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91.
Dennis J. Rebergen Sunil B. Nagaraj Eric S. Rosenthal Matt T. Bianchi Michel J. A. M. van Putten M. Brandon Westover 《Journal of clinical monitoring and computing》2018,32(1):53-61
We developed a simple and fully automated method for detecting artifacts in the R-R interval (RRI) time series of the ECG that is tailored to the intensive care unit (ICU) setting. From ECG recordings of 50 adult ICU-subjects we selected 60 epochs with valid R-peak detections and 60 epochs containing artifacts leading to missed or false positive R-peak detections. Next, we calculated the absolute value of the difference between two adjacent RRIs (adRRI), and obtained the empirical probability distributions of adRRI values for valid R-peaks and artifacts. From these, we calculated an optimal threshold for separating adRRI values arising from artifact versus non-artefactual data. We compared the performance of our method with the methods of Berntson and Clifford on the same data. We identified 257,458 R-peak detections, of which 235,644 (91.5%) were true detections and 21,814 (8.5%) arose from artifacts. Our method showed superior performance for detecting artifacts with sensitivity 100%, specificity 99%, precision 99%, positive likelihood ratio of 100 and negative likelihood ratio <0.001 compared to Berntson’s and Clifford’s method with a sensitivity, specificity, precision and positive and negative likelihood ratio of 99%, 78%, 82%, 4.5, 0.013 for Berntson’s method and 55%, 98%, 96%, 27.5, 0.460 for Clifford’s method, respectively. A novel algorithm using a patient-independent threshold derived from the distribution of adRRI values in ICU ECG data identifies artifacts accurately, and outperforms two other methods in common use. Furthermore, the threshold was calculated based on real data from critically ill patients and the algorithm is easy to implement. 相似文献
92.
93.
Jon J. Ford Matt C. Richards Luke D. Surkitt Alexander Y.P. Chan Sarah L. Slater Nicholas F. Taylor Andrew J. Hahne 《Archives of physical medicine and rehabilitation》2018,99(12):2504-2512.e12
Objective
To identify predictors for back pain, leg pain, and activity limitation in patients with early persistent low back disorders (LBDs).Design
Prospective inception cohort study.Setting
Primary care private physiotherapy clinics in Melbourne, Australia.Participants
Individuals (N=300) aged 18-65 years with low back and/or referred leg pain of ≥6 weeks and ≤6 months duration.Interventions
Not applicable.Main Outcome Measures
Numeric rating scales for back pain and leg pain as well as the Oswestry Disability Scale.Results
Prognostic factors included sociodemographics, treatment related factors, subjective/physical examination, subgrouping factors, and standardized questionnaires. Univariate analysis followed by generalized estimating equations were used to develop a multivariate prognostic model for back pain, leg pain, and activity limitation. Fifty-eight prognostic factors progressed to the multivariate stage where 15 showed significant (P<.05) associations with at least 1 of the 3 outcomes. There were 5 indicators of positive outcome (2 types of LBD subgroups, paresthesia below waist, walking as an easing factor, and low transversus abdominis tone) and 10 indicators of negative outcome (both parents born overseas, deep leg symptoms, longer sick leave duration, high multifidus tone, clinically determined inflammation, higher back and leg pain severity, lower lifting capacity, lower work capacity, and higher pain drawing percentage coverage). The preliminary model identifying predictors of LBDs explained up to 37% of the variance in outcome.Conclusions
This study evaluated a comprehensive range of prognostic factors reflective of both the biomedical and psychosocial domains of LBDs. The preliminary multivariate model requires further validation before being considered for clinical use. 相似文献94.
95.
The Tougher the Better: An Economic Analysis of Increased Payment Thresholds on the Performance of General Practices
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We investigate whether and how a change in performance‐related payment motivated General Practitioners (GPs) in Scotland. We evaluate the effect of increases in the performance thresholds required for maximum payment under the Quality and Outcomes Framework in April 2006. A difference‐in‐differences estimator with fixed effects was employed to examine the number of patients treated under clinical indicators whose payment schedules were revised and to compare these with the figures for those indicators whose schedules remained unchanged. The results suggest that the increase in the maximum performance thresholds increased GPs' performance by 1.77% on average. Low‐performing GPs improved significantly more (13.22%) than their high‐performing counterparts (0.24%). Changes to maximum performance thresholds are differentially effective in incentivising GPs and could be used further to raise GPs' performance across all indicators. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
96.
