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带袢纽扣钢板与传统螺钉固定治疗Lisfranc韧带损伤的临床疗效观察
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作者 杨安 黄旭龙 +1 位作者 王勇 杨海波 《宁夏医学杂志》 CAS 2024年第3期226-229,共4页
目的通过对比分析带袢纽扣钢板与传统螺钉固定治疗Lisfranc韧带损伤的临床疗效。方法回顾性分析46例涉及Lisfranc韧带损伤患者的临床资料,其中观察组23例,均接受带袢纽扣钢板固定治疗,对照组23例,均采用传统螺钉固定治疗。从一般资料、... 目的通过对比分析带袢纽扣钢板与传统螺钉固定治疗Lisfranc韧带损伤的临床疗效。方法回顾性分析46例涉及Lisfranc韧带损伤患者的临床资料,其中观察组23例,均接受带袢纽扣钢板固定治疗,对照组23例,均采用传统螺钉固定治疗。从一般资料、围术期参数、Lisfranc关节间距、疼痛、中足功能、术后1年AOFAS评分的优良率以及术后并发症发生率等方面进行对比分析,对其临床疗效进行综合评价。结果2组患者年龄、性别、BMI、受伤至手术时间、术中出血量比较差异无统计学意义(P>0.05)。观察组在术后6个月及1年时,疼痛更少,差异有统计学意义(P<0.05)。在术后1年时,观察组足功能表现更好,差异有统计学意义(P<0.05)。观察组共出现2例术后并发症(含切口浅表感染及腓深神经损伤各1例),对照组共9例出现术后并发症(1例切口浅表感染、2例螺钉断裂、3例Lisfranc关节再分离及3例创伤性关节炎),2组数据比较差异有统计学意义(P<0.05)。结论带袢纽扣钢板固定牢靠,术后患足功能恢复较好,并发症少。 展开更多
关键词 Lisfranc韧带损伤 带袢纽扣钢板 传统螺钉 内固定 临床疗效
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Differences and similarities in radial growth of Betula species to climate change
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作者 Di Liu yang an +3 位作者 Zhao Li Zhihui Wang Yinghui Zhao Xiaochun Wang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期176-187,共12页
Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)forests.However,the specific ways in which their growth is affected by warm temperatures and drought remain... Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)forests.However,the specific ways in which their growth is affected by warm temperatures and drought remain unclear.To address this issue,60 and 62 tree-ring cores of B.platyphylla and B.costata were collected in Yichun,China.Using dendrochronological methods,the response and adaptation of these species to climate change were examined.A“hysteresis effect”was found in the rings of both species,linked to May–September moisture conditions of the previous year.Radial growth of B.costata was positively correlated with the standardized precipitation-evapotranspiration index(SPEI),the precipitation from September to October of the previous year,and the relative humidity in October of the previous year.Growth of B.costata is primarily restricted by moisture conditions from September to October.In contrast,B.platyphylla growth is mainly limited by minimum temperatures in May–June of both the previous and current years.After droughts,B.platyphylla had a faster recovery rate compared to B.costata.In the context of rising temperatures since 1980,the correlation between B.platyphylla growth and monthly SPEI became positive and strengthened over time,while the growth of B.costata showed no conspicuous change.Our findings suggest that the growth of B.platyphylla is already affected by warming temperatures,whereas B.costata may become limited if warming continues or intensifies.Climate change could disrupt the succession of these species,possibly accelerating the succession of pioneer species.The results of this research are of great significance for understanding how the growth changes of birch species under warming and drying conditions,and contribute to understanding the structural adaptation of mixed broadleaved-Korean pine(Pinus koraiensis)forests under climate change. 展开更多
关键词 Tree rings Betula platyphylla Betula costata Climate response Moving correlation Extreme drought
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Development and validation of a nomogram model for predicting the risk of gallstone recurrence after gallbladder-preserving surgery
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作者 Peng Liu Yong-Wei Chen +5 位作者 Che Liu Yin-Tao Wu Wen-Chao Zhao Jian-Yong Zhu yang an Nian-Xin Xia 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第3期288-292,共5页
