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51.
Shengxuan Cao Chen Wang Xin Ma Xu Wang Jiazhang Huang Chao Zhang Li Chen Xiang Geng Kan Wang 《Journal of orthopaedic research》2019,37(8):1860-1867
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019 相似文献
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目的:观察抑郁症大鼠模型脑组织不同部位神经营养因子水平的变化及抗抑郁药物使用后改变。方法:将成年SD大鼠30只分为正常对照组、模型对照组、药物干预组,每组10只,雌雄对半;正常组正常养殖,模型组采用慢性不可预知应激结合孤养方式制备抑郁模型大鼠4周。药物干预组采用模型组造模过程4周后给予药物(氟西汀)给入,自实验开始之后每周观察大鼠体重、糖水消耗、旷场实验指标的变化,最后采用荧光定量PCR法观察大鼠脑部BDNF因子及Trkb的表达。结果:与正常对照组大鼠相比,模型组大鼠体重增加缓慢、糖水消耗减少、旷场试验各项指标较正常组间差异具有统计学意义;荧光定量PCR结果显示:模型组较对照组各脑区BDNF及Trkb受体表达减少,药物干预组脑区BDNF及Trkb受体表达显著高于模型对照组。结论:脑部BDNF因子及Trkb的表达在抑郁症发生与治疗中有所改变。 相似文献
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Sweeka Alexander Gurjeet Dulku Sharbell Hashoul Donna B Taylor 《Journal of Medical Imaging and Radiation Oncology》2019,63(4):473-478
Contrast‐enhanced spectral mammography (CESM) has a number of uses including the work‐up of inconclusive findings on mammography, assessment of breast symptoms, cancer staging, evaluation of response to neoadjuvant chemotherapy and recently as an alternative to magnetic resonance imaging (MRI) in high‐risk screening. CESM can be swiftly incorporated into the workflow of busy breast clinics. We share our experiences with CESM at a large breast assessment centre in Western Australia. 相似文献
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《Sleep medicine》2020
ObjectivesHyperechogenicity of the substantia nigra (SN) and abnormal dopamine transporter-single-photon emission computed tomography (DAT-SPECT) are biomarkers commonly used in the assessment of prodromal synucleinopathy. Our goals were as follows: (1) to compare echogenicity of SN in idiopathic rapid eye movement (REM) behavior disorder (iRBD), Parkinson's disease (PD) without RBD (PD-noRBD), PD with RBD (PD + RBD), and control subjects; and (2) to examine association between SN degeneration assessed by DAT-SPECT and SN echogenicity.Patients/methodsA total of 61 subjects with confirmed iRBD were examined using Movement Disorders Society-unified PD rating scale (MDS-UPDRS), TCS (transcranial sonography) and DAT-SPECT. The results were compared with 44 patients with PD (25% PD + RBD) and with 120 age-matched healthy subjects.Results and conclusionThe abnormal SN area was found in 75.5% PD, 23% iRBD and 7.3% controls. Median SN echogenicity area in PD (0.27 ± 0.22 cm2) was higher compared to iRBD (0.07 ± 0.07 cm2; p < 0.0001) and controls (0.05 ± 0.03 cm2; p < 0.0001). SN echogenicity in PD + RBD was not significantly different from PD-noRBD (0.30 vs. 0.22, p = 0.15).Abnormal DAT-SPECT was found in 16 iRBD (25.4%) and 44 PD subjects (100%). No correlation between the larger SN area and corresponding putaminal binding index was found in iRBD (r = −0.13, p = 0.29), nor in PD (r = −0.19, p = 0.22).The results of our study showed that: (1) SN echogenicity area in iRBD was higher compared to controls, but the hyperechogenicity was present only in a minority of iRBD patients; (2) SN echogenicity and DAT-SPECT binding index did not correlate in either group; and (3) SN echogenicity does not differ between PD with/without RBD. 相似文献
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