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阶段相关生物标志物PPIA、YWHAZ和GRP78是结直肠癌的潜在预后指标 被引量:3
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作者 彭娅 贺艳玲 +5 位作者 张军玲 陈智远 成瑾瑜 杨瑜明 沈守荣 孙英男 《生命科学仪器》 2020年第1期40-48,共9页
目的:结直肠癌(colorectal cancer,CRC)是常见消化系统恶性肿瘤之一,目前,其发病率和死亡率日益上升。迄今为止,结直肠癌的确切发病机制尚不清楚,大量文献表明,结直肠癌的发病机制是一个多基因参与的多阶段的过程,故探索检测结直肠癌某... 目的:结直肠癌(colorectal cancer,CRC)是常见消化系统恶性肿瘤之一,目前,其发病率和死亡率日益上升。迄今为止,结直肠癌的确切发病机制尚不清楚,大量文献表明,结直肠癌的发病机制是一个多基因参与的多阶段的过程,故探索检测结直肠癌某些阶段的生物标志物对于提高患者生存率具有重要意义。方法:本研究使用2D-DIGE、MALDI-TOF/TOF MS、免疫组化等方法,构建结直肠癌组织芯片,通过生存分析,来探究PPIA(肽基脯氨酰顺反异构酶A)、YWHAZ(14-3-3蛋白zeta/delta)和GRP78(78kDa葡萄糖调节蛋白前体)的表达水平是否和CRC的发生和发展有关。结果:在本研究中,通过蛋白质组学分析表明,与正常结直肠粘膜相比,结直肠癌中的PPIA、YWHAZ和GRP78蛋白表达上调。在结直肠癌发生的所有阶段(TNM I-IV期),PPIA均显著上调,PPIA表达越高,预后越差(P=0.002)。YWHAZ在I期明显上调,与临床分期呈负相关(T1-2/T3-4,P=0.003),可能是早期CRC的特异性生物标志物。GRP78在第三和第四阶段上调,提示它参与了CRC淋巴结转移和其他远处转移。此外,在CRC患者中PPIA、YWHAZ和GRP78的高表达与低生存期显著相关(分别为P=0.002、0.024和0.010)。结论:阶段生物标志物PPIA、YWHAZ和GRP78与结直肠癌的发生有显著关系,这些蛋白可能是结直肠癌的潜在预后指标。 展开更多
关键词 结直肠癌 阶段相关生物标志物 蛋白质组学 预后
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微生物燃料电池阳极材料修饰研究进展 被引量:5
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作者 周亚 彭新红 +3 位作者 阮国岭 张颖 黄鹏飞 姚德翠 《水处理技术》 CAS CSCD 北大核心 2017年第3期9-13,19,共6页
总结了近年来微生物燃料电池(MFCs)阳极种类及其修饰方法,主要包括增加阳极表面积,提高电化学活性生物的粘附量或接触位点、或者降低阳极内阻、减小电子传递阻力等方面。认为较低的输出功率、较高的操作成本是限制其实际应用的主要障碍... 总结了近年来微生物燃料电池(MFCs)阳极种类及其修饰方法,主要包括增加阳极表面积,提高电化学活性生物的粘附量或接触位点、或者降低阳极内阻、减小电子传递阻力等方面。认为较低的输出功率、较高的操作成本是限制其实际应用的主要障碍。未来的重点是开发研究电导性高、稳定性强、比表面积大、生物相容性好的阳极材料,而对MFCs阳极材料的不断探索研究也将推动MFCs实际应用的进程。 展开更多
关键词 微生物燃料电池 阳极 修饰 研究进展
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光和热驱动金催化邻炔基酚与芳基重氮盐的反应:两种机制相似性和差异性的理论研究
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作者 金蕊 郭昕怡 +3 位作者 彭灵雅 刘向洋 方维海 崔刚龙 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第1期87-99,I0036-I0092,I0118,共71页
实验上发现,邻炔基酚与芳基重氮盐在热催化和光催化条件下反应可生成不同的产物,然而反应机理尚不清晰.本文采用MSCASPT2和密度泛函理论方法研究了热和光驱动反应的催化机理.结果表明,热催化和光催化反应的初始历程相同,都是在HCO3-协... 实验上发现,邻炔基酚与芳基重氮盐在热催化和光催化条件下反应可生成不同的产物,然而反应机理尚不清晰.本文采用MSCASPT2和密度泛函理论方法研究了热和光驱动反应的催化机理.结果表明,热催化和光催化反应的初始历程相同,都是在HCO3-协助下由Au(Ⅰ)催化剂和邻炔基酚反应得到乙烯基Au(Ⅰ)中间体.在此过程中,Au(l)催化剂与邻炔基酚反应克服14.8 kcal/mol的能垒生成结构扭曲的配合物,此时邻炔基酚的C≡C三键被活化.随后,乙烯基Au(Ⅰ)中间体和芳基重氮盐形成复合物,热催化和光催化反应开始分叉.在黑暗条件下,反应克服15.7 kcal/mol的能垒后生成最终的热催化产物,此时芳基重氮盐的末端N原子直接与乙烯基Au(Ⅰ)中间体的C原子成键.在光照条件下,复合物首先弛豫到激发单重态,经9.8×10^(9)s^(-1)的高效系间窜跃过程衰变到T_(1)态.在T_(1)态,克服7.8 kcal/mol的能垒完成脱氮反应,产生与乙烯基Au(Ⅰ)中间体的Au原子具有相互作用的芳基自由基,随后发生系间窜跃过程到达基态.在基态形成最终的光催化产物.本研究为理解Au(Ⅰ)催化剂与芳基重氮盐的热催化和光催化反应提供了重要的机理见解,发现了无辐射跃迁在光催化反应中的关键作用. 展开更多
关键词 光氧化还原催化 过渡金属配合物 密度泛函理论 反应机理 Au(Ⅰ)催化剂 光物理 芳基重氮盐 邻炔基酚
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胆囊结石非手术治疗的研究进展 被引量:2
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作者 陈亚东 蔡海斌 +1 位作者 刘鹏 彭娅 《世界华人消化杂志》 CAS 2018年第25期1511-1516,共6页
胆囊结石(gallstone, GS)是消化系统常见的疾病之一,胆固醇、胆汁酸的代谢失衡导致胆固醇沉积与GS的发生关系密切.目前指南建议对有GS症状的患者行胆囊切除术,但仍存在部分GS患者无手术指征、手术条件或者不接受手术治疗,这部分人群极... 胆囊结石(gallstone, GS)是消化系统常见的疾病之一,胆固醇、胆汁酸的代谢失衡导致胆固醇沉积与GS的发生关系密切.目前指南建议对有GS症状的患者行胆囊切除术,但仍存在部分GS患者无手术指征、手术条件或者不接受手术治疗,这部分人群极可能从非手术治疗中获益.目前指南对于GS的非手术治疗并未太多提点,临床医生对非手术治疗未置予重视.本文查阅国内外近年来发表的相关文献,拟对GS的非手术治疗进行系统综述,旨在让临床医生熟悉GS的非手术治疗方法,并结合临床实际推广应用. 展开更多
关键词 胆囊切除术 体外冲击波碎石术 依折麦布 他汀类 核受体 CAJAL细胞
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石油钻机绞车三种刹车系统的优缺点研究 被引量:3
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作者 张亚鹏 《石化技术》 CAS 2018年第8期82-83,共2页
石油钻机绞车刹车系统应用优势各异,需要综合多方面数据信息选择适宜的技术应用内容,从而提高石油钻机绞车刹车系统应用有效性。本文根据石油钻机绞车刹车系统特点,对其3种主要及辅助刹车系统进行逐一分析,并对其不同种类的刹车系统优... 石油钻机绞车刹车系统应用优势各异,需要综合多方面数据信息选择适宜的技术应用内容,从而提高石油钻机绞车刹车系统应用有效性。本文根据石油钻机绞车刹车系统特点,对其3种主要及辅助刹车系统进行逐一分析,并对其不同种类的刹车系统优缺点做出阐述,以此为石油钻机绞车刹车系统应用提供相关的理论内容参考建议。 展开更多
关键词 石油 钻机 绞车 刹车系统 优缺点
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三配位Au(I)配合物热激活延迟荧光机理的量子力学/分子力学研究:晶体环境的关键作用
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作者 李子问 彭灵雅 +2 位作者 宋秀芳 高远君 崔刚龙 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2023年第2期175-185,I0007-I0025,I0054,I0055,共32页
