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Pseudoaneurysm formation following transarterial embolization of traumatic carotid-cavernous fistula with detachable balloon:An institutional cohort long-term study
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作者 Prasert Iampreechakul Korrapakc Wangtanaphat +5 位作者 Songpol Chuntaroj Yodkhwan Wattanasen Sunisa Hangsapruek Punjama Lertbutsayanukul Pimchanok Puthkhao Somkiet Siriwimonmas 《World Journal of Radiology》 2024年第4期94-108,共15页
BACKGROUND The goal of therapy for traumatic carotid-cavernous fistula(TCCF)is the elimination of fistula while maintaining patency of the parent artery.The treatment for TCCF has evolved from surgery to endovascular ... BACKGROUND The goal of therapy for traumatic carotid-cavernous fistula(TCCF)is the elimination of fistula while maintaining patency of the parent artery.The treatment for TCCF has evolved from surgery to endovascular management using detachable balloons,coils,liquid embolic agents,covered stents,or flow-diverter stent through arterial or venous approaches.Despite the withdrawal of detachable balloons from the market in the United States since 2004,transarterial embolization with detachable balloons has currently remained the best initial treatment for TCCF in several countries.However,the pseudoaneurysm formation following transarterial detachable balloon embolization has rarely been observed in long-term follow-up.AIM To determine the occurrence and long-term follow-up of pseudoaneurysm after transarterial detachable balloon for TCCF.METHODS Between January 2009 and December 2019,79 patients diagnosed with TCCF were treated using detachable latex balloons(GOLDBAL)of four sizes.Pseudoaneurysm sizes were stratified into five grades for analysis.Initial and follow-up assessments involved computed tomography angiography at 1 month,6 month,1 year,and longer intervals for significant cases.Clinical follow-ups occurred semi-annually for 2 years,then annually.Factors analyzed included sex,age,fistula size and location,and balloon size.RESULTS In our cohort of 79 patients treated for TCCF,pseudoaneurysms formed in 67.1%,with classifications ranging from grade 0 to grade 3;no grade 4 or giant pseudoaneurysms were observed.The majority of pseudoaneurysms did not progress in size,and some regressed spontaneously.Calcifications developed in most large pseudoaneurysms over 5-10 years.Parent artery occlusion occurred in 7.6%and recurrent fistulas in 16.5%.The primary risk factors for pseudoaneurysm formation were identified as the use of specific balloon sizes,with balloon SP and No.6 significantly associated with its occurrence(P=0.005 and P=0.002,respectively),whereas sex,age,fistula size,location,and the number of balloons used were not significant predictors.CONCLUSION Pseudoaneurysm formation following detachable balloon embolization for TCCF is common,primarily influenced by the size of the balloon used.Despite this,all patients with pseudoaneurysms remained asymptomatic during long-term follow-up. 展开更多
关键词 Pseudoaneurysm formation Traumatic carotid-cavernous fistula Direct carotid-cavernous fistula Transarterial embolization Detachable balloon Endovascular treatment Computed tomography angiography long-term follow-up
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Long-term chorioretinal changes following strabismus surgery——possible occult needle penetration 被引量:1
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作者 Victor M.Villegas Stephen G.Schwartz +1 位作者 Craig A.McKeown Harry W.Flynn Jr 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期518-519,共2页
Dear Editor,cleral penetration during strabismus surgery was k3 first reported over 50 years ago[1].Early manuscripts reported the incidence of this complication around 10%[1].However,more recent studies suggest that ... Dear Editor,cleral penetration during strabismus surgery was k3 first reported over 50 years ago[1].Early manuscripts reported the incidence of this complication around 10%[1].However,more recent studies suggest that this rate may have decreased[2-3]. 展开更多
关键词 IRB POSSIBLE OCCULT needle penetration long-term chorioretinal CHANGES following STRABISMUS surgery
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Long-term survival following radiofrequency ablation of colorectal liver metastases: A retrospective study 被引量:11
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作者 Simeon Niyi Babawale Thomas MandФe Jensen Jens BrФndum FrФkjr 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2015年第3期33-38,共6页
