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Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital 被引量:1
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作者 Mu-Han Li Ge-Chong Ruan +9 位作者 Wei-Xun Zhou Xiao-Qing Li Sheng-Yu Zhang Yang Chen Xiao-Yin Bai Hong Yang Yu-Jie Zhang Peng-Yu Zhao Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2523-2537,共15页
BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis an... BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications. 展开更多
关键词 Autoimmune enteropathy Clinical manifestations Diagnostic criteria Pathological features Long-term prognosis
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Neurological Manifestations of Vitamin B12 Deficiency: About a Case
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作者 Emmanuel Yangatimbi Duval Lewis Grenaba +4 位作者 Josué Pierre Kinima Larissa Kpengougna Jacqueline Tchebemou Caprice Vivien Ndouellet Pascal Mbelesso 《Neuroscience & Medicine》 2024年第1期51-54,共4页
The authors report a case of deficient sensory neuropathy secondary to vitamin B12 deficiency, diagnosed in the neurology department of the Sino-Central African Friendship University Hospital in Bangui. The diagnosis ... The authors report a case of deficient sensory neuropathy secondary to vitamin B12 deficiency, diagnosed in the neurology department of the Sino-Central African Friendship University Hospital in Bangui. The diagnosis was made possible by electroneuromyography which showed subclinical neurological damage associated with hematological damage (anemia). Through this observation, we recall the diagnostic criteria of the disease in a context of difficult medical practice. . 展开更多
关键词 Neurological manifestations Vitamins B12 Central African Republic
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Rare extraintestinal manifestations of ulcerative colitis treated with dual biologic therapy:A case report
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作者 Aleksandra Filipiuk Maciej Gonciarz 《World Journal of Clinical Cases》 SCIE 2024年第23期5441-5447,共7页
BACKGROUND Ulcerative colitis(UC)is an idiopathic,chronic inflammatory bowel disease(IBD)most often located in the rectum,but may involve the entire colon.Extra intestinal manifestations(EIMs)occur with varying freque... BACKGROUND Ulcerative colitis(UC)is an idiopathic,chronic inflammatory bowel disease(IBD)most often located in the rectum,but may involve the entire colon.Extra intestinal manifestations(EIMs)occur with varying frequency depending on the affected organ.The most common ones are musculoskeletal EIMs,affecting up to 33%-40%of IBD patients.These include,among others,inflammatory back pain,tendinitis,plantar fasciitis and arthritis.Only a few case reports in literature discuss Achilles tendinitis.CASE SUMMARY This report describes a patient with UC and Achilles tendinitis in whom after many unsuccessful attempts of treatment with sulfasalazine,mesalazine,glucocorticosteroids,infliximab and tofacitinib,a complete UC remission and resolution of Achilles tendinitis were achieved with the use of dual biologic therapy(DBT)-ustekinumab and adalimumab(ADA).CONCLUSION This case mentions rare EIMs of UC and suggests that DBT may be an alternative for patient with ulcerative colitis and EIMs. 展开更多
关键词 Achilles tendinitis Dual biologic therapy Extraintestinal manifestations SPONDYLOARTHROPATHY Ulcerative colitis Case report
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Comparison of Oral Manifestations in Hospitalized COVID-19 Positive Patients and COVID-19 Negative Dental Outpatients. A Case Series Study and Literature Review
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作者 Flora Zervou-Valvi Emmanouil M. Valvis +5 位作者 Angeliki Giannopoulou Eleana Stoufi Charilaos Samaras Olga Spiropoulou Antonia Hadjicosta Smaragda Diamanti 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第3期225-250,共26页
Background: The Coronavirus disease 2019 (COVID-19) is a respiratory infectious disease, also named Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which can cause various systemic manifestations that po... Background: The Coronavirus disease 2019 (COVID-19) is a respiratory infectious disease, also named Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which can cause various systemic manifestations that pose a threat to human life. Oral lesions in patients with COVID-19 may appear during or after the illness and may or may not be a consequence of the viral infection. Objective: In this case series we compare the oral manifestations in hospitalized COVID-19 positive patients and COVID-19 negative dental outpatients. Methods: 60 hospitalized COVID-19 patients and 41 control patients, were examined