物理與生命系統間的思考 詹明宜 物理所生物物理研究室
生命是甚麼 ? A. 神創造的 B. 物質所構造的複雜系統 C. 複雜訊息系統 D. 空 E. 以上皆是
物理 v.s. 生命系統 物理 Physical science: branches of science such as physics, chemistry and geology that are concerned with things that do not have life.. 生命系統 ? Life or Living: the person or animal that is alive. Alive: they have life.
植物人 在國際醫學界通行的定義是 “ 持續性植物狀態 ( persistent vegetative status ) ” ,簡稱 PVS 。所謂植 物生存狀態常常是因顱腦外傷或其他原因,如溺水、 中風、窒息等大腦缺血缺氧、神經元退行性改變等導 致的長期意識障礙,表現為病人對環境毫無反應,完 全喪失對自身和周圍的認知能力﹔病人雖能吞咽食物、 入睡和覺醒,但無黑夜白天之分,不能隨意移動肢體, 完全失去生活自理能力﹔能保留軀體生存的基本功能, 如新陳代謝、生長發育。
腦死 腦死 : “ 腦死亡 ” 病人是永遠不可能存活的,其主要特征 是自主呼吸停止、腦干反射消失。而 PVS 患者有自主 呼吸,脈搏、血壓、體溫可以正常,但無任何言語、 意識、思維能力。他們的這種 “ 植物狀態 ” ,其實是一 種特殊的昏迷狀態。因病人有時能睜眼環視,貌似清 醒,故又有 “ 清醒昏迷 ” 之稱。
死亡 中止所有生理功能,包括循環系統、腦 神經系統等等。且這些生理功能的中止 是不可逆的。
生命系統 生態系統 個體 ( 人 ) 功能系統 ( 感覺, 循環 … ) 器官 ( 耳朵 ) 組織 ( 骨頭, 韌帶 ) 細胞 ( 頭髮細胞 ) 胞器
「葉克膜」葉醫師 「葉克膜體外循環機」 這套機器能取代心肺功 能利用體外循環輔助昏 迷病患,維持血液循環。 在邵曉鈴發生車禍後, 葉克膜體外循環機適時 發揮功能,成功救活邵 曉鈴,民眾就誤以為簡 稱「葉克膜」的就是邵 曉鈴急救團隊中的一員。
卡拉 OK 大賽
第一首歌第一首歌演唱者 A. 楊宗緯 B. 林宥嘉 C. 周杰倫 D. 陶詰 E. 曾玠郡
第二首歌第二首歌演唱者 A. 齊豫 B. 張艾嘉 C. 黃鶯鶯 D. 蔡琴 E. 潘越雲
第三首歌第三首歌演唱者 A. The Beatles B. ABBA C. Pink Floyd
Pink Floid: The Wall … 年 8 月 15 日開始建 築 封鎖東西德 交往 1989 年 11 月 11 日,柏林 圍牆正式開 始拆毀
為甚麼我們可以聽見聲音 ?
Sound- vibrations of the molecules in a medium like air. The hearing spectrum for humans is approximately between 20 to 20,000 Hz. Wavelength: 1700cm~1.7cm Wave propagation
耳朵
物理的特性 生理功能及解剖特性 病理 : 趨向於違反生理功能及解剖特性
波的疊加原理 (Superposition Principle) 當幾列波在介質中某 點相遇時, 該點的振 動位移是各列波單獨 存在時在該點引起的 位移的疊加
波的疊加原理 (Superposition Principle) 駐波 (standing waves) 拍 (beats)
Cochlea from a human fetus
Pitch Perception 1.Frequency Theory: basilar membrane vibrates in synchrony with the sound source & causes action potentials to occur at about the same frequency. ( a 100 Hz tone, would have 100 action potentials per second in the auditory nerve) Pro: good for low frequencies Con: bad for high frequencies,
Pitch Perception 2. Place Theory: basilar membrane is tuned to specific frequencies at different locations on the membrane & vibrates whenever that frequency is present. Pro: good for high frequencies Con: bad for low frequencies
Pitch Perception Volley theory- Neurons may fire in different phases (time-locked) that when taken together may code the pitch. If all of these neuron fibers are taken together they may produce a volley of impulses by various fibers that as a whole code the pitch. The volley theory seems to work for tones up 5000 Hz.
Summary of theories 1. Low Frequencies are coded by frequency of nerve impulses (up to 50 Hz). 2. High frequencies are coded in terms of the place along the basilar membrane which shows the greatest activity. (over 5000 Hz) 3. For intermediate frequencies (from 60 to 5000 Hz) pitch is coded through a combination of Volley & place.
心血管的一些物理思考
血壓分配
心血管系統像亞瑪遜河 ?
蜿蜒而流 細細綿長
還是比較像一個輸配電系統
電線到那兒 開關就有電 ?
