it?
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作者 Mahati Dasari Pramukh Arun Kumar +1 位作者 Yuvaraj Singh Eddison Ramsaran 《World Journal of Cardiology》 2023年第4期200-204,共5页
The emergency room is a very potent environment in the hospital.With the growing demands of the population,improved accessibility to health resources,and the onslaught of the triple pandemic,it is extremely crucial to... The emergency room is a very potent environment in the hospital.With the growing demands of the population,improved accessibility to health resources,and the onslaught of the triple pandemic,it is extremely crucial to triage patients at presentation.In the spectrum of complaints,chest pain is the commonest.Despite it being a daily ailment,chest pain brings concern to every physician at first.Chest pain could span from acute coronary syndrome,pulmonary embolism,and aortic dissection(all potentially fatal)to reflux,zoster,or musculoskeletal causes that do not need rapid interventions.We often employ scoring systems such as GRACE/PURSUIT/TIMI to assist in clinical decision-making.Over the years,the HEART score became a popular and effective tool for predicting the risk of 30-d major adverse cardiovascular events.Recently,a new scoring system called SVEAT was developed and compared to the HEART score.We have attempted to summarize how these scoring systems differ and their generalizability.With an increasing number of scoring systems being introduced,one must also prevent anchorage bias;i.e.,tools such as these are only diagnosis-specific and not organ-specific,and other emergent differential diagnoses must also be kept in mind before discharging the patient home without additional workup. 展开更多
关键词 Chest pain Acute coronary syndrome SVEAT score HEART score TIMI score Risk stratification scores
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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect
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作者 CHENG Yun SONG Zhanping +2 位作者 XU Zhiwei YANG Tengtian TIAN Xiaoxu 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1058-1074,共17页
The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and tempora... The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass. 展开更多
关键词 Hard siltstone Failure mechanism stratification effect Infrared radiation characteristic Temporal-damage mechanism DISSIMILATION
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Stability of the Stratification of Water Bodies in the North Passage of the Yangtze River Estuary Based on the EFDC Model
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作者 WU De’an LI Xin WANG Yigang 《Journal of Ocean University of China》 CAS CSCD 2024年第1期23-32,共10页
To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC res... To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides. 展开更多
关键词 Yangtze Estuary North Passage EFDC model stratification stability salinity distribution
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Risk stratification system for skin and soft tissue infections after allogeneic hematopoietic stem cell transplantation:PAH risk score
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作者 Shan Chong Yun He +16 位作者 Yejun Wu Peng Zhao Xiaolu Zhu Fengrong Wang Yuanyuan Zhang Xiaodong Mo Wei Han Jingzhi Wang Yu Wang Huan Chen Yuhong Chen Xiangyu Zhao Yingjun Chang Lanping Xu Kaiyan Liu Xiaojun Huang Xiaohui Zhang 《Frontiers of Medicine》 SCIE CSCD 2022年第6期957-968,共12页
Skin and soft tissue infections(SSTIs)refer to infections involving the skin,subcutaneous tissue,fascia,and muscle.In transplant populations with hematological malignancies,an immunocompromised status and the routine ... Skin and soft tissue infections(SSTIs)refer to infections involving the skin,subcutaneous tissue,fascia,and muscle.In transplant populations with hematological malignancies,an immunocompromised status and the routine use of immunosuppressants increase the risk of SSTIs greatly.However,to date,the profiles and clinical outcomes of SSTIs in hematopoietic stem cell transplantation(HSCT)patients remain unclear.This study included 228 patients(3.67%)who developed SSTIs within 180 days after allogeneic HSCT from January 2004 to December 2019 in Peking University People’s Hospital.The overall annual survival rate was 71.5%.We compared the differences between survivors and non-survivors a year after transplant and found that primary platelet graft failure(PPGF),comorbidities of acute kidney injury(AKI),and hospital-acquired pneumonia(HAP)were independent risk factors for death in the study population.A PPGF-AKI-HAP risk stratification system was established with a mortality risk score of 1×PPGF+1×AKI+1×HAP.The areas under the curves of internal and external validation were 0.833(95%CI 0.760–0.906)and 0.826(95%CI 0.715–0.937),respectively.The calibration plot revealed the high consistency of the estimated risks,and decision curve analysis showed considerable net benefits for patients. 展开更多
