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81.
OBJECTIVES: The role of estrogens in human bladder cancer still remains to be resolved. This study was undertaken to determine the estrogen receptor (ER) expression status and to elucidate the prognostic significance of ER in superficial transitional cell carcinoma (TCC) of the human bladder. METHODS: Tumor tissue blocks which were obtained by transurethral resection (TUR) from 121 patients with superficial TCC and 30 control subjects were investigated. Median follow-up was 40 months. The expression of nuclear ER was evaluated by immunohistochemistry using avidin-biotin-peroxidase method and a monoclonal ER antibody. ER staining intensity in samples was assessed semi-quantitatively. Staining characteristics were compared with the clinico-pathological results. RESULTS: ERs were detected in 12.4% of the superficial TCC patients and in 10% of the controls (P = 0.73). No association was found between ER immuno-reactive score and patients' age, sex, tumor multiplicity or tumor size. An association between the ER staining intensity and higher tumor grade was observed (P = 0.01). Grades I, II and III tumors showed 10.6, 8.7 and 44.4% staining, respectively. Survival was not affected by ER expression. In multivariate analysis ER expression was not an independent prognostic factor. CONCLUSION: Superficial TCC of the bladder shows low ER expression and it appears that ERs do not have any direct role on the prognosis of patients with superficial TCC.  相似文献   
82.
OBJECTIVE: Nephrotoxicity is the major adverse effect of amphotericin B (AmB), often limiting administration of full dosage. Selective distal tubular epithelial toxicity seems to be responsible for the profound potassium wasting that is a major clinical side effect of treatment with AmB. Potassium depletion also potentiates the tubular toxicity of AmB. This study was designed to assess the ability of spironolactone to reduce potassium requirements and to prevent hypokalemia in neutropenic patients on AmB treatment. METHODS: In this study 26 patients with various hematological disorders were randomized to receive either intravenous AmB alone or AmB and oral spironolactone 100 mg twice daily when developing a proven or suspected fungal infection. RESULTS: Patients receiving concomitant AmB and spironolactone had significantly higher plasma potassium levels than those receiving AmB alone (P = 0.0027). Those patients receiving AmB and spironolactone required significantly less potassium supplementation to maintain their plasma potassium within the normal range (P = 0.022). Moreover, urinary potassium losses were significantly less in patients receiving AmB and spironolactone than those receiving AmB alone (P = 0.040). CONCLUSION: This study showed that spironolactone can reduce potassium requirements and prevent hypokalemia by reducing urinary potassium loss in neutropenic patients on AmB treatment.  相似文献   
83.
T-large granular lymphocyte lymphoproliferative disorder (T-LGL LPD) is an indolent disease characterized by prolonged cytopenia and the presence of circulating large granular lymphocytes in the patient's peripheral blood. Although the disease is commonly thought of as indolent, most patients eventually require therapy because of recurrent infections secondary to neutropenia as well as a need for frequent blood product transfusions. CD26 is a 110-kDa surface glycoprotein with an essential role in T-cell function, including being a marker of T-cell activation and a mediator of T-cell activating signals. In this study, we evaluated CD26 expression in T-LGL patients and correlate CD26 expression with clinical behaviour. In addition, we examined the potential mechanism of cytopenia that is associated with this disorder. Our findings suggest that CD26 is a marker of aggressive T-LGL LPD and that CD26-related signalling may be aberrant in T-LGL LPD. Furthermore, inhibition of granulocyte-macrophage colony-forming units may be mediated by CD8+ cells of T-LGL LPD patients and is major histocompatibility complex class I-restricted.  相似文献   
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85.
HYPOTHESIS: Various forms of electrical stimulation can improve wound healing in different tissues, but their application to gastrointestinal tract healing has not been investigated. We assumed that positively charged diethylaminoethyl cross-linked dextran bead (diethylaminoethyl Sephadex [DEAE-S]) particles would have a beneficial effect on the healing of colonic anastomoses. DESIGN: Experimental animal study. SETTING: Animal research laboratory of a university hospital. ANIMALS: Forty female Wistar albino rats. INTERVENTIONS: Right colonic transection and anastomosis was performed in 5 animal groups. The control group received no treatment; the placebo group, methylcellulose gel; and the DEAE-S group, DEAE-S in methyl cellulose gel applied topically around the anastomoses. The fecal peritonitis (FP) group underwent cecal ligation and perforation simultaneously with the anastomosis to cause FP; the FP + DEAE-S group also received DEAE-S applied around the anastomoses. MAIN OUTCOME MEASURES: After the completion of postoperative day 4, all rats were killed. Anastomotic bursting pressures and hydroxyproline concentrations in perianastomotic tissue were measured and compared. RESULTS: Mean bursting pressures were 115.1 mm Hg in the control group, 113.6 mm Hg in the placebo group, 159.4 mm Hg in the DEAE-S group, 62.8 mm Hg in the FP group, and 121.1 mm Hg in the FP + DEAE-S group (P =.001, 1-way analysis of variance [ANOVA]). The differences between the control vs DEAE-S groups, placebo vs DEAE-S groups, and FP vs FP + DEAE-S groups were significant (P<.05, t test). Mean hydroxyproline concentrations were 5.2 microg/mg in the control group, 4.9 microg/mg in the placebo group, 5.6 microg/mg in the DEAE-S group, 4.5 microg/mg in the FP group, and 5.4 microg/mg in the FP + DEAE-S group (P =.09, 1-way ANOVA). The difference between the FP and FP + DEAE-S groups was significant (P =.04, t test). CONCLUSIONS: A positively charged particle, DEAE-S, improves healing of colonic anastomoses in healthy rats and in rats with FP. This inexpensive, nontoxic material is easily applied and deserves further evaluation in gastrointestinal tract healing.  相似文献   
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87.
