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排序方式: 共有2217条查询结果,搜索用时 15 毫秒
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Won Hee Lim Bo Liu Du Cheng Daniel J Hunter Zhendong Zhong Daniel M Ramos Bart O Williams Paul T Sharpe Claire Bardet Su‐jung Mah Jill A Helms 《Journal of bone and mineral research》2014,29(4):892-901
Odontoblasts, cementoblasts, ameloblasts, and osteoblasts all form mineralized tissues in the craniofacial complex, and all these cell types exhibit active Wnt signaling during postnatal life. We set out to understand the functions of this Wnt signaling, by evaluating the phenotypes of mice in which the essential Wnt chaperone protein, Wntless was eliminated. The deletion of Wls was restricted to cells expressing Osteocalcin (OCN), which in addition to osteoblasts includes odontoblasts, cementoblasts, and ameloblasts. Dentin, cementum, enamel, and bone all formed in OCN‐Cre;Wlsfl/fl mice but their homeostasis was dramatically affected. The most notable feature was a significant increase in dentin volume and density. We attribute this gain in dentin volume to a Wnt‐mediated misregulation of Runx2. Normally, Wnt signaling stimulates Runx2, which in turn inhibits dentin sialoprotein (DSP); this inhibition must be relieved for odontoblasts to differentiate. In OCN‐Cre;Wlsfl/fl mice, Wnt pathway activation is reduced and Runx2 levels decline. The Runx2‐mediated repression of DSP is relieved and odontoblast differentiation is accordingly enhanced. This study demonstrates the importance of Wnt signaling in the homeostasis of mineralized tissues of the craniofacial complex. © 2014 American Society for Bone and Mineral Research. 相似文献
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Daniela N Schulz Eline S Smit Nicola E Stanczyk Stef PJ Kremers Hein de Vries Silvia MAA Evers 《Journal of medical Internet research》2014,16(3)
Background
Different studies have reported the effectiveness of Web-based computer-tailored lifestyle interventions, but economic evaluations of these interventions are scarce.Objective
The objective was to assess the cost-effectiveness and cost-utility of a sequential and a simultaneous Web-based computer-tailored lifestyle intervention for adults compared to a control group.Methods
The economic evaluation, conducted from a societal perspective, was part of a 2-year randomized controlled trial including 3 study groups. All groups received personalized health risk appraisals based on the guidelines for physical activity, fruit intake, vegetable intake, alcohol consumption, and smoking. Additionally, respondents in the sequential condition received personal advice about one lifestyle behavior in the first year and a second behavior in the second year; respondents in the simultaneous condition received personal advice about all unhealthy behaviors in both years. During a period of 24 months, health care use, medication use, absenteeism from work, and quality of life (EQ-5D-3L) were assessed every 3 months using Web-based questionnaires. Demographics were assessed at baseline, and lifestyle behaviors were assessed at both baseline and after 24 months. Cost-effectiveness and cost-utility analyses were performed based on the outcome measures lifestyle factor (the number of guidelines respondents adhered to) and quality of life, respectively. We accounted for uncertainty by using bootstrapping techniques and sensitivity analyses.Results
A total of 1733 respondents were included in the analyses. From a willingness to pay of €4594 per additional guideline met, the sequential intervention (n=552) was likely to be the most cost-effective, whereas from a willingness to pay of €10,850, the simultaneous intervention (n=517) was likely to be most cost-effective. The control condition (n=664) appeared to be preferred with regard to quality of life.Conclusions
Both the sequential and the simultaneous lifestyle interventions were likely to be cost-effective when it concerned the lifestyle factor, whereas the control condition was when it concerned quality of life. However, there is no accepted cutoff point for the willingness to pay per gain in lifestyle behaviors, making it impossible to draw firm conclusions. Further economic evaluations of lifestyle interventions are needed.Trial Registration
Dutch Trial Register NTR2168; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2168 (Archived by WebCite at http://www.webcitation.org/6MbUqttYB). 相似文献94.
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Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine. 相似文献
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Callahan EJ Bertakis KD Azari R Robbins JA Helms LJ Chang DW 《Journal of the American Geriatrics Society》2000,48(1):30-35
OBJECTIVES: To explore resident physician-patient interaction in primary care to address issues relevant to quality of care for older people. DESIGN: A sample of 509 new, adult, nonpregnant patients was assigned to the care of second- and third-year residents in primary care clinics. Care was compared for three subgroups of patients: older patients (65 years or older; n = 45), those aged 18 to 44 years (n = 320), and those aged 45 to 64 years (n = 144). SETTING: Observations were made at the family medicine and general internal medicine clinics at the University of California, Davis. MEASUREMENTS: Self-report by means of the Medical Outcomes Study Short Form-36 (MOS SF-36) was used to determine patient demographics and patient health status. Two measures of satisfaction were obtained gauging reaction to medical care in general and to the videotaped visit specifically. Videotapes were coded for content using the Davis Observation Code. RESULTS: Self-reported health status of older persons was poorer than that of younger groups as measured by the MOS SF-36. Differences in demographics were explored and then controlled, along with physical health status in subsequent analyses. Supporting prior studies, this study found that older patients had more return visits and reported higher levels of satisfaction than did younger comparison groups. Contrary to prior literature, older patients were found to have longer visits than did younger cohorts. The physician-patient interaction was significantly different in many areas between these three groups. Whereas older patients experienced more chatting in their visits, they were given less counseling, asked fewer questions, had less discussion about their families and their use of substances, were asked to change their health behavior habits less often, and were given less health education. For older patients, more of each visit was spent checking on compliance with earlier treatment and developing treatment plans. CONCLUSIONS: These results provide a new and more detailed view of how resident physician-patient interaction differs between older and younger groups and raise important issues on whether quality of care needs for this population are being adequately addressed, particularly regarding mental health issues. 相似文献
100.
Two combined oxygen and carbon dioxide electrodes were assessed in neonates, infants, and children up to 16 years. They were convenient to use and the measurement error for PtcCO2 was acceptable. In both models, however, the PtcO2 electrode had a reduced performance compared with a single electrode. 相似文献