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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 of upper eyelid after unilateral blepharoptosis repair with minimally invasive conjoint fascial sheath suspension technique
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作者 Yianzhu Liu Wenli Chen Xia Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期53-60,共8页
AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective st... AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December 2021.Inclusion criteria included unilateral mild and moderate ptosis,good levator muscle function(>9 mm)and follow-up of at least 6mo.Pre-and post-operative symmetry was graded subjectively for marginal reflex distance 1(MRD1),tarsal platform show(TPS)and eyebrow fat span(BFS).A t-test was used to evaluate MRD1,TPS and BFS asymmetry by calculating delta values.The Bézier curve tool of the Image J software was used to extract the upper eyelid contours,where the symmetry was measured by the percentage of overlapping curvatures(POC).RESULTS:Totally 105 patients(105 eyelids)were included(mild group,n=84;moderate group,n=21).Postoperatively,all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged BFS.The asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively,and it decreased to 0.58±0.67 postoperatively in all cases(P=0.0004).In patients with mild ptosis,the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38(P=0.0187).The symmetry of the upper eyelid contour increased in all subgroups of patients,with a POC of 59.39%±13.45%preoperatively and POC of 78.29%±13.80%postoperatively.CONCLUSION:Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1(all subgroups),POC(all subgroups)and TPS(only mild group),whereas BFS is unaffected. 展开更多
关键词 SYMMETRY unilateral blepharoptosis minimally invasive combined fascia sheath suspension
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Role of targeted neuromodulation in the treatment of congenital unilateral lower lip palsy:A clinical case report
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作者 Hafiz Saqib Sikandar Ali Hassan Ameer Hamza 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第3期139-141,共3页
Congenital unilateral lower lip palsy(CULLP),or congenital hypoplasia of the depressor anguli oris muscle,also known as asymmetric crying facies,is a rare condition that results in asymmetry of the lower lip during sm... Congenital unilateral lower lip palsy(CULLP),or congenital hypoplasia of the depressor anguli oris muscle,also known as asymmetric crying facies,is a rare condition that results in asymmetry of the lower lip during smiling,laughing,and crying.Although the etiology is unknown,weakness of the depressor labii inferioris(DLI)muscle is implicated as a contributing factor.Currently,no well-established treatment options are available.This case report describes an 18-year-old male patient diagnosed with CULLP.Physical examination revealed a symmetric face at rest,but asymmetry when smiling and opening the mouth.Following the administration of lidocaine into the affected DLI muscle,the patient’s smile and lower lip symmetry were immediately restored without any adverse effects.Subsequently,administration of botulinum toxin for neuromodulation of the DLI muscle led to a significant improvement in symmetry and oral function within 2 weeks,which was sustained at 1 month and 3 months post-treatment.No adverse effects were reported,and both patients and families expressed high satisfaction with the outcomes.This case highlights the potential use of neuromodulation as a minimally invasive and effective treatment for CULLP. 展开更多
关键词 Facial paralysis Botulinum toxin Chemodenervation Asymmetric smile Congenital unilateral lower lip palsy Asymmetric crying facies
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Intentionally unilateral prostatic artery embolization:Patient selection,technique and potential benefits
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作者 Hippocrates Moschouris Konstantinos Stamatiou 《World Journal of Radiology》 2024年第9期380-388,共9页
BACKGROUND Prostatic artery embolization(PAE)is a promising but also technically demanding interventional radiologic treatment for symptomatic benign prostatic hyperplasia.Many technical challenges in PAE are associat... BACKGROUND Prostatic artery embolization(PAE)is a promising but also technically demanding interventional radiologic treatment for symptomatic benign prostatic hyperplasia.Many technical challenges in PAE are associated with the complex anatomy of prostatic arteries(PAs)and with the systematic attempts to catheterize the PAs of both pelvic sides.Long procedure times and high radiation doses are often the result of these attempts and are considered significant disadvantages of PAE.The authors hypothesized that,in selected patients,these disadvantages