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Application of CD34 expression combined with three-phase dynamic contrast-enhanced computed tomography scanning in preoperative staging of gastric cancer
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作者 Hua Liu Kang-Yan Zhao 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第11期2513-2524,共12页
BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and prognosis.Dynamic three-phase enhanced computed tomography(CT)scanning ... BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and prognosis.Dynamic three-phase enhanced computed tomography(CT)scanning for preoperative staging of GC has limitations in evaluating tumor angiogenesis.CD34,a marker on vascular endothelial cell surfaces,is promising in evaluating tumor angiogenesis.We explored the value of their combination for preoperative staging of GC to improve the efficacy and prognosis of patients with GC.Medical records of 106 patients with GC treated at the First People's Hospital of Lianyungang between February 2021 and January 2023 were retrospectively studied.All patients underwent three-phase dynamic contrast-enhanced CT scanning before surgery,and CD34 was detected in gastroscopic biopsy specimens.Using surgical and pathological results as the gold standard,the diagnostic results of three-phase dynamic contrast-enhanced CT scanning at different T and N stages were analyzed,and the expression of CD34-marked microvessel density(MVD)at different T and N stages was determined.The specificity and sensitivity of three-phase dynamic contrast-enhanced CT and CD34 in T and N staging were calculated;those of the combined diagnosis of the two were evaluated in parallel.Independent factors affecting lymph node metastasis were analyzed using multiple logistic regression.RESULTS The accuracy of three-phase dynamic contrast-enhanced CT scanning in diagnosing stages T1,T2,T3 and T4 were 68.00%,75.00%,79.41%,and 73.68%,respectively,and for diagnosing stages N0,N1,N2,and N3 were 75.68%,74.07%,85.00%,and 77.27%,respectively.CD34-marked MVD expression increased with increasing T and N stages.Specificity and sensitivity of three-phase dynamic contrast-enhanced CT in T staging were 86.79%and 88.68%;for N staging,89.06%and 92.86%;for CD34 in T staging,64.15%and 88.68%;and for CD34 in N staging,84.38%and 78.57%,respectively.Specificity and sensitivity of joint diagnosis in T staging were 55.68%and 98.72%,and N staging were 75.15%and 98.47%,respectively,with the area under the curve for diagnosis improving accordingly.According to multivariate analysis,a longer tumor diameter,higher pathological T stage,lower differ-entiation degree,and higher expression of CD34-marked MVD were independent risk factors for lymph node metastasis in patients with GC.CONCLUSION With high accuracy in preoperatively determining the invasion depth and lymph node metastasis of GC,CD34 expression and three-phase dynamic contrast-enhanced CT can provide a reliable basis for surgical resection. 展开更多
关键词 CD34 Three-phase dynamic contrast-enhanced computed tomography scanning Gastric cancer Preoperative staging INVASION Lymph node metastasis
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Endodontic management of a fused left maxillary second molar and two paramolars using cone beam computed tomography: A case report 被引量:1
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作者 Xiao-Han Mei Jin Liu +6 位作者 Wei Wang Qian-Xia Zhang Tao Hong Shi-Zhu Bai Xiao-Gang Cheng Yu Tian Wen-Kai Jiang 《World Journal of Clinical Cases》 SCIE 2022年第23期8367-8374,共8页
BACKGROUND Fused teeth usually involve several complications,such as the development of caries in the groove between fused crowns,tooth impaction,diastemas,aesthetic and periodontal problems,and pulpal pathosis,due to... BACKGROUND Fused teeth usually involve several complications,such as the development of caries in the groove between fused crowns,tooth impaction,diastemas,aesthetic and periodontal problems,and pulpal pathosis,due to the complex anatomical structure of fused teeth.A thorough diagnosis is paramount to forming an accurate treatment plan and obtaining a favourable prognosis.With the advent of cone-beam computed tomography(CBCT),accurate 3-dimensional images of teeth and their surrounding dentoalveolar structures can now be readily obtained,and the technology can accurately provide a minimally invasive approach to acquire detailed diagnostic information.Therefore,we utilize CBCT data herein to generate a digital model for the infected region in a patient,and this model enables us to better plan the management of his case.CASE SUMMARY This report details the diagnosis and endodontic treatment of a rare case involving a fused maxillary second molar and two paramolars with apical periodontitis.The patient experienced pain upon biting and cold sensitivity in the area of the maxillary left molar.No caries or other defects were identified in these teeth,and a normal response to a pulp electric viability test was observed.With the aid of CBCT and digital model technology,we initially suspected that the infection originated from the isthmus between the maxillary second molar and two paramolars.Therefore,we only treated the isthmus by an endodontic approach and did not destroy the original tooth structure;furthermore,the vital pulp was retained,and good treatment outcomes were observed at the 24-month follow-up.CONCLUSION This finding may provide new insights and perspectives on the diagnosis and treatment of fused teeth. 展开更多
