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51.
The antimicrobial susceptibility test was necessary for the eradication therapy of Helicobacter pylori infections. This is because, clarithromycin resistant strains has became an increasing problem. In this study, we used the antimicrobial susceptibility test which was compare with the agar gradient method, Etest, and broth microdilution method (dry plate) with 4 antimicrobial agents. The results strongly suggested that broth microdilution method was the best method in order to test the antimicrobial susceptibility of H. pylori. On the other hand, 393 H. pylori stains isolated during 1994-1998 from clinical patients were tested for antimicrobial susceptibility test to amoxicillin, clarithromycin, metronidazole, and minomycin. There were no resistant strains to amoxicillin and minomycin. But clarithromycin and Metronidazole resistant strains were recognized in 85 (22.0%) and 36 (21.7%) strains.  相似文献   
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Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway.  相似文献   
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T helper 17 (Th17) cells that produce interleukin (IL)-17A and IL-17F have been found to participate in the development of bronchial asthma and bleomycin-induced pulmonary fibrosis. However, whether they play a causative role in the airway remodeling observed in these respiratory diseases remains unclear. Because fibrocytes are involved in tissue repair and fibrosis and are presumably precursors of lung fibroblasts and myofibroblasts, we examined the effects of IL-17A/F on fibrocyte functions. Both IL-17A and IL-17F enhanced fibrocytes’ α-smooth muscle actin expression. Priming fibrocytes with IL-17A enhanced their CD40-mediated IL-6 production, whereas IL-17F-priming increased the CD40-mediated mRNA expression of collagen I, vascular endothelial growth factor, and angiogenin. CD4+ T cells co-cultured with fibrocytes produced IL-17A, which was inhibited by blocking CD40 and CD40 ligand interactions. These findings suggest that cooperative interactions between fibrocytes and Th17 cells play an important role via CD40- and IL-17A/F-mediated signaling for collagen and proangiogenic factor production, which may lead to the extracellular matrix deposition and neovascularization seen in airway remodeling.  相似文献   
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Annals of Nuclear Medicine - Albumin–globulin ratio (AGR), which is calculated by dividing serum albumin by serum globulin, is considered as a cancer-related inflammation biomarker. Although...  相似文献   
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OBJECTIVE: To investigate the involvement of osteopontin (OPN) in bone destruction in a murine experimental arthritis model of collagen-induced arthritis (CIA). METHODS: The expression of OPN was examined at both the messenger RNA (mRNA) and protein levels in various arthritic lesions in mice with CIA by in situ hybridization and immunohistochemistry, respectively. In addition, the expression of alpha(v)beta3 integrin, a receptor for OPN, the ligation of which is thought to be essential for bone resorption by osteoclasts, was examined by immunohistochemistry. Plasma concentrations of OPN were measured at different time points in the course of CIA by enzyme-linked immunosorbent assay. RESULTS: OPN mRNA was detected mainly at sites of bone erosion in arthritic lesions, where activated osteoclasts were present; OPN protein was also detected at sites of bone erosion. In the arthritic synovium, OPN was predominantly expressed in the synovial lining layer, but not in lymphoid aggregates. In addition, alpha(v)beta3 integrin was detected coincident with OPN at sites of bone erosion (bone-pannus junction). Plasma OPN levels were markedly elevated at the time points that corresponded to arthritis flares, and higher levels were maintained during the progression of arthritis. CONCLUSION: OPN may mediate bone resorption by osteoclasts in arthritis through ligation with its receptor, alpha(v)beta3 integrin. OPN may be a useful therapeutic target molecule in the prevention of bone destruction in arthritis.  相似文献   
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Acute parvovirus B19 infection mimicking chronic fatigue syndrome   总被引:2,自引:0,他引:2  
A Japanese woman developed prolonged fatigue, neck and shoulder pain, headache, pyrexia, insomnia, anorexia, lymphadenopathy, and diarrhea for two months. She had experienced various stressors before these symptoms developed. Serological test demonstrated that she had acute parvovirus B19 infection. Major depressive disorder was also diagnosed by a psychiatrist. Her symptoms disappeared after administration of selective serotonin reuptake inhibitors and oriental herbs, although human parvovirus B19 viral genome has been present in her serum for nine months. These findings suggest that parvovirus B19 causes clinical features similar to those of chronic fatigue syndrome in cases who have prior life stressors.  相似文献   
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