近年来,三配位Au(I)配合物的热激活延迟荧光现象引起了人们的关注.然而,其发光机理尚不清楚.本文采用密度泛函理论、含时密度泛函理论以及量子力学/分子力学方法研究了Au(I)配合物在气相和晶体中的激发态性质.在这两种环境下,S_(1)和T_... 近年来,三配位Au(I)配合物的热激活延迟荧光现象引起了人们的关注.然而,其发光机理尚不清楚.本文采用密度泛函理论、含时密度泛函理论以及量子力学/分子力学方法研究了Au(I)配合物在气相和晶体中的激发态性质.在这两种环境下,S_(1)和T_(1)激发态主要涉及HOMO和LUMO,表现出明显的金属-配体电荷转移和配体内电荷转移特征.HOMO和LUMO的空间分离有助于缩小S_(1)和T_(1)之间的能隙,加速T_(1)到S_(1)的反向系间窜跃.在300K时,反向系间窜跃速率比磷光发射速率快,实现了热激活延迟荧光.但在77 K时,反向系间窜跃通道阻塞,热激活延迟荧光消失,因此低温时实验上只观测到磷光现象.这项工作有助于进一步了解有机金属配合物的热激活延迟荧光发光机理. 展开更多
关键词 热激活延迟荧光 Au(I)配合物 密度泛函理论 激发态 环境效应
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贵州经济后发山区土地利用变化及其地形分异特征
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作者 余军林 罗娅 +1 位作者 彭睿文 罗旭琴 《贵州科学》 2017年第4期32-39,共8页
以贵州省丹寨县为研究区,运用遥感解译、GIS空间分析和数理统计分析方法,分析经济后发山区的土地利用变化及其地形分异特征,为实现经济后发山区的土地资源可持续利用提供参考。结果表明:1)2013年到2015年,丹寨县土地利用变化迅速,平均... 以贵州省丹寨县为研究区,运用遥感解译、GIS空间分析和数理统计分析方法,分析经济后发山区的土地利用变化及其地形分异特征,为实现经济后发山区的土地资源可持续利用提供参考。结果表明:1)2013年到2015年,丹寨县土地利用变化迅速,平均土地利用变化动态度为17.07%;耕地和林地面积减少,建设用地、草地和水域增加;建设用地增加最快,其用地面积由97.76 km2增加到243.65 km2,增加了145.89 km2;主要变化类型有林地转为耕地,耕地转为林地,耕地转为建设用地,以及林地转为建设用地等4种形式。2)土地利用变化主要发生在海拔为400 m^1200 m地带,坡度为6°~25°的缓坡和斜坡地带,坡向为45°~135°和225°~315°的半阳坡地带。各地带都以林地与耕地之间的转换、林地和耕地向建设用地的转化为主。平地和平缓地是耕地转为建设用地最显著的区域。对于山地面积占76%的丹寨来说,这些地带的土地质量相对优良,土地生产力较高。因此,在今后的经济建设工作中,要加强这些地带的土地资源保护,提高其土地利用的生态经济效益。 展开更多
关键词 经济后发山区 土地利用变化 空间分异 地形 丹寨县
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Intervertebral disc degeneration and bone density in degenerative lumbar scoliosis: a comparative study between patients with degenerative lumbar scoliosis and patients with lumbar stenosis 被引量:19
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作者 DING Wen-yuan yaNG Da-long CAO Lai-zhen SUN ya-peng ZHANG Wei XU Jia-xin ZHANG Ying-ze SHEN Yong 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第23期3875-3878,共4页
Degenerative lumbar scoliosis is common in older patients. Decreased bone density and the degeneration of intervertebral discs are considered to be correlated with degenerative lumbar scoliosis. A means of quantifying... Degenerative lumbar scoliosis is common in older patients. Decreased bone density and the degeneration of intervertebral discs are considered to be correlated with degenerative lumbar scoliosis. A means of quantifying the retative signal intensity for degenerative disc disease has not been previously discussed. The purpose of this study was to compare bone mineral density and intervertebral disc degeneration between degenerative lumbar scoliosis and lumbar spinal stenosis patients in a nine-year retrospective study. Methods From January 2001 to August 2010, 96 patients with degenerative lumbar scoliosis were retrospectively enrolled and 96 patients with lumbar spinal stenosis were selected as controls. Cobb angle, height of the apical disc and the contiguous disc superiorly and inferiorly on convex and concave sides, the height of the convex and concave side of the apical and the contiguous vertebral body superiorly and inferiorly were measured in the scoliosis group. The height of L2/L3, L3/L4, L4/L5 discs and the height of L2/L4 vertebral body was measured in the control group. The grade of intervertebral disc degeneration was evaluated using T2Wl sagittal images in both groups. The bone density of lumbar vertebrae was measured with dual-energy X-ray. Results In scoliosis group, the intervertebral disc height on the convex side was greater than the height on the concave side (P 〈0.001). The vertebral body height on the convex side was greater than the height on the concave side (P=0.016) There was a significant difference between the scoliosis group and the control group (P=0.003), and between T-value and the rate of osteoporosis between the two groups (both P 〈0.001). Results were verified using multiple linear regression analysis. Conclusions Degenerative lumbar scoliosis is accompanied by height asymmetry between the intervertebral disc and vertebral body regarding the convex and concave surfaces. There is a positive correlation between the angle of scoliosis and the disc index, the degre 展开更多
