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Giant bile duct dilatation in newborn:A case report
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作者 Dong-Wen Quan Peng-Gang Li +1 位作者 Xiang-Hua Xu Shi-Qi Liu 《World Journal of Clinical Cases》 SCIE 2024年第6期1150-1156,共7页
BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical practice.Infants born with this condition often experience a poor overall health status,and the disease progresses rapidly,lead... BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical practice.Infants born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ dysfunction.The treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control bleeding.CASE SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant CBD.The patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 d.The abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of pregnancy.This finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary dilatation.No specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 cm.Based on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant CBD.Laparoscopic surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemostasis,as well as severe biliary system infection and ulceration.Consequently,there is a high likelihood of converting to laparotomy.The choice between surgical methods like hepaticojejunostomy(HJ)or hepaticoduodenostomy has not been standardized yet.However,we have achieved favorable outcomes using HJ.Preoperative management of inflammation,biliary drainage,liver function protection,and supportive treatment are particularly vital in improving children’s prognosis.After discharge,it is essential to conduct timely reexamination and close follow-up to identify potential complications. 展开更多
关键词 Acute cholangitis Congenital biliary dilation Laparoscopic surgery vs Open hepatic duct-jejunostomy Case report
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MEAN APPROXIMATION BY DILATATIONS IN BERGMAN SPACES ON THE UPPER HALF-PLANE
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作者 Ali ABKAR 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2204-2214,共11页
We study sufficient conditions on radial and non-radial weight functions on the upper half-plane that guarantee norm approximation of functions in weighted Bergman,weighted Dirichlet,and weighted Besov spaces on the u... We study sufficient conditions on radial and non-radial weight functions on the upper half-plane that guarantee norm approximation of functions in weighted Bergman,weighted Dirichlet,and weighted Besov spaces on the upper half-plane by dilatations and eventually by analytic polynomials. 展开更多
关键词 mean approximation dilatation non-radial weight angular weight weighted Bergman space weighted Besov space
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Failure transition of shear-to-dilation band of rock salt under triaxial stresses 被引量:1
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作者 Jianfeng Liu Xiaosong Qiu +3 位作者 Jianxiong Yang Chao Liang Jingjing Dai Yu Bian 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期56-64,共9页
Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily ... Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states. 展开更多
关键词 Rock salt Cyclic mechanical loading Shear band dilation band Underground gas storage(UGS)
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Distal Ureteric Dilatations Functioning as Urinary Reservoir in a Case of Ectopic Vesicae;A Case Report
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作者 Gashaw Messele Getahun 《Open Journal of Urology》 2023年第3期88-91,共4页
Background: Bladder exstrophy is a rare congenital malformation of the genitourinary system, with an estimated incidence of approximately 1 per 50,000 live births. Clinically, patients do not have capacity to accumula... Background: Bladder exstrophy is a rare congenital malformation of the genitourinary system, with an estimated incidence of approximately 1 per 50,000 live births. Clinically, patients do not have capacity to accumulate urine and urine continously leak. We present patient with partial storing capacity from the dialated distal ureters. A case of dialated distal ureters from an 8-year-old female patient with ectopic vesicae is described. The dialated ureters act as reservoir of urine where the patient is partially continent in the night time. These dialated ureters are the compensation for the literally absent bladder. During reconstruction, we observed that they can be used as an additional bladder volume reducing risk of reconstruction failure from tension. 展开更多
关键词 Bladder Exstrophy Ureteric dilatations
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Mechanical response and dilatancy characteristics of deep marble under different stress paths:A sight from energy dissipation
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作者 LIU Xiao-hui HAO Qi-jun +2 位作者 ZHENG Yu ZHANG Zhao-peng XUE Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2070-2086,共17页
Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses ... Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses on Jinping marble obtained from the Jinping Underground Laboratory in China at a depth of 2400 m.Various uniaxial and triaxial tests at different strain rates,along with constant confining pressure tests and reduced confining pressure tests under different confining pressures were conducted to analyze the mechanical response and dilatancy characteristics of the marble under four stress paths.Subsequently,a new empirical dilatancy coefficient is proposed based on the energy dissipation method.The results show that brittle failure characteristics of marble under uniaxial compression are more obvious with the strain rate increasing,and plastic failure characteristics of marble under triaxial compression are gradually strengthened.Furthermore,compared to the constant confining pressure,the volume expansion is relatively lower under unloading condition.The energy dissipation is closely linked to the process of dilatancy,with a rapid increase of dissipated energy coinciding with the beginning of dilatancy.A new empirical dilatancy coefficient is defined according to the change trend of energy dissipation rate curve,of which change trend is consistent with the actual dilatancy response in marble under different stress paths.The existing empirical and theoretical dilatancy models are analyzed,which shows that the empirical dilatancy coefficient based on the energy background is more universal. 展开更多
关键词 deep marble stress paths dilatANCY energy dissipation empirical dilatancy coefficient
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Long-term outcomes of urethral balloon dilation for anterior urethral stricture: A prospective cohort study
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作者 Ahmed M.Abdel Gawad Abhijit Patil +3 位作者 Abhishek Singh Arvind P.Ganpule Ravindra B.Sabnis Mahesh R.Desai 《Asian Journal of Urology》 CSCD 2024年第3期480-485,共6页
Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to rec... Objective:To prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation(BD)for 3 years to evaluate the long-term outcomes and to study factors that contribute to recurrence.Methods:This study included men who had urethral BD for significant anterior urethral stricture disease between January 2017 and March 2019.Data about the patient age,stricture characteristics,and recurrence date were recorded,along with information on postoperative indwelling catheter use and operative complications.Furthermore,information about the self-calibration procedure was collected and where available,free flow(FF)measurements during the follow-up period were recorded and analyzed.Success was defined as a lack of symptoms and acceptable FF rates(maximum flow rate>12 mL/s).Results:The final analysis was conducted on 187 patients.The mean follow-up period was 37 months.The long-term overall success rate at the end of our study was 66.8%.Our recurrence rate was 7.4%at 12 months,24.7%at 24 months,and reached 33.2%at the end of our study.The time to recurrence ranged from 91 days to 1635 days,with a mean of 670 days.The stricture-free survival was significantly shorter with lengthy peno-bulbar(p=0.031)and multiple strictures(p=0.015),and in the group of patients who were not committed to self-calibration protocol(p<0.011).However,post-procedural self-calibration was the most important factor that may have decreased the incidence of recurrence(odds ratioZ5.85).Adjuvant self-calibration after BD not only reduced the recurrence rate from 85.4%in the non-self-calibration group to 15.1%in the self-calibration one(p<0.001),but also improved the overall stricture-free survival and FF parameters. 展开更多
关键词 Balloon dilation Internal urethrotomy RECURRENCE SELF-CALIBRATION Urethral stricture
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An improved deep dilated convolutional neural network for seismic facies interpretation
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作者 Na-Xia Yang Guo-Fa Li +2 位作者 Ting-Hui Li Dong-Feng Zhao Wei-Wei Gu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1569-1583,共15页
With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural network... With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural networks.These intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic facies.However,the extensive demand for training data imposes limitations on their wider application.To overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training data.Additionally,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader range.The seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies boundaries.Comparative analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image segmentation.Obviously,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic facies.This approach holds significant potential for analyzing geological patterns and extracting valuable depositional information. 展开更多
关键词 Seismic facies interpretation dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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Polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes syndrome with dilated cardiomyopathy: A case report
