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111.

Purpose

The current study aimed to explore the characteristics of psychological adjustment among Chinese left-behind children (LBC) in rural areas, and to examine the association between separation duration from parent/parents (SDP) and children’s psychological adjustment and the extent to which personality mediates this hypothesized link.

Methods

We surveyed 534 rural children and adolescents aged 10–17 years at school (440 LBC and 94 non-LBC) in 2013, who were selected for participation using stratified cluster sampling from two counties in Chongqing, China. Measures used included socio-demographic variables, age at the commencement and end of the separation from parents, the revised Chinese Juvenile Eysenck Personality Questionnaire, and the Adolescent Psychological Adaptability Scale.

Results

Most children (82.4%) had experienced separation from parents. t test results showed a marginally significant difference (p?=?.08) in psychological adjustment between LBC (mean?=?64.44, SD?=?8.62) and non-LBC (mean?=?66.16, SD?=?9.26). LBC’s mean SDP was 5.64 years (SD?=?3.90). Correlation analysis showed that children’s SDP was negatively associated with psychological adjustment. Structural equation modeling showed that neuroticism, but not extraversion or psychoticism, fully mediated the link between children’s SDP and psychological adjustment.

Conclusion

Personality (neuroticism) is one of the mediating pathways through which long-term SDP may predict poor psychological adjustment among children. Given the detrimental impact of long-term SDP, interventions should target the mediating pathway to buffer against the negative impact of parental separation on the affected rural children and to improve their mental health.
  相似文献   
112.
Previously published results from studies of the in vivo effects of fluoride on cyclic AMP are contradictory. Because of the important physiological role of cyclic AMP as a "second messenger" in numerous metabolic processes, it was important to clarify the effect of fluoride on cyclic AMP. This study was designed to monitor cyclic AMP levels in the plasma, liver and kidney of rats at intervals of 0.5, 4 and 24 hours following acute intraperitoneal or intubated treatment with a single dose of 15 mg fluoride/kg and to relate cyclic AMP levels to plasma and tissue fluoride concentrations determined at the same time.  相似文献   
113.
This study evaluated the results of three methods of managing simulated unilateral dislocated fractured mandibular condyles in the rabbit. The first method consisted of surgical reduction of the fractured condyle to its anatomic position and its subsequent fixation with a titanium plate. The second method differed from the first by completely detaching the condyle, then replacing it as free graft. The third method left the fractured condyle in its dislocated position outside the glenoid fossa. Eighteen rabbits were used, 6 animals for each method. Half the animals in each group were killed at 4 weeks, the other half at 14 weeks postoperatively. Clinical, morphologic, functional, radiologic, and histologic examinations were conducted on all animals. The results indicated that open reduction with internal fixation with no disruption of the blood supply to the condyle provided the most favorable results. While closed reduction without internal fixation gave good functional results, definite reduction in ramus height on the operated site was observed in this group of animals. Animals that had open reduction and internal fixation using the condyle as a free graft did not do as well as the other two groups. Despite good mouth opening and occlusion, more animals showed facial asymmetry and it was more severe. None of the condyles were lost as result of necrosis, but healing took longer when compared with the other group of animals.  相似文献   
