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Effect of stimulating acupoint Guanyuan(CV 4) on lower back pain by burning moxa heat for different time lengths: a randomized controlled clinical trial 被引量:13
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作者 Xu Jianfeng Lin Ruizhu +7 位作者 Wu Yongli Wang Yingxu Liu Jian Zhang Yanling Zhang Yuequan Xi Chaolei Wu Qiang Li Xinjian 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第1期36-40,共5页
OBJECTIVE: To investigate the effect of different heat-stimulating time lengths on lower back pain.METHODS: Forty participants were randomly assigned to four groups of various heating time lengths. The short heating t... OBJECTIVE: To investigate the effect of different heat-stimulating time lengths on lower back pain.METHODS: Forty participants were randomly assigned to four groups of various heating time lengths. The short heating time length group(SL),moderate heating time length group(ML), and long heating time length group(LL) respectively received 15, 30, and 60 min of moxibustion therapy stimulating the acupoint Guanyuan(CV 4). The conventional acupuncture group(CA) received needle acupuncture treatment as a control group. The participants were treated continuously over a 2-week treatment period for a total of 10 sessions, with five sessions given per week. Participants were assessed weekly by blinded assessors, using the visual analogue scale(VAS) and Roland Morris Questionnaire(RMQ).RESULTS: The VAS and RMQ scores reduced in all four groups during treatment. There were significant differences in VAS scores(P < 0.01) and RMQ scores(P < 0.01) between before treatment and after 2 weeks of treatment in the LL group. After treatment, the LL group reported significantly lower VAS scores compared with the CA group, ML group,and SL group(P < 0.05).CONCLUSION: The long and moderate lengths of heat-stimulating time of 30 and 60 min may be more effective for relieving lower back pain than that of short stimulating time lengths. 展开更多
关键词 Moxibustion Burning moxa Heatingtime length Acupuncture lower back pain Guanyuan (CV 4) Randomized controlled trials
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Chondroid syringoma of the lower back simulating lipoma:A case report
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作者 Qiu-Feng Huang Bo Yu +1 位作者 Xiao-Ping Hu Yong Shao 《World Journal of Clinical Cases》 SCIE 2022年第29期10708-10712,共5页
BACKGROUND Chondroid syringoma(CS)is a rare tumor of the apocrine or eccrine glands.CS of the lower back is rare,and its clinical manifestations are similar to those of lipoma,which is a common misdiagnosis for this d... BACKGROUND Chondroid syringoma(CS)is a rare tumor of the apocrine or eccrine glands.CS of the lower back is rare,and its clinical manifestations are similar to those of lipoma,which is a common misdiagnosis for this disease.CASE SUMMARY A 39-year-old woman presented with a 2-year history of an asymptomatic subcutaneous mass on the lower back.The lesions increased progressively over time.The patient denied any history.Dermatological examination showed that there was a subcutaneous mass,ranging from 3-4 cm in diameter,with a clear boundary on the lower back.The surface of the skin was smooth without ulceration or scaling.Histopathologic examination was consistent with the diagnosis of CS.CONCLUSION CS is a rare tumor of the apocrine or eccrine glands.It usually presents as a wellcircumscribed and single subcutaneous masses.Histopathology showed the tumor was located in the dermis,with nests,sheets,and cords of basal-like cells,mucin deposition,and chondroid structures.We herein report a case of CS located in the lower back.CS of the lower back is rare,and its clinical manifestations are similar to those of lipoma,for which it is commonly misdiagnosed. 展开更多
关键词 Chondroid syringoma Mixed tumor lower back LIPOMA Case report
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Protocol for lower back pain management: Insights from the French healthcare system
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作者 Lea Evangeline Boyer Mathieu Boudier-Revéret Min Cheol Chang 《World Journal of Clinical Cases》 SCIE 2024年第11期1875-1880,共6页
