自主过度通气试验对不同呼吸衰竭患者低氧血症的影响及临床意义

目的研究自主过度通气试验对不同呼吸衰竭患者低氧血症的影响及其临床意义。方法在睡眠中心就诊的OSAHS患者中选择23例日间低氧、高二氧化碳患者,测定其FEV1占预计值的百分比、FEV1/FVC%、血气分析、呼吸中枢低氧反应性(ΔVE/ΔSa O2)、高CO2反应性(ΔVE/ΔPa CO2),并比较其自主过度通气前后的脉搏血氧饱和度、动脉血氧分压的变化。结果患者的ΔVE/ΔSa O2及ΔVE/ΔPa CO2低于正常,分别为(-0.098±0.07)L·min-1·%-1和(0.539±0.61)L·min-1·mm Hg-1;肺功能在正常范围者自主过度通气前后脉搏血氧饱和度分别为(87.69±3.7)%和(96.92±1.1)%,动脉血氧分压分别为(59.16±13.04)mm Hg和(81.2±11.2)mm Hg,较过度通气前显著升高,可达到正常范围,而存在阻塞性通气障碍的患者自主过度通气前后脉搏血氧饱和度分别为(86.75±5.2)%和(88.75±4.23)%,动脉血氧分压分别为(59.5±3.5)mm Hg和(60±5.67)mm Hg,较过度通气前改变不明显,不能达到正常范围。结论自主过度通气试验可作为鉴别与肥胖低通气及睡眠呼吸障碍相关的呼吸衰竭与其他具有基础肺疾病或神经肌肉疾病所致呼吸衰竭的一种简便的临床方法。

气力容器式管道产品收发柜部件通气试验

提出了气力容器式管道产品的重要部件收发柜的密封性试验和通过性检验的新方法.经过论证分析,认为漏气产生的噪声可以在收发柜装配完毕后的检验中,通过增加通气试验,准确判断出噪声产生的部位后,采取相应的措施加以预防.试验压力是最重要的技术参数,应模拟实际输送过程中的气流压力,运用气体动力学原理,按实际运行参数计算出系统的总压力损失后,确定试验压力为0.05MPa.异常杂音是收发柜内收发装置联结处的微小错位直接影响容器的顺利通过造成的,设计制作的专用辅具有效地保证了焊接装配质量.以上方法可推广到类似产品的试验、检验与质量控制中去.

术中单侧通气试验对全肺叶切除患者肺功能的评价

目的 :对拟行全肺叶切除的患者进行单侧通气试验评估该侧肺功能。方法 :对32例患者采用双腔气管插管 ,全麻后吸入25 %氧气单侧通气20分钟。结果 :26例患者血氧饱和度在92 %以上 ,行全肺叶切除后均未发生呼吸衰竭。结论 :术中单侧通气试验能客观反映单侧肺功能状态。

超声心动图在过度通气试验中诊断冠心病的价值

为了探讨超声心动图在过度通气试验中诊断冠心病的价值。我院分析了65例拟诊为冠心病的患者。结果显示:敏感性87％,特异性96％,诊断准确率91％。我们认为在过度通气试验(HVT)中利用超声心动图诊断冠心病是有价值的。

早复极患儿高通气试验诱发恶性室性心律失常

患儿男、12岁,因睡眠中发生一过性意识丧失伴抽搐、小便失禁而行脑电图检查,结果为阴性,患儿姐姐也有同样情况。两周后,患儿睡眠中再发晕厥并再行脑电图检查。检查中行通气试验60秒时,出现短联律间期的室早（〈200ms）、心电图短长短现象,并发生多形性室速。心电图可见长RR间期后J波幅度增高（图1）。复习前次脑电图检查高通气试验时,也有短联律间期的室早,但未诱发室速。

过度通气激发试验诊断高通气综合征的临床应用

目的探讨用PaCO2替代潮气末CO2分压(PeCO2)行过度通气激发试验临床应用的可行性。方法30例疑似高通气综合征患者行过度通气激发试验,用PaCO2为监测指标,同时进行N ijm egen症状学问卷调查。结果24例过度通气激发试验阳性,同时N ijm egen症状学问卷积分达到或超过23分。过度通气后出现严重的呼吸性碱中毒,平均PaCO2为18.86mmHg。结论高通气综合征临床诊断并不困难,主要取决于医师对该病的警惕性。过度通气激发试验为诊断方法之一,结合典型的症状、N ijm egen症状学问卷积分达到或超过23分、排除相应器质性疾病便可诊断。用PaCO2监测可以取代PeCO2,但动脉穿刺要求快速、准确,相对技术要求高、难度大。

