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Adjacent segment disease following Dynesys stabilization for lumbar disorders:A case series of mid-and long-term follow-ups 被引量:3
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作者 Kuan-Ju Chen Chien-Ying Lai +7 位作者 Lu-Ting Chiu Wei-Sheng Huang Pang-Hsuan Hsiao Chien-Chun Chang Cheng-Jyh Lin Yuan-Shun Lo Yen-Jen Chen Hsien-Te Chen 《World Journal of Clinical Cases》 SCIE 2021年第35期10850-10860,共11页
BACKGROUND Radiologic adjacent segment degeneration(ASDeg)can occur after spinal surgery.Adjacent segment disease(ASDis)is defined as the development of new clinical symptoms corresponding to radiographic changes adja... BACKGROUND Radiologic adjacent segment degeneration(ASDeg)can occur after spinal surgery.Adjacent segment disease(ASDis)is defined as the development of new clinical symptoms corresponding to radiographic changes adjacent to the level of previous spinal surgery.Greater pre-existing ASDeg is generally considered to result in more severe ASDis;nonetheless,whether the ASDeg status before index surgery influences the postoperative risk of revision surgery due to ASDis warrants investigation.AIM To identify possible risk factors for ASDis and verify the concept that greater preexisting ASDeg leads to more severe ASDis.METHODS Data from 212 patients who underwent posterior decompression with Dynesys stabilization from January 2006 to June 2016 were retrospectively analyzed.Patients who underwent surgery for ASDis were categorized as group A(n=13),whereas those who did not were classified as group B(n=199).Survival analysis and Cox proportional hazards models were used to compare the modified Pfirrmann grade,University of California-Los Angeles grade,body mass index,number of Dynesys-instrumented levels,and age.RESULTS The mean time of reoperation was 7.22(1.65–11.84)years in group A,and the mean follow-up period was 6.09(0.10–12.76)years in group B.No significant difference in reoperation risk was observed:Modified Pfirrmann grade 3 vs 4(P=0.53)or 4 vs 5(P=0.46)for the upper adjacent disc,University of California-Los Angeles grade 2 vs 3 for the upper adjacent segment(P=0.66),age of<60 vs>60 years(P=0.9),body mass index<25 vs>25 kg/m2(P=0.3),and sex(P=0.8).CONCLUSION Greater preexisting upper ASDeg was not associated with a higher rate of reoperation for ASDis after Dynesys surgery.Being overweight tended to increase reoperation risk after Dynesys surgery for ASDis. 展开更多
关键词 adjacent segment degeneration adjacent segment disease Degenerative lumbar spondylolisthesis Dynamic stabilization DYNESYS Spinal stenosis
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Adjacent Segment Disease after Long Spinal Fusion Ending at L5 for Adult Spinal Deformity: A Retrospective Cohort Study
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作者 Ryota Kimura Michio Hongo +6 位作者 Eiji Abe Takahi Kobayashi Kazuma Kikuchi Hayato Kinoshita Yuji Kasukawa Daisuke Kudo Naohisa Miyakoshi 《Open Journal of Orthopedics》 2022年第6期268-276,共9页
Study Design: This is a retrospective cohort study using data from the adult spinal deformity (ASD) database of a single institution. Purpose: To investigate the incidence of proximal junctional failure and distal jun... Study Design: This is a retrospective cohort study using data from the adult spinal deformity (ASD) database of a single institution. Purpose: To investigate the incidence of proximal junctional failure and distal junctional failure (DJF) after ASD surgery with a lower instrumented vertebra (LIV) at L5. Overview of Literature: Spinopelvic fixation from the lower thoracic vertebra to the pelvis is the current gold standard treatment for ASD. However, the LIV at L5 is acceptable in some cases. Methods: Fifty-six patients who underwent corrective surgery for ASD with LIV at L5 were included. The upper instrumented vertebra (UIV) was T7 in one patient, T9 in 14, T10 in three, T11 in four, T12 in eight, L1 in 10, and L2 in 16. Regarding clinical parameters, age, sex, curve types of Scoliosis Research Society-Schwab