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??Objective    To investigate the effect of tooth movement at different time after the repair of alveolar bone defects. Methods    Defective alveolar bone model was established on one side in forty white rabbits??which were filled with bone meal and attached with Bio-Gide membrane as experiment sides. The other side was performed routine tooth extraction as control. Track the mandibular second molar in both sides respectively in 1 week??1 month??2 months and 3 months after operation. One month later??the distance between the mandibular second molar and third molar was measured with electronic vernier caliper in the experiment side and control side. The mandibular tissue was made paraffin section and hematoxylin eosin staining. Three views of the periodontal ligament in a third place of the mesial roots of the second molar was randomly chosen to count the total number of osteoclasts. Paired-t test analysis was made to evaluate the displacement of the mandibular second molar in experiment and control side??and to evaluate the number of osteoclasts in two side. Results    In Group 1w and Group 1 m??the displacement of the mandibular second molar in experiment group was smaller than that in the control side??P??0.05??. There was no statistical significance in Group 2 m and Group 3 m. The number of osteoclasts in the experiment side was less than the control group in Group 1 w and Group1 m??P??0.05??. No statistical significance in Group 2 m and Group 3 m was found. Conclusion    Orthodontic treatment can be performed two months after the repair of alveolar bone defects.  相似文献   
33.
Fibrous dysplasia is a non‐neoplastic developmental process that affects the craniofacial bones, characterized by painless enlargement as a result of bone substitution by abnormal fibrous tissue. Postzygotic somatic activating mutations in the GNAS1 gene cause fibrous dysplasia and have been extensively investigated, as well as being helpful in the differential diagnosis of the disease. Fibrous dysplasia may involve one (monostotic) or multiple bones (polyostotic), sporadically or in association with McCune‐Albright syndrome, Jeffe‐Lichenstein syndrome, or Mazabreud syndrome. This review summarizes the current knowledge on fibrous dysplasia, emphasizing the value of integrating the understanding of its molecular pathogenesis with the clinical, radiological, and histopathological features. In addition, we address important aspects related to the differential diagnosis and patient management.  相似文献   
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目的:研究非霍奇金淋巴瘤(non-Hodgkin' s lymphoma,NHL)骨髓侵犯患者骨髓病灶中间隙连接蛋白(connexin,Cx)43表达情况。 方法:选取我院确诊的非霍奇金淋巴瘤骨髓侵犯患者26例,骨髓组织中查见呈灶性分布且已通过免疫组化证实为反应性淋巴细胞增生的患者9例,正常骨髓组织10例行免疫组化染色,根据阳性率及阳性程度评分后进行统计学分析。 结果:Cx43在NHL样本中的阳性率(30.8%)低于在反应性淋巴细胞增生样本(88.9%)及正常样本(100%)中的阳性率,差异有统计学意义(P<0.05)。而反应性淋巴细胞增生样本和正常样本间Cx43阳性率无统计学意义(P>0.05),但反应性淋巴细胞增生样本的阳性积分明显低于正常样本(P<0.05)。结论:非霍奇金淋巴瘤骨髓侵犯时病灶处Cx43表达情况显著低于反应性淋巴细胞增生及正常骨髓组织。  相似文献   
36.
Chondrosarcoma is the second most common form of bone cancer and is characterized by its ability to produce an extracellular matrix of the cartilage. High-grade chondrosarcoma is highly aggressive and can metastasize to other parts of the body. Chondrosarcoma is resistant to both conventional chemotherapy and radiotherapy; hence, the current main treatment is still surgical resection. Doxorubicin (Dox) has been shown to significantly improve patient survival compared with untreated chondrosarcoma. However, for patients with metastasis, surgical resection alone can hardly treat them. In addition, drug resistance is one of the leading causes of death in patients with chondrosarcoma. Secreted proteins can mediate cell-cell interactions in the cancer microenvironment, which may be associated with the development of drug resistance. In the present study, chondrosarcoma cells were treated with Dox, the conditioned medium was then collected and changes in secreted proteins were analyzed using the antibody array. Results showed that the Dox-treated group had the highest secretion of basic fibroblast growth factor (bFGF), indicating the effect of bFGF on Dox sensitivity in chondrosarcoma. Furthermore, lentiviral-mediated knockdown and treatment of exogenous recombinant protein were employed to further investigate the effect of bFGF on Dox resistance. Results demonstrated that bFGF can promote the expression of X-ray repair cross-complementing protein 5 (XRCC5), leading to Dox resistance. Secreted bFGF is likely to be detected in serum, in addition to being a biomarker for predicting Dox resistance, the combination of Dox and bFGF/XRCC5 blockers may be a new therapeutic strategy to improve the efficacy of Dox in future.  相似文献   
37.
目的:自体骨髓移植联合MHC单倍体相合淋巴细胞治疗急性髓性白血病的治疗效果和安全性。方法:以40例急性髓性白血病患者作为研究对象,随机分为两组各20例,研究组患者使用自体骨髓移植联合MHC单倍体相合淋巴细胞进行治疗,对照组单用自体骨髓移植进行治疗。结果:两组患者的造血系统都得到重建,重建时间以及并发症的发生均没有显著差异。而研究组患者复发率显著降低,且复发时间明显地长于对照组患者。研究组患者3年累积无病生存率明显地高于对照组患者,且差异具有统计学意义。结论:自体骨髓移植联合MHC单倍体相合淋巴细胞治疗能够有效控制急性髓性白血病病情,降低其复发,延长患者生存期。  相似文献   
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正枕骨、寰椎和枢椎共同构成了枕颈部活动的结构功能单位,即枕颈交界区~([1-2])。炎症、创伤、肿瘤及畸形等因素会导致枕颈交界区失稳,从而引起颈脊髓或神经根的损伤、麻痹及难以忍受的疼痛,甚至危及生命~([3-4])。后路内固定融合技术是治疗枕颈部失稳的重要手段,目前常用术式为枕骨螺钉技术,该技术较钢丝固定技术有更好的生物力学稳定  相似文献   
40.
Disseminated tumor cells (dTCs) can frequently be detected in the bone marrow (BM) of colorectal cancer (CRC) patients, raising the possibility that the BM serves as a reservoir for metastatic tumor cells. Identification of dTCs in BM aspirates harbors the potential of assessing therapeutic outcome and directing therapy intensity with limited risk and effort. Still, the functional and prognostic relevance of dTCs is not fully established. We have previously shown that CRC cell clones can be traced to the BM of mice carrying patient-derived xenografts. However, cellular interactions, proliferative state and tumorigenicity of dTCs remain largely unknown. Here, we applied a coculture system modeling the microvascular niche and used immunofluorescence imaging of the murine BM to show that primary CRC cells migrate toward endothelial tubes. dTCs in the BM were rare, but detectable in mice with xenografts from most patient samples (8/10) predominantly at perivascular sites. Comparable to primary tumors, a substantial fraction of proliferating dTCs was detected in the BM. However, most dTCs were found as isolated cells, indicating that dividing dTCs rather separate than aggregate to metastatic clones—a phenomenon frequently observed in the microvascular niche model. Clonal tracking identified subsets of self-renewing tumor-initiating cells in the BM that formed tumors out of BM transplants, including one subset that did not drive primary tumor growth. Our results indicate an important role of the perivascular BM niche for CRC cell dissemination and show that dTCs can be a potential source for tumor relapse and tumor heterogeneity.  相似文献   
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