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61.
Background: Previous studies have distilled the Upright Motor Control Test Knee Extension and Knee Flexion subscales (UMCT-KE and UMCT-KF, respectively) from the original 6-item instrument and examined these as stand-alone rapid tests of voluntary movement control in the standing position. Systematic review evidence suggests that the UMCT-KE and UMCT-KF may have value in predicting walking ability after stroke.

Objective: To examine the interrater and intrarater reliability, and concurrent validity of the UMCT-KE and UMCT-KF, and associations with walking ability in adults with subacute stroke.

Methods: A prospective repeated assessments design was implemented in a rehabilitation department in a public teaching hospital. A consecutive sample of patients with subacute first-time stroke (N = 50; mean age = 51 ± 12 years; 20 females; mean time post-stroke = 68 ± 48 days) completed the study. Three physical therapists independently administered the UMCT-KE and UMCT-KF on two testing occasions 2 days apart (t1 and t2). On t2, a fourth rater administered the Leg subscale of the Motricity Index (MI-Leg) as criterion standard.

Results: The UMCT-KE and UMCT-KF demonstrated substantial to almost perfect interrater and intrarater reliability (= 0.77–0.95), with lower limits of 95% confidence intervals extending to no lower than the substantial level. Both the UMCT-KE and UMCT-KF showed high correlations with the MI-Leg (ρ = 0.747–0.775) and significant associations with walking ability. p Values for all tests were <0.001.

Conclusions: The UMCT-KE and UMCT-KF are reliable and valid tests for rapidly estimating voluntary movement control of the lower limbs in adults with subacute stroke.  相似文献   

62.
Context: We sought to describe our experience with the Hybrid Assistive Limb® (HAL®) for active knee extension and voluntary ambulation with remaining muscle activity in a patient with complete paraplegia after spinal cord injury.

Findings: A 30-year-old man with complete paraplegia used the HAL® for 1 month (10 sessions) using his remaining muscle activity, including hip flexor and upper limb activity. Electromyography was used to evaluate muscle activity of the gluteus maximus, tensor fascia lata, quadriceps femoris, and hamstring muscles in synchronization with the Vicon motion capture system. A HAL® session included a knee extension session with the hip flexor and voluntary gait with upper limb activity. After using the HAL® for one month, the patient’s manual muscle hip flexor scores improved from 1/5 to 2/5 for the right and from 2/5 to 3/5 for the left knee, and from 0/5 to 1/5 for the extension of both knees.

Conclusion/clinical relevance: Knee extension sessions with HAL®, and hip flexor and upper-limb-triggered HAL® ambulation seem a safe and feasible option in a patient with complete paraplegia due to spinal cord injury.  相似文献   