AIM: To retrospectively evaluate the long-term survivalof patients that received radiofrequency ablation(RFA) therapies of colorectal liver metastases. METHODS: In 2005 to 2008, RFA of 105 colorectal liver metastases(... AIM: To retrospectively evaluate the long-term survivalof patients that received radiofrequency ablation(RFA) therapies of colorectal liver metastases. METHODS: In 2005 to 2008, RFA of 105 colorectal liver metastases(CRLM) were performed on 49 patients in our institution. The liver metastases were evaluated, both before and after ablation therapies, with contrast enhanced computerised tomography and contrast enhanced ultrasonography. Histological evidence of malignant liver metastases was obtained in the few instances where contrast enhanced ultrasonography gave equivocal results. Accesses to the CRLM were guided ultrasonically in all patients. The data obtained from records of these ablations were retrospectively analysed and survival data were compared with existing studies in the literature.RESULTS: 1-, 2-, 3-, 4- and 5-year survival rates, when no stringent selection criteria were applied, were 92%, 65%, 51%, 41% and 29% respectively. To explore the impact of the number and size of CRLM on patients' survival, an exclusion of 13 patients(26.5%) with number of CRLM ≥ 5 and tumour size ≥ 40 mm resulted in 1-, 2-, 3-, 4- and 5-year survival rates improving to 94%, 69%, 53%, 42% and 31% respectively. It is of note that 9 of 49 patients developed extra-hepatic metastases, not visible or seen on pretreatment scans, just after RFA treatment. These patients had poorer survival. The development of extra-hepatic metastases in nearly 20% of the patients included in our study can partly account for modestly lower survival rates as compared with earlier studies in the literature.CONCLUSION: Our study underscores the fact that optimum patients' selection before embarking on RFA treatment is vitally important to achieving a superior outcome. 展开更多
关键词 Colorectal cancer Liver metastasis Radiofrequency ablation long-term survival Ablation success
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Quality of life following laparoscopic Nissen fundoplication: Assessing short-term and long-term outcomes 被引量:7
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作者 Ilmo Kellokumpu Markku Voutilainen +3 位作者 Caj Haglund Martti Frkkil Peter J Roberts Hannu Kautiainen 《World Journal of Gastroenterology》 SCIE CAS 2013年第24期3810-3818,共9页
AIM: To investigate the quality of life following lapa-roscopic Nissen fundoplication by assessing short-term and long-term outcomes. METHODS: From 1992 to 2005, 249 patients under-went laparoscopic Nissen fundoplicat... AIM: To investigate the quality of life following lapa-roscopic Nissen fundoplication by assessing short-term and long-term outcomes. METHODS: From 1992 to 2005, 249 patients under-went laparoscopic Nissen fundoplication. Short-term outcome data including symptom response, side effects of surgery, endoscopy, and patient's perception of over-all success were collected prospectively. Long-term out-comes were investigated retrospectively in patients witha median follow-up of 10 years by assessment of reflux symptoms, side effects of surgery, durability of antire-flux surgery, need for additional treatment, patient's perception of success, and quality of life. Antireflux sur-gery was considered a failure based on the following criteria: moderate to severe heartburn or regurgitation; moderate to severe dysphagia reported in combination with heartburn or regurgitation; regular proton pump inhibitor medication use; endoscopic evidence of erosive esophagitis Savary-Miller grade 1-4; pathological 24-h pH monitoring; or necessity to undergo an additional surgery. The main outcome measures were short-and long-term cure rates and quality of life, with patient sat-isfaction as a secondary outcome measure. RESULTS: Conversion from laparoscopy to open sur-gery was necessary in 2.4% of patients. Mortality was zero and the 30-d morbidity was 7.6% (95%CI: 4.7%-11.7%). The median postoperative hospital stay was 2 d [interquartile range (IQR) 2-3 d]. Two hundred and forty-seven patients were interviewed for short-term analysis following endoscopy. Gastro-esophageal reflux disease was cured in 98.4% (95%CI: 95.9%-99.6%) of patients three months after surgery. New-onset dysphagia was encountered postoperatively in 13 patients (6.7%); 95% reported that the outcome was better after antireflux surgery than with preopera-tive medical treatment. One hundred and thirty-nine patients with a median follow-up of 10.2 years (IQR 7.2-11.6 years) were available for a long-term evalu-ation. Cumulative long-term cure rates were 87.7% (81.0%-92.2%) at 5 years and 72.9% (64.0%-79.9%) at 10 years. Gastrointestinal symptom rating scores and RAND-36 quality of life scores of patients with treatment success were similar to those of the general population but significantly lower in those with failed antireflux surgery. Of the patients available for long-term follow-up, 83% rated their operation a success. CONCLUSION: For the long-term, our results indicate decreasing effectiveness of laparoscopic antirefluxsurgery, although most of the patients seem to have an overall quality of life similar to that of the general population. 展开更多
关键词 LAPAROSCOPY NISSEN FUNDOPLICATION long-term outcome ANTIREFLUX Gastrointestinal SYMPTOM rating SCORES RAND-36
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Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework
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作者 Jintao Zhang Xingling Shao +1 位作者 Wendong Zhang Zongyu Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期278-287,共10页
This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the fe... This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution. 展开更多
关键词 Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following
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Path-Following Based on Nonlinear Model Predictive Control with Adaptive Path Preview
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作者 Jun-Ting LI Chih-Keng CHEN 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期158-164,共7页
This paper presents a Nonlinear Model Predictive Controller(NMPC)for the path following of autonomous vehicles and an algorithm to adaptively adjust the preview distance.The prediction model includes vehicle dynamics,... This paper presents a Nonlinear Model Predictive Controller(NMPC)for the path following of autonomous vehicles and an algorithm to adaptively adjust the preview distance.The prediction model includes vehicle dynamics,path following dynamics,and system input dynamics.The single-track vehicle model considers the vehicle’s coupled lateral and longitudinal dynamics,as well as nonlinear tire forces.The tracking error dynamics are derived based on the curvilinear coordinates.The cost function is designed to minimize path tracking errors and control effort while considering constraints such as actuator bounds and tire grip limits.An algorithm that utilizes the optimal preview distance vector to query the corresponding reference curvature and reference speed.The length of the preview path is adaptively adjusted based on the vehicle speed,heading error,and path curvature.We validate the controller performance in a simulation environment with the autonomous racing scenario.The simulation results show that the vehicle accurately follows the highly dynamic path with small tracking errors.The maximum preview distance can be prior estimated and guidance the selection of the prediction horizon for NMPC. 展开更多
关键词 path following curvilinear coordinates nonlinear model predictive control
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A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles
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作者 Zirui Chen Jingchuan Tang Zongyu Zuo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1476-1484,共9页
The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlle... The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled vehicle.In this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol approach.Furthermore,the interdependence among the pre-scribed parameters is discussed.To validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach. 展开更多
关键词 Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control
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Long-term survival following heart transplantation is possible 被引量:1
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作者 Li Junquan An Shoukuan Qiao Youjin Xia Qiuming 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第3期173-179,共7页
