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The spin delocalization substituent parameter σ——8. The spin-delocalizing abilities of the nitro, cyano, carbomethoxy, carboxy and carbamyl groups

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Chinese Journal of Chemistry 1991年第6期9卷 521-526页

作者： JI, Guo-Zhen JIANG, Xi-Kui shi, wen-Ting. Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, Shanghai 200032 Shanghai Institute of Organic Chemistry The Chinese Academy of Sciences Shanghai 200032

The rate constants (k) of the homo-cycloaddition reactions of five substituted α, β, β-tri- fluorostyrenes (TFS’s), i.e. p-nitrotrifluorostyrene (4), p-cyanotrifluorostyrene (5), p-carbomethoxytri- fluorostyrene (6), p-carboxytrifluorostyrene (7) and p-carbamyltrifluorostyrene (8), have been measured in the temperature range of 110-160℃. The ~σmb polar substituent parameters of these TFS's cal- culated from ^(19) F NMR chemical shifts are: NO_2, 0.86; CN, 0.86; CO_2CH_2, 0.40; CO_2H, 0.31; CONH_2, 0.10. The spin delocalization substituent parameters ~σT of NO_2, CN, CO_2 CH_2, CO_2H and CONH_2 are 0.32, 0.38, 0.31, 0.37 and 0.37 respectively. Thus all these electron-pair attracting groups are also very effective spin-stabilizers.

关键词： The spin delocalization substituent parameter carboxy and carbamyl groups cyano

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基于3-TPS混联机床的后置处理算法

东北大学学报（自然科学版） 2005年第10期26卷 998-1001页

作者：石宏赵亮蔡光起东北大学机械工程与自动化学院辽宁沈阳110004

介绍了一种新型立卧转换式三杆混联机床3-TPS(RRR)混联机床,对该机床的结构进行了分析.该机床具有工作空间大、立卧转换、五轴联动、五面加工等特点,并具有加工中心的功能.给出了该机床在实现三轴、四轴加工时的坐标变换过程及变换方程... 详细信息

介绍了一种新型立卧转换式三杆混联机床3-TPS(RRR)混联机床,对该机床的结构进行了分析.该机床具有工作空间大、立卧转换、五轴联动、五面加工等特点,并具有加工中心的功能.给出了该机床在实现三轴、四轴加工时的坐标变换过程及变换方程,给出了实现三轴、四轴加工时的后置处理算法及数学模型,并对该机床的立式加工和卧式加工两种情况进行了分析,给出了算法和显式方程.

关键词：混联机床机构后置处理算法立卧转换

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自动检票系统设计及其实现

中国铁道科学 2005年第5期26卷 112-118页

作者：王国光史天运铁道科学研究院电子计算技术研究所北京100081

概述国内外自动检票系统的发展现状,提出按地区中心计算机系统—车站计算机系统—自动检票机三层体系结构构建中国铁路的自动检票系统,论述各子系统的功能划分和软件模块的构成与设计。提出:采用纸质磁卡票作为单程票,非接触IC卡票作为... 详细信息

概述国内外自动检票系统的发展现状,提出按地区中心计算机系统—车站计算机系统—自动检票机三层体系结构构建中国铁路的自动检票系统,论述各子系统的功能划分和软件模块的构成与设计。提出:采用纸质磁卡票作为单程票,非接触IC卡票作为储值票;采用对称和非对称加密方法实现设备间的身份认证和通信数据的加密,以保证自动检票机与车站服务器之间通信的安全;采用嵌入式实时操作系统来保证自动检票机的实时性和可靠性;采用基于优先级的抢占式任务调度方式处理自动检票机软件各任务间的关系,检票交易数据的处理时机与数据量因子和时间间隔因子相关。

关键词：自动检票系统自动检票机嵌入式实时操作系统任务调度

Human ribonuclease 9,a member of ribonuclease A superfamily,specifically expressed in epididymis,is a novel sperm-binding protein

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Asian Journal of Andrology 2009年第2期11卷 240-251页

