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1.
目的建立一种经兔耳正中动脉穿刺置管进行动脉血压监测新方法。方法健康家兔16只,雌雄不分,体重2.0±0.3k。动物随机分成两组,颈内动脉穿刺置管组(A组)8只,耳正中动脉穿刺置管组(B组)8只。两组均用22G动静脉留置针行穿刺置管后接有创动脉换能器套件联接监护仪监测有创动脉血压的变化,实验后家兔正常饲养7d,观察其死亡率。结果有创动脉压:A组和B组两组差异无统计学意义(P〉0.05);死亡率:A组明显高于B组(P〈0.05)。结论经兔耳正中动脉穿刺置管进行有创动脉血压监测比颈内动脉置管法要好,是一种简单、有效的方法,死亡率低,可以在兔的动物实验中推广。  相似文献   

2.
动物行为学是用于评价动物学习记忆的基本实验手段,广泛应用于生理病理机制研究及药效评价。评价大小鼠学习记忆行为检测方法根据实验原理可分为惩罚性、自发性和奖励性三类,其中奖励性操作条件反射实验是基于奖励性原理和斯金纳条件反射原理的行为学检测方法,为检测动物学习记忆中的高级认知功能提供了一种更全面更精细的检测手段,尤其适合于现代高科技条件下执行复杂操作任务时的认知作业能力评价。本文对奖励性操作性条件反射实验的发展历程、实验装置、实验方法及应用领域等方面进行了概述,为此类方法今后在国内学习记忆行为学领域的研究与应用提供参考。  相似文献   

3.
目的将奖励性操作式条件反射方法应用于学习记忆研究。方法首次采用奖励性操作式条件反射方法,设置单次操作训练、连续多次操作训练、信号辨识与消退四种检测模式,研究Wistar大鼠和SHR大鼠学习记忆能力。结果奖赏训练中,SHR组鼻触次数显著增多(vs.Wistar&Donepezil,P〈0.05);单次操作训练中,三组动物对操作反应的获得无显著差异;连续多次操作学习任务中,SHR组错误操作次数增多(vs.Wistar,P〈0.05),奖赏获得次数减少(vs.Donepezil,P〈0.001),反应准确率显著降低(vs.Wistar&Donepezil,P〈0.05);信号辨识任务中SHR组错误反应次数显著增多(vs.Wistar&Donepezil,P〈0.05),而反应准确率降低,组间差异有显著性(vs.Wistar&Donepezil,P〈0.05);消退实验中,三组动物差异无显著性。神经递质检测发现,SHR组大鼠谷氨酸[(1.0639±0.07086)mg/g]、乙酰胆碱[(2.7760±0.2609)μg/g]与五羟色胺[(1.2200±0.1137)μg/g]含量均显著低于Wistar组大鼠(P〈0.05),多奈哌齐组大鼠乙酰胆碱含量显著增加[(3.9344±0.2747)μg/g](vs.Wistar,P〈0.05;vs.SHR,P〈0.001)。结论奖励性操作式条件反射方法可作为一种正性增强条件反射检测新方法应用于大鼠学习记忆研究。  相似文献   

4.
目的 直接动脉血压(arterial blood pressure,ABP)连续监测是侵入式的,传统袖带式的间接血压测量法无法实现连续监测。既往利用光学体积描记术(photoplethysmography,PPG)实现了连续无创血压监测,但其为收缩压和舒张压的离散值,而非ABP波的连续值,本研究期望基于卷积神经网络-长短期记忆神经网络(CNN-LSTM)利用PPG信号波重建ABP波信号,实现连续无创血压监测。方法 构建CNN-LSTM混合神经网络模型,利用重症监护医学信息集(medical information mart for intensive care,MIMIC)中的PPG与ABP波同步记录信号数据,将PPG信号波经预处理降噪、归一化、滑窗分割后输入该模型,重建与之同步对应的ABP波信号。结果 使用窗口长度312的CNN-LSTM神经网络时,重建ABP值与实际ABP值间误差最小,平均绝对误差(mean absolute error,MAE)和均方根误差(root mean square error,RMSE)分别为2.79 mmHg和4.24 mmHg,余弦相似度最大,重建ABP值与实际ABP值一致性和相关性情况良好,符合美国医疗器械促进协会(Association for the Advancement of Medical Instrumentation,AAMI)标准。结论 CNN-LSTM混合神经网络可利用PPG信号波重建ABP波信号,实现连续无创血压监测。  相似文献   

