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61.
Elliott H. Myrowitz 《Saudi Journal of Ophthalmology》2012,26(3):293-297
The development and progression of early onset myopia is actively being investigated. While myopia is often considered a benign condition it should be considered a public health problem for its visual, quality of life, and economic consequences. Nearly half of the visually impaired population in the world has uncorrected refractive errors, with myopia a high percent of that group. Uncorrected visual acuity should be screened for and treated in order to improve academic performance, career opportunities and socio-economic status.Genetic and environmental factors contribute to the onset and progression of myopia. Twin studies have supported genetic factors and research continues to identify myopia genetic loci. While multiple myopia genetic loci have been identified establishing myopia as a common complex disorder, there is not yet a genetic model explaining myopia progression in populations.Environmental factors include near work, education levels, urban compared to rural location, and time spent outdoors. In this field of study where there continues to be etiology controversies, there is recent agreement that children who spend more time outdoors are less likely to become myopic.Worldwide population studies, some completed and some in progress, with a common protocol are gathering both genetic and environmental cohort data of great value. There have been rapid population changes in prevalence rates supporting an environmental influence.Interventions to prevent juvenile myopia progression include pharmacologic agents, glasses and contact lenses. Pharmacological interventions over 1–2 year trials have shown benefits. Peripheral vision defocus has been found to affect the emmetropization process and may be affected by wearing glasses or contacts. Accommodation accuracy also has been implicated in myopia progression.Further research will aim to assess both the role and interaction of environmental influences and genetic factors. 相似文献
62.
The Effects of Fatigue From Overnight Shifts on Radiology Search Patterns and Diagnostic Performance
《Journal of the American College of Radiology》2018,15(12):1709-1716
PurposeThe aim of this study was to assess the effect of overnight shifts (ONS) on radiologist fatigue, visual search pattern, and diagnostic performance.MethodsThis experimental study was approved by the institutional review board. Twelve radiologists (five faculty members and seven residents) each completed two sessions: one during a normal workday (“not fatigued”) and another in the morning after an ONS (“fatigued”). Each radiologist completed the Swedish Occupational Fatigue Inventory. During each session, radiologists viewed 20 bone radiographs consisting of normal and abnormal findings. Viewing time, diagnostic confidence, and eye-tracking data were recorded.ResultsSwedish Occupational Fatigue Inventory results demonstrated worsening in all five variables (lack of energy, physical exertion, physical discomfort, lack of motivation, and sleepiness) after ONS (P < .01). Overall, participants demonstrated worse diagnostic performance in the fatigued versus not fatigued state (P < .05). Total viewing time per case was longer when fatigued (35.9 ± 25.8 seconds) than not fatigued (24.8 ± 16.3 seconds) (P < .0001). Total viewing time per case was longer for residents (P < .05). Mean total fixations generated during the search increased by 60% during fatigued sessions (P < .0001). Mean time to first fixate on the fracture increased by 34% during fatigued sessions (P < .0001) and was longer for residents (P < .01). Dwell times associated with true- and false-positive decisions increased, whereas those with false negatives decreased.ConclusionsAfter ONS, radiologists were more fatigued with worse diagnostic performance, a 45% increase in view time per case, a 60% increase in total gaze fixations, and a 34% increase in time to fixate on the fracture. The effects of fatigue were more pronounced in residents. 相似文献
63.
Giorgia Del Favero Silvio Sosa Mark Poli Aurelia Tubaro Orfeo Sbaizero Paola Lorenzon 《Toxicology letters》2014
Palytoxins (PLTXs) are known seafood contaminants and their entrance into the food chain raises concern about possible effects on human health. The increasing number of analogs being identified in edible marine organisms complicates the estimation of the real hazard associated with the presence of PLTX-like compounds. So far, 42-OH-PLTX is one of the few congeners available, and the study of its toxicity represents an important step toward a better comprehension of the mechanism of action of this family of compounds. From this perspective, the aim of this work was to investigate the in vivo and in vitro effect of 42-OH-PLTX on skeletal muscle, one of the most sensitive targets for PLTXs. Our results demonstrate that 42-OH-PLTX causes damage at the skeletal muscle level with a cytotoxic potency similar to that of PLTX. 42-OH-PLTX induces cytotoxicity and cell swelling in a Na+-dependent manner similar to the parent compound. However, the limited Ca2+-dependence of the toxic insult induced by 42-OH-PLTX suggests a specific mechanism of action for this analog. Our results also suggest an impaired response to the physiological agonist acetylcholine and altered cell elasticity. 相似文献
64.
A new methodological approach to adjust alcohol exposure distributions to improve the estimation of alcohol‐attributable fractions 下载免费PDF全文
65.
Recently, one of the world’s leading scientific and technical advisory groups, the U.S. President’s Council of Advisors on Science and Technology (or PCAST), published an assessment of the research supporting several forensic science procedures in regular use. PCAST was particularly interested in pattern recognition or comparison procedures, specifically: simple and mixed DNA profiles; bite marks; latent fingerprints; firearms; footwear; and hair analysis. In its report and recommendations PCAST emphasised the primacy of validation. In response, the Council of the Australian and New Zealand Forensic Science Society produced a short statement suggesting that the PCAST report has limited application to forensic science in Australia and New Zealand. This short commentary offers an alternative perspective. 相似文献
66.