63.
A free clinic in rural New England recently implemented an exercise prescribing program. As a follow-up, a pilot survey questionnaire was sent by mail to a sample of 206 patients to assess their preferences for support of physical activity efforts. A total of 57 surveys were returned for a response rate of 28%. Patients preferred low-impact, low-cost, and low-intensity physical activity. Survey respondents identified no clear preference for group activity versus individual activity. Key findings included patient preferences for the use of low-fidelity education materials, a fitness advisor, and peer support to encourage physical activity.  相似文献   
64.
目的对虎杖中1个新的R2R3-MYB转录因子基因PcMYB1进行转录活性鉴定和表达特性分析,并在转基因拟南芥中进行功能研究。方法利用酵母单杂交实验分析PcMYB1的转录活性;荧光定量PCR(RT-PCR)技术检测虎杖中PcMYB1的表达模式;利用Wiesner染色和溴乙酰法检测PcMYB1转基因拟南芥中的木质素含量;RT-PCR技术分析PcMYB1转基因拟南芥木质素合成相关基因的表达。结果酵母单杂实验结果表明,PcMYB1具有转录抑制活性;RT-PCR结果显示PcMYB1在虎杖根、茎、叶中均有表达,在叶中表达量最高,并且紫外照射处理可诱导叶片中PcMYB1的表达;与野生型拟南芥相比,转基因拟南芥的株高降低了24.07%,木质部的细胞染色程度浅,转基因拟南芥木质素含量降低了14.81%,参与木质素合成的AtC4H、AtC3H、AtF5H、AtCOMT、AtCAD基因表达下调。结论 PcMYB1具有转录抑制活性,对植物木质素合成具有负调控作用。  相似文献   
65.
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
66.
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   
67.
68.
目的 制备高纯度3,5-O-二咖啡酰基奎宁酸,并评价其对人宫颈癌HeLa细胞的抗增殖活性。方法 采用柱色谱提取法和中压液相色谱法从奇蒿花中分离、纯化得到高纯度的3,5-O-二咖啡酰基奎宁酸。采用MTT法评价该化合物对人宫颈癌HeLa细胞的体外抗增殖活性。结果 柱色谱提取的提取率和中压液相色谱法的回收率分别为99.0%,61.2%,总回收率为54.0%。随着3,5-O-二咖啡酰基奎宁酸浓度升高,HeLa细胞存活率下降,细胞形态损伤增加,受试药物的IC50值为26.5µg·mL-1结论 本研究提供了一种简单、高效、节能的3,5-O-二咖啡酰基奎宁酸制备方法。3,5-O-二咖啡酰基奎宁酸对HeLa细胞具有一定的体外抗增殖活性。  相似文献   
69.
PurposeExercise may be an alternative strategy to helping early-stage breast cancer (ESBC) patients manage their cancer-related fatigue and anxiety during radiation therapy. This observational study aims to investigate the impact of self-reported exercise on fatigue and anxiety levels pre (T0), mid (T1), and post (T2) radiation therapy in patients with ESBC.MethodsFollowing informed consent, subjects completed three standardized questionnaires measuring physical activity, fatigue/quality of life, and anxiety at T0, T1, and T2.ResultsA total of 58 female patients (57 ± 9 years) completed this study. Mean activity level at T0 was 2548 (3292) metabolic equivalent units (METs), T1 was 3072 (3974) METs, and T2 was 2963 (2442) METs. There was no significant change between the three time points with measures of physical activity. Many patients moved from the moderately active group at T0 to the active group at T1. The mean T0 score using the quality of life questionnaire was 38.97 (11.30), T1 was 36.93 (11.69), and T2 was 35.36 (11.18). There was no significant change between the three time points with measures of quality of life (P = .211). There was statistical significance at P = .025 at T1 for lower quality of life compared to T0 across all exercise types. There was also statistical significance at P = .026 at T1 for the active group with higher quality of life compared to the inactive one. All three physical activity categories showed a decline in quality of life scores over time. Anxiety decreased between the three time point measurements. Mean T0 score for anxiety was 47.33 (5.95), T1 was 43.16 (6.49), and T2 was 38.48 (8.46). The interaction of exercise level and time is not significant for anxiety (P = .91). There was statistical significance (P = .015) for anxiety at T2 compared to T1 across exercise types.DiscussionThis study demonstrated that ESBC patients showed signs of fatigue and anxiety while undergoing radiation therapy regardless of self-reported exercise measured by a physical activity questionnaire. Several trends were observed that showed improved outcomes for patients consistent with previously published studies. The present study highlights a nonsignificant change in fatigue. As fatigue is one of the main side effects from radiation, it may be difficult to demonstrate significance. There are some studies in the field that demonstrate significance between fatigue and exercise with larger sample sizes. The results also highlight a decrease in anxiety from the baseline to the end of treatment. It is postulated that patients become less anxious as treatment progresses due to familiarity of a routine. The present study is limited by several factors including sample size and the study not being a randomized controlled one.ConclusionsExercise may reduce anxiety during radiation treatment for ESBC patients. Further investigation is required to assess the impact of fatigue.  相似文献   
70.
目的:研究外源NO对刺五加种子解除休眠及萌发过程中内源激素及酶的变化规律,为打破刺五加种子休眠和人工栽培提供依据。方法:考察不同浓度(1,5,10,20 mmol·L~(-1))的外源NO供体硝普钠(SNP)处理刺五加种子,而后进行变温层积处理。采用高效液相色谱法检测出在不同层积时间(0,30,50,80,100,130 d)的内源激素赤霉素(GA3),脱落酸(ABA),吲哚乙酸(IAA),吲哚丁酸(IBA)及水杨酸(SA)含量变化。采用酶标仪全程监测体内酶[过氧化氢酶(CAT),超氧化物歧化酶(SOD),过氧化物酶(POD),丙二醛(MDA)]水平的变化。结果:在刺五加种子萌发过程中,GA3,IAA,IBA和SA的含量逐渐增大,脱落酸的含量逐渐减小。POD和MDA水平显著下降,CAT和SOD的酶活力显著上升。外源NO可以提高刺五加种子萌发率,缩短种子萌发时间,20 mmol·L~(-1)SNP促进种子萌发效果最为明显,10 mmol·L~(-1)SNP促进种子萌发效果最弱,呈"V"型变化。结论:SNP促进刺五加种子萌发可能通过提高种子萌发过程中的激素和酶的含量,以提高种子内源NO含量而实现。  相似文献   
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