for oral signs and symptoms. The controls were dental patients who visited the hospital for dental care without complaining of any problems related to the oral cavity itself. Results: We have observed a strong association between certain clinical findings and COVID-19, including alterations in taste (ageusia, dysgeusia, and hypogeusia), anosmia, hairy tongue, tongue imprints, red tongue, erythematous candidiasis, pseudomembranous candidiasis, and exfoliative cheilitis. A trend but not statistically significant association at the level of 5% was also noted for colored tongue, linea alba, and pale mucosa. On the contrary, fissured tongue and oral mucosa pigmentation were more frequent in the controls, statistically significant at the level of 5%. Conclusion: COVID-19 has been found to impact the oral cavity, resulting in various oral lesions that can be attributed to either the direct action of the virus or the patient’s immune response. 展开更多
关键词 Case Series COVID-19 SARS-CoV-2 Oral Lesions/manifestations Hospitalized Patients Control/Dental Patients
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The relationship between the distribution of HBcAg in liver cells and the pathological manifestations of the liver in 429 HBeAg-positive chronic HBV-infected individuals
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作者 Fan Nie Chang-Chun Zeng +4 位作者 Guang-Dong Tong Mu-Min Shao Xiao-Hua Le Xin Deng Da-Qiao Zhou 《Gastroenterology & Hepatology Research》 2024年第3期10-15,共6页
Background:The natural history of chronic HBV infection is typically characterized by four stages:the immune tolerance period,the immune clearance period,the immune control period,and the immune escape period.These st... Background:The natural history of chronic HBV infection is typically characterized by four stages:the immune tolerance period,the immune clearance period,the immune control period,and the immune escape period.These stages are associated with the distribution of HBcAg in liver cells;however,this relationship remains a topic of broad debate within the field of liver disease.To objectively and quantitatively measure the intracellular distribution of HBcAg,this paper aims to design a method referred to as the“layered evaluation method”and to examine its validation.Methods:The distribution of HBcAg in liver cells is assessed using Image Pro Plus image processing software,along with calculations of cytoplasmic and nuclear positive staining rates.Results:The findings indicate that the highest proportion of patients exhibited a positive cytoplasmic expression rate ranging from 0-2.5%.More than 40% of the total sample was categorized within the 0-2.5% positive nuclear expression range.The HBcAg cytoplasmic positive staining rates were classified into five levels:a cytoplasmic HBcAg positive staining rate of less than 0.05% is designated as level 0,indicating negative expression;a staining rate between 0.05% and 5% is classified as level 1;a rate from 5% to less than 10% is classified as level 2;a rate from 10% to less than 20% is classified as level 3;and a nuclear positivity rate exceeding 20% is classified as level 4.Conclusion:The inflammatory activity grade in these patients was positively correlated with the cytoplasmic distribution of HBcAg.Furthermore,the nuclear distribution rate of HBcAg was significantly higher in the G3 group compared to the other groups. 展开更多
关键词 distribution of HBcAg pathological manifestations of the liver positive staining rate
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X-ray Manifestations of Pneumoconiosis Patients and Differential Analysis with Pulmonary Tuberculosis
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作者 Gaocai XIONG Yuanfeng YANG +2 位作者 Wei ZHANG Mingbi LYU Tingqian LIU 《Agricultural Biotechnology》 CAS 2023年第3期75-78,共4页
[Objectives]This study was conducted to explore the X-ray manifestations of pneumoconiosis patients and differentiation from pulmonary tuberculosis.[Methods]Retrospective analysis was conducted on 103 patients who und... [Objectives]This study was conducted to explore the X-ray manifestations of pneumoconiosis patients and differentiation from pulmonary tuberculosis.[Methods]Retrospective analysis was conducted on 103 patients who underwent lung examinations,including 47 cases of pneumoconiosis and 56 cases of pulmonary tuberculosis.The differences in nodule characteristics and accompanying cavity sign between pneumoconiosis and pulmonary tuberculosis were compared.