Background:The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladderpreserving surgery.This study aimed to investigate the risk factors for gallstone recurrence after gallbladder-pres... Background:The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladderpreserving surgery.This study aimed to investigate the risk factors for gallstone recurrence after gallbladder-preserving surgery and to establish an individualized nomogram model to predict the risk of gallstone recurrence.Methods:The clinicopathological and follow-up data of 183 patients who were initially diagnosed with gallstones and treated with gallbladder-preserving surgery at our hospital from January 2012 to January 2019 were retrospectively collected.The independent predictive factors for gallstone recurrence following gallbladder-preserving surgery were identified by multivariate logistic regression analysis.A nomogram model for the prediction of gallstone recurrence was constructed based on the selected variables.The C-index,receiver operating characteristic(ROC)curve and calibration curve were used to evaluate the predictive power of the nomogram model for gallstone recurrence.Results:During the follow-up period,a total of 65 patients experienced gallstone recurrence,and the recurrence rate was 35.5%.Multivariate logistic regression analysis revealed that the course of gallstones>2 years[odds ratio(OR)=2.567,95%confidence interval(CI):1.270-5.187,P=0.009],symptomatic gallstones(OR=2.589,95%CI:1.059-6.329,P=0.037),multiple gallstones(OR=2.436,95%CI:1.133-5.237,P=0.023),history of acute cholecystitis(OR=2.778,95%CI:1.178-6.549,P=0.020)and a greasy diet(OR=2.319,95%CI:1.186-4.535,P=0.014)were independent risk factors for gallstone recurrence after gallbladder-preserving surgery.A nomogram model for predicting the recurrence of gallstones was established based on the above five variables.The results showed that the C-index of the nomogram model was 0.692,suggesting it was valuable to predict gallstone recurrence.Moreover,the calibration curve showed good consistency between the predicted probability and actual probability.Conclusions:The nomogram model for the prediction of gallstone recurrence might help clinicians develop a proper treatment strategy for patients with gallstones.Gallbladder-preserving surgery should be cautiously considered for patients with high recurrence risks. 展开更多
关键词 GALLSTONE Gallbladder-preserving surgery RECURRENCE Risk factors NOMOGRAM
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水下控制系统CAN总线技术方案研究 被引量:1
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作者 范玉杨 苏锋 +2 位作者 杨安 李斌 何宁强 《自动化仪表》 CAS 2023年第4期55-59,64,共6页
控制器局域网(CAN)最初为汽车应用设计的数字协议,现在已经广泛应用于楼宇自动化、机械制造、安全监控、汽车工业、航空工业等领域。目前,国内尚未有油气开发领域水下控制系统CAN总线技术应用的规范。通过对CAN总线物理层、CAN-open协... 控制器局域网(CAN)最初为汽车应用设计的数字协议,现在已经广泛应用于楼宇自动化、机械制造、安全监控、汽车工业、航空工业等领域。目前,国内尚未有油气开发领域水下控制系统CAN总线技术应用的规范。通过对CAN总线物理层、CAN-open协议的研究,结合道路汽车领域的ISO 11898和CAN-open的CAN-in-Automation(CiA)系列规范,探讨了在深水油气开发领域典型水下采气树CAN总线数据监测的工程设计方法,提出了水下控制系统中CAN总线完整的技术方案。该方案包括速率选择、接口界面、拓扑、线缆类型、数据协议等。随着水下控制系统国产化步伐加快,深入研究并掌握CAN技术,为水下电子模块国产化提供了嵌入式开发的技术方向,可对深水监测仪表及水下控制模块国产化研究的顺利进行起到促进作用。 展开更多
关键词 水下控制系统 控制器局域网总线 水下仪表 水下监测 CAN-open协议
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Revision rhinoplasty for contracted nose:A systematic review and meta-analysis
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作者 Yiming Wang Guanhuier Wang +1 位作者 Yonghuan Zhen yang an 《Chinese Journal Of Plastic and Reconstructive Surgery》 2023年第2期100-108,共9页
Background:This study aimed to review treatments and evaluate the aesthetic outcomes,complications,and reoperation rates regarding surgical correction for a postoperative contracted nose.Methods:PubMed,MEDLINE,and Emb... Background:This study aimed to review treatments and evaluate the aesthetic outcomes,complications,and reoperation rates regarding surgical correction for a postoperative contracted nose.Methods:PubMed,MEDLINE,and Embase databases were searched for studies detailing aesthetic outcomes and complications of surgical correction of a contracted nose.Surgical procedures,adjuvant treatment,outcomes,and complications were synthesized and analyzed.Results:Nine articles encompassing 376 patients were included in the systematic review,and six articles(198 participants)were included in the meta-analysis.The