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31.
ObjectivesTo assess the impact of the COVID-19 pandemic on clinical research and the use of electronic approaches to mitigate this impact.MethodsWe compared the utilization of electronic consenting, remote visits, and remote monitoring by study monitors in all research studies conducted at Mayo Clinic sites (Arizona, Florida, and Minnesota) before and during the COVID-19 pandemic (ie, between May 1, 2019 and December 31, 2020). Participants are consented through a participant-tracking system linked to the electronic health record.ResultsBetween May 2019, and December 2020, there were 130,800 new consents across every modality (electronic and paper) to participate in a non-trial (107,176 [82%]) or a clinical trial (23,624 [18%]). New consents declined from 5741 in February 2020 to 913 in April 2020 but increased to 11,864 in November 2020. The mean (standard deviation [SD]) proportion of electronic consent increased from 22 (2%) before to 45 (20%) during the pandemic (P=.001). Mean (SD) remote electronic consenting increased from 0.3 (0.5%) to 29 (21%) (P<.001). The mean (SD) number of patients with virtual visits increased from 3.5 (2.4%) to 172 (135%) (P=.003) per month between pre-COVID (July 2019 to February 2020) and post-COVID (March to December 2020) periods. Virtual visits used telemedicine (68%) or video (32%). Requests for remote monitor access to complete visits increased from 44 (17%) per month between May 2019 and February 2020 to 111 (74%) per month between March and December 2020 (P=.10).ConclusionAfter a sharp early decline, the enrollment of new participants and ongoing study visits recovered during the COVID-19 pandemic. This recovery was accompanied by the increased use of electronic tools.  相似文献   
32.
目的:探讨E-Tracking技术在评价妊娠期高血压疾病患者颈动脉弹性功能中的应用价值。方法:对29例妊娠晚期妊娠期高血压疾病患者(疾病组)和32例正常妊娠晚期妇女(对照组)进行双侧颈总动脉血管弹性指标(弹性模量Ep、僵硬度β、顺应性AC、脉搏波传导速度PWVβ及膨大指数AI)及内中膜厚度(IMT)的测量,并进行统计学分析。结果:疾病组双侧颈总动脉Ep、β、PWVβ及AI较对照组升高,疾病组AC较对照组减低,具有极显著性差异(P〈0.01);两组间颈总动脉内中膜厚度无显著性差异(P〉0.05)。结论:血管回声跟踪技术在评价妊娠期高血压疾病血管弹性方面具有一定价值。  相似文献   
33.
吴振卿 《中国当代医药》2012,19(20):125-126
目的对左心房容积追踪技术评价高血压患者左心房功能变化中的价值进行分析。方法采用多普勒超声诊断仪.频率为1~5MHz,嘱患者左侧卧位,测心电图,记录静息心率,患者设为实验组。结果通过实验组和对照组之间进行对比发现,左心房容积追踪技术在评价高血压患者左心房功能改变中有重大临床意义。结论左心房容积追踪技术作为一种新的评价左房功能技术,可通过自动追踪左心房壁内膜运动轨迹获得实时左房容积曲线,快捷、全面评价左房功能改变。应用左房容积追踪技术可探讨不同厚度左室壁高血压患者的左心房功能差异。  相似文献   
34.
The advent of automated locomotor activity methodologies has been extremely useful in removing the subjectivity and bias out of measuring this parameter in rodents. However, many of these behavioural studies are still conducted in novel environments, rather than in ones that the animals are familiar with, such as their home cage. The purpose of the present series of experiments was to develop an automated home cage tracking (HCT) profile using EthoVision software and assessing the acute effects of stimulant (amphetamine and methamphetamine, 0-5 mg/kg, sc) and sedative (diazepam, 0-20 mg/kg, sc and chlordiazepoxide, 0-50 mg/kg sc) drugs in this apparatus. Young adult male Sprague-Dawley rats were used, and the home cage locomotor activity was recorded for 11-60 min following administration (n=4 per group). For amphetamine and methamphetamine, a dose-dependent increase in home cage activity was evident for both drugs, with a plateau, followed by reduction at higher doses. Methamphetamine was more potent, whereas amphetamine produced greater maximal responses. Both diazepam and chlordiazepoxide dose-dependently reduced locomotor activity, with diazepam exhibiting a greater potency and having stronger sedative effects than chlordiazepoxide. Three doses of each drug were selected at the 31-40 min time period following administration, and compared to open field responses. Diazepam, chlordiazepoxide and amphetamine did not produce significant changes in the open field, whilst methamphetamine produced a significant increase in the 2.5 mg/kg group. In conclusion, these studies have successfully developed a sensitive HCT methodology that has been validated using drugs with stimulant and sedative properties in the same test conditions, with relatively small numbers of animals required to produce statistically significant results. It has proven superior to the open field investigations in allowing dose-response effects to be observed over a relatively short observation period (i.e. 10 min) for both stimulants and sedatives. In addition, the HCT system can determine differences in potency and efficacy between drugs of a similar chemical class.  相似文献   
35.