[Results]The X-ray manifestations of pneumoconiosis patients mainly included various forms of lung images,which were uneven in density,and had blurry edges,and sometimes thickening of lung markings and reduction of lung volume could be observed.The acinar nodules observed in X-ray films of patients with hematogenous disseminated pulmonary tuberculosis appeared petal like.The uniformity of nodule appearance such as nodule distribution,nodule density,and nodule size was significantly lower in pneumoconiosis than in hematogenous disseminated pulmonary tuberculosis,showing a statistical significance(P<0.05).The diameter of cavities in patients with pneumoconiosis accompanied by cavity sign[(0.64±0.13 vs 3.37±0.95)cm]was lower than that in patients with secondary pulmonary tuberculosis accompanied by cavity sign.There was a significant difference in the thickness of the cavity wall between the two diseases,and patients with pneumoconiosis accompanied by cavity sign had a higher rate of thick wall cavities(>3 mm).The X-ray manifestations of pneumoconiosis and tuberculosis were relatively similar,but the distribution,density and size of nodules in pneumoconiosis were relatively uneven,and the patients accompanied by cavity sign had smaller cavity diameter and higher rate of thick-walled cavities.[Conclusions]This study provides a reference for the clinical differential diagnosis of pneumoconiosis and pulmonary tuberculosis. 展开更多
关键词 PNEUMOCONIOSIS Pulmonary tuberculosis x-ray Cavity sign Differential analysis
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Coagulation abnormalities and their relationship with bleeding manifestations in patients with dengue-A single center observational study 被引量:2
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作者 Govind R.Patel Indu Thanvi +1 位作者 Mohammad Nadeem Rahul Kanwaria 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第2期65-71,共7页
Objective:To evaluate coagulation abnormalities and their relationship with bleeding manifestations among patients with dengue.Methods:This observational study was conducted on 292 adult dengue patients who were admit... Objective:To evaluate coagulation abnormalities and their relationship with bleeding manifestations among patients with dengue.Methods:This observational study was conducted on 292 adult dengue patients who were admitted to a tertiary care hospital of Western India from July 2021 to June 2022.Coagulation tests including prothrombin time(PT),international normalized ratio(INR),activated partial thromboplastin time(aPTT),fibrinogen,and D-dimer were performed.Patients were monitored for bleeding manifestations.Results:Coagulation abnormalities were reported in 42.8%of the patients.Overall,prolonged aPTT was the most common coagulation abnormality(40.8%),followed by low fibrinogen(38.7%),raised D-dimer(31.2%),raised INR(26.0%)and prolonged PT(19.2%).Bleeding manifestations were present in 19.9%patients.PT,INR,aPTT and D-dimer levels were significantly higher(P<0.01)and fibrinogen level was significantly lower(P<0.001)in patients with bleeding compared to patients without bleeding.Patients with bleeding had a significantly higher rate of all coagulation abnormalities than patients without bleeding(P<0.01).Conclusions:Patients with bleeding showed a significantly higher frequency of coagulation abnormalities compared to patients without bleeding.Patients with dengue should be assessed for coagulation abnormalities. 展开更多
关键词 DENGUE Coagulation abnormalities Coagulation parameters Prothrombin time Activated partial thromboplastin time Bleeding manifestations
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X-ray在鱼体组织及微量元素检测中的应用
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作者 宋一帆 张胜茂 +4 位作者 张衡 唐峰华 张寒野 石永闯 崔雪森 《应用光学》 CAS 北大核心 2024年第1期166-176,共11页
鱼类硬质组织物,特别是骨骼支持鱼体和保护其体内器官的组织,对其进行特征检测分析是研究鱼类游泳运动、鱼类解剖、鱼体建模等的数据基础。随着X-ray技术的发展和国产设备的广泛应用,其仪器设备成本明显降低,使得X-ray在渔业研究与自动... 鱼类硬质组织物,特别是骨骼支持鱼体和保护其体内器官的组织,对其进行特征检测分析是研究鱼类游泳运动、鱼类解剖、鱼体建模等的数据基础。随着X-ray技术的发展和国产设备的广泛应用,其仪器设备成本明显降低,使得X-ray在渔业研究与自动化生产中的应用成为可能。首先介绍了X-ray技术的基本原理与其在鱼体组织检测中的应用,X-ray技术在鱼体组织及微量元素检测中的应用主要分为鱼类组织器官的无损检测和鱼体微量元素检测两部分,其中分别介绍了包括照相法、数字成像法、衍射技术和吸收光谱法等X-ray技术;然后综述其在鱼体组织器官建模、鱼骨检测、鱼类化石研究、鱼耳石分析和鱼体微量元素检测方面的应用,总结了Xray在渔业领域应用中存在的问题;最后对X-ray的渔业应用方向进行展望。 展开更多
关键词 x-ray 鱼体骨骼 鱼类耳石 鱼体建模 鱼体微量元素
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Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath 被引量:2
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作者 Jin Guo TianRan Sun +6 位作者 San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang 《Earth and Planetary Physics》 EI CSCD 2024年第1期47-58,共12页
Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging ... Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered. 展开更多
关键词 MAGNETOPAUSE x-ray emissivity x-ray imaging SMILE global hybrid-PIC simulation
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The Soft X-ray Imager(SXI)on the SMILE Mission 被引量:4
