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排序方式: 共有4244条查询结果,搜索用时 15 毫秒
11.
Mariko Hosono H. Kobayashi Ryota Fujimoto Kazushige Tsutsui Yoshihiko Kotoura Tadao Tsuboyama Hikaru Hayashi Takashi Nakamura Junji Konishi 《Skeletal radiology》1997,26(9):525-528
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with
plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast
T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense
rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have
this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant
disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. 相似文献
12.
Behcet's disease (BD) is characterized by recurrent oral aphthae, skin lesions, eye lesions, and genital ulceration. To determine the pathogenesis of BD, we performed histological and immunohistochemical studies of these mucocutaneous lesions, an assay of neutrophil activity, and HLA typing. Dense dermal or subcutaneous infiltrations of polymorphonuclear cells (PMN) without leukocytoclastic vasculitis were found in 28 of 57 lesions. Immunohistochemically, deposits of C3 on the vessels were found in 12 of 31 lesions. Deposits of immunoglobulin were not found except for one of IgM. C3 deposits and PMN infiltrations were significantly related (p<0.05). PMN activity by polarization was enhanced; however, the results did not show a significant relationship with the PMN infiltrations or the C3 deposits. The incidence of HLA-B51 was significantly high in BD, but no significant relationship was found between HLA-B51 and the results of other examinations. These results suggest that the pathogenesis of BD lesions differs from that of collagen diseases and that C3 deposits on the vessels may play an important role in the development of mucocutaneous lesions where PMN have mainly infiltrated. 相似文献
13.
Koichi Tanaka Kazue Ozawa Satoshi Teramukai Yasutsugu Takada Hiroto Egawa Satoshi Kaihara Yasuhiro Fujimoto Yasuhiro Ogura Mureo Kasahara Masako Ono Hiroshi Sato Kenji Takai Masanori Fukushima Nagahiro Minato 《Liver transplantation》2006,12(5):792-800
The primed status of T cells is markedly different among liver transplant recipients, due to a lifetime of antigen exposure and reduced thymopoiesis by aging, and diseases. This study aims to characterize the preoperative immunological status of CD8+ T cell subpopulations and relate it to the outcome for liver transplant recipients. We classified 112 liver transplant recipients into 5 groups, based on hierarchical clustering of the CD8+CD45 isoform proportion of T cells. In Groups I and II (pediatric), the naive T cell proportion was more than 50%. In adult recipients, Group III was characterized by a naive T cell proportion of 50%, Group IV had the greatest effector/memory T cells (EM), and Group V had the greatest proportion of effector T cells. In Groups IV and V, the effector T cell proportion was considerably higher, and was accompanied by marked downregulation of the CD27+CD28+ subsets and upregulation of interferon gamma (IFN)-gamma, tumor necrosis factor-alpha, and perforin expression. Group V recipients tended to be complicated postoperatively, with a significantly reduced survival rate (1 yr, 66.8%) and markedly reduced Eastern Cooperative Oncology Group performance status. 相似文献
14.
Masako Tsunematsu Taketo Yamaji Daisuke Kozutsumi Rika Murakami Shigeki Kimura Kohsuke Kino 《Allergology international》2007,56(4):465-472
BACKGROUND: We are developing an immunotherapeutic peptide, Cry-consensus peptide, for Japanese cedar pollinosis. Cry-consensus peptide is a recombinant polypeptide containing six major human T-cell epitopes derived from both Cry j 1 and Cry j 2, two major allergens of Japanese cedar pollen. We examined the effect of Cry-consensus peptide on an allergic rhinitis model in B10.S mice, which have one common T-cell epitope in the Cry-consensus peptide. METHODS: B10.S mice were sensitized with Cry j 1/alum, then the Cry-consensus peptide was administered subcutaneously once a week for 5 weeks from the last sensitization. Histamine was dropped in both nostrils (10 microL per nostril) of each mouse on the day before continuous intranasal instillation of Cry j 1. Soon after the final challenge with Cry j 1, the mice were observed for 5 minutes for the resulting number of sneezes. In addition, serum levels of Cry j 1-specific IgE and IgG2a antibody, eosinophil infiltration in nasal tissue, and Cry j 1-specific cytokine production from splenocytes were evaluated. RESULTS: Cry-consensus peptide markedly inhibited Cry j 1-induced sneezes, eosinophil infiltration, and eosinophil peroxidase (EPO) activity in nasal tissue. Cry-consensus peptide inhibited the production of anti-Cry j 1 IgE (Th2-mediated) and significantly enhanced anti-Cry j 1 IgG2a (Th1-mediated). In cytokine production from splenocytes, Cry-consensus peptide significantly decreased in IL-4/IFN-gamma and IL-5/IFN-gamma ratios. CONCLUSIONS: It was concluded that Cry-consensus peptide effectively controlled allergic responses, which results from shifting from a Th2-dominated to a Th1-dominated immune response. 相似文献
15.
