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31.
We reported a new monoclonal antibody, designated FUB-1, reacting with normal and neoplastic large lymphoid cells. FUB-1 was produced using a Burkitt's lymphoma cell line (HBL-5) as an immunogen. Its immunoglobulin subtype was IgM. The determinant was not on the surface but in the cytoplasm. Western blotting analysis revealed that the molecular weight of the antigen was 52,000 dalton. In the normal lymphoid tissue, FUB-1 reacted with large lymphoid cells, but not with small or medium-sized lymphoid cells or plasma cells. In addition, the FUB-1 antigen was not found in resting cells in the peripheral blood (PB), but it was induced on mononuclear cells of PB by addition of PWM or PMA. In the B-cell lymphomas tested, FUB-1 reacted with small cleaved cell lymphomas (3/12), large cell lymphomas (7/10), Burkitt's lymphomas (4/4) and immunoblastic lymphomas (2/2), but not with small cell lymphomas (0/3) or intermediate lymphocytic lymphomas (0/8). These findings indicate that the FUB-1 antigen appears to be expressed on normal lymphoid cells during blastoid transformation and on neoplastic large lymphoid cells. FUB-1 also reacted with normal glandular epithelium and various adenocarcinomas. FUB-1 may be useful to investigate the mechanism of in vitro blastoid transformation or activation of lymphoid cells.  相似文献   
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Four human monoclonal rheumatoid factors (MRF) were used to raise a panel of mouse monoclonal antibodies (mAb) which were selected in a solid-phase radioimmunoassay for binding to MRF but not normal IgM. Three mAb, each raised against a different MRF, bound to the majority of MRF and also to most polyclonal RF. Four other mAb bound selectively to the MRF against which they were raised and to no other MRF, and rarely to any polyclonal RF. Competition studies using cold and radiolabeled mAb further indicated that these mAb recognize distinct and different epitopes on MRF. RF activity of MRF was inhibited by 3 of the 4 mAb binding to a single MRF and 2 of the 3 mAb binding to multiple RF. It was thus concluded that of this panel of mAb 3 recognized cross-reactive idiotopes and the remainder demonstrated highly restricted idiotopes on MRF. These mAb identified MRF idiotopebearing cells in the peripheral blood of 3 of the MRF donors (and a further subject with type II essential cryoglobulinemia), with a frequency ranging from 0.3–10% of all mononuclear cells with the mAb to restricted idiotopes or 1.5–17% with mAb to cross-reactive idiotopes. These anti-idiotopic mAb should thus provide a highly specific means of identifying and monitoring MRF-producing cells in vivo.  相似文献   
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Minimal osteonecrosis as a segmental infarct within the femoral head   总被引:3,自引:0,他引:3  
Minimal osteonecrosis (MON) is a small and eccentrically localized lesion of osteonecrosis (ON) of the femoral head. This form of ON shows clinically benign features, but may be indicative of the pathomechanism of ON. Of 180 patients (275 hips) with ON, 15 patients (19 hips) were found to have MON. Based on the geography of the femoral head, the lesions were grouped into four types: anterior (seven hips), superior (six hips), medial (five hips), and lateral (one hip). When the location of the lesion was compared with the normal vascular anatomy, a close correlation between the location and the segmental blood supply in the femoral head became evident. Histologic findings showed localized infarction of the trabeculae and bone marrow, but no evidence suggesting repeated episodes of infarction, which is an essential feature of typical ON. From these findings, MON may be a segmental infarct within the femoral head. Interruption of the blood flow may possibly occur not in the main trunk but in the terminal branch of the lateral epiphyseal or superior metaphyseal artery; such as ischemic event is probably a single brief attack, leading to this form of infarction in contrast to typical ON developing with prolonged or recurrent obstructions.  相似文献   
36.
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients.  相似文献   
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A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
39.
A boy with skin eruptions resembling varicella and specific for Langerhans cell histiocytosis (LCH) is reported. At his initial visit when he was four months old, vesiculopustular lesions were present over the entire body; these had first appeared on the third day post partus. Histopathological, immunohistochemical, and electron microscopical examination confirmed the Langerhans cell phenotype and Birbeck granules in the responsible cells. He also had hydronephrosis, recurrent fever, and cutaneous bacterial infections. His parents refused further medical treatment and he died of diarrhea with cachexia about two years later. LCH may present diagnostic difficulties by manifesting as a skin eruption which resembles varicella.  相似文献   
40.
Prostatic cancer is one of the most common malignant tumors in the field of urology. The number of patients is increasing rapidly and its importance as a mortal disease is gathering attention. In 1985, we organized a registration system for prostatic cancer patients found in and around Gunma prefecture. In this study, we analyzed the clinical characteristics of the 730 patients registered from 1985 to 1989. The results were as follows. Mean age was 74.0 years old and the number of the patients was the greatest in the eighth decade. Voiding disturbance was the most common chief complaint, followed by pollakisuria, gross hematuria and miction pain. Stage and grade distribution were as follows. Stage A 16.2%, B 21.1%, C 17.0%, D 45.7%, well differentiated 27.4%, moderately differentiated 48.2% and poorly differentiated 24.5%, respectively. A statistically significant relationship between stage and grade was observed. Bone was the most common metastatic site. The highest incidence of bone metastasis was in lumbar vertebra, followed by ribs, ilium, thoracic vertebra and ischium. The value of PAP, ALP and ESR tended to be higher in high stage patients, and that of Hb was lower. Fifty two patients were detected by mass screening. Most of these patients were in an early stage. Most of the patients were treated by hormonal therapy. LH-RH agonists constituted 39.2% of the cases given hormonal therapy.  相似文献   
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