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热塑性变形对Mg-Zn-Zr-Ce合金组织与性能的影响

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中国有色金属学报 2018年第3期28卷 502-508页

作者：雷少帆文九巴贺俊光刘亚河南科技大学材料科学与工程学院洛阳471023 有色金属共性技术河南省协同创新中心洛阳471023

利用光学显微镜、扫描电子显微镜、透射电子显微镜、失重测试、电化学测试与拉伸试验研究热挤压与退火温度对Mg-Zn-Zr-Ce生物镁合金组织与性能的影响。结果表明:热塑性变形后合金发生动态再结晶,合金的组织由细小的再结晶晶粒与未再结... 详细信息

利用光学显微镜、扫描电子显微镜、透射电子显微镜、失重测试、电化学测试与拉伸试验研究热挤压与退火温度对Mg-Zn-Zr-Ce生物镁合金组织与性能的影响。结果表明:热塑性变形后合金发生动态再结晶,合金的组织由细小的再结晶晶粒与未再结晶的晶粒组成;退火后变形晶粒发生再结晶,随着退火温度的升高,晶粒逐渐长大。当退火温度高于200℃时,合金的腐蚀电流密度(Jcorr)与平均晶粒尺寸(d)满足Jcorr=a+bd^(-1/2)方程。由该方程可推测出经200℃退火3h后,合金的腐蚀电流密度最低,合金的综合性能最好,抗拉强度与伸长率分别达到245.8MPa和16.2%,腐蚀速率为0.7235mm/a。

关键词：生物镁合金细晶强化耐蚀性力学性能

Association of IL-7 with disease progression in Chinese HIV-1 seropositive individuals

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Chinese Medical Journal 2006年第4期119卷 288-293页

作者： WANg Qi SHANg Hong WANg ya-nan JIANg Yong-jun LIU Jing ZHANg Zi-ning AIDS Research Center First Affiliated Hospital China Medical University Shenyang 110001 China

ba.kground Elevated levels of interleukin-7 （IL-7） have been correlated with CD4^＋ T cell depletion and the emergence of syncytium-inducing （SI） variants in human immunodeficiency virus type-1 （HIV-1） infection, and suggested as an indicator of acquired immunodeficiency syndrome （AIDS） disease progression. Therefore, we investigated the effects of IL-7 on disease progression and virus phenotype in Chinese HIV/AIDS patients. Methods In a cross-sectional study of 71 untreated HIV-1 seropositive individuals and 12 healthy donors, plasma IL-7 levels were determined by an ultra sensitive enzyme-linked immunosorbent assay （ELISA）, and its relations to CD4^＋ T cells, CD8^＋ T cells, plasma viral loads and HIV phenotypes were analyzed. Results Significant higher IL-7 levels were found in Chinese HIV/AIDS patients [（3.33±3.60） pg/ml] than those of health controls [（1.2±0.81） pg/ml] （P〈0.05）, and IL-7 levels were inversely associated with CD4^＋ T cell counts （r=-0.497, P〈0.01）. Furthermore, IL-7 levels were significant higher in patients with SI variants [（9.12±4.55） pg/ml] than those with non-syncytium-inducing variants [（1.50±2.69） pg/ml] （P〈0.01）. Conclusions Increased IL-7 levels were found in Chinese HIV/AIDS patients and significantly associated with disease progression, thus increased IL-7 plasma levels may indicate disease progression.

关键词： human immunodeficiency virus 1 acquired immunodeficiency syndrome interleukin-7 cytokines Chinese

Cost-effectiveness of diagnostic approaches to vasovagal syncope in children and adolescents in China： a health economic analysis

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Chinese Medical Journal 2010年第19期123卷 2635-2639页

作者： LI ya-wen CHEN Li DU Jun-ba. ya.g Yuan-yun JIN Hong-fang School of Economics and Management Beijing University of Posts and Telecommunications Beijing 102209 China Department of Pediatrics Peking University First Hospital Beijing 100034 China School of Nursing Peking University Health Science Center Beijing 100191 China