Pharmacologic preconditioning effects: Prostaglandin E1 induces heat-shock proteins immediately after ischemia/reperfusion of the mouse liver 总被引:1,自引:0,他引:1
Ken-ichi Matsuo M.D. Shinji Togo M.D. Ph.D. Hitoshi Sekido M.D. Ph.D. Tomoyuki Morita M.D. Ph.D. Masako Kamiyama Ph.D. Daisuke Morioka M.D. Ph.D. Toru Kubota M.D. Ph.D. Yasuhiko Miura M.D. Ph.D. Kuniya Tanaka M.D. Ph.D. Takashi Ishikawa M.D. Ph.D. Yasushi Ichikawa M.D. Ph.D. Itaru Endo M.D. Ph.D. Hitoshi Goto M.D. Ph.D. Hiroyuki Nitanda M.D. Ph.D. Yasushi Okazaki M.D. Ph.D. Yoshihide Hayashizaki M.D. Ph.D. Hiroshi Shimada M.D. Ph.D. 《Journal of gastrointestinal surgery》2005,9(6):758-768
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver. 相似文献
16.
Yumiko Motoi Masashi Takanashi Masako Itaya Kazuhiko Ikeda Yoshikuni Mizuno Hideo Mori 《Neuropathology》2004,24(1):60-65
In the present case, a patient in whom limb apraxia and asymmetrical parkinsonism developed suggesting corticobasal degeneration, is reported. Neuropathologic examination revealed numerous tufted astrocytes in the precentral cortex in addition to the characteristic pathologic findings of PSP. Therefore, on the basis of clinicopathologic features, atypical progressive supranuclear palsy was diagnosed. In addition, the brain tissue of the present patient was investigated with an antibody specific for four‐repeat tau (4R‐tau). In the precentral cortex, numerous tau‐positive tufted astrocytes, pretangles, and threads were positive for 4R‐tau. Using a confocal microscopy we demonstrated that tufted astrocytes positive for 4R‐tau were adjacent to astrocytes positive for GFAP. The present findings suggest that accumulation of four‐repeat tau in astrocytes is a degenerative process rather than a reactive process. 相似文献
17.
18.
We compared the coronary vasodilator and cardiac effects of MCI-176, a novel quinazolinone calcium antagonist, in isolated, blood-perfused sinoatrial (SA) node, atrioventricular (AV) node, and papillary muscle preparations of dogs. The drug was administered intraarterially. In SA node preparations MCI-176 reduced sinus rate and produced atrial standstill in large doses. In AV node preparations MCI-176 prolonged AV conduction time and produced second- or third-degree AV block in large doses only when administered into the artery supplying the AV node, but failed to affect AV conduction when administered into the artery supplying the His-Purkinje-ventricular system. In paced papillary muscle preparations MCI-176 reduced the force of contraction. In spontaneously beating papillary muscles MCI-176 failed to change the beating rate. MCI-176 increased blood flow in all preparations. The dose that doubled blood flow was slightly larger than the dose that produced a 15% increase in AV conduction time, but about one-third the dose that produced a 15% decrease in sinus rate. The dose estimated to reduce the force of contraction by half was more than approximately 10 times the dose that doubled blood flow. The results indicate that MCI-176 can be classified as a nonvasoselective calcium antagonist but that it differs from others. 相似文献
19.
H. Kobayashi Y. Kotoura M. Hosono T. Tsuboyama C. Shigeno J. Konishi 《European radiology》1995,5(6):651-653
Melorheostosis is a benign sclerosing dysplasia with a very unusual and characteristic roentgenographic appearance. We reported a patient with melorheostosis in the left lower extremity followed up for 14 years. Although the extraosseous lesions only slightly enlarged, the bone scintigraphy showed the activity of the metabolism to be still high. 相似文献
20.
Terashima Y Onai N Murai M Enomoto M Poonpiriya V Hamada T Motomura K Suwa M Ezaki T Haga T Kanegasaki S Matsushima K 《Nature immunology》2005,6(8):827-835
Ligation of the chemokine receptor CCR2 on monocytes and macrophages with its ligand CCL2 results in activation of the cascade consisting of phosphatidylinositol-3-OH kinase (PI(3)K), the small G protein Rac and lamellipodium protrusion. We show here that a unique clathrin heavy-chain repeat homology protein, FROUNT, directly bound activated CCR2 and formed clusters at the cell front during chemotaxis. Overexpression of FROUNT amplified the chemokine-elicited PI(3)K-Rac-lamellipodium protrusion cascade and subsequent chemotaxis. Blocking FROUNT function by using a truncated mutant or antisense strategy substantially diminished signaling via CCR2. In a mouse peritonitis model, suppression of endogenous FROUNT markedly prevented macrophage infiltration. Thus, FROUNT links activated CCR2 to the PI(3)K-Rac-lamellipodium protrusion cascade and could be a therapeutic target in chronic inflammatory immune diseases associated with macrophage infiltration. 相似文献