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“一带一路”倡议的对外投资促进效应——基于2005—2016年中国企业绿地投资的双重差分检验 被引量:393
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作者 吕越 陆毅 +1 位作者 吴嵩博 王勇 《经济研究》 CSSCI 北大核心 2019年第9期187-202,共16页
本文采用目前可获得数据中较详实和准确的2005-2016年《全球企业绿地投资数据库》,运用事件评估的有效识别方法--双重差分法对"一带一路"倡议的投资促进效应进行全方位的评析。主要结论是:首先,"一带一路"倡议实施... 本文采用目前可获得数据中较详实和准确的2005-2016年《全球企业绿地投资数据库》,运用事件评估的有效识别方法--双重差分法对"一带一路"倡议的投资促进效应进行全方位的评析。主要结论是:首先,"一带一路"倡议实施显著促进了中国企业对外绿地投资的增长,"一带一路"沿线国家的投资项目数增长幅度达32%左右,且一系列的有效性和稳健性检验均表明这一促进效应显著存在。其次,"一带一路"倡议对中国企业绿地投资的积极促进效应通过"五通"实现,即设施联通、政策沟通、资金融通、贸易畅通、民心相通。再次,通过异质性分析发现,在地理上,"一带一路"倡议更显著地促进"海上丝绸之路"沿线国家和与中国邻近"一带一路"国家的投资增长,且对高政治风险经济体的投资不存在显著的促进效应。从投资动态来看,现阶段"一带一路"倡议的投资促进效应主要表现为集约边际的扩张,即主要带动已有投资基础或投资项目经济体的投资增长。此外,基于三重差分估计的结果看,在行业上,该倡议的对外投资促进效应主要集中在能源、交通和通信等基础设施相关领域;在投资来源上,该倡议尚未对"一带一路"重点省份产生显著的投资促进效应。 展开更多
关键词 "一带一路" 对外直接投资 双重差分 绿地投资 "五通"
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No-reflow protection and long-term efficacy for acute myocardial infarction with Tongxinluo: a randomized double-blind placebo- controlled multicenter clinical trial (ENLEAT Trial) 被引量:77
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作者 ZHANG Hai-tao JIA Zhen-hua +7 位作者 ZHANG Jian YE Zan-kai YANG Wei-xian TIAN yue-qin JIA Xuan LI Wei WU yi-ling YANG yue-jin 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第20期2858-2864,共7页
Background No-reflow after emergency percutaneous coronary intervention (PCI) for acute ST segment elevation myocardial infarction (STEMI) is related to the severe prognosis. The aim of this study was to evaluate ... Background No-reflow after emergency percutaneous coronary intervention (PCI) for acute ST segment elevation myocardial infarction (STEMI) is related to the severe prognosis. The aim of this study was to evaluate the efficacy of Tongxinluo, a traditional Chinese medicine, on no-reflow and the infarction area after emergency PCI for STEMI.Methods A total of 219 patients (female 31, 14%) undergoing emergency PCI for STEMI from nine clinical centers were consecutively enrolled in this randomized, double-blind, placebo-controlled, multicenter clinical trial from January 2007 to May 2009. All patients were randomly divided into Tongxinluo group (n=108) and control group (n=111), given Tongxinluo or placebo in loading dose 2.08 g respectively before emergency PCI with asprin 300 mg and clopidogrel 300 mg together, then 1.04 g three times daily for six months after PCI. The ST segment elevation was recorded by electrocardiogram at hospitalization and 1, 2, 6, 12, 24 hours after coronary balloon dilation to evaluate the myocardial no-flow; myocardial perfusion scores of 17 segments were evaluated on day 7 and day 180 after STEMI with static single-photon emission computed tomography (SPECT) to determine the infarct area.Results There was no statistical significance in sex, age, past history, chest pain, onset-to-reperfusion time, Killip classification, TIMI flow grade just before and after PCI, either in the medication treatment during the follow up such as statin, β-blocker, angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) between two groups. There was significant ST segment restoration in Tongxinluo group compared to the control group at 6 hours ((-0.22±0.18) mV vs. (-0.18±0.16) mV, P=0.0394), 12 hours ((-0.24 ± 0.18) mV vs. (-0.18±0.15) mV, P=0.0158) and 24 hours ((-0.27±0.16) mV vs. (-0.20±0.16) mV, P=0.0021) reperfusion; and the incidence of myocardial no-reflow was also reduced significantly at 24-hour rep 展开更多
关键词 acute myocardial infarction NO-REFLOW percutaneous coronary intervention TONGXINLUO