5.
郑坚  潘敬运 《生理学报》1991,43(4):330-337
The purpose of this study is to investigate the role of paraventricular nucleus of the hypothalamus (PVN) and alpha 1 adrenergic receptor of PVN in the pressor responses to stimulation of renal afferent nerve in alpha 1-chloralose-anesthetized cats with carotid sinoaortic denervation and vagotomy. The pressor response to stimulation of renal afferent nerve consisted of a primary and a second components. The primary component response was completely blocked while the second component was not blocked by autonomic blocking agents (hexomethonium and atropine). Bilateral lesions of PVN greatly attenuated the pressor response before and after autonomic blockade. Intracerebroventricular and PVN injection alpha 1, adrenergic antagonist (prazosin) significantly decreased in the pressor response to stimulation of renal afferent nerve. These results indicate that paraventricular nucleus of the hypothalamus and alpha 1 adrenergic receptors in central nervous system, especially in PVN, play an important role in the pressor responses to stimulation of renal afferent nerve.  相似文献   

6.
电刺激乌拉坦麻醉的大鼠下丘脑外侧区(LH)可使缰核(Hb)内51.0%的单位兴奋,15.7%的单位抑制,其中发生兴奋反应的单位有15.4%可被逆行激活。双侧Hb内微量注射利多卡因,电刺激LH引起的升压反应可被阻断42.0±28.0%;反之,双侧LH内微量注射利多卡固,电刺激Hb引起的升压反应可被阻断62.0±26.4%。结果表明,LH与Hb在血压调节中相互依赖,具有协同作用。  相似文献   

7.
分别向杏仁内侧核(MAN)内微量注射去甲肾上腺素(NA)或神经肽Y(NPY)。NA引起血压升高,心率加快;而NPY引起血压降低,心率减慢。如果注入不能改变血压的小剂量NPY,则可抑制NA引起的升压作用,反映NPY与NA共同参与心血管活动的中枢性调节过程。向MAN中注射NPY后血中NA的含量也相应降低,表明在MAN中注射NPY引起的血压、心率反应是通过降低血浆中NA含量而实现的。  相似文献   

8.
本研究的目的是在氯醛糖麻醉、颈动脉窦、主动脉弓去神经和切断迷走神经的猫中探讨室旁核和室旁核α_1肾上腺素受体在刺激肾神经传入纤维引起的升压反应中的作用。刺激肾神经中枢端可引起动脉血压明显升高。这种血压升高由两个成分组成。第一成分可被植物性神经阻断剂六烃季铵和阿托品所阻断,第二成分不能被植物性神经阻断剂所阻断。双侧室旁核毁损后,植物性神经阻断前、后刺激肾神经中枢端引起的升压反应都明显减弱。侧脑室和室旁核微量注射α_1肾上腺素受体拮抗剂哌唑嗪,可显著抑制刺激肾神经传入纤维引起的升压反应。这些结果表明,室旁核和中枢的,尤其在室旁核的α_1肾上腺素受体在刺激肾神经传入纤维引起的升压反应中起重要作用。  相似文献   

9.
急性生理功能和慢性健康状况评分不仅对评估ICU患者的预后有着重要作用,而且在医院感染目标性监测中起到不可或缺的作用。综述了这方面的最新研究进展,旨在推荐在医院感染目标性监测中用急性生理功能和慢性健康状况评分评估患者病情严重程度,用其调整ICU目标性监测的医院感染发生率,为各家医院比较医院感染发生率提供客观、统一的评价标准。  相似文献   

