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1.
Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
2.

Background

European guidelines recommend targeted temperature management (TTM) in post-cardiac arrest care. A large multicentre clinical trial, however, showed no difference in mortality and neurological outcome when comparing hypothermia to normothermia with early treatment of fever. The study results were valid given a strict protocol for the assessment of prognosis using defined neurological examinations. With the current range of recommended TTM temperatures, and applicable neurological examinations, procedures may differ between hospitals and the variation of clinical practice in Sweden is not known.

Aim

The aim of this study was to investigate current practice in post-resuscitation care after cardiac arrest as to temperature targets and assessment of neurological prognosis in Swedish intensive care units (ICUs).

Methods

A structured survey was conducted by telephone or e-mail in all Levels 2 and 3 (= 53) Swedish ICUs during the spring of 2022 with a secondary survey in April 2023.

Results

Five units were not providing post-cardiac arrest care and were excluded. The response rate was 43/48 (90%) of the eligible units. Among the responding ICUs, normothermia (36–37.7°C) was applied in all centres (2023). There was a detailed routine for the assessment of neurological prognosis in 38/43 (88%) ICUs. Neurological assessment was applied 72–96 h after return of spontaneous circulation in 32/38 (84%) units. Electroencephalogram and computed tomography and/or magnetic resonance imaging were the most common technical methods available.

Conclusion

Swedish ICUs use normothermia including early treatment of fever in post-resuscitation care after cardiac arrest and almost all apply a detailed routine for the assessment of neurological prognosis. However, available methods for prognostic evaluation varies between hospitals.  相似文献   
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目的探讨神经节苷脂联合苯巴比妥治疗新生儿缺氧缺血性脑病的临床疗效及对新生儿神经功能的影响。方法选取2017年3月-2019年3月本院收治的缺氧缺血性脑病新生儿106例,随机分为两组,对照组应用苯巴比妥治疗,研究组应用神经节苷脂联合苯巴比妥治疗。比较临床治疗有效率、神经功能恢复效果、治疗前后NBNA评分统计。结果研究组临床治疗有效率、不同程度的时间恢复效果、治疗后NBNA评分均高于对照组(P<0.05)。结论治疗新生儿缺氧缺血性脑病治疗过程当中,神经节苷脂联合苯巴比妥的治疗效果理想,可改善新生儿神经功能。  相似文献   
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目的探讨芪蛭活血通络饮治疗老年急性脑梗死气虚血瘀证患者临床疗效,观察其对患者炎性指标、纤维化指标、神经功能恢复的影响。方法采用随机数字表法将94例患者分为观察组和对照组各47例。对照组采用西医常规治疗,观察组在对照组基础上予芪蛭活血通络饮,每日1剂,每次150 mL,每日2次,口服(吞咽困难者胃管给药),2组均连续治疗2周。观察2组治疗前后血液流变学指标、转化生长因子-β1(TGF-β1)、同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CPR)、血管内皮生长因子(VEGF)水平,及神经功能(NIHSS)评分、日常生活能力(ADL)评分,比较2组临床疗效及不良反应。结果与本组治疗前比较,2组治疗后全血高切黏度、全血低切黏度、纤维蛋白原、hs-CPR、Hcy水平明显下降,TGF-β1、VEGF水平明显升高(P<0.05);2组治疗后比较,观察组上述实验室指标改善明显优于对照组(P<0.05)。与本组治疗前比较,2组治疗后NIHSS评分明显降低,ADL评分明显升高(P<0.05);2组治疗后比较,观察组NIHSS评分低于对照组,ADL评分高于对照组(P<0.05)。观察组总有效率为93.62%(44/47),对照组为74.47%(35/47),2组比较差异有统计学意义(P<0.05)。观察组不良反应率为14.89%(7/47),对照组为19.15%(9/47),2组比较差异无统计学意义(P>0.05)。结论芪蛭活血通络饮联合西医常规疗法治疗老年急性脑梗死气虚血瘀证疗效满意,可有效减轻患者炎症反应,改善机体高凝状态,促进神经功能修复。  相似文献   
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IntroductionA three-level model of interoception has recently been defined. We aim to study the interoceptive processing in individuals with functional motor disorder (FMD).MethodsTwenty-two patients with FMD were compared to 23 healthy controls. They underwent a protocol measuring different levels of interoception including: accuracy (a heart-beat tracking task), awareness (participant's confidence level) and sensibility (the Body Awareness Questionnaire-BAQ). Depression, anxiety and alexithymia were assessed by means of validated clinical scales.ResultsThe FMD group showed a lower cardiac interoceptive accuracy and sensibility than healthy controls but they did not differ in terms of awareness (p = 0.03 and 0.005 respectively). They were aware of their poor performance in the accuracy task. Cardiac interoceptive accuracy positively correlated with the BAQ sub-scales “Predict Body Reaction” (r = 0.49, p = 0.001) and “Sleep-Wake Cycle” (r = 0.52, p < 0.001). A mediation analysis showed a significant indirect effect of group on cardiac interoceptive accuracy through BAQ “Predict Body Reaction” (b = −2.95, 95% BCa CI[-7.2;-0.2]). The direct effect of group on “Predict Body Reaction” was still significant (b = − 6.95, p = 0.02, 95% CI[-13.18;-0.73]).ConclusionsPeople with FMD have impaired cardiac interoceptive accuracy and sensibility but no difference in metacognitive interoception compared to healthy controls.  相似文献   
9.
Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase(PI3 K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3 K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting(GV24) and Baihui(GV20) acupoints, with a dilatational wave(1–20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3 K/Akt signaling pathwayrelated factors Beclin-1, mammalian target of rapamycin(mTOR), and PI3 K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3 K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting(GV24) and Baihui(GV20) acupoints activated the PI3 K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China(approval No. 8150150901) on March 10, 2016.  相似文献   
10.
AimSystemic lupus erythematosus (SLE) is an unusual risk factor for cerebral venous sinus thrombosis (CVST). As few CVST patients with SLE have been reported, little is known regarding its frequency as an underlying etiology, clinical characteristics, or long-term outcome. We evaluated a large cohort of CVST patients with SLE in a multicenter study of cerebral venous thrombosis, the VENOST study, and their clinical characteristics.Material and MethodAmong the 1144 CVST patients in the VENOST cohort, patients diagnosed with SLE were studied. Their demographic and clinical characteristics, etiological risk factors, venous involvement status, and outcomes were recorded.ResultsIn total, 15 (1.31%) of 1144 CVST patients had SLE. The mean age of these patients was 39.9 ± 12.1 years and 13 (86.7%) were female. Presenting symptoms included headache (73.3%), visual field defects (40.0%), and altered consciousness (26.7%). The main sinuses involved were the transverse (60.0%), sagittal (40.0%), and sigmoid (20.0%) sinuses. Parenchymal involvement was not seen in 73.3% of the patients. On the modified Rankin scale, 92.9% of the patients scored 0-1 at the 1-month follow-up and 90.9% scored 0-1 at the 1-year follow-up.ConclusionsSLE was found in 1.31% of the CVST patients, most frequently in young women. Headache was the most common symptom and the CVST onset was chronic in the majority of cases. The patient outcomes were favorable. CVST should be suspected in SLE patients, even in those with isolated chronic headache symptoms with or without other neurological findings.  相似文献   
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