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水风光多能互补发电调度问题研究现状及展望 被引量:69
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作者 申建建 王月 +4 位作者 程春田 李秀峰 苗树敏 张一 张俊涛 《中国电机工程学报》 EI CSCD 北大核心 2022年第11期3871-3884,共14页
以水风光为主的可再生能源在过去二十年实现了前所未有的发展,未来也将是中国构建清洁低碳能源体系的核心组成部分,是兑现碳减排承诺的现实选择。该文简要分析了我国清洁能源发电的发展概况及典型水风光互补实际工程,提炼总结了互补系... 以水风光为主的可再生能源在过去二十年实现了前所未有的发展,未来也将是中国构建清洁低碳能源体系的核心组成部分,是兑现碳减排承诺的现实选择。该文简要分析了我国清洁能源发电的发展概况及典型水风光互补实际工程,提炼总结了互补系统发电调度面临的关键问题,包括大规模风光电站群以何种形式参与调度、间歇性时空发电规律如何描述、风光电站群与水电站群在长期、短期等时间尺度上如何协调运行;针对这些问题系统综述了国内外水风光互补协调研究方法及特点,并从风光电站集群汇聚、集群出力描述、及集群模式下水风光互补系统长期、短期协调建模与求解思路,阐述了技术实现过程,期望为我国多能互补工程实际运行提供切实可用的技术手段,助力“碳达峰、碳中和”目标。 展开更多
关键词 多能互补 水风光系统 出力不确定性 灵活性 协调控制
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Dexamethasone-induced adipogenesis in primary marrow stromal cell cultures: mechanism of steroid-induced osteonecrosis 被引量:60
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作者 yiN Li LI yue-bai WANG yi-sheng 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第7期581-588,共8页
Background In steroid-induced osteonecrosis, hypertrophy and hyperplasia of marrow fat cells and lipid deposition of osteocytes can be found in the femoral head. However, the precise reason is not clear yet. The aim o... Background In steroid-induced osteonecrosis, hypertrophy and hyperplasia of marrow fat cells and lipid deposition of osteocytes can be found in the femoral head. However, the precise reason is not clear yet. The aim of this study was to observe the effect of dexamethasone (Dex) on differentiation of marrow stromal cells (MSCs), and to investigate the pathobiological mechanism of steroid-induced osteonecrosis.Methods MSCs in cultures were treated with increasing concentrations of Dex (0, 10^-9, 10^-8, 10^-7, and 10^-6 mol/L) continuously for 21 days. The cells, which were exposed to 0 mol/L (control) or 10^-7 mol/L Dex for 4-21 days, were then cultured for 21 days without Dex. MSCs were stained with Sudan Ⅲ. Number of adipocytes was counted under a light microscope. The activity of alkaline phosphatase (ALP) of MSCs treated with 0, 10^-8, 10-7, and 10^-6 mol/L Dex for 12 days, and that treated with 0 mol/L and 10^-7 mol/L Dex for 8, 10, or 12 days were determined. The levels of triglycerides, osteocalcin and cell proliferation of MSCs treated with 0 mol/L and 10^-7 mol/L Dex were detected. The mRNA expression levels of adipose-specific 422(aP2) gene and osteogenic gene type I collagen in MSCs treated with 0 mol/L and 10^-7 mol/L Dex for 6 days were analyzed by whole-cell dot-blot hybridization. Statistical analysis was performed using Student's t test and analysis of variance. P values less than 0.05 were considered significant statistically.Results The number of adipocytes in cultures increased with the duration of MSCs' exposure to Dex and the concentration of Dex. The level of ALP activity in the MSCs decreased with concentration of Dex. In the control group, it was 8.69 times of that in the 10^-7 mol/L Dex group on day 12 (t=20.51, P〈0.001). The level of triglycerides in 10^-7 mol/L Dex group was 3.40 times of that in the control (t=11.00, P〈0.001). The levels of cell proliferation and osteocalcin in the control were 1.54 and 2.42 times of that in the 10^-7 mol/L Dex g 展开更多
关键词 DEXAMETHASONE bone marrow ADIPOCYTES OSTEONECROSIS
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基于生态足迹法的闽三角城市群生态安全评价 被引量:61
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作者 魏黎灵 李岚彬 +2 位作者 林月 吴仪 祁新华 《生态学报》 CAS CSCD 北大核心 2018年第12期4317-4326,共10页