10.
目的:探讨时间序列ARIMA模型在时间序列资料分析中的应用,建立咳嗽症状监测数据的预测模型.方法:采用条件最小二乘方法估计模型参数.通过对数转换及差分方法使原始序列平稳,按照残差不相关原则、简洁原则确定模型结构,依据AIC和SBC准则确定模型阶数,最终建立起ARIMA预测模型.结果:ARIMA(1,1,1)模型拟合效果较好,方差估计值为0.7361,AIC=95.6092,SBC=98.8310,对模型进行白噪声残差检验,提示残差为白噪声.结论:症状监测这种具有时间序列特点的资料可以用ARIMA模型来进行拟合估计.本文中预测结果可信区间比较宽,可能是因为时间序列比较短,还未能考虑到季节趋势.另外,所用监测数据是在中小学生在校发生症状的人数,故在节假日会出现缺失值,样本量和时间长度均有限,可能影响模型估计的准确性,本研究的结论还有待于将来资料积累后进行修正和深化.  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.
NO对家兔Oddi括约肌肌电活动和血压的影响   总被引:4,自引:1,他引:3  
Zhang M  Ding CH  Zhang LW  Yang SY 《生理学报》1998,50(6):618-622
应用32只家兔观察一氧氮对Oddi括约肌肌电和血压的影响。静脉注射NO合酶抑制剂N^G-硝基-L-精氨酸,可见SO肌电振幅增大和血压升高,L-NNA所致的肌电活动增强可L-精氨酸反转。  相似文献   

13.
We evoked changes in lower lip blood flow and systemic arterial blood pressure by electrically stimulating the central cut end of the lingual nerve in artificially ventilated, urethane-anesthetized, cervically vago-sympathectomized cats, rats, rabbits, and guinea pig. The systemic arterial blood pressure changes were species-dependent: increases in rat, consistent decreases in rabbit and guinea pig, and variable among individuals in cat. In cat and rabbit, lip blood flow increases, which occurred only ipsilaterally to the stimulated nerve and showed no statistically significant correlation with the systemic arterial blood pressure changes. In rat, the ipsilateral lip blood flow increase was markedly greater than the contralateral one, and although there was a significant correlation between each of them and the systemic arterial blood pressure changes, the ipsilateral increase presumably included an active vasodilatation. In guinea pig, lip blood flow decreased on both sides in proportion to the systemic arterial blood pressure reductions. Thus, species variability exists in the sympathetic-mediated systemic arterial blood pressure changes and parasympathetic-mediated lip blood flow responses themselves, and in the relationship between them.Abbreviations a.u. arbitary units - LBF lip blood flow - LN lingual nerve - SABP systemic arterial blood pressure - SP substance P - Vsp trigeminal spinal nucleusCommunicated by I.D. Hume  相似文献   

14.
Hematopoetic stem cells (HSC) are the progenitors for the lympho-hematopoietic system, with long lifespan and high proliferation potential. Transplantation of HSC from bone marrow or peripheral blood represents a standard therapy in severe hematological conditions. A possible alternative source of HSC is the umbilical cord blood, prepared by various separation procedures followed by expansion in cultures supplemented with hematopoietic growth factors. In order to check the effects of placental conditioned medium (PCM) from placental cells culture upon viability of HSC, we added plasma, PCM, dimetil sulfoxyde or hemin in HSC cultures. Flow cytometry or direct scoring of solid cultures using CD45+, CD34+, CD71+ and CD14+ fluorescent-labeled monoclonal antibodies evaluated the effects upon cell proliferation and colony forming ability of HSC cultures, versus controls. PCM produced the highest proliferation, followed by plasma, DMSO and hemin. PCM improved the survival time and maintained a higher proportion of immature cells. PCM stimulates the differentiation towards myeloid lineage progenitor cells (>90% being CD45+), increasing the percentage of CD14+, granulocites /monocytes precursors. It is highly suggestive that PCM contains growth factors or cytokines, which regulate the development of HSC. Characterization of these factors is in progress.  相似文献   