关键词 skin and soft tissue infections hematopoietic stem cell transplantation risk stratification system MORTALITY
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Thermal stratification level of low sidewall air supply with air-conditioning system in large space 被引量:3
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作者 黄晨 蔡宁 高雪垒 《Journal of Central South University》 SCIE EI CAS 2009年第S1期166-170,共5页
The thermal stratification level of low sidewall air supply system in large space was defined. Depending on the experiment of low sidewall air supply in summer 2008,the thermal stratification level was studied by simu... The thermal stratification level of low sidewall air supply system in large space was defined. Depending on the experiment of low sidewall air supply in summer 2008,the thermal stratification level was studied by simulation. Based on the simulation of experiment condition,the air velocity and vertical temperature distribution in a large space were simulated at different air-outlet velocities,and then the thermal stratification level line was obtained. The simulation results well match with the experimental ones and the average relative error is 3.4%. The thermal stratification level is heightened by increasing the air-outlet velocity with low sidewall air supply mode. It is concluded that when air-outlet velocity is 0.29 m/s,which is the experimental case,a uniform thermal environment in the higher occupied zone and a stable stratification level are formed. When the air-outlet velocity is low,such as 0.05 m/s,the thermal stratification level is too low and the air velocity is too small to meet the human thermal comfort in the occupied zone. So,it would be reasonable that the air-outlet velocity may be designed as 0.31 m/s if the height of the occupied zone is 2 m. 展开更多
关键词 large space low SIDEWALL AIR supply thermal stratification LEVEL numerical simulation air-outlet VELOCITY
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Experimental Study on Indoor Thermal Stratification in Large Space by under Floor Air Distribution System (UFAD) in Summer 被引量:1
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作者 Xin Wang Chen Huang +2 位作者 Weiwu Cao Xuelei Gao Wen Liu 《Engineering(科研)》 2011年第4期384-388,共5页
A ventilation method of down-supply up-return has grown popular in large space in recent years for comfort ventilation with low thermal load, especially in China, including gymnasium, factory space, and exhibition hal... A ventilation method of down-supply up-return has grown popular in large space in recent years for comfort ventilation with low thermal load, especially in China, including gymnasium, factory space, and exhibition hall, etc. The undisturbed flow pattern in the space gives a gradient in temperature, and the vertical thermal stratification appears markedly in large space. The object for this paper is to understand the behaviour of an under floor air distribution system in a ventilated space. The thermal stratification characteristics in a real UFAD experimental space were measured. The effects of different supply conditions on the thermal stratification characteristics are investigated based on the experimental results. The relations between space air stratification and the control parameter is predicted. It can be indicated that there are 4 zones composing the vertical thermal stratification. And different zone has different control parameter. 展开更多
关键词 UFAD system Thermal stratification Temperature GRADIENT LARGE Space Control PARAMETER
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Comparison of multiple salinity datasets:upper ocean salinity and stratification in the tropical Pacific during the Argo period
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作者 Meng DONG Hai ZHI +1 位作者 Yu HUANG Shiwei SHI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1660-1677,共18页
