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作为术中导航的新兴领域,近红外荧光(near-infrared fluorescence,NIRF)成像技术能借助荧光探针对特定的生物组织进行显像,从而在外科手术中实时获取血管、淋巴管和特定组织的视觉信息,从而发现传统方法无法识别的微小灶,正确显示肿瘤切缘,帮助外科医生进行术中决策。该技术由于其操作简单,快速实时,安全无害,具有良好的应用前景。本文将就NIRF成像技术的基本原理,在实时引导肿瘤切除,前哨淋巴结定位,保护正常解剖结构等方面的临床进展进行综述,并且讨论了该技术的局限性和优势并展望其应用前景。 相似文献
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High Temperamental Negative Affectivity in early childhood has been found to predict later emotion dysregulation. While much work has been conducted to separately probe bio-behavioral systems associated with Negative Affectivity, very little work has examined the relations among multiple systems across age. In this study, we use multi-modal methods to index neurobiological systems associated with Negative Affectivity in 53 4-7-year-old children. Prefrontal activation during emotion regulation was measured using functional near-infrared spectroscopy over the lateral prefrontal cortex (PFC) while children played a game designed to elicit frustration in Social (Happy and Angry faces) and Nonsocial contexts. Gaze behaviors while free-viewing Happy and Angry faces were also measured. Finally, Negative Affectivity was indexed using a score composite based on factor analysis of parent-reported temperament. Using mixed-effects linear models, we found an age-dependent association between Negative Affectivity and both PFC activation during frustration and fixation duration on the mouth area of Happy faces, such that older children high in Negative Affectivity spent less time looking at the mouths of Happy faces and had lower PFC activation in response to frustration (ps<0.034). These results provide further insight to how Negative Affectivity may be associated with changes in affective neurobiological systems across early childhood. 相似文献
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Martina Giovannella Bjrn Andresen Julie B Andersen Sahla El-Mahdaoui Davide Contini Lorenzo Spinelli Alessandro Torricelli Gorm Greisen Turgut Durduran Udo M Weigel Ian Law 《Journal of cerebral blood flow and metabolism》2020,40(10):2055
Diffuse correlation spectroscopy (DCS) can non-invasively and continuously asses regional cerebral blood flow (rCBF) at the cot-side by measuring a blood flow index (BFI) in non-traditional units of cm2/s. We have validated DCS against positron emission tomography using 15O-labeled water (15O-water PET) in a piglet model allowing us to derive a conversion formula for BFI to rCBF in conventional units (ml/100g/min). Neonatal piglets were continuously monitored by the BabyLux device integrating DCS and time resolved near infrared spectroscopy (TRS) while acquiring 15O-water PET scans at baseline, after injection of acetazolamide and during induced hypoxic episodes. BFI by DCS was highly correlated with rCBF (R = 0.94, p < 0.001) by PET. A scaling factor of 0.89 (limits of agreement for individual measurement: 0.56, 1.39)×109× (ml/100g/min)/(cm2/s) was used to derive baseline rCBF from baseline BFI measurements of another group of piglets and of healthy newborn infants showing an agreement with expected values. These results pave the way towards non-invasive, cot-side absolute CBF measurements by DCS on neonates. 相似文献
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《Vaccine》2021,39(46):6805-6812
Adjuvants are essential for ensuring the efficacy of modern vaccines. Considering frequent local and systemic adverse reactions, research into the development of safer and more effective adjuvants is being actively conducted. In recent years, the novel concept of laser vaccine adjuvants, which use the physical energy of light, has been developed. For long, light has been known to affect the physiological functions in living organisms. Since the development of lasers as stable light sources, laser adjuvants have evolved explosively in multiple ways over recent decades. Future laser adjuvants would have the potential not only to enhance the efficacy of conventional vaccine preparations but also to salvage candidate vaccines abandoned during development because of insufficient immunogenicity or owing to their inability to be combined with conventional adjuvants. Furthermore, the safety and efficacy of non-invasive laser adjuvants make them advantageous for vaccine dose sparing, which would be favorable for the timely and equitable global distribution of vaccines. In this review, we first describe the basics of light–tissue interactions, and then summarize the classification of lasers, the history of laser adjuvants, and the mechanisms by which different lasers elicit an immune response. 相似文献
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比较宁夏乌拉尔甘草(以下均简称甘草)中基于指标成分含量的色谱鉴别和基于近红外光谱的光谱鉴别差异,建立快速有效鉴别宁夏野生和栽培甘草的方法。采用HPLC和紫外光谱法测定9批野生甘草和14批栽培甘草中甘草苷、甘草酸和总黄酮的含量并采集其近红外光谱信息。结果显示,基于指标成分定量的色谱鉴别无法有效鉴别宁夏野生和栽培甘草,近红外光谱结合聚类分析和主成分分析能够直观、快速、有效鉴别宁夏野生和栽培甘草样品,为甘草生长方式的鉴别及应用研究提供有效方法。同时,为甘草的品种、产地及规格等方面的鉴别提供了研究思路。 相似文献