most frequently used graft material was the autologous rib cartilage(61.1%).Surgical procedures were heterogeneous in these studies.The nasolabial angle reduced by 9.52°(95%confidence interval(CI):(-11.95,-7.09),P<0.0001),and the nasal length increased significantly(standardized mean difference(SMD)=2.25,95%CI:(1.26,2.23),P<0.00001).However,the evidence was insufficient to determine a significant change in the columellar-labial angle(SMD=-0.95,95%CI:(-2.19,0.29),P=0.13)and columellar-lobular angle(SMD=2.39,95%CI:(-1.20,5.97),P=0.19).Aesthetic dissatisfaction(12.5%)and infection(4.5%)were the most commonly reported complications.Reoperation was performed in 5.3%of patients.Conclusion:Surgical correction can increase the nasal length,reduce the nasolabial angle,and have a low reoperation rate.No significant improvement in the columellar-labial or columellar-lobular angle was observed. 展开更多
关键词 Nasal deformity Contracted nose RHINOPLASTY Postoperative complication META-ANALYSIS Systematic review
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Role of adipose-derived stem cells in breast cancer
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作者 Wanwen Dang Junhao Wu +2 位作者 Guanhuier Wang Yonghuan Zhen yang an 《Chinese Journal Of Plastic and Reconstructive Surgery》 2023年第2期73-79,共7页
The clinical use of fat grafts for breast reconstruction post-mastectomy or radiotherapy has the disadvantages of limited retention and survival rates.To solve this problem,adipose-derived stem cells(ADSCs)have been s... The clinical use of fat grafts for breast reconstruction post-mastectomy or radiotherapy has the disadvantages of limited retention and survival rates.To solve this problem,adipose-derived stem cells(ADSCs)have been suggested as an alternative cell source for breast reconstruction,because they are simple to access,have low immunogenicity,and support the survival of mature adipose grafts.However,despite their outstanding properties,the use of ADSCs in patients with breast cancer is controversial,and the oncological safety of this method has been questioned.The biological effects of ADSCs on breast cancer are complex,and clinical research on ADSC-assisted fat grafting is limited.Here,we review the current experimental findings on the effects of ADSCs on breast cancer,mainly focusing on the role of ADSCs in breast cancer proliferation and growth processes,such as epithelial-mesenchymal transition(EMT)and angiogenesis.We also discuss the safety of ADSCs in clinical breast reconstruction. 展开更多
关键词 Adipose-derived stem cells Breast cancer Breast reconstruction Cell-assisted lipotransfer
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基于时间线性拟合的地缆架空混合线路的行波故障定位
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作者 杨岸 许鹏坤 《重庆工商大学学报(自然科学版)》 2024年第3期72-80,共9页
目的研究n段地缆架空混合输电线路中行波故障定位问题,提出一种基于时间线性拟合的行波故障定位方法。方法首先对故障区域进行判断,确定故障所在的区域,其次再将不同波阻抗线路进行归一化处理,减少因波速不同而产生的测距误差,最后使用... 目的研究n段地缆架空混合输电线路中行波故障定位问题,提出一种基于时间线性拟合的行波故障定位方法。方法首先对故障区域进行判断,确定故障所在的区域,其次再将不同波阻抗线路进行归一化处理,减少因波速不同而产生的测距误差,最后使用时间线性拟合的方法对故障进行精确定位。结果解决了初始行波波头识别困难的问题,也减小了行波速度随传输距离变化而变化带来的测距误差问题。结论在MATLAB/Simulink中搭建一个500 kV的地缆架空混合输电线路仿真模型,实验的验证结果表明此故障定位方法能够有效地解决因行波速度不同而导致的双端行波测距方法不适用问题,最终实现对故障点的精确定位。 展开更多
关键词 混合线路 线性拟合 归一化处理 双端行波 故障定位
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苹果砧木CX5组织培养体系的建立
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作者 严家帝 杨安 +2 位作者 田玉凤 韩晓蕾 张彩霞 《中国果树》 2024年第5期39-44,共6页
以苹果半矮化砧CX5的休眠枝条茎段和4月底至6月初的新生枝条茎段为试验材料,采用离体组织培养方法,研究了适宜CX5组培快繁的外植体类型、灭菌方式、灭菌时间,以及不同植物生长调节剂浓度对增殖培养的影响。结果表明:适合用作灭菌的CX5... 以苹果半矮化砧CX5的休眠枝条茎段和4月底至6月初的新生枝条茎段为试验材料,采用离体组织培养方法,研究了适宜CX5组培快繁的外植体类型、灭菌方式、灭菌时间,以及不同植物生长调节剂浓度对增殖培养的影响。结果表明:适合用作灭菌的CX5外植体类型为新生枝条茎段,其外植体褐化率和污染率都相对较低;外植体0.1%HgCl2灭菌时间控制在6min左右,伤害最小;CX5茎段腋芽诱导培养基为MS+0.75mg/L6-BA+0.3mg/LIBA,适宜组培苗增殖继代的培养基为MS+0.7mg/L6-BA+0.5mg/LIBA,生根培养基为1/2MS+0.2mg/LIAA。初步构建了CX5组培快繁技术体系。 展开更多
关键词 苹果半矮化砧 CX5 茎段 组织培养
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一种星载固态功率放大器用400W二次电源设计
