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ID:37240690
大小:801.60 KB
页数:31页
时间:2019-05-11
《动物生理学5呼吸系统生理上》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、5RespirationChemicalreductionofmolecularoxygentoformwateristheprimarysourceofenergyforanimals.Theprincipalsiteforthereactionoccurswithinthemitochondria.Withoutthisreactionlifecannotexistformorethanseconds.CoincidentalwiththereductionofO2istheproductionofCO2;thiscomesmainlyfromoxidativephosphorylati
2、onofglucosewhichalsooccursprincipallyinthemitochondrion.Repirationincludes:Thegasesmustbemovedbetweentheenvironmentandthelungs,usuallyreferredtoas“pulmonaryventilation”ThegasesmustbeexchangedbetweenthespacesinlungandthebloodExchangeofgasesbetweenthebloodandthevarioustissuesmustoccurFinallytransfero
3、fgasesmustoccurwithinthetissuetositesofutilization(forO2)andfromthesitesofproduction(forCO2)5.1pulmonaryventilationGasexchangebetweentheenvironmentandthelungs,usuallyreferredtoas“pulmonaryventilation”Thestructuresneededforpulmonaryventilation:airway,alveoli[æl’viəlai](单数alveolus),andthorax5.1.1肺通气的
4、原理5.1.1.1肺通气的动力直接动力 肺泡与外界环境之间的压力差原动力 节律性呼吸运动Respiratorymovements(呼吸运动)Respiratorymuscle:diaphragm(膈),intercostalmuscle,etalThoraciccavityInspiratorymovement&Expiratorymovement呼吸运动的形式:腹式呼吸和胸式呼吸平静呼吸和用力呼吸Intrapulmonarypressures肺内压平静呼吸吸气时-2~-1mmHg(-0.266~-0.133Kpa)呼气时1~2mmHg(0.133~0.266Kpa)用力呼吸(forcedb
5、reathing)用力吸气-100~-30mmHg用力呼气60~140mmHgThepressureinthoraciccavity(intrapleuralpressures)胸膜腔内压pulmonaryventilation:Aslongasinterplueralpressureremainslessthanatmosphericpressure,thedimensionsofthelungsfollowcloselythedimensionsofthethoraciccavity.Lungmovementsresultsfromcontractionofrespiratorymusc
6、lesassociatedwiththemovementofstructuresinthoraciccavitywallandofthediaphragm.Pleura:surroundingeachlungisaserous(含浆液的)membrane,thepleura.Theoutlayeradherestotheinnerthoracicwallandthediaphragm.Theinnerlayercoversthelungthepotentialspacebetweenthetwolayersiscalledthepleuralcavity,thelayersnormallym
7、oveeasilyovereachotherwithmovementofthethorax.Pressureintheinterpleuralspaceisalwaysnegative.(平静呼吸时)气胸(Pneumothorax)胸膜腔内压=肺内压-肺回缩压当呼吸暂停时 胸膜腔内压=大气压-肺回缩压若以大气压为“0”胸膜腔内压=-肺回缩压胸腔负压也可作用于腔静脉和胸导管,影响静脉血和淋巴的回流。5.1.1.
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