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Unilateral biportal endoscopy for minimally invasive spinal fusion:Advancements in biomaterials and clinical outcome optimization
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作者 Song Fu Li-Chuan Hou +3 位作者 Xiao-Ling Huang Wei Zhao Feng-Ming Wang Ya-Nan Wang 《World Journal of Orthopedics》 2025年第9期32-38,共7页
Lumbar interbody fusion is essential for treating degenerative lumbar diseases.The disadvantages of open surgery have led to the evolution of minimally invasive spine surgery,including endoscopic techniques such as un... Lumbar interbody fusion is essential for treating degenerative lumbar diseases.The disadvantages of open surgery have led to the evolution of minimally invasive spine surgery,including endoscopic techniques such as unilateral biportal endoscopy(UBE).Leveraging arthroscopic principles,UBE offers superior visualization and flexibility and expands from decompression to fusion(UBE fusion).However,achieving robust UBE fusion presents challenges,such as suboptimal arthrodesis rates and implant-related complications,requiring more than surgical skill alone.Optimizing UBE fusion critically depends on the effective integration of advanced biomaterials with the surgical technique.This minireview assessed recent advances in UBE,focusing on the development of novel biomaterials,such as functionalized porous,expandable,or double-cage designs,to improve bone regeneration outcomes.These advancements address challenges,like washout of bone graft material and biologics,and utilize growth factors,such as recombinant human bone morphogenetic proteins,while exploring pathway modulation to improve outcomes.We also evaluated clinical optimization strategies involving technical refinements,fluid and hemostasis control,key complication mitigation especially concerning dural tears and hematomas,and technologies such as navigation and robotics.While UBE shows promise particularly for early recovery,its long-term success hinges on these biotechnological advancements.High-quality evidence,especially from randomized controlled trials and longterm studies,is needed to validate integrated strategies and define the optimal role of UBE fusion. 展开更多
关键词 unilateral biportal endoscopy unilateral biportal endoscopy fusion BIOMATERIALS Interbody cage Bone healing Clinical outcome
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An exceptional case of coronary artery collateralization in unilateral pulmonary artery agenesis: implications for right heart failure in the elderly
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作者 Caglar Kaya Nilay Solak 《Journal of Geriatric Cardiology》 2025年第6期600-602,共3页
Unilateral pulmonary artery agenesis(UPAA)is a rare congenital cardiovascular anomaly defined by the complete absence of one pulmonary artery,most often affecting the right side.[1]Although typically identified in chi... Unilateral pulmonary artery agenesis(UPAA)is a rare congenital cardiovascular anomaly defined by the complete absence of one pulmonary artery,most often affecting the right side.[1]Although typically identified in childhood due to symptomatic presentation,certain cases may remain undiagnosed until adulthood,particularly in asymptomatic patients or those with subtle clinical signs. 展开更多
关键词 elderly coronary artery collateralization unilateral pulmonary artery agenesis upaa unilateral pulmonary artery agenesis right heart failure congenital cardiovascular anomaly
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ANCHORING RCEP IN OPENNESS China’s unilateral market opening is accelerating high-level implementation of RCEP
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作者 China Institute for Reform and Development(CIRD)research team Chi Fulin +3 位作者 Yang Rui Kuang Xianming Wang Yuehong Jin Ye 《China Report ASEAN》 2025年第5期60-61,共2页
The Regional Comprehensive Economic Partnership(RCEP)is a significant achievement in terms of Asia’s exploration and efforts toward regional economic integration.It integrates regional economic and trade cooperation ... The Regional Comprehensive Economic Partnership(RCEP)is a significant achievement in terms of Asia’s exploration and efforts toward regional economic integration.It integrates regional economic and trade cooperation mechanisms,demonstrates the determination and capabilities of Asian countries to promote open cooperation. 展开更多
关键词 unilateral market opening high level implementation OPENNESS economic trade cooperation mechanismsdemonstrates regional comprehensive economic partnership rcep regional economic partnership RCEP ANCHORING
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Sheep with partial RXFP2 knockout exhibit normal horn phenotype but unilateral cryptorchidism
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作者 Yawei Gao Siyuan Xi +13 位作者 Bei Cai Tingjie Wu Qian Wang Peter Kalds Shuhong Huang Yuhui Wang Saizheng Han Menghao Pan Chong Yang Qifang Kou Baohua Ma Xiaolong Wang Shiwei Zhou Yulin Chen 《Journal of Integrative Agriculture》 2025年第9期3698-3702,共5页
