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The aim of this study was to evaluate changes in nasal and oropharyngeal flora in patients with acne during treatments with tetracycline and isotretinoin. Swab specimens were taken from the right and left nasal cavities and oropharynx of 55 patients with acne and 20 healthy volunteers who were admitted to the dermatology department (Etlik Educational and Research Hospital, Ankara, Turkey) before the administration of treatment and in the third month of treatment. Study participants were divided into four groups as follows: patients with acne on topical treatment only, systemic isotretinoin, and systemic tetracycline, and the control group. Of 55 patients with acne, 18 were male and 37 were female. The mean age of the patients and the control group was 22.21 ± 4.22 and 21.95 ± 7.64, respectively. Staphylococcus aureus was isolated from the nasal flora of five patients, normal flora was suppressed in the oropharyngeal cultures of seven patients, and normal flora grew in the cultures of the other 20 patients who were on tetracycline treatment. On the other hand, normal flora grew in the nasal and oropharyngeal cultures of all the patients who were on isotretinoin treatment. Treatment options and follow‐up procedures for acne vulgaris may lead to the development of bacterial resistance and damage to flora. In particular, systemic tetracycline treatment leads to changes in flora of the nose and throat in patients with acne with an increased carriage of S. aureus. Therefore, careful attention should be paid to the duration of tetracycline treatment in order to not increase the risk of disturbance of microbial flora.  相似文献   
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Since the identification of nitric oxide (NO) as an endothelial-derived relaxing factor, it became very important to quantify NO in biological models eventhough it is present in very low concentrations with a very short half-life. The use of electrochemistry as an alternative detection method is quite promising and electrochemical probes are now being developed to detect NO. This paper consists of an amperometric, bi-polymer modified, platinum-iridium microelectrode (Pt 90%-Ir 10% alloy, multistranded, total diameter 130 microm) design and its application for NO detection in acetylcholine (Ach) introduced, rabbit isolated carotid artery endothelium model. In a pH range of 3.0-10.0. pH 3.0 was found to be the optimum pH. As the pH values increased up to 10.0, the response current decreased as the oxidation of NO is catalyzed by H(+) in the acidic media. Temperature effect was checked at 25 degrees C (room temperature), 30 and 40 degrees C. An increasing trend was observed in sensor response with the increasing temperature. Most common biological interferences as ascorbic acid, uric acid and glucose were eliminated via bi-polymer coatings of four layers of Nafion and a layer of 50 mM o-phenylenediamine (OPD). When S/N ratio was accepted as 3, limit of detection was calculated as 15 nM. NO release from carotid artery endothelium was also determined by measuring response force in thermostatic isolated organel baths. Obtained force responses (mg) were compared with the electrochemical (nA) sensor responses.  相似文献   
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Anticholinesterase poisoning is an important health problem in our country, and a complete understanding of its underlying mechanisms is essential for the emergency physician. Thus, we aimed to investigate the cardiac biochemical parameters and mortality in dichlorvos-induced poisoning in rats. Rats were randomly divided into 5 groups as control (corn oil), dichlorvos, atropine, pralidoxime, and atropine+pralidoxime groups. Immunohistochemical analyses of apoptosis and inducible nitric oxide synthase showed no change in cardiac tissue for all of the groups. Serum cholinesterase levels were suppressed with dichlorvos, and these reductions were inhibited with atropine and/or pralidoxime pretreatment. Serum levels of creatine kinase, creatine kinase-MB, cardiac troponin I, myoglobin, and N-terminal probrain natriuretic peptide were not affected with poisoning. Malondialdehyde and glutathione levels were not statistically significant between the groups. Although serum nitric oxide levels in the dichlorvos group were lower than those in the control group, cardiac nitric oxide levels in the atropine+pralidoxime group were markedly higher than those in the dichlorvos group. Atropine, pralidoxime, and atropine+pralidoxime pretreatments markedly reduced the mortality. In conclusion, our results implied that measured cardiac markers especially N-terminal probrain natriuretic peptide may not contribute to the early (first 6 hours) diagnosis of cardiotoxicity in dichlorvos-induced poisoning in rats. These results also showed that acute dichlorvos administration did not cause significant cardiac damage, and oxidative stress does not play a marked role in dichlorvos-induced poisoning. Besides, cardiac nitric oxide may produce protective effect on myocardium with atropine+pralidoxime therapy in rats.  相似文献   
116.