作者： Gui-Zhi Cheng Jian-Yuan Li Fang Li Hai-Yan Wang guang-Xia shi Department of Immunology Dalian Medical UniversityDalian 116044China Research Center Yuhuangding HospitalYantai 264000China

To explore the functions of human ribonuclease 9(RNase 9),we constructed a mammalian fusion expression vector pcDNA-hRNase9,prepared recombinant human RNase 9-His fusion protein from HEK293T cells and determined its N-terminal amino acid *** to the determined mature protein,recombinant human RNase 9 was prepared in *** activity and antibacterial activity of recombinant human RNase 9 were detected,and the distribution of human RNase 9 on tissues and ejaculated spermatozoa and in vitro capacitated spermatozoa were analyzed via indirect immunofluorescence *** results showed that recombinant human RNase 9 did not exhibit detectable ribonucleolytic activity against yeast tRNA,but exhibited antibacterial activity,in a concentration/time dependent manner,against *** analyses showed that the predicted human RNase 9 was present throughout the epididymis,but not present in other tissues examined,and human RNase 9 was also present on the entire head and neck regions of human ejaculated spermatozoa and in vitro capacitated *** results suggest that human RNase 9 may play roles in host defense of male reproductive tract.

关键词： ribonuclease A superfamily epididymis epididymal secretory proteins spermatozoa sperm maturation male reproductive tract host defense

Association of serum uric acid with different levels of glucose and related factors

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Chinese Medical Journal 2011年第10期124卷 1443-1448页

作者： YUAN Hui-juan YANG Xu-guang shi Xiao-yang TIAN Rui ZHAO Zhi-gang Department of Endocrinology Henan Provincial People's Hospital Zhengzhou Henan 450003 China Department of Endocrinology People's Hospital of ZhengzhouCity Zhengzhou Henan 450053 China

Background Previous studies have demonstrated that serum uric acid （UA） is an independent predictor of incident type 2 diabetes mellitus （T2DM） in general populations. This study aimed to investigate specific characteristics of UA and its relationship between UA and blood glucose and other risk factors in the Chinese *** A total of 946 subjects were included in this study. UA, glucose, insulin, fractional excretion of UA （FEua）,creatinine clearance rate （Ccr）, hemoglobin A1c （HbA1c）, fructosamine （FA）, blood pressure and lipids were studied and also reexamined after the patients underwent two weeks of combined *** UA levels were the highest in subjects with impaired glucose regulation （IGR）, followed by subjects with normoglycemia （NGT） and finally by subjects with T2DM. The level of the 2-hour postprandial insulin and the area under the curve for insulin （AUCins） showed a similar tendency. The UA levels initially increased with increasing fasting blood glucose （FBG） and postprandial blood glucose （PPBG） levels, up to 7 mmol/L and 10 mmol/L, respectively, and thereafter decreased at higher FBG and PPBG levels. Compared with subjects in the lower serum UA quartile, subjects in the upper quartile of serum UA levels had higher weights, triglyceride levels, and creatinine levels as well as lower Ccr and FEua levels. Compared with women＇s group, UA levels were higher, and FEua levels were lower in men＇s group. Sex,body mass index （BMI）, mean arterial blood pressure （MAP）, serum triglycerides （TG）, FA and Ccr were independent correlation factors of UA. UA decreased and FEua increased after the patients underwent a combined *** UA increased initially and then decreased as glucose levels increased from NGT to IGR and *** with NGT and T2DM, IGR subjects had higher SUA levels, which related to its high levels of insulin. Under T2DM, male gender, BMI, MAP, Ccr, TG and FA are independent correlation factors of UA. Gluc

关键词： diabetes mellitus serum uric acid blood glucose fractional excretion of uric acid insulin

PM_(2.5)有机提取物经由铁死亡诱导人支气管上皮细胞损伤的研究

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环境卫生学杂志 2024年第4期14卷 303-311,361页

作者：王盟盟龙玥含陈圆圆顾雯王超石莹唐宋段链中国疾病预防控制中心环境与人群健康重点实验室/中国疾病预防控制中心环境与健康相关产品安全所北京100021 南京医科大学全球健康中心

