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1.
BackgroundA venous leg ulcer is a chronic leg wound caused by poor venous blood circulation in the lower limbs. It is a recurring condition causing pain, malodour, reduced mobility, and depression. Randomised controlled trials evaluating treatments for venous leg ulcers provide important evidence to inform clinical decision-making. However, for findings to be useful, outcomes need to be clinically meaningful, consistently reported across trials, and fully reported. Research has identified the large number of outcomes reported in venous leg ulcer trials, impacting both synthesis of results, and clinical decision-making. To address this, a core outcome set will be developed. A core outcome set is an agreed standardised set of outcomes which should be, as a minimum, measured and reported in all trials which evaluate treatment effectiveness for a given indication. A core outcome set has the potential to reduce research waste, improve the utility of RCTs, reduce reporting bias, facilitate treatment comparisons across different sources of evidence and expedite the production of systematic reviews, meta-analyses and evidence-based clinical guidelines.AimThe aim of this project is to develop a core outcome set for research evaluating the effectiveness of interventions for treating venous leg ulceration.MethodsThrough a scoping review of the literature on venous leg ulceration, we will firstly identify a list of candidate outcome domains (broad categories in relation to what is being measured) from randomised controlled trials and qualitative research, and outcomes (specific methods in relation to what is being measured). In two further stages, we will use the resulting lists of outcome domains and outcomes to design two online surveys. A range of stakeholders will be invited to participate in the surveys and they will be asked to indicate which outcome domains and outcomes are most important and should be considered as core in future research reports.  相似文献   
2.
《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
3.
目的:观察核心结合因子a1(Cbfa1)对兔骨髓间充质干细胞(MSCs)向成骨细胞分化的诱导作用。方法:体外分离培养兔骨髓MSCs,用AdEasy1/Cbfa1。转染MSCs,在转染后3d,1、2、3和4周时,组织化学和免疫组化等方法检测成骨标志碱性磷酸酶和骨钙素的表达。结果:AdEasy1/Cbfa1转染后的兔骨髓MSCs表现出与成骨细胞相似的形态,并且表达碱性磷酸酶和骨钙素。结论:Cbfa1可诱导兔骨髓MSCs向成骨细胞分化。  相似文献   
4.
Decorin, a collagen-binding small proteoglycan, is considered to have a specific function in the organization or stability of the collagen network. Therefore, alteration of its molecular properties may be of pathophysiological relevance during the development of cartilage damage. It is shown here that normal cartilage from rabbit knee-joint contains glycosaminoglycan chain-bearing core protein fragments of 39, 23, and 18 kDa, each one amounting to approximately 5-6% of the intact decorin core protein. Continuous infusion of human recombinant interleukin-1 alpha for 14 days (200 ng/day) into a knee-joint led in condylar cartilage to a reduction in the amount of intact core protein from 2 micrograms/mg wet tissue to about 1.1 micrograms/mg. The increase in its quantity found after infusion of heat-inactivated interleukin-1 was not statistically significant. The concentration of all three core protein fragments became reduced to a similar extent as the intact core protein under the influence of the cytokine, and additional fragments were not found. Surprisingly, there was a much smaller response to interleukin-1-treatment in patellar cartilage.  相似文献   
5.
背景 针灸是治疗慢性非特异性腰痛(CNSLBP)的重要方法。随着研究的发展,大量针灸治疗CNSLBP的随机对照试验(RCT)已经发表,但由于在结局指标选择方面存在一定的问题,严重限制了高质量临床证据的产生。目的 评价针灸治疗CNSLBP RCT选用的结局指标情况,为针灸治疗CNSLBP相关研究提供参考依据。方法 系统检索4个中文数据库(中国知网、维普网、万方数据知识服务平台、中国生物医学文献服务系统)、3个英文数据库(PubMed、Embase、Cochrane Library)2017-01-01至2022-03-15发布的针灸治疗CNSLBP的文献,以及自建库以来至2022-03-15发表的非特异性腰痛(NSLBP)的核心结局指标集(COS)。对纳入的针灸治疗CNSLBP的文献基本特征进行分析,对文献的临床结局指标进行归类,对文献中的结局指标及《中医病证诊断疗效标准》的应用现状进行分析。分析NSLBP研究的COS现状,比较其与现有针灸治疗CNSLBP文献结局指标的异同。结果 本研究纳入的针灸治疗CNSLBP的49篇文献均为RCT,共包含4篇英文文献和45篇中文文献。共包含4 272...  相似文献   
6.
