醫(yī)學(xué)電子儀器wiederholen課件

1、1Chapter 1Basic Concepts of Medical Instrumentation 1Chapter 1UnstableProbability NonlinearityCharacteristics of physiological signalHuman Body SystemCharacteristics of physiologic Bioelectrical SignalsCharacteristics of Biomedical Measurement Bioelectrical SignalsCharacteMulti-variability生命體的生命活動(dòng)是由

2、多個(gè)生理及生化參量共同決定的，而在測(cè)量過(guò)程中，往往只針對(duì)某種效應(yīng)和某些參量進(jìn)行測(cè)量。生命系統(tǒng)的這種多變量特性，決定了測(cè)量方法和技術(shù)以及測(cè)量結(jié)果的涵義和結(jié)論都會(huì)帶有明顯的局限性。Characteristics of Biomedical MeasurementMulti-variabilityCharacteristiDisturbance 生物醫(yī)學(xué)測(cè)量過(guò)程中，由于被測(cè)參數(shù)往往十分微弱，易受外界環(huán)境干擾(例如工頻交流電干擾)和來(lái)自人體自身的其他無(wú)用信息的干擾(例如在測(cè)量體表希氏束電位時(shí)，很易受來(lái)自肌電信號(hào)的干擾)，人體活動(dòng)時(shí)的體位變化、電極不良及傳感器錯(cuò)位時(shí)也會(huì)產(chǎn)生偽差，必須采用抗干擾技術(shù)、排除

3、偽差等方法提取有用信號(hào)。Characteristics of Biomedical MeasurementDisturbanceCharacteristics of Psychophysiology Factors 在測(cè)量過(guò)程中，由于被測(cè)對(duì)象出現(xiàn)緊張，生理和心理都會(huì)發(fā)生變化。心理的變化會(huì)導(dǎo)致生理參數(shù)(心率、血壓、體溫等)變化。在測(cè)量過(guò)程中，被測(cè)者的不理解和不配合，尤其在進(jìn)行麻醉和經(jīng)受物理和藥物刺激時(shí)，受試者不能很好配合，直接影響測(cè)量過(guò)程中的偽差，從而影響測(cè)量的準(zhǔn)確度Characteristics of Biomedical MeasurementPsychophysiology Factors

4、CharacClose Loop 生命體具有精確的自動(dòng)調(diào)節(jié)功能，這是由于在生命體中存在多環(huán)路、多層次、多重控制的閉環(huán)系統(tǒng)特性所決定的。多種原因可導(dǎo)致同一生理參數(shù)的變化，同一原因又可導(dǎo)致多種生理參數(shù)的同時(shí)變化。因此，測(cè)量單一生理參數(shù)難于有效評(píng)估生理和病理狀態(tài)，需要多參數(shù)綜合測(cè)試，并用適當(dāng)方法使人體的閉環(huán)系統(tǒng)暫時(shí)開(kāi)環(huán)，以測(cè)量某一環(huán)節(jié)的開(kāi)環(huán)響應(yīng)特性，正確地加以定位并確保測(cè)量結(jié)果的唯一性與正確性。Characteristics of Biomedical MeasurementClose Loop Characteristics of Safety生物醫(yī)學(xué)測(cè)量的對(duì)象是生命體，尤其是人體，因此安全性極其

5、重要。1）測(cè)量中應(yīng)防止各種電擊的危害尤其是在體內(nèi)對(duì)心臟進(jìn)行直接測(cè)量時(shí)，極微小的電流(uA級(jí))也有可能導(dǎo)致室顫（Vantricular Fibrillation）。其次，電流通過(guò)人體時(shí)，會(huì)產(chǎn)生許多物理變化(例如熱效應(yīng))和化學(xué)變化，并會(huì)引起多種復(fù)雜的生理效應(yīng)。2）測(cè)量裝置不能產(chǎn)生有毒物質(zhì)，應(yīng)與組織與血液有較好的生物相容性(Bio-compatibility )。Characteristics of Biomedical MeasurementSafetyCharacteristics of BiomEvaluation 生物醫(yī)學(xué)測(cè)量的新方法，尤其是一些間接測(cè)量方法往往會(huì)涉及測(cè)試模型的建立問(wèn)題。由于