BACKGROUND: Intraluminal brachytherapy has become an established treatment for major airway occlusion by relapsed or persistent inoperable endobronchial tumors. The aim of this study was to compare the palliation improvement pre- and post-radiotherapy. METHODS: The study group was 95 patients with the diagnosis of inoperable lung cancer who were eligible for HDR brachytherapy. Fiber-optic bronchoscopy was performed and the level and degree of endobronchial obstruction were estimated in terms of bronchial obstruction index. Endobronchial irradiation was delivered using remote HDR afterloading brachytherapy with iridium-192. Brachytherapy was delivered at weeks 1, 2 and 3 at 7.5 Gy per fraction or at weeks 1 and 2 at 10 Gy per fraction. All patients were evaluated at the beginning and at the third month of therapy. Using Speiser's symptomatic scoring criteria, the severity of symptoms (dyspnea, cough, hemoptysis and postobstructive pneumonia) was weighted. Bronchoscopic findings at the initial evaluation and at the third month were also scored. Surviving patients were followed up for a minimum of 3 months with a mean of 7.5 +/- 5.35 months (median: 6 months). RESULTS: All the symptoms and bronchial obstruction improved significantly after brachytherapy (P < 0.05). The most responding symptoms were dyspnea and hemoptysis. The factors determining the complete response were evaluated; age, staging, histological type, lesion localization and previous history of radiotherapy did not seem to determine the complete response (P > 0.05). CONCLUSIONS: All the symptoms and bronchial obstruction index seemed to improve after brachytherapy. However, it is difficult to predict the response before the therapy.  相似文献   
88.
BACKGROUND AND OBJECTIVES: The aim of this study was to investigate whether systematic lymphadenectomy is necessary in suboptimally cytoreduced patients with stage III ovarian carcinoma. METHODS: Prognostic significance and the effect on survival of systematic pelvic and para-aortic lymphadenectomy were investigated retrospectively in 61 suboptimally debulked patients with stage III ovarian carcinoma. All patients received platinum-based chemotherapy after surgery; 51 patients had been followed for > or =1 year, or until death. Survival curves were calculated according to the Kaplan-Meier method and were evaluated by log-rank test. RESULTS: Most patients had stage IIIC disease (60.7%), poorly differentiated tumor (45.9%), and serous histological type (59%). Systematic pelvic and para-aortic lymphadenectomy was performed in 29 patients (47.5%). Lymph node metastases were found in 17 (58.6%) patients; the median number of metastatic nodes was 7 (5-10). Lymph node metastasis was significantly higher in patients with residual disease of >2 cm (P < 0.05). Both univariate and multivariate analyses showed that systematic pelvic and para-aortic lymphadenectomy was not a significant prognostic factor (P > 0.05). In lymph node-dissected patients, survival was significantly longer in patients with minimal residual tumor than in those with residual tumor size >2 cm (P = 0.005). CONCLUSIONS: Lymphadenectomy seems not to have an evident prognostic value and a benefit on survival in suboptimally debulked patients with stage III ovarian carcinoma.  相似文献   
89.
BACKGROUND: Antithrombin III is known as the most important natural inhibitor of thrombin activity and has been shown to attenuate local harmful effects of ischemia-reperfusion injury in many organs. In recent animal studies, delaying effect of remote organ ischemia-reperfusion injury on healing of intestinal anastomoses has been demonstrated. In this study, we investigated whether antithrombin III reduces deleterious systemic effects of ischemia-reperfusion injury on healing of colonic anastomoses in rats. METHODS: Anastomosis of the left colon was performed in 24 rats that were divided into three groups: sham operated control (group I, n = 8), 30 minutes of intestinal ischemia-reperfusion by superior mesenteric artery occlusion (group II, n = 8), antithrombin III treated group (250 U/kg before and after the ischemia-reperfusion, group III, n = 8). On postoperative day 6, all animals were sacrificed, and bursting pressure and tissue hydroxyproline content of the anastomoses were assessed and compared. RESULTS: On postoperative day 6 the mean bursting pressures were 149.6 +/- 4.8, 69.8 +/- 13.5, and 121.8 +/- 8.7 mm Hg for groups I, II, and III, respectively (P = 0.000). Mean tissue hydroxyproline concentration values were 389.5 +/- 29.6, 263.1 +/- 10.0, and 376.0 +/- 33.8 microg/mg for groups I, II, III respectively (P = 0.005). CONCLUSIONS: This study showed that, antithrombin III treatment significantly prevented the delaying effect of remote organ ischemia-reperfusion injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether antithrombin may be a useful therapeutic agent to increase the safety of the anastomosis during particular operations where remote organ ischemia-reperfusion injury takes place.  相似文献   
90.
There is no study based on objective measurements about the cosmetic results of myringoplasty operation in medical literature. This study aims to show the differences in the auriculomastoid angle between the operations which were done with postauricular and endaural incisions. The auriculomastoid angle of 20 patients having had postauricular myringoplasty operation were measured both preoperative and postoperative periods. The auriculomastoid angles of 17 patients having had endaural myringoplasty operation were also measured in both preoperative and postoperative periods. Also, the patients were asked whether there was a change in the shape of their ears. It was observed that the increase of the auriculomastoid angles of the patients who had myringoplasty by postauricular incision was statistically significant when compared to the ones having had the operation by endaural incision. Also, the patients who had myringoplasty operation by postauricular incision realized the change in their ears significantly when compared to the other group. In this study, esthetically better results were observed in the myringoplasty operations done by endaural incision than the ones done by postauricular incision. When deciding on the incision type, this should be considered.  相似文献   
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