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91.
Respiratory cytology continues to play a central role in the diagnosis and staging of thoracic malignancy, although over time indications have changed. Historically, sputum cytology and endobronchial brushings and washings figured prominently, but with the advent of endobronchial and endoscopic ultrasound much greater emphasis is placed on fine needle aspirates from lymph nodes. The advent of targeted sequencing panels for genomic profiling to identify driver mutations and PD-L1 directed immunotherapy means that there is a need to extract increasing amounts of diagnostic and predictive information from ever smaller amounts of diagnostic material. Recent work has demonstrated that cytology samples are well suited to delivering the information required, but in order to understand the limitations of clinical and laboratory techniques, a close working relationship between pathologist and thoracic oncologist is needed to optimise sample procurement and utilisation. 相似文献
92.
Trace Determination of Lead,Chromium and Cadmium in Herbal Medicines Using Ultrasound‐Assisted Emulsification Microextraction Combined with Graphite Furnace Atomic Absorption Spectrometry
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94.
《Microbes and infection / Institut Pasteur》2015,17(5):353-359
Antimicrobial peptides are multifunctional effector molecules of innate immunity. In this study we investigated whether endothelial cells actively contribute to innate defense mechanisms by expression of antimicrobial peptides. We therefore stimulated human umbilical vein endothelial cells (HUVEC) with inflammatory cytokines, Th17 cytokines, heat-inactivated bacteria, bacterial conditioned medium (BCM) of Staphylococcus aureus and Streptococcus sanguinis, and lipoteichoic acid (LTA). Stimulation with single cytokines induced discrete expression of human β-defensin 3 (hBD3) by IFN-γ or IL-1β and of ribonuclease 7 (RNase7) by TNF-α without any effects on LL-37 gene expression. Stronger hBD3 and RNase7 induction was observed after combined stimulation with IL-1β, TNF-α and IFN-γ and was confirmed by high hBD3 and RNase7 peptide levels in cell culture supernatants. In contrast, Th17 cytokines or stimulation with LTA did not result in AMP production. Moreover, only BCM of an invasive S. aureus bacteremia isolate induced hBD3 in HUVEC. We conclude that endothelial cells actively contribute to prevent dissemination of pathogens at the blood-tissue-barrier by production of AMPs that exhibit microbicidal and immunomodulatory functions. Further investigations should focus on tissue-specific AMP induction in different endothelial cell types, on pathogen-specific induction patterns and potentially involved pattern-recognition receptors of endothelial cells. 相似文献
95.
目的:探讨跟骨强度指数与其影响因素的相关性。方法:共入选1024例体检人员。(1)通过Achilles定量超声(QUS)系统测量左跟骨强度指数;(2)使用RGC-120型体重秤测量身高、体重并计算体重指数;(3)通过问卷调查收集体检人员年龄、膳食、运动、吸烟、饮酒等影响因素的相关资料;(4)将各影响因素与跟骨强度指数进行相关分析和多元逐步回归分析。结果:(1)直线相关分析结果显示,跟骨强度指数与身高、体重、体重指数、饮用牛奶年数、运动年数呈正相关(;2)多因素逐步回归分析显示,跟骨强度指数仅与体重指数、运动年数具有显著的回归效果。结论:体重指数与运动年数是跟骨强度指数的独立影响因素,对骨质疏松的诊断与预防具有重要的意义。 相似文献
96.
Recently, cichoric acid production from hairy roots of Echinacea purpurea was significantly improved by ultrasound stimulation in an airlift bioreactor. In this article, the possible mechanism on ultrasound-intensified hairy root culture of E. purpurea in the bioreactor was elucidated with the help of computational fluid dynamics (CFD) simulation, membrane permeability detection, dissolved oxygen concentration detection, confocal laser-scanning microscopy (LSM) observation, and phenylalanine ammonium lyase (PAL) activity analysis. The CFD model developed in Part I was used to simulate the hydrodynamics and oxygen mass transfer in hairy root bioreactor culture stimulated by ultrasound. A dynamic mesh model combined with a changing Schmidt number method was used for the simulation of the ultrasound field. Simulation results and experimental data illustrated that ultrasound intensified oxygen mass transfer in the hairy root clump, which subsequently stimulated root growth and cichoric acid biosynthesis. Ultrasound increased the hairy root membrane permeability, and a high root membrane permeability of 0.359 h(-1) was observed at the bottom region in the bioreactor. LSM observation showed that the change in the membrane permeability recovered to normal in the further culture after ultrasound stimulation. PAL activity in the hairy roots was stimulated by ultrasound increase and was correlated well to cichoric acid accumulation in the hairy roots of E. purpurea. 相似文献
97.
