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Cell Research 1997年第2期7卷 179-193页

作者： vivia ct liang TIFFANY SEDGWICK YUN BOSHI(Laboratory of Molecular Embryology NICHD/NIH, Bldg.18T, Rm. 106 Bethesda, MD 20892-5431 USA) Laboratory of Molecular Embryology NICHD/NIH Bldg. 18T Rm. 106 Bethesda MD 20892-5431 USA

The complex transformation of a tadpole to a frogduring amphibian development is under the control of thyroid hormone (T3). T3 is known to regulate gene transcription through its nuclear receptors. We have previouslyisolated many genes which are up-regulated by T3 in theintestine of Xenopus laevis tadpoles. We have now cloneda full- length cDNA for one such gene (IU12). Sequenceanalysis shows that the IU12 cDNA encodes a plasmamembrane protein with 12 transmembrane domains andhomologous to a mammalian gene associated with cell activation and organ development. Similarly, we have foundthat IU12 is activated during intestinal remodeling whenboth cell death and proliferation take place. Furthermore,IU12 is an early T3-response gene and its expression in theintestine during T3-induced metamorphosis mimics thatduring normal development. These results argue for a roleof IU12 in the signal transduction pathways leading to intestinal metamorphosis.

关键词： Thyroid hormone Xenopus laevis cell proliferation organogenesis transcription factor

Time-domain Differential Protection Based on Operating and Restraining Trajectory Indices for Lines Connecting Battery Storage Energy Stations

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1074-1086页

作者： Yingyu liang Cunyue Pan School of Mechanical and Electrical Engineering China University of Mining and Technology(Beijing)BeijingChina

Battery energy storage stations(BESSs)pose sever-al challenges for both phasor-based differential protection and the newly-proposed time-domain differential *** challenges include low sensitivity and even ***,the negative impact of various nonideal conditions,including current transformer(ct)saturation,errors,and outliers,on the security of differential protection remains an important *** by the aforementioned issues,this study ac-counts for the trajectory distribution discrepancy on Cartesian plane under various conditions and proposes a time-domain dif-ferential protection *** this paper,the trajectory formed by operating and restraining current samples is ***,after considering different operating states,the fault severity levels,and nonideal conditions,the variances in trajectory distribution between internal and external faults are extensively *** this basis,the Cartesian plane is divided into operating,uncertainty,and restraining ***-ther,the operating and restraining trajectory indices are meticu-lously designed and a protection criterion based on these indi-ces is formed to accurately separate internal faults from other events,unaffected by ct saturation,errors,and *** exceptional performance of the proposed protection method is extensively validated through PSCAD simulations and a hard-ware-in-the-loop testing *** the dependability,sensitivity,and security,the proposed protection method outper-forms three state-of-the-art differential protection methods.

关键词： Battery energy storage station time-domain differential protection operating trajectory index(OTI) restraining trajectory index(RTI)

Three-dimensional finite element simulation and reconstruction of jointed rock models using ct scanning and photogrammetry

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1348-1361页

作者： Yingxian Lang Zhengzhao liang Zhuo Dong State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian116024China School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo454003China

The geometry of joints has a significant influence on the mechanical properties of *** simplify the curved joint shapes in rocks,the joint shape is usually treated as straight lines or planes in most laboratory experiments and numerical *** this study,the computerized tomography (ct) scanning and photogrammetry were employed to obtain the internal and surface joint structures of a limestone sample,*** describe the joint geometry,the edge detection algorithms and a three-dimensional (3D) matrix mapping method were applied to reconstruct ct-based and photogrammetry-based jointed rock *** comparison tests,the numerical uniaxial compression tests were conducted on an intact rock sample and a sample with a joint simplified to a plane using the parallel computing *** results indicate that the mechanical characteristics and failure process of jointed rocks are significantly affected by the geometry of *** presence of joints reduces the uniaxial compressive strength (UCS),elastic modulus,and released acoustic emission (AE) energy of rocks by 37%–67%,21%–24%,and 52%–90%,*** to the simplified joint sample,the proposed photogrammetry-based numerical model makes the most of the limited geometry information of *** UCS,accumulative released AE energy,and elastic modulus of the photogrammetry-based sample were found to be very close to those of the ct-based *** UCS value of the simplified joint sample (i.e.38.5 MPa) is much lower than that of the ct-based sample (i.e.72.3 MPa).Additionally,the accumulative released AE energy observed in the simplified joint sample is 3.899 times lower than that observed in the ct-based *** scanning provides a reliable means to visualize the joints in rocks,which can be used to verify the reliability of photogrammetry *** application of the photogrammetry-based sample enables detailed analysis for estimating the mechanical properties of jointed rocks.