Ocean salinity is an important variable that affects the ocean stratification.We compared the salinity and ocean stratification in the tropical Pacific derived from the Argo(Array for Real-time Geostrophic Oceanograph... Ocean salinity is an important variable that affects the ocean stratification.We compared the salinity and ocean stratification in the tropical Pacific derived from the Argo(Array for Real-time Geostrophic Oceanography data),EN4(Ensemble 4 analysis),SODA(the Simple Ocean Data Assimilation reanalysis),IAP(Institute of Atmospheric Physics data),and ORAS4(Ocean Reanalysis System 4)over 2005–2017.Results show that the spatial distribution of climatological mean of sea surface salinity(SSS)in all the products is consistent,and the low salinity region showed large deviation and strong dispersion.The Argo has the smallest RMSE and the highest correlation with the ensemble mean,while the IAP shows a high-salinity deviations relative to other datasets.All the products show high positive correlations between the sea surface density(SSD)and SSS with respect to the deviations of climatological mean from ensemble mean,suggesting that the SSD deviation may be mainly influenced by the SSS deviation.In the aspect of the ocean stratification,the mixed layer depth(MLD)climatological mean in the Argo shows the highest correlation with the ensemble mean,followed by EN4,IAP,ORAS4,and SODA.The Argo and EN4 show thicker barrier layer(BL)relative to the ensemble mean while the SODA displays the largest negative deviation in the tropical western Pacific.Furthermore,the EN4,ORAS4,and IAP underestimate the stability in the upper ocean at the depths of 20–140 m,while Argo overestimates ocean stability.The salinity fronts in the western-central equatorial Pacific from Argo,EN4,and ORAS4 are consistent,while those from SODA and IAP show large deviations with a westward position in amplitude of 0°–6°and 0°–10°,respectively.The SSS trend patterns from all the products are consistent in having ensemble mean with high spatial correlations of 0.95–0.97. 展开更多
关键词 SALINITY ocean stratification upper ocean tropical Pacific data products
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Ground Penetrating Radar (GPR) Identification Method for Agricultural Soil Stratification in a Typical Mollisols Area of Northeast China
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作者 RUAN Weimin LIU Baojiang +2 位作者 LIU Huanjun DONG Hang SUI Yueyu 《Chinese Geographical Science》 SCIE CSCD 2023年第4期664-678,共15页
In order to achieve a rapid and accurate identification of soil stratification information and accelerate the development of smart agriculture,this paper conducted soil stratification experiments on agricultural soils... In order to achieve a rapid and accurate identification of soil stratification information and accelerate the development of smart agriculture,this paper conducted soil stratification experiments on agricultural soils in the Mollisols area of Northeast China using Ground Penetrating Radar(GPR)and obtained different types of soil with frequencies of 500 MHz,250 MHz,and 100 MHz antennas.The soil profile data were obtained for 500 MHz,250 MHz,and 100 MHz antennas,and the dielectric properties of each type of soil were analyzed.In the image processing procedure,wavelet analysis was first used to decompose the pre-processed radar signal and reconstruct the high-frequency information to obtain the reconstructed signal containing the stratification information.Secondly,the reconstructed signal is taken as an envelope to enhance the stratification information.The Hilbert transform is applied to the envelope signal to find the time-domain variation of the instantaneous frequency and determine the time-domain location of the stratification.Finally,the dielectric constant of each soil horizon is used to obtain the propagation velocity of the electromagnetic wave at the corresponding position to obtain the stratification position of each soil horizon.The research results show that the 500 MHz radar antenna can accurately delineate Ap/Ah,horizon and the absolute accuracy of the stratification is within 5 cm.The effect on the soil stratification below the tillage horizon is not apparent,and the absolute accuracy of the 250 MHz and 100 MHz radar antennas on the stratification is within 9 cm.The overwhelming majority of the overall calculation errors are kept to within 15%.Based on the three central frequency antennas,the soil horizon detection rate reaches 93.3%,which can achieve accurate stratification of soil profiles within 1 m.The experimental and image processing methods used are practical and feasible;however,the GPR will show a missed detection for soil horizons with only slight differences in dielectric properties.Overall,this study can quickly and accurately determine the information of each soil stratification,ultimately providing technical support for acquiring soil configuration information and developing smart agriculture. 展开更多
关键词 soil stratification ground-penetrating radar PROFILING wavelet analysis envelope signal Northeast China