探讨髓芯减压联合血管内皮生长因子(VEGF)与胶原基骨移植材料对兔股骨头缺血坏死的修复作用。方法 对24只SPF级家兔股骨头内注射无水乙醇建立兔股骨头坏死模型,然后将家兔随机分为模型对照组(A组)、髓芯减压+自体松质骨组(B组)、髓芯减压+胶原基骨修复材料组(C组)和髓芯减压+胶原基骨修复材料+VEGF组(D组),每组6只,共治疗12周。通过苏木精伊红(HE)染色观察组织切片形态。采用骨密度分析系统(QCT PRO V6.1)测量家兔股骨头骨密度(BMD)。Western blot检测VEGF、Collagen I、Runt相关转录因子2(RUNX2)、骨钙素(OCN)、Wnt-3a、β-catenin和GSK-3β的蛋白表达。结果 术后12周时,与B、C组比较,D组家兔股骨头骨小梁排列较整齐,骨髓中观察到大量微血管的形成,可见明显成骨,且坏死区基本被修复。与A组相比,B组、C组和D组家兔股骨头空骨陷窝比率均显著降低(P<0.05);D组家兔股骨头空骨陷窝比率小于B组和C组(P<0.05)。与A组相比,B组、C组和D组家兔股骨头的骨密度均显著升高(P<0.05);D组骨密度显著高于B组和C组(P<0.05)。与B组和C组相比,D组VEGF、Collagen I、RUNX2和OCN的蛋白表达水平均显著升高(P<0.05);与B组和C组相比,D组Wnt-3a和β-catenin的蛋白表达水平均显著升高,GSK-3β的蛋白表达水平显著降低(P<0.05)。结论 髓芯减压联合VEGF与胶原基骨移植材料对兔股骨头缺血坏死可有效促进坏死股骨头的修复,提高骨密度及成骨蛋白的表达  相似文献   
7.
8.
It is yet unknown how upper body exercise combined with high ambient temperatures affects plasma testosterone and cortisol concentrations and furthermore, how these hormones respond to exercise in people suffering spinal cord injuries. The purpose of this study was to characterize plasma testosterone and cortisol responses to upper body exercise in wheelchair athletes (WA) compared to able-bodied individuals (AB) at two ambient temperatures. Four WA [mean age 36 (SEM 13) years, mean body mass 66.9 (SEM 11.8) kg, injury level T7–T11], matched with five AB [mean age 33.4 (SEM 8.9) years, mean body mass 72.5 (SEM 13.1) kg] exercised (cross-over design) for 20 min on a wheelchair ergometer (0.03 kg resistance · kg−1 body mass) at 25 °C and 32 °C. Blood samples were obtained before (PRE), at min 10 (MID), and min 20 (END) of exercise. No differences were found between results obtained at 25 °C and 32 °C for any physiological variable studied and therefore these data were combined. Pre-exercise testosterone concentration was lower (P < 0.05) in WA [18.3 (SEM 0.9) nmol · l−1] compared to AB [21.9 (SEM 3.6) nmol · l−1], and increased PRE to END only in WA. Cortisol concentrations were similar between groups before and during exercise, despite higher rectal temperatures in WA compared to AB, at MID [37.21 (SEM  0.14) and 37.02 (SEM  0.08)°C, respectively] and END [37.36 (SEM 0.16) and 37.19 (SEM 0.10)°C, respectively]. Plasma norepinephrine responses were similar between groups. In conclusion, there were no differences in plasma cortisol concentrations, which may have been due to the low relative exercise intensities employed. The greater exercise response in WA for plasma testosterone should be confirmed on a larger population. It could have been the result of the lower plasma testosterone concentrations at rest in our group. Accepted: 4 September 2000  相似文献   
9.