classification, number of levels fused, follow-up period, hip bone mallow density, revision surgery rate, and radiographic measurements were compared between the T (UIV: T7 - 10) and TL (UIV: T11 - L2) groups. Results: The revision surgery rate was 19.6% overall. In the T and TL groups, it was 27.8%, and 15.8%, respectively (p = 0.305). The rate of DJF in the T group (33.3%) was significantly higher than in the TL group (5.3%). The rate of proximal junctional kyphosis in the T group (55.6%) was higher than in the TL group (28.9%), with no significant difference. The mean global alignment, sagittal vertical axis, and C7 plumb line-central sacral vertical line were not different between both groups. Conclusions: ASD surgery with LIV set at L5 and UIV set at the thoracic vertebrae (T7 - T10) has a risk of adjacent segment disease. 展开更多
关键词 adjacent segment disease Adult Spinal Deformity Spinal Long Fusion L5 Distal Junctional Failure Proximal Junctional Failure
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Prone Transpsoas Approach for Adjacent Segment Disease and Flatback Deformity: Technical Note and Case Report
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作者 Timothy E. O’Connor Mary Margaret O’Hehir +2 位作者 Jennifer Z. Mao Jeffrey P. Mullin John Pollina 《Open Journal of Modern Neurosurgery》 2021年第1期20-28,共9页
The prone transpsoas approach is a relatively new technique to correct segmental kyphosis and global sagittal imbalance in a minimally invasive fashion. Here, we provide a detailed case report using the prone transpso... The prone transpsoas approach is a relatively new technique to correct segmental kyphosis and global sagittal imbalance in a minimally invasive fashion. Here, we provide a detailed case report using the prone transpsoas approach to address adjacent segment disease and flatback deformity. This technique allows considerable restoration of segmental lordosis with lateral interbody placement and posterior decompression and fusion using a single position approach. Our experience with the surgical technique and the advantages and challenges unique to this approach are discussed. 展开更多
关键词 Prone Transpsoas adjacent segment disease Flatback Deformity
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Optimizing Fully Convolutional Encoder-Decoder Network for Segmentation of Diabetic Eye Disease
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作者 Abdul Qadir Khan Guangmin Sun +2 位作者 Yu Li Anas Bilal Malik Abdul Manan 《Computers, Materials & Continua》 SCIE EI 2023年第11期2481-2504,共24页
In the emerging field of image segmentation,Fully Convolutional Networks(FCNs)have recently become prominent.However,their effectiveness is intimately linked with the correct selection and fine-tuning of hyperparamete... In the emerging field of image segmentation,Fully Convolutional Networks(FCNs)have recently become prominent.However,their effectiveness is intimately linked with the correct selection and fine-tuning of hyperparameters,which can often be a cumbersome manual task.The main aim of this study is to propose a more efficient,less labour-intensive approach to hyperparameter optimization in FCNs for segmenting fundus images.To this end,our research introduces a hyperparameter-optimized Fully Convolutional Encoder-Decoder Network(FCEDN).The optimization is handled by a novel Genetic Grey Wolf Optimization(G-GWO)algorithm.This algorithm employs the Genetic Algorithm(GA)to generate a diverse set of initial positions.It leverages Grey Wolf Optimization(GWO)to fine-tune these positions within the discrete search space.Testing on the Indian Diabetic Retinopathy Image Dataset(IDRiD),Diabetic Retinopathy,Hypertension,Age-related macular degeneration and Glacuoma ImageS(DR-HAGIS),and Ocular Disease Intelligent Recognition(ODIR)datasets showed that the G-GWO method outperformed four other variants of GWO,GA,and PSO-based hyperparameter optimization techniques.The proposed model achieved impressive segmentation results,with accuracy rates of 98.5%for IDRiD,98.7%for DR-HAGIS,and 98.4%,98.8%,and 98.5%for different sub-datasets within ODIR.These results suggest that the proposed hyperparameter-optimized FCEDN model,driven by the G-GWO algorithm,is more efficient than recent deep-learning models for image segmentation tasks.It thereby presents the potential for increased automation and accuracy in the segmentation of fundus images,mitigating the need for extensive manual hyperparameter adjustments. 展开更多