关键词： X-ray computerized tomography(ct)scanning Photogrammetry Parallel computing Numerical simulation Uniaxial compression test Digital image processing

Neuronal conversion from glia to replenish the lost neurons

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Neural Regeneration Research 2024年第7期19卷 1446-1453页

作者： Shiyu liang Jing Zhou Xiaolin Yu Shuai Lu Ruitian Liu National Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijingChina School of Chemical Engineering University of Chinese Academy of SciencesBeijingChina Department of Geriatric Rehabilitation Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal *** rtunately,the neurons of most mammals including humans do not possess the ability to *** of lost neurons becomes an appealing therapeutic strategy to reve rse the disease *** of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain *** of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell *** far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous ***,some recent papers did not obtain expected results,and discrepancies ***,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future *** also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies.

关键词： astrocytes neural stem cells neurodegenerative diseases neuron polypyrimidine tract binding protein 1 repair reprogramming small molecule transcription factor transdifferentiation

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Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2773-2806页

作者： Long Chen Ting Li liang Liu Wenshuo Wang Xiaoxiao Du Wei Wang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Cardiac Surgery Zhongshan HospitalFudan UniversityShanghai200093China School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China

This study explores the implementation of computed tomography(ct)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)*** order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active *** mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are *** these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the *** study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromct images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures.

关键词： Calcified aortic valves tensile test constitutive relations ct reconstruction isogeometric hyperelastic analysis

Colorectal Cancer Segmentation Algorithm Based on Deep Features from Enhanced ct Images

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Computers, Materials & Continua 2024年第8期80卷 2495-2510页

作者： Shi Qiu Hongbing Lu Jun Shu Ting liang Tao Zhou School of Biomedical Engineering Fourth Military Medical UniversityXi’an710119China Department of Radiology Xijing HospitalFourth Military Medical UniversityXi’an710032China Department of Radiology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710061China School of Computer Science and Engineering North Minzu UniversityYinchuan750030China

Colorectal cancer,a malignant lesion of the intestines,significantly affects human health and life,emphasizing the necessity of early detection and *** segmentation of colorectal cancer regions directly impacts subsequent staging,treatment methods,and prognostic *** colonoscopy is an effective method for detecting colorectal cancer,its data collection approach can cause patient *** address this,current research utilizes Computed Tomography(ct)imaging;however,conventional ct images only capture transient states,lacking sufficient representational capability to precisely locate colorectal *** study utilizes enhanced ct images,constructing a deep feature network from the arterial,portal venous,and delay phases to simulate the physician’s diagnostic process and achieve accurate cancer *** innovations include:1)Utilizing portal venous phase ct images to introduce a context-aware multi-scale aggregation module for preliminary shape extraction of colorectal cancer.2)Building an image sequence based on arterial and delay phases,transforming the cancer segmentation issue into an anomaly detection problem,establishing a pixel-pairing strategy,and proposing a colorectal cancer segmentation algorithm using a Siamese *** with 84 clinical cases of colorectal cancer enhanced ct data demonstrated an Area Overlap Measure of 0.90,significantly better than Fully Convolutional Networks(FCNs)at *** research will explore the relationship between conventional and enhanced ct to further reduce segmentation time and improve accuracy.

