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41.
Background: The ultimate goal in any programme of aphasia rehabilitation is that behaviours targeted in therapy will generalise to everyday use for people with aphasia (PWA). The pervasiveness of conversation in everyday life has undoubtedly contributed to the recent interest in aphasiology regarding how we facilitate, and capture evidence of, change in conversation following therapy. Given the rich nature of conversation data, various analytical approaches have been utilised within impairment-focused therapy studies; however, much of this work has been carried out in isolation from other methodologies such as conversation analysis (CA)—a field which has historically concerned itself with conversation data. The result is a growing literature base which is dispersed in nature. For clinicians who are faced with the daily challenge of therapeutic management for a diverse population of PWA the literature on generalising therapy gains to everyday conversation may be too unwieldy to be of benefit to current clinical practice.

Aims: This paper aims to synthesise and critically review key papers from impairment-focused studies which have investigated the impact of therapy on the conversations of PWA. For the purposes of this review, conversation is defined as a dialogue between the person with aphasia and a conversation partner.

Main Contribution: First, the motivation to investigate conversation within aphasia assessment is discussed, with consideration of how conversation differs from, but ultimately complements, other forms of language assessment. Following this, five impairment therapy studies will provide a platform for discussion of methodological issues and analytical approaches relating to conversation data. Finally, consideration is given to how researchers and clinicians may build on current literature to develop the use of conversation as an outcome measure in aphasia intervention. Where appropriate, insights are drawn from interaction-focused therapy studies regarding the collection and analysis of conversation data.

