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71.
Limb shortening is a problem associated with surgery for osteosarcoma of the lower extremity in adolescents, as the tumors frequently occur near the epiphysis. Herein we report the use of a less invasive stabilization system (LISS) and an intermittent fixation method to preserve the growth function of epiphysis in an 11-year-old patient with an osteosarcoma of the distal femur.The 11-year-old male presented with left knee enlargement and pain for 2 weeks, and magnetic resonance imaging (MRI) and biopsy were consistent with osteosarcoma of the left distal femur. After preoperative chemotherapy, en bloc tumor resection was performed with margins based on MRI findings preserving the epiphyseal growth plate, the tumor cavity was filled with inactivated bone and bone cement, and a LISS was used to stabilize the femur. Aggressive postoperative chemotherapy was given. Approximately 105 weeks after surgery radiography showed that the distal end of the plate had moved superior to the epiphysis along with bone growth. Locking screws were placed in the distal part of the LISS plate to stabilize the re-implanted bone, and external fixation was not needed.The patient was able to walk with the crutches 1 week postoperatively, and bear weight on the extremity 6 weeks postoperatively. At 6 years after surgery, the patient''s height had increased 52 cm, shortening of the affected limb was only 1 cm, and the circumference of the affected limb was 2 cm smaller than that of the contralateral limb. There was no significant discomfort in the affected limb, and there was no gait abnormality. The patient could jump and run, and could participate in sports including basketball and badminton to the same degree as his peers.In summary, the novel method of bone reconstruction and fixation provided good results in a child with an osteosarcoma of the distal femur. This fixation method preserves the osteogenic function of the epiphysis and restored bone integrity simultaneously, and provides good functional recovery. 相似文献
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75.
The significance of hepatobiliary scintigraphy (HBS) for hepatic graft function assessment was established mostly on retrospective studies and was not widely recognized due to the lack of quantitative data and variation in accuracy. This prospective study was performed to investigate the effectiveness of quantitative HBS for assessing hepatocyte dysfunction and biliary complication in liver transplant recipients.In 57 recipients who had undergone orthotopic liver transplantation, a total of 67 dynamic 99mTc-EHIDA scans were performed and quantitative parameters including the hepatocyte extraction fraction (HEF), time to maximum hepatic radioactivity (Tmax), and time for peak activity to decrease by 50% (T1/2) were calculated. The scintigraphic results based on the 3 parameters were compared against the final diagnosis. A ROC curve analysis was carried out to identify the cutoff value of Tmax for diagnosis of biliary stricture. Correlation between the parameters of postoperative HBS and conventional biochemical liver function indices were also analyzed.Quantitative 99mTc-EHIDA HBS had an overall sensitivity of 94.12% (16/17), specificity of 93.33% (42/45), and diagnostic accuracy of 93.55% (58/62) for detecting hepatocyte dysfunction and biliary complication in liver transplant recipients. The recommended cutoff value of Tmax for diagnosis of post-transplant biliary stricture was set at 15.75 min with a sensitivity of 100.0% and a specificity of 94.0%. The scintigraphic parameters (HEF, Tmax) were statistically significantly associated with the conventional liver function parameters.Quantitative 99mTc-EHIDA HBS offers a noninvasive imaging modality with high sensitivity and specificity to diagnose hepatocyte dysfunction as well as distinguish between patients with or without biliary stricture following liver transplantation. Furthermore, HEF and Tmax values obtained from dynamic HBS show good correlation with conventional liver function parameters. 相似文献
76.