关键词： Colorectal cancer enhanced ct multi-scale siamese network segmentation

Energy spectrum computed tomography multi-parameter imaging in preoperative assessment of vascular and neuroinvasive status in gastric cancer

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2511-2520页

作者： Jing Wang Jian-Cheng liang Fa-Te Lin Jun Ma Department of Radiology Pingluo County People's HospitalShizuishan 753400Ningxia Hui Autonomous RegionChina Department of Gastrointestinal Surgery Jiangsu Provincial People's HospitalNanjing 210029Jiangsu ProvinceChina

BACKGROUND Vascular and nerve infiltration are important indicators for the progression and prognosis of gastric cancer(GC),but traditional imaging methods have some limitations in preoperative *** recent years,energy spectrum computed tomography(ct)multiparameter imaging technology has been gradually applied in clinical practice because of its advantages in tissue contrast and lesion detail *** To explore and analyze the value of multiparameter energy spectrum ct imaging in the preoperative assessment of vascular invasion(LVI)and nerve invasion(PNI)in GC *** Data from 62 patients with GC confirmed by pathology and accompanied by energy spectrum ct scanning at our hospital between September 2022 and September 2023,including 46 males and 16 females aged 36-71(57.5±9.1)years,were retrospectively *** patients were divided into a positive group(42 patients)and a negative group(20 patients)according to the presence of LVI/*** ct values(ct40 keV,ct70 keV),iodine concentration(IC),and normalized IC(NIC)of lesions in the upper energy spectrum ct images of the arterial phase,venous phase,and delayed phase 40 and 70 keV were measured,and the slopes of the energy spectrum curves[K(40-70)]from 40 to 70 keV were *** Core Tip:To investigate the application value of multiparameter energy spectrum computed tomography(ct)imaging in the preoperative assessment of vascular and nerve infiltration in patients with gastric cancer(GC).The imaging data of GC patients were retrospectively analyzed to evaluate the accuracy and sensitivity of ct for identifying and quantifying vascular and nerve infiltration and for comparison with postoperative pathological *** purpose of this study was to verify the clinical feasibility and potential advantages of multiparameter energy spectrum ct imaging in guiding preoperative diagnosis and treatment decision-making and to provide a new imaging basis for improving the diagnostic accuracy

关键词： Tomography X-ray computer Energy spectrum computed tomography Gastric cancer Vascular invasion Nerve invasion Cross-sectional study

A deep learning model based on contrast-enhanced computed tomography for differential diagnosis of gallbladder carcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 376-384页

作者： Fei Xiang Qing-Tao Meng Jing-Jing Deng Jie Wang Xiao-Yuan liang Xing-Yu Liu Sheng Yan Department of Hepatobiliary Pancreatic Surgery Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Radiology Affiliated Chuzhou First People’s HospitalAnhui Medical UniversityChuzhou 239000China

Background:Gallbladder carcinoma(GBC)is highly malignant,and its early diagnosis remains *** study aimed to develop a deep learning model based on contrast-enhanced computed tomography(ct)images to assist radiologists in identifying ***:We retrospectively enrolled 278 patients with gallbladder lesions(>10 mm)who underwent contrast-enhanced ct and cholecystectomy and divided them into the training(n=194)and validation(n=84)*** deep learning model was developed based on ResNet50 *** and clinical models were built based on support vector machine(SVM)*** comprehensively compared the performance of deep learning,radiomics,clinical models,and three ***:Three radiomics features including LoG_3.0 gray-level size zone matrix zone variance,HHL firstorder kurtosis,and LHL gray-level co-occurrence matrix dependence variance were significantly different between benign gallbladder lesions and GBC,and were selected for developing radiomics *** regression analysis revealed that age≥65 years[odds ratios(OR)=4.4,95%confidence interval(CI):2.1-9.1,P37 U/mL(OR=4.0,95%CI:1.6-10.0,P=0.003)were significant clinical risk factors of *** deep learning model achieved the area under the receiver operating characteristic curve(AUC)values of 0.864(95%CI:0.814-0.915)and 0.857(95%CI:0.773-0.942)in the training and validation datasets,which were comparable with radiomics,clinical models and three *** sensitivity of deep learning model was the highest both in the training[90%(95%CI:82%-96%)]and validation[85%(95%CI:68%-95%)]***:The deep learning model may be a useful tool for radiologists to distinguish between GBC and benign gallbladder lesions.

