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Although immunologic processes and hereditary factors are suggested to play an important role in alopecia areata, the specific etiology is unclear. Iron deficiency has been suggested to play a role, but its effect is controversial. In our case control study, we found a higher mean level of serum iron and ferritin and a lower mean level of TIBC in patients compared to control subjects, but the differences did not reach significance.  相似文献   
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AIM: To determine the accuracy of tomography in the linear measurement of alveolar bone at maxillary sinus/nose location. METHODS: Two dry skulls each marked with 10 pairs of guttaperchas placed on buccal and lingual sides of the maxillary ridge were used in this in vitro study. The distance between the alveolar crest and the sinus/nasal floor was measured on tomographic views, prepared by linear and spiral techniques. The ridges were then sectioned so that each section would include one pair of buccal and lingual guttaperchas. The actual distances directly measured on the sections were compared to those of the equivalent tomographic sections (the magnification co-efficient was applied). Paired t-test was used to statistically analyze the data. RESULTS: The measurement error with the application of linear tomography and spiral tomography was shown to be 0.455 ± 0.838 mm (P = 0.029) and 0.17 ± 0.78 mm (P = 0.347), respectively. There was a statistically significant difference between the liner tomography values and actual values (P = 0.029). This difference was representative of underestimation. McNamara’s test was used to assess the ± 1 mm error; 73.7% of the linear values and 84.2% of the spiral values were within the ± 1 mm error limit. McNamara’s test did not show any significant differences between the 2 methods in this regard (P = 0.625). The linear values were significantly different to the actual values (P = 0.029) but not to the spiral values (P = 0.185). CONCLUSION: Spiral tomography has enough accuracy for the measurement of alveolar ridge height. Although linear tomography somewhat underestimates the actual values it provides satisfactory accuracy.  相似文献   
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Imaging characteristics of dry age-related macular degeneration   总被引:1,自引:0,他引:1  
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Objective  Poisoning does the most serious damages in pediatrics. In the northeast of Iran (Golestan province), opium is used widely for symptomatic therapy of routine illnesses in young children by parents. In the present study, opium toxicity was assessed in young children referred to pediatric centers in our area. Methods  This survey was done as a prospective cross-sectional study. At first, a pilot study was undertaken to estimate the condition of opium intoxicated children and evaluate the validity of questionnaire. We collected data in collaboration with committee of Adverse Drug Reactions (ADR) in Golestan Province. All members of ADR committee in pediatric centers were trained to complete questionnaires in referred or admitted children under-5-year. Data was entered into computer and analyzed by Chi-square and Fisher exact test. Results  In this survey, 67 opium-intoxicated children were recruited. Minimum age of the cases was 6 days and maximum 5-year. Uneducated mothers, in most cases, gave opium to the child. Most of them were from the low socio-economic level. Ethnic was disparity was observed. Four deaths occurred. Conclusion  As the results showed, opioids are dangerous in pediatric population, especially under 5-year. Respiratory depression, bradypnea, coma and death are the serious outcomes of opium toxicity in pediatrics. Such a practice of unrestricted use of opium contributes to children mortality and so it is essential to launch educational programs.  相似文献   
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Background: The human leukocyte antigen (HLA) matching between organ donor and recipient is an acceptable strategy in clinical transplantation since 1964. However, in bone marrow transplantation, finding matched donors is often problematic. Thus new method for down regulation of HLA can be an alternative strategy to solve this problem. Objective: To examine the effect of serum starvation on HLA class I expression in human peripheral blood mononuclear cells (PBMCs). Methods: PBMCs were cultured in RPMI-1640 supplemented with 10% FBS (non-starved cells) as well as in medium only (starved cells) for 16, 24, 48, 72, 96h under standard cell culture conditions. The pattern of cell death and HLA class I expression was determined by flowcytometry. Antigenicity of the starved PBMCs was evaluated in a one-way mixed lymphocyte culture by MTT assay. Results: Mean fluorescence intensity (MFI) of different indicated starved PBMCs gradually decreased and this reduction was stable after 96h of re-feeding with medium containing FBS. Under serum starvation condition, PBMCs showed apoptotic cell death pattern. There was a linear correlation between percentages of cells, which exhibited the late apoptosis death pattern and serum starvation period (r=0.88, p<0.01). Surprisingly, the starved PBMCs lost their stimulatory property in mixed culture with allo-reactive lymphocyte. Conclusions: Membrane HLA class I expression could be stably reduced in 96h starved human PBMCs culture condition, decreasing their allo-reactivity while their viability rate is enough for possible clinical application.  相似文献   
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