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ON THE RIGOROUS MATHEMATICAL DERIVATION FOR THE VISCOUS PRIMITIVE EQUATIONS WITH DENSITY STRATIFICATION
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作者 蒲学科 周文利 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1081-1104,共24页
In this paper, we rigorously derive the governing equations describing the motion of a stable stratified fluid, from the mathematical point of view. In particular, we prove that the scaled Boussinesq equations strongl... In this paper, we rigorously derive the governing equations describing the motion of a stable stratified fluid, from the mathematical point of view. In particular, we prove that the scaled Boussinesq equations strongly converge to the viscous primitive equations with density stratification as the aspect ratio goes to zero, and the rate of convergence is of the same order as the aspect ratio. Moreover, in order to obtain this convergence result, we also establish the global well-posedness of strong solutions to the viscous primitive equations with density stratification. 展开更多
关键词 Boussinesq equations primitive equations density stratification hydrostatic approximation strong convergence
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The effect of adjuvant transarterial chemoembolization for hepatocellular carcinoma after liver resection based on risk stratification
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作者 Jin-Shu Zeng Jian-Xing Zeng +2 位作者 Yao Huang Jing-Feng Liu Jin-Hua Zeng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第5期482-489,共8页
Background:There is currently no standard adjuvant treatment proven to prevent hepatocellular carcinoma(HCC)recurrence.Recent studies suggest that postoperative adjuvant transarterial chemoembolization(PA-TACE)is bene... Background:There is currently no standard adjuvant treatment proven to prevent hepatocellular carcinoma(HCC)recurrence.Recent studies suggest that postoperative adjuvant transarterial chemoembolization(PA-TACE)is beneficial for patients at high risk of tumor recurrence.However,it is difficult to select the patients.The present study aimed to develop an easy-to-use score to identify these patients.Methods:A total of 4530 patients undergoing liver resection were recruited.Independent risk factors were identified by Cox regression model in the training cohort and the Primary liver cancer big data transarterial chemoembolization(PDTE)scoring system was established.Results:The scoring system was composed of ten risk factors including alpha-fetoprotein(AFP),albuminbilirubin(ALBI)grade,operative bleeding loss,resection margin,tumor capsular,satellite nodules,tumor size and number,and microvascular and macrovascular invasion.Using 5 points as risk stratification,the patients with PA-TACE had higher recurrence-free survival(RFS)compared with non-TACE in>5 points group(P<0.001),whereas PA-TACE patients had lower RFS compared with non-TACE in≤5 points group(P=0.013).In the training and validation cohorts,the C-indexes of PDTE scoring system were 0.714[standard errors(SE)=0.010]and 0.716(SE=0.018),respectively.Conclusions:The model is a simple tool to identify PA-TACE for HCC patients after liver resection with a favorable performance.Patients with>5 points may benefit from PA-TACE. 展开更多
关键词 Hepatocellular carcinoma Liver resection Adjuvant transarterial chemoembolization Scoring system Risk stratification
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Vertical Diffusion Coefficient with Stratification Effect for Silty Sediment Suspension Under Waves
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作者 YANG Guang-yao ZHANG Qing-he 《China Ocean Engineering》 SCIE EI CSCD 2023年第2期323-332,共10页
To analyze previous experimental data of suspended sediment concentration for silty sediment with different sediment particle sizes due to waves, a new stratification correction coefficient is presented. The suspended... To analyze previous experimental data of suspended sediment concentration for silty sediment with different sediment particle sizes due to waves, a new stratification correction coefficient is presented. The suspended sediment concentration gradient and sediment particle diameter are selected as parameters. Furthermore, a diffusion coefficient model with a stratification effect over the whole water depth for silty sediment suspension under waves is developed. The comparison between the suspended sediment concentration calculated by the presented model and several groups of experimental data shows that the model can reasonably reflect the vertical distribution of silty sediment suspension.The stratification effect calculated by the present model decreases with an increase in the sediment particle diameter,which indicates that the model can be extended to describe the suspended sediment concentration of fine to medium sand when the near-bottom sediment concentration is not very high. Although the original model needs to be iteratively solved, the approximate method without iteration is recommended for applications when the near bottom sediment concentration is between 10 and 20 kg/m~3 due to the small difference between the non-iterative and iterative solution for near bed layer suspended sediment concentration, which plays a major role in sediment transport. 展开更多