In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with ... In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with lateral recess stenosis.The impact of spinal pain-related disability extends significantly,causing substantial human suffering and medical costs.Each county has its preferred treatment strategies for spinal pain.Here,we explore the lower back pain(LBP)treatment algorithm recommended in France.The treatment algorithm for LBP recommended by the French National Authority for Health emphasizes early patient activity and minimal medication use.It encourages the continuation of daily activities,limits excessive medication and spinal injections,and incorporates psychological assessments and non-pharmacological therapies for chronic cases.However,the algorithm may not aggressively address acute pain in the early stages,potentially delaying relief and increasing the risk of chronicity.Additionally,the recommended infiltrations primarily involve caudal epidural steroid injections,with limited consideration for other injection procedures,such as transforaminal or interlaminar epidural steroid injections.The fixed follow-up timeline may not accommodate patients who do not respond to initial treatment or experience intense pain,potentially delaying the exploration of alternative therapies.Despite these limitations,understanding the strengths and weaknesses of the French approach could inform adaptations in LBP treatment strategies globally,potentially enhancing patient outcomes and satisfaction across diverse healthcare systems. 展开更多
关键词 lower back pain PROTOCOL FRANCE TREATMENT Chronic pain
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Lower Back Pain and Forearm Tendinitis Linked to Irritation of Oral Mucosa by Teeth
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作者 Sanae Miyaji 《Case Reports in Clinical Medicine》 2020年第9期295-302,共8页
We present a case of a woman with refractory lower back pain and forearm tendinitis, which improved dramatically after morphological modification of natural teeth. The subject was a 35-year-old Japanese woman, who was... We present a case of a woman with refractory lower back pain and forearm tendinitis, which improved dramatically after morphological modification of natural teeth. The subject was a 35-year-old Japanese woman, who was suffering from lower back pain when bending forward and she had severe pain from her right thumb to her wrist. These symptoms were not improved by massage and orthopedic treatment. On the other hand, once modifying the morphology of natural teeth, those symptoms improved dramatically. No side effects were observed, and the prognosis was good. Our observation suggested a close relationship between the oral situation and remote musculoskeletal conditions, and further multidisciplinary studies are needed to clarify the mechanisms. 展开更多
关键词 lower back Pain Forearm Tendinitis Dental Treatment Systemic Symptoms The Bi-Digital O-Ring Test
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Treatment of 1480 cases of prolapse of lower back intervertebral disc with massage
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作者 谷万里 张梅红 栾光法 《中国组织工程研究与临床康复》 CAS CSCD 2001年第24期143-144,共1页
关键词 Treatment of 1480 cases of prolapse of lower back intervertebral disc with massage
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To analyse the effects of massage on severe prolapse of intervertebral discs of the lower back
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作者 李加斌 《中国组织工程研究与临床康复》 CAS CSCD 2001年第24期145-,共1页
关键词 To analyse the effects of massage on severe prolapse of intervertebral discs of the lower back
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An Exercise Rehabilitative Solution to Work-Related Musculoskeletal Lower Back Pain among Nurses
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作者 Yvonne Paul Terry J. Ellapen +4 位作者 Mariette Swanepoel Henriette V. Hammill Henriette V. Hammill Marco Barnard Bongani T. Qumbu 《Open Journal of Orthopedics》 2018年第8期322-330,共9页
The attrition of professional nurses is a sad reality. Work-related musculoskeletal lower back pain (WRMLBP) among nurses has been cited as a factor of increased sick leave and poor health. Occupational predisposing f... The attrition of professional nurses is a sad reality. Work-related musculoskeletal lower back pain (WRMLBP) among nurses has been cited as a factor of increased sick leave and poor health. Occupational predisposing factors of lower back pain are strenuous physical stresses of nursing, obesity and poor physical conditioning. Regular stretching and strengthening exercises dissipate lower back pain. This commentary’s objectives are to explain the association between obesity and lower back pain and the exercise mechanism that dissipates this pain, thereby concluding that nurses should consider regular exercise as a therapeutic option. 展开更多
关键词 Nurses lower back PAIN EXERCISE
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Lower Bound of Distance Between Unitary Orbits of Normal Elements in C^(*)-algebras of Tracial Rank One
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作者 WANG Ruofei LUO Zheng 《数学进展》 北大核心 2026年第1期171-182,共12页
