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Research in Astronomy and Astrophysics 2022年第3期22卷 178-185页

作者： ming-ming meng Ying D.Liu Chong Chen Rui Wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The S-shaped magnetic structure in the solar wind formed by the twisting of magnetic field lines is called a switchback,whose main characteristics are the reversal of the magnetic field and the significant increase in the solar wind radial *** identify 242 switchbacks during the first two encounters of Parker Solar *** methods are applied to analyze the distribution and the rotation angle and direction of the magnetic field rotation of the *** diameter of switchbacks is estimated with a minimum variance analysis(MVA)method based on the assumption of a cylindrical magnetic *** also make a comparison between switchbacks from inside and the boundary of coronal *** main conclusions are as follows:(1)the rotation angles of switchbacks observed during the first encounter seem larger than those of the switchbacks observed during the second encounter in general;(2)the tangential component of the velocity inside the switchbacks tends to be more positive(westward)than in the ambient solar wind;(3)switchbacks are more likely to rotate clockwise than counterclockwise,and the number of switchbacks with clockwise rotation is 1.48 and 2.65 times those with counterclockwise rotation during the first and second encounters,respectively;(4)the diameter of switchbacks is about 10;km on average and across five orders of magnitude(10^(3)–10^(7)km).

关键词： ISM:magnetic fields methods:statistical (Sun:)solar wind

Development and validation of an online calculator to predict the pathological nature of colorectal tumors

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World Journal of Gastrointestinal Oncology 2023年第7期15卷 1271-1282页

作者： Ya-Dan Wang Jing Wu Bo-Yang Huang Chun-Mei Guo Cang-Hai Wang Hui Su Hong Liu Miao-Miao Wang Jing Wang Li Li Peng-Peng Ding ming-ming meng Department of Gastroenterology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseasesBeijing Digestive Disease CenterBeijing Key Laboratory for Precancerous Lesion of Digestive DiseasesBeijing 100050China Department of Gastroenterology Beijing Shijitan Hospitalthe Ninth Clinical Medicine Peking UniversityBeijing 100038China

BACKGROUND No single endoscopic feature can reliably predict the pathological nature of colorectal tumors(CRTs).AIM To establish and validate a simple online calculator to predict the pathological nature of CRTs based on white-light *** This was a single-center *** the identification stage,530 consecutive patients with CRTs were enrolled from January 2015 to December 2021 as the derivation *** regression analysis was performed.A novel online calculator to predict the pathological nature of CRTs based on white-light images was established and verified *** the validation stage,two series of 110 images obtained using white-light endoscopy were distributed to 10 endoscopists[five highly experienced endoscopists and five less experienced endoscopists(LEEs)]for external validation before and after systematic *** A total of 750 patients were included,with an average age of 63.6±10.4 *** colorectal cancer(ECRC)was detected in 351(46.8%)*** size,left semicolon site,rectal site,acanthosis,depression and an uneven surface were independent risk factors for *** C-index of the ECRC calculator prediction model was 0.906(P=0.225,Hosmer-Lemeshow test).For the LEEs,significant improvement was made in the sensitivity,specificity and accuracy(57.6%vs 75.5%;72.3%vs 82.4%;64.2%vs 80.2%;P<0.05),respectively,after training with the ECRC online calculator prediction *** A novel online calculator including tumor size,location,acanthosis,depression,and uneven surface can accurately predict the pathological nature of ECRC.

关键词： Pathological nature Colorectal tumors White-light endoscopy Online calculator Early colorectal cancer

Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 491-502页

作者： Yi-Fan Lv Bing Zhu ming-ming meng Yi-Fan Wu Cheng-Bin Dong Yu Zhang Bo-Wen Liu Shao-Li You Sa Lv Yong-Ping Yang Fu-Quan Liu Liver Disease Minimally Invasive Diagnosis and Treatment Center Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Liver Vascular Disease Diagnosis and Treatment Center The Fifth Medical Center of Chinese People's Liberation Army General HospitalBeijing 100039China

BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ***,there have been no specific studies on predicting long-term survival after TIPS *** To establish a model to predict long-term survival in patients with hepatitis cirrhosis after *** A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS *** univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after ***,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)***,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing *** The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS *** NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation ***,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients

