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1.
目的:人动脉血来源是右心系统并在肺脏进行气体交换的静脉血,右心系统的静脉血是否存在波浪式信号目前尚没有证据支持,本研究旨在对比同时间动、静脉血中信号的连续变化特点.方法:选择心功能正常,需要连续监测动脉血流动力学变化的患者6例,4男2女,年龄(59.00±16.64)岁,体质量(71.67±10.37)kg,左心射血分...  相似文献   

2.
目的: 本研究旨在发现不同通气模式下动脉血气的变化特点。方法: 选择心功能正常,需要连续监测动脉血流动力学变化的患者6 例,4男2女,年龄(59.00±16.64)岁,体质量(71.67±10.37)kg,左心射血分数(LVEF)(61.33±2.16)%。患者签署知情同意书后,分别于正常呼吸、憋气20 s以及高潮气量过度通气状态下连续15~16次心跳桡动脉、颈静脉逐搏取血,测定PO2,用于分析三种呼吸状态下动、静脉血气的变化特点。分别比较患者相邻最高和最低值,以验证三种呼吸状态下动、静脉血气是否都存在周期性波浪式信号变化;此外,将患者动、静脉血气周期性波浪式信号的变化幅度进行统计学t检验分析,比较有无差异。结果: 共6例ICU 住院监护患者, 抽取动、静脉血液充满肝素化细长塑化管需要15~16次心跳,即取血需要15~16次心跳,全部覆盖超过2个呼吸周期。患者正常呼吸、憋气20 s以及高潮气量通气状态下动脉血气中PaO2呈现波浪式变化,幅度分别是(9.96±5.18)mmHg,(5.33±1.55)mmHg和(13.13±7.55)mmHg,分别是各自均值的(8.09±2.43)%,(5.29±2.19)%,(10.40±2.68)%,高通气量呼吸模式波浪式变化幅度大于正常呼吸模式(P<0.05),正常呼吸模式波浪式变化幅度大于憋气状态(P<0.05)。正常呼吸、憋气20 s以及高潮气量通气状态下静脉血气中PO2未呈现波浪式变化,幅度分别是(1.63±0.41)mmHg,(1.13±0.41)mmHg和(1.31±0.67)mmHg,分别是各自均值的(3.91±1.22)%,(2.92±1.12)%,(3.33±1.81)%,都显著低于同状态下动脉血气,但组间差异不明显。结论: 分别于三种通气状态下采用连续逐搏动脉取血血气分析法证实,患者高通气状态呼吸时动脉血气的周期性波浪式变化信号增强,憋气时波浪式呼吸变化信号变弱,而静脉血氧分压波浪式变化幅度于三种呼吸状态下都不明显。说明肺通气导致肺换气是影响动脉血液波浪式信号幅度的直接决定性因素。  相似文献   

3.
目的: 心力衰竭患者呼吸调控异常的机制众说纷纭,特别是动脉血气周期性波浪式变化信号的改变及其与心功能的关系尚缺乏直接的试验证据。本文依据心力衰竭患者动脉血气周期性波浪式变化信号的降低幅度,探讨心力衰竭导致呼吸调控异常的机制。方法: 选择5名心力衰竭患者,连续桡动脉逐搏取血,测定PaO2,PaCO2,pHa和SaO2。选取2个典型呼吸周期,用于分析动脉血气的波浪式变化。比较患者相邻最高和最低值,以验证是否存在周期性波浪式信号变化。此外,将心力衰竭患者与心功能正常患者动脉血气周期性波浪式信号的变化幅度进行统计学t检验分析,比较有无差异。结果: 心力衰竭患者包括2例外科手术和3例ICU住院监护患者,4男1女,年龄(69±7)岁,身高(169±10)cm,体质量(75±19)kg,左心射血分数(LVEF)=(38±3)%。动脉血液充满肝素化细长塑化管需要17±2次心跳,即取血需要17±2次心跳,覆盖超过2个呼吸周期。心力衰竭患者PaO2,PaCO2,[H+]a和SaO2均呈现明显的波浪式变化(P<0.05),幅度分别是(7.94±2.02)mmHg,(1.18±0.56)mmHg,(0.54±0.17)nmol/L和(0.21±0.07)%,分别是各自均值的(6.1±1.5)%,(3.2±1.5)%,(1.5±0.5)%和(0.2±0.1)%。与心功能正常患者比较,动脉血气波浪式变化幅度呈现明显降低趋势,但仅PaO2和[H+]a有明显统计学差异(P<0.05)。结论: 采用连续逐搏动脉取血血气分析法证实,心力衰竭患者自主呼吸时动脉血气也有周期性波浪式变化信号,但其变化幅度较心功能正常患者明显降低。  相似文献   

