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91.
In vivo expression of major histocompatibility complex molecules on oligodendrocytes and neurons during viral infection 下载免费PDF全文
Demyelination in multiple sclerosis and in animal models is associated with infiltrating CD8+ and CD4+ T cells. Although oligodendrocytes and axons are damaged in these diseases, the roles T cells play in the demyelination process are not completely understood. Antigen-specific CD8+ T cell lysis of target cells is dependent on interactions between the T cell receptor and major histocompatibility complex (MHC) class I-peptide complexes on the target cell. In the normal central nervous system, expression of MHC molecules is very low but often increases during inflammation. We set out to precisely define which central nervous system cells express MHC molecules in vivo during infection with a strain of murine hepatitis virus that causes a chronic, inflammatory demyelinating disease. Using double immunofluorescence labeling, we show that during acute infection with murine hepatitis virus, MHC class I is expressed in vivo by oligodendrocytes, neurons, microglia, and endothelia, and MHC class II is expressed only by microglia. These data indicate that oligodendrocytes and neurons have the potential to present antigen to T cells and thus be damaged by direct antigen-specific interactions with CD8+ T lymphocytes. 相似文献
92.
B McKenzie-Green LS Giddings L Buttle K Tahana 《International journal of dental hygiene》2009,7(1):31-38
Abstract: Objectives: Little is known about older persons’ perceptions of oral health and oral health care. The purpose of this study was to explore the viewpoint of older adults’ regarding their oral health care practices. Methods: A qualitative interpretive methodology was employed comprising three analytic levels: coding of data into concepts, analysis of concepts into themes, followed by an in‐depth analysis of relationships within concepts and between themes. In‐depth individual interviews were conducted with 19 participants aged 65 to 87 years. Results: Older people’s decision to access oral health care involves complex and personally meaningful strategies. A dental visit surfaces hopes and fears based on past and present experiences. Mouth and teeth are not merely objects of dental care; they represent a person’s social and relational self. Age‐related changes challenge the relational self as represented in societal ideal images of youth and perfection (the perfect smile). This study highlights older peoples’ resilience and determination when faced with the dilemmas in accessing oral health care – it costs, personally as well as financially. Contrary to the assumption that older peoples’ oral health status is related to neglect, rather for many, it is the result of the intersection of their history with technological advances. Conclusions: These findings challenge oral health care practitioners to be sensitive to the contexts affecting their older client’s oral health care status. They do not ‘just go’ to the dentist; they bring with them their past dental experiences and their hopes for the future. It matters how one is treated at this vulnerable time. 相似文献
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Mandeep Singh MRCSEd Jovina LS See FRCSEd Maria C Aquino MD Lennard SY Thean FRCSEd Paul TK Chew FRCSEd 《Clinical & experimental ophthalmology》2009,37(4):345-351
Background: The aim of this work was to image trabeculectomy blebs using spectral domain optical coherence tomography (SDOCT).
Methods: In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results: Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P = 0.02), scleral flap (34.9% vs. 90.7%, P < 0.0001), subflap space (20.9% vs . 72.1%, P < 0.0001) and ostium (9.3% vs. 88.4%, P < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P = 0.005).
Conclusions: SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium. 相似文献
Methods: In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results: Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P = 0.02), scleral flap (34.9% vs. 90.7%, P < 0.0001), subflap space (20.9% vs . 72.1%, P < 0.0001) and ostium (9.3% vs. 88.4%, P < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P = 0.005).
Conclusions: SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium. 相似文献
97.
贺国丽 《国外医学:妇产科学分册》2009,(2):147-147
根据沙利度胺和拓扑特肯的活性机制和具抗血管生成的特性,本研究比较了沙利度胺联合拓扑特肯与拓扑特肯单用在复发的上皮性卵巢、输卵管、腹膜癌的疗效。
此项历时4年的多中心的前瞻性随机2期研究得到明尼苏达大学妇女癌症中心的协助。人选者具有下列条件之一:①在以铂类和紫杉醇为基础的初始化疗后未控。 相似文献
98.
Physicians need more information about the causes and the long-term consequences of amenorrhea due to exercise and weight loss before they can give proper advice to women who exercise strenuously. 相似文献
99.
Mucinous differentiation in prostatic adenocarcinoma. 总被引:1,自引:0,他引:1
Morphologic and histochemical analysis was performed on 33 carcinomas with mucin-secreting areas that were identified among 100 carcinomas from radical prostatectomy specimens. The most common mucin-secreting pattern was Gleason grade 3, which usually showed distinctive luminal distention. The "colloid carcinoma" pattern with mucinous lakes was the only histologic pattern that was unique to mucinous areas. Its frequent association with cribriform Gleason grade 4 carcinoma suggests that it is a variant of grade 4 cancer, whose deviant appearance is a consequence of mucus hypersecretion. Collagenous stromal micronodules, found in 13 cases, are a previously undescribed and distinctive pattern thought to be a stromal reaction to contact with acidic extraluminal mucin. In grade 3 carcinoma, glands that secreted into the stroma rather than the gland lumen accounted for the stromal mucin, which appeared to lead to micronodule formation. In the grade 4 "colloid cancer" pattern, collagenous micronodules sometimes completely obliterated mucinous lakes, isolating residual cribriform glands in a "pseudo-grade 3" pattern. Lectin histochemical staining showed similar sialated and/or sulfated acidic mucin in all cases. Immunohistochemical staining showed downregulation of several differentiation antigens accompanying the alteration to mucinous differentiation. 相似文献
100.
Ways DK; Qin W; Riddle RS; Garris TD; Bennett TE; Steelman LS; McCubrey JA 《Blood》1991,78(10):2633-2641
FD/PMA is a subclone of the interleukin-3 (IL-3)-dependent, FDC-P1 cell line, which proliferates in response to either 12-O- tetradecanoylphorbol-13 acetate (PMA) or IL-3. While several endogenous substrates were phosphorylated in response to protein kinase C (PKC) activation in FDC-P1, phospholipid-dependent phosphorylation in the FD/PMA grown in PMA was not observed. Basal, phosphatidylserine- independent, and diolein-independent phosphorylation of cytosolic substrates with molecular weights of 17, 52, 57, and 105 Kd were enhanced in FD/PMA cells grown in PMA as compared with FDC-P1 cells cultured in IL-3. Phosphorylation of a 105-Kd substrate was enhanced in the particulate fraction of FD/PMA cells maintained in PMA. The 17-Kd substrate in FD/PMA cells comigrated with a substrate phosphorylated in a PKC-dependent manner in FDC-P1 cells. Phosphorylation of the 52- and 57-Kd substrates, but not of the 17-Kd substrate, was inhibited by H-7 and staurosporine. A portion of the PMA-induced cytosolic kinase activity coeluted with PKC on diethyl aminoethyl chromatography. While FD/PMA cells cultured in PMA contained negligible PKC-dependent phosphorylation of endogenous substrates or histone, alpha and epsilon PKC isoforms were detected by Western blot analysis. PKC phosphotransferase activity was observed in FD/PMA cells grown in PMA when peptides corresponding to residues 720 to 737 of PKC-epsilon or residues 4 to 14 of myelin basic protein were used as substrates. These data indicate that maintenance of FD/PMA cells in PMA stimulates proliferation and markedly alters PKC substrate specificity. Generation of at least two phospholipid-independent kinases occurs in PMA-treated cells. 相似文献