This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial ra... This paper studies certain estimates for the lower bound of distance between unitary orbits of normal elements.We show that the distance between unitary orbits of normal elements of simple C^(*)-algebras of tracial rank no more than k has a lower bound.Furthermore,if k≤1 and normal elements are commuting,then the lower bound will be better.Another result establishes a connection involving the spectrum distance operator Dc between a C^(*)-algebra of stable rank one C^(*)-algebra and its hereditary C^(*)-subalgebra. 展开更多
关键词 unitary orbit hereditary C^(*)-subalgebra tracial rank one lower bound
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Petrographic,Mineralogical and Geochemical Constraints on the Origin of Regional-Scale Dolomitization:A Case Study of the Cambrian–Lower Ordovician Dolomites in the Bachu Area,Central Tarim Basin,China
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作者 Miao Li Yushuang Zhou +3 位作者 Yongqiang Zhao Juan Xu Fei Wu Feng Geng 《Journal of Earth Science》 2026年第1期23-35,共13页
The Cambrian and Lower Ordovician strata of the Bachu area in central Tarim Basin are characterized by extensively dolomitized,which have significant potential for favourable hydrocarbon reservoirs.The study herein co... The Cambrian and Lower Ordovician strata of the Bachu area in central Tarim Basin are characterized by extensively dolomitized,which have significant potential for favourable hydrocarbon reservoirs.The study herein combined petrographic,mineralogical and geochemical analyses to investigate the formation environments of these dolomite units and utilized Mg isotopic profiles to constrain the changes in the fluid flow trajectory.Positive excursions of δ^(18)O and upwardincreasing δ^(26)Mg profiles were observed in samples of the Wusonger formation(Є_(1)w),which may result from evaporation.Moreover,based on high ^(87)Sr/^(86)Sr ratios,high total REE concentrations and the occurrence of specific minerals,including quartz,barite,gypsum and pyrite,we interpret an evaporitic near-surface origin for the Є_(1)w dolomites.Samples of the Xiaoerblak Formation(Є_(1)x)are the product of seepage-reflux dolomitization,suggested by upward-decreasing δ^(26)Mg profiles and relatively lower ^(87)Sr/^(86)Sr ratios than the Є_(1)w samples.The overlapping isotope(δ^(18)O,δ^(13)C and ^(87)Sr/^(86)Sr)values between samples of the Shayilik(Є_(2)s)and Awatagh(Є_(2)a)Formation,in addition to the petrography evidence and Mg isotope variations,suggest that the formation of these dolomites were due to the shallow-burial dolomitization.The occurrence of the Xiaqiulitagh(Є_(3)ql)and Penglaiba(O_(1)p)dolomites along stylolites,together with their large crystals with opaque cores and clear rims and vertically constant δ^(26)Mg profiles,indicate that their formation may be related to pressure dissolution by mechanical compaction during deep-burial dolomitization.Therefore,the assembling of multiple petrographic,mineralogical and geochemical methods can shed light on the complicated generation processes of regional-scale dolomite within Tarim Basin or elsewhere. 展开更多
关键词 genesis of dolomites ISOTOPES magnesium isotope Tarim Basin Cambrian–lower Ordovician
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Effect of neurodynamic mobilization on lower limb function in patients with mild post-traumatic knee osteoarthritis
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作者 Jun-Rong Hu Meng-Xiao He +4 位作者 Shan-Shan Wei Han-Wen Ren Cheng-Hao Liu Xiao-Long Liu Zhen-Cheng Chen 《World Journal of Orthopedics》 2026年第1期106-118,共13页
BACKGROUND The therapeutic role of neurodynamic mobilization in improving lower limb function in patients with mild post-traumatic knee osteoarthritis remains poorly understood.AIM To further elucidate the role of neu... BACKGROUND The therapeutic role of neurodynamic mobilization in improving lower limb function in patients with mild post-traumatic knee osteoarthritis remains poorly understood.AIM To further elucidate the role of neurodynamic mobilization in facilitating knee joint functional recovery.METHODS Thirty-two patients with post-traumatic knee osteoarthritis treated at Chonghua Hospital of Traditional Chinese Medicine(Guilin)from March 2024 to August 2025 were randomly assigned to a control group(n=16)or an intervention group(n=16).Both groups received eight weeks of conventional treatment;and the intervention group additionally underwent neurodynamic mobilization.Outcomes including pain assessed by the visual analogue scale,active range of motion,Lysholm score,stork stand test,single hop test,and Y-balance test were assessed before and after the intervention.RESULTS There were no significant differences between the two groups in baseline characteristics,including gender,age,body mass index,or surgical side(P>0.05).Two-way repeated-measures analysis of variance demonstrated significant time×group interaction effects for the visual analogue scale score(F=13.364,P<0.05),Lysholm knee score(F=20.385,P<0.05),stork stand test(F=103.756,P<0.05),and Y-balance test score(F=8.089,P<0.05).CONCLUSION Neurodynamic mobilization effectively reduces pain,improves knee function,and enhances lower limb balance in patients with mild post-traumatic knee osteoarthritis. 展开更多