中西医结合治疗高通气综合征临床分析

高通气综合征是由于通气过度,超过生理代谢所需而引起的一组综合征,其特征是临床症状可以用过度通气激发试验诱发出来[1],由于对该病认识不足,常被误诊为癔症或神经官能症,现将本院2008年8月—2012年8月收治的31例高通气综合征患者进行分析总结,报告如下。

Path Analysis on the Meteorological Factors Impacting Soil Respiration Rate of Wheat Field

[Objective]The experiment aimed to study the effects of meteorological factors under different weather conditions on soil respiration. [ Method] The path analysis was used to analyze meteorological factors which influenced soil respiration of wheat field under different weather condition and at jointing stage. [ Result] In sunny day, the correlations between ground temperature at 5 cm, solar radiation, air relative humidity, air temperature and soil respiration were all at significant level while solar radiation and ground temperature at 5 cm were the major factors which influenced soil respiration. In cloudy day, solar radiation was a major factor which influenced soil respiration.[ Conclusion] The soil respiration and surplus path coefficient in sunny day were all higher than these in cloudy day, which demonstrated that except influenced by ground temperature, air temperature, solar radiation and air relative humidity, the soil respiration was also influenced by other factors especially biological factor.

伴呼吸衰竭的肥胖低通气综合征患者的呼吸中枢反应性

目的探讨伴呼吸衰竭的肥胖低通气综合征（OHS）患者的呼吸中枢反应性。方法选择2009年1月至2011年12月住院的伴呼吸衰竭的重度肥胖（平均体质指数34．3±2．68，均I〉30ks／m2）14例，行肺功能检查、多导睡眠图监测和自主过度通气试验前后脉搏血氧饱和度（SpO：）测定、动脉血气分析及呼吸中枢低氧反应性（AVE／ASp02）、高CO：反应性（AVE／APaCO2）测定。其中的10例患者经1周的双水平气道正压通气（BiPAP）治疗后行动脉血气分析。结果14例患者均符合Ⅱ型呼吸衰竭的诊断，睡眠呼吸监测发现睡眠呼吸暂停低通气指数（AHI）为（66．6．4±30．1）次／h。FEV，／FVC的预计值均〉70％，不存在明显的阻塞性通气功能障碍。自主过度通气后Pa02和PaCO：均显著改善[（52．5±7．6）比（81．3±11．1）mmHg（1mmHg=0．133kPa）和（50．4±5．3）比（43．2．4±1．9）mmHg，均P=0．001]，Ⅱ型呼吸衰竭均逆转。呼吸中枢AVE／ASp02和AVE／APaC02绝对值均显著低于正常人群水平[（一0．11±0．08）比（-0．38．4±0．04）L·min^-1·％Sp02^-1和0．31（0．18，0．66）比1．20（0．82，1．50）L·min^-1·mmHg^-1，均P〈0．001）]。10例患者在应用BiPAP呼吸机治疗1周后，体重无明显改变，睡眠呼吸紊乱趋于正常；日间PaCO2随治疗显著降低、PaO：明显升高，8例患者白天高CO2的患者的PaCO2恢复到正常水平。结论OHS患者存在睡眠呼吸紊乱及呼吸中枢反应性降低，导致的呼吸衰竭属于“不愿呼吸”类型，自主过度通气试验后呼吸衰竭好转，有助于明确诊断，无创通气可以改善夜间呼吸紊乱和白天的血气异常。

The Setting of Sipping Test Devices for Irradiated Fuel in Nuclear Power Plant

The sipping test devices are used to identify the defective fuel. The defective fuel can be identified by detecting the occurrence of the fission products that are entrained by the medium rising around the fuel rods. This project is the setting of the two kinds of the three sipping test devices to inspect the tightness of the irradiated fuel assembly from two units NPP （nuclear power plant）. The in-mast sipping shared by two units is used for qualitative tightness test of each fuel assembly during refueling operation above the reactor. The two poolside sipping is used for quantitatively confirming the diagnosis of the in-mast sipping and identifying the tightness of the fuel at the side of the fuel storage pools of each unit after refueling. The project was implemented by research, design manufacture and calibration of these three devices and completed successfully with serious quality assurance and quality control. The performance of these devices is well demonstrated.