Conclusions: There is emerging evidence that impairment-focused therapy can impact on the conversations of PWA. While these early findings are promising, investigations have been limited to naming therapies and the methods of data collection used have implications for ecological validity. Incorporating particular elements of interaction-focused approaches may help to inform data collection, investigations of therapy outcome, and issues of candidacy for specific treatments. Furthermore, combining therapeutic and analytical approaches is likely to be more closely akin to the clinical reality of aphasia intervention, where clinicians are likely to use all resources at their disposal in the rehabilitation of a speaker with aphasia.  相似文献   
42.
The intensity of aphasia therapy has been a key clinical question. The aim of this case-series study was to compare the outcome of intensive and non-intensive therapy in the relearning of words for people with aphasia. Eight participants took part in a study comparing the intensity of delivery of the therapy. Participants received two courses of the same therapy (each lasting 10 sessions) delivered either intensively or non-intensively. Therapy consisted of confrontation naming with progressive phonemic and orthographic cues. Post-therapy assessments were carried out immediately after the study and one month later. Performance was also monitored during each therapy session. Immediately post-therapy, both types of therapy had improved naming accuracy considerably and there was no significant difference between the two interventions. One month later, seven out of eight participants showed a small yet significant difference in naming accuracy, favouring non-intensive over intense therapy. There were no differences in the learning patterns during the therapy sessions between the intensive and non-intensive therapies. For the majority of people with aphasia post-stroke, both intense and non-intense therapy for anomia leads to improved naming performance. Retention at one-month post therapy is relatively superior after non-intensive therapy.  相似文献   
43.
To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD.  相似文献   
44.
Successful adaptation to novel sensorimotor contexts critically depends on efficient sensory processing and integration mechanisms, particularly those required to combine visual and proprioceptive inputs. If the basal ganglia are a critical part of specialized circuits that adapt motor behavior to new sensorimotor contexts, then patients who are suffering from basal ganglia dysfunction, as in Parkinson's disease should show sensorimotor learning impairments. However, this issue has been under-explored. We tested the ability of 8 patients with Parkinson's disease (PD), off medication, ten healthy elderly subjects and ten healthy young adults to reach to a remembered 3D location presented in an immersive virtual environment. A multi-phase learning paradigm was used having four conditions: baseline, initial learning, reversal learning and aftereffect. In initial learning, the computer altered the position of a simulated arm endpoint used for movement feedback by shifting its apparent location diagonally, requiring thereby both horizontal and vertical compensations. This visual distortion forced subjects to learn new coordinations between what they saw in the virtual environment and the actual position of their limbs, which they had to derive from proprioceptive information (or efference copy). In reversal learning, the sign of the distortion was reversed. Both elderly subjects and PD patients showed learning phase-dependent difficulties. First, elderly controls were slower than young subjects when learning both dimensions of the initial biaxial discordance. However, their performance improved during reversal learning and as a result elderly and young controls showed similar adaptation rates during reversal learning. Second, in striking contrast to healthy elderly subjects, PD patients were more profoundly impaired during the reversal phase of learning. PD patients were able to learn the initial biaxial discordance but were on average slower than age-matched controls in adapting to the horizontal component of the biaxial discordance. More importantly, when the biaxial discordance was reversed, PD patients were unable to make appropriate movement corrections. Therefore, they showed significantly degraded learning indices relative to age-matched controls for both dimensions of the biaxial discordance. Together, these results suggest that the ability to adapt to a sudden biaxial visuomotor discordance applied in three-dimensional space declines in normal aging and Parkinson disease. Furthermore, the presence of learning rate differences in the PD patients relative to age-matched controls supports an important contribution of basal ganglia-related circuits in learning novel visuomotor coordinations, particularly those in which subjects must learn to adapt to sensorimotor contingencies that were reversed from those just learned.  相似文献   
45.
The concept of an Ecological Approach to health and including Health in All Policies warrants inter-sectoral and transdisciplinary collaboration to improve health determinants and reduce health inequities. Agriculture policies, which greatly influence food production and its environmental impacts as well as food availability and dietary consumption, are therefore of interest to public health. Increasing rates of non-communicable diseases linked to diets containing high levels of processed foods, increasing numbers of households unable to access nutritious food and the environmental consequences of the food system are amongst the major health challenges of today, both globally and in Ireland. In 2010, Ireland’s Department of Agriculture, Food and Fisheries published Food Harvest 2020 a roadmap for Irish agriculture for the subsequent decade prepared against a backdrop of rising diet-related ill-health and increasing environmental concerns. This article critically analyses the process of consultation and stakeholder involvement in the development of Food Harvest 2020 from a public health perspective. Publically available documents including submissions to the Food Harvest 2020 consultation process were the primary source of data. This study highlights a distinct absence of public health representation in the process, an avoidance of some key public health challenges and the dominance of a ‘business as usual’ approach.  相似文献   
46.
47.
α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价   总被引:4,自引:0,他引:4  
目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。  相似文献   
48.
Due to the changes in delivering medical care during the Coronavirus disease 2019 (COVID‐19) pandemic, such as the heavy reliance on telehealth, it is worth exploring if this is suitable when treating complex wounds. A literature rapid review was performed to explore the existing evidence around alternative service delivery modalities. While there are organisations that have successful telehealth systems and infrastructure, for services that do not already widely use telehealth it is difficult to implement a standardised system in the current state of emergency. The evidence reviewed demonstrates that telehealth appears to currently have a limited place in chronic wound management; therefore, standardisation on determining suitability in conjunction with evaluation of telehealth during this period is needed to shape implementation of telehealth systems in the future.  相似文献   
49.
PURPOSE: This study was designed to test the hypothesis that the extent of anal sphincter muscle injury as graded at endosonography correlates with the degree of functional impairment. METHODS: Three hundred and thirty adults presenting for evaluation of fecal incontinence were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Anal sphincter muscle tears were graded on the basis of the degree of circumferential involvement (< or >25 percent) and by an assessment of the superoinferior longitudinal extent of an external anal sphincter tear. Muscles that demonstrated multiple tears, poor visualization, or fragmentation were classed as fragmented. Sphincter injuries were correlated with basal and squeeze pressures at manometry, pudendal nerve terminal latencies, and the severity of symptoms using the Parks-Browning clinical score. RESULTS: Patients with an intact external anal sphincter had a higher squeeze pressure (mean, 162.6 cm H(2)O) than those with a partial- (mean, 125.7 cm H(2)O) or full-length tear (mean, 124.9 cm H(2)O; P < 0.0001). There was no significant difference in squeeze pressure between those with partial- vs. full-length external anal sphincter tears nor between circumference tears < or >25 percent. Basal pressure was significantly lower in those with a full-length external anal sphincter tear (47.8 cm H(2)O) vs. an intact external anal sphincter (65.7 cm H(2)O; P < 0.001). The basal pressure in those with an intact internal anal sphincter was not significantly different from those with clearly defined internal anal sphincter tears, and the degree of circumferential involvement was also not important in this regard. However, those with a fragmented internal anal sphincter had a significantly lower basal pressure than other subgroups of internal anal sphincter injuries (P < 0.001). There was no association between external or internal anal sphincter status and the mean pudendal nerve terminal motor latency, suggesting the patient groups were neurologically similar. There was no significant association between external or internal anal sphincter status and the severity of reported symptoms. CONCLUSION: Correlations between the presence or absence of muscle tears and reduced manometric function have been identified. Further grading of tears was of less importance. No relationship between muscle injuries and the severity of clinical symptoms could be elicited.  相似文献   
50.
The ovary as a source of alpha-ecdysone in an adult mosquito.   总被引:2,自引:1,他引:2       下载免费PDF全文
The ovaries of the mosquito Aedes aegypti cultured in vitro secrete material that behaves like ecdysone in a radioimmunoassay. The material was identified as alpha-ecdysone by high-resolution liquid and gas-liquid chromatography. Secretion reached a maximum 16 hr after a blood meal as shown by bioassay and direct determination. Ovariectomy reduced the concentration of ecdysone in the adult after a blood meal. Qualitative analysis of whole-body extracts indicated beta-ecdysone to be the principal species present. Thus the ovaries appear to secrete a prohormone, alpha-ecdysone, which is converted to beta-ecdysone. Beta-ecdysone plays a significant role in stimulating egg development in the adult mosquito and may have reproductive roles in other insects.  相似文献   
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