关键词 Mild post-traumatic knee osteoarthritis Neurodynamic mobilization lower limb function Randomized controlled trial REHABILITATION
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Feasibility of water vapor thermal therapy for treating lower urinary tract symptoms in men with localized prostate cancer on active surveillance:a case series
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作者 Mustufa Babar Farooz Babar +2 位作者 Noah Hawks-Ladds Justin Loloi Michael Ciatto 《The Canadian Journal of Urology》 2026年第1期193-199,共7页
Background:Prostate cancer is a common malignancy,with many men on active surveillance for localized,low-risk disease also experiencing lower urinary tract symptoms(LUTS)from benign prostatic hyperplasia(BPH).Water Va... Background:Prostate cancer is a common malignancy,with many men on active surveillance for localized,low-risk disease also experiencing lower urinary tract symptoms(LUTS)from benign prostatic hyperplasia(BPH).Water Vapor Thermal Therapy(WVTT)is a minimally invasive BPH treatment,but its safety and efficacy in this setting are unclear.Case Description:We report three men with localized PCa on active surveillance who underwent WVTT for LUTS.Conclusions:WVTT appears safe and potentially effective in treating LUTS,especially in those with lower-risk disease and smaller prostate volumes.Further research is needed to confirm safety,efficacy,and optimal patient selection. 展开更多
关键词 lower urinary tract symptoms benign prostatic hyperplasia prostatic neoplasms active surveillance case report
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Classification Method of Lower Limbs Motor Imagery Based on Functional Connectivity and Graph Convolutional Network
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作者 Yang Liu Qi Lu +2 位作者 Junjie Wu Huaichang Yin Shiwei Cheng 《Computers, Materials & Continua》 2026年第3期1674-1689,共16页
The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied... The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied in many fields,including rehabilitation.However,the physiological representations of left and right lower limb movements are too close and activated deep in the cerebral cortex,making it difficult to distinguish their features.Therefore,classifying lower limbs motor imagery is more challenging.In this study,we propose a feature extraction method based on functional connectivity,which utilizes phase-locked values to construct a functional connectivity matrix as the features of the left and right legs,which can effectively avoid the problem of physiological representations of the left and right lower limbs being too close to each other during movement.In addition,considering the topology and the temporal characteristics of the electroencephalogram(EEG),we designed a temporal-spatial convolutional network(TSGCN)to capture the spatiotemporal information for classification.Experimental results show that the accuracy of the proposed method is higher than that of existing methods,achieving an average classification accuracy of 73.58%on the internal dataset.Finally,this study explains the network mechanism of left and right foot MI from the perspective of graph theoretic features and demonstrates the feasibility of decoding lower limb MI. 展开更多
关键词 Brain-computer interface lower limb motor imagery functional connectivity temporal-spatial convolutional network
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Study on the Role of Weak Lower Crust in Cenozoic Tectonic Deformation of Qinghai-Tibet Plateau by an Integrated Centrifugal Analog Modeling and Numerical Simulation Approach
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作者 Xiang Chen Duanyang Zhuang +7 位作者 Liangtong Zhan Wenjie Xu Jinlong Li Linbo Wu Haibin Yang Jisen Shi Zizhuang Yan Yunmin Chen 《Journal of Earth Science》 2026年第1期137-154,共18页