关键词 Diabetic eye disease image segmentation deep learning artificial intelligence grey wolf optimization FCN CNN
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Adjacent segment disease after anterior cervical decompression and fusion: analysis of risk factors on X-ray and magnetic resonance imaging 被引量:2
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作者 Zhao Yanbin Sun Yu Zhou Feifei Wang Shaobo Zhang Fengshan Pan Shengfa 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第22期3867-3870,共4页
关键词 核磁共振成像 危险因素 X射线 颈椎 成像分析 病变 节段 邻近
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Enhanced Wolf Pack Algorithm (EWPA) and Dense-kUNet Segmentation for Arterial Calcifications in Mammograms
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作者 Afnan M.Alhassan 《Computers, Materials & Continua》 SCIE EI 2024年第2期2207-2223,共17页
Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly women.Thus identifying BAC could provide an expense,and be inaccurate.Recently Deep Learning(DL)method... Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly women.Thus identifying BAC could provide an expense,and be inaccurate.Recently Deep Learning(DL)methods have been introduced for automatic BAC detection and quantification with increased accuracy.Previously,classification with deep learning had reached higher efficiency,but designing the structure of DL proved to be an extremely challenging task due to overfitting models.It also is not able to capture the patterns and irregularities presented in the images.To solve the overfitting problem,an optimal feature set has been formed by Enhanced Wolf Pack Algorithm(EWPA),and their irregularities are identified by Dense-kUNet segmentation.In this paper,Dense-kUNet for segmentation and optimal feature has been introduced for classification(severe,mild,light)that integrates DenseUNet and kU-Net.Longer bound links exist among adjacent modules,allowing relatively rough data to be sent to the following component and assisting the system in finding higher qualities.The major contribution of the work is to design the best features selected by Enhanced Wolf Pack Algorithm(EWPA),and Modified Support Vector Machine(MSVM)based learning for classification.k-Dense-UNet is introduced which combines the procedure of Dense-UNet and kU-Net for image segmentation.Longer bound associations occur among nearby sections,allowing relatively granular data to be sent to the next subsystem and benefiting the system in recognizing smaller characteristics.The proposed techniques and the performance are tested using several types of analysis techniques 826 filled digitized mammography.The proposed method achieved the highest precision,recall,F-measure,and accuracy of 84.4333%,84.5333%,84.4833%,and 86.8667%when compared to other methods on the Digital Database for Screening Mammography(DDSM). 展开更多
关键词 Breast arterial calcification cardiovascular disease semantic segmentation transfer learning enhanced wolf pack algorithm and modified support vector machine
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Exploring kidney biopsy findings in congenital heart diseases:Insights beyond cyanotic nephropathy
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作者 Jose Daniel Juarez-Villa Iván Zepeda-Quiroz +7 位作者 Sebastián Toledo-Ramírez Victor Hugo Gomez-Johnson Francisco Pérez-Allende Brian Ricardo Garibay-Vega Francisco E Rodríguez Castellanos Bernardo Moguel-González Edgar Garcia-Cruz Salvador Lopez-Gil 《World Journal of Nephrology》 2024年第1期25-32,共8页