关键词 Cone-beam computed tomography scans Endodontic therapy Fusion of teeth Maxillary molar Digital model technology Case report
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Advantages of preoperative planning using computed tomography scan for treatment of malleolar ankle fractures 被引量:1
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作者 Luigi Tarallo Gian Mario Micheloni +3 位作者 Michele Mazzi Arturo Rebeccato Michele Novi Fabio Catani 《World Journal of Orthopedics》 2021年第3期129-139,共11页
Malleolar ankle fractures have been classified using plain radiographs,and there is no consensus regarding the role of computed tomography(CT)scans in preoperative planning.We analyzed critical aspects,such as limits ... Malleolar ankle fractures have been classified using plain radiographs,and there is no consensus regarding the role of computed tomography(CT)scans in preoperative planning.We analyzed critical aspects,such as limits of standard radiographs,types of injury,classification methods and cost/benefit evaluations.CT scans allow a 3 D analysis of the fracture to be obtained and consequently assess the indication for surgical procedure,surgical access and the type of fixation devices required.This exam is useful for detecting lesions that may go unnoticed on radiographs and will help surgeons to clarify the pathoanatomy of ankle fractures.According to Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association(AO/OTA)classification,CT scan is recommended in medial malleolar fractures with vertical rim,type 44 B fractures with posterior malleolar involvement and all type 44 C fractures(according to AO/OTA).Also Tillaux-Chaput fractures(43-B1 according to AO/OTA),malleolar fractures in the presence of distal tibial fractures(43 according to AO/OTA)and distal tibia fractures in adolescents should be studied with CT scans. 展开更多
关键词 computed tomography scan Malleolar fractures PLANNING TRAUMA IMAGING
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Preoperative [18]fluorodeoxyglucose-positron emission tomography/computed tomography in early stage breast cancer: Rates of distant metastases
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作者 Vincent Vinh-Hung Hendrik Everaert +8 位作者 Karim Farid Navid Djassemi Jacqueline Baudin-Veronique Stefanos Bougas Yuriy Michailovich Clarisse Joachim-Contaret Elsa Cécilia-Joseph Claire Verschraegen Nam P Nguyen 《World Journal of Radiology》 CAS 2017年第7期312-320,共9页
AIM To investigate rates of distant metastases(DM) detected with [18]fluorodeoxyglucose-positron emissiontomography/computed tomography(^(18)FDG-PET/CT) in early stage invasive breast cancer.METHODS We searched the En... AIM To investigate rates of distant metastases(DM) detected with [18]fluorodeoxyglucose-positron emissiontomography/computed tomography(^(18)FDG-PET/CT) in early stage invasive breast cancer.METHODS We searched the English language literature databases of PubM ed, EMBASE, ISI Web of Knowledge, Web of Science and Google Scholar, for publications on DM detected in patients who had ^(18)FDG-PET/CT scans as part of the staging for early stages of breast cancer(stage Ⅰ?and Ⅱ), prior to or immediately following surgery. Reports published between 2011 and 2017 were considered. The systematic review was conducted according to the PRISMA guidelines.RESULTS Among the 18 total studies included in the analysis, the risk of DM ranged from 0% to 8.3% and 0% to 12.9% for stage Ⅰ?and Ⅱ invasive breast cancer, respectively. Among the patients with clinical stage Ⅱ, the rate of occult metastases diagnosed by ^(18)FDG-PET/CT was 7.2%(range, 0%-19.6%) for stage ⅡA and 15.8%(range, 0%-40.8%) for stage ⅡB. In young patients(< 40-yearold), ^(18)FDG-PET/CT demonstrated a higher prevalence of DM at the time of diagnosis for those with aggressive histology(i.e., triple-negative receptors and poorly differentiated grade).CONCLUSION Young patients with poorly differentiated tumors and stage ⅡB triple-negative breast cancer may benefit from ^(18)FDG-PET/CT at initial staging to detect occult DM prior to surgery. 展开更多
关键词 Breast cancer Early stage Staging workup Distant metastases fluorodeoxyglucose-positron emission tomography/computed tomography scan
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Development of Segmentation and Classification Algorithms for Computed Tomography Images of Human Kidney Stone
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作者 Orobosa L.Joseph Waliu O.Apena 《Journal of Electronic Research and Application》 2021年第5期1-10,共10页
