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101.
Neutrophils from the synovial fluid (SFN) of 10 patients with active rheumatoid arthritis (RA) were investigated to determine the generation of oxygen intermediates (OI) (O2-, H2O2, OH .), chemiluminescence, and lysosomal enzymes (lysozyme and beta-glucuronidase). Lymphocytes from healthy individuals were cocultured at 37 degrees C for 17 hr with SFN from the patients and the number of OKT4+, OKT8+, and OKT3+ cells and the response to mitogens were determined. A markedly increased OI and slightly elevated lysosomal enzyme levels were observed in SFN from patients. Coculture of lymphocytes with SFN resulted in a decreased number of OKT4+ and OKT8+ cells and a greatly reduced response to Con A and mildly diminished response to PHA, while OKT3+ cells were not affected. The simultaneous addition of superoxide dismutase and catalase restored the impairment of monoclonal antibody reaction and lymphocyte responsiveness almost to control levels. It is suggested that the disturbed immunoreactivity of synovial fluid lymphocytes from RA patients may be due to increased OI generated by stimulated neutrophils.  相似文献   
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Tetrasomy 8, though rare, is usually associated with trisomy 8, a far more common chromosomal abnormality in acute myeloid leukemia (AML). Yet the clonal relationship between trisomy 8 and tetrasomy 8 in the cases with these chromosomal abnormalities has been unclear. Here, we report a case of a 17-year-old male, diagnosed as having a myelodysplastic syndrome (MDS). Chromosome analysis showed the presence of trisomy 8. Five years later, he developed overt AML exhibiting tetrasomy 8 only. After chemotherapy, the blast cells in the bone marrow decreased to 3.4%, and the karyotype showed trisomy 8 alone. Fluorescence in situ hybridization using a probe specific for chromosome 8 showed that the percentages of cells exhibiting 2/ 3 /4 signals were 7.8/89.2/2.0 at the MDS stage, 20.5/36.1/41.0 when overt AML developed and 24.0/72.1/2.4 after chemotherapy. These results suggested that tetrasomy 8 is derived from the AML clone, possibly evolved from the MDS clone with trisomy 8. To our knowledge, this is the first detailed case report of clonal evolution from trisomy 8 into tetrasomy 8 associated with the development of AML from MDS.  相似文献   
104.
225 patients who received partial gastrectomies more than five years ago were examined by endoscopy with mucosal biopsies. In the biopsies taken from mucosa close to the anastomosis, hyperplasia of the foveolar epithelium and glandular cysts, findings identical with "gastritis cystica polyposa", were most often seen following Billroth II resection. Cases in which more than 20 years had elapsed since Billroth II resection revealed the highest rate (65.2%) of such mucosal changes. A close relationship between 2 cases (B-II Group) of gastric stump carcinoma detected near the gastro-enteric anastomosis and such mucosal changes is suggested.  相似文献   
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We carried out a histologic, immunohistochemical and ultrastructural study of 19 tumors, previously classified as Ewing's sarcoma of the bone (ESB). The tumors were categorized histologically into four groups according to the presence or absence and the distribution of Homer-Wright rosettes, together with the immunohistochemical and ultrastructural features: 1) neuroectodermal tumor of bone (NTB) with diffusely dispersed rosettes (4 cases), 2) conventional ESB totally lacking the rosettes (9 cases), 3) intermediate-type tumor with characteristics of both NTB and ESB (4 cases), and 4) spindle cell-type tumor with focal rosettes (2 cases). Ultrastructurally, NTB contained neurotubules and neurosecretory granules, whereas ESB consisted of only undifferentiated cells. Immunoreactivity with antineural antibodies, such as Leu-7, and those against synaptophysin, NSE, neurofilament, and chromogranin, was detected in the majority of NTB, in intermediate- and spindle cell-type tumors and in two of the nine cases of ESB. In view of these findings, we propose that use of the term "neuroectodermal tumor of the bone" should be restricted to tumors with an extensive distribution of rosettes, and that those without unequivocal rosettes should be classified as ESB, although ESB may be the most undifferentiated form of NTB and some overlap may occur between the two tumor types.  相似文献   
107.