BACKGROUND The association between congenital heart disease and chronic kidney disease is well known.Various mechanisms of kidney damage associated with congenital heart disease have been established.The etiology of k... BACKGROUND The association between congenital heart disease and chronic kidney disease is well known.Various mechanisms of kidney damage associated with congenital heart disease have been established.The etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis(FSGS),however,this has only been demonstrated in case reports and not in observational or clinical trials.AIM To identify baseline and clinical characteristics,as well as the findings in kidney biopsies of patients with congenital heart disease in our hospital.METHODS This is a retrospective observational study conducted at the Nephrology Depart-ment of the National Institute of Cardiology“Ignacio Chávez”.All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the study.RESULTS Ten patients with congenital heart disease and kidney biopsy were found.The average age was 29.00 years±15.87 years with pre-biopsy proteinuria of 6193 mg/24 h±6165 mg/24 h.The most common congenital heart disease was Fallot’s tetralogy with 2 cases(20%)and ventricular septal defect with 2(20%)cases.Among the 10 cases,one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found,receiving specific treatment after histopathological diagnosis,delaying the initiation of kidney replacement therapy.Among remaining 8 cases(80%),one case of FSGS with perihilar variety was found,while the other 7 cases were non-specific FSGS.CONCLUSION Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement therapy.In 2 out of 10 patients in our study,interventions were performed,and initiation of kidney replacement therapy was delayed.Prospective studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease. 展开更多
关键词 Renal biopsy Congenital heart disease Chronic kidney disease Focal segmental glomerulosclerosis
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Automatic image segmentation method for cotton leaves with disease under natural environment 被引量:9
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作者 ZHANG Jian-hua KONG Fan-tao +2 位作者 WU Jian-zhai HAN Shu-qing ZHAI Zhi-fen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第8期1800-1814,共15页
In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segme... In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segmented monotone decreasing edge composite function is proposed to accelerate the evolution of the level set curve in the gradient smooth region. Secondly, canny edge detection operator gradient is introduced into the model as the global information. In the process of the evolution of the level set function, the guidance information of the energy function is used to guide the curve evolution according to the local information of the image, and the smooth contour curve is obtained. And the main direction of the evolution of the level set curve is controlled according to the global gradient information, which effectively overcomes the local minima in the process of the evolution of the level set function. Finally, the Heaviside function is introduced into the energy function to smooth the contours of the motion and to increase the penalty function Φ(x) to calibrate the deviation of the level set function so that the level set is smooth and closed. The results showed that the model of cotton leaf edge profile curve could be obtained in the model of cotton leaf covered by bare soil, straw mulching and plastic film mulching, and the ideal edge of the ROI could be realized when the light was not uniform. In the complex background, the model can segment the leaves of the cotton with uneven illumination, shadow and weed background, and it is better to realize the ideal extraction of the edge of the blade. Compared with the Geodesic Active Contour(GAC) algorithm, Chan-Vese(C-V) algorithm and Local Binary Fitting(LBF) algorithm, it is found that the model has the advantages of segmentation accuracy and running time when processing seven kinds of cotton disease leaves images, including uneven lighting, leaf disease spot blur, adhesive diseased leaf, shadow, complex background, unclear diseased leaf edges, and staggered condition. This model can not only conduct image segmentation of cotton leaves under natural conditions, but also provide technical support for the accurate identification and diagnosis of cotton diseases. 展开更多