Computed tomography(CT)scan diagnostics procedures adopt the use of image infbnnation retrieval system with the help of radiographer's expertise.However,this technique is prone to errors,Significant height of accu... Computed tomography(CT)scan diagnostics procedures adopt the use of image infbnnation retrieval system with the help of radiographer's expertise.However,this technique is prone to errors,Significant height of accuracy is required in healthcare decision support,as 20%of CT scans are associated with error.The application of artificial intelligence(Al)can improve performance level,mitigate human error,and enhance clinical decision support in the context of time and accuracy.The study introduced machine learning algorithm to analyze stream of anonymous CT scans of kidney.The research adopted deep learning approach for segmentation and classification of kidney stone(renal calculi)images in Python(with Keras and TensorFlow)environment.A control volume of data along with 336 kidney stone images were used to train the deep learning network with 10 testing images.The training images were divided into two sets(folders)as follows;one was labeled as STONE(containing 167 images)and the other as NO-STONE(containing 169 images);10 iterations were performed for model training.The network layers were structured as input layer in the following with 2-D convolutional neural network machine learning(CNN-ML),ReLU activation,Maxpooling,and fully connected(dense)layer including the sigmoid activation layer.The training adopted a batch size of 8 with 10%validation.The output result,upon testing the model,has an accuracy of 90%,sensitivity value of 80%and effectiveness of 89%.The segmentation and classification algorithm model could be embedded in future CT diagnostic procedure to enhance medical decision support and accuracy. 展开更多
关键词 computed tomography scan DIAGNOSTICS Convolutional neural network ACCURACY Kidney Stone
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Conception the Fluid Flow Behavior within Oil Reservoir Rock by Using Computed Tomography(CT)Scan
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作者 Amani J.Majeed Falah A Abood Ahmed K.Alshara 《Journal of Mechanical Engineering Research》 2021年第2期11-20,共10页
The behavior of fluid flow has been studied during the different flow media over the past decades.In addition,the behavior of the flow of fluid through porous media has garnered much research interest.This paper sheds... The behavior of fluid flow has been studied during the different flow media over the past decades.In addition,the behavior of the flow of fluid through porous media has garnered much research interest.This paper sheds light on fissured rocks of oil reservoir media(as one of the porous media domain),and the effect of these fissured on fluid flow.In this article,the Finite Volume Method(FVM)has been used to visualize the behavior of single-phase fluid flow in an actual core according to the dual-porosity dual permeability model.The study was conducted in two parts,the first was the image processing for one of the real oil reservoir fractured rock images,where the image was processed and simulated by ANSYS-CFX software,and the results showed a complete visualizing of the fluid behavior during this domain.As for the other side,a simulation of a real reservoir rock belonging to the Al-Nour field in Iraq/Misan was made.The X-ray Computed Tomography(CT)scan has been used to convert the real fractured core to a dynamic domain.ANSYS-CFX program has been used and the results illustrated the pressure counter,the velocity counter,the velocity streamline,and the velocity vectors for the studied model in three dimensions.A comparison was made between the productivity index for fractured and non-fractured rock and the results explained that the presence of fracture can improve the productivity index to about 5.74%. 展开更多
关键词 computed tomography(CT)scan Al-Nour field Fluid flow
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Damage degradation mechanism and macro-meso structural response of mudstone after water wetting
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作者 SHAO Zhixin SONG Yanqi +3 位作者 ZHENG Junjie SHEN Fuxin LIU Chuanpeng YANG Juntao 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2825-2843,共19页
The predominant presence of weak interlayers primarily composed of mudstone renders them highly susceptible to a reduction in bearing capacity due to the water-rock weakening effect,significantly impacting the safety ... The predominant presence of weak interlayers primarily composed of mudstone renders them highly susceptible to a reduction in bearing capacity due to the water-rock weakening effect,significantly impacting the safety of open-pit mining operations.This study focuses on the weak mudstone layers within open-pit mine slopes.The mineral composition of mudstone and the microstructure evolution characteristics before and after water wetting were analyzed by X-ray diffraction(XRD)and scanning electron microscope(SEM).The meso-structure and parameter variation characteristics of mudstone interior space after water-rock interaction were quantified by computed tomography scanning test,and the damage variable characterization method was proposed.Additionally,according to the uniaxial compression test,the degradation characteristics of the macroscopic mechanical behavior of mudstone under different water wetting time were explored,and the elastic modulus and strength attenuation model of mudstone based on mesoscopic damage were established.Finally,building upon the macro-meso structural response characteristics of mudstone,an exploration of the failure characteristics and deterioration mechanism under the influence of water-rock interactions was undertaken.The