Name: visualizing membrane ruffle formation using scanning electron microscopy
Uploaded: 2021-05-27T15:00:00
Description: Watch this Scientific Journal Video about Visualizing Membrane Ruffle Formation using Scanning Electron Microscopy at JoVE.com

作者感谢Libby Perry（奥古斯塔大学）在SEM样品制备方面的帮助。这项工作得到了美国国立卫生研究院[R01HL139562（G.C.）和K99HL146954（B.S.）]和美国心脏协会[17POST33661254（B.S.）]的支持。

注意：以下是用于使用SEM显微镜定量RAW 264.7巨噬细胞中膜褶皱形成的通用方案。可能需要针对不同的细胞类型进行优化。
1. 细胞系和细胞培养
<ol><li>在Dulbecco的改良鹰培养基（DMEM）中生长RAW 264.7巨噬细胞，并在37°C和5%CO2的加湿培养箱中补充10%（体积/体积）热灭活胎牛血清（FBS），100 IU / mL青霉素和100μg/ mL链霉素。每隔一天更换一次生长培养基。</li>
	<li>当细胞融合...

<ol>
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L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruffles+induced+by+Salmonella+and+other+stimuli+direct+macropinocytosis+of+bacteria.">Ruffles induced by Salmonella and other stimuli direct macropinocytosis of bacteria.</a> Nature. 364 (6438), 639-642 (1993).</li><li>Mercer, J., Helenius, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Virus+entry+by+macropinocytosis.">Virus entry by macropinocytosis.</a> Nature Cell Biology. 11 (5), 510-520 (2009).</li><li>Liu, X., Ghosh, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracellular+nanoparticle+delivery+by+oncogenic+KRAS-mediated+macropinocytosis.">Intracellular nanoparticle delivery by oncogenic KRAS-mediated macropinocytosis.</a> International Journal of Nanomedicine. 14, 6589-6600 (2019).</li><li>Desai, A. S., Hunter, M. R., Kapustin, A. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+macropinocytosis+for+intracellular+delivery+of+therapeutic+nucleic+acids+to+tumour+cells.">Using macropinocytosis for intracellular delivery of therapeutic nucleic acids to tumour cells.</a> Philosophical Transactions of Royal Society of London B: Biological Sciences. 374 (1765), 20180156 (2019).</li><li>Lin, H. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+novel+macropinocytosis+inhibitors+using+a+rational+screen+of+Food+and+Drug+Administration-approved+drugs.">Identification of novel macropinocytosis inhibitors using a rational screen of Food and Drug Administration-approved drugs.</a> British Journal of Pharmacology. 175 (18), 3640-3655 (2018).</li><li>Singla, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PKC&#948;-Mediated+Nox2+Activation+Promotes+Fluid-Phase+Pinocytosis+of+Antigens+by+Immature+Dendritic+Cells.">PKC&#948;-Mediated Nox2 Activation Promotes Fluid-Phase Pinocytosis of Antigens by Immature Dendritic Cells.</a> Frontiers in Immunology. 9, 537 (2018).</li><li>Ivanov, A. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacological+inhibition+of+endocytic+pathways:+is+it+specific+enough+to+be+useful.">Pharmacological inhibition of endocytic pathways: is it specific enough to be useful.</a> Methods in Molecular Biology. 440, 15-33 (2008).</li><li>Araki, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+3-methyladenine+on+the+fusion+process+of+macropinosomes+in+EGF-stimulated+A431+cells.">Effect of 3-methyladenine on the fusion process of macropinosomes in EGF-stimulated A431 cells.</a> Cell Structure and Function. 31 (2), 145-157 (2006).</li><li>Koivusalo, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amiloride+inhibits+macropinocytosis+by+lowering+submembranous+pH+and+preventing+Rac1+and+Cdc42+signaling.">Amiloride inhibits macropinocytosis by lowering submembranous pH and preventing Rac1 and Cdc42 signaling.</a> Journal of Cell Biology. 188 (4), 547-563 (2010).</li><li>Fischer, E. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scanning+electron+microscopy.">Scanning electron microscopy.</a> Current Protocols in Microbiology. , (2012).</li><li>Yoshida, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dorsal+ruffles+enhance+activation+of+Akt+by+growth+factors.">Dorsal ruffles enhance activation of Akt by growth factors.</a> Journal of Cell Science. 131 (22), (2018).</li><li>Nakase, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Active+macropinocytosis+induction+by+stimulation+of+epidermal+growth+factor+receptor+and+oncogenic+Ras+expression+potentiates+cellular+uptake+efficacy+of+exosomes.">Active macropinocytosis induction by stimulation of epidermal growth factor receptor and oncogenic Ras expression potentiates cellular uptake efficacy of exosomes.</a> Science Reports. 5, 10300 (2015).</li><li>Gold, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+clathrin+independent+macropinocytosis-like+entry+mechanism+used+by+bluetongue+virus-1+during+infection+of+BHK+cells.">A clathrin independent macropinocytosis-like entry mechanism used by bluetongue virus-1 during infection of BHK cells.</a> PLoS One. 5 (6), 11360 (2010).</li><li>Mishra, R., Bhowmick, N. 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目前的SEM成像方案提供了一种工具，用于可视化和量化体 外细胞表面的膜褶皱形成，圆形突起和大毛细胞杯。虽然目前的方案侧重于巨噬细胞，但研究表明，膜褶皱的形成也发生在各种其他细胞类型上，包括树突状细胞，成纤维细胞，神经元和癌细胞11，12，14，21，30...