关键词 local BINARY FITTING model natural environment COTTON disease LEAVES image segmentation
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Real-Time Multiple Guava Leaf Disease Detection from a Single Leaf Using Hybrid Deep Learning Technique 被引量:1
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作者 Javed Rashid Imran Khan +3 位作者 Ghulam Ali Shafiq ur Rehman Fahad Alturise Tamim Alkhalifah 《Computers, Materials & Continua》 SCIE EI 2023年第1期1235-1257,共23页
The guava plant has achieved viable significance in subtropics and tropics owing to its flexibility to climatic environments,soil conditions and higher human consumption.It is cultivated in vast areas of Asian and Non... The guava plant has achieved viable significance in subtropics and tropics owing to its flexibility to climatic environments,soil conditions and higher human consumption.It is cultivated in vast areas of Asian and Non-Asian countries,including Pakistan.The guava plant is vulnerable to diseases,specifically the leaves and fruit,which result in massive crop and profitability losses.The existing plant leaf disease detection techniques can detect only one disease from a leaf.However,a single leaf may contain symptoms of multiple diseases.This study has proposed a hybrid deep learning-based framework for the real-time detection of multiple diseases from a single guava leaf in several steps.Firstly,Guava Infected Patches Modified MobileNetV2 and U-Net(GIP-MU-NET)has been proposed to segment the infected guava patches.The proposed model consists of modified MobileNetv2 as an encoder,and the U-Net model’s up-sampling layers are used as a decoder part.Secondly,the Guava Leaf SegmentationModel(GLSM)is proposed to segment the healthy and infected leaves.In the final step,the Guava Multiple Leaf Diseases Detection(GMLDD)model based on the YOLOv5 model detects various diseases from a guava leaf.Two self-collected datasets(the Guava Patches Dataset and the Guava Leaf Diseases Dataset)are used for training and validation.The proposed method detected the various defects,including five distinct classes,i.e.,anthracnose,insect attack,nutrition deficiency,wilt,and healthy.On average,the GIP-MU-Net model achieved 92.41%accuracy,the GLSM gained 83.40%accuracy,whereas the proposed GMLDD technique achieved 73.3%precision,73.1%recall,71.0%mAP@0.5 and 50.3 mAP@0.5:0.95 scores for all the aforesaid classes. 展开更多
关键词 Guava leaf diseases guava leaf segmentation guava patches segmentation multiple leaf diseases guava leaf diseases dataset
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Transition from minimal change disease to focal segmental glomerulosclerosis related to occupational exposure:A case report
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作者 Long Tang Zhen Cai +1 位作者 Su-Xia Wang Wen-Jing Zhao 《World Journal of Clinical Cases》 SCIE 2022年第17期5861-5868,共8页
BACKGROUND Although minimal change disease(MCD)and focal segmental glomerulosclerosis(FSGS)have been described as two separate forms of nephrotic syndrome(NS),they are not completely independent.We report a case of a ... BACKGROUND Although minimal change disease(MCD)and focal segmental glomerulosclerosis(FSGS)have been described as two separate forms of nephrotic syndrome(NS),they are not completely independent.We report a case of a patient transitioning from MCD to FSGS,review the literature,and explore the relationship between the two diseases.CASE SUMMARY A 42-year-old male welder,presenting with lower extremity edema and elevated serum creatinine,was diagnosed with NS and end-stage kidney disease(ESKD)based on laboratory test results.The patient had undergone a kidney biopsy for NS 20 years previously,which indicated MCD,and a second recent kidney biopsy suggested FSGS.The patient