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21.
OBJECTIVE: The aim of this study was to determine the syndromic etiology of bilateral severe sensorineural hearing disorders in children and current etiological causes to reduce the cases in the unknown group. METHODS: This study was conducted on 550 students of five schools for the deaf in Istanbul and Zonguldak, Turkey. Otologic, audiologic, dysmorphologic, ophthalmologic and dental examinations were performed in all children. Familial and medical histories were obtained. RESULTS: The etiology of hearing loss was genetic in 346 (62.90%), acquired in 107 (19.45%) and unknown in 97 (%17.63) cases. A total of 619 malformations were defined in 550 children and 99 of them belonged to a syndrome. We identified 33 different syndromes for these 99 syndromic children. Syndromic etiology was found in 18.0% of the total and 28.61% of the subjects with genetic etiology. Most common syndrome was Waardenburg syndrome which occurred in 33 children. CONCLUSION: The incidence of hereditary hearing impairment is very high in developing countries compared to developed countries. Prevention is essential to reduce the incidence, multidisciplinary approach and genetic counselling are necessary in this regard.  相似文献   
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OBJECTIVE: The etiology of deafness can be classified as genetic, acquired and unknown. An unknown etiology was a high incidence in previous reports. The aim of this study is to explore the etiology of deafness and to reduce the cases in the unknown group. METHODS: This study was conducted on 162 students at the Yeditepe School for the deaf. Otologic, physical and psychological examinations were performed by a team of doctors including four otologists, a geneticist, a dentist, an ophthalmologist and an audiologist. RESULTS: A genetic cause was identified in 41.35%, acquired 37.65% and unknown 20.98%. Genetic etiologies were stratified as familial and syndromic subgroups. A familial cause was found in 60 of 162 children and in 22 of those 60 cases, the parents had a consanguineous marriage. There was 11 cases associated with a syndrome. Ninety four minor abnormalities have been established in some deaf children. Febrile convulsion (36%) was identified as the most common etiology in acquired cases. CONCLUSION: In contrast with other studies the consanguineous marriage was present in 36.6% of the familial cases and 38.8% in total of the school. An unknown etiology was reported in high rates in previous reports. These unknown cases could be described as a part of a syndrome by a crowded team of consultants. Evaluation of early diagnostic criterias and minor abnormalities can help us to provide early rehabilitation of deafness in childhood.  相似文献   
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Management of Esophageal Perforation   总被引:12,自引:0,他引:12  
Despite recent advances in thoracic surgery, the management of esophageal perforation remains problematical and controversial. Thirty-one patients were treated for an esophageal perforation between 1986 and 1998. The esophageal perforation was iatrogenic in 25 cases, spontaneous in 2, traumatic in 2, and caused by a tumor and tuberculous lymphadenitis in 2 patients. There were 10 cervical, 19 thoracic, and 2 abdominal perforations. The interval from perforation to operation was less than 24 h in 12 patients and more than 24 h in 19 patients. The surgical procedures included a primary repair in 12 patients, a resection in 8, and conservative treatment with minor surgical approaches in 11. The mortality rate was 20% (4/20 patients) in the surgical treatment group and 45.5% (5/11 patients) in the conservative treatment with minor surgery group. The overall mortality was 29% (9/31 patients). The prognosis is thus concluded to depend on the cause and location of the perforation, the presence of underlying esophageal diseases, and the surgical procedure chosen. Received: October 12, 1999 / Accepted: May 30, 2000  相似文献   
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Bio-implants in the human body act as passive surfaces that are prone to bacterial adhesion potentially leading to deep body infections. Pedicle screws made of uncoated or silver-coated titanium alloy were used both in vitro and in vivo to determine whether silver-coated materials have antimicrobial properties when they are anodized. Twenty-four New Zealand Albino rabbits were divided into four groups with six in each. In Group 1, the rabbits were exposed to 8 muA direct current (DC) via silver-coated screws. In Group 2, the rabbits were not exposed to any electrical current, but silver-coated screws were used. In Group 3, the rabbits were exposed to 8 muA DC using uncoated screws. In Group 4, the rabbits were not exposed to any electrical current, but uncoated screws were used. Staphylococcus aureus (106 cfu) was inoculated into the rabbits before any electrical current was applied. All the animals were killed, and the areas surrounding the screws were histologically and microbiologically examined. Silver-coated titanium screws prevented implant-associated deep bone infections when they were polarized anodically. The antibacterial effects of the same screws with the same bacterium were confirmed in in vitro experiments on agar plates. When the screws were anodized with the same electrical parameters in vitro, a marked inhibition zone was detected around the silver-coated screws but not around the uncoated screws. Our findings suggest that silver-coated titanium implants can be used to prevent implant-associated deep bone infections when they are polarized anodically.  相似文献   
26.
