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颈椎间盘退变的形态学观察和生物力学研究 总被引:5,自引:0,他引:5
目的:观察长时间异常应力环境下兔颈椎间盘的组织形态和生物力学性能变化,为防治颈椎病的研究提供实验依据.方法:选取30只家兔,随机分为对照组、模型组,造模家兔颈椎处于低头屈曲45°位异常应力环境下5小时/次·天.动物处死后,光镜和电镜下观察颈椎间盘组织形态学变化;功能节段生物力学性能测试.比较各组间存在的差异.结果:对照组颈椎间盘组织形态及生物力学性能无明显变化;模型组颈椎间盘发生软骨细胞变性、坏死,髓核皱缩,软骨终板钙化、断裂等组织形态学改变;椎间盘压缩、扭转生物力学性能下降,并随着异常应力作用时间的延长而表现更为显著.结论:长时间处于异常应力环境下能使兔颈椎间盘组织形态和生物力学性能均发生明显退行性改变. 相似文献
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椎间盘退变的腰椎活动节段力学模型 总被引:1,自引:0,他引:1
椎间盘是人体组织中最早发生退行性改变的部位。本文报告采用三维有限元方法建立的椎间盘退变腰椎活动节段的力学模型,着重分析其在直立时的应力分布与载荷传递情况。模型共有388个节点,组成293个单元,所得结构较为合理可靠。作者认为,本模型具有其独特的优点。可望用于进一步的研究。 相似文献
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在动物模型上研究股骨颈骨折后髋关节软骨退变在发生、发展、转归过程中软骨厚度和生物力学特性改变及其与伤后时间的关系。用新西兰白兔60只作股骨颈基底截骨制作骨折动物模型,于术后2、4、6、8、12、16周采用压凹法测定关节软骨厚度和生物力学特性。免股骨颈骨折后关节软骨持续增厚,6周达高峰,随后软骨迅速磨损、变薄;骨折后4周起软骨退变失代偿,弹性和机械强度进行性大幅度下降,退变至骨关节炎。股骨颈骨折后保守治疗形成局部低应力环境,关节软骨缺乏动态载荷,基质胶原网络迅速降解所引起的生物力学特性降低是导致并维持软骨退变不断前进的动力。 相似文献
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目前前路颈椎减压融合术(ACDF)已经广泛地应用于治疗神经根病和脊髓性颈椎病,生物力学研究发现行脊柱融合术后。手术临近节段退变加速。一些学者考虑该现象可能是由于融合术后导致临近关节活动度丢失造成,长期临床对比研究也发现颈椎间盘置换术与前路颈椎减压融合术相比,能够改善患者的临床症状。通过回顾国内外颈椎间盘置换术和关节成形术的研究进展,表明颈椎间盘置换术是一种新型的技术。与传统的融合术相比较,它具有保留节段活动度、改善临近节段载荷传递的目的。目前椎间盘置换的初步临床结果十分令人满意。 相似文献
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目的探讨葛根素对大鼠退变颈椎间盘中MMP-3和TGF-β1的影响。结论将SD雄性大鼠随机分成假手术组(A组)、模型组(B组)、葛根素高(C组)、中(D组)、低组(E组)、颈复康颗粒组(F组),每组各28只(4周组14只,8周组14只)。建立动静力失衡性大鼠颈椎间盘退变模型,分别在给药4周、8周后每组取6只标本HE组织学染色观察椎间盘的退变特征,其余8只取标本检测各组退变椎间盘中基质金属蛋白酶-3(matrix metalloproteinase-3,MMP-3)、转化生长因子-β1(transforming growth factorβ1,TGF-β1)含量。结果与A组比较,B组大鼠颈椎间盘出现明显退行性改变,大鼠颈椎间盘中TGF-β1含量减少(P〈0.05)、MMP-3含量增多(P〈0.05)。与B比较,C、D、E、F组大鼠颈椎间盘退变不明显,大鼠颈椎间盘中TGF-β1含量增多(P〈0.05)、MMP-3含量减少(P〈0.05)。结论葛根素可能通过调节细胞因子TGF-β1和MMP-3的含量,从而影响椎间盘细胞外基质合成和降解,延缓椎间盘退变。 相似文献
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机械应力异常与关节软骨退变 总被引:4,自引:0,他引:4
虽然关节软骨在组成及形态结构上有良好的力学适应性,但超生理限度的异常机械应力仍可导致关节软骨形态及功能异常,诱发关节软骨退变,异常机械应力的作用机理尚不清楚,细胞微环境改变,自身免疫反应等作用可能参与也软骨退变的病程。 相似文献
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目的 分析不同手术方式对脊髓型或/和神经根型颈椎病合并眩晕患者的治疗效果。 方法 回顾性分析62例脊髓型或/和神经根型颈椎病合并眩晕的患者,其中34例行颈后路单开门椎板减压成形术(LAM组),28例行颈前路椎间盘切除植骨融合术(ACDF组),采用美国耳鼻咽喉头颈外科学会听力及平衡委员会(CHE)标准,记录患者手术前后评分,分析两种手术方式对颈性眩晕的改善情况,比较不同病变节段颈性眩晕的发生率。 结果 LAM组中,32例术后眩晕症状明显改善,其中25例症状完全消失;2例症状无明显缓解,眩晕症状缓解率94.11%。ACDF组中,27例术后眩晕症状明显改善,其中25例症状完全消失;1例症状无明显改善,眩晕症状缓解率96.42%。在ACDF组患者中,间盘退变发生在C3/4,C4/5,C5/6,C6/7不同节段,眩晕的发生率无统计学差异。 结论 手术治疗对改善脊髓型颈椎病或/和神经根型颈椎病患者合并的眩晕症状是有效的,两种手术方式对颈性眩晕的缓解率无统计学差异。 相似文献
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目的:探讨肌内效贴布贴扎联合核心稳定训练对颈型颈椎病(neck type cervical spondylopathy,NTCS)患者的康复作用.方法:选取2020年1月至2020年12月海南医学院第一附属医院康复医学科收治的110例NTCS患者,随机分为对照组(55例)与研究组(55例).110例NTCS患者均接受常... 相似文献
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腰椎曲度变直时椎间盘病变的特点 总被引:1,自引:0,他引:1
目的 通过分析腰椎曲度变直患者腰椎间盘病变的发生情况,揭示T11~S1各椎间盘的不同类型病变对腰椎曲度的影响。方法 回顾分析腰椎曲度变直组(69例)和对照组(同一年龄组,腰椎曲度正常,共41例)T11-S1各椎间盘病变情况,分别观察椎间盘蜕变、突出、椎间隙狭窄的发生情况,在两组间对部分节段不同病变的发生率进行比较。结果 两组中T11-L2段椎间盘病变的发生率很低,在两组间无法进行统计学处理。L2-S1段椎间盘病变的发生率增高,腰椎曲度变直组除L2-3椎间盘突出和椎间隙狭窄与腰椎曲度正常组比较差异无显著性意义外(P>0.05),其余节段椎间盘蜕变,突出和椎间隙变窄在两组间差异均有显著性意义(P<0.05或P<0.001)。结论 腰椎曲度变直组病人下腰段(L2-S1)椎间盘病变发生率明显增高,说明腰椎间盘病变作为局部因素可能是腰椎曲度变直的诱因。 相似文献
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The scaling of postcranial muscles in cats (Felidae) I: forelimb,cervical, and thoracic muscles
