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Objective:To determine the total oxidant status (TOS), total antioxidant status (TAS), and the 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels and their interrelationship in the saliva of children undergoing fixed orthodontic therapy.Materials and Methods:Thirty children were randomly divided into three groups. The attachments were bonded to all of the teeth using three different orthodontic composites: Transbond XT, Kurasper F, and GrenGloo. The salivary levels of TOS, TAS, and 8-OHdG were determined three times, as follows: before treatment (T1) and at 1 month (T2) and 3 months (T3) following appliance placement. All data were statistically analyzed.Results:There were no significant differences in TOS, TAS, and 8-OHdG within the same time periods among the three different orthodontic composites (P > .05). TAS in all composite groups decreased over time. These decreases were found to be significant for Kurasper F and GrenGloo at the T1–T3 and T2–T3 time periods (P < .05). In all composite groups 8-OHdG decreased between T1 and T2 (P < .05). However, 8-OHdG in all composite groups increased from T2 to T3. These differences in 8-OHdG were significant in Kurasper F and GrenGloo (P < .05).Conclusions:Fixed orthodontic appliances bonded with the tested composites did not increase the cytotoxicity markers in saliva.  相似文献   
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Objective:Premature thelarche (PT) is defined as isolated breast development in girls before eight years of age. Gonadotropin-releasing hormone (GnRH) stimulation test is sometimes used to distinguish between PT and central precocious puberty (CPP), although the interpretation of the test at early ages is challenging. The objective of this study was to determine the follicle stimulating hormone (FSH) and luteinizing hormone (LH) responses to GnRH stimulation in girls with PT below 3 years of age.Methods:A standardized GnRH stimulation test, bone age and pelvic ultrasound were evaluated and those without pubertal progression after a minimum of one-year follow up were included in the study.Results:On GnRH stimulation test, the median (range) baseline LH was 0.29 (0.10-0.74) IU/L, baseline FSH was 4.96 (3.18-7.05) mIU/mL, and the peak median LH was 5.75 (3.31-8.58) IU/L with the peak mean±standard deviation FSH was 40.38±20.37 mIU/mL. Among the patients, 33.3% (n=10) had baseline LH >0.3 IU/L, 67% (n=20) had peak LH >5 IU/l and 16.6% (n=5) >10 IU/L. The mean peak LH/FSH ratio was 0.17±0.09 and was ≤0.43 in all participants.Conclusion:Although consensus statements usually define baseline LH >0.3-0.5 IU/L, peak LH >5 IU/L, and LH/FSH ratios >0.66-1.0 as diagnostic cut-offs for CPP, in children below 3 years of age, the baseline and peak LH values may be similar to pubertal values, possibly due to mini-puberty. A dominant FSH response on GnRH stimulation test is more valuable than the peak LH response in the diagnosis of PT.  相似文献   
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Xanthogranulomatous cholecystitis is a rare variant of chronic cholecystitis characterized by severe proliferative fibrosis and accumulation of lipid-laden macrophages in areas of destructive inflammation. The macroscopic appearance generally mimics a gallbladder carcinoma.