Acute exercise has been shown to exhibit different effects on human sensorimotor behavior; however, the causes and mechanisms of the responses are often not clear. The primary aim of the present study was to determine the effects of incremental running until exhaustion on sensorimotor performance and adaptation in a tracking task. Subjects were randomly assigned to a running group (RG), a tracking group (TG), or a running followed by tracking group (RTG), with 10 subjects assigned to each group. Treadmill running velocity was initially set at 2.0 m s(-1), increasing by 0.5 m s(-1) every 5 min until exhaustion. Tracking consisted of 35 episodes (each 40 s) where the subjects' task was to track a visual target on a computer screen while the visual feedback was veridical (performance) or left-right reversed (adaptation). Resting electroencephalographic (EEG) activity was recorded before and after each experimental condition (running, tracking, rest). Tracking performance and the final amount of adaptation did not differ between groups. However, task adaptation was significantly faster in RTG compared to TG. In addition, increased alpha and beta power were observed following tracking in TG but not RTG although exhaustive running failed to induce significant changes in these frequency bands. Our results suggest that exhaustive running can facilitate adaptation processes in a manual tracking task. Attenuated cortical activation following tracking in the exercise condition was interpreted to indicate cortical efficiency and exercise-induced facilitation of selective central processes during actual task demands.  相似文献   
36.
The simple spike firing of cerebellar Purkinje cells encodes information on the kinematics of limb movements. However, these conclusions have been primarily based on averaging the discharge of Purkinje cells across trials and time and there is little information on whether Purkinje cell simple spike firing encodes specific motor errors during limb movements. Therefore, this study investigated single-trial correlations between the instantaneous simple spike firing of Purkinje cells with various kinematics and error signals. Purkinje cells (n = 126) were recorded in the intermediate and lateral zones centered on the primary fissure while three monkeys intercepted and tracked a target moving in a circle. Cross-correlation analysis was performed between the instantaneous simple spike firing rate and speed, the directional component of the velocity vector, and error signals during single movement trials. Significant correlations at physiologically relevant lags of ±250 ms were observed with tracking speed for 37% of Purkinje cells, with the velocity component in 39%, with direction error in 6% and speed error in 25%. Simple spike firing of the majority of Purkinje cells with significant correlation showed a negative lag with respect to speed and a positive lag with respect to error signals. We hypothesize that the cerebellum is involved in movement planning and control by continuously monitoring movement errors and making intermittent corrections that are represented as fluctuations in the speed profile.  相似文献   
37.
Modern neuroscience and the interest in biomimetic control design demand increasingly sophisticated experimental techniques that can be applied in freely moving animals under realistic behavioral conditions. To explore sensorimotor flight control mechanisms in free-flying fruit flies (Drosophila melanogaster), we equipped a wind tunnel with a Virtual Reality (VR) display system based on standard digital hardware and a 3D path tracking system. We demonstrate the experimental power of this approach by example of a ‘one-parameter open loop’ testing paradigm. It provided (1) a straightforward measure of transient responses in presence of open loop visual stimulation; (2) high data throughput and standardized measurement conditions from process automation; and (3) simplified data analysis due to well-defined testing conditions.

Being based on standard hardware and software techniques, our methods provide an affordable, easy to replicate and general solution for a broad range of behavioral applications in freely moving animals. Particular relevance for advanced behavioral research tools originates from the need to perform detailed behavioral analyses in genetically modified organisms and animal models for disease research.  相似文献   

38.
We are working to develop beating-heart atrial septal defect (ASD) closure techniques using real-time 3D ultrasound guidance. The major image processing challenges are the low-image quality and the processing of information at high-frame rate. This paper presents comparative results for ASD tracking in time sequences of 3D volumes of cardiac ultrasound. We introduce a block flow technique, which combines the velocity computation from optical flow for an entire block with template matching. Enforcing adapted similarity constraints to both the previous and first frames ensures optimal and unique solutions. We compare the performance of the proposed algorithm with that of block matching and region-based optical flow on eight in vivo 4D datasets acquired from porcine beating-heart procedures. Results show that our technique is more stable and has higher sensitivity than both optical flow and block matching in tracking ASDs. Computing velocity at the block level, our technique tracks ASD motion at 2 frames/s, much faster than optical flow and comparable in computation cost to block matching, and shows promise for real-time (30 frames/s). We report consistent results on clinical intra-operative images and retrieve the cardiac cycle (in ungated images) from error analysis. Quantitative results are evaluated on synthetic data with maximum tracking errors of 1 voxel.  相似文献   
39.
BackgroundState dental boards maintain minimal demographic and practice characteristics about licensed dentists. The authors describe the creation and monitoring of an enhanced surveillance system concerning Iowa's dentists.MethodsThe Iowa Dentist Tracking System (IDTS) was used to collect demographic, educational, practice arrangement, office location and work hour data for all active Iowa dentists beginning in 1997. IDTS staff members add newly licensed dentists to the system as practice locations become available. They also contact each dental office semiannually by telephone to update this information. The IDTS Advisory Committee meets annually to review these data and monitor trends.ResultsThe Iowa dentist workforce was relatively stable from 1997 through 2007; however, a large number of dentists are expected to retire during the next decade, which could create a shortage of providers, especially in rural areas. Although the percentage of male and female dentists who practice part time (< 32 hours per week) decreased between 1997 and 2007, young female dentists are more likely than young male dentists to practice part time.ConclusionsIDTS is a workforce tracking model that can be used to understand trends at the community, regional and state levels. An aging dentist workforce in Iowa could put a strain on the public's ability to access dental care, especially in rural counties.Practice ImplicationsIn the development of workforce policy, workforce tracking systems such as IDTS provide additional information in considering the number of dentists, location, accessibility and potential productivity of a workforce.  相似文献   
40.
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