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91.
熵代表无序的水平,作者使用通气的熵变(ECV)指示肺通气的不均匀性,ECV定义为当前泡潮气量趋近于零时每摩尔被吸入气体从不均匀通气到均匀通气的熵变的极限。本文从熵的基本公式民地出ECV的计算方程。用几个数学模型肺将ECV同其他7个洗出指标进行了比较。8个指标中,只有ECV仅取决于通气分布,其他7个指标不仅取决于通气分布,还同潮气量和死腔的大小有关。这影响了它们评价肺通气不均匀性的效果,ECV的另一 相似文献
92.
肺结核病人红细胞免疫功能及T淋巴细胞亚群的变化 总被引:1,自引:0,他引:1
①目的探讨红细胞免疫功能及T淋巴细胞亚群变化与肺结核的关系。②方法对44例肺结核病人和44例健康人的红细胞免疫功能、血清循环免疫复合物、T淋巴细胞亚群、NK细胞水平的变化进行了检测,并与对照组比较。③结果肺结核病人红细胞C3b受体花环率(E-C3bRR),CD4,CD4/CD8,NK细胞水平明显降低,CD8水平明显升高,与对照组相比,差异均有极显著意义(t=9.76~22.24,P均<0.01);复治组较初治组变化更明显(t=4.27~15.32,P均<0.01)。E-C3bRR与CD4,CD4/CD8,NK细胞水平呈正相关(r=0.2692~0.5479,P<0.05,0.01),与CD8呈显著负相关(r=-0.374,P<0.01)。④结论红细胞免疫功能、T淋巴细胞亚群及NK细胞的异常与肺结核的发病及病情变化有一定关系。 相似文献
93.
松龄血脉康抑制肺动脉高压的实验研究 总被引:1,自引:0,他引:1
为观察松龄血脉康胶囊对肺动脉高压大鼠肺动脉压的影响,取100只健康Wistar大鼠,其中60只背部注射野百合碱monocrotaline,MCT80mg/kg复制出肺动脉高压模型。再将其分为两组,各30只,其中一组以标准饲料喂养,另一组加用松龄血脉康胶囊1.5g·kg-1·d-1。其余40只健康大鼠做为正常对照组,在实验当天、7天、14天、21天、28天、35天从各组中随机抽取5只行右心导管测肺动脉压。结果:注射MCT后肺高压组28天时达高峰,但加用松龄血脉康组上升幅度明显小于未用药组。结论:松龄血脉康有显著抑制大鼠肺动脉高压发展的作用 相似文献
94.
完全性肺静脉异位引流的手术治疗经验 总被引:15,自引:1,他引:14
为评估影响完全性肺静脉异位引流(TAPVD)手术纠治的因素,本组纳入了28例在中度低温体外循环和15例在深低温停循环下手术纠治者。结果手术死亡4例,死亡率9.3%。随访32例,2例肺静脉回流梗阻分别于术后5个月和2年3个月死亡。结论认为,TAPVD必须早期手术防止肺血管阻塞性病变;术后定期随访;改进手术方法,防止心房内补片粘连所致肺静脉回流梗阻。 相似文献
95.
1962~1986年25年间,经尸检病理确诊的29例新生儿肺出血,以早产儿和低出生体重儿为主,生后一周内发病者27例。本组20例有窒息史,口鼻有血性分泌物流出者17例。本文描述了新生儿肺出血的临床表现和病理特征,以及对新生儿肺出血的病因作了讨论。 相似文献
96.
Dennis J. Murphy 《Drug development research》1994,32(4):237-246
The known effects of drugs from a variety of pharmacologic/therapeutic classes on the respiratory system and worldwide regulatory requirements support the need for conducting respiratory evaluations in safety pharmacology. The objective of these studies is to evaluate the potential for drugs to cause secondary pharmacologic or toxicologic effects that influence respiratory function. Changes in respiratory function can result either from alterations in the pumping apparatus that controls the pattern of pulmonary ventilation or from changes in the mechanical properties of the lung that determine the transpulmonary pressures (work) required for lung inflation and deflation. Defects in the pumping apparatus are classified as hypo- or hyperventilation syndromes and are evaluated by examining ventilatory parameters in a conscious animal model. The ventilatory parameters include respiratory rate, tidal volume, minute volume, peak (or mean) inspiratory flow, peak (or mean) expiratory flow, and fractional inspiratory time. Defects in mechanical properties of the lung are classified as obstructive or restrictive disorders and can be evaluated in animal models by performing flow-volume and pressure-volume maneuvers, respectively. The parameters used to detect airway obstruction include peak expiratory flow, forced expiratory flow at 25 and 75% of forced vital capacity, and a timed forced expiratory volume, while the parameters used to detect lung restriction include total lung capacity, inspiratory capacity, functional residual capacity, and compliance. Measurement of dynamic lung resistance and compliance, obtained continuously during tidal breathing, is an alternative method for evaluating obstructive and restrictive disorders, respectively, and is used when the response to drug treatment is expected to be immediate (within minutes post-dose). The species used in the safety pharmacology studies conducted in our laboratory are the same as those used in toxicology studies since pharmacokinetic and toxicologic/pathologic data are available in these species. These data can be used to help select test measurement intervals and doses and to aid in the interpretation of functional change. The techniques and procedures for measuring respiratory function parameters are well established in guinea pigs, rats, and dogs. 相似文献
97.
