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61.
In situ endoscopy: New insights to root growth in biopores   总被引:1,自引:0,他引:1  
T. Kautz  U. Köpke 《Plant biosystems》2013,147(2):440-442
Abstract

A flexible videoscope with an outer diameter of 3.8 mm and equipped with a movable tip was used for in situ observation of roots growing in larger‐sized biopores. We were able to display root morphology and position inside of biopores and differentiate four categories of root segments.  相似文献   
62.
Probe-based confocal laser endomicroscopy (CLE) is an emerging optical imaging technology that enables real-time in vivo microscopy of mucosal surfaces during standard endoscopy. With applications currently in the respiratory1 and gastrointestinal tracts,2-6 CLE has also been explored in the urinary tract for bladder cancer diagnosis.7-10 Cellular morphology and tissue microarchitecture can be resolved with micron scale resolution in real time, in addition to dynamic imaging of the normal and pathological vasculature.7The probe-based CLE system (Cellvizio, Mauna Kea Technologies, France) consists of a reusable fiberoptic imaging probe coupled to a 488 nm laser scanning unit. The imaging probe is inserted in the working channels of standard flexible and rigid endoscopes. An endoscope-based CLE system (Optiscan, Australia), in which the confocal endomicroscopy functionality is integrated onto the endoscope, is also used in the gastrointestinal tract. Given the larger scope diameter, however, application in the urinary tract is currently limited to ex vivo use.11 Confocal image acquisition is done through direct contact of the imaging probe with the target tissue and recorded as video sequences. As in the gastrointestinal tract, endomicroscopy of the urinary tract requires an exogenenous contrast agent—most commonly fluorescein, which can be administered intravenously or intravesically. Intravesical administration is a well-established method to introduce pharmacological agents locally with minimal systemic toxicity that is unique to the urinary tract. Fluorescein rapidly stains the extracellular matrix and has an established safety profile.12 Imaging probes of various diameters enable compatibility with different caliber endoscopes. To date, 1.4 and 2.6 mm probes have been evaluated with flexible and rigid cystoscopy.10 Recent availability of a < 1 mm imaging probe13 opens up the possibility of CLE in the upper urinary tract during ureteroscopy. Fluorescence cystoscopy (i.e. photodynamic diagnosis) and narrow band imaging are additional endoscope-based optical imaging modalities14 that can be combined with CLE to achieve multimodal imaging of the urinary tract. In the future, CLE may be coupled with molecular contrast agents such as fluorescently labeled peptides15 and antibodies for endoscopic imaging of disease processes with molecular specificity.  相似文献   
63.
64.
目的:研究鼻内镜手术治疗慢性鼻窦炎的疗效。方法:选取在2008年10月至2010年1月之间来本院进行手术治疗的慢性鼻窦炎患者54例,使用鼻内镜手术进行治疗,作为此次研究的治疗组;而同时选取在同一时期来到本院的38例患者,作为此次研究的对照组采用一般的鼻外径手术治疗。在手术结束以后每位患者均需随访1年,根据患者的恢复情况比较两种手术方法对鼻窦炎的疗效,以上手术方式均根据患者意愿。结果:使用鼻内镜手术进行治疗的患者中治愈的有31例,有效的有18例,而无效的则有5例,总的有效率为90.7%;而采用一般手术的患者中治愈的患者为17例,有效的患者为12例,无效的则有9例,其总的有效率为76.3%;且应用鼻内镜手术的治疗组的并发症发生率小于使用一般手术的对照组,两组患者疗效比较差异有统计学意义(P<0.05)。结论:鼻内镜手术治疗慢性鼻赛炎的疗效确切,安全可靠,值得广大医务工作者在临床上大力推广。  相似文献   
65.
目的:评价胶囊内镜在小肠疾病中的诊断价值,总结胶囊内镜临床应用策略。方法:回顾性分析上海市第一人民医院胃肠镜室2009年7月-2011年4月67例行胶囊内镜检查患者的检查结果,结合其中32名患者双气囊小肠镜检查结果及手术病理,分析胶囊内镜在小肠疾病的检出率,诊断率和不良事件发生率,总结胶囊内镜检查时的注意事项。结果:1例胶囊内镜操作失败,66例受检者检出率80.3%,诊断率为66.7%,发现病变中血管病变为主要诊断,占62.1%,其次为肠道占位(息肉、肿瘤)为14.6%,克罗恩病占10.9%,所有患者均未出现严重不良事件。结论:胶囊内镜在小肠疾病检查中安全,无创,诊断率较高,临床胶囊内镜检查时建议充分肠道准备,实时监控及结合双气囊小肠镜检查。  相似文献   
66.
Objectives: We evaluated demographic characteristics in HIV‐positive patients receiving highly active antiretroviral therapy (HAART) who had upper gastrointestinal (UGI) symptoms requiring UGI endoscopy and compared the findings in patients with and without H. Pylori coinfection. Methods: We prospectively observed all HIV‐infected patients treated with antiretroviral therapy who underwent UGI endoscopy for the first time and were tested for H. pylori from January 2004 to December 2008. Data collected included the following: demographics (age, gender, ethnicity, body mass index [BMI], tobacco use, alcohol intake, and HIV risk behavior); comorbidity (viral hepatitis B or C, any organ dysfunction, or opportunistic disease); medication, including antibiotics, H2 blockers, proton pump inhibitors, and NSAIDs; CD4 cell counts, viral load; symptoms; and endoscopic and histologic diagnoses (H. pylori determined by Giemsa staining). Patients were compared according to H. pylori status (presence vs absence). Results: One hundred and forty‐five patients were evaluated. Compared to patients without H. pylori infection (n = 97), those with H. pylori infection (n = 48) had a significantly higher CD4 cell count (p = .008), were more likely to be heterosexual (p = .047), had a higher BMI (p = .027), had a greater incidence of duodenal ulcers (p = .005), had lower viral loads (p < .01), were less likely to have received macrolide antibiotics in the last 3 months (p = .00), and had less comorbidity (p = .03). They were also more frequently of Black African than Caucasians. In multivariate analysis, being heterosexual and having a low viral load were independently associated with an increased risk of having H. Pylori coinfection. Conclusion: In the antiretroviral therapy era, HIV–H. pylori coinfection is associated with a greater incidence of duodenal ulcers and higher CD4 counts, higher BMI, less comorbidity, and less frequent use of macrolides.  相似文献   
67.
Quantification of the mucosa oxygenation levels during Endoscopic imaging provides useful physiological/diagnostic information. In this work a method for non‐contact quantification of the oxygen saturation index during Endoscopic imaging using three discrete spectral‐band in the blue, the green, and the red parts of the spectrum (RGB bands) has been investigated. The oxygen saturation index (TOI_rgb) was calculated from the three discrete RGB spectral bands using diffusion approximation modeling and least‐square analysis. A parametric study performed to identify the optimum band width for each of the three spectral bands. The quantification algorithm was applied to in vivo images of the endobronchial mucosa to calculate (TOI_rgb) from selected areas within the image view. The results were compared to that obtained from the full visible spectral (470–700 nm, 10 nm) measurements. The analysis showed that a band width of at least 20 nm in the blue and the green is required to obtain best results. The results showed that the method provides accurate estimation of the oxygenation levels with about 90% accuracy compared to that obtained using the full spectra. The results suggest the potential of quantifying the oxygen saturation levels from the three narrow RGB spectral bands/images. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
68.
Currently the most sensitive method for localizing lung cancers in central airways is autofluorescence bronchoscopy (AFB) in combination with white light bronchoscopy (WLB). The diagnostic accuracy of WLB + AFB for high grade dysplasia (HGD) and carcinoma in situ is variable depending on physician's experience. When WLB + AFB are operated at high diagnostic sensitivity, the associated diagnostic specificity is low. Raman spectroscopy probes molecular vibrations and gives highly specific, fingerprint‐like spectral features and has high accuracy for tissue pathology classification. In this study we present the use of a real‐time endoscopy Raman spectroscopy system to improve the specificity. A spectrum is acquired within 1 second and clinical data are obtained from 280 tissue sites (72 HGDs/malignant lesions, 208 benign lesions/normal sites) in 80 patients. Using multivariate analyses and waveband selection methods on the Raman spectra, we have demonstrated that HGD and malignant lung lesions can be detected with high sensitivity (90%) and good specificity (65%).