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Emily L. Sparkes Marcela Randau Stephanie E. Pierce Andrew C. Kitchener John R. Hutchinson 《Journal of anatomy》2016,229(1):128-141
The body masses of cats (Mammalia, Carnivora, Felidae) span a ~300‐fold range from the smallest to largest species. Despite this range, felid musculoskeletal anatomy remains remarkably conservative, including the maintenance of a crouched limb posture at unusually large sizes. The forelimbs in felids are important for body support and other aspects of locomotion, as well as climbing and prey capture, with the assistance of the vertebral (and hindlimb) muscles. Here, we examine the scaling of the anterior postcranial musculature across felids to assess scaling patterns between different species spanning the range of felid body sizes. The muscle architecture (lengths and masses of the muscle‐tendon unit components) for the forelimb, cervical and thoracic muscles was quantified to analyse how the muscles scale with body mass. Our results demonstrate that physiological cross‐sectional areas of the forelimb muscles scale positively with increasing body mass (i.e. becoming relatively larger). Many significantly allometric variables pertain to shoulder support, whereas the rest of the limb muscles become relatively weaker in larger felid species. However, when phylogenetic relationships were corrected for, most of these significant relationships disappeared, leaving no significantly allometric muscle metrics. The majority of cervical and thoracic muscle metrics are not significantly allometric, despite there being many allometric skeletal elements in these regions. When forelimb muscle data were considered in isolation or in combination with those of the vertebral muscles in principal components analyses and MANOVAs, there was no significant discrimination among species by either size or locomotory mode. Our results support the inference that larger felid species have relatively weaker anterior postcranial musculature compared with smaller species, due to an absence of significant positive allometry of forelimb or vertebral muscle architecture. This difference in strength is consistent with behavioural changes in larger felids, such as a reduction of maximal speed and other aspects of locomotor abilities. 相似文献
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Siéssere S Vitti M de Sousa LG Semprini M Watanabe PC Hallak JE Regalo SC 《Electromyography and clinical neurophysiology》2006,46(4):223-228
AIM: This study had the goal of analyzing masseter and temporalis muscles of individuals with Eagle's Syndrome, establishing comparisons with healthy control individuals by means of electromyography, due to the importance of the masticatory musculature upon the various functions of the stomatognathic system and the effects of Eagle's syndrome on this system's functioning. METHOD: Ten women with Eagle's syndrome and ten healthy controls volunteered to participate in the study. A Myosystem I system, Prosecon Ltda (Uberlandia/MG, Brazil) with 12 channels was used Active differential electrodes were placed on the belly of both masseters and on the anterior temporalis. Firstly, rest position was registered and then the patients were instructed to clench their teeth with maximum strength for