关键词 degenerative scoliosis OSTEOPOROSIS intervertebral disc LUMBAR DEGENERATION
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Blood neutrophil-lymphocyte ratio predicts survival after hepatectomy for hepatocellular carcinoma: A propensity score-based analysis 被引量:18
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作者 Hao-Jie yang Zhe Guo +5 位作者 Yu-Ting yang Jing-Hang Jiang ya-peng Qi Ji-Jia Li Le-Qun Li Bang-De Xiang 《World Journal of Gastroenterology》 SCIE CAS 2016年第21期5088-5095,共8页
AIM: To investigate whether an elevated preoperative neutrophil-to-lymphocyte ratio(NLR) can predict poor survival in patients with hepatocellular carcinoma(HCC).METHODS: We retrospectively reviewed 526 patients with ... AIM: To investigate whether an elevated preoperative neutrophil-to-lymphocyte ratio(NLR) can predict poor survival in patients with hepatocellular carcinoma(HCC).METHODS: We retrospectively reviewed 526 patients with HCC who underwent surgery between 2004 and 2011.RESULTS: Preoperative NLR ≥ 2.81 was an independent predictor of poor disease-free survival(DFS, P < 0.001) and overall survival(OS, P = 0.044). Compared with patients who showed a preoperative NLR < 2.81 and postoperative increase, patients who showed preoperative NLR ≥ 2.81 and postoperative decrease had worse survival(DFS, P < 0.001; OS, P < 0.001). Among patients with preoperative NLR ≥ 2.81, survival was significantly higher among those showing a postoperative decrease in NLR than among those showing an increase(DFS, P < 0.001; OS, P < 0.001). When elevated, alpha-fetoprotein(AFP) provided no prognostic information, and so preoperative NLR ≥ 2.81 may be a good complementary indicator of poor OS whenever AFP levels are low or high.CONCLUSION: Preoperative NLR ≥ 2.81 may be an indicator of poor DFS and OS in patients with HCC undergoing surgery. Preoperative NLR ≥ 2.81 may be a good complementary indicator of poor OS when elevated AFP levels provide no prognostic information. 展开更多
关键词 Blood neutrophil-to-lymphocyte ratio Hepatocellular carcinoma Liver resection Prognosis Postoperative change in neutrophil-to-lymphocyte ratio
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An adaptive backstepping sliding mode method for flight attitude of quadrotor UAVs 被引量:16
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作者 JIANG Xue-ying SU Cheng-li +3 位作者 XU ya-peng LIU Kai SHI Hui-yuan LI Ping 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期616-631,共16页
To overcome nonlinear and 6-DOF(degrees of freedom)under-actuated problems for the attitude and position of quadrotor UAVs,an adaptive backstepping sliding mode method for flight attitude of quadrotor UAVs is proposed... To overcome nonlinear and 6-DOF(degrees of freedom)under-actuated problems for the attitude and position of quadrotor UAVs,an adaptive backstepping sliding mode method for flight attitude of quadrotor UAVs is proposed,in which an adaptive law is designed to online estimate the parameter variations and the upper bound of external disturbances and the assessments is utilized to compensate the backstepping sliding mode control.In addition,the tracking error of the design method is shown to asymptotically converge to zero by using Lyapunov theory.Finally,based on the numerical simulation of quadrotor UAVs using the setting parameters,the results show that the proposed control approach can stabilize the attitude and has hover flight capabilities under the parameter perturbations and external disturbances. 展开更多