114.
牙周基础治疗后龈沟液中IL-6和TNF-α的变化   总被引:1,自引:0,他引:1  
目的 :探讨牙周基础治疗对龈沟液中IL - 6和TNF -α水平的影响。方法 :选取成人牙周炎位点 87个 ,用夹心ELISA法进行龈沟液IL - 6和TNF -α水平的检测并记录相关临床指标 ,然后行牙周基础治疗。治疗后 6周再次检测观察牙的龈沟液IL - 6和TNF -α水平及相关临床指标 ,比较牙周基础治疗前后龈沟液中IL - 6、TNF -α及相关临床指标的差异。结果 :牙周基础治疗前后探诊深度 (PD)、附着丧失 (AL)及龈沟液中IL - 6、TNF -α水平都有显著性改变 (P <0 .0 5 ) ;龈沟液量、菌斑指数 (PLI)和改良龈沟出血指数 (mBI)有非常显著性改善 (P <0 .0 1)。结论 :牙周基础治疗在降低各项临床指标的同时对龈沟液中IL - 6和TNF -α水平也有明显影响 ,确实有控制牙龈炎症的作用  相似文献   
115.
Sporadic cases have been reported of ectopic thymic tissue formed along the path of embryologic descent from the mandibular region to the mediastinum, usually manifesting as an asymptomatic mass. Here is reported the case of an 8-month-old boy with a tender palpable mass in the right upper lateral neck. Preoperative posteroanterior chest radiograph revealed normal structures in the mediastinum superior including the thymus. Magnetic resonance imaging showed a 4-cm x 4-cm soft-tissue mass in the left submandibular region. Surgical resection was performed and histopathologic examination showed that the mass was composed of thymic lymphoid tissue and epithelial cells. Immunohistochemical features included positive expression of LCA, CKpan, EMA, CD20 and CD43 antibodies. The clinical 14-month follow up was negative and the child was growing normally after operation. Ectopic thymus in the submandibular region is uncommon; surgical treatment is the definitive means of pathological diagnosis. Prior to surgery, the presence of a mediastinal thymus should be confirmed to prevent the risk of a total thymectomy.  相似文献   
116.
舌大小与开He相关性的研究   总被引:6,自引:0,他引:6  
目的 研究舌大小与开He之间的关系。方法 采用B型超声成像方法分别测量正常He与开He患者的舌大小,通过牙He与正常He舌大小的比较,研究舌大小与开He的相关性。结果 开He患者的舌大小测量结果均值大于正常He者,而且这种差别有显著的统计学意义。结论 与正常He者比较,开He患者存在舌过大的特性。  相似文献   
117.
DF暂封糊剂的研制   总被引:2,自引:1,他引:2  
目的:研制一种单组份、糊剂型、水硬性暂封材料。方法:通过测定材料在水中的凝固速度及凝固后材料表面性状,对水硬性材料成份的种类、赋形剂的种类及凝固促进剂的种类进行筛选。结果:水硬性材料A2的凝固速度最快,赋形剂B2的效果最好,凝固促进剂C1的作用优于C2。结论:采用A2、B2、C1作为暂封材料基本组成效果最佳,凝固24h后抗压强度达13.94MPa±2.07MPa。  相似文献   
118.
激光焊接间距对牙科铸造纯钛性能影响的实验研究   总被引:2,自引:0,他引:2  
目的:研究激光焊接铸造纯钛时不同的焊接间距对纯钛性能的影响。方法:将铸造钛试样按照焊接间距的大小分为4组:0.00、0.25、0.50、1.00mm组,肉眼、扫描电镜观察焊缝区外观,测试焊件的抗拉强度,整铸件为对照组。结果:各试验组焊缝区显示全层焊透、无明显气孔等焊接缺陷,断口电镜显示为延展性(韧窝)与脆性(气孔、裂纹)共存的形貌。各实验组与对照组间抗拉强度方差分析结果显示差异无显著性(P>0.05)。结论:不同的焊接间距对铸钛的机械性能无明显影响。  相似文献   
119.
An otherwise-healthy 2-year-old Japanese female presented with a polyp-like lesion on the palatal surface at the incisive papilla. The appearance of the lesion was similar to that of a congenital epulis. The histological findings showed proliferating mesenchymal components that contained mainly smooth muscle admixed with collagen fibres, nerve fibres, small vessels and mucous salivary glands. The immunohistochemical staining findings for α-smooth-muscle actin, desmin and S-100 protein were all positive. The histological diagnosis was therefore leiomyomatous hamartoma, based on clinical microscopic observations.  相似文献   
120.
头颈部肿瘤的基因治疗研究进展   总被引:2,自引:0,他引:2  
郭伟 《上海口腔医学》1998,7(2):121-122
基因治疗恶性肿瘤已从实验室走向临床试用阶段。目前国际上已批准的基因治疗方案130余项,其中70%的方案是肿瘤基因治疗。头颈部肿瘤相对表浅、直观,且有区域淋巴结转移的特性,这为基因治疗的应用提供了天然的条件。近年文献报道由腺病毒介导的自杀基因治疗动物肿瘤模型的实验研究,为临床基因治疗头颈癌展示良好的应用前景。虽然人们已克隆出多种可用于肿瘤基因治疗的基因,但尚未找到一种临床应用后抗肿瘤效果非常显著的治疗性目的基因。这将有待于通过相关的研究,以期实现人类基因组研究计划发现和鉴定  相似文献   
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