was an electric welder with excessive levels of cadmium and lead in his blood.Consequently,we suspect that his aggravated pathology and occurrence of ESKD were related to metal nephrotoxicity.The patient eventually received kidney replacement therapy and quit his job which involved long-term exposure to metals.During the 1-year follow-up period,the patient was negative for metal elements in the blood and urine and recovered partial kidney function.CONCLUSION MCD and FSGS may be different stages of the same disease.The transition from MCD to FSGS in this case indicates disease progression,which may be related to excessive metal contaminants caused by the patient’s occupation. 展开更多
关键词 Minimal change disease Focal segmental glomerulosclerosis Occupational exposure CADMIUM LEAD Case report
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Vessels Segmentation in Angiograms Using Convolutional Neural Network: A Deep Learning Based Approach
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作者 Sanjiban Sekhar Roy Ching-Hsien Hsu +3 位作者 Akash Samaran Ranjan Goyal Arindam Pande Valentina E.Balas 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期241-255,共15页
Coronary arterydisease(CAD)has become a significant causeof heart attack,especially amongthose 40yearsoldor younger.There is a need to develop new technologies andmethods to deal with this disease.Many researchers hav... Coronary arterydisease(CAD)has become a significant causeof heart attack,especially amongthose 40yearsoldor younger.There is a need to develop new technologies andmethods to deal with this disease.Many researchers have proposed image processing-based solutions for CADdiagnosis,but achieving highly accurate results for angiogram segmentation is still a challenge.Several different types of angiograms are adopted for CAD diagnosis.This paper proposes an approach for image segmentation using ConvolutionNeuralNetworks(CNN)for diagnosing coronary artery disease to achieve state-of-the-art results.We have collected the 2D X-ray images from the hospital,and the proposed model has been applied to them.Image augmentation has been performed in this research as it’s the most significant task required to be initiated to increase the dataset’s size.Also,the images have been enhanced using noise removal techniques before being fed to the CNN model for segmentation to achieve high accuracy.As the output,different settings of the network architecture undoubtedly have achieved different accuracy,among which the highest accuracy of the model is 97.61%.Compared with the other models,these results have proven to be superior to this proposed method in achieving state-of-the-art results. 展开更多
关键词 ANGIOGRAM convolution neural network coronary artery disease diagnosis of CAD image segmentation
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A Hybrid Approach for Plant Disease Detection Using E-GAN and CapsNet
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作者 N.Vasudevan T.Karthick 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期337-356,共20页
Crop protection is a great obstacle to food safety,with crop diseases being one of the most serious issues.Plant diseases diminish the quality of crop yield.To detect disease spots on grape leaves,deep learning techno... Crop protection is a great obstacle to food safety,with crop diseases being one of the most serious issues.Plant diseases diminish the quality of crop yield.To detect disease spots on grape leaves,deep learning technology might be employed.On the other hand,the precision and efficiency of identification remain issues.The quantity of images of ill leaves taken from plants is often uneven.With an uneven collection and few images,spotting disease is hard.The plant leaves dataset needs to be expanded to detect illness accurately.A novel hybrid technique employing segmentation,augmentation,and a capsule neural network(CapsNet)is used in this paper to tackle these challenges.The proposed method involves three phases.First,a graph-based technique extracts leaf area from a plant image.The second step expands the dataset using an Efficient Generative Adversarial Network E-GAN.Third,a CapsNet identifies the illness and stage.The proposed work has experimented on real-time grape leaf images which are captured using an SD1000 camera and PlantVillage grape leaf datasets.The proposed method achieves an effective classification of accuracy for disease type and disease stages detection compared to other existing models. 展开更多
