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OBJECTIVE: Autophagy is a form of physiological programmed cell death which is observable after hormonal withdrawal. In this study, the FM3A murine breast tumor cell line was treated with epirubicin alone and with medroxyprogesterone acetate (MPA) or tamoxifen, to determine if structural and kinetic signs of autophagy may also occur in an enhanced manner during epirubicin sensitization via hormonal agents. METHODS: One-week soft agar colony growth, 96-hour values of plating and pulse thymidine labeling and electron microscopical examinations were performed following treatment with MPA and tamoxifen alone or with epirubicin. RESULTS: Tamoxifen induced signs of autophagy, which was enhanced when it was combined with MPA. Epirubicin also induced autophagy of secretory granules, which coalesced to form an intracytoplasmic lumen. Combining MPA with epirubicin enhanced the formation of apoptotic blebs and chromatin fragmentation. When epirubicin was combined with tamoxifen, peculiar nuclear structures were formed. CONCLUSIONS: Hormonal agents may modulate anthracycline activity towards specific patterns in eliciting cell death, via autophagy and/or as yet unknown nucleolus-specific interactions.  相似文献   
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In the blood samples obtained from a total of 68 patients with cancers of the urinary bladder, prostate, and cervix, who applied to the Departments of Urology, Obstetrics, and Gynecology of Hacettepe Medical Faculty, neutralizing antibodies were sought for against herpes simplex type 2 by neutralization test. The same test was applied to 35 control patients with no known malignancies. In contrast to the presence of the antibody in 62.86% of the control subjects, this ratio was 90.70% in patients with cancer of the urinary bladder, 87.50% in those with prostatic carcinoma, and 88.89% in those with cancer of the cervix.  相似文献   
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Abstract Background : The aim of the present study was to determine the prevalence, associated symptoms, and clinical outcomes of children with acute abdominal pain who had been admitted to an emergency department. Methods : Children aged between 2 and 16 years who presented to the emergency department of Cerrahpa?a Medical School, Istanbul University between July 2001 and August 2002 with acute abdominal pain were enrolled in this study. A questionnaire was completed each patient admitted to our pediatric emergency unit for acute abdominal pain. Data collected included presenting signs and symptoms, the hospital follow up for all children who returned within 10 days, test results, and telephone follow up. Results : The number of children referred to the emergency department was 7442, with 399 (5.4%) of these having acute abdominal pain. The mean age of the study population was 6.9 ± 3.5 years, and 201 of the patients were male. The five most prevalent diagnoses were: (i) upper respiratory tract infection and/or complicated with otitis media or sinusitis (23.7%); (ii) abdominal pain with uncertain etiology (15.4%); (iii) gastroenteritis (15.4%); (iv) constipation (9.4%); and (v) urinary tract infection (8%). The most common associated symptoms were decreased appetite, fever and emesis. Because of follow‐up deficiency the progress of 28 patients was not obtained. Eighty‐two children were referred to the department of pediatric surgery, but only 17 of 82 (20.7%) required surgical intervention (15 of these 17 for appendicitis). Eleven patients returned within 10 days for re‐evaluation, but the initial diagnosis was not changed. The complaints of 57 patients with uncertain etiology were resolved within 2 days. Conclusions : An acute complaint of abdominal pain was usually attributed to a self‐limited disease. However, the percentage of surgical etiology is not negligible.  相似文献   
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OBJECTIVE: To compare measured glomerular filtration rate (GFR) by single plasma sample methods (SPSMs), gamma camera Gates, 24-h endogenous creatinine clearance, and prediction equations (Cockcroft-Gault and modification of renal disease (MDRD)) with the two plasma sample method (TPSM) considered as the reference in potential kidney donors with normal renal function. METHODS: One hundred and fifteen subjects (50 male, 65 female; mean age 41.9+/-12.2 years) with normal renal function were prospectively included in this study. GFR was calculated by TPSM (120-min and 240-min samples) and SPSM (180-min sample). RESULTS: While there was strong statistically significant correlation between the TPSM and all SPSMs, low correlation was found in Gates, creatinine clearance, Cockcroft-Gault and MDRD. In all SPSMs, 95% limits of agreements were consistent with each other and within clinically acceptable limits. The lowest bias, median absolute difference, mean percentage error, and the best precision were found for Christensen and Groth's method as modified by Watson (CGmW). CONCLUSIONS: Among the SPSMs, CGmW can reflect GFR more accurately than the other methods. Neither the gamma camera Gates method nor the creatinine clearance method nor the prediction equations (Cockcroft-Gault and MDRD) could calculate GFR accurately. All these techniques could result in mistakes in the management of potential kidney donors.  相似文献   
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