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排序方式: 共有922条查询结果,搜索用时 15 毫秒
1.
Yuanqing Yao Jun Qian Shunkang Rong Yuwen Huang Bo Xiong Gang Yang Dengqing Zhang Shimin Deng Jie Tan Que Zhu Changming Deng Dichuan Liu Haitao Ran Zhigang Wang Jing Huang 《Ultrasound in medicine & biology》2019,45(2):490-499
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases. 相似文献
2.
Quantitative chemical exchange saturation transfer (qCEST) MRI – omega plot analysis of RF‐spillover‐corrected inverse CEST ratio asymmetry for simultaneous determination of labile proton ratio and exchange rate 下载免费PDF全文
Renhua Wu Gang Xiao Iris Yuwen Zhou Chongzhao Ran Phillip Zhe Sun 《NMR in biomedicine》2015,28(3):376-383
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
3.
肾癌伴下腔静脉癌栓的诊断及治疗(附11例报告) 总被引:1,自引:0,他引:1
报告11例肾细胞癌伴下腔静脉癌栓患者,男9例,女2例;右侧8例,左侧3例。临床症状:血尿9例,腹部肿物2例,仅1例出现下肢水肿、腹壁浅静脉扩张。全部病人均经CT扫描或CT和MRI检查明确诊断。10例经上腹正中或胸腹联合切口取出癌栓连同患肾一并切除。5例术前无其它部位转移者术后平均存活5年2个月,1例术后2个月死亡,2例术前肾蒂淋巴结及肾周脂肪侵犯者中1例存活2年5个月死于非肿瘤疾病,1例目前已存活3年1个月尚在,2例失访。本组腔静脉癌栓发生率占同期肾癌病人的2.7%。本组CT与MRI相结合应用诊断符合率为980%。 相似文献
4.
不能切除肿瘤的恶性梗阻性黄疸的外科姑息治疗方法繁多,本文介绍自1989年以来,采取开腹经不同途径的带支撑导管胆肠内引流的方法治疗30例,减黄确切,尚对7例高位胆管癌在解除胆道梗阻的基础上行术后(192)Ir和(60)Co联合放疗,提高了病人生存质量及延长了生命。 相似文献
5.
人和大鼠腰椎关节突关节的SP能神经纤维的分布 总被引:2,自引:0,他引:2
目的:证实支配腰椎关节突关节的神经支配和化学性质,方法:用逆行荧光素标记结合免疫组化法,研究7只大鼠腰部脊神经节细胞的周围突分支投射到腰椎关节突关节及其递质性质以及3例人腰椎关节突关节囊上神经末梢的化学性质,结果:发现大鼠一侧L5和L6之间的关节突关节受同侧L2-5节段的脊神经节的部分细胞周围突分支支配,其中有33.399%的中型和小型细胞为中SP能免疫反应阳性,人的关节突关节囊含有SP阳性的神经 相似文献
6.
The open reading frame 3 (ORF3) of the severe acute respiratory syndrome coronavirus (SARS-CoV) genome encodes a predicted 154-amino acid protein, which lacks similarities to any known protein, and is named 3b. In this study, it was shown that 3b protein was predominately localized to nucleus with EGFP tag at its N- or C-terminus. The localization patterns were similar in different transfected cells. Immuno-fluorescence assay revealed that 3b protein was co-localized well with C23 in nucleolus. C23, B23 and fibrillarin all are important nucleolar proteins, which localize in the region of the nucleolus. Co-transfection of p3b-EGFP with pC23-DsRed, pB23-DsRed and pfibrillarin-DsRed further confirmed 3b's nucleolus localization. With construction of serial truncated mutants of 3b, a region (residues 134-154 aa) responsible for nucleolar localization was determinated in 3b protein. These results provide a new insight for further functional studies of SARS-CoV 3b protein. 相似文献
7.
8.
目的 了解新疆某铀矿山周边食品的放射性水平,补充新疆食品放射性核素基线数据库,分析放射性核素含量,估算居民由膳食摄入所致内照射剂量。方法 2018—2020年采集食品样品6类71份,用高纯锗γ能谱仪对感兴趣核素238U、232Th、226Ra、40K和137Cs的比活度进行测量、统计、分析,并对其所致居民年有效剂量进行估算。结果 2018—2020年食品样品中均未检出核素238U,其余放射性核素的平均活度浓度和检出率分别为232Th:0.428 ±0.038 Bq/kg(18.3%)、226Ra:0.477 ±0.063 Bq/kg(38%)、40K:162 ±7 Bq/kg(100%)、137Cs:0.071 ±0.011 Bq/kg(29.6%),居民因食品放射性核素所致年有效剂量约为0.198 mSv。结论 新疆某含铀矿山周边食品的放射性水平在国家标准限值以内,居民因膳食所致年平均有效剂量与(UNSCEAR)2000年报告相符合,食品样品中检出的人工放射性核素137Cs的含量不会对居民健康造成危害。 相似文献
9.
将新生大鼠的脊神经节与心肌细胞进行联合培养,用相差显微镜和Holmes还原银染色观察了神经元的生长以及神经纤维与心肌细胞之间的关系。脊神经节与心肌细胞联合培养72 ̄96小时可观察到神经纤维终止于搏动的心肌细胞表面。神经节组织块周围有许多神经纤维在心肌细胞表面相互交织成网状。交叉的神经纤维相互粘连在一起,终止于搏动的心肌细胞表面的一条神经纤维移动将会牵动邻近的交叉神经纤维网。Holmes还原银染色结 相似文献
10.