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51.
BackgroundThe effect of tibiofemoral geometry on musculoskeletal function is important to movement biomechanics.Research questionWe hypothesised that tibiofemoral geometry determines tibiofemoral motion and musculoskeletal function. We then aimed at 1) modelling tibiofemoral motion during normal activity as a function of tibiofemoral geometry in healthy adults; and 2) quantifying the effect of tibiofemoral geometry on musculoskeletal function.MethodsWe used motion data for six activity types and CT images of the knee from 12 healthy adults. Geometrical variation of the tibia and femoral articular surfaces were measured in the CT images. The geometry-based tibiofemoral motion was calculated by fitting a parallel mechanism to geometrical variation in the cohort. Matched musculoskeletal models embedding the geometry-based tibiofemoral joint motion and a common generic tibiofemoral motion of reference were generated and used to calculate joint angles, net joint moments, muscle and joint forces for the six activities analysed. The tibiofemoral model was validated against bi-planar fluoroscopy measurements for walking for all the six planes of motion. The effect of tibiofemoral geometry on musculoskeletal function was the difference between the geometry-based model and the model of reference.ResultsThe geometry-based tibiofemoral motion described the pattern and the variation during walking for all six motion components, except the pattern of anterior tibial translation. Tibiofemoral geometry had moderate effect on cohort-averages of musculoskeletal function (R2 = 0.60–1), although its effect was high in specific instances of the model, outputs and activities analysed, reaching 2.94 BW for the ankle reaction force during stair descent. In conclusion, tibiofemoral geometry is a major determinant of tibiofemoral motion during walking.SignificanceGeometrical variations of the tibiofemoral joint are important for studying musculoskeletal function during normal activity in specific individuals but not for studying cohort averages of musculoskeletal function. This finding expands current knowledge of movement biomechanics.  相似文献   
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[目的]评估规律性八段锦运动对视神经脊髓炎谱系疾病患者残疾状态及日常生活能力恢复情况的影响。[方法]选取视神经脊髓炎谱系疾病患者58例,随机分成试验组和对照组,每组29例,分别给予常规药物治疗+基础训练+八段锦干预、常规药物治疗+基础训练,疗程12周。比较两组扩展残疾状态量表(EDSS)评分、Barthel指数、Ashworth评分和疲劳严重度量表(FSS)评分的变化情况。[结果]试验组中,患者的EDSS评分、Barthel指数、Ashworth评分和FSS评分较干预前明显改善,差异具有统计学意义(P0.05);与对照组比较,EDSS评分和Barthel指数改善具有统计学意义(P0.05)。对照组中,患者Barthel指数、Ashworth评分和FSS评分较干预前明显改善(P0.05)。两组这4项指标的改善程度比较中,与对照组比较,试验组在EDSS评分、Barthel指数、Ashworth评分和FSS评分的改善程度更明显(P0.05)。[结论]规律的八段锦干预能明显改善视神经脊髓炎谱系疾病患者残疾状态、日常生活能力、肢体痉挛程度和疲劳状态,适合临床推广应用。  相似文献   
53.
郭欣  孙蓉 《中草药》2020,51(11):3070-3077
自新型冠状病毒肺炎(COVID-19)疫情暴发以来,国家卫生健康委员会及各地相关单位陆续发布多个诊疗方案,其中重症期治疗推荐方剂中黄连解毒汤的中医证侯与《新型冠状病毒肺炎诊疗方案(试运行第七版)》中重型气营两燔证相应,可用于治疗气营两燔证。气营两燔证津液营阴耗损、正不敌邪,气营热毒炽盛,黄连解毒汤清热解毒,可通过祛邪达到扶正护阴的治疗目的。现代药理研究表明黄连解毒汤在治疗COVID-19重型气营两燔证中具有潜在的抗炎解热、抗病毒、抗氧化、调节机体免疫力、保护脏器组织等作用。通过对COVID-19重型气营两燔证的病机演变、黄连解毒汤的方证关系及现代药理作用进行梳理,分析黄连解毒汤治疗重型气营两燔证的中医方证关系及现代药理学基础,以期为黄连解毒汤用于COVID-19重型气营两燔证的有效治疗提供依据。  相似文献   
54.
《Saudi Pharmaceutical Journal》2020,28(10):1172-1181
Combination of antibiotics with natural products is a promising strategy for potentiating antibiotic activity and overcoming antibiotic resistance. The purpose of the present study was to investigate whether morusin and kuwanon G, prenylated phenolics in Morus species, have the ability to enhance antibiotic activity and reverse antibiotic resistance in Staphylococcus aureus and Staphylococcus epidermidis. Commonly used antibiotics (oxacillin, erythromycin, gentamicin, ciprofloxacin, tetracycline, clindamycin) were selected for the combination studies. Checkerboard and time-kill assays were used to investigate potential bacteriostatic and bactericidal synergistic interactions, respectively between morusin or kuwanon G and antibiotics. According to both fractional inhibitory concentration index and response surface models, twenty combinations (14 morusin-antibiotic combinations, six kuwanon G-antibiotic combinations) displaying bacteriostatic synergy were identified, with 4–512-fold reduction in the minimum inhibitory concentration values of antibiotics in combination. Both morusin and kuwanon G reversed oxacillin resistance of methicillin-resistant Staphylococcus aureus. In addition, morusin reversed tetracycline resistance of Staphylococcus epidermidis. At half of the minimum inhibitory concentrations, combinations of morusin with oxacillin or gentamicin showed bactericidal synergy against methicillin-resistant Staphylococcus aureus. Fluorescence and differential interference contrast microscopy and scanning electron microscopy showed an increase in the membrane permeability and massive leakage of cellular content in methicillin-resistant Staphylococcus aureus exposed to morusin or kuwanon G. Overall, our findings strongly indicate that both prenylated compounds are good candidates for the development of novel antibacterial combination therapies.  相似文献   
55.