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作者 罗聃 赵恒飞 +5 位作者 陈伟伟 杨桉 吴江牛 段力冬 赵普 汪蕾 《空间电子技术》 2024年第2期94-100,共7页
为了满足导航卫星系统对于固态功率放大器大功率、高可靠性、轻量化的需求,文章采用移相全桥同步整流变换电路加反激变换电路匹配的拓扑方案,设计了一种星载L频段固态放大器用400W二次电源,并详细给出了二次电源拓扑结构及设计原理分析... 为了满足导航卫星系统对于固态功率放大器大功率、高可靠性、轻量化的需求,文章采用移相全桥同步整流变换电路加反激变换电路匹配的拓扑方案,设计了一种星载L频段固态放大器用400W二次电源,并详细给出了二次电源拓扑结构及设计原理分析。文章重点对变压器热耗进行分析,为了更好地进行变压器散热设计,该方案创新性采用灌封主功率变压器散热方案,灌封变压器的温度从104℃降低为85.5℃,散热相比有明显改善。同时给出了实物环路测试、电性能指标对比测试以及热平衡与热仿真对比测试,电源效率92.8%,环路的相位裕量42°,增益裕度26dB。测试结果表明设计的二次电源在实现高效率大功率输出的同时,有效地实现器件的一级降额散热,满足高可靠性的批产需求。 展开更多
关键词 卫星导航 400W二次电源 移相全桥 变压器散热
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湖北省人工林现状及变化动态分析
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作者 杨安 曹爱平 +2 位作者 冯顺柏 潘文娟 张之勇 《湖北林业科技》 2024年第2期62-66,74,共6页
根据湖北省2013—2022年森林资源动态监测数据,分析了全省人工林现状及面积、结构等变化动态,结果显示,湖北省人工林面积稳步增加,用材林面积大幅增长,主要树种发生演替,同时也存在着树种结构不优、生态稳定性不强等问题,通过分析人工... 根据湖北省2013—2022年森林资源动态监测数据,分析了全省人工林现状及面积、结构等变化动态,结果显示,湖北省人工林面积稳步增加,用材林面积大幅增长,主要树种发生演替,同时也存在着树种结构不优、生态稳定性不强等问题,通过分析人工林变化原因及存在的主要问题,结合当前林业发展新形势,提出开展国土绿化攻坚、推进森林质量提升、持续提升固碳能力等全省人工林发展的对策建议。 展开更多
关键词 人工林 优势树种 变化动态 质量提升
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Novel serum microRNAs panel on the diagnostic and prognostic implications of hepatocellular carcinoma 被引量:9
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作者 yang an Song Gao +4 位作者 Wen-Chao Zhao Bao-an Qiu Nian-Xin Xia Peng-Jun Zhang Zhen-Ping Fan 《World Journal of Gastroenterology》 SCIE CAS 2018年第24期2596-2604,共9页
AIM To determine a panel of serum micro RNAs(mi RNAs) that could be used as novel biomarkers for diagnosis of hepatocellular carcinoma(HCC).METHODS We initially screened 9 out of 754 serum mi RNAs by Taq Man Low Densi... AIM To determine a panel of serum micro RNAs(mi RNAs) that could be used as novel biomarkers for diagnosis of hepatocellular carcinoma(HCC).METHODS We initially screened 9 out of 754 serum mi RNAs by Taq Man Low Density Array in two pooled samples respectively from 35 HCC and 35 normal controls, and then validated individually by RT-qP CR in another 114 patients and 114 controls arranged in two phases. The changes of the selected mi RNAs after operation and their prognostic value were examined.RESULTS miR-375, miR-10 a, miR-122 and miR-423 were found to be significantly higher in HCC than in controls(P < 0.0001), and the area under the receiver-operating-characteristic curve for the 4-miR NA panel was 0.995(95%CI: 0.985-1). All the four mi RNAs were significantly reduced after surgical removal of the tumors(P < 0.0001), while still higher than normal controls(at least P < 0.05)CONCLUSION The four serum miR NAs(miR-375, miR-10 a, miR-122 and miR-423) could potentially serve as novel biomarkers for the diagnostic and prognostic of HCC. 展开更多
关键词 HEPATOCELLULAR carcinoma MICRORNAS SERUM BIOMARKER diagnosis
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Memory stem T cells generated by Wnt signaling from blood of human renal clear cell carcinoma patients 被引量:4
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作者 Cihui Yan Jingjing Chang +6 位作者 Xinmiao Song Fan Yan Wenwen Yu yang an Feng Wei Lili yang Xiubao Ren 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第1期109-120,共12页
Objective: Memory stem T cells(Tscm) have attracted attention because of their enhanced self-renewal, multipotent capacity, and anti-tumor capacities. However, little is known about Tscm in patients with renal clear c... Objective: Memory stem T cells(Tscm) have attracted attention because of their enhanced self-renewal, multipotent capacity, and anti-tumor capacities. However, little is known about Tscm in patients with renal clear cell carcinoma(RCC) and the role of Wnt signaling in these cells. We evaluated Tscm from RCC patients concerning their activation of Wnt signaling in vitro and explored the mechanism of preferential survival.Methods: Flow cytometry identified surface markers and cytokines produced from accumulated Tscm in the presence of the glycogen synthase kinase beta inhibitor TWS119. Apoptosis was evaluated after induction