Summary Six trained male cyclists and six untrained but physically active men participated in this study to test the hypothesis that the use of percentage maximal oxygen consumption (% , as a normalising independent variable is valid despite significant differences in the absolute of trained and untrained subjects. The subjects underwent an exercise test to exhaustion on a cycle ergometer to determine and lactate threshold. The subjects were grouped as trained (T) if their exceeded 60 ml ·kg–1 ·min–1, and untrained (UT) if their was less than 50 ml · kg–1 · min-–1. The subjects were required to exercise on the ergometer for up to 40 min at power outputs that corresponded to approximately 50% and 70% The allocation of each exercise session (50% or 70% was random and each session was separated by at least 5 days. During these tests venous blood was taken 10 min before exercise (–10 min), just prior to the commencement of exercise (–10 min), after 20 min of exercise (20 min), at the end of exercise and 10 min postexercise (+ 10 min) and analysed for concentrations of cortisol, [Na+], [K+], [CI], glucose, free fatty acid, lactate [la-], [NH3], haemoglobin [Hb] and for packed cell volume. The oxygen consumption ( ) and related variables were measured at two time intervals (14–15 and 34–35 min) during the prolonged exercise tests. Rectal temperature was measured throughout both exercise sessions. There was a significant interaction effect between the level of training and exercise time at 50% for heart rate ( c:) and venous [la]. At 70% and ventilation ( ) for the T group and and carbon dioxide production for the UT group increased significantly with time and there was a significant interaction effect forf c, ]Ia–1], [Hb] and [NH3]. The change in body mass at 50% and 70% was significantly greater in the T group. The present study found that when two groups of male subjects with different absolute exercised at a similar percentage of some effector responses were significantly different, questioning the validity of selecting % as a normalising independent variable.  相似文献   
10.
Polycythaemia has been shown to improve physical performance, possibly due to increased arterial oxygen transport. Enhanced thermoregulatory function may also accompany this manipulation, since a greater proportion of the cardiac output becomes available for heat dissipation. We further examined this possibility in five trained men, who participated in three-phase heat stress trials (20 min rest, 20 min cycling at 30% peak power Wpeak and 20 min at 45% Wpeak at 38.3 (SEM 0.7)°C [relative humidity 41.4 (SEM 2.9)%]. Trials were performed during normocythaemia (control) and polycythaemia, obtained by reinfusion of autologous red blood cells and resulting in significant elevation of arterial oxygen transport. During the polycythaemic trials, the subjects demonstrated diminished thermal strain, as evidenced by a significant reduction in cardiac frequency (f c: 12 beats · min–1 lower throughout the test;P < 0.05), and reduced auditory canal temperatures (T ae) during the latter 20-min phase (P < 0.05). Forearm sweat onset was more rapid (363.0 compared to 1083.0 s;P < 0.05), and forearm sweat rate (. msw) sensitivity was elevated from 1.80 to 2.91 · mg · cm–2 · min–1 · °C–1 (P < 0.05). Foreheadm sw was depressed during the final 20 min, while forearmm sw was greater during all test phases, averaging 0.94 and 1.20 mg · cm–2 · min–1, respectively, over the 60 min. Skin blood flows for the upper back, upper arm and forearm were reduced (P < 0.05). Polycythaemia enhanced thermoregulation, through an elevation in forearm sweat sensitivity and.m sw, but not via increased cutaneous blood flow. These modifications occurred simultaneously with decreases inf c andT ae, resulting in greater thermal tolerance.  相似文献   
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