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排序方式: 共有6985条查询结果,搜索用时 15 毫秒
1.
《Clinical neurophysiology》2021,132(2):315-322
ObjectivePrevious studies have demonstrated voluntary movement alterations as well as motor cortex excitability and plasticity changes in patients with mild cognitive impairment (MCI). To investigate the pathophysiology of movement abnormalities in MCI, we tested possible relationships between movement abnormalities and primary motor cortex alterations in patients.MethodsFourteen amnestic MCI (aMCI) patients and 16 healthy controls were studied. Cognitive assessment was performed using clinical scales. Finger tapping was recorded by a motion analysis system. Transcranial magnetic stimulation was used to test the input/output curve of motor evoked potentials, intracortical inhibition, and short-latency afferent inhibition. Primary motor cortex plasticity was probed by theta burst stimulation. We investigated correlations between movement abnormalities, clinical scores, and cortical neurophysiological parameters.ResultsMCI patients showed less rhythmic movement but no other movement abnormalities. Cortical excitability measures were normal in patients, whereas plasticity was reduced. Movement rhythm abnormalities correlated with frontal dysfunction scores.ConclusionOur study in MCI patients demonstrated abnormal voluntary movement and plasticity changes, with no correlation between the two. Altered rhythm correlated with frontal dysfunction.SignificanceOur results contribute to the understanding of pathophysiological mechanisms of motor impairment in MCI. 相似文献
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Peter H. Egbers Anna-Liisa Sutt Jenny E. Petersson Liza Bergström Eva Sundman 《Acta anaesthesiologica Scandinavica》2023,67(10):1403-1413
Background
Weaning from mechanical ventilation and tracheostomy after prolonged intensive care consume enormous resources with optimal management not currently well described. Restoration of respiratory flow via the upper airway is essential and early cuff-deflation using a one-way valve (OWV) is recommended. However, extended OWV use may cause dry airways and thickened secretions which challenge the weaning process. High-flow therapy via the tracheostomy tube (HFT-T) humidifies inspired air and may be connected via an in-line OWV (HFT-T-OWV) alleviating these problems. We aim to provide clinical and experimental data on the safety of HFT-T-OWV along with a practical guide to facilitate clinical use during weaning from mechanical ventilation and tracheostomy.Methods
Data on adverse events of HFT-T-OWV were retrieved from a quality register for patients treated at an intensive care rehabilitation center between 2019 and 2022. Benchtop experiments were performed to measure maximum pressures and pressure support generated by HFT-T-OWV at 25–60 L/min flow using two different HFT-T adapters (interfaces). In simulated airway obstruction using a standard OWV (not in-line) maximum pressures were measured with oxygen delivered via the side port at 1–3 L/min.Results
Of 128 tracheostomized patients who underwent weaning attempts, 124 were treated with HFT-T-OWV. The therapy was well tolerated, and no adverse events related to the practice were detected. The main reason for not using HFT-T-OWV was partial upper airway obstruction using a OWV. Benchtop experiments demonstrated HFT-T-OWV maximum pressures <4 cmH2O and pressure support 0–0.6 cmH2O. In contrast, 1–3 L/min supplemental oxygen via a standard OWV caused pressures between 84 and 148 cmH2O during simulated airway obstruction.Conclusions
Current study clinical data and benchtop experiments indicate that HFT-T-OWV was well tolerated and appeared safe. Pressure support was low, but humidification may enable extended use of a OWV without dry airway mucosa and thickened secretions. Results suggest the treatment could offer advantages to standard OWV use, with or without supplementary oxygen, as well as to HFT-T without a OWV, for weaning from mechanical ventilation and tracheostomy. However, for definitive treatment recommendations, randomized clinical trials are needed. 相似文献3.
