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91.
Purpose: To investigate changes in the production of tissue inhibitor of metalloproteinase type 1 (TIMP-1) by human retinal pigment epithelial (RPE) cells following argon laser exposure. Methods: Human cultured ARPE19 cells were exposed to argon green laser at four different energy levels ranging from 60mW to 360mW. After laser exposure, the culture media were sampled at 0, 24, 72 and 144 hours for TIMP-1 concentration produced by the RPE cells. The levels of TIMP-1 in the cells treated with different laser energy levels were compared with a control group not exposed to laser application. Immunocytochemistry for proliferating cell nuclear antigen (PCNA) was performed to detect any adverse effects on the RPE cells caused by laser exposure. Results: Immediately after laser exposure, the concentration of TIMP-1 was not detectable. At 24 hours after laser exposure, the concentration of TIMP-1 increased significantly in RPE cells treated with 120mW and 240mW at 24 hours (P=0.006 and P=0.001 respectively) comp  相似文献   
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Glioblastoma multiforme (GBM), the most malignant type of glioma, is the most common primary brainneoplasm. Although comprehensive therapeutic measures are applied, the prognosis of GBM remains dismal with a median post-treatment survival of less than one year.Modern molecular genetics has demonstrated thatabnormal alterations of tumor suppressor genes (TSGs) and oncogenes are the major mechanisms responsible for the initiation and progression of this malignant tumor.Identifying of related…  相似文献   
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Objective : To reveal the effectiveness and safety of adding a single slit valve serially to the ventriculoperitoneal shunt system in order to reverse overdrainage. Materials and Methods : The study is a retrospective review of clinical experience in a regional hospital (Tuen Mun Hospital, Hong Kong). A series of 10 cases are reported. All cases showed evidence of cerebrospinal fluid overdrainage after a ventriculoperitoneal shunt procedure. The advantages and disadvantages of other treatment options are also reviewed. Results : The symptoms of all six patients who presented symptomatically subsided or improved after the procedure. Nine of the 10 patients had radiological improvement in their postoperative computed tomography scan. No procedure‐related complication occurred. Conclusion : The early results of such a treatment option appeared safe and rewarding. However, longer term follow up and more experience is needed before the treatment’s efficacy can be proved definitely.   相似文献   
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Plasma cell neoplasia in humans generally occurs as multiple myeloma, an incurable form of cancer. Tumors with marked similarity can be induced in mice by a variety of agents, including chemicals, silicone, and oncogene-containing retroviruses, suggesting the use of murine tumors as an informative model to study plasma cell disease. Herein, we have focused on the role of insulin-like growth factor I receptor (IGF-IR) signaling in the development of plasma cell disease. The insulin receptor substrate 2/phosphatidylinositol 3'-kinase/p70S6K pathway was found to be either constitutively or IGF-I-dependently activated in all plasma cell tumors. Biological relevance was demonstrated in that plasma cell lines with up-regulated IGF-IR expression levels exhibited mitogenic responses to IGF-I. More importantly, expression of a dominant-negative mutant of IGF-IR in these lines strongly suppressed tumorigenesis in vivo. Taken together, these results demonstrate that up-regulation and activation of IGF-IR and the downstream signaling pathway involving insulin receptor substrate 2, phosphatidylinositol 3'-kinase, and p70S6K may play an important role in the development of a broad spectrum of plasma cell tumors.  相似文献   
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巫山淫羊藿的化学研究   总被引:8,自引:0,他引:8  
从小檗科Berberidaceae淫羊藿属Epimedium植物巫山淫羊藿Epimedium wushanense T.S.Ying的地上部分中分得两种黄酮甙单体,经理化性质鉴定及紫外、红外、质谱、氢谱、碳谱等光谱分析,确定甙Ⅰ是新化合物,命名为巫山淫羊藿甙(wushanicariin)。甙Ⅱ是已知化合物淫羊藿甙(icariin),系首次从该种植物中分离。  相似文献   
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