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51.
Although the association between asbestos exposure and malignant mesothelioma is indisputable, controversy continues regarding the relative contribution of the various types of asbestos fibers to the development of mesothelioma. We examined the types of asbestos fibers recovered from lung parenchyma in more than 90 cases of malignant mesothelioma from the United States, using an analytical scanning electron microscope. Almost half of the patients were former asbestos insulators or shipyard workers. The fibers were recovered from lung tissues obtained at autopsy or surgical resection by means of a sodium hypochlorite digestion procedure. Amosite absestos was identified in 81% of the cases and accounted for 58% of all fibers 5 μm or greater in length. Tremolite/actinolite/anthophyllite were identified in 55% of the cases and accounted for 10% of all fiber types. Chrysotile was identified in 21% of the cases and accounted for 3% of fibers exceeding 5 μm in length. Crocidolite was found in 16% of the cases and accounted for 3% of fibers exceeding 5 μm in length. Nonasbestos mineral fibers (commonly found in the lungs of the general population) were observed in 71% of the cases and accounted for 25% of all fibers 5 μm or greater in length. The findings in this study are at odds with the assertion that crocidolite asbestos is responsible for most mesotheliomas in the United States. © 1993 Wiley-Liss, Inc.  相似文献   
52.
本文用显微分光光度计对39例手术切除的不同组织学类型的人体肺癌标本癌细胞核的DNA含量进行了测量。其中高、中、低分化的鳞癌分别为3、6和5例;高、中、低分化的腺癌分别为3、5和5例;未分化癌大细胞型和小细胞型各为3例和6例。结果发现各类型肺癌的DNA含量均有统计学上的差异(P<0.01)。各DNA含量直方图的峰值部位及分布范围亦不同。从而提示了根据DNA含量的不同,可能有助于肺癌组织学类型及其分化程度的判别:而DNA含量直方图对肺癌类型的判别亦可能是有益的。  相似文献   
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用酶联亲合组化法对46例肺肿瘤细胞进行了雌激素受体(ER)和孕激素受体(PR)检测。同时测定14例肺瘤肿患者血清雌二醇(E_2)浓度。结果表明:肺肿瘤 ER 阳性率为36.9%,PR 阳性率为13.0%。阳性率与性别、病理类型及血浆 E_2浓度无关。认为肺癌的发生发展可能与雌激素有依赖关系,提示内分泌疗法可能会成为原发肺肿瘤的一种治疗手段。另用 ABC 法对上述46例肺肿瘤中的29例进行了花生凝集素受体(PNA-R)和麦胚凝集素受体(WGA-R)的检测,PNA-R 在腺癌大都为顶浆型分布,鳞癌和透明细胞癌则多为胞膜型分布。结果提示 PNA-R 是肺癌分化过程中的一种标志,对肺癌分型、预后判断有一定协助作用。同时将29例肺肿瘤 PNA-R 与 ER 状况作对比研究,探讨了二者之间的相关性及可能的发生机制。  相似文献   
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The integrin 51 seems to be the most relevant receptor of tumor cells for binding to fibronectin. Although numerous studies suggest a role of tumor cell fibronectin interaction in tumor metastasis, differential integrin expression on tumor cells has, however, not been correlated with metastatic capabilities. We addressed this question by transfection of the integrin 51 cDNA into HT-29 human colon carcinoma cells which led to de novo expression of functional integrin 51. Similar to other reports, expression of the integrin 51 in HT-29 tumor cells exerted an inhibitory action on cell proliferation as indicated in our study by formation of fewer colonies in soft agar. The tumor growth inhibitory property of the integrin 51 was also shown by reduction of subcutaneous xenograft growth in nude mice to approximately 50% of that of control transfectants. For the first time, we found that several clones of integrin 5 subunit transfectants displayed dramatically reduced formation of lung colonies and cutaneous metastasis after intravenous injec-tion into nude mice. While most animals inoculated with control transfectant cells formed macroscopically visible lung colonies ranging from 12.6 ± 2.6 to 22.0 ± 6.6 (mean colony number ± SEM), mice inoculated with HT-29 cell clones expressing the integrin a5b1 were almost completely free of lung colonies (ranging from 0.0 ± 0 to 0.2 ± 0.1). Our results imply that integrin 51 expression inhibits circulating tumor cells in pursuing late steps of the metastatic process as represented by the artificial metastasis (lung colonisation) model. © Rapid Science Ltd.  相似文献   
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Synergistic interactions between cytokines, chemokines and adhesion molecules may facilitate the selective recruitment of eosinophils into sites of allergic inflammation. Ovalbumin-sensitized IL5TG mice responded to antigen challenge with robust airway eosinophilia 24 and 72 hr post-exposure. Adhesion molecule expression and functional responsiveness of immune cells derived from IL5TG mice to various inflammatory mediators were evaluated. IL5TG-derived eosinophils, but not neutrophils, expressed higher levels of CD49d and CD11b relative to WT. Functional responsiveness to eotaxin was increased in IL5TG eosinophils as demonstrated by a 10× increase in its potency in producing actin polymerization and 3× increase in CD11b upregulation relative to WT. These data are consistent with increased CCR3 expression on IL5TG eosinophils. Responsiveness of eosinophils to LTB4 or MIP-1 was similar between WT and IL-5TG mice. These data provide evidence of synergy between eosinophil-specific cytokines and chemokines that may promote accumulation of this cell type under conditions of allergic inflammation in vivo.  相似文献   
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Objective