ba.kground Syncope is a common clinical problem with multiple causes. Vasovagal syncope （VVS） is by far the most frequent cause of syncope in children and adolescents. The traditional diagnostic approach to VVS of children and adolescents is ba.ed on a series of tests to exclude all other causes, which is complex and time and medical resource consuming. Attempts have been made to develop a new cost-effective diagnostic approach to avoid these problems. This study aimed to compare the economic effectiveness and diagnostic value of the traditional diagnostic approach to VVS of children with a new diagnostic approach. Methods One hundred and eighteen children diagnosed as VVS were divided into two groups according to the different diagnostic approaches. The diagnostic value of the two diagnostic approaches was then analyzed. Meanwhile, the costs of hospitalization, diagnostic testing and hospital stay were determined. Data were evaluated by the cost-minimization analysis. Results The diagnostic value of the new diagnostic approach was similar to that of the traditional diagnostic approach （56.57% vs. 53.91%, P=0.697）. However, the cost of hospitalization per patient by the new diagnostic approach was （1507.08±144.63） Yuan （RMB） which was less than that of the traditional diagnostic approach （2603.64±2.08.19） Yuan. The costs of diagnostic tests per patient by the new diagnostic approach was （1256.04±109.14） Yuan and by the traditional approach （2175.22±153.32） Yuan. Conclusion Compared to the traditional diagnostic approach to diagnose VVS in children and adolescents, the new diagnostic approach is of a good economic value, and it should be popularized in clinical practice.

关键词： vasovagal syncope diagnosis economics children

常规器械经脐单孔腹腔镜胆囊切除术治疗急性胆囊炎患者的疗效

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医疗装备 2017年第23期30卷 5-6页

作者：巴雅尔上海市奉贤区奉城医院普通外科上海201411

目的比较常规器械经脐单孔腹腔镜与传统腹腔镜胆囊切除术治疗急性胆囊炎患者的疗效。方法选取2016年4月至2017年4月收治的发病病程在72 h内的急性胆囊炎患者60例,完全随机分为试验组和对照组,各30例。试验组行常规器械经脐单孔腹腔镜胆... 详细信息

目的比较常规器械经脐单孔腹腔镜与传统腹腔镜胆囊切除术治疗急性胆囊炎患者的疗效。方法选取2016年4月至2017年4月收治的发病病程在72 h内的急性胆囊炎患者60例,完全随机分为试验组和对照组,各30例。试验组行常规器械经脐单孔腹腔镜胆囊切除术,对照组行传统腹腔镜切除术,比较两组手术时间、术中出血量、术后并发症发生率、术后疼痛情况、手术费用和切口美观效果。结果试验组手术费用,住院时间,术后第1,2,3天疼痛评分以及并发症发生率均低于对照组,切口美观满意度高于对照组,差异均有统计学意义(P0.05)。结论常规器械经脐单孔腹腔镜胆囊切除术治疗急性胆囊炎具有创伤小、切口瘢痕小、美观、术后疼痛低等特点,且并发症少,安全可行。

关键词：单孔腹腔镜胆囊切除术急性胆囊炎

挤压温度对Mg-2.0Zn-0.5Zr-3.0gd生物降解镁合金组织、力学性能及耐腐蚀性能的影响

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中国有色金属学报 2018年第12期28卷 2422-2432页

作者：姚怀文九巴熊毅贺俊光刘亚河南科技大学材料科学与工程学院洛阳471023 有色金属共性技术河南省协同创新中心洛阳471023

研究挤压温度对铸态Mg-2.0Zn-0.5Zr-3.0gd生物镁合金组织、力学性能及耐腐蚀性能的影响。结果表明:挤压温度在330～350℃时,动态再结晶的体积分数随挤压温度的升高而增加;在350～370℃时,动态再结晶的体积分数随温度的升高而降低。挤压... 详细信息

研究挤压温度对铸态Mg-2.0Zn-0.5Zr-3.0gd生物镁合金组织、力学性能及耐腐蚀性能的影响。结果表明:挤压温度在330～350℃时,动态再结晶的体积分数随挤压温度的升高而增加;在350～370℃时,动态再结晶的体积分数随温度的升高而降低。挤压态合金的析出相主要由纳米级的棒状(Mg, Zn)_3gd相和新析出的颗粒状Mg_2Zn_(11)相组成。合金的力学性能与动态再结晶晶粒的体积分数成正比关系。挤压温度为350℃时,合金的抗拉强度、屈服强度及伸长率分别为(247±3) MPa、(214±3) MPa和(26.7±1.1)%。随着挤压温度的升高,合金的腐蚀速率先减小后增大,挤压温度为350℃时,合金的静态腐蚀速率及析氢腐蚀速率分别为0.614 mm/a和0.598 mm/a。

