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排序方式: 共有2068条查询结果,搜索用时 15 毫秒
91.
Humam Saltaji Michael P. Major Mostafa Altalibi Mohamed Youssef Carlos Flores-Mir 《The Angle orthodontist》2012,82(6):1115
Objective:To systematically review the long-term skeletal stability after maxillary advancement with distraction osteogenesis (DO) in cleft lip and palate (CLP) patients.Materials and Methods:Electronic databases, grey literature, and reference list searches were conducted. The inclusion criteria were stability of maxillary advancement with distraction osteogenesis assessed at the posttreatment follow-up ≥ 1 year in CLP patients. Full articles were retrieved from abstracts or titles that appear to meet the inclusion criteria or lacked sufficient detail for immediate exclusion. Once full articles were collected, they were again reviewed considering more detailed inclusion criteria for a final selection decision. A methodologic quality assessment tool was utilized.Results:Thirty abstracts/titles met the initial search criteria, and 13 articles were finally selected. Overall, methodologic quality scores were high in only one randomized clinical trial. After maxillary advancement with DO in CLP patients, the long-term horizontal relapse in A-point was less than 15% in eight studies and between 20% and 25% in four studies. The study that was judged as a high-quality study reported 8.2% horizontal relapse in A-point. The relapse rate was higher in DO with external distracter device than DO with internal distracter device.Conclusions:Current evidence suggests maxillary advancement with DO has good stability in CLP patients with moderate and severe maxillary hypoplasia. 相似文献
92.
Park JC Kim JC Kim BK Cho KS Im GI Kim BS Kim CS 《Journal of periodontal research》2012,47(5):645-654
Park J‐C, Kim J.C, Kim B‐K, Cho K‐S, Im G‐I, Kim B‐S, Kim C‐S. Dose‐ and time‐dependent effects of recombinant human bone morphogenetic protein‐2 on the osteogenic and adipogenic potentials of alveolar bone‐derived stromal cells. J Periodont Res 2012; 47: 645–654. © 2012 John Wiley & Sons A/S Background and Objective: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a well‐known growth factor that can induce robust bone formation, and recent studies have shown that rhBMP‐2‐induced osteogenesis is closely related to adipogenesis. The aim of the present study was to determine the dose‐ and time‐dependent effects of rhBMP‐2 on the osteogenic and adipogenic differentiation of human alveolar bone‐derived stromal cells (hABCs) in vivo and in vitro. Material and Methods: hABCs were isolated and cultured, and then transplanted using a carrier treated either with or without rhBMP‐2 (100 μg/mL) into an ectopic subcutaneous mouse model. Comprehensive histologic and histometric analyses were performed after an 8‐wk healing period. To further understand the dose‐dependent (0, 10, 50, 200, 500 and 1000 ng/mL) and time‐dependent (0, 3, 5, 7 and 14 d) effects of rhBMP‐2 on osteogenic and adipogenic differentiation, in vitro osteogenic and adipogenic differentiation of hABCs were evaluated, and the expression of related mRNAs, including those for alkaline phosphatase, osteocalcin, bone sialoprotein, peroxisome‐proliferator‐activated receptor gamma‐2 and lipoprotein lipase, were assessed using quantitative RT‐PCR. Results: rhBMP‐2 significantly promoted the osteogenic and adipogenic differentiation of hABCs in vivo, and gradually increased both the osteogenic and adipogenic potential in a dose‐ and time‐dependent manner with minimal deviation in vitro. The expression of osteogenesis‐ and adipogenesis‐associated mRNAs were concomitantly up‐regulated by rhBMP‐2. Conclusion: The findings of the present study showed that rhBMP‐2 significantly enhanced the adipogenic as well as the osteogenic potential of hABCs in dose‐ and time‐dependent manner. The control of adipogenic differentiation of hABCs should be considered when regenerating the alveolar bone using rhBMP‐2. 相似文献
93.
Liu CK Liu P Meng FW Deng BL Xue Y Mao TQ Hu KJ 《The British journal of oral & maxillofacial surgery》2012,50(4):356-360
The aim of this study was to examine the role of the lateral peterygoid muscle in the reconstruction of the shape of the condyle during healing of a sagittal fracture of the mandibular condyle. Twenty adult sheep were divided into 2 groups: all had a unilateral operation on the right side when the anterior and posterior attachments of the discs were cut, and an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of the condylar neck. Ten sheep had the lateral pterygoid muscle cut, and the other 10 sheep did not. Sheep were killed at 4 weeks (n=2 from each group), 12 weeks (n=4), and 24 weeks (n=4) postoperatively. Computed tomograms (CT) were taken before and after operations. We dissected the joints, and recorded with the naked eye the shape, degree of erosion, and amount of calcification of the temporomandibular joint (TMJ). In the group in which the lateral peterygoid muscle had not been cut the joints showed overgrowth of new bone and more advanced ankylosis. Our results show that the lateral pterygoid muscle plays an important part in reconstructing the shape of the condyle during the healing of a sagittal fracture of the mandibular condyle, and combined with the dislocated and damaged disc is an important factor in the aetiology of traumatic ankylosis of the TMJ. 相似文献
94.
