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Abstract – In the treatment of crown fractures, adhesive fragment reattachment provides a good alternative to other restorative techniques, offering several advantages. The present paper reports a case in which the treatment of a cervical crown fracture was accomplished by reattaching the tooth fragment with a flowable resin composite. Orthodontic root extrusion was performed with a modified Hawley appliance prior to fragment reattachment. The clinical and radiographic results after 2.5 years were successful. 相似文献
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Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
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Sabri Acarturk Emrah Arslan Ferit Demirkan Sakir Unal 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(4):409-16; discussion 417-8
Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed. 相似文献
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An intelligent system for diagnosis of the heart valve diseases with wavelet packet neural networks 总被引:3,自引:0,他引:3
In this paper, an intelligent system is presented for interpretation of the Doppler signals of the heart valve diseases based on the pattern recognition. This paper especially deals with combination of the feature extraction and classification from measured Doppler signal waveforms at the heart valve using the Doppler Ultrasound. Because of this, a wavelet packet neural network model developed by us is used. The model consists of two layers: wavelet and multi-layer perceptron. The wavelet layer is used for adaptive feature extraction in the time-frequency domain and is composed of wavelet packet decomposition and wavelet packet entropy. The multi-layer perceptron used for classification is a feed-forward neural network. The performance of the developed system has been evaluated in 215 samples. The test results showed that this system was effective in detecting Doppler heart sounds. The correct classification rate was about 94% for abnormal and normal subjects. 相似文献
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In search of candidate genes critically expressed in the human endometrium during the window of implantation 总被引:17,自引:0,他引:17
Mirkin S Arslan M Churikov D Corica A Diaz JI Williams S Bocca S Oehninger S 《Human reproduction (Oxford, England)》2005,20(8):2104-2117
BACKGROUND: In this prospective randomized blinded clinical trial, we examined gene expression profiles of the human endometrium during the early and mid-luteal phases of the natural cycle. METHODS: An endometrial biopsy was performed on day 16 (LH +3) or on day 21 (LH +8), followed by RNA extraction and microarray analysis using an Affymetrix HG-U95A microchip. Data analysis was carried out using pairwise multiple group comparison with the significance analysis of microarrays (SAM) software. RESULTS: With a false discovery rate of 0, the analysis revealed that 107 genes were significantly and differently expressed (> or =2-fold) during the early versus the mid-luteal phase of the cycle. Forty-five of these genes have not been previously linked to endometrial receptivity. Validation of the microarray data was accomplished using semiquantitative RT-PCR. We demonstrated the presence of estrogen and progesterone response elements (ERE and PRE) by analysis of the 5'-flanking regions of a subset of differentially regulated genes. CONCLUSIONS: Using a strict bioinformatics approach of microarray data, we demonstrated significant changes in candidate genes during the transition of the early to the mid-luteal phase of the human endometrium that may have functional significance for the opening and maintenance of the window of implantation. 相似文献
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Ertunc D Aban M Tok EC Tamer L Arslan M Dilek S 《Human reproduction (Oxford, England)》2005,20(8):2157-2161
BACKGROUND: Glutathione-S-tranferase (GST) is the part of the key phase II detoxifying enzyme system. Many studies have investigated the role of GSTM1 and GSTT1 gene polymorphisms in endometriosis. Although GSTP1 was found to be one of the most abundant types of GST in genital system, there are insufficient data about the importance of the role of GSTP1 gene polymorphism in endometriosis. METHODS: This case-control study involved 150 patients with endometriosis and 150 controls. The frequency of GSTP1 single nucleotide polymorphisms was evaluated using PCR and melting curve analysis. RESULTS: The proportion of GSTP1 ile/ile tended to be higher in patients with endometriosis than control group, although the difference was not significant [odds ratio (OR)=1.53; 95% confidence interval (CI)=0.95-2.46]. In contrast, GSTP1 val/val was significantly higher in control patients and seems protective for endometriosis (OR=0.10; 95% CI=0.02-0.42). CONCLUSION: The results of this study suggest that GSTP1 polymorphism might modulate the risk of endometriosis with significantly decreased risk for GSTP1 val/val and marginally increased risk for GSTP1 ile/ile. Further studies on not only the disease processes but also normal distribution of the enzyme in female genital tract may provide better understanding about the role of GST types and their polymorphs in endometriosis. 相似文献
8.
Gungor E Eroglu Felicia A Rabito Sudesh K Srivastav 《Annals of allergy, asthma & immunology》2002,89(2):191-194
BACKGROUND: Asthma mortality rates have been increasing despite our improved understanding of the pathophysiology of asthma and advanced methods of treatment. Although there are many national studies of asthma mortality rates, few studies have concentrated on subnational regions such as individual states. OBJECTIVES: We sought to determine the trends in asthma mortality in children and young adults during the last 15 years in Louisiana. METHODS: Asthma mortality data were acquired from the Louisiana State Center for Health Statistics for the years 1983 through 1997. All asthma deaths coded International Classification of Disease, Ninth Revision 493 were included in the data set along with year, sex, and rate characteristics. State population estimates obtained from the United States Bureau of Census for three 5-year periods (1983 to 1987, 1988 to 1992, and 1993 to 1997) were used to calculate crude and adjusted mortality rates. These time periods were compared with one another and with the period 1983 to 1987, which was used as a baseline. RESULTS: For all residents, the mortality rate increased from 0.41 deaths per 100,000 persons during the 1983 to 1987 time period to 0.49 and 0.63 deaths per 100,000 persons during 1988 to 1992 and 1993 to 1997 time periods, respectively. Mortality rates have increased in both the white and non-white populations over the 15-year study period, with the most pronounced increases among the non-white population. CONCLUSION: Asthma mortality rates in Louisiana have increased, particularly among the non-white population, over the last 15 years, although the results are not statistically significant. When compared with other states, asthma mortality in Louisiana is lower than in the northeast and central north states. 相似文献
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