关键词： Transjugular intrahepatic portosystemic shunt Long-term survival Predictive model

Endoscopic classification and pathological features of primary intestinal lymphangiectasia

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World Journal of Gastroenterology 2022年第22期28卷 2482-2493页

作者： ming-ming meng Kui-Liang Liu Xin-Ying Xue Kun Hao Jian Dong Chun-Kai Yu Hong Liu Cang-Hai Wang Hui Su Wu Lin Guo-Jun Jiang Nan Wei Ren-Gui Wang Wen-Bin Shen Jing Wu Department of Gastroenterology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Respiratory and Critical Care Medicine Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Departments of Lymphatic Surgery Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Departments of Radiology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Departments of Pathology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

BACKGROUND The appearance of the intestinal mucosa during endoscopy varies among patients with primary intestinal lymphangiectasia(PIL).AIM To classify the endoscopic features of the intestinal mucosa in PIL under endoscopy,combine the patients’imaging and pathological characteristics of the patients,and explain their *** We retrospectively analyzed the endoscopic images of 123 patients with PIL who were treated at the hospital between January 1,2007 and December 31,*** compared and analyzed all endoscopic images,classified them into four types according to the endoscopic features of the intestinal mucosa,and analyzed the post-lymphographic computed tomography(PLCT)and pathological characteristics of each *** According to the endoscopic features of PIL in 123 patients observed during endoscopy,they were classified into four types:nodular-type,granular-type,vesicular-type,and *** showed diffuse thickening of the small intestinal wall,and no contrast agent was seen in the small intestinal wall and mesentery in the patients with nodular and granular *** agent was scattered in the small intestinal wall and mesentery in the patients with vesicular and edematous *** of the small intestinal mucosal pathology revealed that nodular-type and granulartype lymphangiectasia involved the small intestine mucosa in four layers,whereas ectasia of the vesicular-and edematous-type lymphatic vessels largely involved the lamina propria mucosae,submucosae,and muscular *** Endoscopic classification,combined with the patients’clinical manifestations and pathological examination results,is significant and very useful to clinicians when scoping patients with suspected PIL.

关键词： Primary intestinal lymphangiectasia Endoscopic features Post-lymphangiographic computed tomography Pathology

Correlation of pressure gradient in three hepatic veins with portal pressure gradient

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World Journal of Clinical Cases 2022年第14期10卷 4460-4469页

作者： Hao-Yu Wang Qing-Kun Song Zhen-Dong Yue Lei Wang Zhen-Hua Fan Yi-Fan Wu Cheng-Bin Dong Yu Zhang ming-ming meng Ke Zhang Li Jiang Hui-Guo Ding Yue-Ning Zhang Yong-Ping Yang Fu-Quan Liu Department of Oncology The 9^(th)Clinical Medical College&Beijing Shijitan HospitalPeking UniversityBeijing 100038China Division of Clinical Epidemiology and Evidence-Based Medicine Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Interventional Therapy Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Gastroenterology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of General Surgery Beijing Ditan HospitalCapital Medical UniversityBeijing 100102China Department of Gastroenterology and Hepatology Beijing You'an HospitalCapital Medical UniversityBeijing 100069China Department of Therapeutic Research for Liver Cancer The Fifth Medical Center of Chinese PLA General HospitalBeijing 100039China