results show that the water-rock interaction makes the internal defects of mudstone gradually develop and form a fracture network structure,which eventually leads to the deterioration of its macroscopic mechanical properties.The porosity,fractal dimension and damage characteristics of mudstone show an exponential trend with the increase of water wetting time.Moreover,the deterioration mechanism of mudstone after water wetting are postulated to encompass factors such as the hydrophilicity of mineral molecular structures,hydration stress and expansion effects on clay particles,as well as the spatial distribution of microcracks and the phenomenon of fracture adsorption.The outcomes of this research endeavor aim to provide certain reference value for further understanding the water-rock interaction and stability control of mudstone slope. 展开更多
关键词 Moisture absorption of mudstone computed tomography scanning test Fracture structure evolution Macro-meso structural response Deterioration mechanism
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Oil Production Optimization by Means of a Combined“Plugging,Profile Control,and Flooding”Treatment:Analysis of Results Obtained Using Computer Tomography and Nuclear Magnetic Resonance 被引量:1
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作者 Yanyue Li Changlong Liu +5 位作者 Wenbo Bao Baoqing Xue Peng Lv Nan Wang Hui Li Wenguo Ma 《Fluid Dynamics & Materials Processing》 EI 2022年第3期737-749,共13页
Due to long-term water injection,often oilfields enter the so-called medium and high water cut stage,and it is difficult to achieve good oil recovery and water reduction through standard methods(single profile control... Due to long-term water injection,often oilfields enter the so-called medium and high water cut stage,and it is difficult to achieve good oil recovery and water reduction through standard methods(single profile control and flooding measures).Therefore,in this study,a novel method based on“plugging,profile control,and flooding”being implemented at the same time is proposed.To assess the performances of this approach,physical simulations,computer tomography,and nuclear magnetic resonance are used.The results show that the combination of a gel plugging agent,a polymer microsphere flooding agent,and a high-efficiency oil displacement agent leads to better results in terms of oil recovery with respect to the situation in which these approaches are used separately(the oil recovery is increased by 15.37%).Computer tomography scan results show that with the combined approach,a larger sweep volume and higher oil washing efficiency are obtained.The remaining oil in the cluster form can be recovered in the middle and low permeability layer,increasing the proportion of the columnar and blind end states of the oil.The nuclear magnetic resonance test results show that the combined“plugging,profile control,and flooding”treatment can also be used to control more effectively the dominant channels of the high permeability layer and further expand the recovery degree of the remaining oil in the pores of different sizes in the middle and low permeability layers.However,for the low permeability layer(permeability difference of 20),the benefits in terms of oil recovery are limited. 展开更多
关键词 “Plugging profile control and flooding”measures computed tomography scan nuclear magnetic resonance remaining oil recovery ratio
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Restaging rectal cancer following neoadjuvant chemoradiotherapy 被引量:1
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作者 Dajana Cuicchi Giovanni Castagna +3 位作者 Stefano Cardelli Cristina Larotonda Benedetta Petrello Gilberto Poggioli 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第5期700-712,共13页
Correct tumour restaging is pivotal for identifying the most personalised surgical treatment for patients with locally advanced rectal cancer undergoing neoadjuvant therapy,and works to avoid both poor oncological out... Correct tumour restaging is pivotal for identifying the most personalised surgical treatment for patients with locally advanced rectal cancer undergoing neoadjuvant therapy,and works to avoid both poor oncological outcome and overtreatment.Digital rectal examination,endoscopy,and pelvic magnetic resonance imaging are the recommended modalities for local tumour restaging,while chest and abdominal computed tomography are utilised for the assessment of distant disease.The optimal length of time between neoadjuvant treatment and restaging,in terms of both oncological safety and clinical effectiveness of treatment,remains unclear,especially for patients receiving prolonged total neoadjuvant therapy.The timely identification of patients who are radioresistant and at risk of disease progression remains challenging. 展开更多
关键词 Locally advanced rectal cancer RESTAGING Pelvic magnetic resonance imaging Endorectal ultrasound computed tomography scan COLONOSCOPY
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Assessment of the efficacy of reduced-radiation noncontrast computed tomography scan compared with the standard noncontrast computed tomography scan for detecting urolithiasis:A prospective single-center study
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作者 Gaurav Aggarwal Samiran Das Adhikary 《Current Urology》 2023年第1期18-24,共7页