could be mitigated by intentionally embolizing PAs of only one pelvic side.AIM To describe the authors’approach for intentionally unilateral PAE(IU-PAE)and its potential benefits.METHODS This was a single-center retrospective study of patients treated with IU-PAE during a period of 2 years.IU-PAE was applied in patients with opacification of more than half of the contralateral prostatic lobe after angiography of the ipsilateral PA(subgroup A),or with markedly asymmetric prostatic enlargement,with the dominant prostatic lobe occupying at least two thirds of the entire gland(subgroup B).All patients treated with IU-PAE also fulfilled at least one of the following criteria:Severe tortuosity or severe atheromatosis of the pelvic arteries,non-visualization,or visualization of a tiny(<1 mm)contralateral PA on preprocedural computed tomographic angiography.Intraprocedural contrast-enhanced ultrasonography(iCEUS)was applied to monitor prostatic infarction.IU-PAE patients were compared to a control group treated with bilateral PAE.RESULTS IU-PAE was performed in a total 13 patients(subgroup A,n=7;subgroup B,n=6).Dose-area product,fluoroscopy time and operation time in the IU-PAE group(9767.8μGy∙m^(2),30.3 minutes,64.0 minutes,respectively)were significantly shorter(45.4%,35.9%,45.8%respectively,P<0.01)compared to the control group.Clinical and imaging outcomes did not differ significantly between the IU-PAE group and the control group.In the 2 clinical failures of IU-PAE(both in subgroup A),the extent of prostatic infarction(demonstrated by iCEUS)was significantly smaller compared to the rest of the IU-PAE group.CONCLUSION In selected patients,IU-PAE is associated with comparable outcomes,but with lower radiation exposure and a shorter procedure compared to bilateral PAE.iCEUS could facilitate patient selection for IU-PAE. 展开更多
关键词 Prostatic artery embolization unilateral Computed tomographic angiography Dose area product Fluoroscopy time Prostatic infarction
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Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding
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作者 Thomas Lesser Frank Wolfram +1 位作者 Conny Braun Reiner Gottschall 《World Journal of Experimental Medicine》 2024年第1期88-99,共12页
BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is ... BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion. 展开更多
关键词 One-lung ventilation unilateral superimposed high-frequency jet ventilation One-lung flooding
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Study on the Design Scheme of Vehicle Flow Lines in Unilateral Agglomerative Open Service Area
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作者 Tengfei Gong 《Journal of World Architecture》 2024年第3期22-29,共8页
In recent years,with the introduction of the strategy to strengthen the country’s transportation infrastructure and the continuous implementation of new economic development models such as integrating transportation ... In recent years,with the introduction of the strategy to strengthen the country’s transportation infrastructure and the continuous implementation of new economic development models such as integrating transportation with tourism,various open service areas integrating highway service areas with local tourism have emerged nationwide.Examples include the Yangcheng Lake service area in Jiangsu and the Lengshui service area in Chongqing.This paper focuses on the design example of the Dazu Stone Carving service area on the Chongqing section of the Yurong Expressway,comprehensively considering factors such as construction scale,terrain conditions,and local urban planning.It analyzes and studies the traffic flow design of unilateral agglomerative open service areas around two vehicle traffic conversion links:between the main expressway and the service area,and between the service area and local roads.The aim is to provide a case study reference for similar projects. 展开更多
关键词 unilateral agglomeration Open service area Traffic flow line Online publication:July 11 2024
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Unilateral post-chemotherapy robot-assisted retroperitoneal lymph node dissection in Stage II non-seminomatous germ cell tumor:A tertiary care experience
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作者 Dario Franzese Antonio Tufano +11 位作者 Alessandro Izzo Raffaele Muscariello Giovanni Grimaldi Giuseppe Quarto Luigi Castaldo Sabrina Rossetti Savio Domenico Pandolfo Sonia Desicato Paola Del Prete Matteo Ferro Sandro Pignata Sisto Perdonà 《Asian Journal of Urology》 CSCD 2023年第4期440-445,共6页