Highlights●CRISPR/Cas9 RNP complex-based strategy demonstrates robustness and accuracy in generating gene-edited sheep.●Sheep horn development remains unaffected by partial RXFP2 knockout.●Partial RXFP2 knockout re... Highlights●CRISPR/Cas9 RNP complex-based strategy demonstrates robustness and accuracy in generating gene-edited sheep.●Sheep horn development remains unaffected by partial RXFP2 knockout.●Partial RXFP2 knockout results in unilateral cryptorchidism in sheep. 展开更多
关键词 crispr cas horn phenotype unilateral cryptorchidism partial rxfp knockout gene edited sheep partial rxfp knockout partial rxfp knockout SHEEP
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Cerebral complications after unilateral biportal endoscopic surgery:A case report
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作者 Chao Han Zhan-Yun Ren +1 位作者 Zhen-Huan Jiang Yi-Feng Luo 《World Journal of Clinical Cases》 2025年第13期29-34,共6页
BACKGROUND Unilateral biportal endoscopic(UBE)surgery has developed rapidly during the past decade.Continuous epidural space irrigation is generally considered the principal reason for cerebral complications following... BACKGROUND Unilateral biportal endoscopic(UBE)surgery has developed rapidly during the past decade.Continuous epidural space irrigation is generally considered the principal reason for cerebral complications following UBE surgery.We present a case of mental symptoms during the general anesthesia awakening period due to pneumocephalus.CASE SUMMARY A 70-year-old woman with lumbar disc herniation underwent UBE surgery stably under general anesthesia.Uncontrollable hypertension occurred immediately after transfer to the postoperative care unit,accompanied by increased heart rate and tachypnea.During the recovery process,the patient responded to external stimuli but was confused and unable to complete command actions.Neck stiff-ness and significantly increased muscle strength on the left side indicated the presence of de-cerebrate rigidity.An urgent brain computed tomography scan showed pneumocephalus compressing the brainstem.After receiving analgesia and sedation treatment,the patient was conscious three hours later and recovered rapidly.She was discharged on the fifth postoperative day and followed up for 3 months with no surgical or brain complications.CONCLUSION Cerebral complications emerging during the general anesthesia awakening period following UBE surgery are not entirely due to increased intracranial pressure.Pneumocephalus induced by dural injury may also be a potential cause. 展开更多
关键词 unilateral biportal endoscopic surgery Cerebral complication PNEUMOCEPHALUS Case report
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Treatment of lumbar disc herniation with robot combined with unilateral biportal endoscopic technology:A case report
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作者 Yan-Dong Liu Duo-Fang Xu +4 位作者 Qiang Deng Yan-Jun Zhang Tie-Feng Guo Ran-Dong Peng Jun-Jie Li 《World Journal of Clinical Cases》 SCIE 2024年第17期3235-3242,共8页
BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perfo... BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perform minimally invasive decompressive fusion of the lesioned segment,and the orthopedic surgical robot's intelligence and precision to perform percutaneous pedicle screw placement.The advancement of this procedure lies in the superposition of advantages and offsetting disadvantages of the two new technologies,and the maximum effect of treatment is achieved with maximum minimization of invasiveness and precision under the monitoring of imaging instruments to maximize the benefit of patients,and this review reports a case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE for reference.CASE SUMMARY A 44-year-old patient presented to our hospital.Combining various clinical data,we diagnosed the patient with lumbar disc herniation with radiculopathy,lumbar spondylolisthesis,and lumbar spinal stenosis.We developed a surgical plan of"UBE decompression+UBE-LIF+orthopedic surgery robot-assisted percutaneous pedicle screw implantation for internal fixation".The results were satisfactory.CONCLUSION We present an extremely rare case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE and achieved good results.Therefore,the technique is worthy of clinical promotion. 展开更多
关键词 Orthopedic robot unilateral biportal endoscopy unilateral biportal endoscopic lumbar interbody fusion Lumbar disc herniation Decompression fusion Case report
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Symmetry and Hojman Conserved Quantity of Tznoff Equations for Unilateral Holonomic System 被引量:12