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作者 Jia-Rong Li Lei-Yu Feng +2 位作者 Jian-Wei Li Yu Liao Fei-Qi Liu 《World Journal of Clinical Cases》 SCIE 2024年第3期601-606,共6页
BACKGROUND Polyneuropathy,organomegaly,endocrinopathy,M-protein,skin changes(POEMS)syndrome is a rare paraneoplastic syndrome that encompass multiple systems.The most common clinical symptoms of POEMS syndrome are pro... BACKGROUND Polyneuropathy,organomegaly,endocrinopathy,M-protein,skin changes(POEMS)syndrome is a rare paraneoplastic syndrome that encompass multiple systems.The most common clinical symptoms of POEMS syndrome are pro-gressive sensorimotor polyneuropathy,organ enlargement,endocrine disorders,darkening skin,a monoclonal plasma cell proliferative disorder,and lymph node hyperplasia.The organomegaly consists of hepatosplenomegaly and/or lym-phadenopathy;cases of cardiomyopathy are rare.Diagnoses are often delayed because of the atypical nature of the syndrome,exposing patients to possibly severe disability.Therefore,identifying atypical symptoms can improve the prognosis and quality of life among POEMS syndrome patients.lenalidomide and dexamethasone.CONCLUSION When patients with cardiomyopathy have systemic manifestations such as numb limbs and darkening skin,the POEMS syndrome is the most possible diagnosis. 展开更多
关键词 POLYNEUROPATHY organomegaly ENDOCRINOPATHY M-PROTEIN skin changes syndrome dilated cardiomyopathy LENALIDOMIDE Dexamethasone Case report
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Effect of endoscopic sphincterotomy and endoscopic papillary balloon dilation endoscopic retrograde cholangiopancreatographies on the sphincter of Oddi
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作者 Kai Fu Ying-Ying Yang +3 位作者 Hui Chen Guang-Xin Zhang Yan Wang Zhi Yin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1726-1733,共8页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects ... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP),with its clinical ad-vantages of less trauma and faster recovery,has become the primary treatment for choledocholithiasis.AIM To investigate the effects of different ERCP procedures on the sphincter of Oddi.METHODS The clinical data of 91 patients who underwent ERCP at Yixing Hospital of Traditional Chinese Medicine between February 2018 and February 2021 were analyzed retrospectively.The patients were divided into endoscopic sphinc-terotomy(EST,n=24)and endoscopic papillary balloon dilation(EPBD,n=67)groups.The duration of operation,pancreatic development,pancreatic sphinc-terotomy,intubation difficulties,stone recurrence,and incidence of reflux cho-langitis and cholecystitis were statistically analyzed in patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction in the EST and EPBD groups.RESULTS Differences in hypertension,diabetes,increased bilirubin,small diameter of the common bile duct,or ampullary diverticulum between the two groups were not significant.Statistically significant differences were observed between the two groups concerning sex and age(<60 years).Patients with a history of choledocholithiasis,pancreatitis,and Oddi sphincter dysfunction were higher in the EST group than in the EPBD group.The number of cases of pancreatic development,pancreatic duct sphincterotomy,and difficult intubation were higher in the EST group than in the EPBD group.The number of Oddi’s sphincter manometries,ERCP surgical outcomes,and guidewires entering the pancreatic duct several times in EST group were lower than those in the EPBD group.The numbers of stone recurrences,reflux cholangitis,and cholecystitis were higher in the EST group than in the EPBD group.CONCLUSION In summary,common bile duct stones,pancreatitis history,and multiple guided wire introductions into the pancreatic duct are independent risk factors for EST and EPBD.Based on this evidence,this study can provide actionable insights for clinicians and researchers. 展开更多
关键词 ODDI CHOLANGIOPANCREATOGRAPHY Endoscopic retrograde Risk factors Endoscopic sphincterotomy Endoscopic papillary balloon dilation
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Clinical efficacy of laparoscopic cholecystectomy combined with endoscopic papillary balloon dilation in treatment of gallbladder stones with common bile duct stones: A retrospective study
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作者 Hong-Dan Liu Qi Zhang +1 位作者 Wen-Si Xu Shuang Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1700-1708,共9页
BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic ... BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is controversial.AIM To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical methods.Surgery-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two groups.RESULTS Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST group.Intraoperative hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(P<0.05).The rate of total complications of the two groups was 9.80%and 17.65%,respectively,and the difference was not statistically significant.No serious complications occurred in either group.At 48 h postoperatively,the expression levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).At 3 d postoperatively,the expression levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(P<0.05).CONCLUSION LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery. 展开更多