关键词： Gallbladder carcinoma Computed tomography Deep learning Radiomics

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Pleural empyema with endobronchial mass due to Rhodococcus equi infection after renal transplantation: A case report and review of literature

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World Journal of Clinical Cases 2024年第1期12卷 224-231页

作者： Guo-Fu liang Sheng Chao Zhou Sun Ke-Jing Zhu Qian Chen Lei Jia Yu-Lin Niu Department of Organ Transplantation School of Clinical MedicineGuizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina Department of Organ Transplantation The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina

BACKGROUND Kidney transplantation is the best option for patients with end-stage renal ***,the need for lifelong immunosuppression results in renal transplant recipients being susceptible to various *** equi(***)is a rare opportunistic pathogen in humans,and there are limited reports of infection with *** in post-renal transplant recipients and no uniform standard of *** article reports on the diagnosis and treatment of a renal transplant recipient infected with *** 21 mo postoperatively and summarizes the charac-teristics of infection with *** after renal transplantation,along with a detailed review of the ***,we present the case of a 25-year-old man who was infected with *** 21 mo after renal *** the clinical features at the time of presentation were not specific,chest computed tomography(ct)showed a large volume of pus in the right thoracic cavity and right middle lung atelectasis,and fiberoptic bronchoscopy showed an endobronchial mass in the right middle and lower lobe *** culture and metagenomic next-generation sequen-cing sequencing of the pus were suggestive of *** *** immunosup-pressive drugs were immediately suspended and intravenous vancomycin and azithromycin were administered,along with adequate drainage of the *** endobronchial mass was then *** the patient’s clinical symptoms and chest ct presentation resolved,he was switched to intravenous ciprofloxacin and azithromycin,followed by oral ciprofloxacin and *** patient was re-hospitalized 2 wk after discharge for recurrence of *** *** recovered after another round of adequate abscess drainage and intravenous ciprofloxacin and *** Infection with *** in renal transplant recipients is rare and complex,and the clinical presentation lacks *** antibiotic therapy is required,and adequate abscess drainage and s

关键词： Kidney transplantation Rhodococcus equi Pleural empyema Pulmonary atelectasis Immunosuppression Case report

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行胃袖状切除术病人食管裂孔疝的诊治策略

中国实用外科杂志 2024年第8期44卷 871-875页

作者：梁辉南京医科大学第一附属医院减重代谢外科江苏南京210029

肥胖病人合并胃食管反流病和食管裂孔疝的比例较高。胃袖状切除术(SG)后可能增加或者缓解反流症状,手术中同时处理合并的食管裂孔疝是减少术后反流的重要措施,同时要做到胃袖状切除术的标准化。术前评估预测是否合并食管裂孔疝有时是比... 详细信息

肥胖病人合并胃食管反流病和食管裂孔疝的比例较高。胃袖状切除术(SG)后可能增加或者缓解反流症状,手术中同时处理合并的食管裂孔疝是减少术后反流的重要措施,同时要做到胃袖状切除术的标准化。术前评估预测是否合并食管裂孔疝有时是比较困难的,术前胃食管反流病问卷、胃镜、上消化道造影、ct等可以提示术中是否需要进行探查。术中根据食管裂孔疝的解剖表现进行同期修补,根据需要决定是否使用补片。

关键词：减重代谢外科食管裂孔疝胃食管反流病胃袖状切除术 Roux-en-Y胃旁路术

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