心血管像河流般流動 如果以動量為傳輸之原動力,則血管之分 支不宜有突然之彎曲。 循環系統最好像一顆倒置的樹一樣,而心 臟在樹根的位置,而且樹枝與樹幹間的相關位 置不可移動。
流量理論 : (1) 為何有心舒壓 ? 為了流量之增大,主動脈之心舒壓應為 負值最好,而所有脊椎哺乳動物之心舒 壓皆為正 80 mmHg 左右。
流量理論 : (2) 為何心跳為固定速率 ? : 以流量之觀點,有動量既可。心跳率 依生理代謝多寡變動,心跳不必固定速 率。
流量理論 : (3) 主昇動脈為何轉彎 180 °? : 心臟打出為衝量,經過 180 ° 轉彎則動 量完全消耗。在左心室中, 心臟由肌 肉收縮將血液變成衝量射出。但轉彎 180 ° 以後只有 2% 呈動能形態。
流量理論 : (4) 為何血管流入器官呈 90°? : 90° 是將動量完全無分量之角度。但 腎動脈、脾動脈、氣管動脈、胸動脈 等進入器官之動脈皆與主動脈呈 90° ,表示進入器官之血液,不是以動量 為動力。生理上希望將動量之影響降 到最低。
流量理論 : (5) 為何大動物心跳慢, 小動物心跳反快 ? : 大動物所送血量較大,流量大,則 心跳應較快,小動物體積小,所送血 量亦少,心跳應較慢,更何況與 ( 體 積 ) 1/3 成反比要如何解釋 ?
流量理論 : (6) 動物如何運動 ? : 這是一個極大的問題。動物都有循環 系統。如果輸送血流靠動量, " 動量為 向量 " ,我們一舉手,一投足都會嚴重 妨害血液的循環。我們應是不能動的植 物才行。
氣的樂章
A historical review of the sphygmomanometers
你有高血壓嗎 ?
The consideration of blood circulation in modern medicine The ancient Greek physician Galen (130~200AD) first proposed the existence of blood in the human body the heart constantly produced blood Until 1616 when William Harvey (1578~1657) announced that Galen was wrong proposed that there was a finite amount of blood that circulated the body in one direction only.
The first invasive blood pressure measurement (1733) The first recorded instance of the measurement of blood pressure was in 1733 by the Reverend Stephen Hales AD. 1677~1761 A British Veterinarian Fellow of Royal Society
Hales ’ s first invasive blood pressure measurement Fifteen years beforehand, he took a horse and inserted a brass pipe into an artery. This brass pipe was connected to a glass tube. Hales observed the blood in the pipe rising and concluded that this must be due to a pressure in the blood. At this time the technique was invasive and highly inappropriate for clinical use.
The first Physician-Physicist (1828) Poiseuille (1799~1869) Qualified as a doctor (1828) Won a medal on the use of a mercury manometer for the measurement of arterial blood pressure (1828) Connect the manometer to a cannula was inserted into arteries that is as small as 2mm in diameter
Ludwig ’ s invasive Kymograph (1847) Until 1847 that human blood pressure was recorded by Carl Ludwig's kymograph with catheters inserted directly into the artery. Ludwig's kymograph consisted of a U-shaped manometer tube connected to a brass pipe cannula into the artery. The manometer tube had an ivory float onto which a rod with a quill was attached. This quill would sketch onto a rotating drum hence the name 'kymograph', 'wave writer' in Greek. However blood pressure could still only be measured by invasive means.
Karl ’ s conceptual non-invasive Sphygmomanometer (1855) Karl Vierordt, found in 1855 that with enough pressure, the arterial pulse could be obliterated. Vierordt used an inflatable cuff around the arm to constrict the artery.
Etienne Jules Marey ’ s sphygmomanometer (1860) applied Vierordt's principle of applying counter pressure to overcome the arterial pressure the arm was enclosed in a glass chamber filled with water, which was connected both to a sphygmograph and to a kymograph
Samuel Siegfried Karl Ritter von Basch ’ s sphygmomanometer (1881) consisted of a water-filled bag connected to a manometer. The manometer was used to determine the pressure required to obliterate the arterial pulse. Direct measurement of blood pressure by catheterisation confirmed that von Basch's design would allow a non- invasive method to measure blood pressure. Feeling for the pulse on the skin above the artery, was used to determine when the arterial pulse disappeared.
Development of Present-day Technique: the Ideas of an Italian Doctor Riva-Rocci (1896) Ease of application, rapidity in action, precision, harmlessness to patient Apply a cuff, a rubber bag, surround the circumference of the arm to press the brachial artery and was increased until the radial pulse could no longer be palpated. The pressure in the cuff was registered by the usual mercury manometer the reading at which the pulse reappeared was taken as the systolic blood pressure.
Placing a stethoscope over the brachial artery (1905) In 1905 N C Korotkoff, a Russian surgeon, reported that by placing a stethoscope over the brachial artery at the cubital fossa, Distal to the Riva-Rocci cuff, tapping sounds could beheard as the cuff was deflated, caused by blood flowing back into the artery.
Current blood pressure measurement
K-sound and the oscillometry NIBP
EN standards in sphygmomanometers EN :1995 Non-invasive sphygmomanometers - Part 1: General requirements EN :1995/A1:2002 EN :1995 Non-invasive sphygmomanometers - Part 2: Supplementary requirements for mechanical sphygmomanometers EN :1997 Non-invasive sphygmomanometers - Part 3: Supplementary requirements for electro- mechanical blood pressure measuring systems EN :1997/A1:2005 EN :2004 Non-invasive sphygmomanometers - Part 4: Test procedures to determine the overall system accuracy of automated non-invasive sphygmomanometers
Medical device regulations US (FDA: 510(k), PMA, IDE, QSR) CE (MDD, IVD, AIMD) Japan (MHLW, 厚生省, PMDA) Canada (CAMCAS) China (SFDA) Australia (TGA) GHTF