关键词 Gallbladder stone Common bile duct stone Endoscopic papillary balloon dilation Laparoscopic cholecystectomy Endoscopic sphincterotomy
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Balloon dilation of congenital perforated duodenal web in newborns: Evaluation of short and long-term results
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作者 Kirill Marakhouski Elena Malyshka +5 位作者 Katsiaryna Nikalayeva Larysa Valiok Aleh Pataleta Kiryl Sanfirau Aliaksandr Svirsky Vasily Averin 《World Journal of Gastrointestinal Endoscopy》 2024年第6期343-349,共7页
BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To pre... BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To present our experience of balloon dilatation of a perforated duodenal memb-rane in newborns with ICDO.METHODS Five newborns who underwent balloon dilatation of the CPDW along a prein-stalled guidewire between 2021 and 2023 were included.Nineteen newborns diagnosed with ICDO who underwent laparotomy were included in the control group.RESULTS In all cases,good anatomical and clinical results were obtained.In three cases,a follow-up study was conducted after 1 year.The average time to start enteral feeding per os was significantly earlier in the study group(4.4 d)than in the laparotomic group(21.2 days;P<0.0001).The time spent by patients in the intensive care unit and hospital after balloon dilatation was also significantly shorter.We determined the selection criteria for possible and effective CPDW balloon dilatation in newborns as follows:(1)Presence of dynamic radiographic signs of the passage of a radiopaque substance beyond the zone of narrowing or radiographic signs of pneumatisation of the duodenum and small bowel distal to the web;(2)presence of endoscopic signs of CPDW;(3)successful cannulation with a guidewire performed parallel to the endoscope,with holes in the congenital duodenal web;and(4)successful positioning of the balloon performed along a freestanding guidewire on the web.CONCLUSION Strictly following selection criteria for newborns with ICDO caused by CPDW ensures that endoscopic balloon dilatation using a pre-installed guidewire is safe and effective and shows good 1-year follow-up results. 展开更多
关键词 NEWBORNS Congenital duodenal obstruction Perforated duodenal membrane ENDOSCOPY Balloon dilation
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Bioinformatics Analysis of the Relationship between Dilated Cardiomyopathy and Chronic Heart Failure
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作者 Lanqing Yu Haidong Zhou +8 位作者 Bailu Deng Jiaochang Wei Mei Zhang Chongyao Xu Guiyun Wei Junxiu Zhou Jun Huang Qi Lu Shaowu Ye 《Journal of Biosciences and Medicines》 2024年第8期333-346,共14页
Objective: To screen and analyze the differentially expressed genes between dilated cardiomyopathy (DCM) and chronic heart failure (CHF) based on bioinformatics methods. Methods: The Gene Expression Omnibus (GEO) data... Objective: To screen and analyze the differentially expressed genes between dilated cardiomyopathy (DCM) and chronic heart failure (CHF) based on bioinformatics methods. Methods: The Gene Expression Omnibus (GEO) database was used for data retrieval, and the chip data GSE3585 was downloaded, which was the original data of DCM and normal control group. At the same time, the chip data GSE76701 was downloaded, which was the original data of CHF and control group. Differentially expressed mRNAs (DEmRNAs) were screened by R language limma package, the data were standardized, and the common differentially expressed genes were screened. GO function and KEGG pathway enrichment analysis were performed on the common differentially expressed genes. String11.0 online tool was used for data analysis to obtain differentially expressed genes, and the results were imported into Cytoscape 3.9.1 software. The results were imported into Cytoscape 3.9.1 software, and the common expression gene module was obtained by MOCDE algorithm. Nine Hub genes were obtained by 10 algorithms such as MCC. Results: A total of 248 differentially expressed genes were screened. GO analysis showed that differentially expressed genes were mainly concentrated in 9 different physiological and pathological processes. KEGG analysis showed that the main signaling pathways involved in differentially expressed genes were 2, and 9 key differentially expressed genes were predicted: NPPB, NPPA, MYH6, FRZB, ASPN, SFRP4, RPS4Y1, DDX3Y. Conclusion: This study preliminarily explored the molecular mechanism of DCM and CHF, and obtained the common differentially expressed genes of the two diseases. Further experimental studies are needed to verify the correlation between gene expression and clinicopathological features. Provide new ideas for clinical drug treatment research. 展开更多
关键词 dilated Cardiomyopathy Chronic Heart Failure Bioinformatics Analysis Differentially Expressed Genes