using tumor necrosis factor-alpha.Immunofluorescence and Western blot analyses were used to investigate the activation of the nuclear factor-kappa B(NF-КB)pathway.Results: RCC patients had a similar percentage of CD4^+ and CD8^+ Tscm as healthy donors. Activation of Wnt signaling by TWS119 resulted in the accumulation of Tscm in activated T cells, but reversal of differentiated T cells to Tscm was not achieved.Preferential survival of Tscm was associated with increased anti-apoptotic ability mediated downstream of the NF-КB activation pathway.Conclusions: The finding that Tscm can accumulate by Wnt signaling in vitro in blood from RCC patients will help in devising new cancer therapy strategies of Tscm-based adoptive immunotherapy, such as dendritic cell-stimulated Tscm, and T cell receptor or chimeric antigen receptor-engineered Tscm. 展开更多
关键词 MEMORY STEM T CELL TWS119 WNT signaling apoptosis RENAL CLEAR CELL carcinoma
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Transforming growth factor-β and peripheral regulatory cells are negatively correlated with the overall survival of hepatocellular carcinoma 被引量:4
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作者 yang an Song Gao +4 位作者 Wen-Chao Zhao Bao-an Qiu Nian-Xin Xia Peng-Jun Zhang Zhen-Ping Fan 《World Journal of Gastroenterology》 SCIE CAS 2018年第25期2733-2740,共8页
AIM To understand the cellular and molecular changes inperipheral blood that can lead to the development of hepatocellular carcinoma(HCC) and provide new methods for its diagnosis and treatment.METHODS Peripheral bloo... AIM To understand the cellular and molecular changes inperipheral blood that can lead to the development of hepatocellular carcinoma(HCC) and provide new methods for its diagnosis and treatment.METHODS Peripheral blood mononuclear cells were isolated from the peripheral blood of HCC patients and normal controls and then analyzed by flow cytometry. The percentage of transforming growth factor-β(TGF-β)+ regulatory cells(Tregs) in the peripheral blood was measured, and the expression of TGF-β was also determined. Then, the relationship between the changes and the 5-year survival of patients was analyzed. In addition, recombinant human TGF-β(rh TGF-β) and recombinant human interleukin-6 were added to stimulate the cultured cells, and their effects on HCC were evaluated.RESULTS The expression of TGF-β and the percentage of TGF-β+ Tregs in the peripheral blood of HCC patients increased significantly compared with normal controls. Compared with the low TGF-β expression group, the high TGF-β expression group had a significantly lower 5-year survival rate, and the same result was found in the two TGF-β+ Treg groups, suggesting that TGF-β and TGF-β+ Tregs were negatively correlated with the overall survival of the patients. In addition, rh TGF-β promoted the growth of tumor cells and induced high expression levels of IL-6, which further promoted tumor proliferation.CONCLUSION The results showed that TGF-β may promote tumor growth and proliferation by inducing the production of IL-6, and TGF-β and TGF-β+ Tregs may serve as new markers for predicting a poor prognosis in HCC. 展开更多
关键词 Hepatocellular carcinoma TRANSFORMING growth factor-β REGULATORY CELLS PERIPHERAL blood MONONUCLEAR CELLS INTERLEUKIN-6
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Droplet digital polymerase chain reaction assay for methylated ring finger protein 180 in gastric cancer 被引量:1
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作者 Guang-Hong Guo Yi-Bin Xie +1 位作者 Tao Jiang yang an 《World Journal of Gastrointestinal Oncology》 SCIE 2022年第10期2038-2047,共10页
