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991.
992.
Aim: To determine the factors affecting the topographic characteristics of the optic nerve head in a normal Turkish population. Methods: A cross‐sectional study was performed on the optic nerve head of the right eyes of 613 healthy subjects of both sexes aged 11?77 years using a confocal scanning laser ophthalmoscope. The study population was divided into three groups (<20 years, 20?50 years, and>50 years) to evaluate age‐related changes in the optic nerve head topography. A total of 15 variables were determined. Statistical analysis was performed using Student's t‐test, anova, Tukey HSD test, linear regression analysis and Pearson's correlation coefficient. Results: Four eyes were excluded from the study due to poor image quality. There were 307 female subjects and 302 male subjects. The mean age of the subjects was 42.1 ± 15.1 years. The mean optic disc areas were 1.99 ± 0.45 mm2 and 1.97 ± 0.41 mm2 for male and female subjects, respectively. The disc area of the subjects ranged between 1.01 and 4.19 mm2. Disc area was found to be associated with all of the optic nerve head variables studied, and was also found to be significantly increased with advancing age (P < 0.05). The only variable that showed a sex‐related difference was neuroretinal rim volume, which was found to be higher in female subjects in all cases. Conclusion: Optic disc area was found to be the main determinant of the optic nerve head topography in a normal population. Optic disc area was found to be significantly increased with ageing in a normal population. These acquired changes to the optic disc could suggest stretching of the scleral ring, which may highlight the role of advancing age on the pathogenesis of glaucomatous optic neuropathy.  相似文献   
993.
We recently reported that progesterone treatment attenuated some of the subjective effects of smoked cocaine in female cocaine users. In this study, we further examined the interaction between progesterone and cocaine in both male and female cocaine users using subjective, physiological and behavioral outcomes. A total of 10 subjects, 6 male and 4 female cocaine users, had two experimental sessions. Before each session, participants received either two oral doses of 200 mg of progesterone or placebo. Two hours after the second dose of medication treatment, the participants received a 0.3 mg/kg dose of cocaine intravenously and started the self-administration period, in which five optional doses of cocaine were available. Progesterone treatment attenuated the cocaine-induced diastolic blood pressure increases without affecting the systolic blood pressure and heart rate increases. Progesterone treatment also attenuated the subjective ratings of high and feel the effect of last dose in response to cocaine but did not affect cocaine self-administration behavior. These results suggest that progesterone attenuates some of the physiological and subjective effects of cocaine in both male and female participants. The effects of progesterone treatment on cocaine dependence need to be further studied in controlled trials.  相似文献   
994.
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Electrical injury can cause a variety of cardiac arrhythmias. Atrial fibrillation as a result of such injury is fairly rare, however, and is rarer still in cases of low-tension electrical injury. We present the case of a patient who developed acute atrial fibrillation in association with low-voltage electrical injury, which resolved after the intravenous administration of digoxin.  相似文献   
998.
BACKGROUND AND AIM: The aim of the present study was to compare the therapeutic efficacy of three different regimens in childhood chronic hepatitis B (CHB) infection. METHODS: A total of 182 children with CHB infection were prospectively allocated to three random groups. Sixty-two patients in the first group received high-dose interferon (IFN)-alpha 2b (10 MU/m2) thrice/weekly alone for 6 months. In the second (n = 60) and third groups (n = 60), IFN-alpha was used for 6 months (5 MU/m2) thrice/weekly in combination with lamivudine (LAM) (4 mg/kg, maximum 100 mg/day) for 12 months. Lamivudine was started simultaneously with IFN in the second group, while it was started 2 months prior to IFN injections in the third group. RESULTS: The initial mean alanine aminotransferase (ALT) values for the first, second and third groups were 109 +/- 93 IU/L, 101 +/- 64 IU/L and 92 +/- 42 IU/L, respectively (P > 0.05). At the end of the therapy, ALT values decreased to 82 +/- 111 IU/L, 38 +/- 41 IU/L and 29 +/- 16 IU/L in groups 1, 2 and 3, respectively. The mean ALT value of the first group was significantly different to the second and third groups (P = 0.046 and P = 0.002, respectively) at the end of the therapy and these differences were found to be sustained after 18 months. However, results in the second and third groups were similar (P > 0.05). There were no significant differences in HBeAg clearance and anti-HBe seroconversion at the initial stage, 12 months and 18 months between the three groups (P > 0.05). Hepatitis B virus (HBV) DNA clearance in the first group was different from the second and third groups, while the second and third groups had similar HBV DNA clearance ratios at 12 and 18 months. No significant difference was found in the complete response (normalization of ALT, clearance of HBV DNA and seroconversion of anti HBe) ratios of all groups (at 12 months: 28.8, 45.5, 35.8% and at 18 months 33.3, 49 and 34% in groups 1, 2 and 3, respectively, P > 0.05). CONCLUSIONS: Although the ALT normalization and HBV DNA clearance ratios of IFN plus LAM combination groups were better than the high-dose IFN-alpha monotherapy group, no significant difference was found in the complete response ratios of all three groups.  相似文献   
999.
BACKGROUND: There is one published case-control study of nail disorders in hemodialysis patients. The nail changes that occur in renal transplant recipients have not been investigated specifically. OBJECTIVE: The aim of this study was to determine prevalence rates of nail disorders in hemodialysis patients and renal transplant recipients, and to investigate whether these nail pathologies are related to hemodialysis and renal transplantation. METHODS: One hundred and eighty-two hemodialysis patients and 205 renal transplant recipients were screened for the presence of nail disorders. The findings in these groups were compared with findings in 143 healthy individuals. RESULTS: One hundred and twenty-seven patients (69.8%) in the hemodialysis group and 116 patients (56.6%) in the renal transplant recipients had at least one type of nail pathology. Absence of lunula, splinter hemorrhage, and half-and-half nails were significantly more common in the hemodialysis patients than in the renal transplant recipients. Leukonychia was significantly more frequent in the renal transplant recipients than in the hemodialysis patients and controls. CONCLUSION: Hemodialysis patients and renal transplant recipients have higher rates of nail disease than the healthy population. Renal transplantation may reduce the frequencies of splinter hemorrhage and half-and-half nails. Interestingly, leukonychia increases significantly after renal transplantation.  相似文献   
1000.
The fulminating form of subacute sclerosing panencephalitis is an extremely rare condition. Imaging findings are usually not correlated with clinical staging. We describe a 4-year-old girl with severe neuronal loss, demyelination, and gliosis in subcortical white matter by magnetic resonance spectroscopic examination even though she was diagnosed as clinical stage II. In 2 months' time, her clinical status worsened significantly. Follow-up magnetic resonance spectroscopy revealed findings that were consistent with clinical status. It is our opinion that magnetic resonance spectroscopy could demonstrate a rapidly progressive fulminating course of subacute sclerosing panencephalitis even in the early clinical stages.  相似文献   
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