Background:Noncontrast computed tomography(CT)scan of the kidneys,ureter and bladder is the standard investigative modality for diagnosing and following up patients with urolithiasis.With each scan,a patient receives ... Background:Noncontrast computed tomography(CT)scan of the kidneys,ureter and bladder is the standard investigative modality for diagnosing and following up patients with urolithiasis.With each scan,a patient receives radiation of 18-34 mGy.Dose considerations become pertinent because of a 10%lifetime incidence rate and higher than 50%risk of recurrence,necessitating repeated imaging in the lifetime of a stone former.Hence,this study aimed to assess the sensitivity of"reduced-radiation"CT imaging by altering scan settings to lower than the"standard"norms.Materials and methods:Altogether,222 patients(255"kidney-ureter"stone-bearing units or"renal units")with urolithiasis and patients undergoing CT for other reasons with incidental findings of renal/ureteric calculi between 2017 and 2019 were included.All patients were subjected to 3 sequential scans at tube current settings of 250 mA(CT-N/Standard),100 mA(CT-100),and 50 mA(CT-50)at a constant voltage of 120 kV.Their clinicodemographic and radiological findings were recorded and assessed for significance.Results:Of the 255 renal units,117 were between 30 and 44 years of age,75%were men.Of the 255 patients,178(70.1%)reported a first stone episode and 77 had recurrence.Lower ureteric calculi were predominant(40.4%).All calculi were identified on CT-N;CT-100 failed to detect calculi in 1 patient,and CT-50 failed in 3 patients,where all calculi were<3 mm in size.Meanwhile,none were undetected among patients with obesity.The sensitivity was 99.61%for the CT-100 and 98.82%for the CT-50,which indicated a 2.5 and 5 times lower radiation and dose/length,respectively,than CT-N.Conclusions:The reduced-radiation CT scan is safe,sensitive,and accurate for the diagnosis and follow-up of patients with urolithiasis with significantly lower radiation exposures.Our study lays the foundation to accept low-dose CT in general and CT-50 in particular,as the new"standard of care,"and attempt further dose reduction without loss of diagnostic efficacy. 展开更多
关键词 Low-dose computed tomography scan Reduced-radiation computed tomography scan Reduced-radiation imaging Ureteric colic UROLITHIASIS
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Bilateral maxillary fused second and third molars:a rare occurrence 被引量:1
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作者 Rui-Zhen Liang Jin-Tao Wu +4 位作者 You-Nong Wu Roger J Smales Ming Hu Jin-Hua Yu Guang-Dong Zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2012年第4期231-234,共4页
This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography (CBCT). A 31-year-old Chinese male, with no contributory medical or fam... This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography (CBCT). A 31-year-old Chinese male, with no contributory medical or family/social history, presented with throbbing pain in the maxillary right molar area following an unsuccessful attempted tooth extraction. Clinical examination revealed what appeared initially to be a damaged large extra cusp on the buccal aspect of the distobuccal cusp of the second molar. However, CBCT revealed that a third molar was fused to the second molar. Unexpectedly, the maxillary left third molar also was fused to the second molar, and the crown of an unerupted supernumerary fourth molar was possibly also fused to the apical root region of the second molar. Operative procedures should not be attempted without adequate radiographic investigation. CBCT allowed the precise location of the root canals of the right maxillary fused molar teeth to permit successful endodontic therapy, confirmed after 6 months. 展开更多
关键词 cone-beam computed tomography scans endodontic therapy fusion of teeth maxillary molar
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Initial computed tomography findings of invasive pulmonary aspergillosis in non-hematological patients 被引量:4
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作者 XU Si-cheng QIU Li-hua +1 位作者 LIU Wen-ya FENG Yu-lin 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第17期2979-2985,共7页
Background The computed tomography (CT) findings of invasive pulmonary aspergillosis (IPA) are unclear in non- hematological patients. The present study was a retrospective evaluation of CT images in non-hematolog... Background The computed tomography (CT) findings of invasive pulmonary aspergillosis (IPA) are unclear in non- hematological patients. The present study was a retrospective evaluation of CT images in non-hematological patients with IPA. Methods All adult patients who met the 2008 European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria for proven or probable IPA were included during a 5-year study at our institutions. Initial CT findings in our cohort were retrospectively reviewed by two independent thoracic radiologists blinded to patient demographics and clinical outcomes. The presence, pattern, and distribution of abnormalities were recorded. Results Twenty-three non-hematological patients with pathologically confirmed IPA were included in our study. Areas of ground-glass opacities were present in 14 patients (61%), which were bilateral in 10 patients and unilateral in four. This pattern mainly involved the middle and upper lung zones. Air-space consolidation was identified in 12 patients (52%), and the areas were distributed along the bronchus or subpleura in most cases. Other findings, including five small nodules (22%), three macronodules (13%), and one halo sign (4%), were less common. Conclusions CT findings of IPA in non-hematological patients frequently manifested as acute bronchopneumonia, and ground-glass opacities and air-space consolidations were the most common CT findings of IPA in these patients. 展开更多
