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BackgroundThe reduction of shoulder dislocation requires adequate procedural sedation and analgesia. The mixture of midazolam and fentanyl is reported in the literature, but long-acting benzodiazepines in conjunction with fentanyl are lacking.Study ObjectiveOur aim was to compar e IV diazepam with IV midazolam in moderate procedural sedation (based on the classification of the American Society of Anesthesiologists) for the reduction of shoulder dislocation.MethodsThis was a randomized controlled clinical trial conducted from April 2019 to December 2019 in the emergency department of a university-affiliated hospital in Tehran, Iran. Participants were adult patients (aged 18–65 years) with anterior shoulder dislocation. Group A (n = 42) received diazepam 0.1 mg/kg plus fentanyl 1 μg/kg IV and group B received midazolam 0.1 mg/kg plus fentanyl 1 μg g/kg IV. Main outcomes measured were onset of muscle relaxation, time taken to reduction, total procedure time, number of the reduction attempts, patient recovery time, the occurrence of the adverse effects, amount of the pain reported by the patients using visual analog scale, and patients and physicians overall satisfaction with the procedure using a Likert scale question.ResultsEighty-one patients were included. The mean ± standard deviation time of the onset of the muscle relaxation and time taken to reduction was shorter in the diazepam plus fentanyl group (p = 0.016 and p = 0.001, respectively). Adverse effects and pain relief were not statistically different between the two groups. Patient recovery time and total procedure time was shorter in the midazolam plus fentanyl group (p = 0.008 and p = 0.02, respectively). The overall satisfaction of patients and physicians was higher in the diazepam plus fentanyl group.ConclusionsAs compared with midazolam plus fentanyl, diazepam plus fentanyl was superior in terms of the onset of the muscle relaxation, patient and physician satisfaction, and time taken to reduction.  相似文献   
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The aim of this study was to develop nanofibrous silk substrates for limbal stem cell expansion that can serve as a potential alternative substrate to replace human amniotic membrane. The human limbal stem cell was used to evaluate the biocompatibility of substrates (random and oriented nanofibrous mats, and human amniotic membrane) based on their phenotypic profile, viability, proliferation, and attachment ability. Biocompatibility results indicated that all substrates were highly biocompatible, as limbal stem cells could favorably attach and proliferate on the nanofibrous surfaces. Microscopic figures showed that the human limbal stem cells were firmly anchored to the substrates and were able to retain a normal corneal stem cell phenotype. Microscopic analyses illustrated that cells infiltrated the nanofibers and successfully formed a three-dimensional corneal epithelium, which was viable for 15 days. Immunocytochemistry and real-time PCR results revealed no change in the expression profile of limbal stem cells grown on nanofibrous substrates when compared to those grown on human amniotic membrane. In addition, electrospun nanofibrous silk substrates especially oriented mat provides not only a milieu supporting limbal stem cells expansion, but also serve as a useful alternative carrier for ocular surface tissue engineering and could be used as an alternative substrate to amniotic membrane.  相似文献   
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Purpose

Functional magnetic resonance imaging (fMRI) in resting state can be used to evaluate the functional organization of the human brain in the absence of any task or stimulus. The functional connectivity (FC) has non-stationary nature and consented to be varying over time. By considering the dynamic characteristics of the FC and using graph theoretical analysis and a machine learning approach, we aim to identify the laterality in cases of temporal lobe epilepsy (TLE).

Methods

Six global graph measures are extracted from static and dynamic functional connectivity matrices using fMRI data of 35 unilateral TLE subjects. Alterations in the time trend of the graph measures are quantified. The random forest (RF) method is used for the determination of feature importance and selection of dynamic graph features including mean, variance, skewness, kurtosis, and Shannon entropy. The selected features are used in the support vector machine (SVM) classifier to identify the left and right epileptogenic sides in patients with TLE.

Results

Our results for the performance of SVM demonstrate that the utility of dynamic features improves the classification outcome in terms of accuracy (88.5% for dynamic features compared with 82% for static features). Selecting the best dynamic features also elevates the accuracy to 91.5%.

Conclusion

Accounting for the non-stationary characteristics of functional connectivity, dynamic connectivity analysis of graph measures along with machine learning approach can identify the temporal trend of some specific network features. These network features may be used as potential imaging markers in determining the epileptogenic hemisphere in patients with TLE.

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Applications in imaging and spectroscopy rely on pulse processing methods for appropriate data generation. Often, the particular method utilized does not highly impact data quality, whereas in some scenarios, such as in the presence of high count rates or high frequency pulses, this issue merits extra consideration. In the present study, a new approach for pulse processing in nuclear medicine imaging and spectroscopy is introduced and evaluated. The new non-linear recursive filter (NLRF) performs nonlinear processing of the input signal and extracts the main pulse characteristics, having the powerful ability to recover pulses that would ordinarily result in pulse pile-up. The filter design defines sampling frequencies lower than the Nyquist frequency.In the literature, for systems involving NaI(Tl) detectors and photomultiplier tubes (PMTs), with a signal bandwidth considered as 15 MHz, the sampling frequency should be at least 30 MHz (the Nyquist rate), whereas in the present work, a sampling rate of 3.3 MHz was shown to yield very promising results. This was obtained by exploiting the known shape feature instead of utilizing a general sampling algorithm. The simulation and experimental results show that the proposed filter enhances count rates in spectroscopy. With this filter, the system behaves almost identically as a general pulse detection system with a dead time considerably reduced to the new sampling time (300 ns). Furthermore, because of its unique feature for determining exact event times, the method could prove very useful in time-of-flight PET imaging.  相似文献   
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