6、研究者對(duì)生命現(xiàn)象復(fù)雜程度了解不夠，加上生物個(gè)體差異很大，因此測(cè)試模型往往帶有片面性，在評(píng)估時(shí)也缺乏正確、有效的措施。Characteristics of Biomedical MeasurementEvaluation Characteristics ofEnvironment 測(cè)量環(huán)境，例如溫度、濕度、電磁場(chǎng)干擾、振動(dòng)、沖擊等，都會(huì)使測(cè)量產(chǎn)生困難。尤其是在進(jìn)行細(xì)胞級(jí)的測(cè)量時(shí)，利用微電極測(cè)量細(xì)胞內(nèi)的電位變化時(shí)，對(duì)環(huán)境要求很?chē)?yán)，否則將影響測(cè)量結(jié)果的可靠性。Characteristics of Biomedical MeasurementEnvironment Characteristics of

7、a priori knowledge由于研究者、設(shè)計(jì)者乃至操作者缺乏對(duì)生物醫(yī)學(xué)的先驗(yàn)知識(shí)，可能對(duì)生物醫(yī)學(xué)測(cè)量的結(jié)果以及表達(dá)產(chǎn)生影響。在臨床診斷過(guò)程中，醫(yī)生必須利用其對(duì)醫(yī)學(xué)的先驗(yàn)知識(shí)結(jié)合儀器測(cè)量的結(jié)果進(jìn)行綜合判斷。Characteristics of Biomedical Measurementa priori knowledgeCharacteristSuitability 任何測(cè)量方法與技術(shù)都有一定的局限性，尤其是在生物醫(yī)學(xué)領(lǐng)域。生命體中的各個(gè)系統(tǒng)、組織和器官，同一測(cè)量對(duì)象可能有多種測(cè)量方法，每一種測(cè)量都在一定條件限制下進(jìn)行的。因此，不同測(cè)量對(duì)象需要有其相關(guān)的測(cè)量手段與方法，在進(jìn)行測(cè)量以前首

8、先要研究方法與技術(shù)的適用性問(wèn)題Characteristics of Biomedical MeasurementSuitability Characteristics ofBiopotentialPressureFlowDimensions (imaging)Displacement (velocity, acceleration, force)ImpedanceTemperatureChemical ConcentrationMeasurand: The physical quantity, property, or condition Generalized instrumentation

9、 system BiopotentialMeasurand: The phyMedical and Physiological Parameters Generalized instrumentation system Medical and Physiological ParaSensor and TransducerSensorConverts a physical measurand to an electrical outputInterface with living systemMinimize the energy extractedMinimally invasivediaph

10、ragmStrain gagepressuredisplacementelectric voltage Generalized instrumentation system Sensor and TransducerSensordiaSignal ConditioningAmplificationFilteringImpedance matchingAnalog/Digital for signal processingSignal form (time and frequency domains) Generalized instrumentation system Signal Condi

11、tioningAmplificatiOutput DisplayNumerical or graphicalDiscrete or continuousPermanent or temporaryVisual sense Auditory sense (Doppler ultrasonic signals) Generalized instrumentation system Output DisplayNumerical or graParameters used to evaluate medical instrument:Accuracy: The difference between

12、the true value and the measured value divided by the true valuePrecision: The number of distinguishable alternatives from which a given results is selected Resolution: The smallest increment quantity that can be measured with certaintyReproducibility: The ability to give the same output for equal in

13、puts applied over some period of time.Generalized Static CharacteristicsParameters used to evaluate meHigh precision Low accuracyHigh accuracy Low precisionGeneralized Static CharacteristicsHigh precision Low accuracyHigGeneralized Static CharacteristicsGeneralized Static Characteris醫(yī)學(xué)電子儀器Chapter 2-

14、Basic Sensors and Principles醫(yī)學(xué)電子儀器The term transducer is defined as a device that converts one form of energy to another. A sensor converts a physical measurand to an electric output.傳感器的定義：能感受或響應(yīng)規(guī)定的被測(cè)量并按照一定的規(guī)律轉(zhuǎn)換成可用輸出信號(hào)的器件或裝置。傳感器的定義和組成醫(yī)用傳感器（medical sensor ）：能夠感知多數(shù)為非電量的生物信息并將其轉(zhuǎn)換成電學(xué)量的器件或裝置。The term tr