关键词 Feature extraction neural network disease segmentATION pattern analysis
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Ophthalmic posterior segment manifestations of COVID-19
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作者 Sonya Besagar Archana A.Nair Sapna Gangaputra 《Annals of Eye Science》 2023年第4期16-21,共6页
Since the onset of the coronavirus disease 2019(COVID-19)pandemic,numerous reports of associated ocular manifestations have emerged.Involvement of nearly every ocular structure has been reported.The aim of this review... Since the onset of the coronavirus disease 2019(COVID-19)pandemic,numerous reports of associated ocular manifestations have emerged.Involvement of nearly every ocular structure has been reported.The aim of this review is to describe various manifestations of the severe acute respiratory disease coronavirus 2(SARS-CoV-2)virus on the eye,focused primarily on the posterior segment,and discuss proposed pathophysiology and mechanisms of involvement of these ophthalmic structures.Proposed mechanisms of ocular involvement of COVID-19 parallel those of systemic manifestations and include viral and other microbial reactivation,primary infection,inflammation,and thromboembolism.Viral reactivation of Herpes Simplex Virus,Varicella Zoster Virus,and Epstein-Barr Virus has been presumed in cases of acute retinal necrosis(ARN),while bacterial and parasitic infections have also been reported albeit less commonly.Primary infection has also been thought to contribute to various inflammatory presentations.Thromboembolic manifestations include various retinal artery and vein occlusions among other less visually significant signs such as cotton wool spots.Cranial neuropathies including optic neuropathy,as well as optic neuritis have also been widely reported.COVID-19 vaccines are increasingly associated with ocular signs and syndromes.In this paper we explore various reported ophthalmic manifestations of COVID-19 infection,primarily involving the posterior segment.Given the novel nature of the virus and overall paucity of cases,further study is required to better elucidate the causal relationship between the virus and its ophthalmologic effects. 展开更多
关键词 Coronavirus disease 2019(COVID-19) CORONAVIRUS posterior segment UVEITIS
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计算机辅助设计三维牙颌分割及应用场景
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作者 崔家礼 黄敏慧 +2 位作者 刘东林 贾瑞明 李涵 《中国组织工程研究》 CAS 北大核心 2024年第2期252-257,共6页
背景:传统的三维牙颌模型分割方法通常利用预定义的空间几何特征如曲率、法向量等作为牙齿分割的参考信息。目的:提出一种适用于复杂三维牙颌分割的算法并深度挖掘分割结果与应用场景之间的关联性。方法:建立基于结构特征和空间特征双... 背景:传统的三维牙颌模型分割方法通常利用预定义的空间几何特征如曲率、法向量等作为牙齿分割的参考信息。目的:提出一种适用于复杂三维牙颌分割的算法并深度挖掘分割结果与应用场景之间的关联性。方法:建立基于结构特征和空间特征双流提取的三维牙颌分割算法,利用分流的模块化设计避免特征混淆。其中,结构特征流上的注意力机制用于捕获牙齿分割所需的细粒度语义信息,空间特征流上的Tran-Net用于保证模型对复杂牙颌分割的鲁棒性。该算法在包含健康牙颌和缺牙、错牙、牙列拥挤等复杂牙颌的临床数据集上验证有效性和可靠性,通过总体精度、均交并比、方向切割差异等评价指标衡量模型的分割性能。结果与结论:该算法在临床数据集上的总体分割精度为97.08%,分割效果从定性和定量的角度均优于其他竞争方法。验证了此次设计的结构特征流,通过构建注意力聚合机制从坐标和法向信息中可提取更精细齿形局部细节,设计的空间特征流通过构建变换网络(Tran-Net)可保证模型对缺牙、错牙、牙列拥挤等复杂牙颌的鲁棒性。因此,该牙齿分割算法对于临床医生实操参考具有较强的可靠性。 展开更多
关键词 口腔疾病预防 牙齿矫正 神经网络 三维牙颌分割 可靠性
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基于BERT-BiLSTM-CRF模型的畜禽疫病文本分词研究
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作者 余礼根 郭晓利 +3 位作者 赵红涛 杨淦 张俊 李奇峰 《农业机械学报》 EI CAS CSCD 北大核心 2024年第2期287-294,共8页