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作者 S.Sembay A.L.Alme +83 位作者 D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang 《Earth and Planetary Physics》 EI CSCD 2024年第1期5-14,共10页
The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese... The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in 2025.SXI is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit.SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere.SWCX provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field lines.The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours.SXI is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States. 展开更多
关键词 Soft x-ray Imaging micropore optics large area CCD
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Two methods for separating the magnetospheric solar wind charge exchange soft X-ray emission from the diffuse X-ray background 被引量:2
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作者 YingJie Zhang TianRan Sun +5 位作者 JenniferACarter WenHao Liu Steve Sembay ShuiNai Zhang Li Ji Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期119-132,共14页
Solar wind charge exchange(SWCX)is the process of solar wind high-valence ions exchanging charges with neutral components and generating soft X-rays.Recently,detecting the SWCX emission from the magnetosphere is propo... Solar wind charge exchange(SWCX)is the process of solar wind high-valence ions exchanging charges with neutral components and generating soft X-rays.Recently,detecting the SWCX emission from the magnetosphere is proposed as a new technique to study the magnetosphere using panoramic soft X-ray imaging.To better prepare for the data analysis of upcoming magnetospheric soft X-ray imaging missions,this paper compares the magnetospheric SWCX emission obtained by two methods in an XMM-Newton observation,during which the solar wind changed dramatically.The two methods differ in the data used to fit the diffuse X-ray background(DXB)parameters in spectral analysis.The method adding data from the ROSAT All-Sky Survey(RASS)is called the RASS method.The method using the quiet observation data is called the Quiet method,where quiet observations usually refer to observations made by the same satellite with the same target but under weaker solar wind conditions.Results show that the spectral compositions of magnetospheric SWCX emission obtained by the two methods are very similar,and the changes in intensity over time are highly consistent,although the intensity obtained by the RASS method is about 2.68±0.56 keV cm^(-2)s^(-1)sr^(-1)higher than that obtained by the Quiet method.Since the DXB intensity obtained by the RASS method is about 2.84±0.74 keV cm^(-2)s^(-1)sr^(-1)lower than that obtained by the Quiet method,and the linear correlation coefficient between the difference of SWCX and DXB obtained by the two methods in diffe rent energy band is close to-1,the diffe rences in magnetospheric SWCX can be fully attributed to the diffe rences in the fitted DXB.The difference between the two methods is most significant when the energy is less than 0.7 keV,which is also the main energy band of SWCX emission.In addition,the difference between the two methods is not related to the SWCX intensity and,to some extent,to solar wind conditions,because SWCX intensity typically va ries with the solar wind.In summary,both methods are robust and reliable,and should be considered based on the best available options. 展开更多
关键词 solar wind charge exchange(SWCX) ROSAT All-Sky Survey(RASS) soft x-ray x-ray imaging MAGNETOSPHERE
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Pathogenesis,clinical manifestations,diagnosis,and treatment progress of achalasia of cardia
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作者 Ming-Yue Li Qing-Hua Wang +2 位作者 Run-Peng Chen Xiao-Fang Su Dong-Yang Wang 《World Journal of Clinical Cases》 SCIE 2023年第8期1741-1752,共12页
Achalasia cardia,type of esophageal dynamic disorder,is a relatively rare primary motor esophageal disease characterized by the functional loss of plexus ganglion cells in the distal esophagus and lower esophageal sph... Achalasia cardia,type of esophageal dynamic disorder,is a relatively rare primary motor esophageal disease characterized by the functional loss of plexus ganglion cells in the distal esophagus and lower esophageal sphincter.Loss of function of the distal and lower esophageal sphincter ganglion cells is the main cause of achalasia cardia,and is more likely to occur in the elderly.Histological changes in the esophageal mucosa are considered pathogenic;however,studies have found that inflammation and genetic changes at the molecular level may also cause achalasia cardia,resulting in dysphagia,reflux,aspiration,retrosternal pain,and weight loss.Currently,the treatment options for achalasia focus on reducing the resting pressure of the lower esophageal sphincter,helping to empty the esophagus and relieve symptoms.Treatment measures include botulinum toxin injection,inflatable dilation,stent insertion,and surgical myotomy(open or laparoscopic).Surgical procedures are often subject to controversy owing to concerns about safety and effectiveness,particularly in older patients.Herein,we review clinical epidemiological and experimental data to determine the prevalence,pathogenesis,clinical presentation,diagnostic criteria,and treatment options for achalasia to support its clinical management. 展开更多
