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Room-temperature-densified H_(3)BO_(3) microwave dielectric ceramics with ultra-low permittivity and ultra-high Qf value

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Journal of Materiomics 2020年第2期6卷 233-239页

作者： wen bin hong Lei Li Han Yan Shu Ya Wu Hang Sheng Yang Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China

With the rapid development of mobile communication technology towards 5G and 6G,the microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are urgently ***,the excellent microwave dielectric properties are reported in H3BO3 ceramics with the molecular crystal structure,whose permittivity(2.84)and density(1.46 g/cm^(3))are record-low among the low-loss *** ultra-high Qf value of 146,000 GHz(or the ultra-low dielectric loss of 1.03×10^(-4) at 15 GHz)is also ***,the H_(3)BO_(3) ceramics can be densified at room temperature by a simple cold sintering process in a short time of 10 min,and this brings many advantages for the integration with microwave *** large molecule volume originating from the molecular crystal structure and the low dielectric polarizabilities of H^(+) and B^(3+) are responsible for the ultra-low permittivity of H_(3)BO_(3) ceramics,and more microwave dielectric materials with ultra-low permittivity and ultra-high Qf value are expected to be explored in the molecular crystals.

关键词： Boric acid Microwave dielectric ceramics Room-temperature cold sintering Ultra-low permittivity

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轻度认知障碍患者的脑血流变化

中国临床康复 2005年第37期9卷 6-7页

作者：闻红斌周宏斌华中科技大学同济医学院附属襄樊医院神经内科湖北省襄樊市441021

目的:探讨经颅多普勒超声对轻度认知障碍患者的诊断价值。方法:选择2003-03/2004-10华中科技大学同济医学院附属襄樊医院收治的30例轻度认知障碍患者,以32例健康人为正常对照组。所有被试者行经颅多普勒超声检查,观察双侧大脑中动脉,大... 详细信息

目的:探讨经颅多普勒超声对轻度认知障碍患者的诊断价值。方法:选择2003-03/2004-10华中科技大学同济医学院附属襄樊医院收治的30例轻度认知障碍患者,以32例健康人为正常对照组。所有被试者行经颅多普勒超声检查,观察双侧大脑中动脉,大脑前动脉,大脑后动脉,双侧椎动脉,基底动脉血流速度;还进行神经心理学检测(包括简明精神状态评定量表,总体衰退量表和日常生活活动能力量表)。结果:按意向处理分析,62例被试者全部进入结果分析。①轻度认知障碍患者经颅多普勒超声异常情况:异常率为91﹪,其中颈内动脉系统异常率为56﹪,椎基底动脉系统异常率为52﹪。脑血流双侧下降18例,单侧下降8例,两侧不对称7例。②脑血流速度:轻度认知障碍患者大脑中动脉和基底动脉低于正常对照组[(43.6±8.9),(58.7±9.9)cm/s;(28.6±5.1),(38.7±8.1)cm/s,P<0.05]。③两者神经心理学评分无明显差异。结论:①轻度认知障碍患者已出现局部脑血流的下降,但并非全脑血流下降。②经颅多普勒超声对于轻度认知障碍患者的病因学研究及早期诊断及干预具有积极意义。

关键词：认知障碍血流速度超声检查,多普勒,经颅

Myxoid adrenocortical adenoma： a case report

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Chinese Medical Journal 2008年第16期121卷 1598-1600页

作者： ZHU Yu WU Yu-xuan ZHANG Chong-yu ZHAO Ju-ping RUI wen-bin HE hong-chao SHEN Zhou-jun Department of Urology Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200025 China

Myxoid adrenocortical adenomas are extremely rare .with only 24 cases reported, The first case wasreported by Tang et al in 1979 which was diagnosed as a myxoid adrenocortical carcinoma. Nearly all the reports were of single case except Brown et al who described a group of 14 cases. We report here an additional case of myxoid adrenocortical adenoma with an immunohistochemical study of the tumor and discuss the diagnosis with reference to the current literature.

关键词： myxoid adrenocortical tumor myxoid adrenocortical adenoma immunohistochemistry

C反应蛋白、糖化血红蛋白与糖尿病肾病的相关性研究

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中国医药导刊 2010年第1期12卷 101-102页

作者：温滨红沈阳市红十字会医院内分泌科沈阳110013

目的:探讨血清C反应蛋白(CRP)等指标与糖尿病肾病(DN)的关系。方法:研究对象为152例2型糖尿病患者,其中63例诊断糖尿病肾病。测量并记录身高、体重、血压,测定血清CRP、尿微量白蛋白(UMA)、同步尿肌酐(Ucr)、糖化血红蛋白(HbA1c)、甘油... 详细信息

目的:探讨血清C反应蛋白(CRP)等指标与糖尿病肾病(DN)的关系。方法:研究对象为152例2型糖尿病患者,其中63例诊断糖尿病肾病。测量并记录身高、体重、血压,测定血清CRP、尿微量白蛋白(UMA)、同步尿肌酐(Ucr)、糖化血红蛋白(HbA1c)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)。结果:按UMA/Ucr比率(ACR)分成正常、微量白蛋白尿、大量蛋白尿组,大量白蛋白尿患者年龄更大、病程更长,并且CRP、HbA1c、TG水平显著升高。逐步回归分析显示年龄、病程、CRP、HbAlc与ACR呈正相关关系,共同决定了ACR 34%的变化。结论:CRP、HbA1c作为危险因子与糖尿病肾病密切相关。