关键词 quadrotor UAVs adaptive backstepping sliding mode adaptive law tracking error
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甘肃永靖焦家村上庄2·28滑坡特点及成因分析 被引量:9
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作者 叶伟林 康丽娟 +2 位作者 安亚鹏 吴玮江 孟兴民 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2021年第3期369-375,381,共8页
通过无人机低空航测并结合现场调查,分析焦家村上庄2.28滑坡形态特征,对滑坡诱发因素进行探讨.结果表明,滑坡体积约1.22×10^(5)m^(3),最大滑距为429 m,属于小型黄土滑坡;在滑坡发生前,老滑坡后壁台塬上发育有裂缝和串珠状落水洞,... 通过无人机低空航测并结合现场调查,分析焦家村上庄2.28滑坡形态特征,对滑坡诱发因素进行探讨.结果表明,滑坡体积约1.22×10^(5)m^(3),最大滑距为429 m,属于小型黄土滑坡;在滑坡发生前,老滑坡后壁台塬上发育有裂缝和串珠状落水洞,对滑坡的发生起到促进作用;此次滑坡的主要诱发因子是长期灌溉和冻融作用,长期灌溉尤其是冬灌增加了地下水含量,为冻融作用提供了丰富的水力条件.季节性冻结作用造成地下水溢出带表层土体渗透系数下降,地下水便向排泄口下部凹槽内部逐渐下渗,使凹槽内土体w(水)逐渐增大,土体软化,抗剪强度降低,待气温回暖,季节性冻土开始消融,增大了动水压力,降低了土体的力学性质,引发了滑坡. 展开更多
关键词 黄土滑坡 灌溉 冻融作用 黑方台
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Identifying influential spreaders in complex networks based on entropy weight method and gravity law 被引量:9
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作者 Xiao-Li yan ya-peng Cui Shun-Jiang Ni 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期582-590,共9页
In complex networks,identifying influential spreader is of great significance for improving the reliability of networks and ensuring the safe and effective operation of networks.Nowadays,it is widely used in power net... In complex networks,identifying influential spreader is of great significance for improving the reliability of networks and ensuring the safe and effective operation of networks.Nowadays,it is widely used in power networks,aviation networks,computer networks,and social networks,and so on.Traditional centrality methods mainly include degree centrality,closeness centrality,betweenness centrality,eigenvector centrality,k-shell,etc.However,single centrality method is onesided and inaccurate,and sometimes many nodes have the same centrality value,namely the same ranking result,which makes it difficult to distinguish between nodes.According to several classical methods of identifying influential nodes,in this paper we propose a novel method that is more full-scaled and universally applicable.Taken into account in this method are several aspects of node’s properties,including local topological characteristics,central location of nodes,propagation characteristics,and properties of neighbor nodes.In view of the idea of the multi-attribute decision-making,we regard the basic centrality method as node’s attribute and use the entropy weight method to weigh different attributes,and obtain node’s combined centrality.Then,the combined centrality is applied to the gravity law to comprehensively identify influential nodes in networks.Finally,the classical susceptible-infected-recovered(SIR)model is used to simulate the epidemic spreading in six real-society networks.Our proposed method not only considers the four topological properties of nodes,but also emphasizes the influence of neighbor nodes from the aspect of gravity.It is proved that the new method can effectively overcome the disadvantages of single centrality method and increase the accuracy of identifying influential nodes,which is of great significance for monitoring and controlling the complex networks. 展开更多
关键词 complex networks influential NODES ENTROPY WEIGHT method GRAVITY LAW
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Genome-wide identification and expression analysis of StPP2C gene family in response to multiple stresses in potato (Solanum tuberosum L.) 被引量:8
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作者 WANG Yi-fan LIAO Yu-qiu +3 位作者 WANG ya-peng yaNG Jiang-wei ZHANG Ning SI Huai-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第6期1609-1624,共16页