The India-Asia collision resulted in the formation of Qinghai-Tibet Plateau.Lower crustal flow model was proposed to explain the mechanism of Cenozoic tectonic deformation of Qinghai-Tibet Plateau.In this study,we pro... The India-Asia collision resulted in the formation of Qinghai-Tibet Plateau.Lower crustal flow model was proposed to explain the mechanism of Cenozoic tectonic deformation of Qinghai-Tibet Plateau.In this study,we propose a new approach by combining centrifugal analog modeling with numerical simulation to simulate the tectonic uplift history of the plateau based on the lower crustal flow model,and to investigate the material migration characteristics and the influence of crustal motion velocity and ductile layer viscosity on the plateau tectonic geomorphology.The models reproduce steep-sided flat-topped geomorphic features and clockwise rotation of the material at eastern Himalayan Syntaxis,verifying the rationality of the models.The results show that the greater the crustal motion velocity and the greater the ductile layer viscosity,the steeper the terrain change;and conversely,the smaller the crustal motion velocity and the smaller the ductile layer viscosity,the gentler the terrain change.This study further indicates that the weak lower crust plays an important role in the formation of geomorphic features and material migration characteristics of Qinghai-Tibet Plateau,and provides a new insight for the study of the uplift mechanism of the Tibetan Plateau. 展开更多
关键词 Qinghai-Tibet Plateau lower crustal flow model centrifugal analog modeling numerical simulation geomorphic features material migration
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Deep Learning in Electromyography Signal-based Lower Limb Angle Prediction and Activity Classification
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作者 Gundala Jhansi Rani Mohammad Farukh Hashmi 《Journal of Bionic Engineering》 2026年第1期274-290,共17页
This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamline... This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamlines the research on the lower limb activities.The HILLAR model includes Discrete Hermite Wavelets Transform-based Synchrosqueezing(DHWTS),Deep Two-Layer Multiscale Convolutional Neural Network(DTLMCNN),and Generalized Regression Neural Network(GRNN)as feature extraction,activity recognition,and knee angle prediction respectively.Electromyography signal-based automatic lower limb activity detection is crucial to rehabilitation and human movement analysis.Yet several of these methods face issues in feature extraction in complex data,overlapping signals,extraction of crucial parameters,and adaptation constraints.This research aims classify lower limb activities and predict knee joint angles from electromy-ography signals using HILLAR model.The model is validated on two datasets,comprising 26 subjects performing three classes of activities:walking,standing,and sitting.The proposed model obtained a classification accuracy of 99.95%,along with significant achievements in precision(99.93%),recall(99.91%),and F1-score(99.93%).The generalized regression neural network predicted angles of the knee joint with a root mean squared error of 1.25%.Robustness is demonstrated through consistent results in five-fold cross-validation and statistical significance testing(p-value=0.004,McNemar's test).Additionally,the proposed model showed superior performance over baseline methods by reducing error rates by 18%and decreasing processing time to 0.98 s. 展开更多
关键词 ELECTROMYOGRAPHY lower limb motion recognition Knee joint angle prediction Convolutional neural network Wavelet transform
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Clinical Efficacy of Periosteum-Preserving Iliac Crest Transverse Transport for Symptomatic High-Level Lower Extremity Arteriosclerosis Obliterans
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作者 Guangchen Nie Xiangyue Meng +7 位作者 Yong Liu Xuguang Hao Yang Liu Shouyang Xiang Yongxin Huo Long Jiang Qiang Xu Yicun Lu 《Chronic Diseases and Translational Medicine》 2026年第1期69-72,共4页
Summary What''s New?:This study introduces a novel,periosteum-preserving iliac crest transverse transport(ICTT)technique for high-level lower extremity arteriosclerosis obliterans(LEASO),targeting patients uns... Summary What''s New?:This study introduces a novel,periosteum-preserving iliac crest transverse transport(ICTT)technique for high-level lower extremity arteriosclerosis obliterans(LEASO),targeting patients unsuitable for conventional revascularization.Technical Innovation:By relocating the osteotomy from the weight-bearing tibia to the non-weight-bearing ilium,this minimally invasive technique eliminates the risk of stress fractures,allows for immediate full weight-bearing,and expands indications to patients with proximal arterial occlusions. 展开更多
关键词 iliac crest conventional revascularizationtechnical transverse transport high level lower extremity arteriosclerosis obliterans minimally invasive technique periosteum preserving stress fractures immediate full weight bearing
