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991.
The case of a 49-year-old man with peripheral T-cell lymphoma arising in Behçet disease (BD) is reported. A diagnosis of incomplete BD was made, and the patient was treated with immunosuppressive agents for 9 months. A left perirenal mass emerged, and a computed tomography-guided needle biopsy of the tumor revealed the infiltration of small- and medium-sized lymphoma cells.The cells were positive for CD3, CD8, CD45RO, CD43, granzyme B, and T-cell intracellular antigen-1.A diagnosis of non-Hodgkin’s lymphoma (diffuse medium, T-cell) was made.A left orbital mass also appeared. Standard combination chemotherapy diminished the perirenal and orbital lesions.Lymphoma cell infiltration in the esophagus was detected after chemotherapy, and the patient died of massive bleeding from the gastrointestinal tract. Non-Hodgkin’s lymphoma is rarely associated with BD, and only 7 cases have been reported in the literature.We have summarized the published case reports of malignant lymphoma arising in BD.To our knowledge, this case report is the first to describe cytotoxic T-cell lymphoma arising in Behçet disease.  相似文献   
992.
Hepatocellular carcinoma often recurs even after curative resection. Although some encouraging data showing improvements in recurrence-free times have been reported with the use of intraarterial 131I-lipiodol infusion, retinoids, interferon, or immunotherapy after hepatectomy, there is no consensus regarding standard adjuvant therapy for resectable hepatocellular carcinoma. A novel target agent, sorafenib, which has recently become a standard of care for advanced disease, may also be promising in an adjuvant setting to prevent early recurrence after curative surgery. In future trials, it will be important to identify appropriate target populations for each type of adjuvant approach; that is, an agent with definitive antitumor activity for high-risk patients, and one that shows chemoprevention for low-risk patients.  相似文献   
993.
994.
Since the prevention of early chronic pancreatitis (ECP) into chronic pancreatitis might be critical for the reduction of pancreatic cancer, we tried to clarify the pathophysiology of ECP patients, focusing on ECP patients without alcoholic chronic pancreatitis. 27 ECP patients without alcoholic chronic pancreatitis and 33 patients with functional dyspepsia with pancreatic enzyme abnormalities (FD-P) were enrolled in this study. Diagnosis of ECP was made when imaging findings showed the presence of more than 2 out of 7 endoscopic ultrasound features. Duodenal degranulated eosinophils and glucagon-like peptide 1 producing cells were estimated by immunostaining. There were no significant differences in characteristics and psychogenic factors between ECP and FD-P patients. Interestingly, endoscopic ultrasound score in ECP patients significantly improved, albeit clinical symptoms in ECP patients showed no improvement at one year follow up. The extent of migration of duodenal degranulated eosinophils in FD-P patients was significantly higher compared to that in ECP patients. The levels of elastase-1 and trypsin in ECP patients with improved endoscopic ultrasound features were significantly reduced by the treatment. Further studies will be needed to clarify whether clinical symptoms and endoscopic ultrasound features in ECP patients without alcoholic chronic pancreatitis were improved in longer follow up study.  相似文献   
995.
In rheumatoid arthritis (RA), osteoclastic bone resorption causes structural joint damage as well as periarticular and systemic bone loss. Periarticular bone loss is one of the earliest indices of RA, often preceding the onset of clinical symptoms via largely unknown mechanisms. Excessive osteoclastogenesis induced by receptor activator of NF-κB ligand (RANKL) expressed by synovial fibroblasts causes joint erosion, whereas the role of RANKL expressed by lymphocytes in various types of bone damage has yet to be elucidated. In the bone marrow of arthritic mice, we found an increase in the number of RANKL-expressing plasma cells, which displayed an ability to induce osteoclastogenesis in vitro. Genetic ablation of RANKL in B-lineage cells resulted in amelioration of periarticular bone loss, but not of articular erosion or systemic bone loss, in autoimmune arthritis. We also show conclusive evidence for the critical contribution of synovial fibroblast RANKL to joint erosion in collagen-induced arthritis on the arthritogenic DBA/1J background. This study highlights the importance of plasma-cell RANKL in periarticular bone loss in arthritis and provides mechanistic insight into the early manifestation of bone lesion induced by autoimmunity.  相似文献   
996.
997.
Cribriform-morular variant of papillary carcinoma is a distinctive histological variant of thyroid cancer, characterized by intermingled cribriform, follicular, papillary, trabecular, and morular architecture. These tumors are known to be associated with familial adenomatous polyposis (FAP), but are also encountered in non-FAP patients. The authors report on ultrastructural and genetic studies of 3 patients with this type of carcinoma-associated FAP. There were numerous microfilaments approximately 100?nm long at the nuclear clearing area of the morular regions. Two of the 3 patients showed germline APC mutations, and 1 had so somatic APC mutation. Both mutations were in previously unreported regions. The study provides new information for understanding the development of this rare tumor.  相似文献   
998.
999.
We previously discovered a splice variant of choline acetyltransferase (ChAT) mRNA, and designated the variant protein pChAT because of its preferential expression in peripheral neuronal structures. In this study, we examined the immunohistochemical localization of pChAT in rat cochlea and compared the distribution pattern to those of common ChAT (cChAT) and acetylcholinesterase. Some neuronal cell bodies and fibers in the spiral ganglia showed immunoreactivity for pChAT, predominantly the small spiral ganglion cells, indicating outer hair cell type II neurons. In contrast, cChAT- and acetylcholinesterase-positive structures were localized to fibers and not apparent in ganglion cells. After ablation of the cochlear nuclei, many pChAT-positive cochlear nerve fibers became clearly visible, whereas fibers immunopositive for cChAT and acetylcholine esterase disappeared. These results suggested that pChAT and cChAT are localized in different systems of the rat cochlea; pChAT in the afferent and cChAT in the efferent structures.  相似文献   
1000.
Aquaporins are water channel proteins which enable rapid water movement across the plasma membrane. Aquaporin-5 (AQP5) is the major aquaporin and is expressed on the apical membrane of salivary gland acinar cells. We examined the effects of repeated administration of pilocarpine, a clinically useful stimulant for salivary fluid secretion, and isoproterenol (IPR), a stimulant for salivary protein secretion, on the abundance of AQP5 protein in rat salivary glands by immunofluorescence microscopy and semi-quantitative immunoblotting. Unexpectedly AQP5 was decreased in pilocarpine-administered salivary glands, in which fluid secretion must be highly stimulated, implying that AQP5 might not be required for fluid secretion at least in pilocarpine-administered state. The abundance of AQP5, on the other hand, was found to be significantly increased in IPR-administered submandibular and parotid glands. To address the possible mechanism of the elevation of AQP5 abundance in IPR-administered animals, changes of AQP5 level in fasting animals, in which the exocytotic events are reduced, were examined. AQP5 was found to be decreased in fasting animals as expected. These results suggested that the elevation of cAMP and/or frequent exocytotic events could increase AQP5 protein. AQP5 expression seems to be easily changed by salivary stimulants, although these changes do not always reflect the ability in salivary fluid secretion.  相似文献   
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