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231.
Gargi Sharma Oana-Maria Thoma Katharina Blessing Robert Gal Maximilian Waldner Kanwarpal Singh 《Journal of biophotonics》2021,14(2):e202000324
Multimodal low-cost endoscopy is highly desirable in poor resource settings such as in developing nations. In this work, we developed a smartphone-based low-cost, reusable tethered capsule endoscopic platform that allows white-light, narrowband, and fluorescence/autofluorescence imaging of the esophagus. The ex-vivo studies of swine esophagus were performed and compared with a commercial endoscope to test the white-light imaging capabilities of the endoscope. The efficacy of the capsule for narrow-band imaging was tested by imaging the vascularization of the tongue. To determine the autofluorescence/fluorescence capability of the endoscope, fluorescein dye with different concentrations was imaged. Furthermore, swine esophagus injected with fluorescein dye was imaged using the fluorescence/autofluorescence and the white-light imaging modules, ex-vivo. The overall cost of the capsules is approximately 12 €, 15 €, and 42 € for the white light imaging, the narrow-band imaging, and the fluorescence/autofluorescence imaging respectively. In addition, the cost of the laser source module required for the narrow-band imaging and the fluorescence/autofluorescence imaging is approximately 218 €. This device will open the possibility of imaging the esophagus in underprivileged areas. 相似文献
232.
目的:探讨窄带成像内镜(NBI)、染色内镜及常规内镜模式鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的应用价值。方法:选择2017年2月至2019年3月西安市中心医院消化科收治的结直肠增生性病变患者,均行NBI、染色内镜、常规内镜检查。比较三种模式图像清晰度以及鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的效能。结果:NBI、染色内镜模式图像质量评分分布优于常规内镜(P<0.05),NBI图像质量评分分布优于染色内镜模式(P<0.05)。以病理结果为准,常规内镜结直肠增生性病变检出率73.13%,NBI 91.04%,染色内镜96.26%,NBI、染色内镜结直肠增生性病变检出率高于常规内镜(P<0.05),NBI、染色内镜比较无统计学差异(P>0.05)。NBI模式下检测NBI分型与病理组织学结果一致性较好(kappa值=0.801,P<0.05)。NBI、染色内镜诊断肿瘤性结直肠增生性病变的灵敏度、特异度、阳性预测值、阴性预测值、准确度均明显高于常规内镜,染色内镜、NBI、常规内镜诊断肿瘤性结直肠增生性病变的曲线下面积(AUC)分别为0.844(95%CI:0.812~0.956)、0.921(95%CI:0.860~0.982)、0.750(95%CI:0.651~0.848)。结论:NBI、染色内镜在鉴别非肿瘤性和肿瘤性结直肠增生性病变方面效能相似,均优于常规内镜,NBI分型与病理组织学结果一致性高,更适合结直肠增生性病变的鉴别诊断。 相似文献
233.
Fine surface structure of enterotoxemic Escherichia coli O139:K12 strains associated with swine edema disease 总被引:1,自引:0,他引:1
The fine structure of the cell surface of seven enterotoxemic Escherichia coli (ETEEC) O139:K12 strains isolated from piglets with edema disease were examined electron microscopically using both the negative-staining
method and the freeze-substitution fixation method. Densely packed, fine fibers were observed; they consisted of a capsule
layer approximately 25 nm thick around the cell surfaces of strains 107/86, IW-2, ED-3, ED-43, and ED-61, all of which have
a capacity to adhere strongly to HEp-2 cells. In contrast, no such structure was observed on the surface of strains RK-O139
or ED-1, both of which adhere only weakly to HEp-2 cells. These results suggest that the capsule structure might be associated
with the ability to adhere to HEp-2 cells and, as a result, also potentially play some role in ETEEC infection.
Received: 29 April 1996 / Accepted: 13 August 1996 相似文献