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121.
Narrow‐band imaging (NBI) is an imaging technique for endoscopy using optical filters to narrow the bandwidth of spectral transmittance. Through this narrow spectrum, NBI contrasts surface structure and microvascular architecture of various lesions. In this article we focus on the application of NBI for early‐stage neoplasia in the esophagus, stomach and colon with a three‐step strategy of endoscopic diagnosis: (i) the detection of abnormality; (ii) the differentiation between non‐neoplasia and neoplasia; and (iii) staging for tumor extension and depth of invasion. 相似文献
122.
Maternal choline supplementation differentially alters the basal forebrain cholinergic system of young‐adult Ts65Dn and disomic mice
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Christy M. Kelley Brian E. Powers Ramon Velazquez Jessica A. Ash Stephen D. Ginsberg Barbara J. Strupp Elliott J. Mufson 《The Journal of comparative neurology》2014,522(6):1390-1410
Down syndrome (DS), trisomy 21, is a multifaceted condition marked by intellectual disability and early presentation of Alzheimer's disease (AD) neuropathological lesions including degeneration of the basal forebrain cholinergic neuron (BFCN) system. Although DS is diagnosable during gestation, there is no treatment option for expectant mothers or DS individuals. Using the Ts65Dn mouse model of DS that displays age‐related degeneration of the BFCN system, we investigated the effects of maternal choline supplementation on the BFCN system in adult Ts65Dn mice and disomic (2N) littermates at 4.3–7.5 months of age. Ts65Dn dams were maintained on a choline‐supplemented diet (5.1 g/kg choline chloride) or a control, unsupplemented diet with adequate amounts of choline (1 g/kg choline chloride) from conception until weaning of offspring; post weaning, offspring were fed the control diet. Mice were transcardially perfused with paraformaldehyde, and brains were sectioned and immunolabeled for choline acetyltransferase (ChAT) or p75‐neurotrophin receptor (p75NTR). BFCN number and size, the area of the regions, and the intensity of hippocampal labeling were determined. Ts65Dn‐unsupplemented mice displayed region‐ and immunolabel‐dependent increased BFCN number, larger areas, smaller BFCNs, and overall increased hippocampal ChAT intensity compared with 2N unsupplemented mice. These effects were partially normalized by maternal choline supplementation. Taken together, the results suggest a developmental imbalance in the Ts65Dn BFCN system. Early maternal‐diet choline supplementation attenuates some of the genotype‐dependent alterations in the BFCN system, suggesting this naturally occurring nutrient as a treatment option for pregnant mothers with knowledge that their offspring is trisomy 21. J. Comp. Neurol. 522:1390–1410, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
123.
目的:评价前牙区直接法纤维增强复合桥(FRC bridge)修复单颗切牙缺失伴邻牙松动的牙周炎病例临床应用效果。方法:采用直接法FRC bridge连接所有同颌前牙修复单颗切牙缺失伴邻牙松动的牙周炎病例12例,以弹性义齿修复14例同类病例作为对照,修复后1、6及18个月随访,对临床修复效果以及牙周状况进行评价。结果:修复后1、6或18个月,直接法FRC bridge修复组和对照组解剖外形和边缘适应性均优于弹性义齿修复组(P<0.05);牙周袋探诊深度(PD)及探诊出血指数(BOP)随着观察时间延长而逐渐减小;修复前后PD、BOP、牙齿松动度(TM)差异均存在显著性(P<0.05)。结论:直接法FRC bridge修复单颗切牙缺失伴邻牙松动的牙周炎病例,能达到良好的临床美学修复效果,并可改善邻牙牙周状况。 相似文献
124.
Harish Saluja Vipin Dehane Yogesh Kini Uma Mahindra Prafful Gaikwad 《Journal of maxillofacial and oral surgery》2013,12(3):312-314
Aim of the study was to find out the number of miniplates used by Indian Oral and Maxillofacial Surgeons for parasymphysis fractures. A survey was done among Oral and Maxillofacial Surgeons of India at the 34th annual meeting of Association of Oral and Maxillofacial Surgeons of India. Four questions were given to each individual to find out their opinion regarding use of miniplates in parasymphysis fractures. Eighty-eight per cent of Indian surgeons were in favour of using intra-operative or post-operative intermaxillary fixation. Thirty-eight per cent responded in favour of using single miniplate for parasymphysis fracture instead of using two miniplates. Fifty-four per cent maxillofacial surgeons use various modifications depending on different conditions. Forty-two per cent of maxillofacial surgeons accepted that lower arch bar can be used as a tension band. Use of miniplates for the treatment of parasymphysis fracture varies from centre to centre and from surgeon to surgeon. Though miniplates are best used following Champy’s principle, still many surgeons use single miniplate. Arch bars placed for intermaxillary fixation can be used as a tension band, again eliminating the need for upper plate. 相似文献
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126.