目的探讨细颗粒物(PM_(2.5))有机提取物能否诱导人支气管上皮细胞铁死亡。方法通过索氏提取法提取PM_(2.5)中有机物作为受试物,使用BEAS-2B细胞,以0.1%DMSO溶液作为溶剂对照,染毒于不同剂量(2.5、5、10和20μg/mL)的PM_(2.5)有机提取物... 详细信息

目的探讨细颗粒物(PM_(2.5))有机提取物能否诱导人支气管上皮细胞铁死亡。方法通过索氏提取法提取PM_(2.5)中有机物作为受试物,使用BEAS-2B细胞,以0.1%DMSO溶液作为溶剂对照,染毒于不同剂量(2.5、5、10和20μg/mL)的PM_(2.5)有机提取物构建细胞染毒模型;使用铁死亡抑制剂(Ferrostatin-1,Fer-1)构建铁死亡干预模型。通过吸光度法检测PM_(2.5)有机提取物染毒后BEAS-2B细胞存活率、丙二醛(malondialdehyde,MDA)和谷胱甘肽(glutathione,GSH)浓度;通过荧光法检测细胞内Fe2+含量、活性氧(reactive oxygen species,ROS)含量和脂质过氧化物(lipid peroxidation,LPO)含量;通过qRT-PCR方法检测铁死亡相关基因(如GPX4、SLC7A11、ACSL4、FTL和TFRC等)表达。结果与对照组相比,PM_(2.5)有机提取物染毒24 h后,当染毒剂量为10μg/mL时,细胞内Fe2+含量、ROS含量、LPO含量和MDA浓度均出现显著上升;而GSH浓度出现显著下降;qRT-PCR结果显示,细胞暴露于20μg/mL PM_(2.5)有机提取物时,细胞内铁死亡相关基因GPX4显著下调,SLC7A11、ACSL4、FTL和TFRC出现显著性上调。干预实验中,使用铁死亡特异性抑制剂Fer-1干预后上述变化得到明显改善。结论PM_(2.5)有机提取物可能通过诱导细胞铁死亡导致呼吸系统细胞损伤,进而对肺组织产生潜在健康影响。

关键词：细颗粒物(PM_(2.5)) 有机提取物铁死亡人支气管上皮细胞肺损伤

急性肾损伤向慢性肾脏病转化的肾脏脂质代谢特征

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临床肾脏病杂志 2024年第6期24卷 484-493页

作者：陈颖雯王伟腾李路安施清瀛骆洁仪梁馨苓华南理工大学医学院广州510006 南方医科大学附属广东省人民医院(广东省医学科学院) 广州510080 南方医科大学第二临床学院广州510515 广东省心血管病研究所广州510080

目的探讨急性肾损伤(acute kidney injury,AKI)向慢性肾脏病(chronic kidney disease,CKD)转化中肾组织脂质代谢特征。方法通过肾脏缺血再灌注损伤(ischemia-reperfusion injury,IRI)(双侧肾动脉夹闭30 min)构建AKI向CKD转化的小鼠模型。取第2天、第14天及第28天小鼠肾脏组织,通过超高效液相色谱串联质谱检测不同时间点IRI小鼠与假手术组小鼠肾脏脂质代谢,分析各组间脂质代谢差异,通过京都基因和基因组百科全书富集化分析揭示AKI向CKD转化脂质代谢所参与的重要通路。结果 IRI小鼠第2天血肌酐较假手术组明显升高,并伴有肾小管明显急性损伤;在第14天和28天时,IRI小鼠肾脏纤维化程度明显加重。我们总共检测到1715种脂质代谢物。代谢物主要成分分析显示,不仅IRI小鼠在各个时间点均与假手术组显示出不同脂质代谢特征,而且IRI小鼠不同时间点间的脂质代谢也存在较大差异。在AKI阶段,肾脏脂质代谢特征以中性脂质蓄积最为明显,而在IRI后14 d和28 d时,改变最明显的脂质代谢物为甘油磷脂及鞘脂。在IRI 28 d时,下调甘油磷脂(186种)种类多于上调甘油磷脂(132种)。在上调甘油磷脂中,烯基(乙烯基)醚-磷脂酰乙醇胺最为明显,而在下调磷脂中,磷脂酰甘油最为明显。京都基因和基因组百科全书富集化分析显示,在此阶段甘油磷脂代谢通路下调最为显著。结论我们的研究显示,AKI向CKD转化整个过程中,肾脏脂质代谢发生了显著变化,并且急性期与慢性期的脂质组学同样存在明显差异。甘油磷脂,尤其是烯基(乙烯基)醚-磷脂酰乙醇胺下调、磷脂酰甘油上调可能在AKI向CKD转化后期肾脏纤维化中发挥了重要作用。我们的研究为未来研究脂质代谢在AKI向CKD转化中的作用与机制提供了基础。