4.
目的: 建立动脉逐搏取血血气分析法,在人体实验中验证呼吸调控核心信号——PaO2,PaCO2和[H+]a是受呼吸影响的周期性、波浪式变化信号,而不是传统理念上误认的稳定水平信号。方法: 选择心功能正常、Allen试验阴性需要监测动脉血流动力学变化的患者6例。在左侧桡动脉穿刺,连接肝素化塑化管(3 mm×1 000 mm),注满血液并计数血液注满所需心跳次数。用止血钳将塑化管钳闭成与心跳次数相对应的分段后,迅速置于冰水中,立即进行血气分析。选取每位患者的2个典型波浪式周期,用于分析2对最高-最低和最低-最高共4个测定值,取平均值。对相邻最高和最低值作统计学配对t检验。结果: 血液注满塑化管需要16±2次心跳,均覆盖超过2个呼吸周期。每个呼吸周期是5±0.6次心跳。PaO2、PaCO2、[H+]a和SaO2都呈现出明显的波浪式变化(相邻高点与低点比较,P<0.05),PaO2、PaCO2、[H+]a和SaO2的波浪幅度分别是(11.28±1.13)mmHg,(1.77±0.89)mmHg,(1.14±0.35)nmol/L和(0.52±0.44)%;波浪幅度分别是其平均值的(7.7±1.1)%,(5.1±2.5)%,(3.1±1.0)%和(0.5±0.4)%。结论: 动脉延长管连续取血,按心跳次数分隔血样,血气分析法简单易行,为验证动脉血气受呼吸影响的周期性波浪式信号提供了可靠证据。本方法为原创,技术操作层面仍需提高熟练程度,增加志愿者和试验样本的数量进一步探索此类信号的临床检测可靠性及其与临床疾病的关系。  相似文献   

5.
目的:本研究旨在发现不同通气模式下动脉血气的变化特点.方法:选择心功能正常,需要连续监测动脉血流动力学变化的患者6例,4男2女,年龄(59.00±16.64)岁,体质量(71.67±10.37)kg,左心射血分数(LVEF)(61.33±2.16)%.患者签署知情同意书后,分别于正常呼吸、憋气20 s以及高潮气量过度通...  相似文献   

6.
目的: 为探讨新生儿自主呼吸产生机制,前文已对新生儿出生后自主呼吸开始前脐带动静脉氧气和二氧化碳差值进行了人群组间分析;而本部分则对相关信息进行个体化分析。方法: 在产前经所有胎儿父母签署知情同意书,新生儿出生后还没有呼吸之前在脐带动脉和脐带静脉分别连续逐搏取血,仅有3例同时采集到Pua和Puv血液样本进行血气分析测定,计算分析脐带静脉和脐带动脉的异同和动态变化。结果: 虽然准备了数十产妇,但仅有3例同时采集到Pua和Puv血液样本,同一时间的PuvO2显著高于PuaO2P均<0.01),平均相差(24.17±7.09) mmHg;而PuvCO2显著低于PuaCO2P均<0.01),平均相差(-7.67±3.70) mmHg。在同一时间的Puv-uaO2显著高于Puv-uaCO2P<0.05)。结论: 新生儿出生后自主呼吸前,全部氧气供应由脐带静脉运输,只要胎盘开始剥离则新生儿的PuaO2随时间(心跳次数)逐渐降低,当PuaO2达到触发呼吸阈值(最低值)诱发第一次吸气开始其自主呼吸。  相似文献   