The plant protein phosphatase 2Cs(PP2Cs)play an essential role in response to stress and abscisic acid(ABA)signaling pathway.However,to date,no systemic characterization of the PP2Cs has yet bee n con ducted in potato... The plant protein phosphatase 2Cs(PP2Cs)play an essential role in response to stress and abscisic acid(ABA)signaling pathway.However,to date,no systemic characterization of the PP2Cs has yet bee n con ducted in potato(Solan um tuberosum L.).In the study,a comprehensive research was performed on genome-wide identification and expression analysis of StPP2C genes in potato.A total of 78 potato StPP2C genes were identified based on specific structure of PP2C domain,which were distributed across 11 out of 12 potato chromosomes and divided into 12(A-L)phylogenetic branches.The result from gene duplication an alysis showed that 14 StPP2Cs were in volved in gene tan dem duplication and 8 genes formed fragment duplicati on eve nts,which indicated that both tandem and fragment duplicati on contributed to the expa nsion of the gene family in evolution.Exon-intron structural analysis showed that they had a wide range of exon numbers.Analysis of protei n con servative motif dem on strated that StPP2Cs contained more similar motif structures in the same phyloge netic branches.The c/s-elements in StPP2C gene promoter regions were mainly responded to light,phytohormone and abiotic stress.Most of them exhibited tissue-specific expressi on patter ns,and some members could differe ntially express un der abiotic stress.The evidenee suggested that StPP2C genes may contribute to different functions in several physiological stress and environmental stress conditi ons.This study could provide new in sights to further in vestigate StPP2C functional characteristics responding to various stresses in potato. 展开更多
关键词 PROTEIN PHOSPHATASE 2C expression pattern stress ABA POTATO
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The Potential Effects and Use of Chinese Herbal Medicine Pine Pollen(Pinus pollen):A Bibliometric Analysis of Pharmacological and Clinical Studies 被引量:8
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作者 Shi-Bing Liang Ning Liang +6 位作者 Fan-Long Bu Bao-Yong Lai ya-peng Zhang Hui-Juan Cao Yu-Tong Fei Nicola Robinson Jian-Ping Liu 《World Journal of Traditional Chinese Medicine》 2020年第2期163-170,共8页
The objectives of this study are to conduct a comprehensive literature search and bibliometric analysis to identify the breadth and volume of pharmacological and clinical studies on pine pollen(Pinus pollen)and to ide... The objectives of this study are to conduct a comprehensive literature search and bibliometric analysis to identify the breadth and volume of pharmacological and clinical studies on pine pollen(Pinus pollen)and to identify the potential effects and the use of pine pollen.Three Chinese electronic databases and two English electronic databases were searched for pharmacological and clinical studies on pine pollen.Data were extracted and analyzed and included publication year,authors,study type,pharmacological research topics or clinical diseases/conditions,usage and type of preparation,authors’conclusions,and adverse effects.Of 239 publications identified,180 were pharmacological studies,37 were clinical trials,and 22 were reviews.Numbers of publications increased particularly from 2004 onward.The top 10 most frequent topics in pharmacological studies were immune regulation,antisenility,antioxidation,liver protection,inhibiting prostate hyperplasia,inhibiting tumor cell proliferation,lowering blood glucose,lowering blood lipids,antifatigue,and improving intestinal function.The top 10 most frequent clinical diseases treated or where pine pollen was used as an adjuvant were bedsores,diaper dermatitis,hyperlipidemia,oral mucositis,eczema,hyperplasia of prostate,hypertension,prostatitis,type 2 diabetes mellitus,and radiodermatitis.Eight trials reported no adverse events associated with pine pollen,one reported mild gastrointestinal reactions,but symptoms disappeared without special management.There have been an increasing number of publications on pine pollen during the past 20 years.Pharmacological studies have shown many potential benefits,and clinical studies have indicated some positive effects when it is either used as a single herb or as an adjuvant to treat disease.Its use as a topical agent,especially for skin diseases,was notable. 展开更多
