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991.

Objectives  

The aim of this study was to determine the prevalence and characteristics of pneumatized articular eminence (PAE) in dental patients using cone beam computed tomography (CBCT) with respect to age, sex, and type of skeletal anomaly. The results were then compared to prevalence studies regarding PAE in the literature.  相似文献   
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PURPOSE: The objectives of this study were to determine the levels of lifetime cigarette use, daily use, and current use among young people (aged 15-19 years) and to examine the risk factors contributing to regular smoking. METHODS: The number of students was determined proportionately to the numbers of students in all the high schools in the province of Trabzon in Turkey. The data were gathered using the questionnaire method. A total of 4666 students participated in the study. The chi-square test and logistic regression analysis were used in data analysis. RESULTS: Of the 4666 students who took part in the study, the level of lifetime cigarette use was 38.2% (n = 1796), that of lifetime daily cigarette use was 10.5% (n = 491), and that of current cigarette use was 9.5% (n = 447). Male students (P < .0005), those whose mothers were smokers (P < .0005), those whose fathers smoked (P = .005), those whose siblings smoked (P<.0005), those whose friends smoked (P < .0005), those whose teachers smoked (P = .001), and low achievers in school (P < .0005) stated that they significantly smoked on a more regular basis. According to the results of the logistic regression analysis, the following risk factors were statistically significant: male students smoked 3.02 times (95% CI 2.20-4.16) more than females, those whose mothers were smokers smoked 1.57 times (95% CI 1.09-2.28) more than those whose mothers were not, those whose friends were smokers smoked 2.42 times (95% CI 1.73-3.39) more than those whose friends were non-smokers, poor achievers in school smoked 2.62 times (95% CI 1.97-3.49) more than high achievers, and those without poor grades smoked 1.75 times more (95% CI 1.23-2.40), the risk rising 1.06 times (95% CI 1.01-1.11) with earlier age at first experimentation. The risk of daily cigarette use was observed to decline by 0.91 times (95% CI 0.84-0.98) with increasing numbers of siblings. CONCLUSION: Effective smoking prevention programs should take into account the dominant influence of peer groups in the onset and continuation of smoking.  相似文献   
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998.

Objectives

The aim of the study is to assess the effect of ring wearing and ring types on hand contamination and efficacy of alcohol-based hand disinfection among nurses working in intensive care settings.

Methods

Hand cultures were obtained from 84 nurses providing direct patient care in intensive care units of a pediatric hospital. Colony counts were compared depending on ring wearing and the type of ring worn. Twenty-eight nurses were asked to a wear plain wedding ring, 28 to wear rings with stones and 28 not to wear any rings, starting 15 days before and continuing throughout the study. Cultures were obtained by using sterile gloves containing phosphate-buffered-saline solution (PBS) after an alcohol-based hand disinfectant was used and bacteria were identified with standard laboratory tests.

Results

The nurses wearing rings had more Gram-positive, Gram-negative and total bacterial colonization on their hands than the nurses without rings despite using an alcohol-based rub (p = 0.001). When comparing the two groups with rings (plain wedding rings and rings with stones), colony counts of Gram-positive, Gram-negative and total bacteria did not differ (p > 0.05).

Conclusions

Ring wearing increases the bacterial colonization of hands and alcohol-based hand disinfection might not significantly reduce contamination of the ring-wearing hands. The type of ring did not cause any significant difference on the bacterial load. Wearing rings could increase the frequency of transmission of potential nosocomial pathogens.  相似文献   
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Placental mesenchymal dysplasia (PMD) is a rare placental abnormality with sonographic and macroscopic features similar to those seen in a partial hydatidiform mole, and which has usually been reported with a normal female karyotype. We report a case of prenatally suspected PMD associated with trisomy 13. Sonography performed at 17 weeks' gestation showed multiple cystic spaces in the placenta resembling molar tissue, and a fetus with postaxial polydactyly and an atrial septal defect. An amniocentesis revealed a fetal karyotype of 46,XY,der(13), t(13;13)(q11;q11)[20]/47,XY,+13[11], consistent with trisomy 13. Cordocentesis confirmed the cytogenetic diagnosis. Histopathologic examination of the placenta following termination of the pregnancy at 22 weeks' gestation showed enlarged stem villi with loose connective tissue and cistern formation and no evidence of trophoblastic hyperplasia or stromal trophoblastic inclusions, which was consistent with PMD. PMD should be considered in the differential diagnoses of a placenta showing multiple cystic lesions on prenatal sonography, and karyotypic analysis should be performed.  相似文献   
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