生态安全已经成为时下研究的热点问题,而生态足迹法(Ecological Footprint)是评价区域生态安全的重要方法之一。然而,目前鲜有应用改良后的生态足迹方法探讨海湾型城市群生态足迹以及生态安全状态的成果。鉴于此,论文以闽三角城市群为... 生态安全已经成为时下研究的热点问题,而生态足迹法(Ecological Footprint)是评价区域生态安全的重要方法之一。然而,目前鲜有应用改良后的生态足迹方法探讨海湾型城市群生态足迹以及生态安全状态的成果。鉴于此,论文以闽三角城市群为研究区,以NPP数据反映现实生物量,采用"国家公顷"实现产量因子区域化,测算2010—2015年的区域生态足迹、生态承载力、生态赤字以及生态压力指数,评价区域生态安全状态。结果表明:2010—2015年间,闽三角城市群的生态足迹快速增长,其中泉州与漳州增长迅速,而厦门则略有下降;区域总体生态承载力缓慢下降;城市群大部分区域呈现生态赤字且越发严重,其中厦门最为严重,泉州次之,漳州相对较轻;城市群生态压力指数持续增长,生态安全等级升高,与生态赤字情况总体相符,生态安全问题亟需解决。有助于拓展与丰富生态足迹与生态安全研究的视角与案例,并为城市群可持续发展提供科学依据和决策支撑。 展开更多
关键词 生态足迹 净初级生产力 生态安全 闽三角城市群
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计及需求响应不确定性的综合能源系统协同优化配置 被引量:51
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作者 刘文霞 李征洲 +2 位作者 杨粤 伊放 王尧 《电力系统自动化》 EI CSCD 北大核心 2020年第10期41-49,共9页
提出了一种计及综合需求响应(IDR)不确定性的综合能源系统(IES)设备优化配置方法。首先,以提高能源利用效率为目标,基于冷/热/电联供系统构建了计及IDR的IES基本结构。然后,采用证据理论对IDR中的随机和认知不确定性进行分析,并利用可... 提出了一种计及综合需求响应(IDR)不确定性的综合能源系统(IES)设备优化配置方法。首先,以提高能源利用效率为目标,基于冷/热/电联供系统构建了计及IDR的IES基本结构。然后,采用证据理论对IDR中的随机和认知不确定性进行分析,并利用可信水平约束,优化一定电价方案下的负荷曲线。在此基础上,建立兼顾设备优化配置及运行策略的双层协同规划模型,上层以规划总成本最低为目标进行设备选型和容量配置,下层以运行成本最低为目标优化设备出力。通过比较所有电价方案下的总成本,获得最优电价与设备配置方案。最后,通过算例验证了计及IDR不确定性的优化配置结果对风险的抵御能力更强,且采用证据理论能够实现概率理论和区间理论的统一。 展开更多
关键词 综合能源系统 综合需求响应 证据理论 不确定性 优化配置
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2022年中国储能技术研究进展 被引量:44
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作者 陈海生 李泓 +53 位作者 徐玉杰 陈满 王亮 戴兴建 徐德厚 唐西胜 李先锋 胡勇胜 马衍伟 刘语 苏伟 王青松 陈军 卓萍 肖立业 周学志 冯自平 蒋凯 尉海军 唐永炳 陈人杰 刘亚涛 张宇鑫 林曦鹏 郭欢 张涵 张长昆 胡东旭 容晓晖 张熊 金凯强 姜丽华 彭煜民 刘世奇 朱轶林 王星 周鑫 欧学武 庞全全 俞振华 刘为 岳芬 李臻 宋振 王志峰 宋文吉 林海波 李杰才 易斌 李福军 潘新慧 李丽 马一鸣 李煌 《储能科学与技术》 CAS CSCD 北大核心 2023年第5期1516-1552,共37页
本文对2022年度中国储能技术的研究进展进行了综述。通过对基础研究、关键技术和集成示范三方面的回顾和分析,总结了2022年中国储能领域的主要技术进展,包括抽水蓄能、压缩空气储能、飞轮储能、锂离子电池、铅蓄电池、液流电池、钠离子... 本文对2022年度中国储能技术的研究进展进行了综述。通过对基础研究、关键技术和集成示范三方面的回顾和分析,总结了2022年中国储能领域的主要技术进展,包括抽水蓄能、压缩空气储能、飞轮储能、锂离子电池、铅蓄电池、液流电池、钠离子电池、超级电容器、新型储能技术、集成技术和消防安全技术等。结果表明,2022年中国储能技术在基础研究、关键技术和集成示范方面均有重要进展,中国已成为世界储能技术基础研究、技术研发和集成应用最活跃的国家。 展开更多
关键词 储能 技术 进展
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Effects of propofol, dexmedetomidine, and midazolam on postoperative cognitive dysfunction in elderly patients: a randomized controlled preliminary trial 被引量:40
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作者 Wei-Xia Li Ru-yi Luo +4 位作者 Chao Chert Xiang Li Jing-Sheng AO yue Liu yi-Qing yin 《Chinese Medical Journal》 SCIE CAS CSCD 2019年第4期437-445,共9页
Background: Postoperative cognitive dysfunction (POCD) is a serious complication after surgery, especially in elderly patients. The anesthesia technique is a potentially modifiable risk factor for POCD. This study ass... Background: Postoperative cognitive dysfunction (POCD) is a serious complication after surgery, especially in elderly patients. The anesthesia technique is a potentially modifiable risk factor for POCD. This study assessed the effects of dexmedetomidine, propofol or midazolam sedation on POCD in elderly patients who underwent hip or knee replacement under spinal anesthesia. Methods: The present study was a prospective randomized controlled preliminary trial. From July 2013 and December 2014, a total of 164 patients aged 65 years or older who underwent hip or knee arthroplasty at China-Japan Friendship Hospital and 41 non-surgical controls were included in this study. Patients were randomized in a 1:1:1 ratio to 3 sedative groups. All the patients received combined spinal-epidural anesthesia (CSEA) with midazolam, dexmedetomidine or propofol sedation. The sedative dose was adjusted to achieve light sedation (bispectral index[BIS] score between 70 and 85). All study participants and controls completed a battery of 5 neuropsychological tests before