7.
目的: 胎儿没有实际上的呼吸,新生儿出生后才开始呼吸,我们假设人的第一次呼吸主要是由于低氧而触发。本研究对流经主动脉体外周化学感受器后的脐带动脉血液氧分压(PuaO2)变化规律和下限进行分析以探讨新生儿自主呼吸产生机制。方法: 选择签署知情同意书的正常分娩产妇数十例,仅14例新生儿在自主呼吸开始前成功完成脐带动脉或静脉置管。分别进行逐搏取血及顺序血气分析,计算血气指标的平均值、最高值和最低值,统计比较脐带动静脉的异同。结果: 在14例新生儿自主呼吸开始前完成采集脐带动脉(Pua)样本9例,脐带静脉(Puv)样本8例。就PO2而言,所有9例PuaO2随时间(心跳次数)呈逐渐降低倾向,直至在自主呼吸产生大约8~10次心跳后Pua挛缩、基本上无法取得足够的血样。PuaO2平均值是(25.94±6.79,18.04~37.51)mmHg,最高值是(29.11±6.46,23.00~45.90)mmHg,最低值是(21.34±5.54,14.00~33.60)mmHg;但PuaCO2变化趋势和规律则不够稳定,PuaCO2平均值是(47.26 ±7.71) mmHg。PuvO2随时间(心跳次数)虽也呈逐渐降低趋势,但多数还呈现随母亲呼吸节律的规律性交替升降的倾向,特别是母亲吸氧时。所有8例PuvO2平均值是(53.35±21.35,32.56~100.73)mmHg,最高值是(90.38±48.44,43.40~153.00)mmHg,最低值是(36.96±14.90,24.80~73.80)mmHg;PuvCO2平均值是(41.04±6.44)mmHg。虽然有着较大的个体差异,但 PuvO2平均值、最高值和最低值均显著较PuaO2高(P<0.05);PuvCO2虽略低于PuaCO2,但无显著差异(P>0.05)。结论: 胎儿娩出为新生儿后自主呼吸前PuaO2随时间(心跳次数)逐渐降低,在达到触发呼吸的阈值时诱发第一次吸气,从而开始自主呼吸。  相似文献   

8.
目的: 探讨心力衰竭患者在运动期间诱发的异常波浪式呼吸模式(EIOB)的临床特点及发生机制。方法: 回顾分析38例NYHA Ⅲ-Ⅳ级患者完成的症状限制性功率递增极限心肺运动试验(CPET)。观察分析计算心力衰竭患者在CPET中EIOB的发生时间、频率、振幅等临床特点。结果: 本组患者男17女21在38例患者中,31例发生EIOB,发生率为81.6%。EIOB组每分通气量(VE )波浪振幅是(12±4)L/m(为平均值的81%±30%),周期(77.0±20.0)s。EIOB组中OB发生在运动前、运动中功率低于无氧阈时、恢复期或者全程分别为24、31、4和4例;除VE 外,在CPET的各项参数中,全部31例患者均表现EIOB的指标为VO2、VCO2、RER和PETO2;29例患者 VE / V CO2、VO2/ VE 和BF出现EIOB;26例患者PETCO2出现EIOB;25例患者VT、VO2/HR出现EIOB;2例患者HR出现EIOB。结论: 严重心力衰竭患者易发生EIOB。就心脏功能对呼吸调控的影响及心衰患者呼吸异常发生机制进行了探讨。  相似文献   

9.
目的: 在初步验证超快反应聚合物基质光纤氧传感器及其测定系统记录颈动脉氧分压(PaO2)连续动态变化使用基础上,为了分析探讨肺通气对PaO2连续动态变化的影响,我们设计本活体整体动物实验观察研究。方法: 选择杂种山羊4只,全身麻醉气管插管空气机械通气下,切皮直接暴露把后接测定系统的氧传感器直接插入左侧颈动脉连续记录PaO2动态变化。正常分钟通气量机械通气分别通过三种潮气量实施:正常潮气量(潮气量VT=15 ml/kg、呼吸频率Rf=20 bpm)、减半潮气量(VT减半、Rf加倍)和加倍潮气量(VT加倍、Rf减半)。三种潮气量通气时间分别稳定10~15 min,选取后180 s分析计算PaO2平均值、呼吸间PaO2变化的升降幅度和肺-颈动脉延迟时间。以ANOVA及两两比较统计学差异分析不同潮气量的影响。结果: 活体山羊正常通气量机械通气实验时心率和血压均稳定;肺-颈动脉延迟时间为1.4~1.8 s(约为此时的3次心跳)。机械通气正常潮气量下PaO2平均值在(102.94±2.40,99.38~106.16)mmHg,升降幅度是(21.43±1.65,19.21~23.59)mmHg,占平均值的(20.80±1.34,18.65~22.22)%;减半潮气量下,PaO2平均值维持在(101.01±4.25,94.09~105.66)mmHg,虽略降但不显著(与正常机械通气比较P>0.05),但PaO2升降变化幅度却显著降低为(18.14±1.43,16.46~20.05) mmHg,占平均值的(17.95±1.07,16.16~18.98)%(与正常机械通气比较P<0.01);加倍潮气量机械通气下,虽仅略升的PaO2平均值维持在(106.42±4.74,101.19~114.08)mmHg(与正常机械通气比较P>0.05,与减半潮气量机械通气比较P<0.05),但PaO2升降幅度却显著增大为(26.58±1.88,23.46~28.46)mmHg,占平均值的24.99%±1.58%(与正常机械通气和减半潮气量比较P均<0.01)。结论: 正常肺通气的吸气和呼气是颈动脉PaO2上升和下降的始动因素。正常通气量机械通气下减半潮气量和倍增潮气量显著改变PaO2升降幅度,但PaO2平均值仅小幅改变,而肺-颈动脉延迟时间相近。  相似文献   