关键词：镁合金微观组织生物腐蚀性能力学性能

Neutralizing Antibody Responses against Five SARS-CoV-2 Variants and T Lymphocyte Change after Vaccine Breakthrough Infections from the SARS-CoV-2 Omicron ba.1 Variant in Tianjin, China: A Prospective Study

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Biomedical and Environmental Sciences 2023年第7期36卷 614-624页

作者： ZHANg Ying QU Jiang Wen ZHENg Min Na DINg ya Xing CHEN Wei YE Shao Dong LI Xiao yan LI yan Kun LIU Ying ZHU Di JIN Can Rui WANg LIN ya.g Jin Ye ZHAI Yu WANg Er Qiang MENg Xing Tianjin Center for Disease Control and Prevention Tianjin 300011China Tianjin Key Laboratory of Pathogenic Microbiology of Infectious Disease Tianjin 300011China National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Sinovac Biotech Ltd Beijing 100085China

Objective To investigate whether Omicron ba.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity *** Blood samples were collected at two different time points from 124 Omicron ba.1 breakthrough infected patients and 124 controls matched for age,gender,and vaccination *** virus-neutralizing antibodies against five SARS-CoV-2 variants,including WT,gamma,Beta,Delta,and Omicron ba.1,and T-lymphocyte lymphocyte counts in both groups were measured and statistically *** The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron ba.1 variant at 3 months after infection,but mainly increased the antibody level against the WT strain,and the antibody against the Omicron strain was the *** neutralizing antibody level decreased rapidly 6 months after *** T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 *** Omicron ba.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron *** antibodies against the different strains declined rapidly and showed features similar to those of ***,T-lymphocytes may play an important role in recovery.

关键词： SARS-CoV-2 COVID-19 Omicron ba.1 T cells Neutralizing antibodies

Expression of CTB-human Insulin(ba. Fusion Protein in gynostemma Pentapyhllum Makino Callus Cells and Its Hypoglycemic Effect in Mice

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Chemical Research in Chinese Universities 2010年第5期26卷 773-779页

作者： WANg ya-jun QI Feng-chun HAO Shu-mei WANg Chun-yi SUI Bo SHENg Jun College of Life Science Jilin University Changchun 130012 P R. China Changchun Institute of Biological Products Changchun 130062 P R. China Changchun University of Science and Technology Changchun 130022 P. R. China Changchun Keygen Biological Products Co. Ltd. Changchun 130021 P R. China Yunnan Agricultural University Kunming 650201 P. R. China

The plant expression vector of choleratoxin B subunit（CTB）-human insulin（ba. fusion protein pBI121/（CTB-ba. was constructed first and then the gynostemma Pentapyhllum Makino callus cell line that could express CTB-human insulin fusion protein was constructed and its hypoglycemic effect was evaluated in mice. The plant expression vector pBl 121/（CTB-ba. was digested with both ba.I and SacI. Agroba.terium tumerfaciens strain Lba.404 was transformed with previously constructed recombinant plasmid pBI121/（CTB-ba. via the freeze thawing method, then CTB-ba.gene was integrated to g Pentapyhllum Makino callus cells by co-culturing the cells with the transformed Lba.404 strain. The transformed g Pentapyhllum Makino callus cells were identified by DNA sequence assey and RT-PCR. The expressed product was identified by western-blot and its amount was tested by ELISA kit and its blood sugar decreasing effect was tested in mice. The sequences of synthetic CTB and human insulin genes（ba. were completely identical to those designed. Restriction map proved that the length of gene fragment in- serted into expression vector pBI121 was consistent with that expected. The sequence of genomic DNA of expressed product was completely identical to that designed. The result of RT-PCR was consistent with that expected. The expressed product showed a specific ba.d with a relative molecular mass of 17000 by Western-blot. The human insulin expression amount was 6.03 μIU/mL according to the ELISA result. The animal test showed that only the g Pentapyhllum Makino callus cell line itself showed activity in decreasing the blood sugar of mice, however, the activity of the transformed g Pentapyhllum Makino callus cells was much higher, The plant expression vector pBI121/（CTB-ba. was constructed and expressed in the g Pentapyhllum Makino callus cells successfully for the first time. The trans- formed g Pentapyhllum Makino callus cells showed high activity in decreasing the blood sugar of mice. This stu