关键词 stratification silty sediment suspension diffusion coefficient WAVE
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Effect of cold stratification on the temperature range for germination of Pinus koraiensis
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作者 Yuan Song Xinghuan Li +2 位作者 Mingyi Zhang Guowei Xia Chao Xiong 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期221-231,共11页
Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests ... Germination at low spring temperatures may offer a competitive advantage for the growth and survival of plant species inhabiting temperate forest ecosystems.Pinus koraiensis is a dominant species in temperate forests of northeastern China.Its seeds exhibit primary morphophysiological dormancy following dispersal in autumn,limiting natural or artificial regeneration:direct seeding and planting seedlings in spring.The aim of this study was to determine the optimum cold stratification temperature that induces germination to increase towards lower temperatures.Seeds from two populations(Changbaishan and Liangshui)were cold stratified at 0,5 and 10℃.Germination to incubation temperatures(10/5,20/10,25/15 and 30/20℃;14/10 h day/night)were determined after 2 and 4 weeks,and 5.5 and6.5 months of cold stratification.After 5.5 months,approximately 68-91%of seeds from both populations germinated at incubation temperatures of 25/15℃and 30/20℃,regardless of cold stratification temperatures.When the cold stratification temperature was reduced to 0℃and the period increased to 6.5 months,germination at 10/5℃significantly improved,reaching 37%and 64%for the Changbaishan and Liangshui populations,respectively.After 6.5 months of cold stratification,there was a significant linear regression between cold stratification temperatures and germination at10/5℃.The range in temperatures allowing for germination gradually expanded to include lower temperatures with decreasing cold stratification temperatures from 10 to 5℃and further to 0℃. 展开更多
关键词 Cold stratification temperatures Pinus koraiensis Seed germination Germination temperature range
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Substrate,Hormone,Winnowing,and Stratification Influence the Seed Germination of Ilex asprella(Hook.et Arn.)Champ.ex Benth
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作者 Yuquan Huang Fan Wei +4 位作者 QingMa Yang Lin Jinpeng Huang Yanxia Zhu Danfeng Tang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第7期2105-2116,共12页
Ilex asprella(Hook.et Arn.)Champ.ex Benth is one of the most important traditional Chinese medicines in southern China.The seeds of Ilex asprella usually have extremely low germination due to their dormancy characteri... Ilex asprella(Hook.et Arn.)Champ.ex Benth is one of the most important traditional Chinese medicines in southern China.The seeds of Ilex asprella usually have extremely low germination due to their dormancy characteristics,which severely impacts the efficiency of seedling raising and increases labor costs.In this study,to improve the seed germination of I.asprella,the effects of germination substrate,hormone,winnowing,and stratification treatments on the seed germination of I.asprella were investigated.The results of the germination matrix showed that the highest germination percentage of 45.2%was achieved under the 20℃/10℃day/night temperature and vermiculite germination medium conditions.The results of hormone treatments revealed that 100–400 mg/L of gibberellin(GA)and 50–100 mg/L of salicylic acid(SA)were found to be effective in releasing the dormancy of I.asprella seeds.Moreover,winnowing could effectively eliminate unsaturated seeds and impurities,thus improving the seed germination of I.asprella.Furthermore,warm temperature(15℃)stratification could expand the temperature range of I.asprella’s seed germination,which was beneficial for seed germination of I.asprella and for seed nursery at room temperature in production practice.The present study obtained a method to break dormancy and increase seed germination in I.asprella,thereby forming a groundwork for improving the efficiency of large-scale planting of I.asprella. 展开更多