施冬梅路永涛徐哲于德香 《现代生物医学进展》2011,11(4):742-744
目的:探讨二维及彩色多普勒超声在乳腺癌诊断方面的临床应用价值。方法:对60例经手术病理证实的乳腺肿块病例的二维及彩色多普勒超声检查与病理结果进行回顾性分析。结果:乳腺癌诊断中,大多数恶性肿块表现为形态不规则、边缘粗糙、边界不清、内部回声不均匀、后方回声衰减。恶性肿块的血流显示率明显高,血流分布以Ⅱ、Ⅲ级为主。结论:二维声像图及彩色多普勒在乳腺癌诊断方面有较高的临床应用价值。由于良恶性肿物的影像互有交叉,其诊断符合率并非是100%。须两者联合应用,综合分析,方可提高超声对乳腺良恶性肿块的诊断符合率。 相似文献
98.
Interrelation between HeLa-S3 cell transfection and hemolysis in red blood cell suspension using pulsed ultrasound of various duty cycles 总被引:1,自引:0,他引:1
We have studied the in vitro transfection of a plasmid DNA with the lacZ gene to HeLa-S3 cells and hemolysis in a red blood cell (RBC) suspension under pulsed ultrasound with duty cycles of 10, 20 and 30% using a digital sonifier at a frequency of 20 kHz and an intensity of 6.2 W/cm2 on the surface of a horn tip. Cultured HeLa-S3 cells in suspension were exposed to pulsed ultrasound for an apparent exposure time t from 0 to 60 s. HeLa-S3 viability decreased as a single exponential function of the total exposure time t=t with a common time constant =3.8 s for three duty cycles. Transfection was evaluated by counting the number of -galactosidase(-Gal)-positive cells relative to the total number of cells. Pulsed ultrasound provided an enhanced transfer of the -Gal plasmid to HeLa-S3 cells, 3.4-fold as compared with that in the case of the control. The optimal transfection efficiencies were 0.75, 0.80 and 0.74% near t= with =10, 20 and 30%, respectively. The number ratio of -Gal-positive cells to the surviving cells after exposure increased with t according to a modified logistic equation. The degree of hemolysis also increased exponentially with t at a time constant =0/ for the RBC suspension in physiological saline at a hematocrit concentration of 0.5% with 0=0.9 s. Thus the total exposure time for the optimal transfection efficiency was , that is, nearly four times of 0. Hemolysis in the RBC suspension may be a useful model for determining optimal transfection by pulsed ultrasound of various duty cycles. 相似文献
99.
超声破裂载基因微泡增强心肌细胞报告基因的转染与表达 总被引:1,自引:0,他引:1
目的:通过超声破裂载基因微泡介导报告基因心肌细胞转染,探讨其能否增强心肌细胞外源基因转染与表达.方法:以β-galactosidase质粒为报告基因,将其与自制氟碳气体微泡粘附,制备载基因微泡.利用诊断性超声破裂微泡进行体外心肌细胞基因转染;以磷酸钙共沉淀转染为阳性对照并将其以不同方式与超声破裂微泡技术联合应用,以期进一步增强基因转染效果.分别采用原位染色及酶学定量检测β-galactosidase表达水平,同时进行细胞活性检测.结果:超声破裂载基因氟碳气体微泡(PESDA)转染组心肌细胞β-galactosidase表达水平可达单纯质粒转染组60倍(P<0.01).磷酸钙共沉淀转染3.67倍(P<0.01)超声强度、微泡浓度对超声破裂介导基因转染效果有明显影响.超声破裂微泡技术与磷酸钙共沉淀联合应用可进一步提高报告基因的表达(P<0.05),即使在磷酸钙转染后6 h,超声破裂微泡仍能明显增强报告的基因的表达(P<0 05).结论:超声破裂微泡技术是一种高效基因转染方法,其不但能增加DNA转染,而且增强入胞后基因的表达.超声破裂微泡与其它基因转染技术联合应用能进一步增加基因转染效率. 相似文献
100.
超声彩色血流成像的计算机快速仿真方法 总被引:2,自引:0,他引:2
研究超声彩色血流成像的快速仿真方法,克服原先仿真方法非常耗时的缺点。方法超声彩色血流成像计算机仿真中,血流信号是对成像区间内所有点散射体的回波信号累加而得到的。通过引入新的等效散射体模型,可以大大降低散射体的密度,从而减少计算回波信号所需时间。在计算机上用Matlab编程来进行仿真实验,对以往仿真方法和基于等效散射体模型方法的性能进行比较。结果实验表明:基于等效散射体模型的仿真,在保证相同流速精度的前提下,仿真速度比传统方法提高了10倍以上。结论基于等效散射体模型的仿真方法能极大地提高超声彩色血流成像的仿真速度,可以为超声彩色血流成像的方法研究提供便利。 相似文献