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This study examines three potential contributions (i.e., additive only, hierarchical compensatory, and hierarchical conditional) of mentor support to youth academic adjustment, taking into account interactions with support from mothers and teachers. We derived data from a larger study of the Big Brothers Big Sisters (BBBS) of Canada community mentoring program. The sample included 427 youth (average age 9.8 years; 64% girls, 56% White) who received one-to-one community-based mentoring for at least three months. We assessed perceptions of support from mothers and teachers before the match and assessed perceptions of support from mentors five times throughout the mentoring experience. Hierarchical linear regression analyses showed that mentor support predicted positive changes in youth academic adjustment (i.e., school attitude, academic self-efficacy, assistance seeking, and problem solving) mainly when mentees already reported high support from their mother. This finding clearly supports the conditional model and invites researchers to question the assumption that mentoring constitutes a corrective experience for young people (i.e., the compensatory model). BBBS agencies are strongly encouraged to involve parents in the mentoring process and to view them as experts, assets, and allies in their effort to meet the youth’s needs.  相似文献   
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Langerhans cells (LC) are dendritic cells of the immune system able to capture intraepithelial pathogens and migrate to regional lymph nodes to present them to naive T cells. Up to now immunohistological studies on human gingival LC have been carried out using antibodies against HLA-DR or CD1a molecules. A new marker of LC called Langerin (CD207) and described, among other subcellular localisations, in the Birbeck granules is now available in immunohistochemistry. The purpose of this in situ study was to quantify and to compare Langerin+ versus CD1a+ LC number in order to show differences in the expression of these molecules, if any, and to determine which marker is the most specific. The present study was conducted using nine frozen healthy gingival samples. Double immunofluorescence procedures were performed with an anti-Langerin antibody revealed by FITC and with an anti-CD1a-PE antibody. Mounted slides were analysed by fluorescence microscopy and quantifications were performed on projected slides associated with a grid of 0.015 mm(2). Our results have shown that 1/ the number of CD1a+ LC was significantly increased (P=0.01) when compared with Langerin+ LC 2/ 92% of Langerin+ LC co-expressed CD1a 3/ only 82% of CD1a+ cells co-expressed Langerin 4/ a positive correlation was noted between CD1a+ and Langerin+ LC numbers. The present study has revealed the heterogeneity in the phenotype of gingival LC population and shown that Langerin seems the most specific marker for the study of LC.  相似文献   
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In a prospective, double blind, and randomized study, we compared methylprednisolone and ketoprofen after anesthesia for multiple third molar extraction. In addition to paracetamol, 90 patients were allocated to receive intravenously either ketoprofen 100 mg or methylprednisolone 1 mg/kg. Severity of pain was measured with visual analogue scale (VAS) in recovery room. Sixty-three percent of patients receiving methylprednisolone had a VAS score <30 mm compared with 42% of those receiving ketoprofen (P = 0.04), with no difference in the consumption of morphine. We observed only marginal difference between methylprednisolone and ketoprofen to relieve pain after this surgery.  相似文献   
26.

Background  

We describe the risk indicators for oral mucositis (OM) in paediatric oncology patients hospitalised in the Institut Gustave Roussy (Villejuif-Paris) and treated with alkylant chemotherapy with autologous peripheral blood progenitor cells.  相似文献   
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Malignant melanoma of the lacrimal sac is rare, and only 21 cases have been reported in the world literature. They have an insidious onset and may look like chronic dacryocystitis. In only 6 of these cases were there no recurrences. In most of the survivors, the diagnosis was made early which appears to be the most important prognostic factor. Hence a CT-scan in cases of persistent dacryocystitis is important. Melanoma of the lacrimal duct system is a good example of a condition requiring a multidisciplinary approach between ophthalmologist and maxillofacial surgeon. Any persistently symptomatic lacrimal duct system may need a maxillofacial consultation.  相似文献   
28.
AIM: Kabuki make-up Syndrome is so named because of the characteristic facies of the affected patient. The face is similar to a Kabuki actor's mask. The main aim of this report was to describe the oral features in Kabuki Syndrome, focusing on the tooth anomalies. PATIENTS AND METHODS: Five subjects with Kabuki Syndrome, identified by the Child Neuropsychiatric Clinic of the University of Sassari, Italy, were enrolled. Their medical records were reviewed and oral and dental examinations were completed. The diagnosis was based upon the typical pattern of malformations and dysmorphic features reviewed by Matsumoto and Niikawa. RESULTS: All patients showed typical characteristics of the Syndrome such as a long palpebral fissure, lower palpebral eversion, arched eyebrows, short nasal septum, prominent and large ears, fingertip pads, mental retardation, and paramedian elevation of the lower lip. CONCLUSION: Kabuki make-up Syndrome is of unknown origin but a genetic aetiopathogenesis has been proposed. It is extremely rare; in Japan, where it is most frequent, it affects 1:32000 newborns. The typical facies of the syndrome, combined with general medical and dental examinations, are very important for diagnosis confirmation.  相似文献   
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PURPOSE: The purpose of this in vivo study of primary teeth was to analyze the ultrastructure and microbiology of dentin layers affected by caries lesions before and after restorations with resin-modified glass ionomer. METHODS: Samples of carious dentin from primary teeth removed prior to restoration placement (baseline-0 day) were compared with samples taken after 30 and 60 days. Dentin from 8 primary molars was analyzed by scanning electron microscopy (SEM) and dentin from 22 primary molars was examined microbiologically to compare bacteria (total of viable counts, Streptococcus spp, Streptococcus mutans, Lactobacillus spp, and Actinomyces spp) before and after treatment (30 and 60 days). RESULTS: Baseline caries samples had enlarged dentinal tubules with bacteriol invasion. SEM samples after treatment suggest better tissue organization, with more compact collagen fibers arrangement and narrower dentinal tubules. The number of bacteria decreased in all samples at both 30 (98%) and 60 (96%) days, with all bacteria species showing similar trends. CONCLUSIONS: The minimal intervention approach is very effective to promote beneficial changes in the lesion environment and favorable conditions for the healing process in primary teeth.  相似文献   
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