关键词 Achalasia cardia PATHOGENESIS Clinical manifestations DIAGNOSIS Treatment
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Finding the magnetopause location using soft X-ray observations and a statistical inverse method 被引量:1
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作者 Gonzalo Cucho-Padin Hyunju Connor +2 位作者 Jaewoong Jung Brian Walsh David G.Sibeck 《Earth and Planetary Physics》 EI CSCD 2024年第1期184-203,共20页
Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the magneto... Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the magnetosphere.The spatial and temporal properties of the magnetopause,under varying solar and magnetospheric conditions,remain largely unknown because empirical studies using in-situ observations are challenging to interpret.Global wide field-of-view(FOV)imaging is the only means to simultaneously observe the spatial distribution of the plasma properties over the vast dayside magnetospheric region and,subsequently,quantify the energy transport from the interplanetary medium into the terrestrial magnetosphere.Two upcoming missions,ESA/CAS SMILE and NASA’s LEXI will provide wide-field imagery of the dayside magnetosheath in soft X-rays,an emission generated by charge exchange interactions between high charge-state heavy ions of solar wind origin and exospheric neutral atoms.High-cadence two-dimensional observations of the magnetosheath will allow the estimation of dynamic properties of its inner boundary,the magnetopause,and enable studies of its response to changes in the solar wind dynamic pressure and interplanetary magnetic field orientation.This work introduces a statistically-based estimation approach based on inverse theory to estimate the spatial distribution of magnetosheath soft X-ray emissivities and,with this,identify the location of the magnetopause over the Sun−Earth line.To do so,we simulate the magnetosheath structure using the MHD-based OpenGGCM model and generate synthetic soft X-ray images using LEXI’s orbit and attitude information.Our results show that 3-D estimations using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray images.Also,our proposed methodology shows that the accuracy of both three-dimensional(3-D)estimation and the magnetopause standoff distance calculation highly depends on the observational point. 展开更多
关键词 MAGNETOPAUSE soft x-ray TOMOGRAPHY
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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter 被引量:1
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作者 Hyangpyo Kim Hyunju K.Connor +9 位作者 Jaewoong Jung Brian M.Walsh David Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier 《Earth and Planetary Physics》 EI CSCD 2024年第1期173-183,共11页
The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective l... The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind conditions.To suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray images.In this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is maximized.Two assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause curvature.We create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson noise.We then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea ks.From the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground truth.Our method estimates RS with an accuracy of<0.3 RE when the solar wind density exceeds>10 cm-3.The accuracy improves for greater solar wind densities and during southward interplanetary magnetic fields.The method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field turnings.Consequently,the technique will enable quantitative analysis of the magnetopause motion and help reveal the dayside reconnection modes for dynamic solar wind conditions.This technique will suppo rt the LEXI and SMILE missions in achieving their scientific o bjectives. 展开更多
关键词 soft x-ray MAGNETOPAUSE RECONNECTION low-pass filter LEXI SMILE
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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation 被引量:1