Abstract Several methods have been used to predict successful weaning and extubation among chronic obstructive pulmonary disease (COPD) patients. The objective of this study is to determine whether carbon dioxide recruitment threshold (PCO2 RT) can be used as adjunct to conventional weaning parameters to predict early weaning and successful extubation. Twelve COPD patients who were ready to be extubated based on conventional weaning parameters were divided into group A ( n = 7) and group B ( n = 5). Group A were those patients with better weaning parameters and hence a higher probability of successful extubation as compared to group B. Carbon dioxide apnoeic threshold (PCO2 AT) was obtained by hyperventilating the patient using an increment of two breaths per min until apnoea occurs. At this point, the PCO2 AT or the PaCO2 during said apnoeic period was recorded. A dead space of 150 cc is then added to the circuit until the patient starts to breathe as evidenced by the sensitivity trigger indicator. The PCO2 obtained at this period is termed PCO2 RT. After weaning for 30 min on a T-tube, another arterial blood gas is determined and this is called the PCO2 SB or the CO2 level after 30 min on spontaneous breathing. If the PCO2 SB-PCO2 RT difference is high with a sensitivity of 85.71% and specificity of 100% vs sensitivity of 57.14% and specificity of 60% using the conventional weaning parameters. Thus an increase in PCO2 SB at 30 min T-tube is indicative of impending respiratory pump failure and that other causes of failure to wean must be investigated. 相似文献
98.
目的探讨低能量氦-氖激先局部加穴位照射对肺结核空洞的治疗作用机理。方法91例初治Ⅲ型肺结核(肺部有空洞)随机分为实验组46例,对照组45例,均用6个月短程化疗方案.实验组加氦-氖激光局部、双肺俞穴位照射治疗3个疗程,观察空洞闭合及痰菌阴转情况,以X2检验分析组间治疗结果的差异.结果实验组治疗2、3个月空洞闭合分别为58.3%、70.8%;对照组为354%、479%,二者均有显著性差异(P<0.05),实验组痰菌阴转、肺部病灶吸收、临床症状改善均高于对照组。结论低能量氦-氖激光局部加双肺俞穴位照射,可加速肺结核空洞的闭合及临床症状的改善 相似文献
99.
T. Urano Y. Shibayama K. Fukunishi K. Nariyama N. Ohsawa 《Virchows Archiv : an international journal of pathology》1996,427(6):607-612
We examined the effect of interruption of pulmonary arterial flow and inadequate ventilation on the development of pulmonary infarction in rats. Pulmonary arterial flow was blocked by the injection of agar into the inferior vena cava and inadequate ventilation was produced by obstructing the left main bronchus with a polypropylene tip. Histological and angiographic examination of the lung demonstrated that: pulmonary artery embolism alone does not induce pulmonary infarction; obstruction of a bronchus does not induce significant changes, but that pulmonary infarction develops when pulmonary artery embolism and obstruction of a bronchus occur simultaneously. It has been thought that pulmonary infarction is caused by acute obstruction of a pulmonary artery, however, the alveolar walls are supplied with oxygen by both the pulmonary circulation and by ventilation. Interruption of pulmonary arterial flow alone is probably not sufficient to induce pulmonary infarction, which is probably caused by deficiency of oxygen supply to the alveolar walls by a synergy between interruption of pulmonary arterial flow and inadequate ventilation. 相似文献
100.
101例尿毒症相关性肺水肿的特殊护理措施 总被引:2,自引:0,他引:2
目的 探讨尿毒症相关性肺水肿的特殊护理措施。方法 对尿毒症相关性肺水肿的护理除常规护理措施外,应做到以下几点特殊护理:①密切观察血压、血氧饱和度、近期尿量变化;②有效控制血压;③采取不同的透析方式适时适量透析超滤、加强透析中的护理;④改善全身营养状况,防止肺部感染;⑤牢记护理程序体位-吸氧-血管扩张药-血液透析;⑥严格控制入量。结果 101例病人中抢救成功84例,死亡13例,自动出院3例。结论 采取治疗和特殊护理对抢救尿毒症相关性肺水肿患者有较好效果。 相似文献