four seconds to register the Clenching at Usual Maximum Intercuspation. Next, the clinical conditions of chewing, mandible laterality, and water swallowing were performed. RESULTS: The normalized data of muscle activity during the different clinical conditions and at rest position were compared by Student's t test, considering two groups: controls and syndrome bearers. The masticatory muscles of every syndrome bearers showed hyperactivity during the analyzed clinical conditions; except for chewing, in which the right masseter did not show greater electromyographic activity. CONCLUSION: It is concluded that individuals with the syndrome showed muscular hyperactivity when compared to healthy individuals, due to the interference of the elongated styloid process, which leads to dysfunctions of the stomatognathic system in the syndrome bearers, with signs and symptoms related to craniofacial pain, dysphagia, otalgy, temporomandibular dysfunctions, and headache. 相似文献
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退变性颈椎失稳颈后深部肌肉的组织化学特征及其临床意义 总被引:10,自引:0,他引:10
目的:研究颈后深部肌肉的肌纤维型分布和横切面积,探讨其生理功能和在退变性颈椎失稳发病中的作用。方法:应用肌球蛋白ATP酶染色法,观察正常人(4例)和退变性颈椎失稳患者(4例)颈后深部肌肉各型肌纤维的比例和结构特征,并测量肌纤维的横切面积。结果:正常人和退变性颈椎失稳患者颈后深部肌肉Ⅰ型和Ⅱ型纤维交织排列,横切面呈多边形或椭圆形,Ⅰ型纤维数量及横切面积均显著大于Ⅱ型纤维。退变性颈椎失稳患者肌纤维边界不清,横切面上可见小空泡,Ⅰ型纤维减少,Ⅱ型纤维增多。结论:颈后深部肌肉对维持颈段脊柱的生理姿势和运动起重要作用,肌纤维病理学改变是退变性颈椎失稳发病的重要因素之一。 相似文献
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Feigenbaum SL Crites Y Hararah MK Yamamoto MP Yang J Lo JC 《Human reproduction (Oxford, England)》2012,27(9):2837-2842
BACKGROUND Pregnant women with polycystic ovarian syndrome (PCOS) experience a greater rate of adverse obstetrical outcomes compared with non-PCOS women. We examined the prevalence and incidence of cervical insufficiency (CI) in a community cohort of pregnant women with and without PCOS. METHODS A retrospective cohort study was conducted within a large integrated health care delivery system among non-diabetic PCOS women with second or third trimester delivery during 2002-2005 (singleton or twin gestation). PCOS was defined by Rotterdam criteria. A non-PCOS comparison group matched for delivery year and hospital facility was used to estimate the background rate of CI. Women were designated as having new CI diagnosed in the index pregnancy (based on cervical dilation and/or cervical shortening) and prior CI based on prior diagnosis of CI with prophylactic cerclage placed in the subsequent pregnancy. RESULTS We identified 999 PCOS women, of whom 29 (2.9%) had CI. There were 18 patients with new CI and 11 with prior CI having prophylactic cerclage placement; four CI patients had twin gestation. In contrast, only five (0.5%) non-PCOS women had CI: two with new CI and three with prior CI. The proportion of newly diagnosed incident CI (1.8 versus 0.2%) or prevalent CI (2.9 versus 0.5%) was significantly greater for PCOS compared with non-PCOS pregnant women (both P < 0.01). Among PCOS women, CI prevalence was particularly high among South Asians (7.8%) and Blacks (17.5%) compared with Whites (1%) and significantly associated with gonadotropin use (including in vitro fertilization). Overall, the PCOS status was associated with an increased odds of prevalent CI pregnancy (adjusted odds ratio 4.8, 95% confidence interval 1.5-15.4), even after adjusting for maternal