95.
de Gijt JP van der Wal KG Kleinrensink GJ Smeets JB Koudstaal MJ 《The British journal of oral & maxillofacial surgery》2012,50(6):519-522
The Rotterdam mandibular distractor (RMD) is a slim, rigid, boneborne distractor for use in midline distraction of the mandible. We did a biomechanical study to compare the RMD with the Trans Mandibular Distractor-flex (TMD-flex). This included an anatomical biomechanical study that was conducted on 9 dentate human cadaveric heads using both the RMD and the TMD-flex. In the vertical plane less tipping was measured in the RMD group than in the TMD-flex group. Significantly less skeletal tipping was found in the horizontal plane in the RMD group (P=0.021). There was minimal difference in the intercondylar distance between the groups. As the amount of lateral displacement of the condyle was similar in both groups and there was less rotational movement in the RMD group, the TMD-flex would be expected to increase stress on the temporomandibular joint. As a result of the increased parallel widening in the vertical plane, more basal bone is being created and less relapse is expected using the RMD. The study design involves an in vitro anatomical model and conclusions must be drawn with care. At present clinical studies are under way and results will follow. 相似文献
96.
目的基于FGFR1蛋白靶点筛选淫羊藿中抗骨质疏松的药效成分。方法采用维甲酸灌胃14 d复制大鼠骨质疏松模型,给予淫羊藿提取物进行干预;采用Western blotting法检测各组大鼠股骨FGFR1蛋白的表达,用UPLC-Q-TOF-MS确认提取物中化学成分。基于FGFR1靶点进行分子虚拟对接筛选药效成分。结果淫羊藿能够改善大鼠骨质疏松症状,并提高FGFR1蛋白的表达。淫羊藿提取物中指认出23种化合物,其中淫羊藿苷、淫羊藿次苷I、箭藿苷C可与FGFR1可以有效对接。结论淫羊藿中淫羊藿苷、淫羊藿次苷I、箭藿苷C可能通过上调FGFR1发挥抗骨质疏松作用。 相似文献
97.
We studied the effects of long-term (20-day) simulated microgravity (clinostatic exposure) and osteogenic differentiation stimuli on cultured mesenchymal stromal precursor cells isolated from human bone marrow. Clinostatic exposure significantly reduced proliferative activity of mesenchymal stem cells in comparison with the static and dynamic control, increased the number of large flat cells in the culture, and stimulated migration activity of cells. Phenotypic studies of surface antigens (CD90, CD54, CD106, CD105, CD34, CD45, class 1 HLA) during clinostatic exposure of mesenchymal stem cell cultures showed differences in their expression between experimental and control groups. Studies of osteogenesis of precursor cell showed that cell differentiation potential can be directed towards osteogenesis by a combination of clinostatic exposure and differentiation stimuli. The results confirm gravity sensitivity of human bone marrow precursor cells and open new vistas for understanding of the mechanisms of bone tissue loss in humans under conditions of space mission. 相似文献
98.
Distraction Osteogenesis (DO) has become a treatment alternative to treat severe craniofacial skeletal dysplasias. A rigid external distraction (RED) device has been successfully used to advance the maxilla as well as the maxillary, orbital and forehead complex (monobloc) in children as young as two years, adolescents and adults. This approach has provided predictable and stable results. It can be applied by itself or as an adjunct to traditional orthognathic and craniofacial surgical procedures. The technical aspects, including planning, surgical and orthodontic procedures, required to properly apply the technique are presented. For this severe group of patients the technique has been found to be simpler and safer than traditional surgical methods. Maxillary and midfacial advancement through distraction has been found to be extremely stable in the patients in whom the technique was used. The reasons for stability are discussed as well as the observed morphologic changes in the facial soft tissues, velopharyngeal mechanism and airway. However, challenges remain to be solved to improve all distraction techniques and the need for collaboration between researchers and clinicians is emphasized to maximize the benefits of this already promising and rewarding approach. 相似文献
99.
龚燕平 《中国现代医学杂志》2022,(10):1-6
脂肪因子脂联素与骨代谢关系密切,并进行了大量的细胞、模型动物及人群的调查研究。虽然许多研究证实了脂联素对成骨的正向调节作用,但是研究结果不完全一致。目前仍未能完全了解脂联素信号通路在年龄、疾病及骨修复中的重要性。该述评探讨了脂联素对成骨作用的初步研究结论,脂联素不同异构体、不同受体的可能作用通路,以及老年人群的脂联素生物学改变。探究脂联素对骨骼生物学的调控作用有助于药物开发和非药物(生活方式)干预方式的研究。针对脂联素信号进行干预,可能有助于维护衰老过程中的骨健康和损伤后的骨骼修复。 相似文献
100.
类器官(organoids)来源于自体的组织及干细胞,是通过体外3D培养后形成的细胞团块,这种团块具有原始组织及器官的三维结构,并保留了相对应的功能和遗传特征。由于其具有模拟特定机体器官的发育和疾病发生发展的潜能,这一模型在多种药物的筛选和分子机制研究中拥有更多的优势。近年来,已有实验表明骨髓源性间充质干细胞(BMSCs)通过3D培养及成骨分化可以形成骨的类器官,并可以植入机体发挥特定的作用。这种骨类器官模型的构建,不仅可以为骨质疏松等相关疾病研究提供更多方法,还在骨组织移植及修复等组织工程学中发挥重要作用。本文就BMSCs成骨分化的类器官相关3D模型研究进展作一综述,为BMSCs成骨分化的类器官的基础和临床研究提供更多理论依据和思路。 相似文献