15、ansducer is defined傳感器起著關(guān)鍵作用，其原因：生物信號(hào)很多是非電量信號(hào)，必須經(jīng)過(guò)傳感器感知才能轉(zhuǎn)換成電信號(hào)生物信號(hào)十分微弱生物信號(hào)信噪比很低生物信號(hào)多數(shù)變化頻率很低，容易受到50Hz電源和其他生理活動(dòng)的干擾無(wú)創(chuàng)傷的檢測(cè)，患者才樂(lè)于接受傳感器的作用傳感器決定著檢測(cè)的可能性和檢測(cè)儀器的精確性、可靠性及其應(yīng)用范圍。傳感器起著關(guān)鍵作用，其原因：傳感器的作用傳感器決定著檢測(cè)的可(1)足夠高的靈敏度，能夠檢測(cè)出微弱的生物信號(hào)。(2)盡可能高的信噪比，以便在干擾和噪聲背景中提取有用的信息。(3)良好的精確性，以保證檢測(cè)出的信息準(zhǔn)確、可靠。(4)足夠快的響應(yīng)速度，能夠跟隨生物體信息量的變化

16、(5)良好的穩(wěn)定性，保持長(zhǎng)時(shí)間檢測(cè)漂移很小，輸出穩(wěn)定。(6)較好的互換性，調(diào)試、維修方便。醫(yī)用傳感器的特性和要求醫(yī)用傳感器的特性(1)足夠高的靈敏度，能夠檢測(cè)出微弱的生物信號(hào)。醫(yī)用傳感器的(1)與人體接觸、特別是植入體內(nèi)的傳感器材料必須是無(wú)毒的，并且與生物體組織具有良好的相容性，長(zhǎng)期接觸不會(huì)引起排異、炎癥等不良反應(yīng)。(2)傳感器在進(jìn)行檢測(cè)時(shí)，不能影響或者盡可能少影響正常的生理活動(dòng)，否則檢測(cè)的信息將是不準(zhǔn)確的。(3)傳感器應(yīng)具有良好的電氣安全性，特別是與體內(nèi)接觸的傳感器應(yīng)按照防止微電擊的電氣安全標(biāo)準(zhǔn)具有良好的絕緣性能。(4)傳感器在結(jié)構(gòu)上和性能上要便于清潔和消毒，防止有害物質(zhì)交叉感染。 醫(yī)用傳感

17、器的特殊要求醫(yī)用傳感器的特性和要求(1)與人體接觸、特別是植入體內(nèi)的傳感器材料必須是無(wú)毒的，并Wheatstone Bridgevo is zero when the bridge is balanced- that is when If all resistor has initial value R0 then if R1 and R3 increase by R, and R2 and R4 decreases by R, then Wheatstone Bridgevo is zero w27Piezoelectric effect1、正（順）壓電效應(yīng)2、逆壓電效應(yīng)（電致伸縮）壓電介質(zhì)

18、正壓電效應(yīng)Q(E) 電能T(S) 機(jī)械能逆壓電效應(yīng)27Piezoelectric effect1、正（順）壓電28居里點(diǎn)573，六角晶系結(jié)構(gòu)光軸電軸機(jī)械軸Piezoelectric MaterialsQuartz Crystal 軸（光軸）： 軸（電軸） ：軸（機(jī)械軸） ：光線沿此方向入射時(shí)不產(chǎn)生雙折射現(xiàn)象，沿此方向加力也不產(chǎn)生壓電電荷產(chǎn)生壓電電荷的方向 沿此方向受力時(shí)變形最小，機(jī)械強(qiáng)度最大28居里點(diǎn)573，六角晶系結(jié)構(gòu)光軸電軸機(jī)械軸PiezoelVoTo find Vo, assume system acts like a capacitor (with infinite leak resi

19、stance):Capacitor:(typically pC/N, a material property)k for Quartz = 2.3 pC/Nk for barium titanate = 140 pC/NPiezoelectric effectVoTo find Vo, assume system acView piezoelectric crystal as a charge generator:Rs: sensor leakage resistanceCs: sensor capacitanceCc: cable capacitanceCa: amplifier input

20、 capacitanceRa: amplifier input resistanceRaTransfer Function of Piezoelectric SensorsView piezoelectric crystal as Convert charge generator to current generator:CurrentRaTransfer Function of Piezoelectric SensorsKs = K/C, sensitivity, V/m = RC, time constantRaConvert charge generator to cu醫(yī)學(xué)儀器Chapt