大毛细胞增多症是一种内吞过程，负责通过形成动态和肌动蛋白驱动的质膜突起（称为膜褶皱1）内化大量细胞外液及其含量。许多这些膜褶皱形成杯子，这些杯子关闭并融合回细胞上，并与质膜分离成大而异质的细胞内体，也称为大蛋白酶体1。虽然在多种细胞类型中，巨噬细胞增多症是由巨噬细胞集落刺激因子（M-CSF）和表皮生长因子（EGF）等生长因子诱导的，但在先天免疫细胞2，3，4，5，6，7，8中也观察到另一种独特的钙依赖性过程，称为组成性大羽细胞增多症。
细胞通过大羽核细胞增多症内化细胞外物质的能力已被证明在从营养吸收到病原体捕获和抗原呈递的各种生理过程中起重要作用9，10，11。然而，由于这一过程是非选择性和可诱导的，它也与许多病理条件有关。事实上，以前的研究表明，巨旋毛细胞增多症在阿尔茨海默病，帕金森病，癌症，肾结石和动脉粥样硬化中起重要作用12，13，14，15，16。此外，某些细菌和病毒已被证明利用大羽翼虫病进入宿主细胞并诱导感染17，18。有趣的是，巨旋细胞增多症的刺激也可用于在各种疾病条件下靶向递送治疗剂19，20。
以前的研究已经探索了大旋毛细胞增多症，方法是使用流式细胞术和共聚焦成像在不存在和存在抑制大羽细胞增多症的药理学药物的情况下定量内化荧光标记的液相标志物21，22。目前可用的抑制大旋毛细胞增多症的药理学工具仅限于并包括1）肌动蛋白聚合抑制剂（细胞查拉菌素D和latrunculins），2）PI3K阻滞剂（LY-290042和麦芽素）和3）钠氢交换剂（NHE）抑制剂（阿米洛利和EIPA）5，14，15，23，24，25.然而，由于这些抑制剂具有内吞作用的独立作用，因此很难选择性地确定大毛细胞增多对溶质摄取和疾病发病机制的贡献，特别是在 体内21中。
扫描电子显微镜（SEM）是一种电子显微镜，它使用聚焦的电子束26产生细胞的超高分辨率图像。在大毛细胞增多症研究中，SEM成像被认为是可视化质膜的形貌和形态特征，量化膜褶皱形成并研究其向大胰岛素体内化进展的金标准技术。此外，在存在和不存在大毛细胞增多症阻滞剂的情况下，扫描电子显微镜结合溶质摄取的定量，为体 外检查大羽细胞溶质内化提供了可靠的策略。本文提供了有关如何为SEM制备细胞，可视化细胞表面，量化褶皱形成以及检查其向杯封和大胰岛素体内化进展的详细方案。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.5% Trypsin-EDTA</td>
			<td>Gibco</td>
			<td>15400-054</td>
			<td></td>
		</tr>
		<tr>
			<td>2% Glutaraldehyde</td>
			<td>Electron Microscopy Sciences</td>
			<td>16320</td>
			<td></td>
		</tr>
		<tr>
			<td>4% Paraformaldehyde</td>
			<td>Santa Cruz Biotechnology</td>
			<td>281692</td>
			<td></td>
		</tr>
		<tr>
			<td>5-(N-ethyl-N-isopropyl)-Amiloride</td>
			<td>Sigma Life Science</td>
			<td>A3085</td>
			<td></td>
		</tr>
		<tr>
			<td colspan="2">Accuri C6 Flow Cytometer</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Carbon Adhesive Tabs</td>
			<td>Electron Microscopy Sciences</td>
			<td>77825-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl Sulfoxide</td>
			<td>Corning</td>
			<td>25-950-CQC</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s Modified Eagle Medium</td>
			<td>Cytiva Life Sciences</td>
			<td>SH30022.01</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon 24-well Clear Flat Bottom TC-treated Multiwell Cell Culture Plate</td>
			<td>Falcon</td>
			<td>353047</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>Gemini Bio</td>
			<td>900-108</td>
			<td></td>
		</tr>
		<tr>
			<td>FitC-dextran</td>
			<td>Thermo Fisher Scientific</td>
			<td>D1823</td>
			<td></td>
		</tr>
		<tr>
			<td>FM 4-64</td>
			<td>Thermo Fisher Scientific</td>
			<td>T13320</td>
			<td></td>
		</tr>
		<tr>
			<td>HERAcell 150i CO2 incubator</td>
			<td>Thermo Fisher Scientific</td>
			<td>51026282</td>
			<td></td>
		</tr>
		<tr>
			<td>Hummer Model 6.2 Sputter Coater</td>
			<td>Anatech USA</td>
			<td>58565</td>
			<td></td>
		</tr>
		<tr>
			<td colspan="2">JSM-IT500HR scanning electron microscope</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope Cover Glass</td>
			<td>Thermo Fisher Scientific</td>
			<td>12-545-82</td>
			<td></td>
		</tr>
		<tr>
			<td>Pen Strep</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr>
			<td>phorbol 12-myristate 13-acetate</td>
			<td>Millipore Sigma</td>
			<td>524400</td>
			<td></td>
		</tr>
		<tr>
			<td>RAW 264.7 macrophage</td>
			<td>ATCC</td>
			<td>ATCC TIB-71</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Human M-CSF</td>
			<td>Peprotech</td>
			<td>300-25</td>
			<td></td>
		</tr>
		<tr>
			<td>Samdri-790 Critical Point Dryer</td>
			<td>Tousimis Research Corporation</td>
			<td>8778B</td>
			<td></td>
		</tr>
		<tr>
			<td>SEM Aluminum Specimen Mounts</td>
			<td>Electron Microscopy Sciences</td>
			<td>75220</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Cacodylate</td>
			<td>Electron Microscopy Sciences</td>
			<td>12300</td>
			<td></td>
		</tr>
		<tr>
			<td>Texas red-dextra</td>
			<td>Thermo Fisher Scientific</td>
			<td>D1864</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue Solution</td>
			<td>Thermo Fisher Scientific</td>
			<td>15250061</td>
			<td></td>
		</tr>
		<tr>
			<td>Zeiss LSM 780 confocal microscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