关键词：脂质组学超高效液相色谱串联质谱急性肾损伤慢性肾脏病甘油磷脂

A Preliminary Study on Traditional Level-trench Method to Prevent Rill Initiation in the Three Gorges Region,China

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Journal of Mountain Science 2011年第6期8卷 876-881页

作者： YAN Dongchun wen Anbang HE Xiubin shi Zhonglin XIONG Donghong LONG Yi Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan 610041 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The level-trench method is a traditional tillage operation to develop a drainage system on slope land in the Three Gorges region. Before crops are planted, farmers prepare the land with level trenches spaced 3-1o m apart, depending on the slope gradient： steeper slopes require shorter distances. Little scientific analysis has been done on the use of traditional level trenches for soil conservation. We conducted a field investigation and simulation experiments, and present a comparison between the spacing of level trenches and the slope length required for rill initiation. The results indicate that the spacing of level trenches in farmland is close to the slope length required for rill initiation in the experimental plots, and regression models of trench spacing with the gradient and the slope length required for rill initiation with the gradient have similar formats; the coefficients of determination （R2） for the two equations are 0.99 and 0.88, respectively. There were some differences between the field survey and experiments, but we conclude that the traditional level-trench method has an important role in preventing rill initiation.

关键词： Level trench Rill Initiation Purple Soil Three Gorges Region

INDEPTH Ⅳ深反射地震揭示的东昆仑造山带隆升过程

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地球物理学报 2016年第9期59卷 3211-3222页

作者：刘志伟赵文津吴珍汉史大年宋洋邓世广中国地质科学院北京100037 中国地质科学院矿产资源研究所北京100037

INDEPTH Ⅳ深反射地震数据处理的重点和难点是近地表风化壳静校正和异常振幅噪音衰减,通过初至波剩余折射静校正技术、异常振幅噪声衰减技术和CRS优化叠加技术获得了信噪比较高的地震剖面.由INDEPTH Ⅳ深反射地震剖面揭示,东昆仑造山带... 详细信息

INDEPTH Ⅳ深反射地震数据处理的重点和难点是近地表风化壳静校正和异常振幅噪音衰减,通过初至波剩余折射静校正技术、异常振幅噪声衰减技术和CRS优化叠加技术获得了信噪比较高的地震剖面.由INDEPTH Ⅳ深反射地震剖面揭示,东昆仑造山带上地壳地层具有挤压走滑、断展褶皱等动力学特点,岩石圈上、下地壳之间存在不连续的松潘—甘孜古洋壳反射特征,东昆仑山下偏南局部Moho面以上低频异常反射特征指示局部熔融、低速高导体存在.综合INDEPTH Ⅳ深反射地震剖面和其他地球物理数据分析认为,东昆仑造山带隆升过程非常复杂,隆升过程至少经过两次主期变形,一期是中生代三叠纪松潘—甘孜洋向北俯冲引发被动大陆边缘造山,另一期是新生代古近纪印度—欧亚板块碰撞致使羌塘地块北移造成的上地壳挤压隆升.利用INDEPTH Ⅳ深反射地震单炮、速度和叠加剖面等成果,综合解译数据,最终提出东昆仑造山带隆升过程的另一种模式,以有助于深化对东昆仑造山模式的认识.

关键词：深反射地震东昆仑造山带松潘—甘孜洋壳 INDEPTH Ⅳ