21、er 4- The Origin of Biopotentials醫(yī)學(xué)儀器動(dòng)作電位的概念:指可興奮細(xì)胞在受到一定強(qiáng)度的刺激后，膜兩側(cè)的電位在原有靜息電位的基礎(chǔ)上發(fā)生的一次快速的倒轉(zhuǎn)和復(fù)原The Active State動(dòng)作電位的概念:指可興奮細(xì)胞在受到一定強(qiáng)度的刺激后，膜兩側(cè)的動(dòng)作電位有一下幾部分組成:上升支下降支超射 負(fù)后電位正后電位The Active State動(dòng)作電位有一下幾部分組成:The Active StateThe Active State不同種類細(xì)胞的動(dòng)作電位其特征相似，但其變化幅度與持續(xù)時(shí)間是有差別的。在骨骼肌和粗神經(jīng)纖維鋒電位的幅值可達(dá)120mV,持續(xù)時(shí)間為0.52.0m

22、s，而后電位則易變性較大，負(fù)后電位一般約持續(xù)530ms，正后電位持續(xù)6080ms。The Active State不同種類細(xì)胞的動(dòng)作電位其特征If stimulus depolarize the cell such that Vcell Vthreshold an action potential is generated. Internal mediaExternal media+-+Electric FieldNa+140 mmol/liter of K+2.5 mmol/liter of K+-+Electric FieldK+The Active StateIf stimulus de

23、polarize the celAction PotentialAbsolute refractory period: membrane can not respond to any stimulus.Relative refractory period: membrane can respond to intense superthreshold stimulus.Action PotentialAbsolute refraAction PotentialAction Potential1.電化學(xué)驅(qū)動(dòng)力：決定離子跨膜流動(dòng)的方向和速度，某離子電化學(xué)驅(qū)動(dòng)力應(yīng)等于膜電位與該離子平衡電位之差。如Na

24、+ ：Em-ENa=-70mV-(+60mV)=-130mVAP產(chǎn)生的基本條件:膜內(nèi)外存在Na+差: Na+iNa+O 110；膜在受到閾刺激而興奮時(shí)，對(duì)離子的通透性增加： 即電壓門(mén)控性Na+、K+通道激活而開(kāi)放。Mechanism of AP1.電化學(xué)驅(qū)動(dòng)力：Mechanism of AP當(dāng)細(xì)胞受到刺激細(xì)胞膜上少量Na+通道激活而開(kāi)放Na+順濃度差少量?jī)?nèi)流膜內(nèi)外電位差局部電位當(dāng)膜內(nèi)電位變化到閾電位時(shí)Na通道大量開(kāi)放Na+順電化學(xué)差和膜內(nèi)負(fù)電位的吸引再生式內(nèi)流膜內(nèi)負(fù)電位減小到零并變?yōu)檎娢唬ˋP上升支）Na+通道關(guān)Na+內(nèi)流停+同時(shí)K+通道激活而開(kāi)放K順濃度差和膜內(nèi)正電位的吸引K迅速外流膜內(nèi)電

25、位迅速下降，恢復(fù)到RP水平（AP下降支） Na+i、K+O激活Na+K+泵Na+泵出、K+泵回，離子恢復(fù)到興奮前水平后電位Mechanism of AP當(dāng)細(xì)胞受到刺激細(xì)胞膜上少量Na+通道激活而開(kāi)放Na+順濃度差Mechanism of APMechanism of AP結(jié)論：1、AP的上升支由Na內(nèi)流形成，下降支是K外流形成的，后電位是NaK泵活動(dòng)引起的2、AP的產(chǎn)生是不消耗能量的，AP的恢復(fù)是消耗能量的（NaK泵的活動(dòng)）。3、AP = Na的平衡電位。 Mechanism of AP結(jié)論：Mechanism of APAction Potential TravelAction Potent

26、ial Travel心肌細(xì)胞的分類工作心肌細(xì)胞 (working cardiac cell)： 心房肌、心室肌自律心肌細(xì)胞 (rhythmic cell):特殊分化的心肌細(xì)胞，包括竇房結(jié)、房室交界區(qū)、房室束和浦肯野纖維等?；静缓≡w維，無(wú)收縮性；具有自律性和特殊傳導(dǎo)性；構(gòu)成了心臟的起搏傳導(dǎo)系統(tǒng)。Cardiac conduction system心肌細(xì)胞的分類特殊分化的心肌細(xì)胞，包括竇房結(jié)、房室交界區(qū)、房Rhythmic cell and Contractile cellRhythmic cell and Contractile 1. 傳導(dǎo)途徑 竇房結(jié) 結(jié)間束 房間束（優(yōu)勢(shì)傳導(dǎo)通路） 房室交

