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51.
To study the self-consciousness of children with learning disabilities (LD) and to identify related factors. Methods Five hundred and sixty pupils graded from 1 to 6 in an elementary school were investigated. According to the pupil rating scale revised screening for learning disabilities (PRS), combined Raven‘s test (CRT) and achievement of main courses, 35 of 560 pupils were diagnosed as LD children. Thirty-five children were selected from the average children and 35 from advanced children in academic achievement equally matched in class, gender, and age with LD children as control groups. The three groups were tested by Piers-Harris children‘s self-concept scale. Basic information of each subject was collected by self-made questionnaire. Results Compared with the average and advanced children, LD children got significantly lower scores in self-concept scale. Based on logistic regression analysis, 3 factors were identified, including family income per month, single child and delivery model. Conclusion The results suggest that self-consciousness of children with LD is lower than that of normal children.  相似文献   
52.
Offshore oil exploration creates threats to coastal ecosystems, including increasing urbanization and associated effluent releases. Genotoxicity biomarkers in mussels were determined across a gradient of coastal zone influences of offshore petroleum exploration in southeastern Brazil. Coastal ecosystems such as estuaries, beaches and islands were seasonally monitored for genotoxicity evaluation using the brown mussel Perna perna. The greatest DNA damage (5.2%?±?1.9% tail DNA and 1.5‰? ±?0.8‰ MN) were observed in urban estuaries, while Santana Archipelago showed levels of genotoxicity near zero and is considered a reference site. Mussels from urban and pristine beaches showed intermediate damage levels, but were also influenced by urbanization. Thus, mussel genotoxicity biomarkers greatly indicated the proposed oil exploration and urbanization scenarios that consequently are genetically affecting coastal organisms.  相似文献   
53.
目的:研究羟基磷灰石人工骨(HAB)/异体脱矿骨粉(DBP)复合物修复骨缺损的效果,以期获得一种既具有传导性又具有骨诱导性的复合材料。方法:将HAB/DBP复合物、HAB、异体脱矿骨(DMB)植入兔桡骨中段骨缺损处,设置空白对照,在2、4、8、12周分别取材,观察新骨形成及骨缺损修复情况。结果:HAB/DBP组、DMB组2周时可见骨断端附近有大量软骨细胞聚集,并有少量基质形成。4周时,大量软骨细胞及少量骨小架。8周时,见大量骨小梁和层板状骨形成。12周见层板成熟骨组织和哈佛系统形成。其成骨能力及新骨生成量明显高于HAB组及空白组。结论:HAB/DBP复合物为一种既具有骨传导性又具有骨诱导性的骨缺损修复材料,具有与DMB同样的诱导骨生成的能力,可能成为一种具有临床应用前景的骨缺损及修复材料。  相似文献   
54.
We tested the null hypothesis that there is no difference in the sealing ability of GuttaFlow, RoekoSeal, and AH26 in root canals. Sixty extracted mandibular premolars were filled with AH26 (lateral compaction), RoekoSeal, or GuttaFlow (modified single-cone). The sealing ability of the root canal fillings was measured weekly (4 weeks) by using a glucose penetration model. Kruskal-Wallis test revealed significant differences in glucose penetration between the experimental groups at weeks 1, 2, 3, and 4. Whereas GuttaFlow showed the highest amount of leakage at all times, AH26 showed the lowest. There was no significant difference between RoekoSeal-filled and AH26-filled root canals throughout the experimental period. AH26 showed better sealing ability in root canals than GuttaFlow.  相似文献   
55.
目的探讨Simodont虚拟仿真系统中虚拟涡轮机机头的辅助光照对实际操作的影响,为口腔临床技能训练提供指导。 方法选取四川大学华西口腔医学院口腔医学专业本科生56人为研究对象,按随机数表法随机分为两组,实验组(虚拟仿真牙科训练机的涡轮机头的辅助灯处于打开状态)和对照组(虚拟仿真牙科训练机的涡轮机头的辅助灯处于关闭状态)的学生分别使用Simodont虚拟仿真系统在不同辅助光照情况下进行练习和考核,并在临床冷光灯条件下使用玻璃板模拟临床操作,采用t检验对比分析两组的得分。并通过问卷调查了解学生的使用体验。 结果不同辅助光照条件下,Simodont虚拟训练机操作总分(t = 1.342,P = 0.181)和临床冷光灯条件下玻璃板的操作结果(t = -0.585,P = 0.561)差异均无统计学意义;但Simodont总分构成项中"Leeway sides(洞缘偏差)"项有光组学生分数为5.38 ± 4.69,大于无光组分数(4.32 ± 2.92),差异有统计学意义(t = 2.252,P = 0.025)。 结论尚不能认为Simodont系统在有辅助灯的条件下可以影响医学生的培训效果,但在有辅助照明的情况下操作可能更容易误碰到规定区域边界的侧方。问卷结果显示,Simodont虚拟仿真系统是一种值得推广的教学模式。  相似文献   
56.
目的:探讨人唾液对正常及肿瘤细胞在体外粘附有无不同影响。方法:接种NIH—3T3及MEC-1细胞在预先涂有或未涂唾液的24孔培养板上,用细胞计数法分别在接种后2、4、6和8h计数贴壁细胞。结果:NIH-3T3细胞及MEC-1细胞在涂有唾液的塑料底物上在2、4、6、和8h其贴壁抑制率分别为35%、41%、26%、34%和10%、9%、8%、4%。结论:人全唾液能抑制体外培养的NIH-3T3细胞的粘附,但对MEC-1细胞的影响不大。  相似文献   
57.
58.

