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1.
目的:优化白及多糖的超声提取工艺,比较不同产地白及多糖含量差异,考察白及多糖稳定性和抗氧化活性。方法:以多糖得率为考察指标,料液比、超声温度、超声时间为考察因素设计L9(34)正交试验优化白及多糖超声波提取工艺;以苯酚-硫酸法测定白及多糖含量,考察陕西汉中、云南普洱、湖南洪江及四川绵阳白及多糖含量产地差异;以化学方法考察白及多糖稳定性,并比较白及多糖对1,1-二苯基-2-苦肼基自由基(DPPH·)和羟基自由基(·OH)的清除率以评价其体外抗氧化活性。结果:最佳超声提取工艺条件为:料液比1:25(g/mL)、超声温度80 ℃、超声时间10 min;四川绵阳白及多糖含量最高,达到60.81%,湖南洪江次之,云南普洱最低;白及多糖在柠檬酸及中性溶液中的稳定性较好,在苯甲酸钠、过酸性或过碱性溶液中的稳定性较差;白及多糖能有效地清除DPPH和羟基自由基,具有潜在的体外抗氧化活性。结论:白及多糖超声波提取工艺的优化及其抗氧化活性研究,可为白及多糖提取及综合利用提供借鉴。  相似文献   
2.

Objective

The aim of the study was to assessment the impact of hip osteoarthritis on postural stability.

Methods

One hundred and twenty-five randomly selected women 20–85 years old (mean age of 49 ± 24.4 years) were assigned to three groups based on age, health status and activity level. Group 1 (cases) – elderly women with diagnosed hip osteoarthritis, group 2 (control) - women without hip osteoarthritis, and group 3 (control) - healthy young women. Assessment of postural stability were measured using a WIN-POD Pel 38 electronic podometer. Statistica 10 software was used to perform t-test resulting in significance level of p < 0.05.

Results

Significant differences in pedobarographic balance measurements were observed between the study groups with eyes opened or closed (deviation length eyes open: group 1–3 and 2–3 p < 0.0001; eyes closed group 1–2 p = 0.19; 1–3 and 2–3 p < 0.0001; deviation area eyes open: group 1-3 and 2–3 p < 0.0001; eyes closed group 1–3 and 2–3 p < 0.0001; deviation velocity eyes open: group1-3 and 2–3 p < 0.0001; eyes closed group 1–2 p < 0.010, 1–3 and 2–3 p < 0.0001). The poorest postural stability was observed in patients with hip osteoarthritis (deviation length eyes open vs eyes closed 180.8/201.7 p = 0.028, deviation area 128.7/145.7 p = 0.771, deviation velocity 5.1/6.1 p < 0.0001), and the best postural stability was observed in young women (deviation length 111.3/137.5 p < 0.0001, deviation area 57/76.9 p = 0.003, deviation velocity 3.4/4.2 p < 0.0001).