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作者 S.Parsons D.J.Hall +4 位作者 O.Hetherington T.W.Buggey T.Arnold M.W.J.Hubbard A.Holland 《Earth and Planetary Physics》 EI CSCD 2024年第1期25-38,共14页
Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the sof... Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance level.Three CCDs have been characterised,the two flight devices and the flight spa re.This has been carried out at the Open University in a bespo ke cleanroom measure ment facility.The results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe rature.However at the nominal ope rating tempe rature(-120℃) it is within the procure ment specifications.Overall,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science mode.The se rial charge transfer inefficiency degrades with temperature in full frame mode.However any charge losses are recovered when binning/frame transfer is implemented. 展开更多
关键词 CCD soft x-ray imager characterisation SMILE
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Solar wind ion charge state distributions and compound cross sections for solar wind charge exchange X-ray emission 被引量:1
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作者 Dimitra Koutroumpa 《Earth and Planetary Physics》 EI CSCD 2024年第1期105-118,共14页
Solar Wind Charge eXchange X-ray(SWCX) emission in the heliosphere and Ea rth’s exosphere is a hard to avoid signal in soft Xray obse rvations of astrophysical targets.On the other hand,the X-ray imaging possibilitie... Solar Wind Charge eXchange X-ray(SWCX) emission in the heliosphere and Ea rth’s exosphere is a hard to avoid signal in soft Xray obse rvations of astrophysical targets.On the other hand,the X-ray imaging possibilities offered by the SWCX process has led to an increasing number of future dedicated space missions for investigating the solar wind-terrestrial inte ractions and magnetospheric interfaces.In both cases,accurate modelling of the SWCX emission is key to correctly interpret its signal,and remove it from obse rvations,when needed.In this paper,we compile solar wind abundance measurements from ACE for different solar wind types,and atomic data from literature,including charge exchange cross-sections and emission probabilities,used fo r calculating the compound cross-section a for the SWCX X-ray emission.We calculate a values for charge-exchange with H and He,relevant to soft X-ray energy bands(0.1-2.0 keV)for various solar wind types and solar cycle conditions. 展开更多
关键词 solar wind charge exchange x-rays MAGNETOSPHERE HELIOSPHERE
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Liver manifestations in COVID-19 patients:A review article
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作者 Mariana Helou Janane Nasr +2 位作者 Nour El Osta Elsy Jabbour Rola Husni 《World Journal of Clinical Cases》 SCIE 2023年第10期2189-2200,共12页
The coronavirus disease 2019(COVID-19)initially presented as a disease that affected the lungs.Then,studies revealed that it intricately affected disparate organs in the human body,with the liver being one of the most... The coronavirus disease 2019(COVID-19)initially presented as a disease that affected the lungs.Then,studies revealed that it intricately affected disparate organs in the human body,with the liver being one of the most affected organs.This review aimed to assess the association between COVID-19 and liver function,shedding light on its clinical implication.However,its exact pathophysiology remains unclear,involving many factors,such as active viral replication in the liver cells,direct cytotoxic effects of the virus on the liver or adverse reactions to viral antigens.Liver symptoms are mild-to-moderate transaminase elevation.In some patients,with underlying liver disease,more serious outcomes are observed.Thus,liver function should be meticulously considered in patients with COVID-19. 展开更多
关键词 COVID-19 Liver injury Liver disease Liver manifestations
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Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review 被引量:1
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作者 Yubo Huang Ning Xu +3 位作者 Huaile Lu Yang Ren Shilei Li Yandong Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1333-1349,共17页
High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Exten... High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Extensive studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural materials.Synchrotron X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on materials.Recently,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation processes.In this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are discussed.The factors that influence the deformation mechanisms of HEAs are also outlined.This review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress changes.Perspectives on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed. 展开更多