and 7 days after surgery. One year postoperatively, the patients and controls were interviewed over the telephone using the Montreal cognitive assessment 5-minute protocol. Results: In all, 60 of 164 patients (36.6%) were diagnosed with POCD 7 days postoperatively, POCD incidence in propofol group was significantly lower than that in dexmedetomidine and midazolam groups (18.2% vs. 40.0%, 51.9%, χ^2 6.342 and 13.603, P= 0.012 and < 0.001). When the patients were re-tested 1 year postoperatively, the incidence of POCD was not significantly different among the 3 groups (14.0%, 10.6% vs. 14.9%, χ^2 0.016 and 0.382, P= 0.899 and 0.536). Conclusion: Among dexmedetomidine, propofol and midazolam sedation in elderly patients, propofol sedation shows a significant advantage in term of short-term POCD incidence. 展开更多
关键词 Cognitive dysfunction NEUROPSYCHOLOGICAL tests POSTOPERATIVE period SEDATIVES
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Analysis of Factors Associated with Death in Maintenance Hemodialysis Patients: A Multicenter Study in China 被引量:40
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作者 Kang-Kang Song De-Long Zhao +19 位作者 Yuan-Da Wang Yong Wang Xue-Feng Sun Li-Ning Miao Zhao-Hui Ni Hong-Li Lin Fu-You Liu ying Li Ya-Ni He Nian-Song Wang Cai-Li Wang Ai-Hua Zhang Meng-Hua Chen Xiao-Ping Yang yue-yi Deng Feng-Min Shao Shu-Xia Fu Jing-Ai Fang Guang-Yan Cai Xiang-Mei Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第8期885-891,共7页
Background: Patients on hemodialysis have a high-mortality risk. Tiffs study analyzed factors associated with death in patients on maintenance hemodialysis (MHD). While some studies used baseline data of MHD patien... Background: Patients on hemodialysis have a high-mortality risk. Tiffs study analyzed factors associated with death in patients on maintenance hemodialysis (MHD). While some studies used baseline data of MHD patients, this study used the most recent data obtained from patients just prior to either a primary endpoint or the end of the study period to iliad the characteristics of patients preceding death.Methods: Participants were selected from 16 blood purification centers in China from January 2012 to December 2014, Patients' data were collected retrospectively. Based on survival status, the participants were divided into two groups: survival group and the death group. Logistic regression analysis was performed to determine/'actors associated with all-cause mortality. 展开更多
关键词 HEMODIALYSIS Mortality: Risk Factors
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Inhibition of Dual Specific Oncolytic Adenovirus on Esophageal Cancer via Activation of Caspases by a Mitochondrial-dependent Pathway 被引量:38
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作者 SU Jia-qiang CHI Bao-rong +5 位作者 LI Xiao LIU Lei LIU Li-ming QI Yan-xin WANG Zhuo-yue JIN Ning-yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期465-471,共7页
We investigated the anti-tumor effects of dual cancer specific-oncolytic adenovirus Ad-VP on esophageal cancer(EC). The anti-tumor activity of Ad-VP was compared with that of the control recombinant adenoviruses (A... We investigated the anti-tumor effects of dual cancer specific-oncolytic adenovirus Ad-VP on esophageal cancer(EC). The anti-tumor activity of Ad-VP was compared with that of the control recombinant adenoviruses (Ad-GP, Ad-Apoptin, Ad-EGFP) in human esophageal cancer cell EC-109 and human normal liver cell L02 in vitro. In 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assays, the growth of EC-109 cells was slightly inhibited by Ad-GP, Ad-Apoptin