关键词 Bibliometric analysis Chinese herbal medicine pine pollen Pinus pollen skin disease
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Ventilation control of tunnel drilling dust based on numerical simulation 被引量:8
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作者 JIANG Zhong-an WANG ya-peng MEN Li-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1342-1356,共15页
In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by usi... In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by using FLUENT software,and the numerical simulation analysis of tunnel drilling ventilation and dust removal parameters was carried out.The results show that it is difficult to control the dust pollution of the face by conventional ventilation,and the drilling dust is distributed in the range of 10 m from the face;after the introduction of the long pressure and short suction ventilation scheme,when the ratio of compressed air volume to exhaust air volume is 0.72,the height of the pressure fan is 2.5 m,the distance between the pressure fan and the palm face is 20 m,and the exhaust fan is 12 m away from the palm,the dust concentration control efficiency of the working face is increased by about 60%.Therefore,in the similar long-distance single head tunnel construction,it is appropriate to adopt the dust removal method of long-distance short suction and exhaust fan to ensure the working environment. 展开更多
关键词 dust pollution working environment numerical simulation ventilation parameters
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Preliminary analysis of fuel cycle performance for a small modular heavy water-moderated thorium molten salt reactor 被引量:7
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作者 ya-peng Zhang Yu-Wen Ma +2 位作者 Jian-Hui Wu Jin-Gen Chen Xiang-Zhou Cai 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第11期23-35,共13页
Heavy water-moderated molten salt reactors(HWMSRs)are novel molten salt reactors that adopt heavy water rather than graphite as the moderator while employing liquid fuel.Owing to the high moderating ratio of the heavy... Heavy water-moderated molten salt reactors(HWMSRs)are novel molten salt reactors that adopt heavy water rather than graphite as the moderator while employing liquid fuel.Owing to the high moderating ratio of the heavy water moderator and the utilization of liquid fuel,HWMSRs can achieve a high neutron economy.In this study,a large-scale small modular HWMSR with a thermal power of 500 MWth was proposed and studied.The criticality of the core was evaluated using an in-house critical search calculation code(CSCC),which was developed based on Standardized Computer Analyses for Licensing Evaluation,version 6.1.The preliminary fuel cycle performances(initial conversion ratio(CR),initialfissile fuel loading mass,and temperature coefficient)were investigated by varying the lattice pitch(P)and the molten salt volume fraction(VF).The results demonstrate that the temperature coefficient can be negative over the range of investigated Ps and VFs for both 233U-Th and LEU-Th fuels.A core with a P of 20 cm and a VF of 20%is recommended for 233U-Th and LEU-Th fuels to achieve a high performance of initial CR and fuel loading.Regarding TRU-Th fuel,a core with a smaller P(~5 cm)and larger VF(~24%)is recommended to obtain a negative temperature coefficient. 展开更多
