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51.
52.
In previous studied with computed tomography (CT) prior to and during general anaesthesia, we found that densities developed in dependent parts of the lungs immediately after induction of anaesthesia in all examined patients. It was suggested that the densities were atelectases created by compression of lung tissue but an alternative explanation could be accumulation of extravascular fluid in the lung tissue and/or in the pleural space. In the present study the nature of the densities was analysed in further detail. Injections of contrast medium into the pleural space revealed that the densities were located in the lung tissue and not in the pleural space. By injecting contrast medium intravenously and repeating the CT scanning over a 2-min period the passage of contrast through the major vessels and the lung densities could be studied. The transit time of the contrast medium was of the same magnitude in the densities and the major lung vessels. This indicates that there were no regions with an increased amount of extravascular fluid to delay the contrast passage. These findings oppose the idea of fluid accumulation as the cause of the densities, while atelectasis remains the most plausible explanation.  相似文献   
53.
实验采用猪背部创伤模型,观察重组的碱性成纤维细胞生长因子(bFGF)对创伤修复的作用。在无菌条件下用特制打孔器在猪背部切割皮肤,形成2.5cm2的园型创面。将150个创面分成5组,分别以bFGF(60u/cm2创面),bFGF((60u/cm2创面)加SD-Ag、SD-Ag、生理盐水以及不治疗等方法处理,每间隔一天换药一次。实验结果表明,bFGF具有显著促进肉芽组织生长、加速创面再上皮化率以及增加创面愈合组织抗张力强度等作用。FGF显著促修复效应的确切机制尚不完全清楚,可能包括直接与间接效应两方面。  相似文献   
54.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination.  相似文献   
55.
We present herein the rare case of a young man who was found to have a solitary tumor in the right upper lobe of his lung by a routine chest X-ray. The tumor was removed by thoracoscopic surgery, and pathological examinations confirmed the diagnosis of a primary lymphangioma of the lung. A brief review of the available literature on this extremely rare type of benign tumor follows the case report.  相似文献   
56.
蚓激酶生物活性检测方法的研究   总被引:8,自引:1,他引:7  
郝苏丽  沈佳 《中国药事》1996,10(6):403-405
本文采用组织纤溶酶原激活剂(TPA)─纤维蛋白平板法测定蚓激酶的生物活性。该法操作简便,易于观察,重现性好。  相似文献   
57.
Clusterlike Headache as a First Sign of Brain Metastases of Lung Cancer   总被引:1,自引:0,他引:1  
Dr.  J. Tajti  MD  PhD ; Dr.  K. Sas  MD ; Dr.  D. Szok  MD ; Dr.  E. Vörös  MD ; Dr.  L. Vécsei  MD  DSc 《Headache》1996,36(4):259-260
We report on a patient with clusterlike headache and multiple brain metastases of lung cancer. Initially, cluster headache was suggested clinically by characteristic symptoms without any focal central nervous system signs. However, magnetic resonance imaging demonstrated multiple brain metastases. It is possible that tumor necrosis factor may have played a role in initiating the clusterlike headache.  相似文献   
58.
Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.  相似文献   
59.
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE.  相似文献   
60.
组织扩张术皮肤胶原的代谢改变   总被引:4,自引:0,他引:4  
李江  鲁开化 《医学争鸣》1998,19(3):307-309
目的:研究常规扩张(ITE)和持续快速扩张(CTE)对皮肤胶原代谢的影响。方法用白色小家猪制作组织扩张术动物模型,用Gordeladze法测定血清和扩张组织的羟脯氨酸(HP)含量,藻酸盐印模材膜片法测量标记区面积;光镜测量真皮厚度。结果:ITE组血清HP含量升高,0.8倍,CTE组升高1.2倍,ITE和CTE组皮肤含量与正常皮肤相同,组织中HP总量均明显升高,持续扩张皮瓣组(CTEF)术后4wk皮  相似文献   
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