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作者 ZHENG Shi-Wang Department of Physics and Information Engineering,Shangqiu Teachers College,Shangqiu 476000,ChinaXIE Jia-Fang Department of Mechanics,Beijing Institute of Technology,Beijing 100081,ChinaJIA Li-Qun College of Science,Southern Yangtze University,Wuxi 214122,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期43-47,共5页
Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tz... Symmetry of Tzénoff equations for unilateral holonomic system under the infinitesimal transformationsof groups is investigated.Its definitions and discriminant equations of Mei symmetry and Lie symmetry of Tzénoffequations are given.Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given.Hojman conserved quantity of Tzénoff equations for the system above through special Lie symmetry and Lie symmetryin the condition of special Mei symmetry respectively is obtained. 展开更多
关键词 unilateral constraint Tzénoff equations SYMMETRY Hojman conserved quantity
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Mei symmetry and Mei conserved quantity of nonholonomic systems with unilateral Chetaev type in Nielsen style 被引量:10
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作者 贾利群 解加芳 罗绍凯 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1560-1564,共5页
This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The defini... This paper studies the Mei symmetry and Mei conserved quantity for nonholonomic systems of unilateral Chetaev type in Nielsen style. The differential equations of motion of the system above are established. The definition and the criteria of Mei symmetry, loosely Mei symmetry, strictly Mei symmetry for the system are given in this paper. The existence condition and the expression of Mei conserved quantity are deduced directly by using Mei symmetry. An example is given to illustrate the application of the results. 展开更多
关键词 Nielsen style unilateral nonholonomic constrained system Mei symmetry Mei conserved quantity
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MRS study on lentiform nucleus in idiopathic Parkinson‘s disease with unilateral symptoms 被引量:16
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作者 郑旭宁 朱雄超 +4 位作者 阮凌翔 张玲菊 袁敏 商德胜 柳扬 《Journal of Zhejiang University Science》 CSCD 2004年第2期246-250,共5页
Objective: To investigate changes in magnetic resonance spectroscopy (MRS) of lentiform nucleus during the early stage of Parkinson抯 disease. Methods: Twenty-five patients with idiopathic Parkinson disease with unila... Objective: To investigate changes in magnetic resonance spectroscopy (MRS) of lentiform nucleus during the early stage of Parkinson抯 disease. Methods: Twenty-five patients with idiopathic Parkinson disease with unilateral symptoms (IPDUS) and 25 healthy volunteers were enrolled in this study. MRS of the lentiform nucleus in each patient was taken and then concentrations of N-acetylaspartate (NAA), Creatine (Cr) and Choline (Cho) were calculated. Results: Compared to that in the control, NAA/ (Cho+Cr) was significantly lower in the lentiform nucleus contralateral to symptoms and even that in the ipsilateral side in IPDUS patients (all P<0.05); while there was no difference between the two sides in the healthy volunteer (P>0.05). The ratio of NAA/(Cho+Cr) ipsilateral to the sympatomatic side of the patient was also lower than that of the control (P<0.05). Conclusions: there might be some changes with MRS on the lentiform nucleus during the early stage of idiopathic Parkinson抯 disease with unilateral symptom. MRS may be one of the reliable methods for early or even sub-clinical diagnosis. 展开更多
关键词 Idiopathic Parkinson抯 disease with unilateral symptom (IPDUS) Magnetic resonance spectroscopy N-acetyas- partate CREATINE CHOLINE
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Contrast-free air cholangiography-assisted unilateral plastic stenting in malignant hilar biliary obstruction 被引量:7
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作者 Virendra Singh Gurpreet Singh +2 位作者 Vikas Gupta Rajesh Gupta Rakesh Kapoor 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第1期88-92,共5页
BACKGROUND:Endoscopic palliation in malignant hilar biliary obstruction requires endoscopic retrograde cholangiopancreatography (ERCP),whereas contrast injection leads to cholangitis.Contrast-free metal stenting with ... BACKGROUND:Endoscopic palliation in malignant hilar biliary obstruction requires endoscopic retrograde cholangiopancreatography (ERCP),whereas contrast injection leads to cholangitis.Contrast-free metal stenting with or without magnetic resonance cholangiopancreatography (MRCP) has shown encouraging results,but MRCP and metal stents are costly.There have been no reports on the use of air cholangiography.METHODS:We prospectively evaluated the role of air cholangiography-assisted unilateral plastic stenting in 10 patients with type Ⅱ malignant hilar biliary obstruction.A retrospectively analysed group of 10 patients treated with contrast-free unilateral metal stenting served as historical