Savas Erdeve S  Balta H  Balta Z  Dallar Y 《The Journal of pediatrics》2006,148(3):422; author reply 422-422; author reply 423
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117.
OBJECTIVE: Auditory neuropathy/auditory dyssynchrony (AN/AD) has become a well-accepted clinical entity. The combined use of oto-acoustic emissions (OAEs) and auditory brainstem response (ABR) testing in the universal newborn hearing screening (UNHS) has led to the easy recognition of this disorder. Although, we are now able to diagnose AN/AD reliably, little is known about its epidemiology, etiology, and especially the frequency of its occurrence. The primary goal of this study was to determine the frequency of AN/AD in the Western Anatolian region of Turkey. The secondary goal was to compare the detection rate of AN/AD before and after the implementation of the UNHS in the audiology department of Dokuz Eylul University Hospital. METHOD: Between 2005 and 2007, among the 23,786 newborns who were screened by automated click evoked oto-acoustic emissions (a-CEOAE) and automated auditory brainstem responses (a-ABRs), 2236 were referred to our department. All necessary audiological tests were performed for all the referred newborns. Among them, babies with deficient or abnormal ABR in combination with normal OAEs were considered as having AN/AD. These babies were evaluated with additional diagnostic audiological tests. Furthermore, comparison of the incidence of children diagnosed with AN/AD before and after the implementation of UNHS in our audiology department was also performed. RESULTS: Among the referred newborns, 65 had abnormal or deficient ABR test results. Ten of these 65 newborn babies (mean diagnostic age: 5.7 months) with hearing impairment showed electrophysiological test results that were consistent with AN/AD. The frequency of AN/AD in these 65 children with hearing loss was 15.38%. Moreover, the frequency of AN/AD within UNHS was found to be 0.044%. Seven of the 10 babies with AN/AD had hyperbilirubinemia as a risk factor, which is a high rate to be emphasized. On the other hand, the retrospective investigation of children diagnosed with AN/AD in the same audiology department between 1999 and 2005 (i.e. before the implementation of UNHS) revealed only 7 children, with an average diagnostic age of 34 months. CONCLUSION: After implementing the UNHS, the incidence of AN/AD in the audiology department increased from 1.16 to 4.13. Furthermore, the age of diagnosis of AN/AD decreased from 34 months to 5.7 months. This study shows that AN/AD, when screened, is a comparatively common disorder in the population of hearing-impaired infants. While newborn hearing screening provides early detection of babies with hearing loss, it also helps to differentiate AN/AD cases when the screening is performed with both a-ABR and automated oto-acoustic emission (a-OAE) tests. Thus, the routine combined use of a-ABR and a-OAE tests in UNHS programs, especially for the high-risk infants, can provide better detection of newborns with AN/AD. Furthermore, hyperbilirubinemia is merely an association and maybe etiologically linked.  相似文献   
118.
The aim of this study was to elucidate the pathologic sequence changes and associated clinical phenotypes in 9 new patients showing homozygosity for perforin gene among a total of 37 (24%) Turkish FHL families studied by linkage analysis. These 9 unrelated patients (5M/4F) were coming from consanguineous families and their presentation ages of systemic symptoms were ranged from birth to 15 years. Direct sequencing of coding exons of the perforin gene led to the identification of five different homozygous alterations. The nonsense W374X mutation was identified in three patients while four different missense mutations namely G149S, V50M, A91V and novel A523D were detected in the rest six patients.  相似文献   
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