27、界 心房肌 房室束 左、右束支 浦肯野纖維 心室肌Cardiac conduction system1. 傳導(dǎo)途徑Cardiac conduction syst醫(yī)學(xué)電子儀器wiederholen課件The P-wave shows the hearts upper chambers (atria) contracting (depol.)The QRS complex shows the hearts lower chambers (ventricles) contracting The T-wave shows the hearts lower chambers (ventricles) r

28、elaxing (repol.)The U-wave believed to be due repolarization of ventricular papillary muscles.ECG (Electrocardiogram )The P-wave shows the hearts u ECG心電圖典型波形 ECG心電圖典型波形Standard LeadI 導(dǎo)聯(lián) 左上肢LA (+) vs. 右上肢RA (-)II導(dǎo)聯(lián) 右上肢RA (-) vs. 左下肢LL (+) III導(dǎo)聯(lián) 左上肢LA (-) vs. 左下肢LL (+)Standard LeadI 導(dǎo)聯(lián) 左上肢LA (Standar

29、d LeadThe Einthoven limb leads (standard leads) are defined in the following way: Lead I:VI = VL - VRLead II:VII = VF VRLead III:VIII = VF - VLAccording to Kirchhoffs law these lead voltages have the following relationship: VI + VIII = VII hence only two of these three leads are independent. Standar

30、d LeadThe Einthoven lim(A) The circuit of the Wilson central terminal (CT).(B) The location of the Wilson central terminal in the image space (CT). It is located in the center of the Einthoven triangle.Unipolar Measurements單極肢體導(dǎo)聯(lián)Frank N Wilson (1890-1952) (A) The circuit of the Wilson Show that the

31、voltage in lead aVR is 50% greater than that in lead VR at the same instant.Show that the voltage in lead Typical impedance values:放大器輸入阻抗：10 M人體手指到肩部阻抗：400軀干阻抗：20皮膚電極之間的阻抗：幾百幾十KInterference from electric devicesDisplacement circuit from powerline to leadlinesTypical impedance values:InterECG level：

32、 50V - 5 mVEEG level： 10 - 300 V Interference from electric devicesDisplacement circuit from powerline to leadlinesECG level： 50V - 5 mVInterferInterference from electric devicesDisplacement circuit from powerline to leadlinesMinimizing the interference by:Shielding leadlineGrounding every shield in

33、 ECGLowering the skin impedances Z1 = Z2Increasing ZinInterference from electric devDriven-right-leg circuitDriven-right-leg circuitDriven-right-leg circuitDriven-right-leg circuitSumming the currents at the negative input of the op amp, we getThus, substituting (E6.2) into (E6.3) yieldsDriven-right

34、-leg circuitSumming the currents at the ne對(duì)比P.260 (6.7)， Vcm = 10 mVDriven-right-leg circuit對(duì)比P.260 (6.7)， Vcm = 10 mVDriv兩種誘發(fā)電位的比較定義意義非特異性誘發(fā)電位給予不同刺激時(shí)產(chǎn)生的反應(yīng)相同.該電位幅度比較高.沒(méi)有任何特定意義,在臨床診斷中不具有診斷價(jià)值.特異性誘發(fā)電位給予刺激后經(jīng)過(guò)一定的潛伏期，在腦的特定區(qū)域出現(xiàn)的電位反應(yīng)與刺激信號(hào)之間有嚴(yán)格的時(shí)間關(guān)系.電位幅值較小,完全淹沒(méi)在自發(fā)腦電信號(hào)中.電位的形成與特定的刺激之間有嚴(yán)格的對(duì)應(yīng)關(guān)系,可以反映神經(jīng)系統(tǒng)的功能與病變,在臨

35、床上具有診斷價(jià)值.誘發(fā)電位兩種誘發(fā)電位的比較定義意義非特異性誘發(fā)電位給予不同刺激時(shí)產(chǎn)生誘發(fā)試驗(yàn)“事件相關(guān)電位”（event-related potential, ERP）是一種特殊的誘發(fā)電位，通過(guò)有意地賦予刺激以特殊的心理意義，利用多個(gè)或多樣的刺激所引起的腦的電位。它反映了認(rèn)知過(guò)程中大腦的神經(jīng)電生理的變化，也被稱為認(rèn)知電位，也就是指當(dāng)人們對(duì)某課題進(jìn)行認(rèn)知加工時(shí)，從頭顱表面記錄到的腦電位。誘發(fā)試驗(yàn)“事件相關(guān)電位”（event-related pot醫(yī)學(xué)儀器Chapter 7- Blood Pressure 醫(yī)學(xué)儀器Blood pressure measurementDirect measurem

