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51.
目的通过建立去势比格犬模型,观察绝经早期腹部脂肪变化规律,并通过对脂肪与骨代谢相关血清学指标的测量与分析,探讨脂肪及骨代谢的关键影响因素。方法选取6只成年雌性比格犬进行去势术,分别在术前、术后4个月、6个月、10个月进行腰椎定量CT(quantatitive computed tomography,QCT)腹部脂肪面积、骨密度(bone mineral density,BMD)、MRI腰椎骨髓脂肪含量及血清学指标的检测,比较不同时间各指标的变化趋势及关系。结果比格犬腹内脂肪面积(visceral fat area,VFA)、皮下脂肪面积(subcutaneous fat area,SFA)、腹部总脂肪面积(total fat area,TFA)在术后6个月、10个月均增加(P0.05),术后10个月VFA增加百分比均值为84.39%,且为三者中最大;术后比格犬BMD并未明显降低。体重、BMD、瘦素(leptin,LP)、VFA、高密度脂蛋白(high-density lipoprotein,HDL)与SFA相关。SFA、体重、低密度脂蛋白(low-density lipoprotein,LDL)、内脏脂肪素(visfatin,VFN)与BMD相关。结论去势比格犬模型可用于研究绝经后雌激素缺乏所引起的脂肪代谢变化,但短期内BMD并未明显丢失,骨、脂肪代谢之间存在交互作用。 相似文献
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53.
֣��ǫ�������̣��Ŷ�ǿ 《中国实用口腔科杂志》2015,8(5):271-273
??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
54.
Thaís dos Santos Fontes Pereira Carolina Cavalieri Gomes Peter A Brennan Felipe Paiva Fonseca Ricardo Santiago Gomez 《Journal of oral pathology & medicine》2019,48(1):3-9
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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目的探讨胫前动脉踝上穿支皮瓣修复足踝部软组织缺损的临床疗效。方法回顾性研究2018年4月至2019年6月采用胫前动脉踝上穿支皮瓣修复足踝部软组织缺损19例的资料,其中男11例,女8例;年龄为21~75岁,平均39岁。根据前踝上穿支皮瓣解剖学基础,按照足踝部软组织缺损大小和形状,在小腿下端前外侧设计并切取皮瓣转位修复创面。切取胫前动脉踝上穿支皮瓣面积为6.0 cm×5.0 cm^14.0 cm×8.0 cm,均为带蒂皮瓣转位。根据皮瓣成活、感染控制、弹性色泽、外观形态、供区瘢痕、皮肤感觉、患者认可等情况,对患者足踝部软组织缺损的修复情况进行综合评价。结果本组19例皮瓣全部成活,软组织缺损、肌腱、骨质及钢板外露均得以修复。供区均I期愈合。术后门诊随访2~16个月,皮瓣血运良好,颜色接近周围正常皮肤,臃肿不明显,患者对外观表示满意;供区皮片愈合良好,无明显增生、挛缩及溃疡,踝关节功能良好。结论胫前动脉踝上穿支皮瓣是修复足踝部软组织缺损较为理想的方法之一,手术操作简便,穿支较恒定,血供可靠,具有一定的临床应用价值。 相似文献
59.
《The ocular surface》2020,18(4):901-911
PurposeThe long-term success of visual rehabilitation in patients with severe conjunctival scarring is reliant on the reconstruction of the conjunctiva with a suitable substitute. The purpose of this study is the development and investigation of a re-epithelialized conjunctival substitute based on porcine decellularized conjunctiva (PDC).MethodsPDC was re-epithelialized either with pre-expanded human conjunctival epithelial cells (PDC + HCEC) or with a human conjunctival explant placed directly on PDC (PDC + HCEx). Histology and immunohistochemistry were performed to evaluate epithelial thickness, proliferation (Ki67), apoptosis (Caspase 3), goblet cells (MUC5AC), and progenitor cells (CK15, ΔNp63, ABCG2). The superior construct (PDC + HCEx) was transplanted into a conjunctival defect of a rabbit (n = 6). Lissamine green staining verified the epithelialization in vivo. Orbital tissue was exenterated on day 10 and processed for histological and immunohistochemical analysis to examine the engrafted PDC + HCEx. A human-specific antibody was used to detect the transplanted cells.ResultsFrom day-14 in vitro onward, a significantly thicker epithelium and greater number of cells expressing Ki67, CK15, ΔNp63, and ABCG2 were noted for PDC + HCEx versus PDC + HCEC. MUC5AC-positive cells were found only in PDC + HCEx. The PDC + HCEx-grafted rabbit conjunctivas were lissamine-negative during the evaluation period, indicating epithelial integrity. Engrafted PDC + HCEx showed preserved progenitor cell properties and an increased number of goblet cells comparable to those of native conjunctiva.ConclusionPlacing and culturing a human conjunctival explant directly on PDC (PDC + HCEx) enables the generation of a stable, stratified, goblet cell-rich construct that could provide a promising alternative conjunctival substitute for patients with extensive conjunctival stem and goblet cell loss. 相似文献
60.
Marie Ohata Susumu Fujiwara Ai Yoshioka Hiroshi Nagai Shintaro Sugita Nozomi Yamano Yusuke Inoue Chikako Nishigori 《Pediatric dermatology》2019,36(6):997-998
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy. 相似文献