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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
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Yetgin S Aslan D Unal S Tavil B Kuşkonmaz B Elmas SA Olcay L Cetinkaya DU 《Pediatric hematology and oncology》2008,25(6):492-501
Peripheral blood smears of 43 patients (26 males, median age 18 months, range: 6-180 months) with nutritional iron-deficiency anemia (IDA) were examined for the presence of trilineage hematological dysplasia. Twelve patients were reexamined for dysplastic findings after achieving a normal Hb and hematocrit level for age by the end of 2-3 months of iron treatment. A control group of 17 age-matched healthy children were also included. Neutrophils with loss of membrane entirety and protrusions were remarkable in 34/43 (79%) in the IDA group versus 1/12 (8%) after iron treatment and none of the control group. Microspherocytes were seen in 9/43 (21%) of IDA patients. Additionally, trilienage dysplasia was observed in the bone marrow samples available in 3 of the patients. It has been shown that iron-deficiency results in cellular DNA and RNA alterations, cell-cycle G1/S phase arrest, and apoptosis. Rac GTPases have been shown to control actin cytoskeleton, influencing cell polarity, microtubule dynamics, and the cytoskeletal organization of hematopoietic cells. Thus, the findings described above in neutrophils and red cells suggest a plausible link between iron and the Rac GTPase gene family. It may be a new avenue for iron waiting for proof. 相似文献
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Riza Madazli Mehmet Aytac Yuksel Mahmut Oncul Metehan Imamoglu Handan Yilmaz 《Archives of gynecology and obstetrics》2014,289(1):49-53
Purpose
To determine maternal and fetal outcomes in pregnancies with Systemic Lupus Erythematosus (SLE), and to evaluate the prognostic factors that may affect obstetrical outcomes.Methods
Sixty-five consecutive cases of SLE and pregnancy were included in this retrospective clinical study, performed in a university hospital which is also a reference center for SLE. Lupus pregnancies followed and delivered during the period from 2002 to 2011 in our department are evaluated. Obstetric outcomes and prognostic factors were main outcome measures.Results
The mean patient age was 28.8 years and the nulliparity rate was 43.1 %. Disease flare-up occurred in 7.7 % of patients. Lupus anticoagulants, anticardiolipin IgG and IgM antibodies were positive in 27.6, 15.3 and 13.8 % of patients, respectively. Mean gestational age at delivery was 36.6 ± 4.2 and mean birth weight was 2,706 ± 927 g. Stillbirth, fetal growth restriction, preeclampsia and preterm delivery rates were 4.6, 18.5, 9.2 and 27.6 %, respectively. Cases with uterine artery Doppler abnormalities had significantly poorer obstetric outcomes.Conclusions
Multidisciplinary approach to the care of pregnant women with SLE is mandatory for good maternal and fetal outcomes. Uterine artery Doppler seems to be a good prognostic factor for adverse obstetric outcomes. 相似文献108.
Huriye A. Parlakgumus Cantekin Iskender Pinar Caglar Aytac Ebru Tarim 《Archives of gynecology and obstetrics》2012,286(5):1147-1151
Purpose
To investigate if normotensive and hypertensive patients with intrauterine growth restricted (IUGR) fetuses were different with respect to maternal and fetal characteristics and Doppler flow.Methods
The records of patients with IUGR fetuses who had to be delivered before 34th gestational week because of fetal distress were examined. Early Doppler abnormalities were defined as increased umbilical artery resistance and redistribution of blood flow in the middle cerebral artery while late Doppler abnormalities were defined as the absence or reversal of umbilical artery blood flow and Doppler flow changes in venous Doppler. t Test, Chi-square test and Mann–Whitney U test were used for the comparison of data as appropriate. p?<?0.05 was considered statistically significant.Results
Thirty-six patients were hypertensive while 42 were normotensive. Gestational week at admission for hypertensive and normotensive groups (30.8?±?3.6 vs. 32.3?±?3.1) (p?=?0.057), time to delivery (7.1?±?12.6 vs. 4.3?±?9.1?days) (p?=?0.267) and gestational week at delivery (31.8?±?3.1 vs. 32.9?±?2.9) (p?=?0.117) were similar. Birth weight was significantly lower (1242?±?534 vs. 1516?±?504?g) (p?=?0.02) in the normotensive group. The frequency of having oligohydramnios (64.2?% for normotensive and 44.4?% for hypertensive patients) (p?=?0.079) was similar in both groups. Early Doppler abnormalities were more common in hypertensive group (75 vs. 40.5?%) (p?=?0.001) while late Doppler abnormalities were more common in normotensive group (25 vs. 59.5?%) (p?=?0.001).Conclusion
Birth weight was lower and late Doppler abnormalities were more common in the normotensive group while early Doppler abnormalities were more common in hypertensive group. 相似文献109.
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Kursat Bora Carman Engin Tutkun Hinc Yilmaz Cengiz Dilber Tahir Dalkiran Baris Cakir Didem Arslantas Yildirim Cesaretli Selin Aktaş Aykanat 《European journal of pediatrics》2013,172(6):821-827
Elemental mercury exposure occurs frequently and is potentially a toxic, particularly in children. Children are often attracted to elemental mercury because of its color, density, and tendency to form beads. Clinical manifestations of elemental mercury intoxication vary depending on its form, concentration, route of ingestion, and the duration of exposure. We present data on 179 pediatric cases of elemental mercury poisoning from exposure to mercury in schools in two different provinces of Turkey. Of all patients, 160 children had both touched/played with the mercury and inhaled its vapors, while 26 children had only inhaled the mercury vapor, two children reported having tasted the mercury. The median duration of exposure was 5 min (min 1–max 100), and 11 (6 %) children were exposed to the mercury for more than 24 h at home. More than half of the children (51.9 %) were asymptomatic at admission. Headache was the most common presenting complaint. The results of physical and neurological examinations were normal in 80 (44.6 %) children. Mid-dilated/dilated pupils were the most common neurological abnormality, and this sign was present in 90 (50.2 %) children. Mercury levels were measured in 24-h urine samples daily, and it was shown that the median urinary level of mercury was 29.80 μg/L (min, 2.40 μg/L; max, 4,687 μg/L). A positive correlation was also found between the duration of exposure and urinary mercury levels (r?=?0.23, p?=?0.001). All patients were followed up for 6 months. On the first follow-up visit performed 1 month after discharge, the neurological examinations of all patients were normal except for those patients with peripheral neuropathy and visual field defects. On the last follow-up visit at the sixth month, only two children still experienced visual field defects. In conclusion, this study is one of the largest case series of mercury intoxication of students in schools. Elemental mercury exposure can be potentially toxic, and its symptomatology is variable, particularly in children. Therefore, school staff and children should be aware of the risk of mercury toxicity. Pediatricians also need to warn parents and children about the hazards of playing with any chemical. 相似文献