One-hundred-and-twenty patients underwent first cadaveric kidney transplantation from the non-heart beating donors. All of the organs were procured with the use of double balloon catheter for in situ cooling. The mean warm ischemic time and cold ischemic time were 10.7 +/- 17.0 minutes and 18.9 +/- 11.4 hours, respectively. One- and 5-year graft survival rates were 85.0 and 72.7%, respectively. Among 120 recipients, 30 (25%) grafts functioned immediately (immediate function), 82 (68.3%) grafts functioned after varying length of oliguric periods (delayed function) and 8 (6.7%) grafts never functioned (non-function). The mean age of the donors in the group of immediate function (31.5 +/- 16.1 yr) was significantly lower than those of other two groups. The mean warm ischemic time in the group of immediate function (6.0 +/- 11.2 min) was significantly shorter than that of delayed function. However, there was no significant difference in donor hypotensive episode, types of preservation fluid and cold ischemic time between the groups. The conclusion is that the ultimate result of cadaveric kidney transplant from the non-heart beating donors with the use of double lumen catheter is acceptable despite a relatively high incidence of delayed graft function.  相似文献   
108.
Thirty-six previously untreated cases of head and neck cancer were given a combined therapy of irradiation and intra-arterial, one-shot injection of Cisplatin. As a result, the primary lesions in 35 cases were seen to achieve a 66% complete remission (CR) and a 100% overall response (OR). The lymph metastases in twenty-one cases with positive node achieved a 62% CR and a 100% OR. Good, local control of supraglottic and hypopharyngeal cancers were found to be an advantageous factor considered from the standpoint of the "quality of life". The cumulative survival rate, using Kaplan-Meier's method, was 82% for the first year, and 62% for the second year. No severe side effects were observed.  相似文献   
109.
Objectives Describe contribution of laryngeal movement to pressure changes at the upper esophageal sphincter (UES) and the effect of aging on the swallowing function. Study Design Manofluorography on 56 nondysphagic adults divided into three age groups: the 21‐ to 31‐year‐old group (n = 32), the 61‐ to 74‐year‐old group (n = 12) and the 75‐ to 89‐year‐old group (n = 12). Analyses of the bolus transit time, the amplitudes and durations of pharyngeal pressures, the timing of a pressure fall at the UES and the laryngeal movements. Methods Intraluminal strain‐gauge sensors recorded pressure changes in the oropharynx, hypopharynx and the UES. Motion pictures of the videotapes were fed into a personal computer, and movements of the hyoid bone were measured in both the horizontal and vertical directions as an indication of laryngeal movement. Results In 26‐ and 70‐year‐old men with calcification of the thyroid cartilage, it was determined that the larynx and hyoid bone moved in consonance until the end of the rapid hyoid movements in both the superior and anterior directions. In the 21‐ to 31‐year‐old group, the magnitude of the pressure fall at the UES was maximal before or almost at the same time as the bolus arrival, in preparation for smooth passage of the bolus from the pharynx to the esophagus. The rapid superior movements of the hyoid bone started significantly early as compared with its anterior movements (P = .0001). The rapid anterior movements of the hyoid bone started simultaneously with the pressure fall at the UES. In the elderly, all segmental transit times were significantly increased. The timing of the pressure fall at the UES was significantly delayed and the UES pressure reached its minimum value after arrival of the bolus at the UES. The minimum pressure at the UES increased to a significantly positive value. The rapid anterior movements of the hyoid were significantly delayed, suggesting that this delay causes the delay in the pressure fall at the UES. Conclusions The rapid superior and anterior movements of the hyoid bone are considered to start at the same time as those of the larynx. In the young group, it is suggested that superior laryngeal movement protects the lower airway prior to the anterior laryngeal movement, causing the pressure fall at the UES to enable the passage of a bolus into the UES. In the elderly, smooth passage of the bolus from the pharynx to the esophagus is hindered and the system that prevents aspiration is rendered inefficient by changes in the swallowing pressures and laryngeal movements with aging.  相似文献   
110.
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