and Ad-EGFE However, Ad-VP induced a significant cytotoxic effect. Infection of EC-109 cells with Ad-VP resulted in a significant induction of apoptosis of them in vitro, detected by 4',6-diamidino-2-phenylindole(DAPI) or acridine orange and ethidium bromide staining. The results of Western blot and flow cytometric assay indicate the loss of mitochondrial membrane potential(Aψm), the release of eytochrome c and the activation of caspase-3, 6 and 7 in Ad-VP infected EC-109 cells. In contrast, all these assays show almost no effects of the recombinant adenoviruses on L02 cells. These results demonstrate that the treatment of tumors with Ad-VP selectively inhibits tumor growth and induces apoptosis of esophageal cancer cells. Ad-VP may provide a novel and powerful strategy for cancer gene therapy. 展开更多
关键词 APOPTIN Apoptosis ANTI-TUMOR Esophageal cancer Recombinant adenovirus
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Intravoxel incoherent motion diffusion-weighted magnetic resonance imaging for predicting histological grade of hepatocellular carcinoma:Comparison with conventional diffusion-weighted imaging 被引量:36
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作者 Shao-Cheng Zhu yue-Hua Liu +4 位作者 yi Wei Lin-Lin Li She-Wei Dou Ting-yi Sun Da-Peng Shi 《World Journal of Gastroenterology》 SCIE CAS 2018年第8期929-940,共12页
AIM To compare intravoxel incoherent motion(IVIM)-derived parameters with conventional diffusion-weighted imaging(DWI) parameters in predicting the histological grade of hepatocellular carcinoma(h CC) and to evaluate ... AIM To compare intravoxel incoherent motion(IVIM)-derived parameters with conventional diffusion-weighted imaging(DWI) parameters in predicting the histological grade of hepatocellular carcinoma(h CC) and to evaluate the correlation between the parameters and the histological grades.METHODS A retrospective study was performed. Sixty-two patients with surgically confirmed h CCs underwent diffusion-weighted magnetic resonance imaging with twelve b values(10-1200 s/mm^2). The apparent diffusion coefficient(ADC), pure diffusion coefficient(D), pseudo-diffusion coefficient(D*), and perfusion fraction(f) were calculated by two radiologists. The IVIM and conventional DWI parameters were compared among the different grades by using analysis of variance(ANOVA) and the Kruskal-Wallis test. Receiver operating characteristic(ROC) analysis was performed to evaluate the diagnostic efficiency of distinguishing between low-grade(grade 1, G1) and high-grade(grades 2 and 3, G2 and G3) hC C. The correlation between the parameters and the histological grades was assessed by using the Spearman correlation test. Bland-Altman analysis was used to evaluate the reproducibility of the two radiologists' measurements.RESULTS The differences in the ADC and D values among the groups with G1, G2, and G3 histological grades of HCCs were statistically significant(P < 0.001). The D* and f values had no significant differences among the different histological grades of h CC(P > 0.05). The ROC analyses demonstrated that the D and ADC values had better diagnostic performance in differentiating the low-grade h CC from the high-grade h CC, with areas under the curve(AUCs) of 0.909 and 0.843, respectively, measured by radiologist 1 and of 0.911 and 0.852, respectively, measured by radiologist 2. The following significant correlations were obtained between the ADC, D, and D~* values and the histological grades: r =-0.619(P < 0.001), r =-0.628(P < 0.001), and r =-0.299(P = 0.018), respectively, as measured by radiologist 1; r =-0.622(P < 0.001), r =-0.63 展开更多