目的针对目前医院病床基本无配备床头抬高角度测量工具的现状,调查护士目测法评估床头抬高角度的测量误差,探讨使用精确测量工具的必要性。方法随机选择我院各护理单元主管护师、护师和护士各2名,共96名。采用目测法评估床头抬高15°、30°、45°三种角度,与角度尺精确测量法比较床头抬高角度的差异。结果目测评估床头抬高15°、30°、45°所产生的实际角度分别为(10.56±3.67)°、(19.54±6.58)°、(38.18±9.69)°,测量误差发生率96.2%,其中实际测量角度小于目标角度,占93.8%,实际测量角度大于目标角度,占2.4%,与角度尺测量方法比较,差异有统计学意义(P〈0.01)。结论目测法评估会影响有特殊卧位要求患者的治疗效果,并发症发生几率增加,应使用精确的测量工具。 相似文献
67.
We present a case of a man with an ischemic lesion of the left hippocampus. Detailed neuropsychological assessment revealed susceptibility to retroactive interference and a tendency to make intrusion errors in addition to mild deficits in the verbal memory processes. Although retroactive interference and intrusion errors are normally considered to be the manifestations of frontal lobe dysfunctions, the idea of susceptibility to interference has recently begun to emerge in the literature, as an explanation of medial temporal lobe amnesia. Our data support this new theory, suggesting that one role of the hippocampus is to decrease the interference during the learning processes. 相似文献
68.
Ravil Sharifulin Alexander Bogachev-Prokophiev Sergey Zheleznev Igor Demin Alexey Pivkin Alexander Afanasyev Alexander Karaskov 《The Journal of thoracic and cardiovascular surgery》2019,157(1):134-141.e3
Objective
Although the Ross procedure provides excellent long-term survival and a high quality of life, its use has been limited to relatively few centers. In this study, we evaluated long-term Ross procedure results in adults to assess the predictors of pulmonary autograft durability.Methods
Between 1998 and 2015, 793 consecutive adult patients underwent the Ross procedure. The total root replacement technique was used in all patients.Results
The early mortality rate was 2.9%. The mean follow-up duration was 6.5 ± 3.2 years, and the 10-year survival rate was 90.4%. Longitudinal mixed-effects ordinal regression identified a combination of bicuspid aortic valve and aortic insufficiency (odds ratio, 2.19; P < .001) as predictors for progression of autograft valve insufficiency at follow-up. The cumulative incidence of autograft reoperations at 10 years was 8.6%. Competing risk regression identified bicuspid aortic valve insufficiency as the independent predictor of autograft reoperation (subdistribution hazard ratio, 2.16; P = .030). Moreover, patients with bicuspid aortic valve and aortic insufficiency had greater increases in annulus (P < .001), sinus (P < .001), and ascending aorta (P < .001) diameters over time.Conclusions
For patients undergoing the Ross procedure, a combination of bicuspid aortic valves and aortic insufficiency is the main risk factor for late autograft dilatation and dysfunction. 相似文献69.
AbstractThere is increasing interest in Bayesian group sequential design because of its potential to improve efficiency in clinical trials, to shorten drug development time, and to enhance statistical inference precision without undermining the clinical trial’s integrity or validity. We propose a Bayesian sequential design for clinical trials with time-to-event outcomes and use alpha spending functions to control the overall Type I error rate. Bayes factor is adapted for decision-making at interim analyses. Algorithms are presented to make decision rules and to calculate power of the proposed tests. Sensitivity analysis is implemented to evaluate the impact of different choices of prior parameters on choosing critical values. The power of tests, the expected event size of the proposed design, and the quality of estimators are studied through simulations, and compared with the frequentist group sequential design. Simulations show that at fixed total number of events, the proposed design can achieve greater power and require smaller expected event size when appropriate priors are chosen, compared with the frequentist group sequential design. The feasibility of the proposed design is further illustrated on a real dataset. Supplementary materials for this article are available online. 相似文献
70.
《Clinical neurophysiology》2021,132(10):2431-2439
ObjectiveThe purpose of this investigation was to better understand the effects of concussions on the ability to selectively up or down-regulate incoming somatosensory information based on relevance.MethodsMedian nerve somatosensory-evoked potentials (SEPs) were elicited from electrical stimulation and recorded from scalp electrodes while participants completed tasks that altered the relevance of specific somatosensory information being conveyed along the stimulated nerve.ResultsWithin the control group, SEP amplitudes for task-relevant somatosensory information were significantly greater than for non-relevant somatosensory information at the earliest cortical processing potentials (N20-P27). Alternatively, the concussion history group showed similar SEP amplitudes for all conditions at early processing potentials, however a pattern similar to controls emerged later in the processing stream (P100) where both movement-related gating and facilitation of task-relevant information were present.ConclusionsPreviously concussed participants demonstrated impairments in the ability to up-regulate relevant somatosensory information at early processing stages. These effects appear to be chronic, as this pattern was observed on average several years after participants’ most recent concussion.SignificanceGiven the role of the prefrontal cortex in relevancy-based facilitation during movement-related gating, these findings lend support to the notion that this brain area may be particularly vulnerable to concussive forces. 相似文献