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Increased expression of GLI1, the main Hedgehog signalling pathway effector, is related to unfavourable prognosis and progressive disease of certain breast cancer subtypes. We used conditional transgenic mice induced to overexpress GLI1 in the mammary epithelium either alone or in combination with deletion of one Trp53 allele to address the role of elevated GLI1 expression in breast tumour initiation and progression. Induced GLI1 expression facilitates mammary gland tumour formation and this was further increased upon heterozygous deletion of Trp53. The GLI1-induced primary tumours were of different murine molecular subtypes, including Normal-likeEx, Class8Ex, Claudin-LowEx and Erbb2-likeEx. The gene expression profiles of some of the tumours correlated well with the PAM50 subtypes for human breast cancer. Whole-exome sequencing revealed somatic mutation profiles with only little overlap between the primary tumours. Orthotopically serially transplanted GLI1-induced tumours maintained the main morphological characteristics of the primary tumours for ≥10 generations. Independent of Trp53 status and molecular subtype, the serially transplanted GLI1-induced tumours were able to grow both in the absence of transgenic GLI1 expression and in the presence of the GLI1 inhibitor GANT61. These data suggest that elevated GLI1 expression has a determinant role in tumour initiation; however, additional genetic events are required for tumour progression.  相似文献   
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The reported skew distribution of caries prevalence in preschool children, with a small group of children with very high caries prevalence, stresses the importance of early identification for prevention.The present study aimed to describe the caries prevalence in a group of Swedish preschool children and to identify caries risk factors in this population. 221 children, 2 to 3 years old, agreed to participate in the study (82%). A standardized questionnaire was used to describe socio-economic factors, dietary and oral hygiene habits and exposure to fluoride. Initial and manifest dental caries was diagnosed and the presence of plaque was visually observed without disclosing solution. Saliva and plaque samples were collected for identification of mutans streptococci (MS). For statistical analysis,the Student's t-test,the Chi-square test and Fisher's exact test were used. The caries prevalence among the 2 to 3 year-olds was 7 and 18 percent respectively. An association between early childhood caries and a number of factors was found e.g. the presence of MS and visible plaque, nocturnal meals, frequent sugar consumption, mothers' state of employment and immigrant background. The Public Dental Health Service has been successful in decreasing the number of children with caries, but the challenge remains to be able to control caries in the high-risk group. The skew distribution, with many children without caries and a smaller group with very high caries prevalence, was confirmed.The study provided insight into various factors, useful for monitoring children at risk of developing early childhood caries.  相似文献   
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Patients considering undergoing combined orthodontic-orthognathic treatment for correction of malocclusion require appropriate information, particularly with respect to duration of treatment. The primary aim of this study was to determine the duration of orthodontic treatment carried out in conjunction with orthognathic surgery and to analyze the influence of selected explanatory variables. A further aim was to compare the duration of orthodontic treatment in patients treated by orthodontists at Link?ping University hospital orthodontic clinic and six regional orthodontic clinics. This is a retrospective study, based on data from the orthodontic records of patients who had undergone orthognathic surgery at the University Hospital Maxillofacial Unit in Link?ping, Sweden, from 2000 to 2005. The subjects comprised 207 out of 233 patients (107 women and 100 men), aged 15.8-56.9 years, median 24.2 years at the time of surgery: 26 patients were excluded, either diagnosed with a syndrome, or because it was impossible to follow up the entire treatment. 59 subjects had undergone orthodontic treatment at the University hospital orthodontic clinic and 148 at the 6 regional orthodontic clinics. The variables recorded were gender, malocclusion, the number of appointments (scheduled and emergency) and treatment setting. The median value for pre-operative orthodontic treatment time was 19.2 months (range 2.4-68.4); for postoperative orthodontic treatment 4.6 months (range 0-18.8) and for total orthodontic treatment 27.8 months (range 5.9-79.1). For the University hospital orthodontic clinic, pre-operative (16.7 months) and total orthodontic treatment times (25 months) were significantly shorter than for the regional clinics; the duration of postoperative treatment was significantly longer (4.1 months). No other explanatory variables had a significant influence on the duration of orthodontic treatment. Compared with the regional orthodontic clinics, there were significantly fewer scheduled appointments at the University hospital orthodontic clinic, but no significant difference in emergency attendance.  相似文献   
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Myotonic dystrophy or dystrophia myotonica (DM) is a hereditary neuromuscular multisystem disease with a varying clinical expressivity and severity. The objective of this study was to assess the oral health in children with myotonic dystrophy and to compare it with a control group. Fifty-six DM patients, aged 2.7-18.0 yr, were compared with age- and gender-matched control patients with respect to caries, plaque, and gingivitis. Oral function and signs of temporomandibular dysfunction (TMD) were assessed, and the ability to co-operate in dental treatment was estimated. Questionnaires concerning eating habits, dental care, traumatic injuries to teeth, and orofacial function were also used. The DM patients had significantly more caries, plaque, and gingivitis than did control patients. They had more TMD problems and lower co-operation ability than the healthy control persons. General sedation was frequently needed to carry through dental treatment. DM patients are at risk of caries, gingivitis and TMD problems, and need intensified prophylactic care. Behavior management problems are common.  相似文献   
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Purpose: The aim of this study was to validate the conceptual definitions of accessibility and usability, and to explore differences between objective accessibility assessments and subjective ratings of usability in different client groups.

Method: The Housing Enabler and the Usability in My Home instruments were used for 131 persons above 18 years of age, living in ordinary housing and receiving a housing adaptation grant. Covariation between accessibility in four different housing sections and three different usability aspects were explored, for the total sample and for six sub-samples reflecting person-environment-activity transactions or demographic factors.

Results: Significant correlations were found in the total sample, among clients aged 75 - 84, women, clients living alone, as well as among clients with high dependence in personal and instrumental ADL and in outdoor activities. Subjective usability evaluations of activity aspects and physical environmental aspects were correlated to accessibility indoors and outdoors, while personal and social aspects of usability were correlated to outdoor accessibility.

Conclusions: Accessibility and usability are concluded to be different but related concepts. The results indicate that e.g. age, civil status and ADL dependence affect how clients assess aspects of their housing situation. For efficient planning and evaluation of housing adaptations, assessment of housing accessibility, usability, and dependence in ADL is recommended.  相似文献   
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