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The Space Dilation: Analyzing Progressive Speed Reduction and Its Relativistic Parallels
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作者 Kreshnik Feka 《Journal of Applied Mathematics and Physics》 2024年第8期2990-3005,共16页
This paper presents a conceptual exploration that draws an intriguing parallelbetween a hypothetical travel scenario and the principles of special relativity. The scenario involves a traveler who reduces their speed b... This paper presents a conceptual exploration that draws an intriguing parallelbetween a hypothetical travel scenario and the principles of special relativity. The scenario involves a traveler who reduces their speed by an amount proportional to the distance traveled. Despite initially traveling at a high speed towards a given destination, the continual reduction in speed results in an asymptotic approach to the goal, analogous to the unattainable speed of light in relativity. Mathematically, the scenario is expressed through the Harmonic Series, demonstrating that the total travel time increases without bound, making the destination theoretically unreachable within a finite timeframe. This exploration mirrors the relativistic velocity addition and time dilation effects, providing a compelling analogy for understanding asymptotic limits. By highlighting the profound implications of diminishing returns and unattainable goals, this paper aims to stimulate further discussion and exploration of these fascinating parallels. 展开更多
关键词 Asymptotic Limits Special Relativity Harmonic Series Time dilation Diminishing Returns
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Time Dilation Cosmology 2
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第4期448-461,共14页
This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conu... This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conundrums in astrophysics, and ties astrophysics directly to quantum physics. It begins with a brief summary of the TDC model and contains the new derivation for the time dilation version of the formula for summing relativistic velocities, Einstein’s gravitational constant and the time dilation versions for the Lorentz factor and the Euclidean norm of the 3d velocity vector, the two of which can then be used in the Four-velocity formula. It is demonstrated how orbital curvature is manifested as the resultant of two time dilation-manifested velocities. It also explains why an interferometer cannot distinguish free fall from zero gravity and further elaborates on the author’s previous explanations of how spiral galaxies are formed, and contains mathematical proof that Black Holes are actually Magnetospheric Eternally Collapsing Objects (MECOs) that are massless spacetime vortices. 展开更多
关键词 GRAVITATION Time Time dilation Celestial Mechanics ISM: Kinematics and Dynamics Cosmology: Theory Galaxies: Evolution
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Construction of A Prediction Model for Atrial Fibrillation in Patients with Dilated Cardiomyopathy and Heart Failure
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作者 Kaizheng Liu Chengjie Liu 《Journal of Clinical and Nursing Research》 2024年第1期228-232,共5页
Dilated cardiomyopathy(DCM)is a common myocardial disease characterized by enlargement of the heart cavity and decreased systolic function,often leading to heart failure(HF)and arrhythmia.The occurrence of atrial fibr... Dilated cardiomyopathy(DCM)is a common myocardial disease characterized by enlargement of the heart cavity and decreased systolic function,often leading to heart failure(HF)and arrhythmia.The occurrence of atrial fibrillation(AF)is closely related to the progression and prognosis of the disease.In recent years,with the advancement of medical imaging and biomarkers,models for predicting the occurrence of AF in DCM patients have gradually become a research hotspot.This article aims to review the current situation of AF in DCM patients and explore the importance and possible methods of constructing predictive models to provide reference for clinical prevention and treatment.We comprehensively analyzed the risk factors for AF in DCM patients from epidemiological data,pathophysiological mechanisms,clinical and laboratory indicators,electrocardiogram and imaging parameters,and biomarkers,and evaluated the effectiveness of existing predictive models.Through analysis of existing literature and research,this article proposes a predictive model that integrates multiple parameters to improve the accuracy of predicting AF in DCM patients and provide a scientific basis for personalized treatment. 展开更多
关键词 dilated cardiomyopathy Heart failure Atrial fibrillation Prediction model
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Meta-analysis comparison of endoscopic papillary balloon dilatation and endoscopic sphincteropapillotomy 被引量:28
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作者 Hong-Chuan Zhao Liang He +2 位作者 Da-Chen Zhou Xiao-Ping Geng Fa-Ming Pan 《World Journal of Gastroenterology》 SCIE CAS 2013年第24期3883-3891,共9页