关键词 Intravoxel INCOHERENT motion Diffusionweighted imaging HEPATOCELLULAR CARCINOMA PATHOLOGICAL DIFFERENTIATION GRADE
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中国北方六省(自治区)儿童2019新型冠状病毒感染31例临床分析 被引量:36
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作者 王端 鞠秀丽 +21 位作者 谢峰 芦燕 李飞宇 黄辉红 方秀玲 李元军 王建云 易彬 岳菊侠 王静 王凌啸 李博 王义 邱丙平 周志远 李可亮 孙建华 刘学工 李国栋 王永军 曹爱华 陈艳妮 《中华儿科杂志》 CAS CSCD 北大核心 2020年第4期269-274,共6页
目的 分析中国北方6省(自治区)儿童2019新型冠状病毒(2019-nCoV)感染者的流行病学史、临床表现、治疗及近期预后。方法 回顾性总结陕西、甘肃、宁夏、河北、河南、山东6省(自治区)17市21家医院于2020年1月25日至2月21日经2019-nCoV核酸... 目的 分析中国北方6省(自治区)儿童2019新型冠状病毒(2019-nCoV)感染者的流行病学史、临床表现、治疗及近期预后。方法 回顾性总结陕西、甘肃、宁夏、河北、河南、山东6省(自治区)17市21家医院于2020年1月25日至2月21日经2019-nCoV核酸检测确诊的31例患儿的病例资料,分析其流行病学史、临床症状、体征、实验室检查、胸部影像学以及治疗和近期预后情况。结果 31例患儿年龄7岁1月龄(6月龄~17岁)。9例(29%)为输入性病例,21例(68%)有确诊成人患者接触史,1例(3%)曾接触过无症状的武汉返乡人员。31例患儿中28例(90%)为家庭聚集性发病。临床分型为无症状型4例(13%),轻型13例(42%),普通型14例(45%),无重型及危重型。症状发生频率最高为发热(20例,65%),其中高热1例、中度发热9例、低热10例,热程1~9 d,15例≤3 d,5例>3 d;其余依次为咳嗽(14例,45%),乏力(3例,10%),腹泻(3例,10%),咽痛、流涕、头晕、头痛、呕吐等少见。早期外周血白细胞总数减少者、淋巴细胞数减少者、血小板增多者各2例(6%)。C反应蛋白升高(10%,3/30),红细胞沉降率升高(19%,4/21),降钙素原升高(4%,1/28),血清转氨酶升高(22%,6/27)及肌酶升高(15%,4/27)也有不同比例出现。检测肾功能及血糖者均未见异常。14例患儿胸部CT有异常改变,其中9例呈斑片状磨玻璃阴影及结节,多位于双肺中外带、近胸膜区。31例患儿给予一般治疗后25例病毒核酸检测转阴(7~23 d),其中24例(77%)痊愈出院,无死亡病例。结论 中国北方6省(自治区)31例儿童2019-nCoV感染以家庭内密切接触为主要感染途径,呈无症状型、轻型和普通型,临床表现及实验室检查结果无特异性。流行病学密切接触史、病毒核酸检测及胸部影像学是儿童2019-nCoV感染诊断的重要参考依据,给予一般治疗,近期预后整体良好。 展开更多
关键词 疾病特征 2019新型冠状病毒 儿童
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-Heng Zhao +134 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai yue Wu Yan Cai Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-Ning Li Jian Li Qi Li Shuang Li Sha-Sha Li Xin-Nan Li Yan Li yin-Bi Li Ye-Ping Li Yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-Xiang Qi Yong-Jun Qi Shi-yin Shen Huo-Ming Shi Jing Song yi-Han Song Ding-Qiang Su Hong-Jun Su Zheng-Hong Tang Qing-Sheng Tao Yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-Ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang Meng-Xin Wang Shou-Guan Wang Shu-Qing Wang Xia Wang Ya-Nan Wang You Wang yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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经皮微波消融治疗自主功能性甲状腺结节的临床研究 被引量:31
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作者 陈吉东 岳林先 +7 位作者 尹立雪 陈琴 熊晏群 冯超 顾毅 黄际远 朱鸿 张磊 《中华超声影像学杂志》 CSCD 北大核心 2018年第11期958-962,共5页
目的研究微波消融(microwave ablation,MWA)治疗自主功能性甲状腺结节(autonomous functional thyroid nodules,AFTN)的临床疗效及安全性。方法收集拒绝或不适合外科切除手术和131I治疗的AFTN患者53例共67个结节纳入研究。所有结节均行... 目的研究微波消融(microwave ablation,MWA)治疗自主功能性甲状腺结节(autonomous functional thyroid nodules,AFTN)的临床疗效及安全性。方法收集拒绝或不适合外科切除手术和131I治疗的AFTN患者53例共67个结节纳入研究。所有结节均行常规超声、彩色多普勒血流显像(color Doppler flow imaging,CDFI)及超声造影评估均为良性声像特征,并经病理证实,再行经皮MWA。采取液体隔离及移动消融等技术,并用超声造影实时监测及疗效评估。观察项目:甲状腺激素水平、结节体积、结节血供、核素显像、自觉症状及美容评分、并发症,最后分析影响MWA疗效的因素。结果所有病例随访>12个月。甲状腺激素水平、结节体积、结节血供与治疗前比较差异均具有统计学意义(P<0.01)。61个“热结节”变为“冷或温结节”。自觉症状和美容评分改善率的差异具有统计学意义(P<0.05)。本研究中痊愈率81.13%,并发症发生率为11.32%,复发率为4.48%。治疗前结节体积≥14.04ml和危险部位为影响疗效的主要因素。结论MWA能原位灭活AFTN,使其分泌功能丧失并逐步缩小。常规超声和超声造影引导下经皮MWA治疗AFTN可视为除外科切除手术和131I治疗以外的另一种安全有效治疗方式。 展开更多
关键词 超声造影 微波消融术 甲状腺结节 临床疗效
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Pretreatment with Tongxinluo protects porcine myocardium from ischaemia/reperfusion injury through a nitric oxide related mechanism 被引量:28
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作者 CHENG Yu-tong YANG yue-jin +5 位作者 ZHANG Hai-tao QIAN Hai-yan ZHAO Jing-lin MENG Xian-min LUO Fu-liang WU yi-ling 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第13期1529-1538,共10页