controls.RESULTS:Ten patients with unresectable type Ⅱ malignant hilar biliary obstruction were studied.Air cholangiography detected type Ⅱ obstruction in all patients,similar to MRCP.The patients underwent unilateral stenting.Successful endoscopic drainage was achieved in all patients.The mean patency of the stent was 95.8±17.5 days in the study group and 143.9±115.1 days in the control group (P=0.20).The mean survival was 121.8±41.6 days in the study group and 154.9±122.5 days in the control group (P=0.42).KaplanMeier analysis showed an estimated median survival of 100:95% CI (65.9,134.1) days in the study group and 98:95% CI (84.1,111.9) days in the control group (P=0.62).Cholangitis occurred in none of the patients and there were no 30-day deaths nor major complications.Air cholangiographyassisted unilateral plastic stenting was cheaper than contrastfree unilateral metal stenting.CONCLUSION:Air cholangiography-assisted unilateral plastic stenting is as safe and effective as contrast-free unilateral metal stenting in type Ⅱ malignant hilar biliary obstruction for palliating patients,but it is cheaper. 展开更多
关键词 air cholangiogram hilar obstruction MALIGNANT plastic stent metal stent unilateral
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Lie-form invariance of non-holonomic systems with unilateral constraints 被引量:5
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作者 王静 李元成 +1 位作者 夏丽莉 后其宝 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1665-1668,共4页
In this paper the Lie-form invariance of the non-holonomic systems with unilateral constraints is studied. The definition and the criterion of the Lie-form invariance of the system are given. The generalized Hojman co... In this paper the Lie-form invariance of the non-holonomic systems with unilateral constraints is studied. The definition and the criterion of the Lie-form invariance of the system are given. The generalized Hojman conserved quantity and a new type of conserved quantity deduced from the Lie-form invariance are obtained. Finally, an example is presented to illustrate the application of the results. 展开更多
关键词 unilateral constraint non-holonomic system SYMMETRY conserved quantity
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Perturbation of Symmetries and Hojman Adiabatic Invariants for Mechanical Systems with Unilateral Holonomic Constraints 被引量:4
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作者 ZHANG Yi FAN Cun-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4期607-610,共4页
The perturbation of symmetries and adiabatic invariants for mechanical systems with unilateral holonomic constraints are studied. The exact invariant in the form of Hojman led by special Lie symmetries for an undistur... The perturbation of symmetries and adiabatic invariants for mechanical systems with unilateral holonomic constraints are studied. The exact invariant in the form of Hojman led by special Lie symmetries for an undisturbed system with unilateral constraints is given. Based on the concept of high-order adiabatic invariant of mechanical systems, the perturbation of Lie symmetries for the system under the action of small disturbance is investigated, and a new adiabatic invariant for the system with unilateral holonomic constraints is obtained, which can be called Hojman adiabatic invariant. In the end of the paper, an example is given to illustrate the application of the results. 展开更多
关键词 unilateral constraint Lie symmetry PERTURBATION exact invariant adiabatic invariant
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Heavy oil component characterization with multi-dimensional unilateral NMR 被引量:4
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作者 Liu Huabing Xiao Lizhi +6 位作者 Guo Baoxin Zhang Zongfu Zong Fangrong Deng Feng Yu Huijun V.Anferov S.Anferova 《Petroleum Science》 SCIE CAS CSCD 2013年第3期402-407,共6页
Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficien... Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficiency. A designed unilateral Nuclear Magnetic Resonance (NMR) sensor with a Larmor frequency of 20 MHz and a well-defined constant gradient of 23.25 T/m was employed to acquire three- dimensional (3D) data for three heavy oil samples. The highly-constant gradient is advantageous for diffusion coefficient measurement of heavy oil. A fast data-implementation procedure including specially designed 3D pulse sequence and Inversion Laplace Transform (ILT) algorithm was adopted to process the data and extract 3D T1-D-T2 probability function. It indicates that NMR relaxometry and diffusometry are useful to characterize the components of heavy oil samples. NMR results were compared with independent measurements of fractionation and gas chromatography analysis. 展开更多
关键词 Heavy oil multi-dimensional NMR unilateral sensor
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Structural Equation and Mei Conserved Quantity of Mei Symmetry for Appell Equations in Holonomic Systems with Unilateral Constraints 被引量:4