15.
Adult male baboons were behaviorally conditioned to extend an arm outside of the living cage and to accept repeated cuff inflations for manual auscultatory blood pressure measurements. Frequency distributions of systolic and diastolic blood pressure for both normotensive and renovascular hypertensive baboons generally were normally distributed. The procedure accurately tracked rapid changes in blood pressure after oral administration of antihypertensive drugs. Advantages over direct arterial cannulation for blood pressure measurement during extended, chronic experiments are discussed.  相似文献   

16.
[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   

17.
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   

18.
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,左心射血分数(LVEF)(61.33±2.16)%。患者签署知情同意书后,选择心功能正常需要监测动、静脉血流动力学变化的患者6 例,连续同时桡动脉、颈内静脉逐搏取血,测定PaO2。选取2个典型呼吸周期,用于分析同时段动、静脉血气的波浪式变化。分别比较患者血氧分压最高和最低值,以验证同时段动、静脉血气是否都存在周期性波浪式信号变化。此外,将患者动脉、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。所有患者动脉血气中PaO2均呈现明显的波浪式变化(P<0.05),幅度是(9.96±5.18)mmHg,是均值的(8.09±2.43)%。患者静脉血气中PaO2波动幅度并不明显,为(1.63±0.41)mmHg,是均值的(3.91±1.22)%,与动脉血气组相比有明显统计学差异(P<0.05)。结论: 采用同时连续逐搏动、静脉取血血气分析法证实,患者自主呼吸时动脉血气有明显的周期性波浪式变化信号,而静脉血气几乎没有周期性波浪式变化信号(很弱),说明动脉血气波浪式信号主要是由于肺通气过程中吸气和呼气期产生肺泡中氧分压规律性上升和下降,通过离开肺毛细血管与肺泡氧气压力平衡的动脉化血液,经过左心室搏血进入动脉血管系统所致。  相似文献   

19.
A pressure to voltage transducer is used along with a cuff, in a PC-based blood pressure and pulse rate monitoring system for human body. During the blood pressure measurement cycle, the output voltage of the pressure to voltage transducer is recorded digitally using a data acquisition system. The recorded data are then analyzed using software routines to determine the blood pressure and pulse rate of the person under test. However, it is difficult to identify the points of systole and diastole correctly from the recorded data. This paper presents the technique that may be used to determine the systolic and diastolic pressure from the collected data.  相似文献   

20.
Vasopressor responses in urethane-anaesthetized rats were evoked by a new peptide from chicken brain, LPLRFamide, and the immunochemically related molluscan neuropeptide, FMRFamide. In doses of 50 to 200 nmol X kg-1, i.v., both peptides produced a rapid increase in arterial pressure that returned to basal in 1-2 min. When given intracisternally in similar doses the two peptides again increased arterial pressure, but the time to peak response (1-2 min) and the duration of the responses (5-8 min) were prolonged. There was a marked, reversible, specific, tachyphylaxis following intracisternal but not intravenous injection of LPLRFamide, indicating separate sites of action after administration by these routes. Guanethidine and phentolamine blocked the responses to both intravenous and intracisternal administration, and hexamethonium significantly reduced the response to intracisternal administration. Both by intravenous and intracisternal routes it is therefore likely that responses are mediated by noradrenaline release from sympathetic endings. In addition, following adrenalectomy and propranolol the response to intravenous (but not intracisternal) LPLRFamide was increased, suggesting that adrenaline released from the adrenal medulla might act at beta-adrenoreceptors causing vasodilatation. The physiological significance of these observations remains to be established, but it is significant that peptides immunochemically related to FMRFamide and LPLRFamide occur in areas of rat brain concerned with autonomic control.  相似文献   

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