Mayuko Kinoshita Haruka Kaneko Lizu Liu Masashi Nagao Ryo Sadatsuki 《Modern rheumatology / the Japan Rheumatism Association》2019,29(1):157-164
Objectives: To examine the factors associated with increase in lumbar spine bone mineral density (LS-BMD) by bisphosphonates (BPs) with active vitamin D analog (aVD).Methods: Two independent postmenopausal osteoporotic patients treated by BPs with aVD for 24 months (Study 1: n?=?93, Study 2: n?=?99) were retrospectively analyzed.Results: In Study 1, LS-BMD of the patients significantly increased for 24 m (5.4%, p?.001). A multiple regression analysis among baseline characteristics revealed that serum calcium (sCa: 8.5–10.5?mg/dL) was associated with an increased LS-BMD by treatment (r2: 0.088, p?=?.02). While average sCa of the patients was 9.2?mg/dL before treatment, it increased time-dependently to 9.6?mg/dL for 24 m by treatment. As each patient had their LS-BMD five times during the study, there were four instances of %LS-BMD in each patient, resulting in 372 instances of %LS-BMD in Study 1. The smallest Akaike’s information criterion value for the most appropriate cut-off levels of sCa for %LS-BMD by treatment every 6 m was 9.3?mg/dL. The %LS-BMD by treatment for 6 m during 24 m period in patients with sCa ≥9.3?mg/dL (1.5%) was significantly higher than that in patients with sCa <9.3?mg/dL (0.8%, p?=?.038). The results of Study 2 were similar to those of Study 1, confirming the phenomena observed.Conclusion: sCa was associated with an increased LS-BMD by BPs with aVD. 相似文献
4.
Shaghayegh Foroozan‐Broojeni Marziyeh Tavalaee Richard A. Lockshin Zahra Zakeri Homayon Abbasi Mohammad Hossein Nasr‐Esfahani 《Andrologia》2019,51(2)
Abnormal dilatation and tortuosity of the pampiniform plexus within the spermatic cord are termed varicocele which leads to impaired spermatogenesis due to heat‐related oxidative stress and cell death. Previously, it was shown that both apoptosis and autophagy pathways were activated by heat in germ cells of mouse in vivo and in vitro. But, status of these pathways is not clear in chronic state of heat stress such as varicocele. Therefore, we aimed to access sperm apoptotic markers (active caspases 3/7 and DNA fragmentation), and autophagic markers (Atg7 and LC3 proteins) as primary outcomes, and also sperm parameters and protamine deficiency as secondary outcomes between 23 infertile men with varicocele and 16 fertile individuals. Sperm parameters were assessed according to World Health Organization 2010 protocol. Apoptotic markers (active caspases 3/7 and DNA fragmentation), autophagic markers (Atg7 and LC3 proteins), and protamine deficiency were evaluated by flow cytometry, fluorescence microscope, and western blotting techniques. Mean of autophagy and apoptosis markers, and also protamine deficiency have significantly increased in infertile men with varicocele compared to fertile individuals, but autophagy and apoptosis markers did not significantly correlate with each other. In conclusion, it seems that both apoptosis and autophagy pathways are independently active in spermatozoa of infertile men with varicocele. 相似文献
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纳米载体在改善中药有效成分溶解性、生物膜透过性与生物体内行为、增效减毒等方面发挥着重要作用,具有广阔的应用前景。作为新型纳米载体,有机-无机杂化纳米载体由有机和无机材料或载体复合而形成,结合了两者的优势,能够更好地发挥其在药物递送中的作用,提高药物稳定性、载药量和生物相容性,并可以实现多功能化。笔者对近年来国内外中药有效成分有机-无机杂化纳米载体的研究和应用情况进行了总结与分析,并展望其发展前景,可为高效安全递送中药有效成分的新型递药系统的研究提供参考。 相似文献
10.
目的分析化瘀通痹方对活动期类风湿关节炎患者的疗效及患者血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、C反应蛋白(CRP)的变化情况。方法选取2016年8月-2018年8月收治的活动期类风湿关节炎患者104例,根据治疗方法不同分为对照组(西医常规治疗)和观察组(西医常规治疗基础上联合化瘀通痹方治疗),分析两组患者治疗后的临床疗效。结果观察组总有效率为92.31%(48/52),对照组为76.92%(40/52),观察组患者总有效率高于对照组(P<0.05)。两组治疗前症状、体征情况组间比较,差异不具有统计学意义(P>0.05)。观察组治疗后晨僵持续时间短于对照组,关节压痛和关节肿胀积分低于对照组(P<0.05)。两组治疗前TNF-α、IL-1β、CRP、葡萄糖6磷酸异构酶(GPI)、类风湿因子(RF)、血肿瘤坏死因子样配体1A(TL1A)水平组间比较,差异不具有统计学意义(P>0.05)。观察组治疗后TNF-α、IL-1β、CRP、GPI、RF、TL1A水平低于对照组(P<0.05)。两组治疗前28处关节疾病活动度(DAS28)积分组间比较,差异不具有统计学意义(P>0.05)。观察组治疗后DAS28积分低于对照组(P<0.05)。结论化瘀通痹方治疗活动期类风湿关节炎可改善患者临床症状,降低患者TNF-α、IL-1β、CRP、GPI的表达水平,提高疗效。 相似文献