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Single‐shot speckle correlation fluorescence microscopy in thick scattering tissue with image reconstruction priors 下载免费PDF全文
Deep tissue imaging in the multiple scattering regime remains at the frontier of fluorescence microscopy. Speckle correlation imaging (SCI) can computationally uncover objects hidden behind a scattering layer, but has only been demonstrated with scattered laser illumination and in geometries where the scatterer is in the far field of the target object. Here, SCI is extended to imaging a planar fluorescent signal at the back surface of a 500‐μm‐thick slice of mouse brain. The object is reconstructed from a single snapshot through phase retrieval using a proximal algorithm that easily incorporates image priors. Simulations and experiments demonstrate improved image recovery with this approach compared to the conventional SCI algorithm. 相似文献
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摘要 目的:探讨慢性肾功能不全患者应用三维斑点追踪技术对其左心室收缩功能和右心室功能的评估价值。方法:选择我院收治的慢性肾功能不全患者82例,根据患者肾功能将其分为轻度慢性肾功能不全组[慢性肾脏病(CKD) 2期,47例],中-重度慢性肾功能不全组(CKD 3~5期,35例),另选取同期医院体检的健康志愿者30例作为对照组,应用二维超声及三维斑点追踪技术检测各组心脏指标,比较三组二维超声指标、三维斑点追踪技术指标,应用受试者工作特征(ROC)曲线分析三维斑点追踪技术对患者左心室收缩功能和右心室功能的评估价值。结果:中-重度慢性肾功能不全组室间隔舒张末期厚度(IVSTd)、肺动脉收缩压(PASP)显著高于轻度慢性肾功能不全组、对照组,右心室面积变化分数(RVFAC)、组织运动三尖瓣环位移(TAPSE)、左心室射血分数(LVEF)显著低于轻度慢性肾功能不全组、对照组(P<0.05)。中-重度慢性肾功能不全组左室整体圆周收缩期峰值应变(LGCS)、左室整体纵向收缩期峰值应变(LGLS)、右室整体圆周收缩期峰值应变(RGCS)右室整体纵向收缩期峰值应变(RGLS)、显著高于轻度慢性肾功能不全组、对照组,左室整体径向收缩期峰值应变(LGRS)、三维左室射血分数(3D-LVEF)、右室整体径向收缩期峰值应变(RGRS)、三维右室射血分数(3D-RVEF)显著低于轻度慢性肾功能不全组、对照组(P<0.05)。ROC曲线分析显示,三维斑点追踪技术对慢性肾功能不全患者左心室收缩功能和右心室功能的评估价值较高。结论:三维斑点追踪技术可以准确检测心脏的纵向运动、圆周运动、径向运动,为临床早期发现慢性肾功能不全患者的心脏功能异常提供依据。 相似文献
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Laser speckle contrast imaging (LSCI) is a full‐field optical imaging method for monitoring blood flow and vascular morphology with high spatiotemporal resolution. However, due to the limited depth of field of optical system, it is difficult to capture a clear blood flow image with all blood vessels focused, especially for the non‐planar biological tissues. In this study, a multi‐focus image fusion method based on contourlet transform is introduced to reduce the misfocus effects in LSCI. The experimental results suggest that this method can provide an all‐in‐focus blood flow image, which is convenient to observe the blood vessels. 相似文献
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Itay Remer Lorraine F. Pierre‐Destine David Tay Linnie M. Golightly Alberto Bilenca 《Journal of biophotonics》2019,12(1)
Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection associated with impaired cerebral blood flow. Visualization of the eye vasculature, which is embryologically derived from that of the brain, is used clinically to diagnose the syndrome. Here, we introduce camera‐phone laser speckle imaging as a new tool for in vivo, noncontact two‐dimensional mapping of blood flow dynamics in the experimental cerebral malaria (ECM) murine model of Plasmodium berghei ANKA. In a longitudinal study, we show that the camera‐phone imager can detect an overall decrease in the retinal blood‐flow‐speed (BFS) as ECM develops in P. berghei ANKA infected mice, with no similar change observed in uninfected control mice or mice infected with a non‐ECM inducing strain (P. berghei NK65). Furthermore, by analyzing relative alterations in the BFS of individual retinal vessels during the progression of ECM, we illustrate the strength of our imager in identifying different BFS‐change heterogeneities in the retinas of ECM and uninfected mice. The technique creates new possibilities for objective investigations into the diagnosis and pathogenesis of CM noninvasively through the eye. The camera‐phone laser speckle imager along with measured spatial blood perfusion maps of the retina of a mouse infected with P. berghei ANKA—a fatal ECM model—on different days during the progression of the infection (top, day 3 after infection; middle, day 5 after infection; and bottom, day 7 after infection). 相似文献
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Actin is a multifunctional eukaryotic protein with a globular monomer form that polymerizes into a thin, linear microfilament in cells. Through interactions with various actin-binding proteins (ABPs), actin plays an active role in many cellular processes, such as cell motility and structure. Microscopy techniques are powerful tools for determining the role and mechanism of actin–ABP interactions in these processes. In this article, we describe the basic concepts of fluorescent speckle microscopy, total internal reflection fluorescence microscopy, atomic force microscopy, and cryoelectron microscopy and review recent studies that utilize these techniques to visualize the binding of actin with ABPs. 相似文献
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