Twelve cases of xanthogranulomatous cholecystitis were identified from a retrospective analysis of the patient records of 770 cholecystectomy cases operated on in our department from January 1996 to October 2001. There were four men and eight women. Mean age of presentation was 52.5 years. Eleven patients had gallbladder stones. Seven patients had a history of acute cholecystitis and five patients of biliary colicky pain. Five cases were presented with obstructive jaundice and five with acute cholecystitis. Right upper quadrant mass was palpable in three patients. All patients underwent cholecystectomy. Open surgery was planned and performed in three patients. Laparoscopic cholecystectomy was planned in nine patients but converted to open surgery in three cases. Nine patients had an uneventful postoperative course. One patient developed wound infection and one patient a postoperative pulmonary infection. One patient developed acute abdomen in the 2nd postoperative day and was re-operated for bile peritonitis. No mortality was seen in the series.  相似文献   
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The aim of this study was to demonstrate an assessment of left internal mammary artery (LIMA) patency and anatomy by standard left ventriculography, and to define a proposal for predicting LIMA function according to left ventriculography outcome. A total of 335 patients with an indication of coronary angiography were included. Standard coronary angiography and left ventriculography were performed initially. Visualization of LIMA occurred in the late phase of ventriculography and the LIMA visualization frame rate was counted for each patient. Then selective LIMA angiography was performed and LIMA diameter, LIMA course and anatomy, and subclavian artery anatomy were noted. Finally, the results of left ventriculography and LIMA angiography were compared by statistical analysis. During left ventriculography, LIMA was visualized in 96.4% of the patients. The mean LIMA visualization frame rate was 53.8 ± 17.7 and the mean LIMA diameter was 2.60 ± 0.36 mm. There was a strong correlation between LIMA visualization frame rate and LIMA diameter, LIMA course, and also asymptomatic subclavian artery disease (P < 0.001). Regression analysis showed that LIMA visualization frame rate is the major independent determinant for LIMA diameter prediction (P < 0.001); LIMA diameter, LIMA course, proximal LIMA side branch, and subclavian artery disease are the major predictors of LIMA visualization on left ventriculography (P < 0.001). LIMA patency and anatomy can be evaluated accurately with a simple method using left ventriculography. Besides direct visualization of LIMA, the visualization frame rate may constitute a reliable parameter for assessing LIMA function. A LIMA visualization frame rate of less than 50 is associated with a healthy and well-sized LIMA.  相似文献   
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Hearing loss has commonly been reported in association with thyroid disorders and during treatment with propylthiouracil. The relationship between hyperthyroidism and the auditory system has not been previously investigated. The aim of this cross-sectional, case-control study was to investigate hearing loss in patients with Graves' disease (GD). The study population consisted of patients with newly diagnosed GD and healthy controls. Pure tone audiometry at frequencies of 250, 500, 1000, 2000, 4000 and 8000 Hz, along with immittance measures including tympanometry and acoustic reflex tests, were performed in all participants. Twenty-two GD patients and 22 healthy controls consented to inclusion in the study. The differences between groups with regards to age and gender distribution were statistically insignificant (P = 0.567 and P = 0.757, respectively). The hearing thresholds of right and left ears were also similar in both groups (P > 0.05). When single-ear evaluations were taken into account (total of 44 ears for both groups), hearing thresholds in the GD group were significantly higher than healthy controls at all frequencies (P < 0.05). Following testing at the designated frequencies, the only significant effect of thyrotoxicosis was observed with frequencies of 4000 and 8000 Hz. The odds ratio for having hearing loss at a frequency of 8000 HZ associated with GD was 14.97 (95% confidence interval 4.03-55.64). In patients with GD, right and left pure tone audiometric findings at a frequency of 8000 Hz correlated positively with FT3, FT4 and negatively with TSH. Our results are highly suggestive of a decrease in hearing ability in patients with GD, particularly at high frequencies. Further studies are needed to help elucidate the mechanisms behind hearing loss which develops in association with GD.  相似文献   
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Fertilization problems are the major problems that may be faced in 30–55% of the patients during an intracytoplasmic sperm injection (ICSI) cycle. A successful oocyte activation depends on factors related to both sperm and oocyte, and one of the important factors that mediates the process is Ca2+ concentration within the oocyte. Artificial oocyte activation (AOA) is a method used for fertilization problems that commonly involve the usage of Ca2+ ionophores and is usually used in problems such as total fertilization failure (TFF) and globozoospermia. The aim of the present study was to investigate possible effects of AOA for different groups of patients with fertilization failure. Four groups of patients (previous TFF, low oocyte number, severe sperm quality, and frozen sperm (FS) group) that underwent ICSI with AOA were included in the study. All groups had similar control groups with same indications except TFF, where AOA was not performed. Fertilization rates were significantly higher in the TFF group than those observed in other AOA groups. Fertilization rates and quality of embryos observed in the remaining AOA groups were higher than those of the controls, which were statistically insignificant. Prgenancy rates were higher in all AOA groups compared to the controls, although the differences were significant in FS group only. Quality of embryos and pregnancy rates were lower in the TFF group compared to the remaining AOA groups indicating possible concomitant problems. Fertilization rates, quality of embryos and pregnancy rates seemed to be increased in all indication groups suggesting that not only TFF patients but also a wide variety of patients with different indications may benefit from AOA.

Abbreviations: ICSI: Intracytoplasmic sperm injection; ARTs: Assisted reproductive techniques; Ca: Calcium; AOA: Artificial oocyte activation; TFF: Total fertilization failures; OAT: Oligoasthenoteratozoospemia; IVF: In vitro fertilization; SOAT: Severe OAT; LON: Low ooctye number; FS: Frozen sperm; hCG: human chorionic gonadotrophin; PVP: polyvinylpyrrolidone; HSA: human serum albumin  相似文献   

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