10.
目的: 我们在中国尝试使用超快反应聚合物光纤氧感受器置入整体活体动物动脉血管,再通过光电转换测定系统以记录活体动物颈动脉PO2(PaO2)连续动态的快速变化,为完善整体整合生理学理论体系中循环参与呼吸调控和呼吸循环代谢一体化调控提供实验依据。方法: ①超快反应氧感受器制作、性能及其测定系统标定:在实验室加热总长2 m光纤的远端5 mm部分,拉动直到它成锥形尖端,清洁并干燥后,将1 mm锥形光纤尖端浸涂到发光体掺杂聚合物溶液中,在溶剂快速蒸发同时将其缓慢抽出来形成氧气感测尖端,室温干燥24 h。对完成制作的感受器进行性能标定,并于第37日重复标定。②动物实验:在潍坊医学院实验室对山羊全麻气管插管氧气机械通气下,切皮暴露双颈动脉和左侧股动脉,分别把超快反应氧传感器直接插入动脉中,通过光导纤维、激发与检测Y型光纤耦合器经光电转换连接到个人电脑,实现机械通气下活体山羊颈动脉PaO2的连续动态反应,主要分析PaO2的呼吸间波浪式交替升降和肺-颈动脉时间延迟。结果: 该置入式超快反应氧传感器在液相的响应时间为100 ms。活体山羊实验40%~60%氧气机械通气心率和血压稳定,左和右颈动脉PaO2随着呼吸机的吸气和呼气呈现波浪式上升和下降的呼吸交替现象,幅度高达15 mmHg;左侧股动脉位置记录的信息噪音显著干扰PaO2变化。肺-颈动脉时间延迟是在吸气和呼气开始后1.5~1.7 s左侧和右侧颈动脉PaO2都开始上升和下降;即肺通气开始后3次心跳,左心室可把肺毛细血管后动脉化的肺静脉血液送到外周化学感受器位置中断吸气切换为呼气和中断呼气切换为吸气,如此实现吸呼周而复始。结论: 活体动物置入动脉的超快反应氧传感器及其测定系统可测定PaO2生理性波浪式变化,能为整体整合生理学医学新理论体系中解释吸气和呼气相互切换的机制提供实验依据。  相似文献   

11.
Increased gastrointestinal absorption and urinary excretion of zinc has been confirmed in experimental and clinical studies on primary arterial hypertension as a result from changes of intracellular and extracellular zinc content. In arterial hypertension, the levels of zinc in serum, lymphocyte, and bone decrease while increasing in heart, erythrocytes, kidney, liver, suprarenal glands and spleen. These changes result in the loss of zinc homeostasis that leads to various degrees of deficiency, not entirely compensated by nutritional factors or increased absorption in the gastrointestinal tract. Loss of zinc homeostasis can be both cause and effect of high blood pressure. In the present review, the role of zinc metabolism changes and its mechanisms in arterial hypertension are discussed.  相似文献   

12.
Platelet‐derived growth factor (PDGF) has been implicated in the pathogenesis of arterial atherosclerosis and venous neointimal hyperplasia. We examined the effects of PDGF isoforms on smooth muscle cells (SMCs) from arterial and venous origins in order to further understand the differential responsiveness of these vasculatures to proliferative stimuli. Serum‐starved human arterial and venous SMCs exhibited very different proliferative responses to PDGF isoforms. Whereas, proliferation of arterial SMCs was strongly stimulated by PDGF‐AA, venous SMCs showed no proliferative response to PDGF‐AA, but instead demonstrated a significantly greater proliferative response to PDGF‐BB than arterial SMCs. Part of this difference could be attributed to differences in PDGF receptors expression. There was a 2.5‐fold higher (P < 0.05) density of PDGF receptor‐α (PDGF‐Rα) and a 6.6‐fold lower (P < 0.05) density of PDGF‐Rβ expressed on arterial compared to venous SMCs. Concomitant with an increased proliferative response to PDGF‐AA in arterial SMCs was a marked PDGF‐Rα activation, enhanced phosphorylation of ERK1/2 and Akt, a transient activation of c‐Jun NH2‐terminal kinase (JNK), and a significant reduction in expression of the cell‐cycle inhibitor p27kip1. This pattern of signaling pathway changes was not observed in venous SMCs. No phosphorylation of PDGF‐Rα was detected after venous SMC exposure to PDGF‐AA, but there was enhanced phosphorylation of ERK1/2 and Akt in venous SMCs, similar to that seen in the arterial SMCs. PDGF‐BB stimulation of venous SMC resulted in PDGF‐Rβ activation as well as transactivation of epidermal growth factor receptor (EGF‐R); transactivation of EGF‐R was not observed in arterial SMCs. These results may provide an explanation for the differential susceptibility to proliferative vascular diseases of arteries and veins. J. Cell. Biochem. 112: 289–298, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