Objective:To determine whether long-term survival(>10 years) after heart transplantation is possible and identify complications influencing long-term survival.Methods:We analyzed clinical outcomes in the group of 2... Objective:To determine whether long-term survival(>10 years) after heart transplantation is possible and identify complications influencing long-term survival.Methods:We analyzed clinical outcomes in the group of 21 patients who had undergone heart transplantation at the Second Affiliated Hospital of Harbin Medical University since 1992 and 4 of them survived more than 10 years.Results:Nine patients are still alive with normal left ventricular function,and 4 of them have survived more than 10 years.The longest survival patient has lived more than 18 years after transplantation,whose survival is the longest in China and in Asia.We have also found that there has been a high incidence of complications,such as rejection episodes during the first 6 months,and transplant vasculopathy in the long-term survival patients.Conclusion:Long-term survivors maintain normal hemodynamic function of their allografts,and long-term survival following cardiac transplantation is possible.Aggressive preventive and therapeutic measures are essential to limit the risk factors for development of complications such as rejection episodes and transplant vasculopathy,and enable long-term survival after cardiac transplantation. 展开更多
关键词 Heart transplantation long-term survival Graft coronary artery disease
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Effect of long-term low dose of aspirin on severity of disease following onset of acute cerebral infarction
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作者 Jun Xu Lili Cao Xiaomei Deng Enji Han 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期67-69,共3页
BACKGROUND: Aspirin can decrease the incidence risk of high-risk crowdgroup of cerebral infarction, but there are still controversy if it might decrease the degree of disease in degree of patients with acute cerebral... BACKGROUND: Aspirin can decrease the incidence risk of high-risk crowdgroup of cerebral infarction, but there are still controversy if it might decrease the degree of disease in degree of patients with acute cerebral infarction. OBJECTIVE: To observe the effect of lower dose of aspirin during taking for a long time on disease degree of disease following onset of acute cerebral infarction. DESIGN: Grouping according to the admission time and 1:1 paired observation.SETTING : Department of Neurology, Qilu Hospital of Shandong University.PARTICIPANTS : The participants in present study were 321 patients with acute cerebral infarction who received treatments in the Department of Neurology, Qilu Hospital of Shandong University from January 1999 to June 2000. There were 190 male and 131 female ,with mean (65±11 )years of age. Inclusive criteria: ① A focal neurological disturbance occurred suddenly and had lasted for more than 24 hours, patients were admitted within 3 days after onset of disease; ② A computed tomography of the brain was performed and excluded hemorrhage in all patients; ③ The patients were proved internal carotid occlusions by clinical features and image findings; ④ The functions of limbs were normal (before the first stroke) or almost normal (before the second stroke). Exclusive criteria:①The patients who had have cardiogenic cerebral embolism; ②The patients who had taken warfarin orally and other platelet agglutination drugs. METHODS :①All the patients were divided into 2 groups according to whether they had taken aspirin before: aspirin-treated group (n=110) and blank control group (n=211). there were 70 male and 40 female in aspirin-treated group, with average(65±10) years of age.All patients had taken 50-100 mg/d aspirin for 6 months to 10 years before onset. There were 120 male and 91 female in blank control group, with average (65±13) years of age. Patients received a clinical scoring within 3 days and similar therapeutic measures (such as anti-platelet agglutination, improving cerebral circulation and metabolism-promoting reagent). Two groups of patients had the same basic conditions except for taking aspirin or not before. ②The matched pairs were made between 50 cases selected from aspirin-treated group and 50 cases from non-aspirin-treated groups according to age, gender, and other stroke risk factors. ③ Evaluation: Degree of disease after onset was evaluated by means of Acute Cerebral Infarction Clinical Neurologic Impairment Degree Scoring Standard of Carotid Artery System. MAIN OUTCOME MEASURES: Acute Cerebral Infarction Clinical Neurologic Impairment Degree Scoring Standard of Carotid Artery System. RESULTS : All 321 patients entered the stage of analysis with no loss in the midway. ① The symptom following onset of acute cerebral infarction was evaluated with clinical neurologic impairment scoring criteria, there were no significant differences between aspirin group and blank control group [(17.39±9.90) vs (16.22 ± 9.98) (t=1.025, P〉 0.05)]. ② No significant differences were found in 1:1 matched pairs of 100 cases from aspirin group and blank control group (t=1.74, P 〉 0.05). CONCLUSION : Taking a lower dose of aspirin during long time may not decrease the degree of disease following onset of acute cerebral infarction. 展开更多