关键词：糖尿病肾病 C反应蛋白糖化血红蛋白

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血清镁水平与代谢综合征的关系

中国误诊学杂志 2010年第9期10卷 2039-2040页

作者：温滨红辽宁省沈阳市红十字会医院 110013

目的:探讨血清镁离子浓度与代谢综合征(MS)的关系。方法:对MS患者和正常对照各96例进行比较分析。结果:MS组的低镁血症患病率显著高于正常对照组(P=0.000),MS组的血清镁水平显著低于正常对照组(P=0.000)。低血镁症与MS、血脂异常、高血... 详细信息

目的:探讨血清镁离子浓度与代谢综合征(MS)的关系。方法:对MS患者和正常对照各96例进行比较分析。结果:MS组的低镁血症患病率显著高于正常对照组(P=0.000),MS组的血清镁水平显著低于正常对照组(P=0.000)。低血镁症与MS、血脂异常、高血糖的患病独立相关,而与肥胖症、高血压患病无相关性。结论:MS患者中存在血清镁水平下降的现象,而且这一现象与MS、血脂异常、高血糖的患病独立相关。

关键词：代谢综合征X/血液镁/血液

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan Shi bin hong Xiaoying Bian wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

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高速客车轻量化车体耐碰撞结构的优化设计

同济大学学报（自然科学版） 2004年第11期32卷 1499-1503页

作者：王文斌赵洪伦同济大学沪西校区机车车辆研究所上海200331

提出了基于最轻量优化的高速客车车体耐碰撞结构设计策略 ,通过多层优化技术 ,满足在常规载荷工况下结构处于弹性状态 ,在碰撞载荷工况下局部预定部位发生塑性大变形 ,而客室的主体结构仍处于弹性状态 ,从而实现耐撞击车体结构轻量化设... 详细信息

提出了基于最轻量优化的高速客车车体耐碰撞结构设计策略 ,通过多层优化技术 ,满足在常规载荷工况下结构处于弹性状态 ,在碰撞载荷工况下局部预定部位发生塑性大变形 ,而客室的主体结构仍处于弹性状态 ,从而实现耐撞击车体结构轻量化设计的目标 .运用线性和非线性有限元技术以车体概念模型和高速客车实车为例进行了优化设计 ,证实了优化设计策略的可行性和有效性 .

关键词：高速列车铁道车辆耐碰撞轻量化优化

Impact of depressed left ventricular function on outcomes in patients with three-vessel coronary disease undergoing percutaneous coronary intervention

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Chinese Medical Journal 2013年第4期126卷 609-614页

作者： GAO Zhan XU Bo Ajay J. Kirtane YANG Yue-jin YUAN Jin-qing CHEN Ji-lin QIAO Shu-bin WU Yong-jian QIN Xue-wen YAN hong-bin YAO Min LIU Hai-bo CHEN Jue YOU Shi-jie GAO Run-lin Cardiovascular Institute & Fu Wai Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing100037 China

Background Patients with multivessel coronary artery disease and depressed left ventricular ejection fraction （LVEF） represent a high risk group of patients for coronary revascularization. There are limited data on percutaneous coronary intervention treatment in this population. Methods Among a cohort of 4335 patients with three-vessel disease with or without left main disease undergoing percutaneous coronary intervention, 191 patients had LVEF 〈40% （low ejection fraction （EF）） and 4144 patients had LVEF _〉40%. In-hospital and long-term outcomes were examined according to LVEF. Results The estimated two-year rates of major adverse cardiac events, cardiac death, and myocardial infarction were significantly higher in the low EF group （19.64% vs. 8.73%, Log-rank test： P 〈0.01; 10.30% vs. 1.33%, Log-rank test： P 〈0.01, and 10.32% vs. 2.28%, Log-rank test： P 〈0.01 respectively）, but there was no difference in the rates of target vessel revascularization （6.18% vs. 6.11%, Log-rank test： P=0.96）. Using the Cox proportional hazard models, LVEF 〈40% was a significant risk factor for cardiac death, myocardial infarction, and major adverse cardiac events （OR （95% CI）： 4.779 （2.369-9.637）, 2.673 （1.353-5.282）, and 1.827 （1.187-2.813） respectively）, but was not a statistically significant risk factor for target vessel revascularization （OR （95% CI）： 1.094 （0.558-2.147））. Conclusion Among patients undergoing percutaneous coronary intervention for multivessel coronary artery disease, left ventricular dysfunction remains associated with further risk of cardiac death in-hospital and during long-term follow-up.

关键词： three-vessel coronary disease left ventricular dysfunction percutaneous coronary intervention

基于Visiual ***框架的移动自组网安全架构设计与实现

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桂林电子科技大学学报 2007年第5期27卷 357-361页

作者：文彬宏广西科技信息网络中心广西南宁530012

移动自组网具有动态的拓扑结构,缺乏固定的基础设施,并且所使用的设备在处理器性能和电池寿命等方面都受到了限制,从而对网络安全构成挑战。通过对移动自组网和计算机安全领域进行深入研究,给出了移动自组网中的安全漏洞和攻击,提出一... 详细信息

移动自组网具有动态的拓扑结构,缺乏固定的基础设施,并且所使用的设备在处理器性能和电池寿命等方面都受到了限制,从而对网络安全构成挑战。通过对移动自组网和计算机安全领域进行深入研究,给出了移动自组网中的安全漏洞和攻击,提出一种创建和管理安全的移动自组网的方案。方案的目标是提供一个能够在PDA上实现并适用于办公环境的框架。基于提出的安全组网方案、策略和Visiual ***框架,示例创建了PDA办公环境下的用于会议临时使用或支持项目组长期工作的移动自组网系统功能开发模块与使用说明。

关键词：移动自组网安全架构 PDA