BACKGROUND Gastric cancer(GC)is one of the most prevalent malignant tumors that endangers human health.Early diagnosis is essential for improving the prognosis and survival rate of GC patients.Ring finger protein 180(... BACKGROUND Gastric cancer(GC)is one of the most prevalent malignant tumors that endangers human health.Early diagnosis is essential for improving the prognosis and survival rate of GC patients.Ring finger protein 180(RNF180)is involved in the regulation of cell differentiation,proliferation,apoptosis,and tumorigenesis,and aberrant hypermethylation of CpG islands in the promoter is strongly associated with the occurrence and development of GC.Thus,methylated RNF180 can be used as a potential biomarker for GC diagnosis.AIM To use droplet digital polymerase chain reaction(ddPCR)to quantify the methylation level of the RN180 gene.A reproducible ddPCR assay to detect methylated RNF180 from trace DNA was designed and optimized.METHODS The primer and probe were designed and selected,the conversion time of bisulfite was optimized,the ddPCR system was adjusted by primer concentration,amplification temperature and amplification cycles,and the detection limit of ddPCR was determined.RESULTS The best conversion time for blood DNA was 2 h 10 min,and that for plasma DNA was 2 h 10 min and 2 h 30 min.The results of ddPCR were better when the amplification temperature was 56°C and the number of amplification cycles was 50.Primer concentrations showed little effect on the assay outcome.Therefore,the primer concentration could be adjusted according to the reaction system and DNA input.The assay required at least 0.1 ng of input DNA.CONCLUSION In summary,a ddPCR assay was established to detect methylated RNF180,which is expected to be a new diagnostic biomarker for GC. 展开更多
关键词 Gastric cancer Ring finger protein 180 DNA methylation Droplet digital polymerase chain reaction
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微板块与深部地幔LLSVP的遥相关作用
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作者 曹现志 李三忠 +4 位作者 索艳慧 戴黎明 杨安 王鹏程 刘金平 《岩石学报》 SCIE EI CAS CSCD 北大核心 2023年第3期659-669,共11页
基于海洋地质地球物理观测建立的板块构造理论意味着板块和浅部地幔共同演化,然而地幔底部尤其是大型横波低速异常区(LLSVP)与板块(尤其微板块)运动和演化之间是否存在关联仍有争议。一些研究认为LLSVP长期保持稳定,而另一些模型则认为... 基于海洋地质地球物理观测建立的板块构造理论意味着板块和浅部地幔共同演化,然而地幔底部尤其是大型横波低速异常区(LLSVP)与板块(尤其微板块)运动和演化之间是否存在关联仍有争议。一些研究认为LLSVP长期保持稳定,而另一些模型则认为它与各级板块存在相互作用。为此,本文通过总结前人成果,并基于近期发表的板块重建和地幔对流模型进行进一步分析,探讨微板块运动和LLSVP的演化关系。模拟结果表明,微板块与大板块类似,俯冲后通常会下沉至核幔边界。微幔块会推动地幔底部热的物质聚集并形成大的热化学结构。该热化学结构与层析成像揭示的LLSVP基本吻合。下地幔径向流速场和温度场的二阶结构与地表速度场散度的二阶结构随时间的移动轨迹相似,表明深浅部圈层的耦合演化,但是下地幔结构演化一般会滞后于浅表。在微幔块推挤之下,地幔柱优先沿着地幔底部热化学结构的边缘形成,且有时会被推至热化学结构的内部。地幔柱上升至浅部后,能够导致岩石圈弱化甚至裂解或板块边界跃迁,形成微板块。因此,地幔底部LLSVP不是稳定或静止的,而是与微板块动态协同演化,并通过地幔柱与浅表板块边界发生遥相关,从而控制微板块生成场所。 展开更多
关键词 微板块构造 地幔对流 大型横波低速异常区 深浅耦合 地球动力学
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Analog modeling of sand slope stability with different precipitation conditions 被引量:1
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作者 Tangjin Ye Qiang Xie +2 位作者 Ying Wang yang an Jiang Jin 《Journal of Modern Transportation》 2018年第3期200-208,共9页
Water–sand flow triggered by rainfall is the dominant mechanism for instability and failure of sand slopes. To further analyze the stability state of sand on a slope under different rainfall conditions, the initiatio... Water–sand flow triggered by rainfall is the dominant mechanism for instability and failure of sand slopes. To further analyze the stability state of sand on a slope under different rainfall conditions, the initiation conditions and flow characteristics of water–sand flows are studied. Based on the theory of equilibrium forces and hydrological dynamics, a 1:100-scale analog model is built and verified with field observation data. The results indicate three dynamic stabilization stages of the sand slope under different weather conditions: dry sand, wet sand, and water–sand flow. Water–sand flows are triggered easilyunder short duration and heavy rainfall conditions. The rainfall threshold required to initiate water–sand flow is 4.14 mm/h. Rainfall amount and duration required to initiate water–sand flow decrease with fine sand content increasing. A sand head that develops at the front of the water–sand flow results in a flow along the edge of the sand debris flow and a ‘‘tree root’’ flow morphology. Modelingresults are consistent with theoretical analysis and field observations. 展开更多
