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131.
Our aim was to evaluate whether adenotonsillar hypertrophy (ATH) is associated with rheumatic heart disease (RHD) in children. Fifty-three patients with ATH and 50 healthy children as a control group were enrolled in the study. Medical history and clinical findings were investigated, and echocardiographies were done by researchers who were unaware of the diagnosis. The two groups were compared. Valvular findings suggesting RHD were encountered in four patients (7.5%) in the ATH group and in two children (4%) in the control group. This difference was not statistically significant (p = 0.098); however, we found physiological mitral regurgitation to be significantly more frequent in the ATH group than in the control group (p = 0.023). ATH did not increase the risk of valvulitis related to RHD regardless of adenoid size and frequency of the infection. To preclude the misdiagnosis of mitral regurgitation that results from RHD, diagnostic criteria for pathological mitral regurgitation should be carefully applied.  相似文献   
132.
Besides suppressing sebum production, the exact mechanism of action of isotretinoin in acne vulgaris is not known. Several hormones have been linked to the pathogenesis of acne. In this study, we investigated the effects of isotretinoin on the pituitary-adrenal axis, whose activity may be increased in acne. Various hormone systems were evaluated before and after 3 months of isotretinoin treatment in 47 acne patients. Free triiodothyronine (T3), thyroid-stimulating hormone and thyroid-stimulating hormone receptor antibody levels decreased significantly during isotretinoin treatment (p?相似文献   
133.
Isotretinoin is an effective therapy for severe nodulocystic acne. Several experimental studies suggest that it may have an effect on vitamin D physiology. In the present study, the authors aimed to investigate the effect of isotretinoin treatment on the metabolism of vitamin D in acne patients. A prospective analysis of 50 consecutive acne patients who were treated with isotretinoin for 3 months was done. Before and after 3 months of treatment, 25 hydroxy vitamin D, 1,25 dihydroxy vitamin D, and bone alkaline phosphatase, calcium, phosphate, and parathormone levels were measured. The 25 hydroxy vitamin D and serum calcium levels decreased significantly (p < 0.0001, p < 0.05, respectively), whereas 1,25 dihydroxy vitamin D, parathormone, and bone alkaline phosphatase levels increased significantly after 3 months of isotretinoin treatment (p < 0.005, p < 0.005, p < 0.0001, respectively). Aspartate aminotransferase, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels also increased significantly after isotretinoin treatment. This prospective clinical study showed that isotretinoin has an effect on vitamin D metabolism. Further clinical studies with longer periods of follow-up are needed to understand the effect of isotretinoin on vitamin D and bone metabolism.  相似文献   
134.
Hypertrophic osteoarthropathy (HOA) is characterized by clubbing, periosteal new bone formation and polyarthritis. The pathogenesis of clubbing involves an increased expression of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) from the digitally lodged platelet clumps, which bypass the pulmonary capillary network as a result of various systemic disorders. Intrathoracic neoplasms are rare causes of HOA in children. We report here a 14-year-old boy with digital clubbing, who eventually received the diagnosis of intrathoracic Hodgkin lymphoma (HL) and HOA. Eight cases previously reported with these two diagnoses are reviewed to emphasize the prognostic significance of HOA in childhood HL. Conclusion: Given the pathogenesis of clubbing and the prognostic significance of HOA, intrathoracic disease should be considered when HOA is detected in a child with a known or suspected malignant disease, and the occurrence of HOA during follow-up should alert the physicians for possible recurrence of the neoplastic disease or intrathoracic involvement. There is no conflict of interest associated with this report nor any sponsors.  相似文献   
135.
Objective: The purpose of this study was to correlate the histological diagnosis made during intraoperativefrozen section (FS) examination of hysterectomy samples with complex atypical endometrial hyperplasia (CAEH)diagnosed with definitive paraffin block histology. Methods: FS pathology results of 125 patients with a preoperativebiopsy showing CAEH were compared retrospectively with paraffin block pathology findings. Results:Paraffin block results were consistent with FS in 78 of 125 patients (62.4%). The FS sensitivity and specificityof detecting cancer were 81.1% and 97.9%, with negative and positive predictive values of 76.7%, and 98.4%,respectively. Paraffin block results were reported as endometrial cancer in 77 of 125 (61.6%) patients. Finalpathology was endometrial cancer in 45.3% patients diagnosed at our center and 76.9% for patients who hadtheir diagnosis at other clinics (p=0.018). Paraffin block results were consistent with FS in 62.4% of all casesConsistence was 98.4% in patients who had endometrial cancer in FS. Conclusion: FS does not exclude thepossibility of endometrial cancer in patients with the preoperative diagnosis of CAEH. In addition, sufficientendometrial sampling is important for an accurate diagnosis  相似文献   
136.
The authors investigated the diagnostic value of cerebrospinal fluid (CSF) soluble CD27 (sCD27) for leptomeningeal involvement of non-Hodgkin lymphomas (NHL). Cytospin slides were prepared from CSF samples of 64 children treated for NHL. sCD27 levels were determined by sandwich ELISA method using two CD27 monoclonal antibodies. 8/194 (4.1%) samples were considered tumor-positive by cytology. Mean sCD27 values were 5.8 and 13.8 U/mL in tumor-negative and tumor-positive samples, respectively (p =.18). 26/194 samples were false positive and 2/194 false negative (cutoff: 7 U/mL) (sensitivity, 75%; specificity, 86%; positive predictive value, 18.8%; negative predictive value, 98.8%; accuracy, 85.6%). With these results, the value of adding sCD27 determination to the cytological CSF examination remains questionable.  相似文献   
137.
138.
In this study, the aim was to assess the in vitro apical microleakage of a resin-based sealer used with two different adhesives. Thirty nine freshly extracted maxillary incisors were used. The teeth were decoronated at the cemento-enamel junction with a water-cooled fissure bur. Chemo-mechanical debridement of the root canals was accomplished with the step-back technique. The smear layer was removed by 19% ethylenediamine tetra acetic acid (EDTA). The roots were then divided into three experimental groups of thirteen teeth in each. Specimens in group 1 were filled with gutta-percha, AH Plus sealer, and water-based adhesive system (Syntac Single Component). Group 2 specimens were filled with gutta-percha, AH Plus sealer, and acetone-based dentin adhesive (Prime & Bond NT ). Specimens of group 3 were filled with only gutta-percha and AH Plus sealer (no adhesive was applied). The teeth were immersed into 2% methylene blue solution. Apical sealing qualities were assessed by measuring the linear dye penetration with a stereomicroscope. Dentin tubule penetration was observed under scanning electron microscopy (SEM). Results showed no statistically significant difference between the materials used, however, the leakage in group 2 was less than group 1 and 3.  相似文献   
139.
Olfactory neuroblastoma, a rare malignancy of the olfactory epithelium, is an uncommon tumor in children. It occurs mostly in older individuals and the treatment strategies are based on the experience with adults. In this report, clinical characteristics and treatment results of 2 patients with olfactory neuroblastoma are described and discussed with those reported in the literature.  相似文献   
140.
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