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71.
Reversible and irreversible airway inflammation and fibrosis in mice exposed to inhaled ovalbumin 总被引:1,自引:0,他引:1
Objective and design: We examined the reversibility of several changes in the lungs and airways of mice immediately after exposure to ovalbumin aerosol and after a period of recovery breathing clean air.Methods: Mice were exposed for 1, 2, 4, 6, 8, or 10 weeks, with recovery in clean air for 1–3 weeks.Results: Airway collagen content, exhaled NO, airway mucous cell hyperplasia, and lung lavage inflammatory cell content increased upon exposure to ovalbumin aerosol. All parameters except airway fibrosis decreased partially or completely to control values with recovery in clean air.Conclusions: Airway mucous cell hypertrophy and hyperplasia appear to be completely reversible after recovery in clean air, while exhaled NO and airway inflammation appear to be mostly reversible, except for persistence of lymphocytes in the lung lavage fluid. Airway fibrosis appears to be reversible when mice are exposed to ovalbumin aerosol for periods of up to 4 weeks of exposure, but becomes irreversible after 6 or more weeks of exposure.Received 30 June 2004; returned for revision 24 September 2004; accepted by J. S. Skotnicki 13 October 2004 相似文献
72.
肝细胞肝癌肺转移灶FDG摄取的假阴性分析 总被引:1,自引:1,他引:0
目的评价18^F-FDG PET/CT探测原发性肝细胞肝癌(HCC)肺转移的价值,并分析肺转移灶FDG摄取假阴性的原因。方法32例经手术病理或临床随访证实为HCC肺转移的患者行18^F-FDG PET/CT检查,根据FDG摄取阳性或阴性分为2组:A组18例,肺转移灶表现为FDG摄取增高;B组14例,肺转移灶表现为无FDG摄取。结果32例HCC肺转移患者中,27例18^F-FDG PET/CT显像发现肝内高代谢病灶,12例伴发其他肝外转移,其中包括腹膜后淋巴结、肺门或纵隔淋巴结、骨骼转移。PET对最大径〈10mm的肺转移灶探测灵敏度为35.6%,对最大径≥10mm的肺转移灶探测灵敏度为63.6%,两者比较,差异有统计学意义(χ^2=4.712,P=0.03)。肺转移灶的FDG摄取变异较大,从无FDG摄取到少数病灶的显著FDG摄取,83.3%(25/30)摄取阳性的转移灶最大SUV(SUVmax)≤3。结论HCC肺转移灶FDG摄取假阴性率较高,除与病灶大小有关外,可能与原发病灶的病理特点有关。呼吸控制的薄层CT图像以及必要时增强CT对肺部小结节的检出非常重要,对CT显示小的肺结节病灶应严密随访。 相似文献
73.
目的探讨肺腺癌中VEGF-C、VEGF-D与微淋巴管密度MLVD(VEGFR-3)、微血管密度MVD (CD34)及淋巴结转移之间的关系。方法免疫组化检测48例肺腺癌组织中VEGF-C、VEGF-D、MLVD、MVD蛋白的表达。结果VEGF-C、VEGF-D蛋白阳性率分别为70.8%(34/48例)、58.3%(28/48例),肿瘤周边部位显著高于肿瘤中心部位,具有统计学意义,其表达与肿瘤分化程度无关,与肿瘤的TNM分期有关,Ⅲ~Ⅳ期显著高于Ⅰ~Ⅱ期。在VEGF-C蛋白阳性组,MVD高于阴性组(P=0.016),MLVD显著高于阴性组(P=0.006),淋巴结转移(P=0.042)增多;而VEGF-D蛋白阳性组与阴性组相比MVD无显著差异(P=0.943), MLVD高于阴性组(P〈0.01),淋巴结转移(P=0.012)增加。结论VEGF-C的表达与肺腺癌血管生成及淋巴管生成和淋巴结转移关系密切,而VEGF-D的表达只与淋巴管生成和淋巴结转移关系密切,与血管生成无关。 相似文献
74.