关键词 PRECIPITATION Analog modeling Sand slope Water–sand flow Stability
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Factors influencing myogenic differentiation of adipose-derived stem cells and their application in muscle regeneration 被引量:1
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作者 Na Liu Guanhuier Wang +5 位作者 Yonghuan Zhen Yujia Shang Fangfei Nie Lingjuan Zhu Zhenmin Zhao yang an 《Chinese Journal Of Plastic and Reconstructive Surgery》 2022年第3期126-132,共7页
Skeletal muscle regeneration mainly depends on muscle satellite cells;however,these cells are not sufficient for supporting repair and regeneration in volumetric muscle loss(VML),Duchenne muscular dystrophy,and other ... Skeletal muscle regeneration mainly depends on muscle satellite cells;however,these cells are not sufficient for supporting repair and regeneration in volumetric muscle loss(VML),Duchenne muscular dystrophy,and other muscle injuries or muscle diseases.As such,much work has been conducted in recent years to search for myogenic stem cells.Adipose-derived stem cells(ADSCs)have a wide range of sources,rapid growth,and multi-directional differentiation potential,and have become vital candidates for muscle regeneration.Multiple factors influence the myogenic differentiation capacity of ADSCs.This paper reviews the regulatory aspects and possible factors that have been identified in recent years to affect myogenic differentiation of ADSCs.Based on these factors,gene editing,and perfusion concepts,a method was proposed to achieve maximal differentiation efficiency of ADSCs.This study focused on the application of ADSCs in muscle regeneration and disease.Based on the importance of myogenic differentiation of ADSCs for the repair and regeneration of muscle damage,this study provides a basis for future research surrounding the efficient induction of myogenic differentiation of ADSCs in vitro. 展开更多
关键词 Adipose-derived stem cells Muscle regeneration Muscle diseases Myogenic differentiation Regulatory factors
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Use of Autologous Costal Cartilage Combined with Expanded Polytetrafluoroethylene in Asian Rhinoplasty 被引量:2
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作者 yang an Jianfang ZHAO +3 位作者 Lu LU Yonghuan ZHEN Xiaojie Tan Dong LI 《Chinese Journal Of Plastic and Reconstructive Surgery》 2020年第2期69-77,共9页
Background The corresponding author's experience and recent methods employed in autologous costal cartilage grafts combined with expanded polytetrafluoroethylene(ePTFE)in Asian rhinoplasty were presented in this s... Background The corresponding author's experience and recent methods employed in autologous costal cartilage grafts combined with expanded polytetrafluoroethylene(ePTFE)in Asian rhinoplasty were presented in this study.Objectives The purpose of this study was to assess the outcomes of rhinoplasty performed on patients using autogenous costal cartilage grafts combined with an ePTFE implant.Methods Seventy-five rhinoplasty cases with autologous costal cartilage grafts and an ePTFE implant were retrospectively reviewed.Graft types,complications associated with the graft itself or graft harvesting,surgical outcomes,and patient satisfaction were assessed.Results The mean follow-up time post-operation was 13.5 months.A total of 42/75 patients underwent revision surgeries.Graft-related complications were found in 8%of cases,including two warped graft and four infection cases.Three individuals with infections had mild graft resorption.One patient with an infection removed the implant.Graft exposure,mobility,and substantial resorption were not recorded.A total of two cases underwent revision procedures for infection and perforation,respectively.Chest incision lengths for graft harvesting averaged 2.1 cm.No pneumothorax or significant donor-site pain was found.Donor-site scars were negligible,although two cases had hypertrophic chest scars.In general,functional and esthetic outcomes were mostly satisfactory among the assessed patients.Conclusions Rhinoplasty using autologous rib cartilage provides adequate support and sufficient cartilage amounts for correcting nasal contouring.Meanwhile,ePTFE alone for nasal dorsum augmentation safely achieves satisfactory outcomes.Rib cartilage rhinoplasty performed by an experienced surgeon yields excellent,long-lasting results with minimal risk;however,the potential for infection should be considered following revision surgery. 展开更多