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What a pain in the back:etiology,diagnosis and future treatment directions for discogenic low back pain
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作者 Giselle Kaneda Lea Zila +7 位作者 Jacob T.Wechsler Karim Shafi Karandeep Cheema Hyun Bae Sang D。Kim Alexander Tuchman Debiao Li Dmitriy Sheyn 《Bone Research》 2025年第5期1083-1110,共28页
Chronic lower back pain(LBP)is the leading cause of disability worldwide.Due to its close relationship with intervertebral disc(IVD)degeneration(IVDD),research has historically focused more on understanding the mechan... Chronic lower back pain(LBP)is the leading cause of disability worldwide.Due to its close relationship with intervertebral disc(IVD)degeneration(IVDD),research has historically focused more on understanding the mechanism behind IVDD while clinical efforts prioritize pain management.More recently,there has been a shift toward understanding LBP as a distinct pathological entity.This review synthesizes current knowledge on discogenic LBP,combining known pathophysiology,molecular mechanisms,risk factors,diagnostic challenges,and available experimental models.IVDD is a complex,multifactorial process involving biochemical,mechanical,and inflammatory changes within the disc,leading to structural breakdown and potential discogenic pain.Key mechanisms include extracellular matrix degradation,upregulation of inflammatory mediators,immune cell infiltration,and aberrant nerve and vascular ingrowth.However,not all cases of IVDD result in LBP,highlighting the need for further investigation into the cellular,molecular,and biomechanical factors contributing to symptom development.Current diagnostic tools and experimental models for studying discogenic LBP remain limited,impeding the development of targeted treatments.Existing therapies primarily focus on symptom management rather than addressing underlying disease mechanisms. 展开更多
关键词 intervertebral disc degeneration molecular mechanisms risk factors diagnostic challenges experimental models PATHOPHYSIOLOGY chronic lower back pain lbp discogenic low back pain
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Sedimentation in a Continental High-Frequency Oscillatory Lake in an Arid Climatic Background:A Case Study of the Lower Eocene in the Dongying Depression,China 被引量:2
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作者 Jie Liu Jian Wang +1 位作者 Yingchang Cao Guoqi Song 《Journal of Earth Science》 SCIE CAS CSCD 2017年第4期628-644,共17页
The sedimentary environment, formation conditions, sedimentary characteristics and the basin evolution model of high-frequency oscillatory lake in arid climatic background of the Lower Eocene in the Dongying depressio... The sedimentary environment, formation conditions, sedimentary characteristics and the basin evolution model of high-frequency oscillatory lake in arid climatic background of the Lower Eocene in the Dongying depression were studied through the analysis of drilling cores, sporepollen, geochemistry and geophysics data. During the sedimentary period of the Eocene Ek^3-Es^4x formations, because of the frequent alternation between dry and wet climates in the arid climatic background and the gentle paleo- geomorphology, the lake level and salinity of the Early Eocene Dongying depression frequently and rap- idly increased and decreased, which is referred to as a high-frequency oscillatory lake. The sedimentation and distribution of sediments in this high-frequency oscillatory lake basin were controlled by the fre- quently alternating dry-wet climates. During periods with relatively wet climate, the seasonal floods and unstable rivers led to the formation of over-flooding lake deltas in the gentle slope belt, and fine-grained clastic sediments, with minor thin layers of gypsum-salt rocks in the sag belt. During the relatively arid climatic periods, sedimentation occurred mainly in the limited area of the sag belt with thick gypsum-salt rocks. Because of the impact of the salinity stratification of the lake water, these gypsum-salt rocks exhibit annular structural features. A sedimentary cycle of the oscillatory lake began with isochronous flood channels and ended with relatively thick gypsum rocks and salt rocks. The thickness of one oscillatory cy- cle is generally 4-20 m. The superposition of multiple sedimentary cycles of the oscillatory lake constitutes the overall vertical idling sequence of the high-frequency oscillatory lake basin. 展开更多
关键词 oscillatory lake clastic sedimentation chemical sedimentation paleocfimate Dongyingdepression lower Eocene.