BACKGROUND The liver is one of the most important organs in the human body,with functions such as detoxification,digestion,and blood *** terms of vascular anatomy,the liver is divided into the left and the right liver by the main portal vein,and there are three hepatic efferent veins(right,middle,and left)and two portal *** with impaired liver function have increased intrahepatic vascular resistance and splanchnic vasodilation,which may lead to an increase in the portal pressure gradient(PPG)and cause portal hypertension(PHT).In order to measure the increased pressure gradient of portal vein,the hepatic venous pressure gradient(HVPG)can be measured to reflect it in clinical *** accuracy of PPG measurements is directly related to patient *** To analyze the correlation between HVPG of three hepatic veins and PPG in patients with *** From January 2017 to December 2019,102 patients with PHT who met the inclusion criteria were evaluated during the transjugular intrahepatic portosystemic shunt procedure and *** The mean HVPG of the middle hepatic vein was 17.47±10.25 mmHg,and the mean HVPG of the right and left hepatic veins was 16.34±7.60 and 16.52±8.15 mmHg,*** average PPG was 26.03±9.24 *** correlation coefficient and coefficient of determination of the right hepatic vein,middle hepatic vein,and left hepatic vein were 0.15 and 0.02(P=0.164);0.25 and 0.05(P=0.013);and 0.14 and 0.02(P=0.013),*** mean wedged hepatic vein/venous pressure(WHVP)of the middle and left hepatic veins was similar at 29.71±12.48 and 29.1±10.91 mmHg,respectively,and the mean WHVP of the right hepatic vein was slightly lower at 28.01±8.95 *** mean portal vein pressure was 34.11±8.56 *** correlation coefficient and coefficient of determination of the right hepatic vein,middle hepatic vein,and left hepatic vein were 0.26 and 0.07(P=0.009);0.38 and 0.15(P<0.001);and 0.26 and 0.07(P=0.008),respecti

关键词： Portal hypertension Portal pressure gradient Hepatic venous pressure gradient Free hepatic venous pressure

Transjugular intrahepatic portosystemic shunt with radioactive seed strand for main portal vein tumor thrombosis with cirrhotic portal hypertension

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World Journal of Gastrointestinal Surgery 2022年第6期14卷 567-579页

作者： Xuan-Hui Yan Zhen-Dong Yue Hong-Wei Zhao Lei Wang Zhen-Hua Fan Yi-Fan Wu ming-ming meng Ke Zhang Li Jiang Hui-Guo Ding Yue-Ning Zhang Yong-Ping Yang Fu-Quan Liu Department of Interventional Therapy Peking University Ninth School of Clinical MedicineBeijing Shijitan HospitalBeijing 100038China Department of Interventional Therapy Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Interventional Therapy Beijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Gastroenterology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of General Surgery Beijing Ditan HospitalCapital Medical UniversityBeijing 100102China Department of Gastroenterology Beijing You'an HospitalCapital Medical UniversityBeijing 100069China Department of Liver Disease Digestion Center Beijing You'an HospitalCapital Medical UniversityBeijing 100069China Department of Liver Disease The Fifth Medical Center of Chinese PLA General HospitalBeijing 100039China

BACKGROUND Patients with hepatocellular carcinoma complicated with main portal vein tumor thrombosis(mPVTT) and cirrhotic portal hypertension(CPH) have an extremely poor prognosis, and there is a lack of a clinically effective treatment *** To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt(TIPS)combined with radioactive seed strand for the treatment of mPVTT patients with *** The clinical data of 83 consecutive patients who underwent TIPS combined with 125I seed strand placement for mPVTT and CPH from January 2015 to December 2018 were retrospectively reviewed. Procedure-related data(success rate, relief of portal vein pressure and CPH symptoms,and adverse events), PVTT response, and patient survival were assessed through a 2-year *** The success rate was 100.0% without perioperative death or procedure-related severe adverse events. The mean portal vein pressure was significantly decreased after the procedure(22.25 ± 7.33mmHg vs 35.12 ± 7.94 mmHg, t = 20.61, P < 0.001). The symptoms of CPH were all effectively relieved within 1 mo. The objective response rate of PVTT was 67.5%. During a mean follow-up of 14.5 ± 9.4 mo(range 1-37 mo), the cumulative survival rates at 6, 12 and 24 mo were 83.1%, 49.7%,and 21.8%, respectively. The median survival time was 12.0 ± 1.3 mo(95% confidence interval: 9.5-14.5). In multivariate Cox regression analysis, body mass index, Child-Pugh grade, cTNM stage,and PVTT response were independent prognostic factors(P < 0.05).CONCLUSION TIPS combined with radioactive seed strand might be effective and safe in treating mPVTT patients with CPH.