目的探讨血清TRAb IgG各亚型在不同活动分期甲状腺相关性眼病(thyroid-associated ophthalmopathy,TAO)患者中的分布特点,及其在评估TAO活动度中的价值。方法选取2018年8月至2019年2月郑州大学第一附属医院收治的TAO患者43例,依据临床活动度评分(clinical activity score,CAS)进一步分为活动期组(AP组,CAS≥3分,22例)和静止期组(IP组,CAS<3分,21例);Graves病患者(GD组)30例,桥本甲状腺炎患者(HT组)19例,并以同期健康体检者(NC组)50名作为正常对照。收集各组受试者临床基本资料,化学发光免疫法检测血清FT3、FT4、TSH、甲状腺过氧化物酶抗体(TPOAb)、甲状腺球蛋白抗体(TgAb)、促甲状腺激素受体抗体(TRAb)水平,酶联免疫吸附法检测血清TRAb IgG和IgG各亚型的百分结合率[binding rate in percentage,(B)],比较各亚型的阳性率和阳性亚型的相对含量。结果(1)与HT组相比,TAO组、GD组IgG1、IgG2阳性率降低,差异有统计学意义(P<0.05)。各疾病组间TRAb IgG亚型相对含量无明显差异(P>0.05)。(2)与IP组相比,AP组IgG1(B)、IgG1阳性率显著升高,IgG4(B)、IgG4相对含量显著降低(P<0.05)。(3)IgG1(B)与TAO活动度呈正相关(B=6.190,P=0.007),IgG4(B)越高越倾向于静止期,但差异无统计学意义(B=-16.390,P=0.052)。(4)活动率评估TAO处于活动期的受试者工作特征(ROC)曲线下面积为0.859(95%CI 0.746~0.973,P<0.05),当活动率为4.29时,约登指数最大,其判断敏感度为81.8%,特异度为81.0%。结论在TAO患者中血清TRAb IgG1水平升高提示疾病趋向活动期,IgG4水平升高提示疾病趋向静止期。活动率可为评估TAO是否处于活动期提供参考依据。  相似文献   
56.
57.
Abstract

This study tested whether the effect of self-referencing in a health-marketing message was amplified or attenuated when combined with message framing and narrative. Hispanic adults (N?=?146) were randomly assigned to read and respond to an obesity prevention message. Self-referencing messages generated greater cognitive elaboration but only when placed in a narrative. Conversely, self-referencing messages highlighting health risks of obesity produced higher levels of involvement and intention to increase physical activity and healthy eating. Health marketing professionals can use these findings to enhance the effectiveness of obesity prevention messages that target Hispanic adults.  相似文献   
58.
59.
Background/objectivesThis study aimed to examine the variations of circadian activity rhythm of children according to objective body mass index (BMI) values, using a novel statistical framework (ie, Functional Linear Modeling, FLM), separately for school- and weekend days.MethodsA total of 107 participants (60 females; mean age: 10.25 ± 0.48 years) wore an actigraph for seven days during a regular school-week. While valid actigraphic data during school days were available for each of these children, this number decreased to 53 (31 females; mean age: 10.28 ± 0.51 years) during weekend days.ResultsExamining the school days, significantly higher motor activity in participants with higher BMI was observed from around 4:00 a.m. to 6:00 a.m., with a peak about 5:00 a.m. On the contrary, applying the FLM to the weekend days actigraphic data, no significantly different variation of circadian activity rhythm was observed, according to BMI.ConclusionsIn this specific sample of children, during school days, higher BMI is associated with higher activity level in a specific time window in the second half of nocturnal sleep. The lack of significant findings during weekend days could be explained because of higher variability of get-up time and/or the reduced sample size. Future longitudinal studies could explore if the higher motor activity in that specific time window qualifies as a predictive marker of the development of overweight and obesity. If so, early preventive strategies directed towards those at higher risk could be effectively implemented.  相似文献   
60.
目的:采取不同的提取方法研究菲牛蛭炮制前后抗凝活性变化。方法:分别采用水提取法及模拟胃肠道环境的仿生提取法提取菲牛蛭活体冻干品、清水吊干品、滑石粉烫制品、酒浸闷烘品中的活性成分,测定活化部分凝血酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)、抗凝血酶活性4个凝血指标,并采用Lorry法测定其蛋白含量,综合评价2种提取方法下的菲牛蛭及其炮制品的抗凝活性。结果:无论是水提取法,还是仿生提取法,APTT、PT、TT均显示炮制后抗凝活性降低,抗凝活性顺序为活体冻干品>清水吊干品>酒浸闷烘品>滑石粉烫制品,此结果与抗凝血酶活性及蛋白含量顺序一致。结论:高温炮制方法会降低菲牛蛭的抗凝活性。  相似文献   
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