Background The traditional Chinese medicine injury, but the mechanism of its action is not we protective role of Tongxinluo. Tongxinluo can protect myocardium against documented. We examined the involvement schaemia/r... Background The traditional Chinese medicine injury, but the mechanism of its action is not we protective role of Tongxinluo. Tongxinluo can protect myocardium against documented. We examined the involvement schaemia/reperfusion of nitric oxide in the Methods Miniswine were randomized to four groups of seven: sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor N^ωnitro-L-arginine (L-NNA, 10 mg/kg i.v.). Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively. Results Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA. Conclusions Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase. 展开更多
关键词 myocardial infarction myocardial reperfusion injury nitric oxide drugs Chinese Herbal neutrophil infiltration
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基于InVEST模型的鄱阳湖区生境质量时空演化及其变迁特征分析 被引量:27
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作者 尚俊 蔡海生 +3 位作者 龙月 曾君乔 陈艺 张学玲 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2021年第8期1901-1915,共15页
鄱阳湖是国际重要湿地、全球重要的生态区,鄱阳湖区生态环境质量对于鄱阳湖生态功能、生物多样性保护具有极其重要的意义。基于鄱阳湖区1995、2005、2015年遥感影像数据,采用InVEST模型,分析了湖区生境质量时空演变情况;利用像元二分法... 鄱阳湖是国际重要湿地、全球重要的生态区,鄱阳湖区生态环境质量对于鄱阳湖生态功能、生物多样性保护具有极其重要的意义。基于鄱阳湖区1995、2005、2015年遥感影像数据,采用InVEST模型,分析了湖区生境质量时空演变情况;利用像元二分法,对生境退化度的概率密度函数与累积分布函数计算分析,明确了湖区生境退化的阈值;结合标准差椭圆分析法,探讨了不同生态类型生境质量优势变迁情况。结果表明:(1)鄱阳湖区1995~2015年建设用地大幅增长,耕地、林地面积小幅下降,草地面积严重减少,水域、其他用地面积小幅增加。(2)鄱阳湖区耕地、林地、草地、水域生境的强干扰阈值,分别为各自生境适宜度的70%、85%、81%、78%。水域、林地、草地受到的干扰逐渐增强,耕地受到的干扰逐渐减弱。(3)鄱阳湖区1995~2015年生境质量略微下降,中心地带的水域以及北部地区的林地干扰较弱,区域生境质量较高;中心地带外沿环层生境质量一般;西南部耕地干扰较强,区域生境质量较低。高质量生境向低质量生境演化现象严峻。(4)耕地变迁态势反映出耕地保护政策的严格化;林草地变迁态势受到地形梯度因素的影响;水域变迁态势受围湖造田和城镇扩张共同影响,单一从土地利用层面解释湿地水域生境质量演变存在局限性。研究结果对于鄱阳湖区生态环境保护及生态系统调控具有一定的理论意义与实践价值。 展开更多
关键词 鄱阳湖区 生境质量 InVEST模型 像元二分法 标准差椭圆法
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MicroRNA Expression Profiles and MiR-10a Target in Anti-benzo[a] pyrene-7,8-diol-9,10-epoxide-transformed Human 16HBE Cells 被引量:26
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作者 yue-LAN SHEN yi-Guo JIANG +2 位作者 ANNE R. GREENLEE LAN-LAN ZHOU LIN-HUA LIU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第1期14-21,共8页
Objective To screen miRNA profiles of malignantly transformed human bronchial epithelial cells, 16HBE-T, induced by anti-benzo[a]pyrene-trans-7,8-diol-9,10-epoxide (anti-BPDE), and to analyze putative miR-10a target... Objective To screen miRNA profiles of malignantly transformed human bronchial epithelial cells, 16HBE-T, induced by anti-benzo[a]pyrene-trans-7,8-diol-9,10-epoxide (anti-BPDE), and to analyze putative miR-10a targets in 16HBE-T. Methods A novel microarray platform was employed to screen miRNA profiles of 16HBE-T cells transformed by anti-BPDE. Microarray data for miR-10a and miR-320 were validated using quantitative real time polymerase chain reaction (QRT-PCR). The expression of a putative target for miR-10a, HOXA1, was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and QRT-PCR. Results In comparison with the vehicle-treated cells (16HBE-N), 16HBE-T exhibited differential expression of 54 miRNAs, in which, 45 were over-expressed and 9 were down-regulated. The five most highly expressed miRNAs were miR-494, miR-320, miR-498, miR-129, and miR-106a. The lowest expressed miRNAs were miR-10a, miR-493-5p, and miR-363*. Three members of miR-17-92 cluster, miR-17-5p, miR-20a, and miR-92, showed significantly higher abundance in 16BHE-T as miR-21, miR-141, miR-27a, miR-27b, miR-16 and miRNAs of the let-7 family. The putative target for miR-10a, HOXA1 mRNA was up-regulated 3-9-fold in 16HBE-T, as compared with 16HBE-N. Conclusion The findings of the study provide information on differentially expressed miRNA in malignant 16HBE-T, and also suggest a potential role of these miRNAs in cell transformation induced by anti-BPDE. HOXA1 is similarly up-regulated, suggesting that miR-10a is associated with the process of HOXA 1-mediated transformation. 展开更多
