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Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.  相似文献   
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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   
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目的探讨前列腺原发胃肠道外间质瘤诊治要点。 方法回顾性分析我院2017年9月诊治的1例高危原发性前列腺胃肠道外间质瘤临床病理特征资料、随访情况,总结现有文献讨论总结本病诊治心得。 结果65岁男性,因"前列腺电切术后2年,反复血尿3个月余"入院。术前MRI考虑为来源不清的盆腔巨大实性占位(115 mm×105 mm×85 mm),经直肠穿刺诊断为梭形细胞来源的肿瘤。行盆腔肿瘤切除+膀胱前列腺腺切除+盆腔淋巴结清扫术+Bricker术。术后病理提示为前列腺原发胃肠道外间质瘤[CD117(+);Dog1(+);CD34(+);PSA(+);AR(+);P504s(+);Ki-67(2%)]。术后肿瘤组织全外显子测序提示为C-Kit基因(Exon 11 p.Q556-V560del)存在明显临床意义突变,筛选靶向药物甲磺酸伊马替尼+比卡鲁胺(PSA平稳后停用)口服,术后随访18个月无肿瘤复发及不良并发症。 结论前列腺原发胃肠道外间质瘤罕见,需与前列腺其他良恶性肿瘤相鉴别诊断。全外显子测序了解其发病高危基因,同时筛选药物辅助治疗可使患者生存获益。  相似文献   
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Introduction: Cancer, in particular breast cancer, is one of the leading causes of death among women. Good nutritional status contributes to the efficacy of treatment and recovery, and nutritional interventions can minimize the adverse effects of cancer therapy.

Aim: The aim of this study was to describe the potential role of dietary counseling in breast cancer patients. The impact of nutritional advice on the nutritional status of patients, the use of dietary supplements, and the knowledge of phytoestrogens were assessed.

Materials and Methods: The study was conducted between April and July 2016 in the Lublin Oncology Center on a group of 173 female patients undergoing breast cancer treatment. The patients filled out a questionnaire containing 34 open-ended and closed-ended questions. The collected data were processed in Excel and Statistica 5.0 programs, and the results were regarded as significant at P?<?0.05.

Results: The mean age of the evaluated patients was 66.8?±?11.3 years. The duration of disease was significantly correlated with the patients’ nutritional status expressed by the body mass index (P?=?0.0368). The main sources of knowledge about nutrition in cancer care were nurses (29.71%), physicians (12.31%), and nutritionists (13.78%). Patients who received nutritional advice had significantly greater knowledge about phytoestrogens (P?=?0.0001), and they were of the opinion that a diet rich in phytoestrogens was safe (P?=?0.001). More than 85% of the polled subjects used dietary supplements during treatment, and 2/3 of them did so without professional advice. In this study, 73.07% of the respondents regularly monitored their body weight. Patients who did not receive dietary advice less frequently informed their physician about weight changes.

Conclusions: The nutritional status of patients was correlated with access to nutrition and dietary advice during illness. The risk of malnutrition was minimized when patients received and understood educational materials. The patients who did not receive dietary advice more frequently overdosed on dietary supplements. Phytoestrogens were more widely used by patients who regularly attended a dietitian.  相似文献   

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目的 了解医学生学习《健康教育》课程的满意度、需求度现状及差异,为《健康教育》课程优化提供参考。方法 以某医科大学在校临床医学生为研究对象,分析医学生对课程内容的需求度和满意度及二者差异。课程内容包括服药依从性、戒烟干预、合理膳食、心理压力管理、中医康复技术、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育、运动康复指导及健康促进理论。采用频数和构成比指标进行统计描述,采用卡方检验进行健康教育课程学习情况与专业/ 学制之间、相关课程内容学习的需求度与学制的差异,相关课程内容学习需求度与满意度的关联比较采用秩和检验。以P < 0.05 为差异具有统计学意义。结果 戒烟干预、合理膳食、心理压力管理、中医康复技术、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育及健康促进理论八项的学习需求度在长学制医学生与五年制医学生中的总体分布位置不同(U = 2.4、2.2、2.5、2.3、2.4、2.4、2.3、2.0,P 均< 0.05);服药依从性、戒烟干预、合理膳食、心理压力管理、慢性传染病健康教育、急性传染病健康教育、移动健康技术教育及运动康复指导八项的满意度与需求度之间的总体位置分布不同(U = 6.2、5.2、7.2、9.2、5.9、6.1、2.1、3.2,P 均< 0.05);不同学制的医学生对于慢性病人、老年人、孕产妇、传染病人、高危人群和职业暴露人群的健康教育重点关注人群侧重有所不同,其差异具有统计学意义(χ2 = 8.9、14.2、9.9、6.9、23.9、17.8,P 均< 0.05);在教学方式上,不同学制的医学生对于教师课堂讲授和小组讨论的偏好上的差异具有统计学意义(χ2=6.3、9.5,P 均< 0.05)。结论 当前健康教育课程的教学内容和结构未能完全满足不同学制、年级医学生的学习需求,需要对课程教学内容、教学方式和开设时间进行进一步的优化设计。  相似文献   
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Attenuation coefficient estimation has the potential to be a useful tool for placental tissue characterization. A current challenge is the presence of inhomogeneities in biological tissue that result in a large variance in the attenuation coefficient estimate (ACE), restricting its clinical utility. In this work, we propose a new Attenuation Estimation Region Of Interest (AEROI) selection method for computing the ACE based on the (i) envelope signal-to-noise ratio deviation and (ii) coefficient of variation of the transmit pulse bandwidth. The method was first validated on a tissue-mimicking phantom, for which an 18%–21% reduction in the standard deviation of ACE and a 14%–24% reduction in the ACE error, expressed as a percentage of reported ACE, were obtained. A study on 59 post-delivery clinically normal placentas was then performed. The proposed AEROI selection method reduced the intra-subject standard deviation of ACE from 0.72 to 0.39 dB/cm/MHz. The measured ACE of 59 placentas was 0.77 ± 0.37 dB/cm/MHz, which establishes a baseline for future studies on placental tissue characterization.  相似文献   
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