age, nulliparity, race/ethnicity, body mass index and fertility treatment. CONCLUSION In this large and ethnically diverse PCOS cohort, we found that CI occurred with a higher than expected frequency in PCOS women, particularly among South Asian and Black women. PCOS women with CI were also more likely to have received gonadotropin therapy. Future studies should examine whether natural and hormone-altered PCOS is a risk factor for CI, the role of race/ethnicity, fertility drugs and consideration for heightened mid-trimester surveillance in higher risk subgroups of pregnant women with PCOS. 相似文献
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目的探讨甲基强的松龙(MP)在脊髓型颈椎病围手术期的疗效。方法将因脊髓型颈椎病行单纯前路减压的117例患者随机分为3组:A组40例,减压手术前在持续心电监护下于30 m in内以30 mg/kg剂量快速静脉滴注MP,术后1-3 d按照3 mg·kg^-1·d^-1剂量静滴MP;B组39例,仅术后1-3 d按照3 mg·kg^-1·d^-1剂量静滴MP;C组38例,仅术后1-3 d以10 mg地塞米松静脉滴注。术后常规给予脱水、预防溃疡及神经营养药物治疗。于术后3 d、7 d、180 d对3组患者的脊髓神经功能恢复情况及并发症发生率进行统计学分析。结果3组术前JOA评分无显著差异,术后A组神经功能恢复率优于B组和C组,B组术后1周内优于C组。术后各时相点JOA评分较术前显著提高(P〈0.01),各组之间术后并发症发生率无显著差异。结论脊髓型颈椎病围手术期给予MP治疗对于神经功能的恢复有良好疗效,且术前给予大剂量冲击治疗较单纯术后使用MP疗效更好。 相似文献
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Spondylocarpotarsal synostosis syndrome is a recently delineated autosomal recessive condition comprising short stature with short trunk, failure of normal spine segmentation resulting in block vertebrae and fusion of posterior elements, carpal and/or tarsal coalition, scoliosis, lordosis, pes planus, dental enamel hypoplasia, decreased range of motion or dislocation of the elbow, renal anomalies, and hearing loss. The vertebral segmentation defects may involve noncontiguous areas of the cervical, thoracic, and lumbar spine. Odontoid hypoplasia was noted in two cases. We report on a sporadic case of spondylocarpotarsal synostosis in a 5-year-old girl with hypoplasia of C1 and odontoid and subluxation of C2 upon C3. This brings the number of well-documented cases of spondylocar- potarsal synostosis to 19, and is the first documenting cervical spine instability. Careful evaluation for this complication should be considered in other cases. 相似文献
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Svanborg E 《Respiratory physiology & neurobiology》2005,147(2-3):263-272
This article reviews studies of upper airway muscles in humans, with emphasis on muscle fiber structural and electrophysiological changes observed in patients with obstructive sleep apnea syndrome (OSAS). The concept of OSAS as a progressive disease is discussed and also possible causes. These include local nervous lesions in the upper airway, both motor and sensory. Previous muscle biopsy studies have given evidence for motor neuron lesions such as, e.g., the phenomenon of type grouping in histological sections. New data obtained with concentric needle EMG recordings from the palatopharyngeus muscles are also presented. In 10/12 OSAS patients there were typical findings indicating motor neuropathy (reduced EMG activity at maximal voluntary effort, long and polyphasic motor-unit potentials and, in two cases, spontaneous denervation activity), whereas such findings were only present in 3/15 patients with habitual snoring. This supports the hypothesis that progression from habitual snoring to the clinical disease of OSAS could be attributed to peripheral neurogenic lesions. 相似文献