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41.
Deficits in task switching can be found after frontal lobe damage. Here we demonstrate an impairment in task switching specifically linked to when perceptual weights have to be moved between different dimensions of the same stimulus. A patient (DS) with left frontal lobe damage showed normal performance when he responded to the meaning (a word task) or location (a location task) of a word presented to the left or right of fixation when there was no switching between the tasks. However, when the two tasks were switched every 16 trials in a block, DS showed severe difficulty in performing both tasks (Experiment 1). There were then abnormally large switch costs and effects of stimulus-response congruency. The difficulty was not simply due to switching tasks per se: There were no costs of switching when one of the tasks was modified to have different stimulus displays from the other (Experiment 2). The deficit was also not greater when the switch had to be made from a well-practised task to an unpractised task with more arbitrary stimulus-response mappings, indicating no particular problem in disengaging from a learned task or in configuring new stimulus-response links (Experiment 4). We suggest instead that DS was impaired at shifting attentional weights across different dimensions of the same stimulus, a process required with practised and unpractised tasks alike. The results link this process of shifting attention across stimulus dimensions to the left frontal lobe.  相似文献   
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We contrast naming from pictures, and reading words, for objects and verbs (actions relating to the objects) in a patient with a large, posterior left-hemisphere lesion. We present evidence for spared picture naming for verbs relative to objects, whilst the opposite pattern of sparing occurred in reading. Objects were also spared relative to verbs in tasks requiring that written words be matched to either pictures or auditory words, in the presence of semantically related or unrelated distractors. We conclude that verb semantics were more impaired than semantic knowledge for objects, and that the better semantic knowledge for object names supported word reading. With pictures, however, action verb retrieval was maintained through a nonsemantic route from vision to action, or though preserved right-hemisphere "action semantics."  相似文献   
45.
Ruptures of the anterior cruciate ligament (ACL) are common knee injuries that do not heal, even with surgical repair. Our research is directed towards developing novel, biological approaches that enable suture repair of this ligament. One promising strategy involves the insertion of a collagen hydrogel between the severed ends of the ACL. Cells migrate from the damaged ligament into the hydrogel and produce repair tissue. Here we have investigated the potential for augmenting this process by the transfer of insulin like growth factor (IGF) 1 cDNA to the repair cells using an adenovirus vector. The goal is to achieve direct, in situ gene delivery by loading the hydrogel with vector prior to its insertion into the defect. In a step-wise approach towards evaluating this process, we confirmed that monolayers of ACL fibroblasts were efficiently transduced by adenovirus vectors and continued to express transgenes when subsequently incorporated into the hydrogel; indeed, transgene expression persisted longer within collagen gels than in monolayer culture. Transfer of IGF-1 cDNA increased the cellularity of the gels and led to the synthesis and deposition of increased amounts of types I and III collagen, elastin, tenascin, and vimentin. The cells remained viable, even when subjected to high viral loads. Similar results were obtained when collagen hydrogels were preloaded with adenovirus prior to insertion into an experimental ACL lesion in vitro. These data confirm the promise of using vector-laden hydrogels for the in situ delivery of genes to cells within damaged ligaments and suggest novel possibilities for the biological repair of the ACL.  相似文献   
46.

Objective

To develop a framework of decision making and coping in healthcare that describes the twin processes of appraisal and coping faced by patients making preference-sensitive healthcare decisions.

Methods

We briefly review the literature for decision making theories and coping theories applicable to preference-sensitive decisions in healthcare settings. We describe first decision making, then coping and finally attempt to integrate these processes by building on current theory.

Results

Deliberation in healthcare may be described as a six step process, comprised of the presentation of a health threat, choice, options, preference construction, the decision itself and consolidation post-decision. Coping can be depicted in three stages, beginning with a threat, followed by primary and secondary appraisal and ultimately resulting in a coping effort.

Conclusions

Drawing together concepts from prominent decision making theories and coping theories, we propose a multidimensional, interactive framework which integrates both processes and describes coping in deliberation.

Practice implications

The proposed framework offers an insight into the complexity of decision making in preference-sensitive healthcare contexts from a patient perspective and may act as theoretical basis for decision support.  相似文献   
47.

Background

Current models of the medical consultation emphasize shared decision-making (SDM), whereby the expertise of both the doctor and the patient are recognised and seen to equally contribute to the consultation. The evidence regarding the desirability and effectiveness of the SDM approach is often conflicting. It is proposed that the conflicts are due to the nature of assessment, with current assessments from the perspective of an outside observer.

Aims

To empirically assess perceived involvement in the medical consultation using the dyadic OPTION instrument.

Method

36 simulated medical consultations were organised between general practitioners and standardized- patients, using the observer OPTION and the newly developed dyadic OPTION instruments.

Results

SDM behaviours observed in the consultations were seen to depend on both members of the doctor and patient dyad, rather than each in isolation. Thus a dyadic approach to measurement is supported.

Conclusions

This current study highlights the necessity for a dyadic approach to assessment and introduces a novel research instrument: the dyadic OPTION instrument.  相似文献   
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Vaccination of cattle with a commercial human tuberculosis (TB) vaccine, Mycobacterium bovis bacillus Calmette-Guérin (BCG) Danish, at a dose equivalent to 5 human doses of BCG has protected these animals against TB in field and experimental trials. There is interest in determining whether a 10-fold-lower dose could still protect cattle but not induce a tuberculin intradermal test response. Two groups of calves (n = 9/group) were vaccinated subcutaneously with a lyophilized BCG Danish vaccine containing either 0.5 (1 × 105 to 4 × 105 CFU) or 5 (1 × 106 to 4 × 106 CFU) human doses of BCG Danish, with an additional group of 10 calves serving as nonvaccinated controls. Fifteen weeks after vaccination, these animals were challenged intratracheally with 5 × 103 CFU of virulent M. bovis and another 15 weeks later were slaughtered and examined for the presence of tuberculous lesions. Vaccination of the calves with either 0.5 or 5 equivalent human doses of BCG Danish induced similar levels of protection against challenge with M. bovis, with both groups showing significant reductions in the pathological and microbiological parameters compared to those for the the control group (P < 0.05). Vaccination with either of the two BCG doses induced similar numbers of animals responding to the tuberculin intradermal test at 11 weeks postvaccination. Vaccination with a 0.5 equivalent human dose of a commercial lyophilized BCG vaccine can protect cattle against challenge with M. bovis.  相似文献   
50.

Objective

To describe the exploratory use of short decision support tools for patients, called Option Grids. Option Grids are summary tables, using one side of paper to enable rapid comparisons of options, using questions that patients frequently ask (FAQs) and designed for face-to-face clinical encounters. To date, most evidence about ‘patient decision aids’ has been based on tools with high content levels, designed for patients to use independently, either before or after visits.

Methods

We studied the use of Option Grids in a quality improvement project, collecting field notes and conducting interviews with clinical teams.

Results

In the ‘Making Good Decisions in Collaboration’ (MAGIC) program, clinicians found that using Option Grids made it easier to explain the existence of options and reported a ‘handover’ effect, where patient involvement in decision making was enhanced.

Conclusion

Option Grids made options more visible and clinicians found it easier to undertake shared decision making when these tools were available. Used in a collaborative way, they enhance patients’ confidence and voice, increasing their involvement in collaborative dialogs.

Practice implications

Further work to confirm these preliminary findings is required, to measure processes and to assess whether these tools have similar impact in other clinical settings.  相似文献   
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