针对畜禽疫病文本语料匮乏、文本内包含大量疫病名称及短语等未登录词问题,提出了一种结合词典匹配的BERT-BiLSTM-CRF畜禽疫病文本分词模型。以羊疫病为研究对象,构建了常见疫病文本数据集,将其与通用语料PKU结合,利用BERT(Bidirectiona... 针对畜禽疫病文本语料匮乏、文本内包含大量疫病名称及短语等未登录词问题,提出了一种结合词典匹配的BERT-BiLSTM-CRF畜禽疫病文本分词模型。以羊疫病为研究对象,构建了常见疫病文本数据集,将其与通用语料PKU结合,利用BERT(Bidirectional encoder representation from transformers)预训练语言模型进行文本向量化表示;通过双向长短时记忆网络(Bidirectional long short-term memory network,BiLSTM)获取上下文语义特征;由条件随机场(Conditional random field,CRF)输出全局最优标签序列。基于此,在CRF层后加入畜禽疫病领域词典进行分词匹配修正,减少在分词过程中出现的疫病名称及短语等造成的歧义切分,进一步提高了分词准确率。实验结果表明,结合词典匹配的BERT-BiLSTM-CRF模型在羊常见疫病文本数据集上的F1值为96.38%,与jieba分词器、BiLSTM-Softmax模型、BiLSTM-CRF模型、未结合词典匹配的本文模型相比,分别提升11.01、10.62、8.3、0.72个百分点,验证了方法的有效性。与单一语料相比,通用语料PKU和羊常见疫病文本数据集结合的混合语料,能够同时对畜禽疫病专业术语及疫病文本中常用词进行准确切分,在通用语料及疫病文本数据集上F1值都达到95%以上,具有较好的模型泛化能力。该方法可用于畜禽疫病文本分词。 展开更多
关键词 畜禽疫病 文本分词 预训练语言模型 双向长短时记忆网络 条件随机场
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基于双分支点流语义先验的路面病害分割模型
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作者 庞荣 杨燕 +2 位作者 冷雄进 张朋 刘言 《智能系统学报》 CSCD 北大核心 2024年第1期153-164,共12页
针对基于深度学习的真实路面病害图像识别算法主要面临的复杂道路背景与病害前景比例不同、病害尺度小等导致的类别严重不平衡、路面病害与道路的几何结构特征对比不明显导致其不易识别等问题,本文提出一种基于双分支语义先验网络,用于... 针对基于深度学习的真实路面病害图像识别算法主要面临的复杂道路背景与病害前景比例不同、病害尺度小等导致的类别严重不平衡、路面病害与道路的几何结构特征对比不明显导致其不易识别等问题,本文提出一种基于双分支语义先验网络,用于指导自注意力骨干特征网络挖掘背景与病害前景的复杂关系,运用高效自注意力机制和互协方差自注意力机制分别对二维空间和特征通道进行语义特征提取,并引入语义局部增强模块提高局部特征聚合能力。本文提出了一种新的稀疏主体点流模块,并与传统特征金字塔网络相结合,进一步缓解路面病害的类别不平衡问题;构建了一个真实场景的道路病害分割数据集,并在该数据集和公开数据集上与多个基线模型进行对比实验,实验结果验证了本模型的有效性。 展开更多
关键词 语义先验信息 高效注意力机制 互协方差注意力机制 稀疏主体点流 类别不平衡 语义分割 路面病害 深度学习
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经皮内镜减压治疗腰椎融合术后邻近节段疾病
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作者 张树文 地力木拉提·艾克热木 王浩 《中国微创外科杂志》 CSCD 北大核心 2024年第4期255-260,共6页
目的观察经皮内镜减压治疗腰椎融合术后邻近节段疾病的临床疗效。方法回顾性分析我院2020年1月~2022年6月26例经皮内镜减压治疗腰椎融合术后邻近节段疾病的临床资料,其中经椎间孔入路11例,经椎板间入路15例。单侧减压21例,双侧减压5例... 目的观察经皮内镜减压治疗腰椎融合术后邻近节段疾病的临床疗效。方法回顾性分析我院2020年1月~2022年6月26例经皮内镜减压治疗腰椎融合术后邻近节段疾病的临床资料,其中经椎间孔入路11例,经椎板间入路15例。单侧减压21例,双侧减压5例。用疼痛视觉模拟评分(Visual Analogue Scale,VAS)、Oswestry功能障碍指数(Oswestry Disability Index,ODI)、日本骨科协会(Japanese Orthopedic Association,JOA)评分和改良MacNab标准评估疗效。结果手术均顺利完成,未出现并发症。手术时间(85.4±21.7)min,手术出血量(19.8±5.9)ml,术中透视次数(7.7±2.4)次。术后即刻下肢疼痛VAS评分显著降低(P=0.000)。术后随访10~24个月,(16.0±3.7)月。术后3个月、末次随访VAS评分及ODI较术前均显著降低(F=105.444、852.714,均P=0.000),JOA评分显著增加(F=256.222,P=0.000)。末次随访疗效为优18例(69.2%),良5例(19.2%),可3例(11.5%),优良率88.5%(23/26)。结论经皮内镜减压治疗腰椎融合术后邻近节段疾病能够获得较好的临床疗效。 展开更多
关键词 经皮内镜技术 邻近节段退变 邻近节段疾病
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退变性腰椎滑脱行减压融合可影响脊柱矢状面的失衡
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作者 史浩冉 关海山 +1 位作者 王悦勇 刘涛 《中国组织工程研究》 CAS 北大核心 2024年第12期1956-1961,共6页
背景:腰椎减压融合是治疗腰椎退行性滑脱最有效的手术方式。近几年来脊柱矢状面平衡被广泛认为是调节脊柱手术患者结局的关键因素,能够影响脊柱矢状面平衡的因素间接影响手术疗效和预后。目的:归纳并总结因退变性腰椎滑脱行减压融合术... 背景:腰椎减压融合是治疗腰椎退行性滑脱最有效的手术方式。近几年来脊柱矢状面平衡被广泛认为是调节脊柱手术患者结局的关键因素,能够影响脊柱矢状面平衡的因素间接影响手术疗效和预后。目的:归纳并总结因退变性腰椎滑脱行减压融合术时可以影响脊柱矢状面平衡相关危险因素,对腰椎滑脱的手术治疗起到一定参考作用。方法:以“腰椎滑脱,脊柱矢状面平衡,手术治疗,危险因素”为中文检索词,以“lumbar spondylolisthesis,sagittal balance,risk factor”为英文检索词,分别检索PubMed、Springer、ScienceDirect、万方、维普及中国知网数据库。检索时间范围主要为2010年1月至2023年1月,同时纳入少数经典远期文献。通过阅读文题和摘要进行初步筛选;排除中英文文献重复性研究、低质量期刊及内容不相关的文献,最后纳入67篇文献进行综述。结果与结论:(1)退行性腰椎滑脱是造成椎管狭窄和腰椎不稳的一个重要因素,也是产生下腰痛和间歇性跛行的主要病因。腰椎减压融合内固定是治疗退行性腰椎滑脱切实有效的方法。(2)以往的减压融合固定治疗退行性腰椎滑脱重点在于彻底神经根探查松解、滑脱椎体复位以及牢靠的内固定,而对于脊柱矢状面平衡关注较少。(3)随着腰椎减压融合内固定术的普及,因脊柱矢状面失衡造成的并发症逐渐增多,从而导致患者预后差,甚至二次手术风险增加。(4)以往的研究仅讨论腰椎矢状面参数与脊柱矢状面平衡的相关性,未深入研究造成脊柱矢状面失衡的相关因素。(5)文章结果表明,开放式腰椎固定融合、滑脱椎体完全复位、选用较粗的椎弓根螺钉、选用较大型号融合器以及自体骨移植是维持矢状面平衡的有利因素,而融合节段数越多、融合节段平面越高,是影响矢状面失衡的危险因素。 展开更多
关键词 腰椎滑脱 矢状面平衡 脊柱-骨盆矢状位失衡 邻近节段退行性改变 融合固定 脊柱 内固定
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经皮椎间孔镜下椎间盘切除术对治疗改良经椎间孔腰椎椎体间融合术后相邻节段病变的疗效与安全性
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作者 陆宣宇 袁硕 +3 位作者 藏磊 梅语奇 范宁 杜鹏 《骨科临床与研究杂志》 2024年第3期145-150,共6页
目的探讨经皮椎间孔镜下椎间盘切除术对治疗改良经椎间孔腰椎椎体间融合术后相邻节段病变的临床疗效与安全性。方法选取在2016年7月至2022年7月于首都医科大学附属北京朝阳医院骨科接受了经皮椎间孔镜下椎间盘切除术(PTED)的45例改良经... 目的探讨经皮椎间孔镜下椎间盘切除术对治疗改良经椎间孔腰椎椎体间融合术后相邻节段病变的临床疗效与安全性。方法选取在2016年7月至2022年7月于首都医科大学附属北京朝阳医院骨科接受了经皮椎间孔镜下椎间盘切除术(PTED)的45例改良经椎间孔腰椎椎体间融合术后相邻节段病变(ASDis)患者资料进行回顾性研究。使用背部疼痛视觉模拟量表(VAS-BP)和腿部疼痛视觉模拟量表(VAS-LP)以及Oswestry残疾指数(ODI)评估患者术前、术后即刻、术后3、12个月以及最终随访时的临床结果。根据改良MacNab评分对患者治疗效果进行评估。结果与术前相比,患者的VAS-BP、VAS-LP及ODI评分均有显著改善(P<0.001),88.89%(40/45)的患者在最终随访时的改良MacNab评分为优或良。患者在术后即刻观察到临床症状改善,临床评分在术后随访期间保持稳定。患者术中及术后均未出现严重并发症。结论PTED是治疗邻近节段病变有效且安全的手术方式,具有创伤小,恢复快的优势。 展开更多
关键词 经皮经椎间孔镜下椎间盘切除术 邻近节段退变 腰椎间盘突出 临床疗效
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