Objective Post-chemotherapy retroperitoneal lymph node dissection(PC-RPLND)represents an integral component of the management of patients with non-seminomatous germ cell tumor(NSGCT).Modified templates have been propo... Objective Post-chemotherapy retroperitoneal lymph node dissection(PC-RPLND)represents an integral component of the management of patients with non-seminomatous germ cell tumor(NSGCT).Modified templates have been proposed to minimize the surgical morbidity of the procedure.Moreover,the implementation of robotic surgery in this setting has been explored.We report our experience with unilateral post-chemotherapy robot-assisted retroperitoneal lymph node dissection(PC-rRPLND)for clinical Stages IIA and IIB NSGCTs.Methods A retrospective single institution review was performed including 33 patients undergoing PC-rRPLND for Stages IIA and IIB NSGCTs between January 2015 and February 2019.Following orchiectomy,patients were scheduled for chemotherapy with three cycles of bleomycin-etoposide-cisplatin.Patients with a residual tumor of<5 cm and an ipsilateral metastatic disease on pre-and post-chemotherapy CT scans were eligible for a unilateral template in absence of rising tumor markers.Descriptive statistics were provided for demographics,clinical characteristics,intraoperative and postoperative parameters.Perioperative,oncological,and functional outcomes were recorded.Results Overall,7(21.2%)patients exhibited necrosis or fibrosis;14(42.4%)had mature teratoma;and 12(36.4%)had viable tumor at final histology.The median lymph node size at surgery was 25(interquartile range[IQR]21-36)mm.Median operative time was 180(IQR 165-215)min and no major postoperative complications were observed.Anterograde ejaculation was preserved in 75.8%of patients.Median follow-up was 26(IQR 19-30)months and a total of three recurrences were recorded.Conclusion PC-rRPLND is a reliable and technically reproducible procedure with safe oncological outcomes and acceptable postoperative ejaculatory function in well selected patients with NSGCTs. 展开更多
关键词 Testis tumor Robot-assisted retroperitoneal lymph node dissection Retroperitoneal lymph node dissection Non-seminomatous germ cell tumor unilateral dissection Modified template Post-chemotherapy
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Modified unilateral periureteral injection technique in the treatment of patients with high-grade vesicoureteral reflux: A study of primary findings
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作者 Seyed Alaeddin Asgari Afshin Safaei-Asl +5 位作者 Mandana Mansour-Ghanaie Seyed Mohammad Asgari Asghar Faryabi Mohammadreza Bazli Faezeh Emami Sigaroudi Seyed Ahmad Naseri Alavi 《Asian Journal of Urology》 CSCD 2023年第1期96-100,共5页
Objective:Although endoscopic treatment has been used by many pediatric urologists for the treatment of vesicoureteral reflux(VUR),it has no considerable success in high-grade VUR.We aimed to describe the primary outc... Objective:Although endoscopic treatment has been used by many pediatric urologists for the treatment of vesicoureteral reflux(VUR),it has no considerable success in high-grade VUR.We aimed to describe the primary outcomes of unilateral periureteral injection technique(PIT),as well as bilateral PIT in high-grade VUR.Methods:In this prospective study,we examined 92 ureters in 45 boys and 40 girls from February 2010 to May 2018.Bilateral PIT and unilateral PIT were applied in 67 and 25 refluxing units,respectively.In the unilateral PIT,the subureteral injection site was only at the 5-or 7-o’clock position.However,in the bilateral PIT,the subureteral injection sites were at 5-and 7-o’clock position.Pre-and post-operative reflux grades were evaluated by voiding cystourethrography 6 months after surgery.Results:Seven patients had bilateral reflux.Overall,75(81.5%)ureters showed Grade IV VUR,while 17(18.5%)had primary Grade V VUR.The mean age of the subjects was 39.2 months.In unilateral PIT ureters,VUR was resolved in 23(92.0%)refluxing units.It was downgraded to Grade III in one ureter(4.0%)and to Grade II in another ureter(4.0%).In addition,in bilateral PIT cases,VUR was resolved in 60(89.6%)ureters;it downgraded to Grades II and III in 3(4.5%)and 4(6.0%)refluxing units,respectively.Conclusion:Unilateral PIT can be highly effective in the treatment of selected ureters of high-grade VUR.However,further studies are needed to confirm our results. 展开更多
关键词 Periureteral injection technique Bilateral periureteral injection technique unilateral periureteral injection technique ENDOSCOPY Vesicoureteral reflux
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Recurrence of unilateral angioedema of the tongue:A case report
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作者 Yuki Matsuhisa Tsuneaki Kenzaka +2 位作者 Hironori Shimizu Hideo Hirose Tadao Gotoh 《World Journal of Clinical Cases》 SCIE 2023年第27期6603-6612,共10页