关键词 Molten salt reactor Heavy water-moderated molten salt reactor(HWMSR) Th-U fuel cycle
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Cyclooxygenase-2 expression is associated with initiation of hepatocellular carcinoma, while prostaglandin receptor-1 expression predicts survival 被引量:7
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作者 Hao-Jie yang Jing-Hang Jiang +8 位作者 Yu-ting yang Xiang-Di yang Zhe Guo ya-peng Qi Feng-Hua Zeng Ke-Lan Zhang Neng-Zhi Chen Bang-De Xiang Le-Qun Li 《World Journal of Gastroenterology》 SCIE CAS 2016年第39期8798-8805,共8页
AIM to determine whether cyclooxygenase-2(COX-2) and prostaglandin E1 receptor(EP1) contribute to disease and whether they help predict prognosis.METHODS We retrospectively reviewed the records of 116 patients with he... AIM to determine whether cyclooxygenase-2(COX-2) and prostaglandin E1 receptor(EP1) contribute to disease and whether they help predict prognosis.METHODS We retrospectively reviewed the records of 116 patients with hepatocellular carcinoma(HCC) who underwent surgery between 2008 and 2011 at our hospital. Expression of COX-2 and EP1 receptor was examined by immunohistochemistry of formalin-fixed, paraffinembedded tissues using polyclonal antibodies. Possible associations between immunohistochemical scores and survival were determined.RESULTS Factors associated with poor overall survival(OS) were alpha-fetoprotein > 400 ng/m L, tumor size ≥ 5 cm, and high EP1 receptor expression, but not high COX-2 expression. Disease-free survival was not significantly different between patients with low or high levels of COX-2 or EP1. COX-2 immunoreactivity was significantly higher in well-differentiated HCC tissues(Edmondson grade Ⅰ-Ⅱ) than in poorly differentiated tissues(Edmondson grade Ⅲ-Ⅳ)(P = 0.003). EP1 receptor immunoreactivity was significantly higher in poorly differentiated tissue than in well-differentiated tissue(P = 0.001).CONCLUSION COX-2 expression appears to be linked to early HCC events(initiation), while EP1 receptor expression may participate in tumor progression and predict survival. 展开更多
关键词 CYCLOOXYGENASE-2 Hepatocellular carcinoma Liver resection Prognosis Prostaglandin E1 receptor
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Geomorphic features of Quaternary glaciation in the Taniantaweng Mountain, on the southeastern Qinghai-Tibet Plateau 被引量:5
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作者 ZHANG Wei CHAI Le +5 位作者 IAN S.Evans LIU Liang LI ya-peng QIAO Jing-ru TANG Qian-yu SUN Bo 《Journal of Mountain Science》 SCIE CSCD 2019年第2期256-274,共19页
We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yun... We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yunnan-Guizhou Plateau. To reconstruct the history of glacial evolution during the Quaternary Glaciation, we present a ~13000 km^2 geomorphologic map(1:440,000) for the Quaternary glaciations, as well as three electron spin resonance(ESR) ages and three optically stimulated luminescence(OSL) ages from the landforms. By integrating these with ages from previous studies, four major glacial advances are identified during marine oxygen isotope stages(MIS) 6, 3, 2 and 1. This glacial chronology is in reasonable agreement with existing glacial chronologies from other parts of the Hengduan Mountains and surrounding mountains. Glaciers had extended to the Yuqu River during the glacial maximum advance(MIS 6), but became successively more restricted from MIS 3 to MIS 1. The glacial distribution show that precipitation brought by the south Asian monsoon might play a primary role in driving glacial advances during the last glacial period in the southeastern Qinghai-Tibet Plateau. 展开更多
