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711.
Bombyx mandarina nucleopolyhedrovirus (BomaNPV) is a variant of Bombyx mori nucleopolyhedrovirus (BmNPV). BomaNPV S1 strain has been reported to be significantly less virulent than the BmNPV T3 strain via the oral infection route in B. mori larvae, but other features of S1 including budded virus (BV) infectivity and virus propagation in cultured cells are still unknown. In this study, we compared BV infectivity of S1 and T3 in B. mori larvae and cultured cells. Larval bioassays by intrahemocoelic BV injection revealed that the median lethal dose of S1’s BV was approximately three times lower than that of T3. In addition, S1 produced more BVs and occlusion bodies (OBs) in the hemolymph of B. mori larvae compared with T3. Furthermore, we observed that the locomotion was enhanced earlier and the median lethal time was shorter in S1-infected larvae compared with those in T3-infected larvae. Western blot analysis of S1- and T3-infected BmN cells revealed that expression of late and very late gene products in S1-infected cells was higher than that in T3-infected cells. Collectively, these results clearly show that S1’s BV infectivity is higher than that of T3 in both B. mori larvae and cultured cells, although S1’s OBs are much less infectious to B. mori larvae than T3’s.  相似文献   
712.
We report a rare case of inverted Schneiderian papilloma causing exceedingly high serum levels of carcinoembryonic antigen (CEA) and squamous cell carcinoma-associated antigen (SCC). A 74-year-old man presented with a 6-month history of a productive cough, bloody sputa, and dyspnea. Chest computed tomography showed massive infiltration in the lower lobe with multiple focal soft tissue densities. Blood biochemical analysis revealed a serum CEA level of 107.0 ng/ml (normal <5.0 ng/ml), and an SCC level of 373.0 ng/ml (normal <1.5 ng/ml). Squamous papilloma was diagnosed by histological examination of a bronchoscopic biopsy specimen. To alleviate the patient's symptoms and refine the diagnosis, we performed a right lower lobectomy. The lower lobe of the lung was filled with mucinous sputa and very fragile papillary tumors of various sizes. Microscopic examination revealed papillary growth of stratified epithelial cells with massive mucin production. No nuclear abnormality or invasion of the basal membrane of the tumor cells was observed. Postoperatively, the patient's symptoms resolved quickly, and the serum levels of CEA and SCC decreased to 6.4 ng/ml and 1.7 ng/ml, respectively, within 3 months.  相似文献   
713.
714.
Angiogenesis in primary central nervous system lymphoma (PCNSL)   总被引:3,自引:0,他引:3  
Angiogenesis and angiogenic growth factors have a major role in the pathogenesis of malignancies. However, very little is known about the clinical and histopathological relevance of angiogenesis in primary central nervous system lymphoma (PCNSL). We investigated that expression of vascular endothelial growth factor (VEGF) of the lymphoma cells and microvessel density (MVD) were examined in 19 patients with PCNSL. Additionally, the presence of the blood–brain barrier (BBB) was examined using immunohistochemistry and the electron microscopy. MVD was significantly higher in nine cases with VEGF immunoreactivity (VEGF+) than in ten cases with negative immunoreactivity for VEGF (VEGF−) (P < 0.001). VEGF expression was significantly associated with a longer survival (P < 0.005). BBB markers were negative in angiogenic vessels of VEGF+. BBB markers were identified in vessels surrounding tumor cells and tight junctions were also preserved in the capillary endothelium surrounding tumor cells in VEGF−. Angiogenesis is associated with VEGF expression and an absent BBB in the vessels of PCNSL. The BBB may be preserved in lesions with lymphoma cell infiltration, especially in VEGF− PCNSL. VEGF may have a prognostic effect in PCNSL.  相似文献   
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