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<p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">什么是超声波？</span></strong></span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">大家知道人耳能听到的声音频率为</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">20Hz----20KHz</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，低于</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">20Hz</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">的声波为次声波，人耳是听不到的，高于</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">20KHz</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">的声波为超声波，人耳也是听不见的。</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超声波之所以被广泛用于医疗领域是因为他有许多奇妙的特点：</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">1.</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">由于<span style="max-width: 100%; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;">超声波频率高、波长短</span></span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，他可以像光那样沿直线传播，使得我们有可能向某已确定方向上发射超声波，</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">2.</span><span style="max-width: 100%; font-family: 宋体; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;">声波是纵波</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，可以顺利地在人体组织里传播。</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">3.</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超声波遇到不同的介质交接面时会<span style="max-width: 100%; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;">产生反射波</span></span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，这些特点构成了今天超声仪器在医学领域广泛应用的基础。</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"><br style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;" /></span></p><p style="text-align:center"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"><img data-s="300,640" data-type="jpeg" src="http://mmbiz.qpic.cn/mmbiz/dx3KibwtDhvfic2t9odHbMaSr6GIAvqhqvbbRBoNAbFclLWjxUibJC55mxSmvTlMlLmKKXZIGyFdJMic07QItP0qMQ/0?wx_fmt=jpeg" data-ratio="0.8156996587030717" data-w="293" /><br /></span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超成像的<span style="max-width: 100%; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">基本原理</strong></span>就是：向人体发射一组超声波</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">按一定的方向进行扫描。根据监测其回声的延迟时间</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">强弱就可以判断脏器的距离及性质。经过电子电路和计算机的处理</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">形成了我们今天的</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超图像。</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超的关键部件就是我们所说的超声探头</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">(probe)</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">其内部有一组超声换能器</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">是由一组具有压电效应的特殊晶体制成。这种压电晶体具有特殊的性质</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">就是在晶体特定方向上加上电压</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">晶体会发生形变</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">反过来当晶体发生形变时</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">对应方向上就会产生电压</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">实现了电信号与超声波的转换。</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"><br style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;" /></span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> 一般的</span><span style="max-width: 100%; color: rgb(0, 128, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超工作过程</span></strong></span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">为：当探头获得激励脉冲后发射超声波，（同时探头受聚焦延迟电路控制，实现声波的声学聚焦。）然后经过一段时间延迟后再由探头接受反射回的回声信号，探头接收回来的回声信号经过滤波，对数放大等信号处理。然后由</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">DSC</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">电路进行数字变换形成数字信号，在</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">CPU</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">控制下进一步进行图像处理，再同图表形成电路和测量电路一起合成视频信号送给显示器形成我们所熟悉的</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超图像，也称二维黑白超声图像。</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">以上我们谈到了黑白</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">再让我们谈谈彩色</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">即</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">“</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">彩超</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">”</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">。其实彩超并不是看到了人体组织的真正的颜色</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">而是在黑白</span><span style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">B</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">超图像基础上加上以多普勒效应原理为基础的伪彩而形成的。那么何谓多普勒效应呢</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">当我们站在火车站台上听有远处开来的火车笛叫声会比远离我们的火车笛叫声音调要高</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">也就是说对于静止的观测者来说</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">向着观测者运动物体发出的声波频率会升高</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">相反频率会降低</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">这就是著名的多普勒效应。现代医用超声就是利用了这一效应</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">当超声波碰到流向远离探头液体时回声频率会降低</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">流向探头的液体会使探头接收的回声信号频率升高。利用计算机伪彩技术加以描述</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">使我们能判定超声图像中流动液体的方向及流速的大小和性质</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">并将此叠加在二维黑白超声图像上</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">，</span><span style="max-width: 100%; font-family: 宋体; box-sizing: border-box !important; word-wrap: break-word !important;">形成了我们今天见到的彩超图像。</span></p><p><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 25.6px; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-family: Arial, Verdana, sans-serif; font-size: 14px; line-height: 24px; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(249, 249, 249);">广州市设备维修有限公司</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">地址：广州市天河区银利街银利茶叶博览中心E栋4楼E4030室 邮编：510507</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">电话：(+86)020-8722 8723 8764 5360 8764 2943 传真：020-8722 8623</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">全国统一免费服务热线：400-020-6788</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">微信公众帐号：</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><img data-ratio="1" data-type="jpeg" data-w="120" width="auto" src="http://mmbiz.qpic.cn/mmbiz/dx3KibwtDhvfCZvZq5PcthnDKlnnq3AalhbichW77J3B70osicTickklZybNKUZqc44DZ0oaWaHm2p0TaA9478icwPg/640?wx_fmt=jpeg" style="box-sizing: border-box !important; word-wrap: break-word !important; width: auto !important; visibility: visible !important;" /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">维修咨询：QQ: 712638 404</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">设备咨询: QQ: 712638 405</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">软件咨询：QQ: 712638 406</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">配件咨询：QQ: 712638 407</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">交流Q群：1106 11074</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">网址：http://www.yiliaoshebeiweixiu.com</span></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; line-height: 24px; font-family: Arial, Verdana, sans-serif; box-sizing: border-box !important; word-wrap: break-word !important; background-color: rgb(255, 255, 255);"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">电子邮箱：service@yiliaoshebeiweixiu.com</span></p><p><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;"><br /></span></p><p><br /></p>
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发表于 2020-10-19 23:54:21