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The aim was to investigate clinical characteristics of young children with a hair pulling problem. Parents/caregivers of young children (0–10 years old) with a hair pulling problem (N = 110) completed an online survey. The majority reported that their child experienced mild to moderate impairment/distress due to hair pulling, and overall clinical characteristics were similar to adult samples, although some differences were noted (e.g., less awareness of pulling). We also compared preschool-aged and school-aged children within the sample. Symptom severity, pleasure during pulling and gender ratio remained stable across the age groups. The preschool-aged children demonstrated less impairment/distress, comorbidity, and treatment seeking; pulled from fewer body areas; and were less likely to be aware of the act or experience tension prior to pulling. In conclusion, clinical characteristics of childhood hair pulling are largely similar to adult/adolescent hair pulling problems, but there are some notable differences, particularly among pre-school aged children.  相似文献   
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Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time.  相似文献   
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OBJECTIVE:: Pulse pressure (PP) is a risk marker for cardiovascular disease (CVD) in individuals 50 years and older. Inflammation is suggested to influence atherosclerosis, but could also increase PP. We aimed to examine the combined effects of PP and the inflammatory marker sialic acid, and their independent roles on CVD risk. METHODS:: From a population-based study in Sweden between 1962 and 1965, 18?429 men and 19?414 women at the age of 50 or older were selected and followed for first CVD event until 2005. We investigated the biological interactions between sialic acid and PP. The associations of PP and sialic acid with risk of CVD were calculated by using Cox proportional hazards model. Adjustments were made for conventional risk factors, mean arterial pressure (MAP) and socioeconomic status. RESULTS:: The mean age was 59.5 (SD 6.5) years and the number of incident CVD events in men and women were 3641 and 3227, respectively. No biological interaction was seen between PP and sialic acid. In men, the adjusted hazard ratio for PP was 0.92 [95% confidence interval (CI) 0.88-0.96, P?相似文献   
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