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PurposeTo create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE).Materials and MethodsFluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4–6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4–6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75–250-μm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest.ResultsThe mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed.ConclusionsA nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.  相似文献   
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BackgroundVisually induced dizziness can develop as a sequala of a vestibular disorder and is characterized by symptoms of nausea, dizziness, and imbalance in rich visual environments such as supermarkets and shopping malls. To date the mechanisms underlying visually induced dizziness are poorly understood.Research questionWhat are the characteristics of visual fixations and postural sway in adults with visually induced dizziness compared to healthy adults when exposed to increasingly complex visual environments?MethodsWe recruited 20 adults with visually induced dizziness and 20 healthy adults to this cross-sectional exploratory study. Participants were instructed to maintain gaze on letters projected on a large screen with backgrounds of differing visual complexity. The number of visual refixations, movement of the centre of pressure, and movement of the head and body centres of mass were recorded.ResultsAdults with visually induced dizziness showed a significantly higher number of visual refixations (F= 10.592, p < 0.01), and increased mean velocity of head and body centres of mass movement (F= 14.034, p < 0.01 and F= 6.553, p < 0.05 respectively) compared to healthy adults.SignificanceAdults with visually induced dizziness exhibited visual fixational instability and increased postural and head sway compared to healthy adults. This was mainly observed in conditions with complex and moving backgrounds. This may account for reports from adults with visually induced dizziness of worsening symptoms in busy environments. The results from the study may assist in guiding intervention development to reduce symptoms of visually induced dizziness.  相似文献   
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目的研究阴道顺产与剖宫产对初产妇产后早期盆底功能的影响。方法选择2020年1月至12月在阳春市人民医院产科中心分娩的120例初产妇展开研究,按照分娩方式的不同分为对照组与观察组,每组各60例。对照组为阴道顺产,观察组采用剖宫产,两组均在产后第6周进行早期盆底功能检查,并进行盆底康复治疗,比较两组的治疗效果。结果观察组的尿失禁、阴道脱垂、子宫脱垂发生率低于对照组,差异有统计学意义(P<0.05);观察组治疗后的盆底肌力分级情况优于对照组,差异有统计学意义(P<0.05);观察组治疗后的膀胱颈与耻骨联合下缘水平线间的垂直距离(BSD)高于对照组,膀胱尿道后角(RA)、膀胱颈移动度(BND)低于对照组,差异均有统计学意义(P<0.05)。结论阴道顺产对于盆底功能及盆腔结构的不良影响大于剖宫产,盆底功能障碍性疾病发生率更高,而康复治疗可有效改善阴道顺产、剖宫产初产妇的盆底功能,剖宫产初产妇的盆底功能恢复更好。  相似文献   
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随着人口老龄化和生育力的下降,我国放开了三孩政策,对有生育要求的夫妇进行生育力评估显得非常必要。女性生育力与年龄关系密切,还依赖于卵巢、输卵管、子宫等生殖器官。本文就影响女性生育力的因素进行介绍。  相似文献   
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儿童哮喘与慢性阻塞性肺疾病(COPD)是儿童期与成人期常见的存在气流受限的慢性气道疾病。研究发现,儿童哮喘会增加成年期罹患COPD的风险,而肺功能变化是预测COPD患病风险的重要指标。针对哮喘患儿建立长期肺功能监测管理,对于评估其成年后存在不可逆气道阻塞的风险有重要意义。文章综述儿童哮喘与COPD相关的研究进展。  相似文献   
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