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11.
Retinitis pigmentosa (RP) is the most common manifestation of inherited retinal diseases with high degree of genetic, allelic, and phenotypic heterogeneity. CEP250 encodes the C‐Nap1 protein and has been associated with various retinal phenotypes. Here, we report the identification of a mutation (c.562C>T, p.R188*) in the CEP250 in a consanguineous family with nonsyndromic RP. To gain insights into the molecular pathomechanism underlying CEP250 defects and the functional relevance of CEP250 variants in humans, we conducted a functional characterization of CEP250 variant using a novel Cep250 knockin mouse line. Remarkably, the disruption of Cep250 resulted in severe impairment of retinal function and significant retinal morphological alterations. The homozygous knockin mice showed significantly reduced retinal thickness and ERG responses. This study not only broadens the spectrum of phenotypes associated with CEP250 mutations, but also, for the first time, elucidates the function of CEP250 in photoreceptors using a newly established animal model.  相似文献   
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Background

Several methods have been developed to determine a person’s physical activity level. However, there is limited evidence in determining whether someone is physically active or not. This study aims to determine the level of physical activity and to compare the usage of short version International Physical Activity Questionnaire (IPAQ-SF) and pedometer among overweight and obese women who were involved in the My Body is Fit and Fabulous at home (MyBFF@home) study.

Methods

Baseline and sixth month data from the MyBFF@home study were used for this purpose. A total of 169 of overweight and obese respondents answered the IPAQ-SF and were asked to use a pedometer for 7 days. Data from IPAQ-SF were categorised as inactive and active while data from pedometer were categorised as insufficiently active and sufficiently active by standard classification. Data on sociodemographic and anthropometry were also obtained. Cohen’s kappa was applied to measure the agreement of IPAQ-SF and pedometer in determining the physical activity level. Pre-post cross tabulation table was created to evaluate the changes in physical activity over 6 months.

Results

From 169 available respondents, 167 (98.8%) completed the IPAQ-SF and 107 (63.3%) utilised the pedometer. A total of 102 (61.1%) respondents were categorised as active from the IPAQ-SF. Meanwhile, only 9 (8.4%) respondents were categorised as sufficiently active via pedometer. Cohen’s κ found there was a poor agreement between the two methods, κ?=?0.055, p?>?0.05. After sixth months, there was +?9.4% increment in respondents who were active when assessed by IPAQ-SF but ??1.3% reductions for respondents being sufficiently active when assessed by pedometer. McNemar’s test determined that there was no significant difference in the proportion of inactive and active respondents by IPAQ-SF or sufficiently active and insufficiently active by pedometer from the baseline and sixth month of intervention.

Conclusion

The IPAQ-SF and pedometer were both able to measure physical activity. However, poor agreement between these two methods were observed among overweight and obese women.
  相似文献   
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AIM: To develop a three-dimensional culture model of human dental pulp cells (DPCs) with biodegradable porous calcium polyphosphate (CPP) scaffolds. METHODOLOGY: Human DPCs were isolated from three donors. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate the cytotoxicity of CPP compared with hydroxyapatite (HA) and beta-tricalcium phosphate (beta-TCP). Values were analysed using unpaired t-tests. Cells were seeded onto porous CPP scaffolds with pore sizes in the range of 200-300 microm. The nature of cellular adaptation in the three-dimensional culture model was then evaluated visually by scanning electronic microscopy (SEM) and confocal laser scanning microscopy (CLSM). The apoptotic property of cells on the scaffolds was also assessed by DNA staining with CLSM. RESULTS: The cytotoxicity assay indicated that there was no significant difference between CPP and HA for each donor's original cells (P>0.05). Calcium polyphosphate had no cytotoxic effect on DPCs, whilst SEMs showed that cells successfully adhered to CPP scaffolds and spread amongst pores. On the cell surface, fine processes and matrix secretory granules were found. Confocal laser scanning microscopy showed that cells took on a three-dimensional structure with signs of vitality. CONCLUSION: Porous CPP scaffolds are promising for the establishment of a three-dimensional culture model of DPCs.  相似文献   
16.
PURPOSE: This laboratory study compared visual-tactile examination with conventional radiographs, digital radiographs, and laser fluorescence in the detection of occlusal occult caries on extracted premolar teeth. METHODS: Extracted premolars without obvious caries or restorations were collected from school dental clinics. Occlusal surfaces of 320 extracted premolars were examined visually with an explorer, then examined using the KaVo Diagnodent unit and scored using specific criteria. The teeth were exposed using conventional and digital radiography, respectively. The radiographs were assessed for dentin radiolucencies beneath the occlusal surface. RESULTS: Of the 320 teeth used in this study, 302 were scored as sound by visual-tactile examination. Of these, 57 (19%) demonstrated dentin radiolucency on conventional bite-wings, and 245 (81%) were scored as radiographically sound. Thus, the sensitivity and specificity values of the visual-tactile examination compared with conventional radiography were 81% and 44%, respectively. In contrast, Diagnodent produced results of 82% sensitivity and 36% specificity when compared with conventional radiography. When compared to digital radiography, the sensitivity and specificity values of the visual-tactile examination were 90% and 44%, respectively. In contrast, when compared to digital radiography, Diagnodent showed a very low specificity of only 32%, although sensitivity was still high at 91%. Differences in specificity among the techniques were statistically significant (P < .03), whereas differences in sensitivity were not (P > .01). CONCLUSIONS: Although the diagnosis of occult dentinal caries may be further enhanced by the Diagnodent, a combination of visual-tactile examination and either conventional or digital radiography should identify over 80% of lesions.  相似文献   
17.
目的:分析比较成型后的基托塑料可能发生的变色。方法:对不同粉、液比例灌注成型的基托塑料和常规模压成型的基托塑料,用分光测色仪观察颜色稳定性。结果:粉、液以2∶1体积比灌注成型的义齿基托,表面平整光滑,色调、饱和度与常规模压成型的义齿基托相同,而其表面可抛光性优于常规法。结论:2种方法成型的义齿基托对紫外线的敏感性无显著性差异。  相似文献   
18.
粉浆涂塑铝瓷冠的匹配性研究   总被引:2,自引:0,他引:2  
粉浆涂塑铝瓷冠核冠与面瓷间良好的匹配性是保证铝瓷冠修复成功的重要前提。作者采用扫描电镜,X射线能谱仪观察和热休克试验三种方法,观察了两种粉浆涂塑铝瓷冠(In-Ceram和GI-I)的匹配性,结果表明,In-Ceram的热休克抗力的158℃,GI-热休克抗力为172℃,两种铝瓷冠面瓷与铝瓷核冠间界面均结合紧密,界面两侧有元素扩散现象。提示In-Ceran和GI-I型粉浆涂塑铝瓷冠的匹配性均良好。  相似文献   
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20.
两种牙面干燥法对窝沟封闭剂脱落率的影响   总被引:3,自引:0,他引:3  
比较了使用压缩空气与使用洗耳球热空气干燥牙面对封闭剂脱落率的影响。结果表明:压缩空气干燥牙面较洗耳球热空气干燥牙面,封闭剂完全脱落率低;上颌磨牙远中腭沟、近中沟,差异有高度显著性(P<0.01),下颌磨牙面差异无显著性(P<0.05)。说明使用压缩空气干燥牙面有利于封闭剂的保留,特别对于不易操作的上颌磨牙影响更加明显,而对于能直视、易操作的下颌磨牙,使用洗耳球热空气干燥牙面也能达到较好的效果  相似文献   
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