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51.
We studied functional and immunohistochemical characteristics of cultured rat microglia. Unstimulated microglia did not proliferate. Microglia stimulated with LCM (L929 conditioned medium: colony stimulating factor-1) had proliferative activity and increased acid phosphatase activity. LPS (lipopolysaccharide) and IFN gamma (interferon-gamma) but did not affect proliferative activity. Immunohistochemically, RCA-1 lectin and GS-1 lectin, which react to beta-D-galactose and alpha-D-galactose respectively, strongly reacted to the cytoplasm and membrane of unstimulated microglia. After stimulation with LCM, microglia elongated processes and decreased response to these lectins. On the other hand, microglia stimulated with LCM showed increased reactivity to monoclonal antibody of vimentin. Microglia stimulated with LPS had round shape and had response to these lectins and vimentin. Microglia stimulated with IFN gamma had adhesive activity and weakly stained with these lectins but not with vimentin. ED-1 (monoclonal antibody of rat monocytes/macrophages) reacted to unstimulated and stimulated microglia. In flow cytometry, unstimulated microglia expressed OX-18 (MHC class I) and W3/25 (CD4) antigen. After stimulation with IFN gamma, microglia were induced to express these antigens. CD4 antigen is a marker of helper/inducer T cells and thought to be a receptor of HIV. The results that microglia had CD4 antigen which was further induced with IFN gamma are important to investigate infection of the CNS with HIV. OX-6 (Ia) antigen was induced with IFN gamma. This indicates that the microglia plays a central role in the CNS immune reaction. These characteristics of cultured rat microglia provide useful informations to investigate the pathogenesis of the CNS disorders.  相似文献   
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Introduction  

This paper presents the results of a study on the psychometric properties of an authorized Spanish version of the McMaster Family Assessment Device, a self-report measure of family functioning.  相似文献   
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Introduction  

Although ependymoma is the third most common pediatric brain tumor, we know little about the genetic/epigenetic basis of its initiation, maintenance, or progression. This is due in part to the heterogeneity of the disease, as well as the small sample size of the cohorts analyzed in most studies.  相似文献   
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A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography (PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant potential of esophageal submucosal tumors.  相似文献   
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Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present, was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin (all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%) and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases, preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic injury after preoperative chemotherapy was regimen-specific. Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida.  相似文献   
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