穹窿体是真核细胞中的核糖核蛋白颗粒,由肺耐药蛋白、穹窿体多聚腺苷二磷酸聚合酶、端粒酶相关蛋白和穹窿体RNA构成,其主要成分为肺耐药蛋白。肺耐药蛋白是介导肿瘤多药耐药的蛋白之一,可能与肿瘤的治疗效果和临床预后相关。穹窿体可能通过介导药物转运或者信号转导引起肿瘤的多药耐药。文章介绍了穹窿体的结构、成分及其介导多药耐药机制研究的新进展。 相似文献
75.
238例复治肺结核病人耐药状况分析 总被引:1,自引:0,他引:1
目的 了解复治肺结核病人形成原因和耐药状况,分析结核病控制策略的效果。方法 分析1999年湖北省耐药监测入选238例复治涂阳培阳病例既往病史和耐药状况;药敏试验采用比例法,培养基中药物浓度分别为S 4μg/ml、H 0.2μg/ml、R 40μg/ml和E 2μg/ml;结果 总耐药率为44.5%,耐多药率为21.8%,在综合医院、乡镇卫生院和结防专业机构治疗造成的耐药率和耐多药率(含H和R)分别为56.4%、31.3%、46.3%和30.8%、15.0%、20.8%。结论 治疗不规范是导致耐药率和耐多药率升高的原因,建议加强结核病人归口、化疗和全程督导管理,进一步完善结核病控制策略,减少复治病例和耐药的产生。 相似文献
76.
Olivier Chataigner Elie Fadel Bedrettin Yildizeli Abdallah Achir Sacha Mussot Dominique Fabre Olaf Mercier Philippe G. Dartevelle 《European journal of cardio-thoracic surgery》2008,33(5):837-843
Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival. 相似文献
77.
肺腺癌经支气管肺转移的CT表现 总被引:1,自引:0,他引:1
目的认识肺腺癌经支气管播散肺转移的CT表现和规律。方法回顾性分析15例经病理证实为腺癌或细支气管肺泡癌经支气管肺转移患者的CT表现,重点关注病变的发展特点。结果15例肺癌患者在CT上原发病灶均为实变型肺癌,在同侧或对侧肺内出现多发性、与支气管分布有明确相关的病灶,胸膜不受累。在初诊的CT上表现为小叶中心性结节5例、树芽征7例、腺泡结节2例、磨玻璃影10例和实变13例,其中5例仅有小叶中心结节(单一型),10例为多种形态病变共存(复合型),曾全部被误诊为结核或炎症,经抗结核或抗炎治疗无效。在平均4个月的CT随访中,单一型转移者进展缓慢,结节融合形成边界相对清晰的实变影;初诊为复合型的病变恶化较快。结论肺腺癌经支气管转移的CT表现有一定规律,但诊断仍须结合临床及实验室检查,以区别于结核和炎性反应。 相似文献
78.
79.
目的初步探讨减瘤手术在晚期肺癌治疗方面的实用价值。方法选择2006年1月至2008年1月笔者所在医院收治的的中晚期肺癌患者20例,采用减瘤手术治疗。选择同时期15例剖胸探查肺肿物活检患者作为对照组。研究分析两组患者术后生存质量及生存时间的差异。结果减瘤组患者生存质量较好率为40.0%,对照组为20.0%,两组间比较差异有统计学意义(χ^2=7.21,P〈0.05)。生存质量评分减瘤组为(35.3±8.2)分,对照组为(27.9±7.1)分,两组间比较差异有统计学意义(t=6.59,P〈0.05)。平均生存时间减瘤组患者为11.6个月,对照组为10.3个月,两组间比较,差异无统计学意义(t=2.41,P〉0.05)。结论减瘤手术可改善中晚期或已有远处转移的肺癌患者的生存质量。 相似文献
80.
Caroline Van De Wauwer Arne P. Neyrinck Nele Geudens Filip R. Rega Geert M. Verleden Erik Verbeken Toni E. Lerut Dirk E.M. Van Raemdonck 《European journal of cardio-thoracic surgery》2007,31(6):1125-1133
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion. 相似文献