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Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system. Nearly 85% of MS patients are recognized with relapsing-remitting MS (RRMS), a typical clinical course of disease which is distinguished by several episodes of relapses, separated by remissions of neurological impairment. Failure of repair mechanisms is a main factor in progression of neurological dysfunction in MS. Several lines of evidence suggest that Reelin (RELN) signaling pathway can contribute in the regulation of repair mechanisms in MS patients. In the present study, we assessed expression levels of RELN and Disabled-1 (DAB1), two key genes in RELN signaling pathway, in peripheral blood of 50 RRMS patients and 50 matched healthy subjects. RELN was significantly down-regulated in total MS patients, and total female patients compared with the matched controls. However, no statistically significant difference was found in DAB1 mRNA expression between MS patients and controls. Furthermore, considerable correlations were detected between expression levels of RELN and DAB1 in the patients group. There were no significant correlations between expression levels of genes and EDSS, disease duration or age at onset. Our study provides evidences for the role of RELN signaling pathway in the pathogenesis of MS. Further studies are required to clarify the exact clinical significance of this pathway in MS patients.  相似文献   
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ObjectivesTo explore whether there were any differences in orthodontic treatment need, treatment complexity, treatment time, or the number of visits between a group of children receiving early intervention (extraction of upper and lower deciduous canines) and an age- and condition-matched control group without intervention.Materials and MethodsPatient records and study casts in the late mixed or early permanent dentitions of 46 subjects (20 from the extraction group and 26 from the control group) of an earlier prospective longitudinal study were retrieved. Orthodontic treatment need and complexity were assessed by the index of complexity, outcome, and need (ICON). Statistical calculations were performed by t-test for parametric outcome variables (treatment time, number of visits, and orthodontic treatment need) and Fisher exact test for the categorical variable (tooth extractions).ResultsThere were no statistically significant differences between the groups in ICON scores of orthodontic treatment need (extraction group, mean score 59.8; control group, mean score 52.8), number of visits (mean of about 15 visits for both groups), or treatment time (extraction group, mean 21.5 months; control group, mean 20.3 months). The extraction of permanent teeth was more prevalent in the deciduous canine extraction group (59%) as compared with the control group (28%); however, this was not statistically significant (P = .07) but showed a tendency toward worsening the crowding and the future need of orthodontic extractions.ConclusionsEarly removal of deciduous primary canines will reduce neither the need for later orthodontic treatment nor its complexity, nor will it shorten the treatment time.  相似文献   
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Visceral leishmaniasis is one of the most important parasitic diseases that is endemic in some parts of Iran. This study aimed to determine current distribution of visceral leishmaniasis in four distinct geographical zones of Iran. A cross-sectional study was conducted using direct agglutination test (DAT) on 9396 and 2559 serum samples collected from humans and domestic dogs, respectively during the period of 2007 through 2009. Altogether, 403 (4.3%) out of 9396 human serum samples collected from 4 distinct geographical locations showed anti-Leishmania antibodies with titers ≥ 1:3200. Physical examinations performed on 142 sero-positive cases with anti-Leishmania antibodies at titers of 1: 3200 to 1:102400 among whom fever (94.4%), paleness (67.6%) and hepato-splenomegaly (42.2%) were the predominant clinical signs and symptoms. The highest sero-prevalence rate (1.55%) was found in children ≤ 5 years old. Out of 2559 serum samples collected from domestic dogs, 212 (8.3%) were DAT positive (≥ 1:320). Leishmania infantum is the principal causative agent of the disease was isolated from both infected humans and dogs in Iran. Our findings indicate that Mediterranean visceral leishmaniasis with different distribution occurs in different geographical locations of Iran.  相似文献   
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ObjectivesTo assess and compare the three-dimensional treatment changes in palatal surface area and volume using either tooth-borne (TB) or tooth bone–borne (TBB) rapid maxillary expanders and to evaluate the long-term effects of the two devices and the incidence of the relapse between the groups.Materials and MethodsA total of 52 consecutive patients who met the eligibility criteria were recruited and allocated to either the TB group, mean age 9.3 years (standard deviation [SD], 1.3), or the TBB group, mean age 9.5 years (SD, 1.2). Study casts were taken before, directly after, 1 year after, and 5 years after expansion. Study casts were digitized, superimposed, and evaluated. Participants were randomly allocated in blocks of different sizes using the concealed allocation principle in a 1:1 ratio.ResultsChanges in palatal volume, palatal surface area, and palatal projection area within and between the groups up to 5 years after expansion followed the same pattern and did not show any statistically significant differences between the groups. Relapse was seen in 15% of the patients. It seemed that open-bite and a Class III growth pattern could be assumed as prognosis-deteriorating factors in regard to stability of the treatment.ConclusionsThere were no significant differences between the TB and TBB groups in palatal volume, palatal shell area, or palatal projection area directly after expansion or at 1 year and 5 years after expansion, which implies that the two devices gave rise to the same immediate and long-term outcomes.  相似文献   
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