visualizing membrane ruffle formation using scanning electron microscopy

膜褶皱是含有新聚合的肌动蛋白丝网状物的运动质膜突起的形成。膜褶皱可能自发形成或响应于生长因子、炎性细胞因子和磷脂醇酯。一些膜突起可能重组成圆形膜褶皱，在其远端边缘融合并形成杯子，这些杯子关闭并分离成称为大的异质液泡，称为大孔蛋白酶体。在此过程中，褶皱会捕获细胞外液和内化在大蛋白酶体内的溶质。高分辨率扫描电子显微镜（SEM）是一种常用的成像技术，用于可视化和量化细胞表面上的膜褶皱形成，圆形突起和封闭的大毛细胞杯。以下方案描述了细胞培养条件， 体外 膜褶皱形成的刺激，以及如何固定，脱水和制备用于使用SEM成像的细胞。该方法可以帮助回答有关大毛细胞增多症在生理和病理过程中的作用的关键问题，研究调节膜褶皱形成的新靶点，并鉴定尚未表征的生理刺激物以及巨棘球增多症的新型药理学抑制剂。

在这里，我们描述了所呈现技术的结果。 图1 所示的代表性SEM图像显示，在用PMA和M-CSF处理后，RAW 264.7巨噬细胞中形成膜褶皱。首先以3，500x的放大倍率捕获图像以进行定量，然后在更高的放大倍率（8，500x至16，000x）下捕获图像，以显示更详细的质膜。用大旋细胞增多症抑制剂EIPA预处理巨噬细胞减弱膜褶皱形成（图1）。与大毛细胞增多症相关的质膜?...