Introduction

This study examined the identity of the microbiome of deep dentinal caries and its correlation with the inflammation status of caries-induced pulpitis.

Methods

Seventy-five cases were diagnosed based on the American Association of Endodontics's diagnostic criteria and divided into 4 groups: normal pulp with deep caries (NP; n = 13), reversible pulpitis with only cold-evoked pain (CRP; n = 17), reversible pulpitis with both cold/heat-evoked pain (CHRP; n = 24), and symptomatic irreversible pulpitis (SIP; n = 21). Samples were sequenced by 16S rDNA. Alpha and beta diversity were determined. Linear discriminant analysis effect size (LEfSe) analysis was used to detect intergroup differences, and receiver operating characteristic (ROC) curves were generated to assess the role of the caries microbiome in caries-induced pulpitis.

Results

The 16S rDNA sequencing yielded 9100 operational taxonomic units. Lactobacillus had the highest relative abundance at the genus level among the 4 groups. There were significant differences in the distribution of the microbiome among the groups. In an alpha diversity analysis, species richness differed between the CRP group and the other groups. In a beta diversity analysis, the distribution of microorganisms in the SIP group was significantly different from those in the other 3 groups. LEfSe analysis indicated substantial differences in the microbiome among the groups, and the areas under the ROC curves (AUC) were all high (AUC: 0.734–0.952).

Conclusions

Characterization of the caries microbiome has the potential to become an auxiliary method for the diagnosis of pulpitis. This finding may prompt new research on diagnostic strategies for caries-induced pulpitis.  相似文献   
59.
60.
The purpose of this article is to review the literature on interprofessional education (IPE) and report on a preliminary survey of the current status of interprofessional education in seven academic health centers (AHCs) that have schools of dentistry associated with them. There is wide variability in interpretation of the term "interprofessional," and many barriers to interprofessional education exist including already overcrowded curricula in health professions schools, lack of support from faculty and administration, and financial constraints. Based on interviews completed at the authors' home institutions, it was recommended that topics such as ethics, communication skills, evidence-based practice, and informatics could be effectively taught in an interprofessional manner. Currently, some academic health centers are attempting to develop interprofessional education programs, but most of these efforts do not include dental students. Of the seven AHCs investigated in this study, only two had formal interprofessional educational activities that involved students from two or more health professions education programs. Dental school participants in this study professed a strong interest in interprofessional programs, but many interviewees from other professional schools and AHC administrators perceived that the dental school was isolated from other schools and disinterested in IPE. Many health care setting models in the future will include dentists as part of an interdisciplinary health care team; consequently, it is important for dental schools to become an active participant in future interprofessional educational initiatives.  相似文献   
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