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81.
The aim of this study was to investigate the microleakage in class V cavities restored with four conventionally setting glass ionomers (CGIs) and one resin-modified glass ionomer (RMGI) following erbium:yttrium–aluminium–garnet (Er:YAG) laser or conventional preparation. Four hundred class V cavities were assigned to four groups: A and B were prepared by an Er:YAG laser; C and D were conventionally prepared. In groups B and D, the surface was additionally conditioned with Ketac conditioner. Each group was divided into five subgroups according to the glass ionomer cement (GIC) used: groups 1 (Ketac Fil), 2 (Ketac Molar), 3 (Ionofil Molar), 4 (Ionofil Molar Quick) and 5 (Photac Fil Quick). After thermocycling, a 2% methylene blue solution was used as dye. Scanning electron microscope (SEM) photographs were taken to show the conditioner’s effect. Complete marginal sealing could not be reached. PhotacFil showed less microleakage than the conventionally setting glass ionomer cements (CGICs) investigated. Conditioning laser-prepared cavities did not negatively influence microleakage results except for Ionofil Molar Quick.  相似文献   
82.
Individual differences in adolescent exercise behavior are to a large extent explained by shared environmental factors. The aim of this study was to explore to what extent this shared environment represents effects of cultural transmission of parents to their offspring, generation specific environmental effects or assortative mating. Survey data on leisure-time exercise behavior were available from 3,525 adolescent twins and their siblings (13–18 years) and 3,138 parents from 1,736 families registered at the Netherlands Twin Registry. Data were also available from 5,471 adult twins, their siblings and spouses similar in age to the parents. Exercise participation (No/Yes, using a cut-off criterion of 4 metabolic equivalents and 60 min weekly) was based on questions on type, frequency and duration of exercise. A model to analyze dichotomous data from twins, siblings and parents including differences in variance decomposition across sex and generation was developed. Data from adult twins and their spouses were used to investigate the causes of assortative mating (correlation between spouses = 0.41, due to phenotypic assortment). The heritability of exercise in the adult generation was estimated at 42%. The shared environment for exercise behavior in adolescents mainly represents generation specific shared environmental influences that seem somewhat more important in explaining familial clustering in girls than in boys (52 versus 41%). A small effect of vertical cultural transmission was found for boys only (3%). The remaining familial clustering for exercise behavior was explained by additive genetic factors (42% in boys and 36% in girls). Future studies on adolescent exercise behavior should focus on identification of the generation specific environmental factors.  相似文献   
83.
The aim of this study was to determine whether it is safe to use photo-activated disinfection (PAD) during root canal treatment without heating the periodontal tissues. Root canals of 30 freshly extracted single-rooted teeth were prepared using ProFiles up to size ISO 40 and then filled with photo-sensitiser: tolonium blue (1.2 mg/l). The 635 nm diode laser was used with the manufacturer’s endo-tip. Samples were irradiated for 150 s (output power 100 mW, approximate energy density 106.16 J/cm2). Temperatures were recorded at working length on the external root surface. After 150 s of PAD irradiation, the average temperature rise was 0.16 ± 0.08°C. All values were lower than the 7°C safety level for periodontal injury. It was concluded that, regarding the temperature increase, the use of PAD in root canals could be considered harmless for periodontal tissues.  相似文献   
84.