Background and Aim: The aim of this study was to determine whether the use of the narrow band imaging (NBI) system could enhance the accuracy of adenoma detection during an endoscopic examination of the colon and rectum. Methods: MEDLINE, EMBASE, and the Cochrane Library databases were searched along with a hand search of abstracts from relevant conferences up to June 2011. The rates of adenoma and flat adenoma detection, and withdrawal time were analyzed using Review Manager 4.2. Results: A total of 3049 subjects in eight trials were included. Meta‐analysis revealed that there was no statistically significant difference in the rates of adenoma detection between the NBI group and the white light colonoscopy group (pooled relative risk [RR]: 1.09, 95% confidence interval [CI]: 1.00–1.19, P = 0.05). However, after exclusion of high‐definition television modalities, the rate of adenoma detection by NBI was significantly higher than that by white light, particularly for patients with one adenoma (pooled RR 1.36, 95%CI 1.07–1.71, P = 0.02). Endoscopy with the NBI system significantly increased the rate of flat adenoma detection (pooled RR 1.96, 95%CI 1.09–3.52, P = 0.02). However, endoscopy with NBI had longer withdrawal time than that with white light (pooled weighted mean difference: 0.90, 95%CI: 0.38–1.42, P = 0.0006). Conclusions: Endoscopy with NBI seems to improve the detection of flat adenomas, particularly with high‐definition technology, but prolongs the withdrawal time. These results indicate that endoscopy routinely using the NBI system for the surveillance of adenomas may be recommended after the technique is further modified. 相似文献
127.
目的 分析放大窄带成像内镜(M-NBI)下胃窦炎的微形态特征,评价M-NBI用于胃窦炎靶向活检的可行性.方法 以完成M-NBI检查的连续患者69例为研究对象,按NBI内镜下病变黏膜表面形态分型,以M-NBI检查部位活检的组织学结果为金标准,比较黏膜表面形态和组织病理学结果的关系.另取30张图像进行观察者间一致性评价.结果 69例患者共有病变173处,与病理组织学结果进行对比分析.A型以正常部位(89.8%,44/49)为多,B型和C型分别以慢性炎症(53.3%,24/45)和活动性炎症(74.3%,26/35)为多.与A型组相比,B型组(P <0.001)和C型组(P<0.001)的炎症水平显著增加.B+C型预测急慢性炎症的敏感度、特异度和准确度分别为87.5%、78.0%和81.5%;D+E型预测肠上皮化生的敏感度、特异度和准确度分别为83.8%、90.4%和77.5%.观察者间一致性评价结果示Kappa值为0.734[95%CI(0.591 ~0.977)],提示一致性较好.结论 M-NBI下胃黏膜微形态特征与组织学检查结果有较好的相关性,M-NBI检查能够明显地提高对胃窦炎的预测能力. 相似文献
128.
129.
范新宇 《组织工程与重建外科》2013,9(1):56-58
皮肤软组织扩张术是整形外科创面修复的重要方法.组织扩张会引起皮肤软组织面积的增加和皮肤血管的新生.扩张皮肤组织血管的新生过程受多种因素的影响.本文就扩张皮肤血管新生过程的张力、缺氧和生长因子等因素的影响进行综述. 相似文献
130.
王硕华 《中国医学影像技术》2005,21(12):1872-1872
患者女,30岁,G5 P 31,孕前2个月曾行人流术,孕3个月内无上呼吸道病毒感染史,无不适感觉.本次妊娠21周首次行产科常规超声检查.超声所见:宫内胎儿臀位、活动受限,颅骨光环尚完整,颅内结构显示欠清,可见不规则网带状结构连于胎头与羊膜之间,脊柱排列整齐.双侧胸腔内可见液性暗区,心、肺组织受推挤,胎心搏动约150次/分.腹腔内见不规则液性组织,部分胎儿躯干部及肢体周围可见低回声带束缚,其内回声不均、可见无回声区. 相似文献