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41.
AIM OF THE STUDY: Although a bleeding tendency as a first symptom is a critical condition in congenital biliary dilatation (CBD), the clinical details of this symptom remain unclear. We assessed this condition in children with CBD in this paper. MATERIALS AND METHODS: Sixty-five children with CBD were treated at our institute between 1983 and 2004. The children, initially presenting with bleeding manifestations such as intracranial hemorrhage and bloody stools, were defined as the bleeding group, and the remaining children with digestive symptoms such as abdominal pain and vomiting were defined as the digestive group. The clinical features were compared between these two groups. RESULTS: In 6 of the 65 cases, bleeding manifestations were noted (9.2 %). All six had cystic-type choledochal dilatation. The mean age of the bleeding group was significantly younger than that of the digestive group, and bleeding was more frequent, especially in infants less than 12 months of age. In a laboratory study, the bleeding group showed a more prolonged blood coagulation time than the digestive group did. Serum amylase and lipase levels in the bleeding group were almost normal, while those in the digestive group were significantly higher. The direct bilirubin level in the bleeding group was significantly higher than that in the digestive group. CONCLUSIONS: Disturbed blood coagulation due to vitamin K deficiency related to cholestasis results in a bleeding tendency in children with CBD. Therefore, pediatric surgeons should be aware of this rare but critical condition which can be prevented by rapid and precise treatment with vitamin K supplementation.  相似文献   
42.
M Abe  N Ono  K Tominaga  H Hojo  M Seto  S Fukuhara  H Wakasa 《Cancer》1992,70(4):821-829
Immunohistochemical and molecular genetic (bcl-2 gene) studies were performed on specimens from 24 patients with follicular small cleaved cell lymphoma (FSCCL), 24 patients with diffuse small cleaved cell lymphoma (DSCCL) and 4 patients with mantle zone lymphoma (MZL) to determine the cellular origin of the disease and whether or not DSCCL represents the diffuse counterpart of FSCCL. Two patients with FSCCL, 22 patients with DSCCL, and all of the patients with MZL had a phenotype of mantle zone (MZ) B-lymphocytes (SIgD+, Leu-1+, Leu-8+, positive alkaline phosphatase [ALPase+], and negative common acute lymphoblastic leukemia antigen [CALLA-]), and all the tested patients (2 patients with FSCCL, 13 patients with DSCCL, and 4 patients with MZL) had germlines of bcl-2 gene. Fourteen patients with FSCCL and 1 patient with DSCCL had a phenotype of follicular center cells (FCC) (CALLA+, SIgD-, Leu-1-, Leu-8- and negative ALPase), and 11 patients with FSCCL had bcl-2 gene rearrangements. These results indicate that FSCCL are almost always derived from FCC, whereas some FSCCL, most DSCCL, and all MZL are derived from MZ B-lymphocytes, and these lymphomas should be included in the same category as MZ B-lymphocyte-derived lymphomas. Histologically diagnosed DSCCL often may represent a diffuse counterpart of MZ B-lymphocyte-derived lymphoma. MZ B-lymphocyte-derived lymphomas histologically show a follicular (nodular), a follicular MZ, or a diffuse growth pattern and clinically show a high incidence of peripheral blood (PB) involvement or bone marrow (BM) involvement.  相似文献   
43.
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   
44.
45.
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   
46.
47.
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   
48.
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   
49.
50.
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   
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