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101.
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   
102.
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   
103.
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 (PCO2RT) 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 (PCO2AT) was obtained by hyperventilating the patient using an increment of two breaths per min until apnoea occurs. At this point, the PCO2AT 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 PCO2RT. After weaning for 30 min on a T-tube, another arterial blood gas is determined and this is called the PCO2SB or the CO2 level after 30 min on spontaneous breathing. If the PCO2SB-PCO2RT 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 PCO2SB 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   
104.
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   
105.
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   
106.
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   
107.
Hypoxiaisadirectfactorcausinghypoxicpul monaryhypertension (HPH) .hypoxiainduciblefac tor 1α (HIF 1α)isfoundtobethemostcrucialfactorsofarwhichmediatesthecellularresponsetohypoxi a[1] .OurpreviousstudyrevealedthatoverexpressionofHIF 1andendothelin 1(ET 1…  相似文献   
108.
慢性阻塞性肺疾病前驱性呼吸衰竭患者呼吸驱动的改变   总被引:15,自引:4,他引:11  
目的探讨慢性阻塞性肺疾病(COPD)和COPD前驱性呼吸衰竭(前驱呼衰)患者中枢呼吸驱动的改变;评价界定COPD前驱性呼吸衰竭的临床意义.方法试验对象为COPD前驱性呼吸衰竭、COPD尚未达前驱性呼吸衰竭的患者和健康对照者各30名.所有受试者均进行如下参数的测定:动脉血气分析;常规肺功能,主要以第1秒用力呼气容积(FEV1)占预计值的百分比(FEV1%)来评价;中枢呼吸驱动水平,以0.1 s口腔阻断压(P0.1)、校正中枢呼吸驱动(以每分通气量来校正,即P0.1/MV)和吸气阻抗P0.1/VT/Ti)等来评价.结果P0.1和P0.1/MV在COPD前驱呼衰组明显高于正常对照组和未达前驱呼衰组,P0.1/VT/Ti在COPD前驱呼衰组和未达前驱呼衰组明显高于正常对照组(P=0.002);P0.1,P0.1/MV,P0.1/VT/Ti与PaO2,FEV1%呈显著负相关(rs=-0.769,-0.495,-0.543;-0.747,-0.480,-0.526,P均<0.01);与PaCO2呈显著正相关(rs=0.270,0.312,0.369,P分别为<0.05,<0.01,<0.01).结论COPD前驱呼衰患者呼吸储备能力减低,呼吸效率下降;P0.1,P0.1/MV,P0.1/VT/Ti等参数在推断患者神经-肌力输出水平与呼吸衰竭发生阈值方面具有较大的意义.当COPD进展至前驱呼衰阶段,从血气分析、肺功能检查到呼吸驱动水平都发生了显著的改变,从而提示界定此阶段具有一定的临床意义.  相似文献   
109.
目的 总结我市结核病控制项目实施效果和经验。方法 根据全市各县(区)上报的结核病报表和有关总结材料进行分析。结果 在项目实施期间发现涂阳病人7522例,治愈了7303例,涂阳病人登记率从1993年的8.2/10万提高到2001年的39.4/10万,初、复治涂阳病人治愈率从1992年的80.0%和81.8%提高到2001年的98.9%和96.2%。结论 我市结核病控制项目实施效果显,项目所取得的成功经验和技术策略对今后结核病控制可持续发展有着重要的指导作用。  相似文献   
110.
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198)  相似文献   
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