Conclusion

(1) Osteoarthritic degeneration of the hip joint results in a significant disturbance in proprioception. This finding was reflected by the inferior stability parameters collected from subjects with hip osteoarthritis when asked to stand with their eyes closed. These finding were not observed in the other groups. (2) The disorder of the body stability of people with osteoarthritis may be a relative indication for the implantation of hip arthroplasty.  相似文献   
3.
BackgroundTai Chi (TC) training has been increasingly used to prevent falls. However, the underlying biomechanical mechanisms of TC training which influence fall risk remain unknown. As a result, the selection of TC forms differs among studies, leading to inconsistent results.Research questionIs dynamic stability different between the simplified 24 Yang-style TC forms among adults with knee osteoarthritis?MethodsTen participants with mild to moderate knee osteoarthritis were recruited. Under one-on-one instruction by an experienced TC master, each participant learned how to correctly perform the 24-form TC movements. Participants’ full-body kinematic and kinetic data was collected during walking trials and performance of the respective TC forms. Their dynamic stability was calculated in both sagittal and frontal planes and compared between each TC form and regular walking.ResultsThe results indicate that dynamic stability in both planes significantly varies among forms. Moreover, some forms pose a greater challenge to dynamic stability in comparison to others. The most challenging TC forms are Form 8 for stability in the sagittal plane and Form 10 in the frontal plane. Among all forms, Form 1 appears to be the least challenging.SignificanceOur findings could provide foundational information to identify the best TC forms for optimizing the effectiveness of TC-based fall prevention interventions.  相似文献   
4.
目的 建立小单孢菌FIM02523菌液中rakicidin B组分安全有效的提取方法。方法 在单因素试验以及稳定性研究的基础上,选取三因素三水平,采用Box-Behnken响应面法优化设计确定rakicidin B组分最佳提取条件。结果与结论 对rakicidin B提取率的主要影响因素依次为提取次数、料液比和提取溶剂的体积百分比浓度。优化修正后的提取条件为:常温下(4~40℃)、pH值6~7.5、提取溶剂为90%乙醇溶液、料液比1:3(V/V)、提取时间0.5h和提取次数2次,rakicidin B总提取率达到98.58%。  相似文献   
5.
6.
BackgroundWalking aids are designed for structural support during walking, however, surprisingly self-reported use of a walking aid (“Yes, I use one.”) has been identified as a risk factor for falling. Adjustment and design of walking aids may affect their usefulness in facilitating a stable walking pattern. We previously identified that increased body weight transfer onto a walking frame (‘device loading’) is associated with increased user stability.Research questionWe asked: “Could adjustment of walking frame height to a lower height than clinically recommended serve as a mechanism to facilitate device loading and thereby increase stability? And: “Do ultra-narrow frames have an adverse effect on stability as compared to standard-width frames?MethodsTen older adults that were users of front-wheeled walking frames walked with walking frames of 1) ‘standard width, standard height’, 2)‘standard width, low height’, 3)‘narrow width, standard height’. Smart Walker technology was used to record forces acting on the walking frame and inside the user’s shoes, and cameras recorded relative position of the user’s feet in relation to the frame’s feet. Stability of the user-frame system and device loading (percent body weight transferred onto the frame) were calculated. A general linear mixed effects model was used for statistical analysis.ResultsA lower height setting did not increase device loading and stability, therefore adjusting the height to a lower setting proved to be an unsuccessful mechanism to increase stability. However, device loading was positively correlated with stability for all frame conditions (p < 0.05). Finally, stability was reduced when walking with the ultra-narrow, as compared to standard-width, frame (p = 0.002).SignificanceTo increase stability in fall-prone users, active encouragement to transfer body weight onto the walking frame is needed. Considering the adverse effects of ultra-narrow frames on stability, such frames should be prescribed and used with caution.  相似文献   
7.