关键词 Effect of long-term low dose of aspirin on severity of disease following onset of acute cerebral infarction
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Imperative for long-term management and surveillance in Kawasaki disease
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作者 Yan Pan Fu-Yong Jiao 《World Journal of Clinical Cases》 SCIE 2025年第4期61-63,共3页
Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD pat... Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical Cases.This editorial emphasizes the critical need for long-term management and regular surveillance to prevent such complications.By drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures. 展开更多
关键词 Kawasaki disease long-term management Coronary artery aneurysm SURVEILLANCE Preventive care
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Early and long-term postoperative management following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy 被引量:5
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作者 Dario Baratti Shigeki Kusamura +2 位作者 Barbara Laterza Maria Rosaria Balestra Marcello Deraco 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2010年第1期36-43,共8页
Peritoneal surface malignancies have been traditionally regarded as end-stage conditions amenable to merely palliative options. The combination of aggressive cytoreductive surgery (CRS), involving peritonectomy proced... Peritoneal surface malignancies have been traditionally regarded as end-stage conditions amenable to merely palliative options. The combination of aggressive cytoreductive surgery (CRS), involving peritonectomy procedures and multivisceral resections, with intra-operative hyperthermic intra-peritoneal chemotherapy (HIPEC) and/or early postoperative intra-peritoneal chemotherapy (EPIC) to treat the microscopic residual tumor is a new concept. In recent years, promising results have been reported for peritoneal mesothelioma and carcinomatosis of gastrointestinal and gynaecologic origin treated by this combined protocol. However, CRS with HIPEC and/or EPIC is a complex procedure associated with high rates of potentially life-threatening complications. Furthermore, disease progression following comprehensive treatment is not uncommon and represents a relevant cause of treatment failure. The present paper reviews the available information on early postoperative management and long-term follow-up in patients treated with CRS and intraperitoneal chemotherapy. The peculiar clinical and biological alterations that can be expected during an uncomplicated postoperative course, as compared to standard digestive surgery, are discussed. Early recognition and appropriate management of the most common adverse events are addressed, in order to minimize the impact of treatment-related morbidity on survival and quality of life results. Since re-operative surgery with additional HIPEC, has proven to be useful in selected patients with recurrent disease, long-term surveillance aiming at early detection of postoperative disease progression has become a relevant issue. Current results on follow-up investigations are presented. 展开更多
关键词 PERITONEAL surface MALIGNANCIES Cytoreductive surgery Hyperthermic INTRAPERITONEAL CHEMOTHERAPY Hyperthermic intra-peritoneal CHEMOTHERAPY follow-UP
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Original Article: Prognostic Factors of Long-Term Outcome and Functional Status Following Spontaneous Cerebellar Hemorrhage
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作者 Chia-Hung Sun Shin-Tsu Chang +4 位作者 Liang-Cheng Chen Heng-Yi Chu Shang-Lin Chiang Tsung-Ying Li Yung-Tsan Wu 《World Journal of Cardiovascular Diseases》 2014年第3期93-98,共6页