关键词 Ilex asprella seed germination SUBSTRATE WINNOWING HORMONE stratification
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Relationship between multi-slice computed tomography features and pathological risk stratification assessment in gastric gastrointestinal stromal tumors
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作者 Tian-Tian Wang Wei-Wei Liu +6 位作者 Xian-Hai Liu Rong-Ji Gao Chun-Yu Zhu Qing Wang Lu-Ping Zhao Xiao-Ming Fan Juan Li 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第6期1073-1085,共13页
BACKGROUND Computed tomography(CT)imaging features are associated with risk stratification of gastric gastrointestinal stromal tumors(GISTs).AIM To determine the multi-slice CT imaging features for predicting risk str... BACKGROUND Computed tomography(CT)imaging features are associated with risk stratification of gastric gastrointestinal stromal tumors(GISTs).AIM To determine the multi-slice CT imaging features for predicting risk stratification in patients with primary gastric GISTs.METHODS The clinicopathological and CT imaging data for 147 patients with histologically confirmed primary gastric GISTs were retrospectively analyzed.All patients had received dynamic contrast-enhanced CT(CECT)followed by surgical resection.According to the modified National Institutes of Health criteria,147 lesions were classified into the low malignant potential group(very low and low risk;101 lesions)and high malignant potential group(medium and high-risk;46 lesions).The association between malignant potential and CT characteristic features(including tumor location,size,growth pattern,contour,ulceration,cystic degeneration or necrosis,calcification within the tumor,lymphadenopathy,enhancement patterns,unenhanced CT and CECT attenuation value,and enhancement degree)was analyzed using univariate analysis.Multivariate logistic regression analysis was performed to identify significant predictors of high malignant potential.The receiver operating curve(ROC)was used to evaluate the predictive value of tumor size and the multinomial logistic regression model for risk classification.RESULTS There were 46 patients with high malignant potential and 101 with low-malignant potential gastric GISTs.Univariate analysis showed no significant differences in age,gender,tumor location,calcification,unenhanced CT and CECT attenuation values,and enhancement degree between the two groups(P>0.05).However,a significant difference was observed in tumor size(3.14±0.94 vs 6.63±3.26 cm,P<0.001)between the low-grade and high-grade groups.The univariate analysis further revealed that CT imaging features,including tumor contours,lesion growth patterns,ulceration,cystic degeneration or necrosis,lymphadenopathy,and contrast enhancement patterns,were associated with risk stratification(P<0.05).According to binary logistic regression analysis,tumor size[P<0.001;odds ratio(OR)=26.448;95%confidence interval(CI):4.854-144.099)],contours(P=0.028;OR=7.750;95%CI:1.253-47.955),and mixed growth pattern(P=0.046;OR=4.740;95%CI:1.029-21.828)were independent predictors for risk stratification of gastric GISTs.ROC curve analysis for the multinomial logistic regression model and tumor size to differentiate high-malignant potential from low-malignant potential GISTs achieved a maximum area under the curve of 0.919(95%CI:0.863-0.975)and 0.940(95%CI:0.893-0.986),respectively.The tumor size cutoff value between the low and high malignant potential groups was 4.05 cm,and the sensitivity and specificity were 93.5%and 84.2%,respectively.CONCLUSION CT features,including tumor size,growth patterns,and lesion contours,were predictors of malignant potential for primary gastric GISTs. 展开更多
关键词 Computed tomography Gastrointestinal stromal tumor Risk stratification Stomach
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Long-Term Outcomes after Coronary Artery Bypass Grafting with Risk Stratification
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作者 Ayman R. Abdelrehim Ibraheem H. Al Harbi +10 位作者 Hasan I. Sandogji Faisal A. Alnasser Mohammad Nizam S. H. Uddin Fatma A. Taha Fareed A. Alnozaha Fath A. Alabsi Shakir Ahmed Waheed M. Fouda Amir A. El Said Tousif Khan Ahmed M. Shabaan 《World Journal of Cardiovascular Diseases》 2023年第8期493-510,共18页