Interstitial lung disease (ILD) is the most severe complication of idiopathic inflammatory myositis (IIM), resulting in significant increase in morbidity and mortality and for which the best treatment remains controversial. We conducted a meta-analysis to evaluate the efficacy of therapies used for the management of IIM-related ILD.

Methods

Studies were selected from MEDLINE up to July 2017. Two investigators independently extracted data on study design, patient characteristics, clinical features, treatment, follow-up and outcomes. Global survival rates and objectively confirmed lung function improvements were extracted as the main outcome for rapidly progressive IIM-related ILD (RP-ILD) and chronic forms of ILD (C-ILD), respectively, and pooled using the weighted mean proportion with fixed or random-effects models in case of significant heterogeneity (I2?>?50%).

Results

Twenty-seven studies encompassing 553 patients (male: 30.5%, age: 53.5?±?5.5?years) were included in the meta-analysis. Globally, retrieved studies were of limited methodological quality (no controlled studies and only 2 prospective studies). Dermatomyositis (40%) and anti-tRNA synthetase syndrome (45%) were the most represented IIM subtypes. In C-ILD, functional improvement rates were 89.2% (95%CI 82.5–93.6; 7 studies, n?=?124) for corticosteroids alone, 80.7% (95%CI 49.6–94; 6 studies, n?=?38) for cyclosporine A, 64.1% (95%CI 46.3–78.7; 4 studies, n?=?32) for azathioprine, 86.2% (95%CI 61.5–96; 2 studies, n?=?23) for tacrolimus, 56.4% (95%CI 44–68.0; 8 studies, n?=?71) for cyclophosphamide, and 76.6% (95%CI 50.4–96.0; 2 studies, n?=?20) for rituximab. In RP-ILD, survival rates at 3?months were 51.7% (95%CI 24.2–78.1; 2 studies, n?=?11) for corticosteroids alone, 69.2% (95%CI 55.0–80.5; 8 studies, n?=?146) for cyclosporine A and 72.4% (95%CI 6.4–99.0, 2 studies, n?=?16) for cyclophosphamide.

Conclusion

Despite aggressive immunosuppressive therapies, the short-term mortality of RP-ILD remains high. While immunosuppressive therapies are associated with significant functional improvements in most patients with C-ILD, substantial uncertainty remains about the best treatment strategy in the absence of good quality evidence.  相似文献   
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