关键词 Qinghai-Tibet Plateau Taniantaweng MOUNTAIN GLACIAL LANDFORM ESR DATING OSL DATING South Asian monsoon
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An algorithm to resolve γ-rays from charged cosmic rays with DAMPE 被引量:4
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作者 Zun-Lei Xu Kai-Kai Duan +18 位作者 Zhao-Qiang Shen Shi-Jun Lei Tie-Kuang Dong Fabio Gargano Simone Garrappa Dong-ya Guo Wei Jiang Xiang Li Yun-Feng Liang Mario Nicola Mazziotta Maria Fernanda Munoz Salinas Meng Su Valerio Vagelli Qiang Yuan Chuan Yue Jing-Jing Zang ya-peng Zhang Yun-Long Zhang Stephan Zimmer 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第3期25-36,共12页
The DArk Matter Particle Explorer(DAMPE),also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne observatory.One of the main scientific goals o... The DArk Matter Particle Explorer(DAMPE),also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne observatory.One of the main scientific goals of DAMPE is to observe Ge V-Te V high energy γ-rays with accurate energy,angular and time resolution,to indirectly search for dark matter particles and for the study of high energy astrophysics. Due to the comparatively higher fluxes of charged cosmic rays with respect to γ-rays,it is challenging to identify γ-rays with sufficiently high efficiency,minimizing the amount of charged cosmic ray contamination. In this work we present a method to identify γ-rays in DAMPE data based on Monte Carlo simulations,using the powerful electromagnetic/hadronic shower discrimination provided by the calorimeter and the veto detection of charged particles provided by the plastic scintillation detector. Monte Carlo simulations show that after this selection the number of electrons and protons that contaminate the selected γ-ray events at~10 Ge V amounts to less than 1% of the selected sample.Finally,we use flight data to verify the effectiveness of the method by highlighting known γ-ray sources in the sky and by reconstructing preliminary light curves of the Geminga pulsar. 展开更多
关键词 gamma rays general - instrumentation detectors - methods data analysis
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MD simulation of a copper rod under thermal shock 被引量:4
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作者 Rong-Hou Xia Xiao-Geng Tian ya-peng Shen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期599-604,共6页
In this paper, thermoelastic problem of onedimensional copper rod under thermal shock is simulated using molecular dynamics method by adopting embedded atom method potential. The rod is on axis x, the left outermost s... In this paper, thermoelastic problem of onedimensional copper rod under thermal shock is simulated using molecular dynamics method by adopting embedded atom method potential. The rod is on axis x, the left outermost surface of which is traction free and the right outermost surface is fixed. Free boundary condition is imposed on the outermost surfaces in direction y and z. The left and right ends of the rod are subjected to hot and cold baths, respectively. Temperature, displacement and stress distributions are obtained along the rod at different moments, which are shown to be limited in the mobile region, indicating that the heat propagation speed is limited rather than infinite. This is consistent with the prediction given by generalized thermoelastic theory. From simulation results we find that the speed of heat conduction is the same as the speed of thermal stress wave. In the present paper, the simulations are conducted using the large-scale atomic/molecular massively parallel simulator and completed visualization software. 展开更多
关键词 Embedded atom method potential Molecular dynamics simulation Thermoelastic coupling Thermal stress
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