Array CGH was used to identify recurrent copy number alterations (RCNA) characteristic of either BRCA1-related or sporadic ovarian cancer. After preprocessing, both groups of patients were modeled using a recurrent Hidden Markov Model to detect RCNA. RCNA with a probability higher than 80% were called. After removing RCNA present in both groups, the genes present in the remaining RCNA were investigated for enrichment of pathways from external databases. More RCNA were observed in the BRCA1 group, and they display more losses than gains compared to the sporadic group. When focusing on the type of RCNA, no significant difference in length was seen for the gains, but there was a statistically significant difference for the losses. In the sporadic group, a great proportion of the altered regions contain genes known to have a function in cell adhesion and complement activation, whereas the BRCA1 samples are characterized by alterations in the HOX genes, metalloproteinases, tumor suppressor genes, and the estrogen-signaling pathways. We conclude that BRCA1 ovarian tumors present a different type, number, and length of RCNA; a huge amount of the genome is lost, resulting in important genomic instability. Moreover, important biological pathways are altered differentially when compared to the sporadic group. Hum Mutat 30:1–10, 2009. © 2009 Wiley-Liss, Inc.  相似文献   
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Mirtazapine is indicated for major depression and used for anxiety in adults; however, little is known about its application in pediatric populations. This is an 8-week open-label pilot study of mirtazapine in children with social phobia age 8-17 years. Primary outcomes were symptom improvement based on clinician rating and self-report, as well as tolerability based on rates of discontinuation due to adverse effects. Fifty-six percent (10/18) responded to treatment, 17% (3/18) achieved full remission. Social phobia symptoms improved significantly during the first 2 weeks of treatment, as did comorbid symptoms of depression and anxiety. Eleven patients (61%) did not complete all 8 weeks of treatment; four patients (22%) discontinued due to adverse effects including fatigue and irritability. The others discontinued due to study burden (28%), insufficient response (6%), or to pursue herbal treatment (6%). Significant weight gain was observed. Larger controlled trials are needed to further evaluate efficacy and safety.  相似文献   
88.
First year after head and neck cancer: quality of life.   总被引:3,自引:0,他引:3  
PURPOSE: Treatment regimens for head and neck cancer patients profoundly affect several quality-of-life domains. Rehabilitative needs have been identified through cross-sectional analyses; however, few studies have prospectively assessed quality of life, included assessment of psychosocial variables, and identified predictors of long-term follow-up. PARTICIPANTS AND METHODS: The present study addresses these limitations through a prospective assessment of 105 patients with a newly diagnosed first primary squamous cell carcinoma of the oral cavity, pharynx, or larynx. Participants were enrolled onto a larger randomized controlled trial comparing a provider-delivered smoking cessation intervention with a usual-care-advice control condition. Participants completed a battery of self-report measures after diagnosis and before treatment and additional quality-of-life instruments at 1 and 12 months after initial smoking cessation advice. RESULTS: Participants displayed improvements at 12 months in functional status (P = .006) and in the areas of eating, diet, and speech; however, the latter three represent areas of continued dysfunction, and the changes were not statistically significant. Despite these improvements, patients reported a decline in certain quality-of-life domains, including marital (P = .002) and sexual functioning (P = .017), as well as an increase in alcohol use (P < .001). Predictors of quality of life at 12 months included treatment type, the Vigor subscale of the Profile of Mood States instrument, and quality-of-life scores obtained 1 month after initial smoking cessation advice. CONCLUSION: Results reinforce the need for rehabilitation management through the integration of psychologic and behavioral interventions in medical follow-up.  相似文献   
89.
The purpose of this study was to examine the effectiveness of the hinged ankle-foot orthosis (HAFO), posterior leaf spring (PLS), and solid ankle-foot orthosis (SAFO), in preventing contracture, improving efficiency of gait, and enhancing performance of functional motor skills in 30 children (21 male, 9 female; mean age 9 years 4 months; age range 4 to 18 years,) with spastic hemiplegia. Following a 3-month baseline period of no ankle-foot orthosis (AFO) use, each AFO was worn for 3 months after which ankle range of motion, gait analysis, energy consumption, and functional motor skills were assessed. The HAFO and PLS increased passive ankle dorsiflexion and normalization of ankle rocker function during gait. Normalization of knee motion in stance was dependent upon the knee abnormality present and AFO configuration. The HAFO was the most effective in controlling knee hyperextension in stance, while PLS was the most effective in promoting knee extension in children with >10 degree knee flexion in stance. Energy efficiency was improved in 21 of the children, with 13 of these children demonstrating the greatest improvement in HAFO and PLS. Improvements in functional mobility were greatest in the HAFO and PLS.  相似文献   
90.
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