关键词 high-entropy alloys MICROSTRUCTURES micromechanical behaviors synchrotron x-ray diffraction neutron diffraction
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Hepatobiliary manifestations following two-stages elective laparoscopic restorative proctocolectomy for patients with ulcerative colitis:A prospective observational study
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作者 Tamer A A M Habeeb Abdulzahra Hussain +24 位作者 Mauro Podda Pasquale Cianci Bruce Ramshaw Khaled Safwat Wesam M Amr Tamer Wasefy Alaa A Fiad Mohamed Ibrahim Mansour Adel Mahmoud Moursi GamalOsman Anass Qasem Mohamed Fawzy Mohamed Ibrahim Abo Alsaad Abd-Elfattah Kalmoush MohammedShaaban Nassar Fawzy M Mustafa Mahmoud Hassib Morsi Badawy Ahmed Hamdy Hamdi Elbelkasi Bassam Mousa Abd-Elrahman M Metwalli Walid A Mawla Mostafa M Elaidy Muhammad Ali Baghdadi Ahmed Raafat 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第2期234-248,共15页
BACKGROUND Hepatobiliary manifestations occur in ulcerative colitis(UC)patients.The effect of laparoscopic restorative proctocolectomy(LRP)with ileal pouch anal anastomosis(IPAA)on hepatobiliary manifestations is deba... BACKGROUND Hepatobiliary manifestations occur in ulcerative colitis(UC)patients.The effect of laparoscopic restorative proctocolectomy(LRP)with ileal pouch anal anastomosis(IPAA)on hepatobiliary manifestations is debated.AIM To evaluate hepatobiliary changes after two-stages elective laparoscopic restorative proctocolectomy for patients with UC.METHODS Between June 2013 and June 2018,167 patients with hepatobiliary symptoms underwent two-stage elective LRP for UC in a prospective observational study.Patients with UC and having at least one hepatobiliary manifestation who underwent LRP with IPAA were included in the study.The patients were followed up for four years to assess the outcomes of hepatobiliary manifestations.RESULTS The patients'mean age was 36±8 years,and males predominated(67.1%).The most common hepatobiliary diagnostic method was liver biopsy(85.6%),followed by Magnetic resonance cholangiopancreatography(63.5%),Antineutrophil cytoplasmic antibodies(62.5%),abdominal ultrasonography(35.9%),and Endoscopic retrograde cholangiopancreatography(6%).The most common hepatobiliary symptom was Primary sclerosing cholangitis(PSC)(62.3%),followed by fatty liver(16.8%)and gallbladder stone(10.2%).66.4%of patients showed a stable course after surgery.Progressive or regressive courses occurred in 16.8%of each.Mortality was 6%,and recurrence or progression of symptoms required surgery for 15%.Most PSC patients(87.5%)had a stable course,and only 12.5%became worse.Two-thirds(64.3%)of fatty liver patients showed a regressive course,while one-third(35.7%)showed a stable course.Survival rates were 98.8%,97%,95.8%,and 94%at 12 mo,24 mo,36 mo,and at the end of the follow-up.CONCLUSION In patients with UC who had LRP,there is a positive impact on hepatobiliary disease.It caused an improvement in PSC and fatty liver disease.The most prevalent unchanged course was PSC,while the most common improvement was fatty liver disease. 展开更多
关键词 COURSES Hepatobiliary manifestations Primary sclerosing cholangitis Restorative proctocolectomy
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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause 被引量:2
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作者 RongCong Wang JiaQi Wang +3 位作者 DaLin Li TianRan Sun XiaoDong Peng YiHong Guo 《Earth and Planetary Physics》 EI CSCD 2024年第1期133-154,共22页
Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosph... Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray imaging.However,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the magnetopause.The analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration models.This makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical models.We propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the magnetosphere.The idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch estimator.The Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the estimator.Experimental results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural similarity.The restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving the reconstruction results.Hence,the proposed technology may be feasible for processing SXI-simulated observation images. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft x-ray imager MAGNETOPAUSE image restoration
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