36、ent (invasive,high accurate)Indirect measurement (noninvasive,low accurate) Blood pressure measurementDireIndirect measurements of BPAuscultatory MethodAuscultation: the act of listening, either directly or through a stethoscope or other instrument, to sounds within the body. This method is based on

37、 the fact that pulse waves when first propagate through the brachial artery, generate Korotkoff sounds.Indirect measurements of BPAusIndirect measurements of BPAuscultatory MethodIndirect measurements of BPAusAutomated BP measurement method 1Microphone pick up Korotkoff sound Inflateds and deflates

38、an cuff at a certain rate must be automatically finished Microphone replaces the stethoscopeMicroprocessor is uesed in the systemBlood pressure measurementAutomated BP measurement methoThe oscillometric method(示波法)the observation of oscillations of blood flow during the pulsation.It uses a sphygmoma

39、nometer cuff, like the auscultatory method, but with pressure sensor (transducer) to observe cuff pressure oscillationsThe pressure sensor (within the inflated cuff) detects the pulsation of the artery wall as a pressure vibration. The interpretation of these small vibrations amplitude provide the b

40、lood pressure value. The oscillometric method(示波法)tThe oscillometric method(示波法)OmOsOd3The oscillometric method(示波法)O示波法血壓判定方法固定比率計(jì)算法幅度最大處為平均壓收縮壓和舒張壓根據(jù)經(jīng)驗(yàn)公式計(jì)算突變點(diǎn)方法對(duì)脈搏波包絡(luò)微分，確定舒張壓、收縮壓和平均壓The oscillometric method(示波法)示波法血壓判定方法固定比率計(jì)算法The oscillomet醫(yī)學(xué)儀器Optical Molecular ImagingBioluminescence imaging(BLI)

41、Fluorescence imaging(FI)醫(yī)學(xué)儀器Molecular ImagingHighly specific imaging probes Sensitive imaging systemMolecular ImagingHighly specifMolecular Imaging優(yōu)勢(shì)：更深入細(xì)胞分子水平更早解剖結(jié)構(gòu)改變前Molecular Imaging優(yōu)勢(shì)：Molecular Imaging應(yīng)用領(lǐng)域：腫瘤檢測(cè)藥物研發(fā)基因表達(dá)Molecular Imaging應(yīng)用領(lǐng)域：生物發(fā)光現(xiàn)象是生物體內(nèi)的化學(xué)反應(yīng)將化學(xué)能轉(zhuǎn)化為光能而發(fā)光的現(xiàn)象Bioluminescence生物發(fā)光現(xiàn)象是生物體

42、內(nèi)的化學(xué)反應(yīng)將化學(xué)能轉(zhuǎn)化為光能而發(fā)光的現(xiàn)熒光素酶報(bào)告基因?qū)嶒?yàn)流程制備含有螢光素酶基因的DNA轉(zhuǎn)染提供刺激測(cè)量螢光調(diào)節(jié)序列Luc報(bào)告基因載體報(bào)告基因檢測(cè)Bioluminescence Mark熒光素酶報(bào)告基因?qū)嶒?yàn)流程制備含有螢光素酶基因的DNA調(diào)節(jié)序列Bioluminescence Imaging優(yōu)點(diǎn)：在體無(wú)創(chuàng)傷高特異性高靈敏度，最低檢測(cè)100多細(xì)胞無(wú)電離輻射系統(tǒng)簡(jiǎn)單，操作方便成本低廉Bioluminescence Imaging優(yōu)點(diǎn)：1.GFP的光譜特性 最大激發(fā)波長(zhǎng) 460-490 nm發(fā)射波長(zhǎng) 500-550 nmGFP的特性2.GFP的分子量小（27kDa） 當(dāng)與其它蛋白組成融合蛋白 時(shí)，不影響結(jié)合蛋白的功能GFP的優(yōu)點(diǎn)1.可溶性蛋白，性質(zhì)穩(wěn)定2.熒光強(qiáng)，易加工到其它蛋白質(zhì)序列上3.無(wú)進(jìn)入細(xì)胞問(wèn)題，標(biāo)記可靠4.表達(dá)GFP融合物的細(xì)胞，可