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We used an immunohistochemical technique with the monoclonal antibody Ki-67, which recognizes nuclear antigen expressed in proliferating cells to determine the growth fractions of 5 normal mucosa specimens and 55 transitional cell carcinomas of the bladder. Normal mucosa had a mean value of 0.37 +/- 0.35% cells positive for Ki-67, whereas 9 histological grade 1 tumors showed 2.2 +/- 1.5%, 31 grade 2 tumors averaged 10.1 +/- 7.5% and 15 grade 3 tumors yielded 19.5 +/- 9.0%. These values were significantly different from each other (p less than 0.01), with Ki-67 indexes for grade 2 varying from 0.3 to 24.6%. Nonpapillary tumors had significantly higher indexes than papillary tumors (20.1 +/- 8.0 versus 6.7 +/- 5.9, p less than 0.01). The Ki-67 indexes were 4.6 +/- 4.5% for stage Ta (20 cases), 7.8 +/- 4.7% for stage T1 (14) and 20.2 +/- 7.8% for stages equal to or higher than T2 (21). Significant differences were noted between stages Ta and T1 (p less than 0.05) and between stages T1 and T2 or greater (p less than 0.01). Tumors with muscle layer invasion often showed more than 15% Ki-67 positive cells. Our results imply that Ki-67 indexes not only provide objective information to determine a malignant potential but also help to select the treatment.  相似文献   
13.
Respiratory complications associated with tracheal intubation and extubation   总被引:11,自引:1,他引:10  
We conducted a prospective survey on the incidence of respiratory complications associated with tracheal intubation and extubation in 1005 patients who underwent elective general anaesthesia over a 4-month period. During induction of anaesthesia, respiratory complications occurred in 46 patients (4.6%; 95% confidence limits (CL): 3.3, 5.9%). The common complications were coughing (1.5%) and difficult ventilation through a facemask (1.4%). Tracheal intubation was difficult in eight patients (0.8%). Complications occurred immediately after tracheal extubation in 127 patients (12.6%; 95% CL: 10.6, 14.7) and in the recovery room in 95 patients (9.5%; 95% CL: 7.6, 11.3%). The common complications immediately after extubation were coughing (6.6%) and oxygen desaturation (SaO2 < 90%) (2.4%), and in the recovery room, airway obstruction (3.8%) and coughing (3.1%). The incidence of complications was significantly higher immediately after tracheal extubation than during induction of anaesthesia (P << 0.001). Even when all incidents of coughing that occurred after tracheal extubation were disregarded as a complication, the overall incidence was still higher immediately after extubation (7.4%) than during induction of anaesthesia (P < 0.01). We conclude that the incidence of respiratory complications associated with tracheal extubation may be higher than that during tracheal intubation.   相似文献   
14.
Two cases underwent a modified Fontan operation with simultaneous superior vena cava-right pulmonary artery end-to-side anastomosis, which we called "bidirectional Glenn shunt". This anastomosis seems to be so effective for reduction of right arterial volume loading, and could proved life-saving in the case with the acute obstruction at the site of the right atriopulmonary artery anastomosis immediately after surgery.  相似文献   
15.
BACKGROUND: The aim of this study was to analyze cellular and cytokine interactions governing the development of synovial tissue outgrowth in patients with rheumatoid arthritis (RA). METHODS: A single-cell suspension of dissociated synovial tissues of RA patients was cultured for a long period to develop tissue outgrowth. The resulting tissue outgrowth was characterized by immunohistochemical staining and ELISA. RESULTS: The tissue outgrowth developed in vitro included various cell types, such as macrophage-like synovial cells, fibroblast-like synovial cells and lymphocytes. Even after prolonged cultivation, synovial cells devoid of infiltrating T lymphocytes did not form tissue outgrowth. The outgrowth contained CD3+ cells, LeuM3 (CD14)+ cells and HLA-DR+ cells. The T cells expressed lymphocyte function-associated antigen (LFA)-1 and CD2, and the synovial cells expressed intracellular adhesion molecule (ICAM)-1 and LFA-3, suggesting possible interactions via LFA-1/ICAM-1 and CD2/LFA-3. Production of T-cell derived IFN-gamma and IL-17 and synovial-cell-derived fibroblast growth factor (FGF)-1 and IL-15 was confirmed in the tissue outgrowth as well as in RA synovial tissue. These cell types stimulate each other by secreting cytokines, leading to the secretion of proinflammatory cytokines and matrix metalloproteinase (MMP)-1 by the tissue outgrowth and proliferation of both lymphocytes and synovial cells. CONCLUSION: This study emphasizes the importance of cellular interactions between T cells and synovial cells, via adhesion molecules and the secretion of cytokines with stimulatory activity towards other cell types, for the hyperactivity of RA synovial cells.  相似文献   
16.