  相似文献   

69.
目的:探讨急诊内镜下止血联合生长抑素治疗上消化道出血的疗效。方法:选取了100例上消化道出血患者,按随机数字表法分为两组,对照组(48例)给予常规止血措施,观察组(52例)行急诊内镜下止血联合生长抑素治疗上消化道出血,通过观察并记录两组患者疗效、不同病灶大小的治疗成功率及临床症状改善情况,评估急诊内镜下止血联合生长抑素治疗上消化道出血的疗效。结果:观察组患者治疗有效率88.5%,对照组患者治疗有效率70.8%,观察组治疗有效率高于对照组(P0.05);观察组对不同病变大小止血成功率均高于对照组(P0.05);从止血治疗成功率来看,随着病变大小的增加,止血成功率有所下降,观察组患者住院时间,大便潜血转阴,呕血消失时间均短于对照组(P0.05),并且术后再出血率也低于对照组患者(P0.05)。结论:急诊内镜下止血联合生长抑素对上消化道出血具有良好的治疗效果,能明显改善上消化道出血症状,缩短患者住院时间,但对病变范围较大的上消化道出血,治疗效果有限。  相似文献   
70.
目的:评估比较窄带成像技术联合放大内镜(narrow band imaging-magnifying endoscopy,NBI-ME)在早期胃癌诊断中价值。方法:115例早期胃癌患者行NBI-ME观察,采集照片并做出内镜下诊断,于病灶最明显处取活检并行病理检查。所有患者接受内镜下治疗,术后行病理活检。分别计算NBI-ME、内镜活检诊断早期胃癌的敏感度、特异度、阳性预测值、阴性预测值、准确率。结果:115例患者纳入本研究,最终术后切除病理示低级别上皮内瘤变(low-grade neoplasia,LGIN)16例,高级别上皮内瘤变(high-grade neoplasia,HGIN)30例,分化型胃癌59例,未分化型胃癌10例。NBI-ME诊断早期胃癌的敏感度、特异度、阳性预测值、阴性预测值、准确率分别为98.0%、81.3%、97.0%、86.7%、95.7%,内镜活检的对应值分别为82.8%、87.5%、97.6%、45.2%、83.5%。NBI-ME诊断早期胃癌的敏感度及准确率均明显高于内镜活检(P0.05)。结论:NBI-ME对早期胃癌具有较高诊断价值。  相似文献   
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