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Model Parameters Identification and Backstepping Control of Lower Limb Exoskeleton Based on Enhanced Whale Algorithm 被引量:1
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作者 Yan Shi Jiange Kou +2 位作者 Zhenlei Chen Yixuan Wang Qing Guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期100-114,共15页
Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction condition.However,due to unknown model parameters such as the mass,moment of i... Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction condition.However,due to unknown model parameters such as the mass,moment of inertia and mechanical size,the dynamic model of exoskeletons is difficult to construct.Hence,an enhanced whale optimization algorithm(EWOA)is proposed to identify the exoskeleton model parameters.Meanwhile,the periodic excitation trajectories are designed by finite Fourier series to input the desired position demand of exoskeletons with mechanical physical constraints.Then a backstepping controller based on the identified model is adopted to improve the human-robot wearable comfortable performance under cooperative motion.Finally,the proposed Model parameters identification and control are verified by a two-DOF exoskeletons platform.The knee joint motion achieves a steady-state response after 0.5 s.Meanwhile,the position error of hip joint response is less than 0.03 rad after 0.9 s.In addition,the steady-state human-robot interaction torque of the two joints is constrained within 15 N·m.This research proposes a whale optimization algorithm to optimize the excitation trajectory and identify model parameters.Furthermore,an enhanced mutation strategy is adopted to avoid whale evolution’s unsatisfactory local optimal value. 展开更多
关键词 Parameter identification Enhanced whale optimization algorithm(EWOA) backSTEPPING Human-robot interaction lower limb exoskeleton
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze River and neighbouring areas
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Kinematics ofmandibular advancement devices(MADs):Why do some MADs move the lower jaw backward duringmouth opening?
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作者 Juan A.Cabrera Alex Bataller +1 位作者 Sergio Postigo Marcos García 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期637-650,共14页
Mandibular advancement devices(MADs)are widely used treatments for obstructive sleep apnea.MADs function by advancing the lower jaw to open the upper airway.To increase patient comfort,most patients allow the mouth to... Mandibular advancement devices(MADs)are widely used treatments for obstructive sleep apnea.MADs function by advancing the lower jaw to open the upper airway.To increase patient comfort,most patients allow the mouth to be opened.However,not all systems maintain the lower jaw in a forward position during mouth opening,which results in the production of a retrusion that favors the collapse of the upper airway.Furthermore,the kinematic behavior of the mechanism formed by the mandible-device assembly depends on jaw morphology.This means that,during mouth opening,some devices cause lower jaw protrusion in some patients,but cause its retraction in others.In this study,we report the behavior of well-known devices currently on themarket.To do so,we developed a kinematic model of the lower jawdevice assembly.Thismodelwas validated for all devices analyzed using a high-resolution camera system.Our results show that some of the devices analyzed here did not produce the correct behavior during patient mouth opening. 展开更多
关键词 Mandibular advancement devices lower jaw kinematics Sleep apnea
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