AIM: To assess endoscopic papillary balloon dilatation (EPBD) and endoscopic sphincteropapillotomy (EST) for common bile duct (CBD) stone removal using a meta-analysis. METHODS: Randomized controlled trials published ... AIM: To assess endoscopic papillary balloon dilatation (EPBD) and endoscopic sphincteropapillotomy (EST) for common bile duct (CBD) stone removal using a meta-analysis. METHODS: Randomized controlled trials published from 1990 to 2012 comparing EPBD with EST for CBD stone removal were evaluated. This meta-analysis was performed to estimate short-term and long-term com-plications of these two treatments. The fixed random effect model or random effect model was established to analysis the data. Results were obtained by analyz-ing the relative risk, odds ratio, and 95%CI for a given comparison using RevMan 5.1. Statistical significance was defined asP < 0.05. Risk of bias was evaluated us-ing a funnel plot. RESULTS: Of the 1975 patients analyzed, 980 of them were treated with EPBD and 995 were treated with EST. Of the patient population, patients in the EPBDgroup were younger (OR=-1.16, 95%CI:-1.49 to 0.84, P<0.01). There were no significant differences in gender proportion, average size of stones, number of gallstones, previous cholecystectomy, the incidence of duodenal diverticulum, CBD diameter or the total follow-up time between EST and EPBD groups. Com-pared with EST, the total stone clearance in the EPBD group decreased (OR=0.64, 95%CI: 0.42 to 0.96,P=0.03), the use of stone extraction baskets significantly increased (OR=1.91, 95%CI: 1.41 to 2.59, P<0.01), and the incidence of pancreatitis significantly increased (OR=2.79, 95%CI: 1.74 to 4.45, P<0.0001). The incidence of bleeding (OR=0.12, 95%CI: 0.04 to 0.34, P<0.01) and cholecystitis (OR=0.41, 95%CI: 0.20 to 0.84, P=0.02) significantly decreased. The stone re-currence rate also was significantly reduced in EPBD (OR=0.48, 95%CI: 0.26 to 0.90, P=0.02). There were no significant differences between the two groups with the incidence of stone removal at first attempt, hours of operation, total short-term complications and infection, perforation, or acute cholangitis. CONCLUSION: Although the incidence of pancreatitis was higher, the overall stone clearance rate and risk of bleeding was lower with EPBD compared to EST. 展开更多
关键词 Common BILE duct stone ENDOSCOPIC papil-lary BALLOON dilatation ENDOSCOPIC sphincteropapilloto-my META-ANALYSIS
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Is endoscopic papillary balloon dilatation really a risk factor for post-ERCP pancreatitis? 被引量:24
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作者 Toshio Fujisawa Koichi Kagawa +3 位作者 Kantaro Hisatomi Kensuke Kubota Atsushi Nakajima Nobuyuki Matsuhashi 《World Journal of Gastroenterology》 SCIE CAS 2016年第26期5909-5916,共8页
Endoscopic papillary balloon dilatation(EPBD) is useful for decreasing early complications of endoscopic retrograde cholangio-pancreatography(ERCP), including bleeding, biliary infection, and perforation, but it is ge... Endoscopic papillary balloon dilatation(EPBD) is useful for decreasing early complications of endoscopic retrograde cholangio-pancreatography(ERCP), including bleeding, biliary infection, and perforation, but it is generally avoided in Western countries because of a relatively high reported incidence of post-ERCP pancreatitis(PEP). However, as the efficacy of endoscopic papillary largeballoon dilatation(EPLBD) becomes widely recognized, EPBD is attracting attention. Here we investigate whether EPBD is truly a risk factor for PEP, and seek safer and more effective EPBD procedures by reviewing past studies. We reviewed thirteen randomised control trials comparing EPBD and endoscopic sphincterotomy(EST) and ten studies comparing direct EPLBD and EST. Three randomized controlled trials of EPBD showed significantly higher incidence of PEP than EST, but no study of EPLBD did. Careful analysis of these studies suggested that longer and higher-pressure inflation of balloons might decrease PEP incidence. The paradoxical result that EPBD with small-calibre balloons increases PEP incidence while EPLBD does not may be due to insufficient papillary dilatation in the former. Insufficient dilatation could cause the high incidence of PEP through the use of mechanical lithotripsy and stress on the papilla at the time of stone removal. Sufficient dilation of the papilla may be useful in preventing PEP. 展开更多
关键词 Endoscopic papillary balloon dilatation Post-endoscopic retrograde cholangio-pancreatography pancreatitis Endoscopic papillary large-balloon dilatation Endoscopic sphincterotomy Randomized controlled trial
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Nasobiliary drainage after endoscopic papillary balloon dilatation may prevent postoperative pancreatitis 被引量:18
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作者 Xiao-Dan Xu Jian-Jun Dai +1 位作者 Jian-Qing Qian Wei-Jun Wang 《World Journal of Gastroenterology》 SCIE CAS 2015年第8期2443-2449,共7页