关键词 MICRORNA Anti-BPDE Malignant transformation 16HBE
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基于深度学习的无人机遥感生态灌区杂草分类 被引量:25
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作者 王术波 韩宇 +3 位作者 陈建 潘越 曹毅 孟灏 《排灌机械工程学报》 EI CSCD 北大核心 2018年第11期1137-1141,共5页
为了更好地推进生态灌区建设,对灌区内杂草进行检测、控制,提出一种基于卷积神经网络的杂草分类和密度测算方法.通过无人机低空拍摄采集3种杂草(藜草、葎草、苍耳)和3种作物(小麦、花生、玉米)作为数据集,经过裁剪、灰度化等前期处理,... 为了更好地推进生态灌区建设,对灌区内杂草进行检测、控制,提出一种基于卷积神经网络的杂草分类和密度测算方法.通过无人机低空拍摄采集3种杂草(藜草、葎草、苍耳)和3种作物(小麦、花生、玉米)作为数据集,经过裁剪、灰度化等前期处理,并通过旋转方式扩充数据集,最后收集17 115张训练样本和750张测试样本,然后将训练集输送给卷积神经网络,采用Softmax回归,实现6类植物的分类.为降低网络参数,文中试验了100×100和300×300不同分辨率图像对识别精度的影响,分类结果表明300×300分辨率时识别率最高可达到95.6%.另外为实现针对特定杂草的防控,提出了一种检测单一杂草密度的方法,可实现对灌区内各种杂草的精确监控,为后期杂草防控的精准施药提供依据,对实现高效、绿色、安全的现代农业具有重要理论意义和实用价值. 展开更多
关键词 生态灌区 无人机 卷积神经网络 杂草分类
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Quantitative evaluation of diffusion-weighted magnetic resonance imaging of focal hepatic lesions 被引量:21
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作者 Xi-Jie Sun Xian-yue Quan +1 位作者 Fan-Heng Huang yi-Kai Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第41期6535-6537,共3页
AIM: To explore the quantitative analysis of diffusionweighted magnetic resonance imaging (DWMRI) in differential diagnosis of focal hepatic lesions.METHODS: DWMRI was performed in 149 hepatic lesions, including hepat... AIM: To explore the quantitative analysis of diffusionweighted magnetic resonance imaging (DWMRI) in differential diagnosis of focal hepatic lesions.METHODS: DWMRI was performed in 149 hepatic lesions, including hepatocellular carcinoma (34 cases),hepatic metastases (37 cases), cavernous hemangioma (42 cases), hepatic cyst (36 cases). Apparent diffusion coefficient (ADC) values were evaluated using four different b values in different sequences. The ratio of ADC values of lesion/liver in hepatocellular carcinoma and hepatic metastases was also calculated.RESULTS: The mean ADC values of hepatic lesions were as follows: hepatocellular carcinoma (0.95 ± 0.11) × 10-3 mm2/s, hepatic metastasis (1.13 ± 0.21)× 10-3 mm2/s, cavernous hemangioma (1.86±0.36)×10-3 mm2/s,hepatic cyst(3.14±0.31)×10-3 mm2/s. The ratio of ADC values in lesion/liver in hepatocellular carcinoma was 0.91 ±0.11, being significantly different from that in hepatic metastasis (1.21 ± 0.18, P< 0.05).CONCLUSION: ADC values and quantitative analysis of focal hepatic lesions are of significant values in differential diagnosis of focal hepatic lesions. 展开更多
关键词 Diffusion-weighed magnetic resonance imaging Hepatic lesion Quantitative analysis
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爆破片失效影响因素分析及失效案例 被引量:24
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作者 闫兴清 喻健良 +4 位作者 李岳 温殿江 伊军 韩冰 胡军 《压力容器》 北大核心 2018年第8期52-57,共6页
频繁发生的爆破片失效事故,为具有超压风险的容器及设备的安全运行带来了隐患。分析了可能引起爆破片失效的8个因素,分别为设计爆破压力或操作压力不当、设计爆破温度或操作温度不当、内部介质腐蚀、外部环境腐蚀、夹持力不足或不均匀... 频繁发生的爆破片失效事故,为具有超压风险的容器及设备的安全运行带来了隐患。分析了可能引起爆破片失效的8个因素,分别为设计爆破压力或操作压力不当、设计爆破温度或操作温度不当、内部介质腐蚀、外部环境腐蚀、夹持力不足或不均匀、爆破片磕碰或损伤、爆破片进出口法兰配合不当、爆破片泄压侧防护不当等因素,详细探讨了各因素对爆破片爆破性能的影响规律,并给出了事故案例,可为防止爆破片发生类似失效事故提供参考。 展开更多
关键词 爆破片 失效 影响因素 事故案例
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