Cerebellar hemorrhage (CH) has a higher early mortality rate compared with other types of intracranial hemorrhage and the survivors often suffer from momentous disability. Hence, the prognostic factors of long-term ou... Cerebellar hemorrhage (CH) has a higher early mortality rate compared with other types of intracranial hemorrhage and the survivors often suffer from momentous disability. Hence, the prognostic factors of long-term outcome beyond 6 months after CH are clinically valuable, however only three studies were reported in the literature. Sixty-one patients with CH were retrospectively analyzed at least 6 months after hemorrhage. The long-term outcome of all patients and long-term functional status of survivors beyond 6 months (the patients who died within 6 months after hemorrhage were excluded) were assessed using the modified Rankin Scale (mRS): favorable outcome (mRS 0 - 2) and unfavorable outcome (mRS 3 - 6). All of the prognostic factors were analyzed by univariate and multivariate Cox proportional hazards regression models. There were 16 (26.2%) patients in the favorable outcome group and 45 (73.8%) in the unfavorable outcome group with respect of long-term outcome in all patients. The radiological brainstem compression (HR = 3;p = 0.015) was shown to be an independent predictor. On the other hand, 46 out of 61 (75.4%) patients survived beyond 6 months. In total, 16 (34.7%) patients had a favorable functional status, and 65.3% (30/46) had a persistent unfavorable functional status. Moreover, only age 365 years (HR = 3;p = 0.019) was an independent predictor. Radiological brainstem compression and age 365 were respectively shown to be a strong prognostic factor for long-term outcome and functional status among survivors beyond 6 months after hemorrhage in patients with CH. 展开更多
关键词 PROGNOSTIC Factor long-term OUTCOME CEREBELLAR HEMORRHAGE
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Changes in weight and metabolic parameters following long-term iloperidone use: A meta-analysis of data from 9 Phase II and III trials of iloperidone
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作者 Marla Hochfeld Saeeduddin Ahmed +1 位作者 Xiangyi Meng Adam Winseck 《Open Journal of Psychiatry》 2012年第4期414-422,共9页
Objective: To determine the impact of iloperidone treatment on metabolic parameters. Methods: Data were analyzed from 3210 patients who received iloperidone and 587 patients who received placebo for up to 2 years duri... Objective: To determine the impact of iloperidone treatment on metabolic parameters. Methods: Data were analyzed from 3210 patients who received iloperidone and 587 patients who received placebo for up to 2 years during 9 Phase II and Phase III studies (integrated safety database). Patients were pooled by most frequent iloperidone dose into 3 groups: 4 - 8 mg/d, 10 - 16 mg/d, and 20 - 24 mg/d. Laboratory data from 8 studies were random (fasting and nonfasting) while patients from 1 study (n = 447) were all sampled at fasting. Results: Mean (standard deviation [SD]) weight gain from baseline to endpoint was 2.1 (6.8) kg for all patients on iloperidone. Fasting mean (SD) total cholesterol changes from baseline to end of study were 8.2 (31.6) for iloperidone and -2.2 (35.2) mg/dL for placebo. Fasting mean (SD) triglyceride changes during this period were iloperidone: -0.83 (82.3);placebo: 16.5 (113.1) mg/dL. Fasting mean (SD) glucose changes were iloperidone: 6.6 (24.0);placebo: -0.05 (17.0) mg/dL from baseline to end of study. Glycosylated hemoglobin levels were unchanged following iloperidone treatment. Conclusion: These data suggest a metabolic profile for iloperidone of modest weight gain accompanied by small changes in lipids and glucose that are unlikely to be of clinical concern. 展开更多
关键词 DYSLIPIDEMIA GLUCOSE ILOPERIDONE long-term METABOLIC WEIGHT
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缺乏位置信息的视觉移动机器人leader-following编队控制
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作者 沈尧高 于双和 黄进 《计算机应用与软件》 北大核心 2024年第2期73-79,共7页
针对视觉移动机器人编队在缺乏位置信息情况下的控制问题,提出一种基于视觉的leader-following编队反馈控制方法。该方法利用leader标志物特征点在follower摄像机像平面上的坐标信息设计了观测器,对leader与follower间的相对位置进行估... 针对视觉移动机器人编队在缺乏位置信息情况下的控制问题,提出一种基于视觉的leader-following编队反馈控制方法。该方法利用leader标志物特征点在follower摄像机像平面上的坐标信息设计了观测器,对leader与follower间的相对位置进行估计,基于相对位置估计量与它们速度的关系,设计出leader-following编队反馈控制器,通过Lyapunov理论证明了闭环系统的稳定性。仿真结果表明,该控制方法能有效解决缺乏位置信息情况下视觉移动机器人编队的控制问题。 展开更多
关键词 视觉移动机器人 leader-following编队 缺乏位置信息 相对位置 反馈控制
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Visual object-oriented application for lane following on intelligent highway system