Tests and numerical simulation of aerodynamic characteristics of airfoils for general aviation applications

This paper was to validate the effects of airfoil thickness ratio on the characteristics of a family of airfoils. Research was carried out in different ways. First,tests were conducted in the wind tunnel. And numerical simulation was performed on the basis of tests. Results from calculation were consistent with tests,indicating that numerical method could help evaluate characteristics of airfoils. Then the results were confirmed by compared with empirical data. The study also showed that the determining factor of lift is not only the thickness ratio,but the angle of attack,the relative camber and the camber line. The thickness ratio appears to have little effect on lift coefficient at zero angle of attack,since the angle of zero lift is largely determined by the airfoil camber. According to the research,numerical simulation can be used to determine the aerodynamic characteristics of airfoils in different environment such as in the dusty or humid air.

间接激发试验诊断运动诱发性支气管痉挛

运动诱发性支气管痉挛（exercise-induced bronchoconstriction，EIB）是由运动诱发的急性短暂的气道缩窄。在运动员中的发病率约3％～13％，诊断EIB需要肺功能下降的客观依据，间接气道激发试验是常用于诊断EIB的肺功能检查，本文就一些国际上认可的间接气道激发试验的方法及判断标准做一综述。

睡眠呼吸紊乱与呼吸衰竭及心力衰竭关系的研究

目的总结合并呼吸衰竭、左侧及右侧心功能不全（简称三衰）的睡眠呼吸紊乱（SDB）患者的临床特征。方法回顾性分析1994-2009年北京大学人民医院就诊的三衰合并SDB患者，分析其临床症状、体征及辅助检查特点和对过度通气试验及无创通气治疗的反应。结果入选患者29例，其中男13例，女16例，年龄13—87岁，平均（62±13）岁，平均体重指数为（34±4）ks／m2，其中初诊考虑睡眠呼吸暂停综合征者14例。主要症状为喘憋、颜面或下肢水肿、咳嗽、咳痰、打鼾、嗜睡、尿少及意识不清，共同的体征特点包括肥胖、上气道狭窄、口唇发绀、双肺底湿哕音、心界扩大、颜面或下肢水肿。29例中13例红细胞计数、血红蛋白及红细胞压积升高；26例行肺功能检查，FEV。／FVC占预计值％≥70％者14例，FEV，／FVC占预计值％〈70％者12例，其中6例50％≤FEV1占预计值％〈80％，6例30％≤FEV，占预计值％〈50％。给予正压通气治疗后临床症状明显缓解，血气pH值趋向正常，但部分患者PaCO2及HC03-水平仍较高。胸部影像学及超声检查结果提示肺淤血、胸腔积液、肺动脉高压、全心扩大及左心舒张功能不全，动态血压呈非杓型分布，以夜间血压升高为主，无创通气治疗可使血压明显下降，恢复杓型分布。11例行过度通气试验，脉氧饱和度及血气分析指标均较前改善，患者血气水平恢复正常。结论呼吸衰竭合并左侧及右侧心功能不全的患者中相当一部分与SDB有关。该类患者采用单纯吸氧和药物治疗效果差，无创通气可迅速缓解呼吸衰竭症状并有助于心功能的恢复。自主过度通气试验可作为筛查和鉴别诊断的有效手段。

功能性呼吸困难患者呼吸中枢负反馈机制的评价

目的探讨功能性呼吸困难患者呼吸中枢负反馈机制特点。方法临床诊断功能性呼吸困难12例，设立器质性疾病组和正常对照组各12例，分别检测各组过度通气试验前后屏气时间，数据行单因素方差分析。结果功能性呼吸困难组过度通气试验前、后屏气时间分别为：（62．67±20．4）s与（42．08±22．20）s，过度通气后屏气时间较过度通气前屏气时间缩短。器质性疾病组、正常对照组则过度通气后屏气时间较过度通气前屏气时间延长。功能性呼吸困难组与器质性疾病组、正常对照组相比存在显著差异，P〈0．001。结论器质性疾病组及正常对照组过度通气试验后屏气时间延长，符合呼吸中枢负反馈机制，功能性呼吸困难组过度通气试验后屏气时间较过度通气前缩短，不符合呼吸中枢负反馈机制，考虑患者组呼吸中枢负反馈机制减弱或缺失。

Numerical prediction of indoor airborne particle concentration in a test chamber with drift-flux model

The time-dependent variation of airborne particle concentration for different sizes in a test chamber was numerically predicted with drift-flux model. The performance of the drift-flux model for particle transport in different kinds of airflow fields was analyzed. The results show the drift-flux model can predict the transport of indoor fine particles reasonably well. When the air flow field varies slowly, the model can predict both the time-dependent variation ratio of the particle concentration and final stable concentration very well, and the difference for particles with different sizes can be also well predicted. When the air flow varies drastically, the accuracy of the model is decreased due to the neglect of the particles’ independent convective terms in the air flow.