Serum eye drops (SED) have shown beneficial effects in patients suffering from dry eye syndrome and are manufactured for an increasing number of patients in Australia every year. Previous studies have examined the stability of serum growth factors during storage in either experimental vessels not used as the final packaging system or in eye drop bottles. To ensure the quality and safety of SED product manufactured in Australia, the stability of growth factors in serum packaged into two different systems during storage at different temperatures was examined. Healthy blood donors provided a whole blood donation, from which serum was prepared, diluted to 20% and dispensed into either a tube or a vial packaging system. The stability of growth factors, fibronectin and total protein in tube segments was comparable to matched vials samples during storage at −30 °C, 4 °C, 22 °C and 37 °C, with the exception of EGF and fibronectin in 20% SED stored in tube segments, which were more sensitive to storage conditions at 4 °C and 22 °C when compared to vials. Additionally, the growth factor, fibronectin and total protein concentration in both tube segments and vials was stable during storage at −30 °C for at least 9 months. This study highlights the impact of different manufacturing procedures on serum growth factor stability during storage.  相似文献   
8.
《Clinical microbiology and infection》2021,27(11):1698.e1-1698.e4
ObjectivesThere is an urgent need to ameliorate the possibilities of transporting reconstituted mRNA vaccines from the centralized preparation centres to the vaccination sites to improve the efficiency of the vaccination campaign against coronavirus disease 2019 (COVID-19). We have analysed the integrity of the Pfizer–BioNTech and Moderna vaccines under different movement conditions to provide information that may improve the distribution of vaccines to the target population.MethodsSyringes of reconstituted Pfizer–BioNTech or Moderna COVID-19 vaccines were prepared in a laminar flow chamber to be subjected to a stability analysis in order to evaluate the impact of movement on mRNA integrity. RNA integrity was checked by the lack of RNA peaks under the original mRNA peak in the electropherogram resulting from potential fragments from RNA degradation. Samples were then exposed for 180 min at room temperature (21 ± 1°C, 55 ± 10% humidity) under different movement conditions.ResultsWe report that the integrity of the mRNA in the reconstituted COVID-19 vaccines after continuous moderate movement at room temperature is maintained for at least 3 hours, with values of fluorescence units (FU) under the original mRNA peak of 0.38 ± 0.06 in the Pfizer–BioNTech vaccine and 0.96 ± 1.18 FU in the Moderna vaccine, equal to the values obtained without movement (0.36 ± 0.08 FU in the Pfizer–BioNTech and 1.12 ± 0.19 FU in the Moderna). In contrast, the integrity of these vaccines exposed to repeated Vortex shaking was significantly impaired (p < 0.001) with values under the original mRNA peak of 1.34 ± 0.31 FU for the Pfizer–BioNTech and 5.03 ± 1.16 FU for the Moderna samples.ConclusionsThe stability of these reconstituted vaccines reported here may improve the efficiency of the ground transportation and distribution of the vaccines, which may lead to shorter and more homogeneous vaccinations in cities and rural areas.  相似文献   
9.
BackgroundPlantar fasciitis (PF) is a common overuse injury experienced by runners. PF may decrease the ability of the plantar fascia to create tension and reduce stability of the foot. Stability of the foot is necessary for whole-body dynamic stability during running which consists of cyclical periods of single leg stance. Given that a major risk factor for running-related injury is previous injury, evaluating dynamic stability in runners with PF, runners with resolved PF, and healthy runners may elucidate differences between these individuals and clarify risk for secondary injury in these groups.Research questionIs dynamic stability reduced in runners with PF and runners with resolved PF compared to healthy runners?MethodsThirty runners were recruited for this retrospective comparative study based on mileage and injury status: current PF (PF), resolved PF (RPF), or healthy (CON). Kinematic and kinetic data were collected during running and dynamic stability was determined by time-to-contact (TtC) analysis for early, mid, and late stance to the anterior, posterior, medial, and lateral boundary of the foot. Dynamic stability was compared between groups one-way ANOVAs (α = 0.05) and Tukey post-hoc tests conducted when appropriate. Cohen’s d effect sizes (d) were reported for all TtC comparisons (small = 0.20, medium = 0.50, large = 0.80).ResultsTtC values were shorter in PF compared to the other groups to all boundaries during mid-stance. TtC was significantly greater in PF compared to RPF to the anterior boundary during late stance.SignificanceShorter TtC observed in PF compared to the other groups during midstance may indicate reduced dynamic stability during the most stable portion of running which may lead to increased injury risk.  相似文献   
10.
摘 要 目的:评价自制的盐酸溴己新吸入粉雾剂的质量并考察其稳定性。方法: 采用冷冻干燥 气流粉碎法制备盐酸溴己新吸入粉雾剂,考察其吸湿性及临界相对湿度;测定其粒径和水分并观察粉末形态;检查其细微粒子剂量和递送剂量均一性;开展盐酸溴己新吸入粉雾剂稳定性考察。结果:所制备的盐酸溴己新吸入粉雾剂的临界相对湿度为65%,空气动力学粒径<5 μm,粉末含水量<2%,细微粒子剂量>30%,递送剂量均一性符合药典要求;稳定性试验中各指标在观察期内无明显变化。结论:所制备的盐酸溴己新吸入粉雾剂适合肺部吸入给药,且具有较好的稳定性。  相似文献   
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