AIM:To evaluate the necessity of endoscopic nasobiliary drainage(ENBD)catheter placement after clearance of common bile duct(CBD)stones.METHODS:Patients enrolled in this study were randomly divided into two groups,acc... AIM:To evaluate the necessity of endoscopic nasobiliary drainage(ENBD)catheter placement after clearance of common bile duct(CBD)stones.METHODS:Patients enrolled in this study were randomly divided into two groups,according to whether or not they received ENBD after the removal of CBD stones.Group 1(ENBD group)was then subdividedinto three groups:G1a patients received an endoscopic papillary balloon dilatation(EPBD),G1b patients received an endoscopic sphincterotomy(EST),and G1c patients received neither.Group 2(non-ENBD group)patients were also subdivided into three groups(G2a,G2b,and G2c),similar to Group 1.The maximum CBD diameter,the time for C-reactive protein(CRP)to normalize,levels of serum amylase,total serum bilirubin(TB)and alanine aminotransferase(ALT),and postoperative hospitalization duration(PHD)were measured.RESULTS:A total of 218 patients(139 males,79females),with an average age of 60.1±10.8 years,were enrolled in this study.One hundred and thirteen patients who received ENBD were included in Group 1,and 105patients who did not receive ENBD were included in Group 2.The baseline clinical characteristics were similar in both groups.There were no significant differences in post-endoscopic retrograde cholangiopancreatography(ERCP)-related complications when Groups 1 and 2 were compared.Seventy-seven patients underwent EPBD,and41 received an ENBD tube(G1a)and 36 did not(G2a).Seventy-three patients underwent EST,and 34 patients received an ENBD tube(G1b)and 39 did not(G2b).The remaining 68 patients underwent neither EPBD nor EST;of these patients,38 received an ENBD tube(G1c)and 30 did not(G2c).For each of the three pairs of subgroups(G1a vs G2a,G1b vs G2b,G1c vs G2c),there were no significant differences detected in the PHD or the time to normalization of CRP,TB and ALT.In the EPBD group,the incidence of post-ERCP pancreatitis,hyperamylasemia and overall patient complications was significantly higher for G2a(post-ERCP pancreatitis:6/36vs 0/41,P=0.0217;hyperamylasemia:11/36 vs 4/41,P=0.0215;overall patient complications:18/36 vs 7/41,P=0.0029).CONCLUSION:After successful CBD stone clearance,ENBD is only beneficial when an EPBD procedure hasbeen performed. 展开更多
关键词 ENDOSCOPIC PAPILLARY BALLOON dilatation ENDOSCOPIC
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Long-term results of graded pneumatic dilatation under endoscopic guidance in patients with primary esophageal achalasia 被引量:11
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作者 AhmetDobrucali YusufErzin +1 位作者 MuratTuncer AhmetDirican 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第22期3322-3327,共6页
AIM:Achalasia is the best known primary motor disorder of the esophagus in which the lower esophageal sphincter (LES)has abnormally high resting pressure and incomplete relaxation with swallowing.Pneumatic dilatation ... AIM:Achalasia is the best known primary motor disorder of the esophagus in which the lower esophageal sphincter (LES)has abnormally high resting pressure and incomplete relaxation with swallowing.Pneumatic dilatation remains the first choice of treatment.The aims of this study were to determine the long term clinical outcome of treating achatasia initially with pneumatic dilatation and usefulness of pneumatic dilatation technique under endoscopic observation without fluoroscopy. METHODS:A total of 65 dilatations were performed in 43 patients with achalasia[23 males and 20 females,the mean age was 43 years(range,19-73)].All patients underwent an initial dilatation by inflating a 30 mm balloon to 15 psi under endoscopic control.The need for subsequent dilatation was based on symptom assessment.A 3.5 cm balloon was used for repeat procedures. RESULTS:The 30 mm balloon achieved a satisfactory result in 24 patients(54%)and the 35 mm ballon in 78% of the remainder(14/18).Esophageal perforation as a short-term complication was observed in one patient(2.3%).The only late complication encountered was gastroesophageal reflux in 2(4%)patients with a good response to dilatation.The mean follow-up period was 2.4 years(6 mo-5 years).Of the patients studied,38(88%)were relieved of their symptoms after only one or two sessions.Five patients were referred for surgery(one for esophageal perforation and four for persistent or recurrent symptoms).Among the patients whose follow up information was available,the percentage of patients in remission was 79%(19/24)at 1 year and 54%(7/13)at 5 years. CONCLUSION:Performing balloon dilatation under endoscopic observation as an outpatient procedure is simple,safe and efficacious for treating patients with achalasia and referral of surgical myotomy should be considered for patients who do not respond to medical therapy or individuals that do not desire pneumatic dilatations. 展开更多
关键词 Adult Aged Balloon dilatation Endoscopy Gastrointestinal Esophageal Achalasia Female Follow-Up Studies Humans Male MANOMETRY Middle Aged OUTPATIENTS Treatment Outcome
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