Sirt5 is known to functionally regulate mitochondrial proteins by altering posttranslational modifications, including lysine desuccinylation. While roles for Sirt5 as either a tumor promoter or suppressor, or in chemoresistance, have been implicated in other cancers, the function of Sirt5 in cutaneous melanoma has not been well examined. Therefore, to determine whether Sirt5 is necessary for BrafV600E‐mediated melanoma formation and/or disease progression, we crossed a genetically engineered murine melanoma model (TyrCreERT2/+; BrafLSL‐V600E/+; Ptenflox/flox) to Sirt5?/? knockout animals. In addition, we tested for synergism with a selective BRAF (V600E) inhibitor in Sirt5?/? mouse melanoma cells. Taken together, this report demonstrates that, in these models, Sirt5 is dispensable for BrafV600E‐mediated cutaneous melanoma formation and growth in vivo, and does not improve sensitivity to a selective BRAF inhibitor. 相似文献
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目的:探讨电子线对胰岛素生长因子-1家族蛋白表达的影响,为研究辐射对肝脏的早期损伤提供依据。方法:采用电子线照射小鼠,照射剂量为1、2、4 Gy,用Western blot法检测照射后12、48和72 h小鼠肝脏中胰岛素生长因子1受体(IGF-1R)、胰岛素生长因子结合蛋白1(IGFBP1)、胰岛素生长因子结合蛋白4(IGFBP4)和胰岛素生长因子1(IGF-1)蛋白表达水平的改变。结果:照射剂量为1 Gy时,与对照组相比,IGF-1蛋白在照射后48 h时表达增加,IGFBP1、IGFBP4和IGF1R蛋白的表达在照射后12、48和72 h均表达减少。照射剂量为2 Gy时,IGF-1和IGFBP4蛋白在照射后48 h时表达增加,其余时间点表达减少。IGFBP1蛋白在照射后12 h时表达增加,48和72 h时表达减少。IGF1R蛋白在照射后3个时间点均呈现为表达减少。照射剂量4 Gy时,肝脏中IGF-1、IGFBP1和IGFBP4蛋白均表达减少,IGF1R蛋白在照射后12 h时表达增加,48、72 h时均表达减少(均为P < 0.05)。结论:电子线照射后小鼠肝脏中胰岛素生长因子-1家族蛋白多以下调表达为主,与前期基因表达的结果相一致,有可能作为反映放射性工作人员早期肝脏损伤的生物标志物之一。 相似文献
79.
目的 探讨microRNA-613调控细胞周期蛋白依赖性激酶14(CDK14)通路来抑制老年胶质瘤患者瘤细胞增殖和侵袭的机制。方法 购自上海北诺生物科技有限公司的人脑胶质瘤细胞株U251共24株,分为shNC组、shmicroRNA-613组、Vector组、microRNA-613组,每组各6株; Western Blotting法和qRT-PCR法检测敲减microRNA-613和过表达microRNA-613后的人脑胶质瘤细胞株U251中CDK14蛋白表达水平,CCK-8细胞增殖实验、Transwell小室实验验证敲除microRNA-613和过表达microRNA-613后U251细胞的增殖、侵袭能力。结果 人胶质瘤细胞株U251敲减microRNA-613后CDK14蛋白表达增加(P<0.05); 人胶质瘤细胞株U251过表达microRNA-613后CDK14蛋白表达减少(P<0.05); 转染第24、36、48 h microRNA-613组U251细胞增殖率P<0.05); microRNA-613组U251细胞侵袭能力>Vector组,shNC组>shmicroRNA-613组(P<0.05)。结论 microRNA-613可通过调控CDK14信号转导通路来抑制人脑胶质瘤细胞U251增殖、转移。 相似文献
80.
Zhengxian Huang Nan Xie Haichao Liu Yuehan Wan Yue Zhu Ming Zhang Yifan Tao Han Zhou Xiqiang Liu Jinsong Hou Cheng Wang 《Journal of oral pathology & medicine》2019,48(9):788-798
It has been suggested that tumour‐infiltrating lymphocytes (TILs) are associated with the progression of oral squamous cell carcinoma (OSCC). However, the prognostic value of TILs is inconclusive due to the heterogeneity of immune cells within the tumour microenvironment. In this meta‐analysis, we aimed to assess the prognostic value of TILs in OSCC. The PubMed, Cochrane, Embase, Scopus and Web of Science databases were searched up to April 20, 2019, and 33 studies were ultimately included in this meta‐analysis. Our pooled meta‐analysis showed that high infiltration of CD8+ TILs, CD45RO+ TILs and CD57+ TILs favoured better overall survival (OS). However, high infiltration of CD68+ macrophages and CD163+ macrophages was associated with poor prognosis in OSCC. These findings suggest that CD8+ TILs, CD45RO+ TILs, CD57+ TILs, CD68+ macrophages and CD163+ macrophages might serve as novel prognostic factors and therapeutic targets in OSCC. 相似文献