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71.
72.
Granular cell tumours rarely involve the lower respiratory tract. We report eight cases surgically resected at our institution. There were four females and four males, aged between 18 to 56 years (mean 40). One tumour associated with a peripheral lung adenocarcinoma was asymptomatic. The other lesions presented with obstructive pneumonitis (3 cases), haemoptysis (2), dyspnea (1) or cough (1). These tumours were tracheal (1) or bronchial (6) and one case was located in the lung parenchyma. Four cases were multicentric with associated lesions located in a bronchus (2), the oesophagus (1) or a mediastinal lymph node (1). All tumours, with the largest diameter ranging from 0.5–4.5 cm, were histologically invasive. The tumours were positive for S-100 protein, neuron specific enolase, KP1 (CD68) and vimentin. No tumour expressed desmin, keratin or p53 oncoprotein. Our study demonstrates that, in spite of marked anatomical and clinical polymorphism, the rare granular cell tumours of the lower respiratory tract have a constant histological appearance. Our observations confirm that large tumours (> 8–10 mm) usually extend beyond the tracheo-bronchial cartilages and, therefore, only surgical treatment may avoid recurrence. 相似文献
73.
Obstructive and restrictive ventilatory impairment in polyvinylchloride fabrication workers 总被引:1,自引:0,他引:1
P Ernst L De Guire B Armstrong G Thériault 《American journal of industrial medicine》1988,14(3):273-279
Responses to a standardized respiratory symptom questionnaire, spirometry, and cross-shift decreases in lung function between 70 current employees of a polyvinylchloride (PVC) fabrication plant and a control group consisting of 48 men employed in a vegetable packing plant were compared. FEV1/FVC was significantly lower in the PVC workers. Cross-shift drops in Vmax75 of 15% or more were also more prevalent in the exposed group (p = .01). When examining the association between months of work within the exposed workforce and spirometric indices of airway obstruction, no relationship could be demonstrated. However, an inverse dose-response relationship was seen between level of FVC and duration of employment, suggesting a restrictive impairment. While the specific exposures have not been identified, it appears that employment in PVC fabrication may be associated with both obstructive and restrictive ventilatory effects. 相似文献
74.
Jan E. Zejda Thomas S. Hurst Ernest M. Barber Charles Rhodes James A. Dosman 《American journal of industrial medicine》1993,23(5):743-750
A cross-sectional survey on respiratory health in swine producers showed that 30% of 301 examined men usually used a dust mask when working inside a barn. They did not differ significantly from dust mask nonusers in respect to respiratory symptoms and lung function. This analysis was undertaken to determine whether the respiratory health of dust mask users was associated with reasons why they had started individual respiratory protection. The subjects were recontacted in order to identify those who started using a mask to deliberately prevent symptoms (42 men) and those who started protection because of pre-existing respiratory symptoms (44 men). Not unexpectedly, betweengroup comparisons of respiratory symptoms and lung function suggest that swine producers who wear dust masks for preventive purposes have better respiratory health than those who wear dust masks because of symptoms or those who do not use individual respiratory protection. The individual reasons for starting dust mask usage should be examined among potential determinants of the outcomes of prospective studies which can then provide more valid assessment of the effect of individual respiratory protection. © 1993 Wiley-Liss, Inc. 相似文献
75.
76.
心包内处理肺血管及心房部分切除治疗中心型肺癌 总被引:1,自引:0,他引:1
1987年5月至1993年12月对16例较晚期肺癌采用心包内处理肺血管及心房部分切除的方法作了全肺切除术,肿瘤均为中心型。CT扫描显示隆突下或主肺动脉窗淋巴结肿大者占50%,术中见肺动脉,肺静脉均受累者8例,肺静脉受累者6例,2例作左心室部分切除,15例恢复良好,1例术中大出血致心脏停搏,复苏后并发脑水肿昏迷死亡。我们认为,心包内处理肺血管全肺切除提高了手术切除率,且手术过程较安全可靠,作者对这种 相似文献
77.
Protective effects of cyclophosphamide, cyclosporin A and FK506 against antigen-induced lung eosinophilia in guinea-pigs.
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A close association has been recognized between activated T cells and eosinophils in asthma, albeit circumstantial. The present study attempted to investigate this relationship in an animal model of lung eosinophilia using the new generation of T cell-selective immunosuppressants, cyclosporin A and FK506, compared with the myelotoxic immunosuppressive agent cyclophosphamide. Antigen challenge of ovalbumin-sensitized guinea-pigs resulted in a lung eosinophilia which was assessed by bronchoalveolar lavage. All three agents caused a marked suppression of lung eosinophilia at 24 h post-challenge when the compounds were administered at the time of sensitization but not when administered for 3 days before lavage. However, the lung eosinophilia at 72 h post-challenge was reduced significantly by FK506 and by cyclophosphamide, but not by cyclosporin A, when the drugs were administered for 3 days, before lavage. These results strongly suggest the involvement of T cells in antigen-induced late phase (72 h) eosinophilia in guinea-pigs but not at 24 h. The effects of cyclophosphamide were always associated with a reduction in circulating white cell counts, whereas cyclosporin A and FK506 showed no myelotoxic properties. These results suggest the potential therapeutic use of selective, non-cytotoxic immunosuppressive agents in asthma. 相似文献
78.
应用单链构象多态性分析多聚酶链反应EB染色法(PCR-SSCP-EB)对40例肺癌组织标本的P53基因序列5~8外显子突变进行分析,同时应用PCR方法检测上述标本及18例肺良性疾病组织标本中HPV16、18型DNA相关序列,旨在分析二者在肺鳞癌发病中的作用及相互关系,并就肺鳞癌与P53基因结构和功能异常的关系进行初步探讨。 相似文献
79.
肺内小病灶CT表现及其病理基础的研究:附76例分析 总被引:9,自引:0,他引:9
本文对76例肺内小病灶(直径≤3cm)病例进行了CT-病理对照研究。结果表明,短毛刺征,深分叶征、棘状突起征、空泡征、血管集束征,胸膜凹陷征等对于诊断周围型小肺癌有重要临床价值;而尖角征、局限性胸膜肥厚粘连对诊断良性病灶有意义。本文重点讨论了血管集束征的定义,CT表现及病理基础;并就有争议的胸膜凹陷征提出一些粗浅的看法。旨在提高肺内小病灶良恶性诊断的准确率 相似文献
80.
糖尿病大鼠肺病理改变及同期肾脏病理变化对比 总被引:3,自引:0,他引:3
目的:观察糖尿病(DM)大鼠肺组织改变及与同期肾脏变化的关系.方法:链脲菌素腹腔注射制作糖尿病大鼠模型,4周后胶原、网状纤维染色及透射电镜方法观察糖尿病大鼠肺组织基底膜病理改变,同期观察肾脏改变.结果:DM大鼠4周后肺组织病理改变为毛细血管基底膜及Ⅱ型肺泡上皮细胞基底膜不同程度的增厚及肺间质胶原成分等细胞外基质的增多,与同期糖尿病肾脏病变相平行.结论:DM大鼠4周后肺组织与糖尿病肾病相似,主要表现为微血管病变. 相似文献