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51.
Eight bibenzyl derivatives, namely dendrocandins J–Q (1–8), were isolated from the stems of Dendrobium candidum. Their structures were elucidated by 1D and 2D NMR experiments and mass spectrometry. Compounds 1–8 were examined for antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay, and the IC50 values were 36.8, 70.2, 45.0, 60.5, 87.6, 50.4, 22.3, and 30.3 μM, respectively. 相似文献
52.
《Gait & posture》2017
Online gait corrections are frequently used to restore gait stability and prevent falling. They require shorter response times than voluntary movements which suggests that subcortical pathways contribute to the execution of online gait corrections. To evaluate the potential role of the cerebellum in these pathways we tested the hypotheses that online gait corrections would be less accurate in individuals with focal cerebellar damage than in neurologically intact controls and that this difference would be more pronounced for shorter available response times and for short step gait corrections. We projected virtual stepping stones on an instrumented treadmill while some of the approaching stepping stones were shifted forward or backward, requiring participants to adjust their foot placement. Varying the timing of those shifts allowed us to address the effect of available response time on foot placement error. In agreement with our hypothesis, individuals with focal cerebellar lesions were less accurate in adjusting their foot placement in reaction to suddenly shifted stepping stones than neurologically intact controls. However, the cerebellar lesion group’s foot placement error did not increase more with decreasing available response distance or for short step versus long step adjustments compared to the control group. Furthermore, foot placement error for the non-shifting stepping stones was also larger in the cerebellar lesion group as compared to the control group. Consequently, the reduced ability to accurately adjust foot placement during walking in individuals with focal cerebellar lesions appears to be a general movement control deficit, which could contribute to increased fall risk. 相似文献
53.
《Nurse education in practice》2014,14(2):220-224
The international world of higher education is changing with universities now offering students flexible delivery options that allow them to study away from campus and at a time convenient to them. Some students prefer on line learning while others prefer face to face contact offered through a traditional lecture and tutorial delivery modes. The response by many universities is to offer a blend of both. While online and blended mode of delivery may be suitable for some subjects there is little knowledge of the efficacy of blended learning models to teach evidence based practice and research (EBPR) to undergraduate midwifery students. EBPR is a challenging, threshold level subject upon which deeper knowledge and skills are built. This paper describes the design, delivery, and evaluation of an undergraduate EBPR course delivered in blended mode to first year midwifery students. Components of the blended learning innovation included: novel teaching strategies, engaging practical activities, role play, and e-learning strategies to maintain engagement. University-based course evaluation outcomes revealed very positive scores and the course was rated within the top ten percent of all courses offered within the Health Group at the host University. 相似文献
54.
《Patient education and counseling》2017,100(2):183-189
ObjectiveConsidering the status of the Internet as a prominent source of health information, assessing online health material has become a central issue in patient education. We describe the strategies available to evaluate the characteristics of online health information, including readability, emotional content, understandability, usability.MethodsPopular tools used in assessment of readability, emotional content and comprehensibility of online health information were reviewed. Tools designed to evaluate both printed and online material were considered.ResultsReadability tools are widely used in online health material evaluation and are highly covariant. Assessment of emotional content of online health-related communications via sentiment analysis tools is becoming more popular. Understandability and usability tools have been developed specifically for health-related material, but each tool has important limitations and has been tested on a limited number of health issues.ConclusionDespite the availability of numerous assessment tools, their overall reliability differs between readability (high) and understandability (low). Approaches combining multiple assessment tools and involving both quantitative and qualitative observations would optimize assessment strategies.Practice implicationsEffective assessment of online health information should rely on mixed strategies combining quantitative and qualitative evaluations. Assessment tools should be selected according to their functional properties and compatibility with target material. 相似文献
55.