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作者 JIA Li-Qun ZHANG Yao-Yu +1 位作者 CUI Jin-Chao LUO Shao-Kai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期572-576,共5页
Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomi... Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomie mechanic systems with unilateral constraints axe established. The definition and the criterion of Mei symmetry for Appell equations in holonomic systems with unilateral constraints under the infinitesimal transformations of groups axe also given. The expressions of the structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 holonomic system with unilateral constraints Appell equation structural equation of Mei symmetry Mei conserved quantity
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A DIFFERENTIAL GEOMETRIC DESCRIPTION FOR TIME-INDEPENDENT CHETAEV'S NONHOLONOMIC MECHANICAL SYSTEM WITH UNILATERAL CONSTRAINTS 被引量:4
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作者 Zhang Yi (Department of Urban Constrution,University of Science & Technology of Suzhou,Suzhou 215011,China)Mei Fengxiang (Department of Applied Mechanics,Beijing Institute of Technology,Beijing 100081,China) 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第1期62-67,共6页
By applying the framework of the tangent bundle geometry to the method of Lagrange multi- pliers,a geometric description of Chetaev's nonholonomic systems subjected to unilateral nonholonomic con- straints trod un... By applying the framework of the tangent bundle geometry to the method of Lagrange multi- pliers,a geometric description of Chetaev's nonholonomic systems subjected to unilateral nonholonomic con- straints trod unilateral holonomic constraints respectively in time-independent circumstances is presented. 展开更多
关键词 analytical mechanics unilateral constraint differential geometry nonholonomic constraint tangent bundle geometry
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Combined intra-arterial chemotherapy and intravitreal melphalan for the treatment of advanced unilateral retinoblastoma 被引量:3
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作者 Ting-Yi Liang Xiu-Yu Zhu +2 位作者 Xu-Ming Hua Xun-Da Ji Pei-Quan Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期257-262,共6页
●AIM:To evaluate the efficacy and safety of combined intraarterial chemotherapy(IAC)and intravitreal melphalan(IVM)for the treatment of advanced unilateral retinoblastoma.●METHODS:This retrospective study involved 3... ●AIM:To evaluate the efficacy and safety of combined intraarterial chemotherapy(IAC)and intravitreal melphalan(IVM)for the treatment of advanced unilateral retinoblastoma.●METHODS:This retrospective study involved 30 consecutive eyes from 30 Chinese patients with advanced unilateral retinoblastoma.All patients were initially treated with IAC combined with IVM.The clinical status and complications were recorded at each visit.●RESULTS:The International Intraocular Retinoblastoma Classification groups were D in 23 eyes and E in 7 eyes.All eyes showed severe cloud vitreous seeds at the first visit.The mean number of IAC cycles and intravitreal injections was 3.2(range,3-4)and 6(range,1-14),respectively.The median follow-up time was 29 mo(range,7-36 mo).Treatment success with regression of the retinal tumor and vitreous seeds was achieved in 29 of 30 eyes(96.7%).Globe salvage was attained in 93.3%(28/30)eyes,and enucleation(n=2)was per formed due to neovascular glaucoma and persistent vitreous hemorrhage.Complications included retinal pigment epithelium(RPE)atrophy(n=13;43%),mild lens opacity(n=7;23%),vitreous hemorrhage(n=5;17%)and rhegmatogenous retinal detachment(n=1;3%).No extraocular tumor extension or metastasis occurred.●CONCLUSION:Combined IAC and IVM is effective and safe for the treatment of advanced unilateral retinoblastoma. 展开更多
关键词 intra-arterial CHEMOTHERAPY INTRAVITREAL CHEMOTHERAPY MELPHALAN RETINOBLASTOMA ADVANCED stage unilateral disease
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A type of new conserved quantity deduced from Mei symmetry for Appell equations in a holonomic system with unilateral constraints 被引量:3
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作者 贾利群 解银丽 +1 位作者 张耀宇 杨新芳 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期48-52,共5页
A type of new conserved quantity deduced from Mei symmetry of Appell equations for a holonomic system with unilateral constraints is investigated. The expressions of new structural equation and new conserved quantity ... A type of new conserved quantity deduced from Mei symmetry of Appell equations for a holonomic system with unilateral constraints is investigated. The expressions of new structural equation and new conserved quantity deduced from Mei symmetry of Appell equations for a holonomic system with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 unilateral constraint Appell equation Mei symmetry conserved quantity