关键词 invasive pulmonary aspergillosis fungal lung disease IMMUNOSUPPRESSION computed tomography scan
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Effect of fatigue loading-confining stress unloading rate on marble mechanical behaviors: An insight into fracture evolution analyses 被引量:6
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作者 Yu Wang Dongqiao Liu +2 位作者 Jianqiang Han Changhong Li Hao Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第6期1249-1262,共14页
Rocks in underground works usually experience rather complex stress disturbance.For this,their fracture mechanism is significantly different from rocks subjected to conventional triaxial compression conditions.The eff... Rocks in underground works usually experience rather complex stress disturbance.For this,their fracture mechanism is significantly different from rocks subjected to conventional triaxial compression conditions.The effects of stress disturbances on rock geomechanical behaviors under fatigue loading conditions and triaxial unloading conditions have been reported in previous studies.However,little is known about the dependence of the unloading rate on fatigue loading and confining stress unloading(FL-CSU)conditions that influence rock failure.In this paper,we aimed at investigating the fracture behaviors of marble under FL-CSU conditions using the post-test X-ray computed tomography(CT)scanning technique and the GCTS RTR 2000 rock mechanics system.Results show that damage accumulation at the fatigue stage can influence the final fracture behaviors of marble.The stored elastic energy for rock samples under FL-CSU tests is relatively larger compared to those under conventional triaxial tests,and the dissipated energy used to drive damage evolution and crack propagation is larger for FL-CSU tests.In FL-CSU tests,as the unloading rate increases,the dissipated energy grows and elastic energy reduces.CT scanning after the test reveals the impacts of the unloading rate on the crack pattern and a fracture degree index is therein defined in this context to represent the crack dimension.It shows that the crack pattern after FL-CSU tests depends on the unloading rate,and the fracture degree is in agreement with the analysis of both the energy dissipation and the amount of energy released.The effect of unloading rate on fracture evolution characteristics of marble is revealed by a series of FL-CSU tests. 展开更多
关键词 Fatigue loading Confining stress unloading Unloading rate Energy evolution computed tomography(CT)scanning
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Maxillary first molar with an O-shaped root morphology:report of a case 被引量:2
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作者 Yooseok Shin Yemi Kim Byoung-Duck Roh 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第4期242-244,共3页
This case report is to present a maxillary first molar with one O-shaped root, which is an extended C-shaped canal system. Patient with chronic apical periodontitis in maxillary left first molar underwent replantation... This case report is to present a maxillary first molar with one O-shaped root, which is an extended C-shaped canal system. Patient with chronic apical periodontitis in maxillary left first molar underwent replantation because of difficulty in negotiating all canals. Periapical radiographs and cone-beam computed tomography (CBCT) were taken. All roots were connected and fused to one root, and all canals seemed to be connected to form an O-shape. The apical 3 mm of the root were resected and retrograde filled with resin-modified glass ionomer. Intentional replantation as an alternative treatment could be considered in a maxillary first molar having an unusual O-shaped root. 展开更多
关键词 cone-beam computed tomography scanning intentional replantation maxillary first molar O-shape root canal anatomy
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Review of radiographic findings in COVID-19 被引量:2
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作者 Audrey E Kaufman Sonum Naidu +3 位作者 Sarayu Ramachandran Dalia S Kaufman Zahi A Fayad Venkatesh Mani 《World Journal of Radiology》 CAS 2020年第8期142-155,共14页