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作者 王春燕 王炜 +1 位作者 陆建 常玉林 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期165-167,共3页
A visual object-oriented software for lane following on intelligent highway system (IHS) is proposed. According to object-oriented theory, 3 typical user services of self-check, transfer of human driving and automatic... A visual object-oriented software for lane following on intelligent highway system (IHS) is proposed. According to object-oriented theory, 3 typical user services of self-check, transfer of human driving and automatic running and abnormal information input from the sensors are chosen out. In addition, the functions of real-time display, information exchanging interface, determination and operation interweaving in the 3 user services are separated into 5 object-oriented classes. Moreover, the 5 classes are organized in the visual development environment. At last, experimental result proves the validity and reliability of the control application. 展开更多
关键词 intelligent transportation system intelligent highway system lane following visual object-oriented application
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MICROPROCESSOR BASED MODEL FOLLOWING ADAPTIVE CONTROL SYSTEM FOR CSIM DRIVES
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作者 张春明 左敦稳 王珉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期40+35-39,共6页
A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is ... A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is reduced to simplify the design without degrading much of the performance. Model following adaptive control laws in discrete form are derived. These laws satisfy the hyperstability condition for taking care of the load and machine parameter changes of the drive. A microprocessor 8098 is used to develop the speed controller. The implementation of the control system uses only available variables of the reference model and the controlled plant. Experimental results are given to demonstrate the good performance of the system. 展开更多
关键词 induction motors frequency converters microprocessors adaptive control model following
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基于时变时滞动态拓扑的二阶Leader-Following多智能体一致性分析 被引量:7
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作者 缪盛 崔宝同 朱夏冰 《计算机应用研究》 CSCD 北大核心 2013年第4期1024-1027,共4页
针对具有时变时滞的二阶Leader-Following多智能体系统,研究了其一致性问题。假设其通信拓扑是时刻切换的,并且每个子时间段内系统拓扑不完全连通,采用Lyapunov-Krasovskii泛函和矛盾分析法,对系统进行了解耦分析,得出只需所有时间段内... 针对具有时变时滞的二阶Leader-Following多智能体系统,研究了其一致性问题。假设其通信拓扑是时刻切换的,并且每个子时间段内系统拓扑不完全连通,采用Lyapunov-Krasovskii泛函和矛盾分析法,对系统进行了解耦分析,得出只需所有时间段内的拓扑并集连通,且系统的特征根满足一定条件,系统能达到一致,并进行了理论证明。以4个following智能体与1个leader智能体做成的网络为例进行具体说明,所得仿真结果验证了理论的有效性。 展开更多
关键词 二阶一致 多智能体系统 领航者 动态拓扑 时变时滞 并集连通
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Leader-following多智能体网络分布式编队控制 被引量:2
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作者 李本印 《宁夏大学学报(自然科学版)》 CAS 2013年第4期321-326,共6页
针对多智能体固定拓扑网络,考虑无时延和有时延两种情况,研究了多智能体网络的分布式编队控制协议.首先,针对无通信时延的多智能体网络,提出了分布式编队控制协议,利用Lyapunov稳定理论,给出了协议有效的充分条件.然后,考虑时变通信时延... 针对多智能体固定拓扑网络,考虑无时延和有时延两种情况,研究了多智能体网络的分布式编队控制协议.首先,针对无通信时延的多智能体网络,提出了分布式编队控制协议,利用Lyapunov稳定理论,给出了协议有效的充分条件.然后,考虑时变通信时延,利用Lyapunov-Krasovskii函数证明了协议的有效性.最后,利用仿真实验证明了所设计协议的有效性.本文的创新点是对二阶多智能体网络设计分布式编队控制协议时考虑了速度一致性. 展开更多
关键词 分布式编队控制 leader-following 时延 多智能体系统
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Leader-following多自主体系统时变编队跟踪控制 被引量:1
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作者 韩娜妮 赵莉 《兰州理工大学学报》 CAS 北大核心 2023年第2期88-95,共8页
考虑时变时延,研究了高阶leader-following多自主体系统的分布式时变编队跟踪控制问题.针对连续高阶多自主体系统,设计了基于观测器的时变编队跟踪控制协议,通过状态变换,将系统的时变编队跟踪控制问题,转变为误差系统的稳定性问题.然... 考虑时变时延,研究了高阶leader-following多自主体系统的分布式时变编队跟踪控制问题.针对连续高阶多自主体系统,设计了基于观测器的时变编队跟踪控制协议,通过状态变换,将系统的时变编队跟踪控制问题,转变为误差系统的稳定性问题.然后利用图论及李雅普诺夫稳定定理,研究了系统实现时变编队跟踪控制的充分条件,并且指出时变编队参考函数与时变时延无关.最后,数据仿真结果证明了所设计的协议能使follower自主体实现时变编队,并且跟踪leader自主体的轨迹. 展开更多
关键词 leader-following多自主体系统 时变编队 跟踪控制 编队参考函数
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基于观测器的多智能体网络leader-following编队控制
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作者 韩娜妮 张可儿 徐秀妮 《陇东学院学报》 2015年第1期22-25,共4页
主要研究了leader-following多智能体网络的分布式编队问题。假设多智能体网络中的每个follower不能实时得到leader的信息,针对每个follower设计相应的分布式观测器。考虑了无时延的切换拓扑多智能体网络和存在时变时延的固定网络两种... 主要研究了leader-following多智能体网络的分布式编队问题。假设多智能体网络中的每个follower不能实时得到leader的信息,针对每个follower设计相应的分布式观测器。考虑了无时延的切换拓扑多智能体网络和存在时变时延的固定网络两种情况。利用Lyapunov稳定定理,给出了系统稳定和控制协议有效的充分条件。最后,给出了数字仿真结果以验证所设计协议的有效性,即followers形成所要求的编队并且与leader达到速度一致。 展开更多
关键词 leader-following编队控制 分布式观测器 多智能体网络
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