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The migration of leukocytes into inflamed peripheral tissues and lymphoid organs involves a cascade of molecular events finely regulated by cell adhesion molecules and chemokines. Fractalkine/CX3CL1 is a membrane-bound chemokine that functions not only as a chemoattractant but also as an adhesion molecule, and is expressed on endothelial cells activated by proinflammatory cytokines. The fractalkine receptor, CX3CR1, is expressed on cytotoxic effector lymphocytes including NK cells and cytotoxic effector T cells (T(CE)), mature monocytes/macrophages, and mucosal dendritic cells, all of which play important roles in elimination of pathogens and cancer cells. Recently, accumulating evidence in both clinical studies and animal disease models has shown that fractalkine is also involved in the pathogenesis of various chronic inflammatory diseases, such as rheumatoid arthritis and atherosclerosis. This article reviews the unique functions of fractalkine and its pathophysiological roles in various clinical conditions.  相似文献   
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Design of a Centrifugal Blood Pump with Magnetic Suspension   总被引:1,自引:0,他引:1  
Abstract: A new concept blood pump, whose impeller is suspended by permanent magnets and a mechanical pivot without seals or ball bearings, is presented in this paper. The primary aim of the blood pump is an application to implantable artificial hearts. The prototype model is of a centrifugal type with a four-vaned semiopen impeller 50 mm in diameter. Since this mechanism has no seals or ball bearings, flow stagnation or heat generation that might cause blood cell denaturation is expected to be small. The results of performance testing for the prototype model 2 were satisfactory regarding pump head and efficiency. The radial-suspension magnets and the magnetic coupling were stable. As a result, the present mechanism has been verified to be a candidate applicable to implantable artificial hearts.  相似文献   
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We analyzed the cell surface phenotype of CD8+ cells in both peripheral blood and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). Utilizing the monoclonal antibodies anti-CD45RA, anti-CD29 and anti-S6F1-, one can define both suppressor effector (CD45RA+CD29-S6F1-) and killer effector (CD45RA-CD29+S6F1+) cells within the CD8 population. In patients with OA, normal proportions of CD8+CD45RA+, CD8+CD29+ and CD8+S6F1+ cells were found in both peripheral blood and SF. The peripheral blood of patients with RA, in contrast, showed a decreased percentage of CD8+CD45RA+ cells (13.4 +/- 2.6) (p less than 0.05), but a normal percentage of CD8+CD29+ and CD8+S6F1+ cells. In the SF of patients with RA, we observed a more dramatic decrease in CD8+CD45RA+ suppressor effector cells (6.4 +/- 5.0) (p less than 0.001), a significant increase in killer effector cells as measured by both CD8 + CD29+ (35.5 +/- 9.9) (p less than 0.001) and CD8 + S6F1+ cells (28.2 +/- 11.4) (p less than 0.01). These changes may contribute to the immunologic abnormalities previously noted in this disease and may provide some insight into the pathophysiologic mechanisms of RA.  相似文献   
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Clinical features of 16 patients with mild systemic lupus erythematosus (SLE) were compared with those of 21 control patients with moderate or severe disease. Age at the time of diagnosis of SLE was higher in mild disease group. The incidence of the coexistence of Sj?gren's syndrome (SS) at the time of diagnosis of SLE was higher in patients who later developed mild disease. Anti-Sm antibody and decreased levels of C3, C4, and CH50 occurred less frequently in patients with mild disease. SLE patients with the coexistence of SS at the time of diagnosis of SLE may represent a subset with a benign prognosis.  相似文献   
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T Takeda  T Shima  Y Okada  K Yamane  K Ohta  T Uozumi 《Brain and nerve》1989,41(11):1119-1125
A focal cerebral ischemic model was produced by occlusion of the intracranial main cerebral artery with a silicone cylinder in normotensive (NTR) and spontaneously hypertensive rats (SHR). Main cerebral artery could be successfully occluded in approximately 90%. The most frequent embolized site was the distal part of the internal cerebral artery (ICb) and less frequently the horizontal segment of the anterior cerebral artery (Al). Mortality rate of NTR with ICb occlusion (NTR-ICb) was 43% at 72 hours after embolization and that of SHR with ICb occlusion (SHR-ICb) was 67% at 24 hours after embolization. NTR-ICb showed neurological signs (i.e. circling movement, hemiparesis, poor response to pain stimuli) and histologically, showed infarction in the deep cerebral structures (i.e. thalamus, hypothalamus, hippocampus, and internal capsule) accompanied with mild disruption of blood-brain barrier (BBB). SHR-ICb showed more serious neurological signs and more severe cerebral infarction in the deep cerebral structures with severe disruption of BBB. In SHR-ICb, ischemic cerebral edema was more prominent which may deteriorate symptoms and pathological findings compared to NTR-ICb. This embolization model is proposed to be useful for studying the pathophysiology of focal cerebral ischemia, especially, early ischemic edema.  相似文献   
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A 64-year-old female was found to have localized ground-glass opacity (GGO) in the middle lobe on a chest computed tomography (CT) for screening. Middle lobectomy with video-assisted thoracoscopic surgery (VATS) was undertaken, and pathological diagnosis was a bronchioloalveolar carcinoma (BAC) in stage IA. A follow-up CT a year following the surgery revealed localized GGO in area S6 of the left lung. However, it disappeared during the gravitation-dependent gradient in the observation period. The patient was scanned again under prone position to exclude the gravitational effect, resulting in definite detection of the GGO. Left extended S6 segmentectomy with VATS was performed, and pathological diagnosis was a BAC in stage IA. As GGO existing in a gravitation-dependent area may be masked by the gravitation-dependent density, a change of the scanning position may lead to a proper detection of the tumor for the diagnosis of BAC.  相似文献   
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A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors.  相似文献   
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