关键词： Transjugular intrahepatic portosystemic shunt Radioactive seed strand Portal vein tumor thrombosis Hepatocellular carcinoma Cirrhotic portal hypertension Cirrhosis

Progress of research in the application of ultrasound technology for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2823-2837页

作者： Qiuquan Cai Lianghui meng Meina Quan Ling Wang Jing Ren Chenguang Zheng Jiajia Yang Dong ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Innovation Center for Neurological Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Brain-Computer Interaction and Human-Machine Fusion Haihe Laboratory Tianjin UniversityTianjinChina Tianjin Key Laboratory of Brain Science and Neural Engineering Tianjin UniversityTianjinChina

Alzheimer’s disease is a common neurodegenerative disorder defined by decreased reasoning abilities,memory loss,and cognitive *** presence of the blood-brain barrier presents a major obstacle to the development of effective drug therapies for Alzheimer’s *** use of ultrasound as a novel physical modulation approach has garnered widespread attention in recent *** a safe and feasible therapeutic and drug-delivery method,ultrasound has shown promise in improving cognitive *** article provides a summary of the application of ultrasound technology for treating Alzheimer’s disease over the past 5 years,including standalone ultrasound treatment,ultrasound combined with microbubbles or drug therapy,and magnetic resonance imaging-guided focused ultrasound *** is placed on the benefits of introducing these treatment methods and their potential *** found that several ultrasound methods can open the blood-brain barrier and effectively alleviate amyloid-βplaque *** believe that ultrasound is an effective therapy for Alzheimer’s disease,and this review provides a theoretical basis for future ultrasound treatment methods.

关键词： Alzheimer’s disease blood-brain barrier drugs magnetic resonance imaging-guided focused ultrasound microbubbles scanning ultrasound ultrasound ultrasound stimulation

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以单发食管溃疡为首发表现白塞病1例

世界华人消化杂志 2017年第19期25卷 1798-1802页

作者：王芸吴静刘揆亮宿慧孟明明郭春梅北京大学第九临床学院北京世纪坛医院消化内科北京市100038

白塞病单一食管受累临床少见,表现不典型,诊断困难.本例患者入院曾拟诊为"食管癌?",经治疗前后多次复查胃镜、超声内镜,并结合患者病史及相关检查结果 ,最终诊断为单发食管白塞病.白塞病尤其是单发食管白塞病诊断有赖于典型的临床特征... 详细信息

白塞病单一食管受累临床少见,表现不典型,诊断困难.本例患者入院曾拟诊为"食管癌?",经治疗前后多次复查胃镜、超声内镜,并结合患者病史及相关检查结果 ,最终诊断为单发食管白塞病.白塞病尤其是单发食管白塞病诊断有赖于典型的临床特征和对各种临床表现的综合分析.纤维超声内镜在评价食管白塞病病变浸润深度及随访过程中对治疗效果的评价有其独特优势.

关键词：食管溃疡白塞病超声内镜

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

高纯3,3'-二氨基-4,4'-氧化偶氮呋咱(DAOAF)的合成工艺

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含能材料 2017年第10期25卷 838-842页

作者：王小旭张勇黄明陈明龙孟俞富索志荣杨海君李鸿波西南科技大学材料科学与工程学院四川绵阳621010 中国工程物理研究院化工材料研究所四川绵阳621999

以乙二醛和盐酸羟胺为原料,经一步法合成中间体3,4-二氨基呋咱(DAF),收率48.0%,纯度99.8%。在NaHCO_3溶液缓冲体系中,DAF经过硫酸氢钾(KHSO_5·0.5KHSO_4·0.5K_2SO_4)氧化制得3,3'-二氨基-4,4'-氧化偶氮呋咱(DAOAF),采用IR、~1H NMR、MS等对其结构进行确证,通过高效液相色谱的面积归一化法测定产品纯度并定性、定量分析产品中所含杂质。考查了氧化反应中反应物投料比、反应时间与温度对收率的影响,获得最佳合成工艺为:n(DAF)∶n(NaHCO_3)∶n(KHSO_5·0.5KHSO_4·0.5K_2SO_4)=1∶6∶4,反应时间5 h,反应温度20~25℃,粗品收率为84.1%,纯度98.2%。粗品DAOAF经HPLC分析确定杂质为DAF、副产物DAAF和ANF。粗品于95℃经DMF重结晶可有效除去杂质,从而制得高纯DAOAF(纯度99.6%),总回收率为86.6%。

关键词： 3,4二氨基呋咱(DAF) 3,3'-二氨基-4,4'-氧化偶氮呋咱(DAOAF) 合成