13.
Most cases of a predisposition to venous thrombosis are caused by resistance to activated protein C, associated in 95% of cases with the Factor V Leiden allele (FVL or R506Q). Several recent studies report a further increased risk of thrombosis by an association between the AB alleles of the ABO blood group and Factor V Leiden. The present study investigated this association with deep vein thrombosis (DVT) in individuals treated at the Hemocentro de Pernambuco in northeastern Brazil. A case-control comparison showed a significant risk of thrombosis in the presence of Factor V Leiden (OR = 10.1), which was approximately doubled when the AB alleles of the ABO blood group were present as well (OR = 22.3). These results confirm that the increased risk of deep vein thrombosis in the combined presence of AB alleles and Factor V Leiden is also applicable to the Brazilian population suggesting that ABO blood group typing should be routinely added to FVL in studies involving thrombosis.  相似文献   

14.
目的:探索一种新的、可靠的模型,用于惊恐条件反射的相关研究。方法:通过使用条件刺激(声音)和非条件刺激(足部电击)相结合的方法,可使动物对条件刺激产生惊恐反应。同时对动脉血压进行长期监测并测定利多卡因阻断杏仁基底外侧核群前后的血压变化。结果:该惊恐条件反射建立后(需经4d训练),单独给予动物条件刺激即可引起血压明显升高。我们将它作为条件反射已形成的标志。此时,用利多卡因阻断杏仁基底外侧核群的作用,单独给予动物条件刺激不再引起血压明显升高。结论:慢性动脉血压监测模型在惊恐条件反射的研究中是一种可靠的动物模型。  相似文献   

15.
[Purpose] The purpose of this study was to assess changes in blood glucose level, blood pressure, and arterial stiffness after a 75 g oral glucose tolerance test (OGTT) in elderly women aged over 65 years with hypertension and either normal glycemic control, impaired fasting glucose tolerance, or diabetes mellitus. We also wished to investigate the relationship between stages of diabetes and physical fitness.[Methods] A total of 24 elderly women with hypertension were assigned to a control group (CON; n=7), impaired fasting glucose group (IFG; n=9), and diabetes mellitus group (DM; n=8). In each group, blood glucose level, brachial ankle pulse wave velocity (PWV), and blood pressure were measured at baseline as well as 60 and 120 minutes after a 75 g OGTT. Physical fitness factors such as hand grip strength, balance test, 4 m gait speed test, chair stand test, short physical performance battery, and 6-minute walking test were subsequently assessed.[Results] In all three groups, blood glucose levels were significantly increased at 60 and 120 minutes after a 75 g OGTT. In the DM group, blood glucose levels were significantly higher before and after a 75 g OGTT than in the CON group. In the CON group, PWV was significantly increased at 60 minutes after a 75 g OGTT; however, there were no changes in other groups after glucose ingestion. In the CON group, systolic and diastolic blood pressures were significantly decreased at 60 and 120 minutes after a 75 g OGTT compared to baseline. However, there was no change in blood pressure after ingestion in the DM group. The IFG group had greater grip strength than the CON group; however, there were no differences in other variables between the groups.[Conclusion] After a 75 g OGTT, elderly women with hypertension and diabetes maintain higher blood glucose levels compared to those with hypertension alone. Unlike elderly women with hypertension alone, those with hypertension and diabetes did not show changes in arterial stiffness and blood pressure after a 75 g OGTT. Therefore, elderly women with hypertension and diabetes may not be able to control their blood vessels following a 75 g OGTT due to impaired vascular endothelial function. Moreover, there was no association between diabetes stage and physical fitness in elderly women with hypertension.  相似文献   

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