Synthesis of two potent glucocorticoid receptor agonists labeled with carbon‐14 and stable isotopes
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Bachir Latli Jonathan T. Reeves Zhulin Tan Matt Hrapchak Jinhua J. Song Carl B. Busacca Chris H. Senanayake 《Journal of labelled compounds & radiopharmaceuticals》2015,58(11-12):445-452
Two potent glucocorticoid receptor agonists were prepared labeled with carbon‐14 and with stable isotopes to perform drug metabolism, pharmacokinetics, and bioanalytical studies. Carbon‐14 labeled (1) was obtained from an enantiopure alkyne (5) via a Sonogashira coupling to a previously reported 5‐amino‐4‐iodo‐[2‐14C]pyrimidine [14C]‐(6), followed by a base‐mediated cyclization (1) in 72% overall radiochemical yield. Carbon‐14 labeled (2) was prepared in five steps employing a key benzoic acid intermediate [14C]‐(13), which was synthesized in one pot from enolization of trifluoromethylketone (12), followed by bromine–magnesium exchange and then electrophile trapping reaction with [14C]‐carbon dioxide. A chiral auxiliary (S)‐1‐(4‐methoxyphenyl)ethylamine was then coupled to this acid to give [14C]‐(15). Propargylation and separation of diastereoisomers by crystallizations gave the desired diastereomer [14C]‐(17) in 34% yield. Sonogashira coupling to iodopyridine (10) followed by cyclization to the azaindole [14C]‐(18) and finally removal of the chiral auxiliary gave [14C]‐(2) in 7% overall yield. For stable isotope syntheses, [13C6]‐(1) was obtained in three steps using [13C4]‐(6) and trimethylsilylacetylene‐[13C2] in 26% yield, while [2H5]‐(2) was obtained by first preparing the iodopyridine [2H5]‐(10) in five steps. Then, Sonogashira coupling to chiral alkyne (24) and cyclization gave [2H5]‐(2) in 42% overall yield. 相似文献
97.
Fear expression is mediated by an activation of the centromedial amygdala (CEm), the major output nucleus of the amygdaloid complex. Consistently, fear extinction is associated with an increased synaptic inhibition as well as a suppression of the excitability of the CEm neurons. However, little is known about the role of CEm glutamatergic synapses in fear regulation and anxiety-like behaviors. The BDNF Val66Met, a single-nucleotide polymorphism in the human BDNF gene, impairs fear extinction and leads to anxiety-like symptoms. To determine whether the BDNF Val66Met polymorphism affects the CEm excitatory synapses, we examined basal glutamatergic synaptic transmission and plasticity in the CEm neurons of BDNF Val66Met knock-in (BDNFMet/Met) mice. The BDNF Val66Met single-nucleotide polymorphism exerted an opposite effect on non-NMDA and NMDA receptor transmission with a potentiation of the former and a suppression of the latter. In addition, the decay time of NMDA currents was decreased in BDNFMet/Met mice, suggesting a modification of NMDA receptor subunit composition. Unlike the wild-type mice that exhibited a potentiation of non-NMDA receptor transmission following fear conditioning and a depotentiation upon fear extinction, BDNFMet/Met mice failed to show this experience-dependent synaptic plasticity in the CEm neurons. Our results suggest that the elevated non-NMDA receptor transmission, the suppression of NMDA receptor transmission, and an impairment of synaptic plasticity in the CEm neurons might contribute to the fear extinction deficit and increased anxiety-like symptoms in BDNF Val66Met carriers. 相似文献
98.
Thomas Mason William Whittaker Andrew Jones Matt Sutton 《Addiction (Abingdon, England)》2021,116(11):3082-3093
99.
100.
Mutchler Matt G. Wagner Glenn J. McDavitt Bryce Woldetsadik Mahlet A. Kegeles Susan M. El-Khoury Cynthia Nogg Kelsey A. Klinger Ian A. Mokhbat Jacques Ballan Elie G. 《AIDS and behavior》2022,26(9):3089-3098
AIDS and Behavior - We are not aware of any validated sexual health communication scales for use with young men who have sex with men (YMSM). We used data from an HIV prevention study in Lebanon... 相似文献