Typically, health policy, practice and research views alcohol and other drug (AOD) ‘problems’ as objective things waiting to be detected, diagnosed and treated. However, this approach to policy development and treatment downplays the role of clinical practices, tools, discourses, and systems in shaping how AOD use is constituted as a ‘problem’. For instance, people might present to AOD treatment with multiple psycho-social concerns, but usually only a singular AOD-associated ‘problem’ is considered serviceable. As the assumed nature of ‘the serviceable problem’ influences what treatment responses people receive, and how they may come to be enacted as ‘addicted’ or ‘normal’ subjects, it is important to subject clinical practices of problem formulation to critical analysis. Given that the reach of AOD treatment has expanded via the online medium, in this article we examine how ‘problems’ are produced in online alcohol counselling encounters involving people aged 55 and over. Drawing on poststructural approaches to problematisation, we not only trace how and what ‘problems’ are produced, but also what effects these give rise to. We discuss three approaches to problem formulation: (1) Addiction discourses at work; (2) Moving between concerns and alcohol ‘problems’; (3) Making ‘problems’ complex and multiple. On the basis of this analysis, we argue that online AOD counselling does not just respond to pre-existing ‘AOD problems’. Rather, through the social and clinical practices of formulation at work in clinical encounters, online counselling also produces them. Thus, given a different set of circumstances, practices and relations, ‘problems’ might be defined or emerge differently—perhaps not as ‘problems’ at all or perhaps as different kinds of concerns. We conclude by highlighting the need for a critical reflexivity in AOD treatment and policy in order to open up possibilities for different ways of engaging with, and responding to, people’s needs in their complexity. 相似文献
56.
《Clinical neurophysiology》2021,132(8):1845-1849
ObjectivePatients with myasthenia gravis associated with muscle-specific tyrosine kinase antibodies (MuSK-MG) often manifest signs of cholinergic hyperactivity with standard doses of acetylcholinesterase inhibitors (AChE-Is). Aim of the study was to investigate whether repetitive compound muscle action potential (R-CMAP), the neurophysiological correlate of cholinergic hyperactivity, was present in MuSK-MG irrespective of AChE-I treatment.MethodsPatients with confirmed diagnosis of MuSK-MG were consecutively enrolled during follow-up visits, from January 2019 to April 2020. All these subjects underwent the same neurophysiological protocol, including motor nerve conduction studies and repetitive nerve stimulation. In patients taking pyridostigmine, neurophysiological testing was performed at least 12 hours after the last dose. For comparison, the presence of R-CMAP was investigated in 20 consecutive acetylcholine receptor antibody positive myasthenia gravis (AChR-MG) patients.ResultsWe enrolled 25 MuSK-MG patients (20 females), aged 16–79 years at the study time, with disease duration ranging 0.6–48.8 years (median: 17.7 years). R-CMAP was detected in 12/25 (48%) MuSK-MG cases and in none of the AChR-MG controls (p = 0.0003). In the MuSK-MG population, a history of muscle cramps and fasciculations, during low-dose pyridostigmine therapy, was significantly more frequent in R-CMAP positive than in R-CMAP negative patients (100% vs 31%, p = 0.001). At the time of the study, the proportion of patients still symptomatic for MG was higher among R-CMAP positive cases (92% vs 23%, p = 0.0005).ConclusionsCholinergic hyperactivity is a relatively common finding in MuSK-MG patients, independent of AChE-I treatment, and may constitute an intrinsic feature of the disease.SignificanceR-CMAP detection can represent a useful diagnostic clue for MuSK-MG and predicts poor tolerance to AChE-Is. 相似文献
57.
58.
《Scandinavian journal of occupational therapy》2013,20(4):377-384
AbstractLife balance seems subjective, health related, and multidimensional. However, the concept is complex. Exploring what people themselves consider more or less important for their life balance and whether this differs between people would develop new knowledge. Q methodology was chosen for the present study, in which 32 working men and women without recent long-term sick leave participated. They sorted 42 statements regarding life balance according to their importance for each participant's life balance. The analysis resulted in four different viewpoints concerning life balance. All four viewpoints considered good relationships with those closest to them, as well as knowing that these people were doing well, as important. Each viewpoint also showed a unique orientation towards what was considered important for life balance: occupational balance (viewpoint 1), self-actualization (viewpoint 2), self-awareness (viewpoint 3), and reciprocal relationships (viewpoint 4). The results. showed support for life balance as being a subjective, multidimensional, and health-related phenomenon. The results demonstrated the importance of relationships for life balance and heterogeneity in what people considered important for their own life balance. 相似文献
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