Background: Risk stratification of long-term outcomes for patients undergoing Coronary artery bypass grafting has enormous potential clinical importance. Aim: To develop risk stratification models for predicting long-... Background: Risk stratification of long-term outcomes for patients undergoing Coronary artery bypass grafting has enormous potential clinical importance. Aim: To develop risk stratification models for predicting long-term outcomes following coronary artery bypass graft (CABG) surgery. Methods: We retrospectively revised the electronic medical records of 2330 patients who underwent adult Cardiac surgery between August 2016 and December 2022 at Madinah Cardiac Center, Saudi Arabia. Three hundred patients fulfilled the eligibility criteria of CABG operations with a complete follow-up period of at least 24 months, and data reporting. The collected data included patient demographics, comorbidities, laboratory data, pharmacotherapy, echocardiographic parameters, procedural details, postoperative data, in-hospital outcomes, and follow-up data. Our follow-up was depending on the clinical status (NYHA class), chest pain recurrence, medication dependence and echo follow-up. A univariate analysis was performed between each patient risk factor and the long-term outcome to determine the preoperative, operative, and postoperative factors significantly associated with each long-term outcome. Then a multivariable logistic regression analysis was performed with a stepwise, forward selection procedure. Significant (p < 0.05) risk factors were identified and were used as candidate variables in the development of a multivariable risk prediction model. Results: The incidence of all-cause mortality during hospital admission or follow-up period was 2.3%. Other long-term outcomes included all-cause recurrent hospitalization (9.8%), recurrent chest pain (2.4%), and the need for revascularization by using a stent in 5 (3.0%) patients. Thirteen (4.4%) patients suffered heart failure and they were on the maximum anti-failure medications. The model for predicting all-cause mortality included the preoperative EF ≤ 35% (AOR: 30.757, p = 0.061), the bypass time (AOR: 1.029, p = 0.003), and the duration of ventilation following the operation (AOR: 1.237, p = 0.021). The model for risk stratification of recurrent hospitalization comprised the preoperative EF ≤ 35% (AOR: 6.198, p p = 0.023), low postoperative cardiac output (AOR: 3.622, p = 0.007), and the development of postoperative atrial fibrillation (AOR: 2.787, p = 0.038). Low postoperative cardiac output was the only predictor that significantly contributed to recurrent chest pain (AOR: 11.66, p = 0.004). Finally, the model consisted of low postoperative cardiac output (AOR: 5.976, p < 0.001) and postoperative ventricular fibrillation (AOR: 4.216, p = 0.019) was significantly associated with an increased likelihood of the future need for revascularization using a stent. Conclusions: A risk prediction model was developed in a Saudi cohort for predicting all-cause mortality risk during both hospital admission and the follow-up period of at least 24 months after isolated CABG surgery. A set of models were also developed for predicting long-term risks of all-cause recurrent hospitalization, recurrent chest pain, heart failure, and the need for revascularization by using stents. 展开更多
关键词 Coronary Artery Bypass Graft Long-Term Mortality Risk Prediction Model Risk stratification
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The Impact of Climate Change on the Stratification of Coastal Areas of the Euboean Gulf and the Diffusion of Urban Wastewater in Them
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作者 Evangelos Tsirogiannis Panagiotis Angelidis 《Computational Water, Energy, and Environmental Engineering》 2023年第3期1-26,共26页
Hydrodynamic circulation in a marine environment, characterized by the influence of strong tides, atmospheric loading and bathymetry, is a complex phenomenon. The physical and hydrodynamic characteristics of this flow... Hydrodynamic circulation in a marine environment, characterized by the influence of strong tides, atmospheric loading and bathymetry, is a complex phenomenon. The physical and hydrodynamic characteristics of this flow are absolutely crucial for the vertical mixing of the sea masses and consequently for the mixing of their physico-chemical parameters, such as nutrients and oxygen, as well as for the diffusion and dispersion of passive pollutants, the recharge of the waters and the general environmental situation. This paper examines the effect of a future increase in mean air temperature on the water column stratification of coastal areas of interest, which are subject to the above loadings and receive treated urban wastewater, and how this increase could affect their diffusion and mixing of conservative pollutants contained therein. 展开更多
关键词 3D Modelling stratification SEWAGE Euboean Gulf Greece Climate Change
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