BACKGROUND Angioedema is a disorder characterized by edema of the face,lips,tongue,and extremities due to increased vascular permeability.Angioedema of the tongue usually occurs bilaterally,and the incidence of unilat... BACKGROUND Angioedema is a disorder characterized by edema of the face,lips,tongue,and extremities due to increased vascular permeability.Angioedema of the tongue usually occurs bilaterally,and the incidence of unilateral angioedema of the tongue is rare.This study reports a rare case of unilateral angioedema of the tongue with no identifiable cause and repeated recurrence even after discontinuation of an angiotensin-converting enzyme inhibitor.CASE SUMMARY The patient was a 65-year-old woman with pre-existing hypertension and hyperlipidemia and had been receiving 20 mg/d of lisinopril.She was diagnosed with angioedema due to unilateral swelling of the tongue.No airway obstruction was observed,and the symptoms improved following the administration of 0.3 mg of epinephrine intramuscularly and 125 mg of methylprednisolone intravenously.Although lisinopril was discontinued,unilateral angioedema of the tongue continued to recur every 2-5 mo,with the symptoms improving following the administration of prednisolone and an antihistamine.Daily oral administration of 500 mg of tranexamic acid after dinner prevented the recurrence of angioedema.CONCLUSION Careful monitoring and identification of the underlying mechanism play a crucial role in the treatment of angioedema. 展开更多
关键词 ANGIOEDEMA TONGUE unilateral BRADYKININ Tranexamic acid Case report
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Clinical Study on Treatment of Type II/III Lumbar Brucellar Spondylitis by Unilateral Biportal Endoscopy
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作者 Xinming Yang Yongli Jia +2 位作者 Fei Liu Zhe Zhang Peinan Zhang 《Surgical Science》 2023年第5期321-330,共10页
Objective: Explore the feasibility and clinical efficacy of using unilateral biportal endoscopy for the treatment of Type II/III lumbar brucellar spondylitis. Methods: A retrospective study of the clinical data of 20 ... Objective: Explore the feasibility and clinical efficacy of using unilateral biportal endoscopy for the treatment of Type II/III lumbar brucellar spondylitis. Methods: A retrospective study of the clinical data of 20 patients with Type II/III lumbar brucellar spondylitis admitted to the First Affiliated Hospital of Hebei North University from January 2020 to May 2022, including 15 males and 5 females, aged 41 - 60 years old, average age (48.11 ± 7.28) years old. After admission, the patient can isolate brucella through metagenomic Next-Generation Sequencing (mNGS), meeting the tertiary diagnostic criteria. Preoperative conventional drug treatment, unilateral biportal endoscopic minimally invasive surgery was performed when nutrition was improved, perioperative control of various indexes was stable, and erythrocyte sedimentation was declining. It was completed under an endoscope. The lesion was cleared, spinal nerve compression was relieved, interbody fusion was performed, and the spine was fixed by a percutaneous pedicle screw. Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP), Visual Analogue Scale (VAS), Japanese Orthopedic Association (JOA) score and Oswestry Disability Index (ODI) were analyzed at 1 month, 3 months, 6 months and the last follow-up. At the final follow-up of all patients, the clinical efficacy criteria and the Bridwell grading criteria were used to evaluate the recovery and intervertebral bone graft fusion, respectively. Results: All patients’ lower back and leg pain was relieved the next day after surgery. At a follow-up of one month after surgery, both systemic and local symptoms significantly improved. At the last follow-up, clinical symptoms disappeared and there was no tenderness or percussion pain in the local area. With the passage of time, 1 month, 3 months, 6 months after the operation, and the last follow-up are all evaluation indicators compared with those before the operation. No matter VAS, JOA, ODI score, or ESR, CRP is significantly improved compared with preoperative (P All 20 cases in this group reached the BS clinical cure standard, and the excellent rate of intervertebral bone graft fusion was 95%. Conclusion: On the basis of . 展开更多
关键词 Brucellar Spondylitis Minimally Invasive Surgery unilateral Biportal Endoscopy Clinical Efficacy
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Symmetry and Hojman Conserved Quantity of Tznoff 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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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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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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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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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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