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101.
We propose a haphazard branching theory to support the concept of bronchopulmonary malinosculations, and we apply this theory to classify congenital bronchopulmonary vascular malformation (BPVM) based on the anatomical results we have found. Between January 1990 and December 1997, a total of 22 pediatric patients (10 male and 12 female), aged 2 days to 14 years (median, 19.6 months), with congenital BPVM were enrolled in this retrospective study. Study modalities include the clinical features and plain chest films (n = 22) plus at least two of the following: echocardiography (n = 13), barium esophagraphy (n = 2), bronchoscopy (n = 4), contrast bronchography (n = 8), high-resolution direct coronal CT (n = 1) and electron beam or ultrafast CT (n = 1) of the chest, MRI (n = 10), MRA (n = 1), contrast cineangiocardiography (n = 9), surgery (n = 11), or autopsy (n = 2). The salient clinical features were recurrent lung infections in 14 patients, acute respiratory distress in 13, associated cardiovascular malformations in 8, dextroversion in 7, congestive heart failure in 7, dextrocardia in 4, and complex congenital heart diseases in 4. There were abnormal openings (malinosculations) of the pulmonary airway in 20 patients: to an artery in 12, to a vein in 8, and to the lung parenchyma in 9. These 22 patients with congenital BPVM can be classified into bronchial malinosculation (10 cases), arterial malinosculation (2 cases), and bronchoarterial malinosculation (10 cases). Congenital BPVM can be classified in terms of bronchopulmonary malinosculation based upon a haphazard branching theory, in which abnormal communications between two independent systems (primitive foregut system and aortic-pulmonary arch system) occurred coincidentally rather than causally.  相似文献   
102.
目的:评价变应性哮喘患儿血清嗜酸性粒细胞阳离子蛋白(S-ECP)水平改变及其意义。方法:测定25例哮喘发作期患儿糖皮质激素吸入治疗12周前后,及20例未予糖皮质激素吸入治疗的哮喘缓解期患儿S-ECP水平,并对发作期患儿S-ECP水平变化与血嗜酸性粒细胞计数(B-EOS)、肺功能一秒用力呼气量(FEV1)、一秒用力呼气量比用力肺活量(FEV1/FVC)及症状评分的关系作相关性分析。结果:哮喘发作组治疗后S-ECP水平较治疗前显著降低,与对照组(健康儿童10名)比较差异无显著性;哮喘缓解组S-ECP水平明显高于发作组治疗后,但明显低于发作组治疗前。哮喘发作组治疗前S-ECP水平变化与B-EOS无相关性,与FEV1、FEV1/FVC呈负相关,与症状评分呈正相关。结论:监测S-ECP水平可作为评价哮喘气道炎症程度、病情预后和指导抗炎治疗的有效指标。  相似文献   
103.
目的 探讨碱性成纤维细胞生长因子 (b FGF)在低氧性肺动脉高压发病中的作用。方法 采用酶联免疫吸附法对具有低氧性肺动脉高压的肺心病患者 2 1例、无低氧性肺动脉高压的慢性阻塞性肺疾病 (COPD)患者 2 3例和 2 4例正常人血清 b FGF水平进行检测 ,以多普勒超声心动仪测定肺心病和 COPD患者的平均肺动脉压 (m PAP)。结果 肺心病组 m PAP水平 (33.33± 7.0 3m m Hg)明显高于 COPD组 (13.13± 2 .34mm Hg) ,P<0 .0 0 1;肺心病组血清 b FGF水平 (6 9.84± 16 .2 9pg/m l)明显高于 COPD组 (43.94± 7.5 7pg/ml)和正常对照组(44 .6 4± 6 .31pg/m l) ,P<0 .0 0 1;肺心病血清 b FGF水平与 m PAP之间呈明显正相关 ,r=0 .730 ,P<0 .0 0 1。结论慢性肺心病患者血清 b FGF水平明显升高 ,可能与其慢性低氧性肺动脉高压的形成有一定的关系。  相似文献   
104.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage.  相似文献   
105.
烹调油烟致大小鼠肺癌的实验研究   总被引:1,自引:0,他引:1  
[目的]了解烹调油烟(cooking oil fumes,COF)的动物致癌性。[方法]采用动式染毒法给Balb/c小鼠(雌雄各半)吸入COF浓度为9.09、20.65、38.85mg/m^3,染毒1次/1~2d,30min/次,共150次,计8个月;SD大鼠(雌雄各半)吸入COF浓度为6、88、15.06、35.33mg/m^3,染毒1次/2d,30min/次,共191次,计12.5个月。分别制备COF慢性中毒动物模型;两实验均设空白对照组,吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb/c小鼠实验组肺癌总发生率为18、95%(29/153),低、中、高浓度组肺癌发生率分别为15.09%、20、00%和22.00%,与对照组差异均有显著性。但低、中、高三组间差异无显著性(P〉0.05);COF诱发SD大鼠肺癌总发生率为9、10%(9/99),低、中、高浓度组肺癌发生率分别为6.45%、8.57%、12.12%,高浓度组肺癌发生率高于对照组(P〈0.05)。各性别组间肺癌发生率的差别无显著性(P〉0.05)。[结论]COF可以诱导Balb/c小鼠和SD大鼠肺癌,诱发的肺癌主要为肺腺癌(小鼠28/29,大鼠7/9),余为小细胞肺癌。  相似文献   
106.
107.
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation.  相似文献   
108.
During 1983 and 1984, 1305 patients underwent 1,400 pulmonary artery (PA) catheterizations. Successful placement was achieved in 1397 (99.6%) of 1,403 attempts. The catheters were inserted via the right internal jugular vein on 1364 occasions. The median duration of monitoring was 28 h with a range from 3 to 220 h. Central venous puncture complications included carotid artery puncture in 67 instances (4.8%) and pneumothorax in one patient. Insertion of the catheters was associated with supraventricular arrhythmias on 11 occasions, ventricular arrhythmias on 930 (66.4%), right bundle branch block on two and a total heart block on one occasion. Eighteen (2.3%) of the 794 cultured catheter tips were positive. An in situ time of more than 72 h was associated with a significantly higher percentage (7.2%) of positive tip cultures compared with an in situ time of less than 72 h (P less than 0.01). Repeated PA catheterization was not associated with significantly more complications than the initial catheterization. The results show that monitoring with a PA catheter in cardiac surgical patients is associated with a low incidence of morbidity.  相似文献   
109.
脑出血后血肿周围组织可发生继发性损伤。研究表明,细胞凋亡在脑出血后继发性损伤中起着重要作用。抑制细胞凋亡可显著改善脑出血后的神经功能缺损。  相似文献   
110.
目的分析与产后出血相关的因素,提出合理的防治措施。方法以12600例产妇为研究对象,将胎儿娩出后2h内出血量达到或超过400ml,或胎儿娩出后24h出血量达到或超过500ml定义为产后出血,测量产后出血量。通过非条件Logistic回归分析,筛选出与产后出血相关的主要危险因素,对比出血发生率的变化。结果在12600例分娩产妇中,符合产后出血的有198例,单因素分析中有10个因素有统计学意义。结论加强孕前宜教和孕期管理,提高助产技术,规范缩官素在产前的应用,降低了产后出血的发生。  相似文献   
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