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991.
Objective
Polycystic ovary syndrome (PCOS) is an endocrinopathy characterized by chronic anovulation and hyperandrogenism. Hormonal changes can affect hearing loss and inner ear functions. We evaluated hearing loss with audiometric tests in young patients with PCOS.Methods
Twenty-six women having PCOS and 25 normal individuals were enrolled in the study. Age ranges for PCOS and control groups were 20–35 years. Hormonal and biochemical values including LH, LH/FSH, E2, testosterone, fasting glucose and fasting insulin were calculated. Each subject was tested with low- (250–2000 Hz) and high-frequency audiometry (4000–8000 Hz). For each set of tests, mean values of air conduction at each frequency were measured for the PCOS and control groups and compared.Results
No difference was observed in speech frequencies on audiologic tests between the groups, however high-frequency hearing loss were significantly higher (p < 0.05) in PCOS patients than in control women. Also, hearing thresholds were normal range in all of frequencies in PCOS and control subjects. PCOS patients showed high levels of LH, LH/FSH, testosterone and fasting insulin.Conclusion
Our findings suggest that patients diagnosed with PCOS should be advised audiologic evaluation especially in the high frequency. 相似文献992.
993.
Tc-99m methoxyisobutylisonitrile (MIBI) scintigraphy is generally used as a second-line diagnostic tool for obscured breast lesions. When the entire field of view is examined carefully, it is often possible to detect additional lesions unrelated to the initial intent and purpose of the examination. Herein we present a case of breast cancer incidentally detected by cardiac Tc-99m MIBI scintigraphy. An area of uptake was detected in the breast during a cardiac imaging test. Further evaluation of this lesion revealed a histopathological diagnosis of invasive ductal carcinoma of the breast. Sensitivity of this scintigraphic technique is not enough sufficient to use this test as a screening test for breast cancer, but it may provide supplemental information. Since it is not uncommon to find incidental lesions during imaging studies, examination of the image field may help clinicians find otherwise unrecognized or undiagnosed pathologies. 相似文献
994.
995.
Bilhan H 《The Journal of oral implantology》2008,34(1):47-51
Several treatment options with implants have been described for maxillary edentulous patients. Maxillary implant-supported overdentures have been shown to be a predictable, accepted treatment option for the edentulous maxilla. Patients with severe bone resorption present additional difficulties, and implant treatment in the atrophic maxilla represents a challenge. Anatomical limitations and patient desires in this case have forced the treatment to be 4 angulated implants supporting an upper overdenture. Since conventional single-retention mechanisms such as ball (O-ring), locator, or telescopes would transfer too much force to the implants, especially because of their angulation, an individual bar was fabricated. One-year follow-up of the case showed a stable peri-implant condition on bone as well as soft tissue level. Although further follow-up and higher case numbers will give more information about this treatment modality, the actual result is encouraging and can be recommended for similar cases. 相似文献
996.
In this study, the effects of cervical headgear (CHG) use on the transverse dimension of the maxillary dental arch were evaluated in patients in the permanent dentition. Thirteen girls and 12 boys (mean age: 13.41 +/- 0.52 years) with a bilateral full cusp Class II molar relationship comprised the study group. Fifteen girls and 10 boys with a Class I normal occlusion comprised the controls. In the treatment group, CHG with an expanded inner bow was used for a mean period of 11.2 +/- 5.6 months. The headgear was used for molar distalization and the force magnitude was 196.1 cN. After CHG treatment, the patients underwent non-extraction fixed orthodontic treatment for 14.1 +/- 2.5 months. During this period, the control group received regular dental check-ups. Dental casts obtained at the beginning (T1) and end (T2) of headgear use and at the end of orthodontic treatment (T3) and posteroanterior cephalograms taken at T1 and T2 were evaluated. A Student's t-test was used for intergroup comparison at T1, T2, and T3 and a Mann-Whitney U-test with a Bonferroni correction for comparison of treatment/observation changes. At T2, intercanine (0.96 +/- 0.56 mm), interpremolar (1.6 +/- 0.55 mm for the first premolar, 1.74 +/- 0.65 mm for the second premolar), and intermolar (2.31 +/- 0.75 mm) widths increased, while the distance between the intersection of the zygomatic process and the maxillary alveolar process on the right (JR) and left (JL) did not change. Fixed orthodontic treatment did not have any effect on any of the measurements. With the intentional expansion of the inner bow of CHG, the amount of maxillary dental arch expansion achieved in the permanent dentition was statistically significant (P < 0.017). 相似文献
997.
The objective of the present investigation was to determine the intrapulpal temperature changes and to compare the shear bond strength (SBS) of bondable buccal tubes bonded by high-intensity light sources. Ninety caries-free human first molar teeth extracted for periodontal reasons were used. For the temperature measurement test, 30 teeth were randomly divided into three groups (n = 10) whereas 60 teeth were used in three groups (n = 20) for SBS testing. Three light sources, high-intensity halogen, blue light-emitting diode (LED), and xenon plasma arc (PAC), were used for polymerization of Transbond XT. Temperature variations (Delta T) were recorded by a K-type thermocouple wire connected to a data logger. For SBS testing, a universal testing machine was used at a crosshead speed of 1 mm/minute until buccal tube bonding failure occurred. Data were analyzed using the Kruskal-Wallis test. The high-intensity halogen light resulted in significantly (P < 0.01) higher intrapulpal temperature changes than the LED or PAC. The results of the shear bond test revealed significant (P < 0.05) differences only between the halogen and LED groups. The findings of the present investigation showed that high-intensity curing devices can safely be used in bonding buccal tubes to molar teeth without causing a deleterious effect on the dental pulp. 相似文献
998.
The effects of dentin and cement thicknesses on stress level and distribution of crack propagation in ceramic-cement-dentin multilayer complex were analyzed. Custom-designed finite element analysis program based on JL Analyzer was used to analyze the stress distribution and present the maximum principal stress locations. In Zirconia, all the maximum stress values were above 100 MPa. In Empress II, they ranged between 50 and 105 MPa, which were approximately one-third of those of Zirconia. In Feldspathic, the maximum stress values were generally lower than 50 MPa. In all groups with 30 microm cement thickness, the highest values were observed at the bottom surface. For cement thicknesses at 50, 70, and 100 microm, maximum stress was found to occur at the top surface. However, changes in dentin thickness did not bring about significant changes in maximum stress values. Results of this study revealed the roles played by the following variables in the failure of a multilayer structure: cement thickness had a minor influence, dentin thickness exerted no influence, but the thickness and type of ceramic system played a significant role. 相似文献
999.
1000.