The purpose of this study is to review the published literature for the range ofradiographic findings present in patients suffering from coronavirus disease 2019infection. This novel corona virus is currently the caus... The purpose of this study is to review the published literature for the range ofradiographic findings present in patients suffering from coronavirus disease 2019infection. This novel corona virus is currently the cause of a worldwide pandemic.Pulmonary symptoms and signs dominate the clinical picture and radiologists arecalled upon to evaluate chest radiographs (CXR) and computed tomography (CT)images to assess for infiltrates and to define their extent, distribution andprogression. Multiple studies attempt to characterize the disease course bylooking at the timing of imaging relative to the onset of symptoms. In general,plain CXR show bilateral disease with a tendency toward the lung periphery andhave an appearance most consistent with viral pneumonia. Chest CT images aremost notable for showing bilateral and peripheral ground glass and consolidatedopacities and are marked by an absence of concomitant pulmonary nodules,cavitation, adenopathy and pleural effusions. Published literature mentioningorgan systems aside from pulmonary manifestations are relatively less common,yet present and are addressed in this review. Similarly, publications focusing onimaging modalities aside from CXR and chest CT are sparse in this evolving crisisand are likewise addressed in this review. The role of imaging is examined as it iscurrently being debated in the medical community, which is not at all surprisingconsidering the highly infectious nature of Severe Acute Respiratory Syndromecoronavirus 2. 展开更多
关键词 CORONAVIRUS COVID-19 PNEUMONIA computed tomography scan X-RAY Pandemics
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Extensive abdominal lymphangiomatosis involving the small bowel mesentery: A case report
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作者 Ayman S Alhasan Tareef S Daqqaq 《World Journal of Clinical Cases》 SCIE 2021年第32期9990-9996,共7页
BACKGROUND Abdominal lymphangiomatosis is a rare benign condition accounting for less than 1%of all the cases of lymphangiomatosis.Management usually involves radical surgical excision;however,depending upon the exten... BACKGROUND Abdominal lymphangiomatosis is a rare benign condition accounting for less than 1%of all the cases of lymphangiomatosis.Management usually involves radical surgical excision;however,depending upon the extent of involvement,patient condition,and absence of complications,conservative management can be also considered.CASE SUMMARY We present the case of a 32-year-old male who presented with short onset abdominal pain and melena.Physical examination findings were within normal limits,except for left lower abdominal tenderness.Upper gastrointestinal endoscopy was within normal limits.Abdominal and pelvic ultrasound and computed tomography(CT)scan revealed numerous,variably-sized cystic lesions within the abdominal cavity,exclusively and extensively affecting the small bowel mesentery with sparing of the retroperitoneum.The diagnosis was confirmed by CT and cytological examination.Radical surgical excision was technically impossible in this patient because of the extensive involvement of the mesentery;therefore,the patient was managed conservatively.CONCLUSION Extensive and exclusive small bowel mesentery involvement in abdominal lymphangiomatosis is rare.Imaging modalities play an important role in establishing the diagnosis and conservative management can be considered when surgery is technically impossible. 展开更多
关键词 Abdominal lymphangiomatosis MESENTERY MELENA computed tomography scan Case report
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Rare squamous cell carcinoma of the jejunum causing perforated peritonitis: A case report
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作者 Lin Xiao Lie Sun +1 位作者 Ji-Xin Zhang Yi-Sheng Pan 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第11期2295-2301,共7页
BACKGROUND Adenocarcinoma has the highest incidence among malignant tumors of the small intestine(SI).Squamous cell carcinoma(SCC)often occurs in organs covered with squamous epithelium.Primary or metastatic SCC origi... BACKGROUND Adenocarcinoma has the highest incidence among malignant tumors of the small intestine(SI).Squamous cell carcinoma(SCC)often occurs in organs covered with squamous epithelium.Primary or metastatic SCC originating from the SI is very rare,with very few cases reported in the literature.CASE SUMMARY This case report involves a 69-year-old man who developed abdominal pain after lunch.After admission,an abdominal computed tomography scan revealed perforation of the alimentary canal and multiple abnormal low-density lesions in the liver.During laparotomy,an approximately 4 cm×3 cm-sized solid tumor was found in the jejunum,located 30 cm from the Treitz ligament,with a perforation.An intestinal segment of approximately 15 cm was removed,including the perforated portion.The pathological result was SCC.In combination with liver imaging,a diagnosis of SI SCC with multiple liver metastases was considered.The patient died from hepatic failure 1 mo after the operation.CONCLUSION SI tumors are very rare compared to those originating in other digestive organs.Due to its insidious onset,the diagnosis of this disease is usually delayed.Clinicians must pay close attention to digestive symptoms such as persistent abdominal pain and melena. 展开更多
关键词 Squamous cell carcinoma Jejunal perforation PERITONITIS Abdominal computed tomography scan Case report
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Lung cancer screening, what has changed after the latest evidence?