关键词： Human insulin peptide without C pcptide Choleratoxin B subunit g Pentapyhllum Makino callus cells

重金属絮凝剂DTMPAM去除Cr(Ⅵ)的性能与机理

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中国环境科学 2022年第12期42卷 5658-5667页

作者：周雅琦王刚张航马玉兰州交通大学环境与市政工程学院甘肃兰州730070

以二硫代羧基化羟甲基聚丙烯酰胺(DTMPAM)作为高分子絮凝剂,研究DTMPAM对水中Cr(Ⅵ)的去除性能,考察了DTMPAM投加量、pH值、Cr(Ⅵ)初始浓度以及共存浊度、无机物质、有机物质对DTMPAM处理含Cr(Ⅵ)废水性能的影响.结果表明,DTMPAM在酸性... 详细信息

以二硫代羧基化羟甲基聚丙烯酰胺(DTMPAM)作为高分子絮凝剂,研究DTMPAM对水中Cr(Ⅵ)的去除性能,考察了DTMPAM投加量、pH值、Cr(Ⅵ)初始浓度以及共存浊度、无机物质、有机物质对DTMPAM处理含Cr(Ⅵ)废水性能的影响.结果表明,DTMPAM在酸性条件下对不同Cr(Ⅵ)初始浓度的含Cr(Ⅵ)水样均具有良好的去除效果,且Cr(Ⅵ)的去除率随着体系初始pH值的降低而升高;当pH值为3.0时,DTMPAM对Cr(Ⅵ)初始浓度为5,15,25和50mg/L水样中Cr(Ⅵ)的最高去除率分别达到94.78%,96.52%,96.53%和97.49%.共存浊度对DTMPAM去除Cr(Ⅵ)具有抑制作用.在低DTMPAM投加量下,共存无机阳离子K^(+)、Na^(+)、Ca^(2+)、Mg^(2+),共存无机阴离子SO_(4)^(2-)、NO_(3)^(-)、Cl^(-),以及共存有机物质柠檬酸钠、乙酸钠、三氯乙酸和氨基乙酸等对DTMPAM去除Cr(Ⅵ)均具有一定的抑制作用;而在高DTMPAM投加量下,这些物质的存在会对DTMPAM去除Cr(Ⅵ)表现出较小的促进作用.无机阳离子Fe^(3+)、Ni^(2+)、ba.(2+)的存在对DTMPAM去除Cr(Ⅵ)具有较明显的抑制作用,其中ba.(2+)的抑制作用最显著.红外光谱和能谱分析显示,DTMPAM高分子链上的二硫代羧基可将水样中Cr(Ⅵ)还原为Cr(Ⅲ),Cr(Ⅲ)进一步和DTMPAM分子链上的二硫代羧基、胺基发生螯合反应形成絮体.

关键词：高分子絮凝剂二硫代羧基含铬废水氧化还原螯合沉淀

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博斯腾湖大湖湖区近20年生态健康状况评价

中国环境科学 2013年第3期33卷 503-507页

作者：巴雅尔郭家盛卢少勇许秋瑾胡小贞新疆巴音郭楞蒙古自治州博斯腾湖研究所新疆库尔勒841000 中国环境科学研究院环境基准与风险评估国家重点实验室国家环境保护湖泊污染控制重点实验室湖泊环境研究中心湖泊工程技术中心北京100012

为支撑博斯腾湖未来保护工作,需认知博斯腾湖近20年的生态健康状况,在对博斯腾湖大湖湖区水质状况调查基础上,适当选取系统评价指标,以1991年水质指标为本底值,运用熵权法建立湖泊生态健康评价模型,计算生态系统健康综合指数,并对博斯... 详细信息

为支撑博斯腾湖未来保护工作,需认知博斯腾湖近20年的生态健康状况,在对博斯腾湖大湖湖区水质状况调查基础上,适当选取系统评价指标,以1991年水质指标为本底值,运用熵权法建立湖泊生态健康评价模型,计算生态系统健康综合指数,并对博斯腾湖大湖湖区近20年来的健康状况进行评价.结果表明,1997、1998及2005年的水体综合状况略好于其他年份,属较好水平;而1992、1993、2003及2008年的水体综合状况则低于其他年份,属较差水平.

关键词：博斯腾湖熵权生态健康评价生态系统健康综合指数(EHCI)