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Generalized Lutzky Conserved Quantities of Holonomic Systems with Remainder Coordinates Subjected to Unilateral Constraints 被引量:2
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作者 ZHANG Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期732-736,共5页
This paper focuses on studying the relation between a velocity-dependent symmetry and a generalized Lutzky conserved quantity for a holonomic system with remainder coordinates subjected to unilateral constraints. The ... This paper focuses on studying the relation between a velocity-dependent symmetry and a generalized Lutzky conserved quantity for a holonomic system with remainder coordinates subjected to unilateral constraints. The differential equations of motion of the system are established, and the definition of Lie symmetry for the system is given. The conditions under which a Lie symmetry can directly lead up to a generalized Lutzky conserved quantity and the form of the new conserved quantity are obtained, and an example is given to illustrate the application of the results. 展开更多
关键词 analytical mechanics remainder coordinate unilateral constraint holonomic system SYMMETRY conserved quantity
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Inertial parameter estimation and control of non-cooperative target with unilateral contact constraint 被引量:2
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作者 Shuang LI Yuchen SHE Jun SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第3期225-240,共16页
In this paper, the relative sliding motion between the target and the manipulator’s endeffector is considered and characterized as a unilateral contact constraint. A new possible solution is presented to estimate the... In this paper, the relative sliding motion between the target and the manipulator’s endeffector is considered and characterized as a unilateral contact constraint. A new possible solution is presented to estimate the inertial parameters of a non-cooperative target while the relative sliding motion exists. First, the detailed analysis of the dynamical model is presented, and a parameterexplicit linear time-varying model is obtained. Then, an extended state observer is constructed based on the new model, which can effectively estimate the unknown inertial parameters of the target when relative sliding motion exists. As the modified reactionless controller requires the knowledge of inertial parameters, a hybrid post-capture control scheme is also established based on the switch law between different controllers. The correctness and efficiency of the proposed algorithm are validated by numerical simulation, which proves a potential framework for the non-cooperative target postcapture operation. 展开更多
关键词 Non-cooperative object On-orbit servicing Post-capture control Parameter estimation unilateral contact constraint
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Reduction in interhemispheric functional connectivity in the dorsal visual pathway in unilateral acute open globe injury patients: a resting-state fMRI study 被引量:3
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作者 Lei Ye Ran Wei +9 位作者 Xin Huang Wen-Qing Shi Qi-Chen Yang Qing Yuan Pei-Wen Zhu Nan Jiang Biao Li Qiong Zhou Fu-Qing Zhou Yi Shao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第6期1056-1060,共5页
This study investigated the changes in interhemispheric functional connectivity (FC) of the whole brain in open globe injury (OGI) patients, using voxel-mirrored homotopic connectivity (VMHC), and their relation... This study investigated the changes in interhemispheric functional connectivity (FC) of the whole brain in open globe injury (OGI) patients, using voxel-mirrored homotopic connectivity (VMHC), and their relationships with clinical features. Totally, 16 male and 2 female acute OGI patients and 18 sex, age, and education-matched healthy volunteers were enrolled in the study. All subjects were scanned through functional magnetic resonance imaging (fMRI). Receiver operating characteristic (ROC) curves analyses had been used to identify the VMHC in these brain areas could be used as biomarkers to distinguish OGI and from healthy control (HC). The mean VMHC values in multiple brain areas and clinical OGI manifestations were evaluated with a Pearson correlation analysis. OGI patients had significantly decreased VMHC in the bilateral calcarine/lingual/cuneus (BA18, 19, 30) and middle occipital gyrus (BA18, 19). The OGI patients had abnormal interhemispheric FC in the dorsal visual pathway, which may represent the pathophysiological mechanism that underlies acute vision loss after OGI. 展开更多
关键词 unilateral acute open globe injury voxelmirrored homotopic connectivity resting state functional magnetic resonance imaging
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