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作者 Juan Carlos Trujillo-Reyes Luis Seijo +1 位作者 Elisabeth Martinez-Tellez Felipe Counago 《World Journal of Radiology》 CAS 2020年第7期130-136,共7页
Lung cancer(LC)is still one of the most frequent cancers with a high related mortality.Their prognosis is directly proportional to the stage at the time of diagnosis.Seventy percent are currently diagnosed in advanced... Lung cancer(LC)is still one of the most frequent cancers with a high related mortality.Their prognosis is directly proportional to the stage at the time of diagnosis.Seventy percent are currently diagnosed in advanced or locally advanced stage(higher than stage III),making a cure unlikely for the majority of patients.Developments in LC treatment are significant however they do not seem to be enough to reverse the current situation,at least,in a short period of time.Despite recent advances in treatment,primary prevention and early diagnosis appear to be the key to reduce the incidence and mortality of this disease.Many countries have developed LC screening programs based on the results of clinical trials published in recent years.The aim of this paper is to review the latest results of the NEderlands Leuvens Longkanker Screenings Onderzoek and compare them with the findings of the National Lung Screening Trial.We address the question whether it is necessary to continue discussing the evidence regarding LC screening.In both trials,there is a clear impact on LC mortality but,with a modest reduction in over all mortality.Undoubtedly,the benefit of screening can be expected to grow as low-dose computed tomographys are performed over longer periods of time. 展开更多
关键词 Lung cancer EPIDEMIOLOGY Lung cancer screening Low dose chest computed tomography scan Primary prevention Molecular biomarkers
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COVID-19 and venous thromboembolism: Known and unknown for imaging decisions
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作者 Love Patel Darshan Gandhi +3 位作者 Emily Westergard Michael Ornes Matthew Lillyblad Nedaa Skeik 《World Journal of Radiology》 2021年第3期64-74,共11页
As we continue to fight against the current coronavirus disease-2019(COVID-19)pandemic,healthcare professionals across the globe are trying to answer questions surrounding how to best help patients with the up-to-date... As we continue to fight against the current coronavirus disease-2019(COVID-19)pandemic,healthcare professionals across the globe are trying to answer questions surrounding how to best help patients with the up-to-date available science while awaiting the development of new therapies and mass vaccination.Since early in the pandemic,studies indicated a heightened risk of venous thromboembolism(VTE)in COVID-19 infected patients.There have been differing expert opinions about how to assess pretest probability of VTE in this patient population.This has been partly due to the high prevalence of respiratory failure in this patient population and the use of D-dimer as a prognostic test which is also frequently elevated in patients with COVID-19 in absence of VTE.Some experts have argued for an approach similar to usual care with testing if clinical suspicion is high enough.Some have argued for more routine screening at different points of care.Others have even suggested empiric therapeutic anticoagulation in moderate to severely ill COVID-19 patients.In the following article,we review and summarize the most current literature in hopes of assisting clinicians in decision making and guidance for when to be concerned for VTE in COVID-19 patients.We also discuss research gaps and share pathways currently being used within our institution. 展开更多
关键词 COVID-19 Venous thromboembolism computed tomography scan ANTICOAGULATION Point of care ultrasound
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Role of Radiological Investigations of COVID-19 Patients with Pneumonia, Karachi Pakistan
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作者 Samia Perwaiz Khan Safia Izhar Shazia Kadri 《Open Journal of Radiology》 2021年第1期35-44,共10页
The study was conducted to determine the role of radiological investigation in assessing the severity of COVID-19 pneumonia with the help of chest X-ray (CXR), high resolution computed tomography (HRCT), and ultrasoun... The study was conducted to determine the role of radiological investigation in assessing the severity of COVID-19 pneumonia with the help of chest X-ray (CXR), high resolution computed tomography (HRCT), and ultrasound. This was a retrospective study conducted on 105 COVID-19 patients with symptoms of fever, cough, dyspnea, loss of sense of smell and taste, body ache. Diagnostic tests PCR were positive for COVID-19 included from Medicare Cardiac and General Hospital and Jinnah Medical College Hospital Korangi (JMCH) from April to November 2020. Written informed consent was taken from all participants. This study was approved by ethical review committee, Jinnah Medical & Dental College. Real time-PCR (RT-PCR) was done for the confirmation. Radiological imaging including Chest X-ray, HRCT chest, and ultrasound was done to study the severity of symptoms. Sixty-five patients had mild to moderate symptoms with oxygen saturation between 96% - 98% and 30 patients with severe pneumonia had between saturation 50% - 55%. Patients with mild symptoms were followed up by chest X-ray showing mostly normal chest X-rays but single or patches of ground glass opacities (HRCT). HRCT of 10 patients with low oxygen saturation 50% were already done showing bilateral peripheral patchy consolidation predominantly involving mid and lower lobes. 3 patients presented with patchy lung opacities and ultrasound showing similar findings with pleural effusion and ascites. Radiological imaging, specially CT-Scan was highly significant for diagnosing COVID-19 and severity of infection even in patients with negative PCR. Chest X-ray and ultrasound were also found to be a very useful tool. 展开更多
关键词 High Resolution computed tomography Scan (HRCT-Scan) CXR-Chest X-Ray Ultrasound Ground Glass Opacities Corona Virus Disease 2019 COVID-19
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