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Sheridan Goldstein Lupeng Wang Kerry McAlonan Mateus Torres-Cruz Richard J. Krauzlis 《Journal of vision》2022,22(1)
In primates, stimulus-driven changes in visual attention can facilitate or hinder perceptual performance, depending on the location and timing of the stimulus event. Mice have emerged as a powerful model for studying visual circuits and behavior; however, it is unclear whether mice show similar interactions between stimulus events and visual attention during perceptual decisions. To investigate this, we trained head-fixed mice to detect a near-threshold change in visual orientation and tested how performance was altered by task-irrelevant stimuli that occurred at different times and locations with respect to the orientation change. We found that task-irrelevant stimuli strongly affected mouse performance. Specifically, stimulus-driven attention in mice followed a similar time course as that in other species: The decreases in reaction times fully emerged between 250 and 400 ms after the stimulus event, and detection accuracy was not affected. However, the effects of stimulus-driven attention on behavior in mice were insensitive to stimulus-event location, an aspect different from what is known in primates. In contrast, reaction times in mice were reduced at longer delays after the task-irrelevant stimulus event regardless of its spatial congruence to the target. These results highlight the strengths and limitations of using mice as a model for studying higher-order visual functions. 相似文献
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EG Burden RW Walker DJ Ferguson AMF Goubran JR Howell JB John F Khan JS McGrath JP Evans 《Annals of the Royal College of Surgeons of England》2021,103(3):173
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery. 相似文献
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Syncope as the presentation of unstable angina 总被引:1,自引:0,他引:1
A 71-year-old woman presented with syncope in association with unstable angina. Coronary angiography and subsequent postmortem findings demonstrated severe coronary arterial disease. The importance of the association of syncope with unstable angina and possible underlying mechanisms are discussed. 相似文献
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R Bahl DJ Murphy B Strachan 《BJOG : an international journal of obstetrics and gynaecology》2009,116(2):319-326
Objectives The objectives of this study were to define the components of a skilled low-cavity non-rotational vacuum delivery (occiput anterior, vertex at station +2 or below and less than 45-degree rotation from midline) and to facilitate the transfer of skills from expert to trainee obstetricians.
Design Qualitative study using interviews and video recordings.
Setting Two university teaching hospitals (St Michael's Hospital, Bristol, and Ninewell's Hospital, Dundee).
Participants Ten obstetricians and eight midwives identified as experts in conducting or supporting operative vaginal deliveries.
Methods Semi-structured interviews were carried out using routine clinical scenarios. The experts were also video recorded conducting low-cavity vacuum deliveries in a simulation setting. The interviews and video recordings were transcribed verbatim and analysed using thematic coding. The anonymised data were independently coded by three researchers and compared for consistency of interpretation. The experts reviewed the coded interviews and video data for respondent validation and clarification. The themes that emerged following the final coding were used to formulate a list of skills.
Main outcome measures Key technical skills of a low-cavity non-rotational delivery.
Results The final list included detailed technical skills required for conducting a low-cavity vacuum delivery. The combination of semi-structured interviews and simulation videos allowed the formulation of a comprehensive skills tool for future evaluation.
Conclusion This explicitly defined skills list could aid trainees understanding of the technique of low-cavity vacuum delivery. This is an important first step in evaluating clinical competence in intrapartum procedures. 相似文献
Design Qualitative study using interviews and video recordings.
Setting Two university teaching hospitals (St Michael's Hospital, Bristol, and Ninewell's Hospital, Dundee).
Participants Ten obstetricians and eight midwives identified as experts in conducting or supporting operative vaginal deliveries.
Methods Semi-structured interviews were carried out using routine clinical scenarios. The experts were also video recorded conducting low-cavity vacuum deliveries in a simulation setting. The interviews and video recordings were transcribed verbatim and analysed using thematic coding. The anonymised data were independently coded by three researchers and compared for consistency of interpretation. The experts reviewed the coded interviews and video data for respondent validation and clarification. The themes that emerged following the final coding were used to formulate a list of skills.
Main outcome measures Key technical skills of a low-cavity non-rotational delivery.
Results The final list included detailed technical skills required for conducting a low-cavity vacuum delivery. The combination of semi-structured interviews and simulation videos allowed the formulation of a comprehensive skills tool for future evaluation.
Conclusion This explicitly defined skills list could aid trainees understanding of the technique of low-cavity vacuum delivery. This is an important first step in evaluating clinical competence in intrapartum procedures. 相似文献