INTRODUCTION: Programmable pacemaker sensor features are frequently used in default setting. Limited data are available about the effect of sensor optimization on exercise capacity and quality of life (QOL). Influence of individual optimization of sensors on QOL and exercise tolerance was investigated in a randomized, single blind study in patients with VVIR, DDDR, or AAIR pacemakers. METHODS: Patients with > or =75% pacing were randomized to optimized sensor settings (OSS) or default sensor setting (DSS). Standardized optimization was performed using three different exercise tests. QOL questionnaires (QOL-q: Hacettepe, Karolinska, and RAND-36) were used for evaluation of the sensor optimization. One month before and after optimization, exercise capacity using chronotropic assessment exercise protocol and the three QOL-q were assessed. RESULTS: Fifty-four patients (26 male, 28 female) with a mean age of 65 +/- 16 years were enrolled in the study. In each group (OSS and DSS) 27 patients were included. One month after sensor optimization, the achieved maximal heart rate (HR) and metabolic workload (METS) were significantly higher in OSS when compared with DSS (124 +/- 28 bpm vs 108 +/- 20 bpm, P = 0.036; 7.3 +/- 4 METS vs 4.9 +/- 4 METS, P = 0.045). Highest HR and METS were achieved in patients with pacemakers with accessible sensor algorithms. In patients with automatic slope settings (33%), exercise capacity did not improve after sensor optimization. QOL did not improve in OSS compared with DSS. CONCLUSION: After 1 month of individual optimization of rate response pacemakers, exercise capacity was improved and maximum HR increased, although QOL remained unchanged. Accessible pacemaker sensor algorithms are mandatory for individual optimization.  相似文献   
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Chronic hepatitis C virus (HCV) has extrahepatic autoimmune properties and a variety of autoantibodies were found in patients with HCV. Patients with HCV infection may have rheumatic symptoms and signs, and 50–70% of the cases may contain rheumatoid factor (RF). The increased prevalence of RF in patients with HCV infection diminishes the diagnostic specificity of serum RF for rheumatoid arthritis (RA) in patients with HCV. Therefore, the presence of RF mostly does not help in distinguishing between RA and HCV-associated rheumatic symptoms. In this study, we studied whether cyclic citrullinated peptide (CCP) antibody, a highly specific biomarker for RA in the general population, was useful for the diagnosis of RA in nonarthritic patients with HCV (hepatitis C virus). Blood samples from 39 patients with chronic HCV infection, 87 normal sera from volunteer blood donors and 108 blood samples from patients with rheumatoid arthritis, from the rheumatology clinic, were taken. RF was measured using the Dade-Behring nephelometer and antibodies to CCP were measured with ELISA. According to statistical analysis, the sensitivity, specificity and positive predictive value of the anti-CCP test was superior to the RF test. Cyclic citrullinated peptide antibody is a more useful test than RF among patients with chronic HCV infection without arthritis.  相似文献   
29.
Extramedullary plasmacytomas are rare tumors. In majority of cases tumors arise in the head and neck region and endobronchial localization is extremely rare. The treatment is usually resection alone or combination of surgery with radiotherapy. Herein we present a case of solitary endobronchial plasmacytoma which was resected with bronchoscopic electrocautery, because of extremely rare occurrence of solitary endobronchial plasmacytoma and also the successful outcome of bronchoscopic electrocautery therapy.  相似文献   
30.
Zinc is an important trace element in biological systems; however, excessive extracellular zinc could lead to neuronal cell death following ischemia, seizures, and brain trauma. In this study, we investigated whether the intracortical injection of zinc sulphate (200 μg/kg, i.c.) changes total number of Purkinje cells in the cerebellum and whether different types nitric oxide synthase inhibitors, N-(G)-nitro-L-arginine methyl ester (L-NAME), N(omega)-nitro-L-arginine (L-NNA), aminoguanidine and 7-nitroindazole (7-NI), have protective effects against zinc neurotoxicity in Wistar albino rats. Animals were divided into 6 groups: control, zinc, zinc+L-NAME (100 mg/kg, i.p.), zinc+L-NNA (100 mg/kg, i.p.), zinc+7-NI (100 mg/kg, i.p.) and zinc+aminoguanidine (100 mg/kg, i.p.) groups. Total number of Purkinje cells in the cerebellum was estimated using unbiased stereological technique as 318,947 ± 20,549, 123,483 ± 23,762, 206,537 ± 43,128, 178,135 ± 26,635, 193,148 ± 46,104 and 212,910 ± 26,399 in the control, zinc, zinc+L-NAME, zinc+L-NNA, zinc+7-NI and zinc+aminoguanidine groups, respectively (mean ± SD). The number of Purkinje cells in zinc group was significantly lower than that of the other groups (P<0.001). It was found that the nitric oxide synthase inhibitors have neuroprotective effect against zinc neurotoxicity on Purkinje cells. These data show that the inhibition of the nitric oxide synthase could prevent some of the deleterious effects of zinc on Purkinje cells.  相似文献   
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