Urinary bilharziasis is a parasitic infection responsible for vesical, urethral and renal lesions. The authors demonstrate the importance of ambulatory echography on a large scale and describe various echographic lesions. Vesical attacks occurred in 27% of the wall irregularity, 44% of the masses and polyps. Pyelic and urethral abnormalities occurred in 16.6% and 29.9% of cases respectively at the baseline in 1991. These prevalence rates decreased after seven years, in 1998. The authors discuss the utility of chemotherapy with praziquantel and the necessity of a periodical mass treatment in the areas with high bilharziasis endemicity in Mali.  相似文献   
17.
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990.  相似文献   
18.
Early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH)/ataxia with oculomotor apraxia type 1 (AOA1) is caused by mutations in the gene encoding aprataxin (APTX). Although several in vitro findings proposed that impaired enzymatic activities of APTX are responsible for EAOH/AOA1, potential instability of mutant proteins has also been suggested as the pathogenesis based on in vivo finding that mutant proteins are almost undetectable in EAOH/AOA1 tissues or cells. The present study aimed to experimentally prove instability of mutant proteins in neuronal cells, the cell type preferentially affected by this disease. Results of pulse-chase experiments demonstrated that all of the disease-associated mutants had extremely shorter half-lives than the WT. We further found that mutants were targeted for rapid proteasome-mediated degradation. These results help establish pathogenic and physiological protein characteristics of APTX in neuronal cells.  相似文献   
19.
Thymic epithelial reticular cells (TER) are heterogeneous cell populations. Of 14 rat monoclonal antibodies (moAbs) raised against established cell lines of mouse thymic stromal cells (TSC), two were found to recognize TER subpopulations that exhibited distinct intrathymic distributions. MoAb B6TS-1 (IgG2a) recognized the cell-surface determinant mB6TS-1 on TSC in the subcapsular zone, cortico-medullary junction, and medulla. Double staining with antikeratin antiserum showed that, except in the cortex, the distribution of mB6TS-1 bearing cells highly corresponded with that of keratin-positive TER indicating that mB6TS-1 within the thymus was selectively expressed in a particular subpopulation of epithelial cells. Immunoelectronmicroscopy revealed clear polarity in the expression of mB6TS-1 on TER. In the subcapsular zone. TER adherent to fibrous capsule expressed mB6TS-1 on the cell surface that faced the lymphocytes. In the cortico-medullary junction, mB6TS-1 also was found on the side of the TER closely associated with the small blood vessels. The mB6TS-1-bearing cells in the medulla characteristically had cytoplasmic infoldings containing collagen fibrils and amorphous material but did not exhibit the polarity of mB6TS-1-bearing cells. The mB6TS-1-bearing TER were interconnected by desmosomes and tonofilaments, therefore, were easily distinguished from macrophages, dendritic cells, and other components of thymic stroma. In contrast, another moAb AKTS-1 (IgM) stained the keratin-positive TER localized in the subcapsular zone and cortex forming a fine meshwork but did not stain those in the medulla. MoAb B6TS-1 stained thymic nurse cells but not the central cells of thymic rosettes, whereas moAB AKTS-1 did neither. Formation of lymphoid-stromal cell complexes in vitro was not affected by either antibody.  相似文献   
20.
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