关键词 Asian rhinoplasty autologous costal cartilage EPTFE IMPLANT
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Multi-fidelity Bayesian algorithm for antenna optimization
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作者 LI Jianxing yang an +2 位作者 TIan Chunming YE Le CHEN Badong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第6期1119-1126,共8页
In this work,the multi-fidelity(MF)simulation driven Bayesian optimization(BO)and its advanced form are proposed to optimize antennas.Firstly,the multiple objective targets and the constraints are fused into one compr... In this work,the multi-fidelity(MF)simulation driven Bayesian optimization(BO)and its advanced form are proposed to optimize antennas.Firstly,the multiple objective targets and the constraints are fused into one comprehensive objective function,which facilitates an end-to-end way for optimization.Then,to increase the efficiency of surrogate construction,we propose the MF simulation-based BO(MFBO),of which the surrogate model using MF simulation is introduced based on the theory of multi-output Gaussian process.To further use the low-fidelity(LF)simulation data,the modified MFBO(M-MFBO)is subsequently proposed.By picking out the most potential points from the LF simulation data and re-simulating them in a high-fidelity(HF)way,the M-MFBO has a possibility to obtain a better result with negligible overhead compared to the MFBO.Finally,two antennas are used to testify the proposed algorithms.It shows that the HF simulation-based BO(HFBO)outperforms the traditional algorithms,the MFBO performs more effectively than the HFBO,and sometimes a superior optimization result can be achieved by reusing the LF simulation data. 展开更多
关键词 antenna optimization Bayesian optimization(BO) multiple-output Gaussian process multi-fidelity(MF) low-fidelity(LF)simulation reuse
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Enhanced photon emission by field emission resonances and local surface plasmon in tunneling junction
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作者 李健梅 郝东 +4 位作者 孙丽欢 唐向前 安旸 单欣岩 陆兴华 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期455-459,共5页
We investigated the photon emission spectra on Ag(111)surface excited by tunneling electrons using a low temperature scanning tunneling microscope in ultrahigh vacuum.Characteristic plasmon modes were illustrated as a... We investigated the photon emission spectra on Ag(111)surface excited by tunneling electrons using a low temperature scanning tunneling microscope in ultrahigh vacuum.Characteristic plasmon modes were illustrated as a function of the bias voltage.The one electron excitation process was revealed by the linear relationship between the luminescence intensity and the tunneling current.Luminescence enhancement is observed in the tunneling regime for the relatively high bias voltages,as well as at the field emission resonance with bias voltage increased up to 9 V.Presence of a silver(Ag)nanoparticle in the tunneling junction results in an abnormally strong photon emission at the high field emission resonances,which is explained by the further enhancement due to coupling between the localized surface plasmon and the vacuum.The results are of potential value for applications where ultimate enhancement of photon emission is desired. 展开更多
关键词 scanning tunneling microscopy LUMINESCENCE surface plasmon field emission resonance
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