Watch this Scientific Journal Video about Visualizing Membrane Ruffle Formation using Scanning Electron Microscopy at JoVE.com

Visualizing Membrane Ruffle Formation using Scanning Electron Microscopy

大旋毛细胞增多症是一种高度保守的内吞作用过程，由形成富含F的片状膜突起（也称为膜褶皱）而引发。大旋细胞溶质内化速率增加与各种病理疾病有关。该协议提出了一种使用扫描电子显微镜 在体外 量化膜褶皱形成的方法。

使用扫描电子显微镜可视化膜褶皱形成

Membrane ruffling is the formation of motile plasma membrane protrusions containing a meshwork of newly polymerized actin filaments. Membrane ruffles may ...

目前的SEM成像方案提供了一种工具，用于可视化和量化体外细胞表面的膜褶皱形成，圆形突起和大毛细胞杯。SEM提供细胞表面的高分辨率图像，可用于可视化大旋毛细胞膜活动。该技术可用于发现调节大旋毛细胞增多症的新信号通路，并鉴定微旋细胞增多症的新型刺激物和抑制剂。首先使用高压灭菌镊子将无菌玻璃盖玻片放入24孔板的孔中。然后将264.7个巨噬细胞原生态以每毫升10个细胞的密度滑落到盖上，并将板在37摄氏度和5%二氧化碳的加湿培养箱中孵育过夜。第二天，用500微升新鲜完全培养基替换每个孔中的培养基，然后用载体对照（如DMSO）或大旋细胞增多症抑制剂（如EIPA）预处理巨噬细胞30分钟。接下来，为了促进膜的皱褶，用大旋多胞细胞增多刺激物（如一微摩尔PMA溶液或每毫升100纳克巨噬细胞集落刺激因子）处理细胞30分钟。为了固定细胞以进行扫描电子显微镜检查，从孔中吸出培养基并用冰冷的PBS洗涤盖玻片两次，然后将盖玻片在室温下在固定剂中孵育30分钟，然后在4摄氏度下孵育过夜。第二天，在不干扰细胞单层的情况下，轻轻洗涤，然后将盖玻片在500微升0.1-马达二甲酸钠中孵育15分钟。用500微升蒸馏水洗涤两次后，在500微升的分级乙醇系列中洗涤盖子滑两次，每次洗涤10分钟。要进行临界点干燥，请将盖玻片放入临界点干燥器中，并用100%乙醇覆盖。然后，按电源按钮并打开二氧化碳罐。按住冷却按钮约 30 秒钟，直到温度降至零摄氏度。然后，按下填充按钮，直到腔室窗口中出现气泡。接下来，按下吹扫按钮，直到吹扫废气中的乙醇气味消失。然后，再次按下冷却按钮，直到温度降至零摄氏度。重新按下完全和清除按钮以将其关闭。然后，关闭二氧化碳罐。重新按下冷却底部将其关闭，然后按加热按钮。将温度设置为42摄氏度，将压力设置为每平方英寸1， 200磅。压力和温度稳定后，按下排气按钮，使压力缓慢下降。一旦腔室压力达到每平方英寸150磅，按下通风口底部并等待，直到压力降至每平方英寸零磅。关闭临界点干燥器并取下盖玻片。接下来，使用碳粘合剂丝锥，将盖玻片安装在铝试样支架上进行扫描电子显微镜检查，然后在溅射镀膜机中使用金或钯进行溅射镀膜。打开溅射镀膜机的电源按钮。真空达到30毫托后，通过关闭气体开关并逆时针旋转细气阀来冲洗腔室以除去湿度和空气。一旦真空增加到200毫托，关闭气体开关，等到真空度达到30毫托。然后，再次冲洗腔室以除去湿度和空气，如图所示。冲洗腔室三次后，推动定时器底部并调节电压旋钮，直到仪表读数为10毫安。然后，从腔室中取出涂层盖玻片。要可视化和量化膜褶皱，请将样品盖插入扫描电子显微镜的腔室中，关闭门，然后按evac按钮。打开显微镜操作软件，将加速电压设置为15千伏，工作距离设置为10毫米。按坐标按钮并在控制器周围移动，直到单元格出现在观察屏幕的中心。将放大倍率设置为 3， 500 X，然后单击“照片”按钮对样品进行成像。这里显示的是具有代表性的扫描电子显微镜图像，显示了用PMA和巨噬细胞集落刺激因子处理后，原始264.7巨噬细胞中膜褶皱形成。用大毛细胞增多症抑制剂EIPA预处理巨噬细胞可减弱膜褶皱的形成。在褶皱形成过程中，质膜经历不同的形态阶段，包括片状膜突起，C形膜褶皱和大毛细胞杯。PMA和巨噬细胞集落刺激因子治疗后的膜褶皱形成可以使用扫描电子显微镜进行定量，而大核苷酸体的形成可以通过替代成像技术来确认，例如使用德克萨斯红葡聚糖和FM4-64的共聚焦显微镜。蓝色箭头表示膜破裂，而黄色和绿色箭头指向微胰岛素样体。最后，可以使用荧光液相标记物（如FITC或德克萨斯红葡聚糖）通过流式细胞术来确认和量化大旋胞子细胞增多症。除SEM外，还可以进行荧光标记葡聚糖内化的活细胞成像和流式细胞术分析，以研究和量化大旋细胞增多症。

Research

JoVE Journal

Medicine

Oral Biofilm Analysis of Palatal Expanders by Fluorescence In-Situ Hybridization and Confocal Laser Scanning Microscopy

腭扩展口腔生物膜分析，荧光原位杂交和激光共聚焦显微镜

Confocal laser scanning microscopy (CLSM) of natural heterogeneous biofilm is today facilitated by a comprehensive range of staining techniques, one of ...

科研

医学

Quantifying Glomerular Permeability of Fluorescent Macromolecules Using 2-Photon Microscopy in Munich Wistar Rats

利用双光子显微镜在慕尼黑Wistar大鼠量化肾小球通透性荧光大分子

Kidney  diseases involving urinary loss of large essential macromolecules, such as  serum albumin, have long been thought to be caused by alterations in ...

Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells

人类前列腺上皮细胞形成的使用鼠类泌尿生殖窦间质细胞和人类干细胞的组织重组

Progress in prostate cancer research is severely  limited by the availability of human-derived and hormone-na&iuml;ve model systems,  which limit our ...

Using a Laminating Technique to Perform Confocal Microscopy of the Human Sclera

使用层压技术来执行人类巩膜共聚焦显微镜


The sclera is a dense connective tissue that covers and protects the eye. It mainly consists of dense collagen bundles (types I, III, IV, V, VI, and ...

Quantitative Visualization of Leukocyte Infiltrate in a Murine Model of Fulminant Myocarditis by Light Sheet Microscopy

通过轻型显微镜对小鼠急性心肌炎模型中白细胞浸润的定量可视化

Light-sheet fluorescence microscopy (LSFM), in combination with chemical clearing protocols, has become the gold standard for analyzing fluorescently ...

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

制备和<em&gt;体外</em&gt;磁化的表征的miR-改性内皮细胞

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene ...

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation

血管性血友病因子-血小板串形成的流室模型研究血管血友病因子的病理生理学

Von Willebrand factor (VWF) is a multimeric glycoprotein coagulation factor that mediates platelet adhesion and aggregation at sites of endothelial damage ...

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts

扫描骨骼遗骸的骨骼矿物密度在法医学背景下

The purpose of this paper is to introduce a promising, novel method to aid in the assessment of bone quality in forensically relevant skeletal remains. ...

Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants

环境毒物暴露大鼠下颌切牙釉质器官的显微解剖

Enamel defects resulting from environmental conditions and ways of life are public health concerns because of their high prevalence. These defects result ...

Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery

经食管超声心动图在心脏手术中无创地测定涡旋形成时间

Trans-mitral blood flow produces a three-dimensional rotational body of fluid, known as a vortex ring, that enhances the efficiency of left ventricular ...