期刊文献+
共找到1,047篇文章
< 1 2 53 >
每页显示 20 50 100
Stable classi?cation with limited sample: transferring a 30-m resolution sample set collected in 2015 to mapping 10-m resolution global land cover in 2017 被引量:183
1
作者 Peng Gong Han Liu +28 位作者 Meinan Zhang Congcong Li Jie Wang Huabing Huang Nicholas Clinton Luyan Ji Wenyu Li Yuqi Bai Bin Chen Bing Xu Zhiliang Zhu Cui Yuan Hoi Ping Suen Jing Guo Nan Xu Weijia Li Yuanyuan Zhao Jun Yang Chaoqing Yu Xi Wang Haohuan Fu le Yu Iryna Dronova Fengming Hui Xiao Cheng Xueli shi Fengjin Xiao Qiufeng Liu Lianchun Song 《Science Bulletin》 SCIE EI CAS CSCD 2019年第6期370-373,共4页
As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, envir... As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations. 展开更多
关键词 the world strives to REDUCE timely and HIGHER RESOLUTION information is urgently needed
原文传递
Hepatic artery infusion chemotherapy using mFOLFOX versus transarterial chemoembolization for massive unresectable hepatocellular carcinoma:a prospective non.randomized study 被引量:110
2
作者 Min-Ke He Yong le +5 位作者 Qi-Jiong Li Zi-Shan Yu Shao-Hua Li Wei Wei Rong-Ping Guo Ming shi 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第12期704-711,共8页
Background: Transarterial chemoembolization(TACE) is recommended as the standard care for unresectable hepatocellular carcinoma(HCC) at Barcelona Clinic Liver Cancer(BCLC) stage A-B. However, the efficacy of TACE on l... Background: Transarterial chemoembolization(TACE) is recommended as the standard care for unresectable hepatocellular carcinoma(HCC) at Barcelona Clinic Liver Cancer(BCLC) stage A-B. However, the efficacy of TACE on large(> 10 cm) stage A-B HCC is far from satisfactory, and it is proposed that hepatic artery infusion chemotherapy(HAIC)might be a better first-line treatment of this disease. Hence, we compared the safety and efficacy of HAIC with the modified FOLFOX(mFOLFOX) regimen and those ofTACE in patients with massive unresectable HCC.Methods: A prospective, non-randomized, phase II study was conducted on patients with massive unresectable HCC. The protocol involved HAIC with the mFOLFOX regimen(oxaliplatin, 85 mg/m^2 intra-arterial infusion; leucovorin,400 mg/m^2 intra-arterial infusion; and fluorouracil, 400 mg/m2 bolus infusion and 2400 mg/m^2 continuous infusion)every 3 weeks and TACE with 50 mg of epirubicin, 50 mg of lobaplatin, 6 mg of mitomycin, and lipiodol and polyvinyl alcohol particles. The tumor responses, time-to-progression(TTP), and safety were assessed.Results: A total of 79 patients were recruited for this study: 38 in the HAIC group and 41 in the TACE group. The HAIC group exhibited higher partial response and disease control rates than did the TACE group(52.6% vs. 9.8%, P < 0.001;83.8% vs. 52.5%, P = 0.004). The median TTPs for the HAIC and TACE groups were 5.87 and 3.6 months(hazard radio[HR] = 2.35,95% confidence interval [CI] = 1.16-4.76, P = 0.015). More patients in the HAIC group than in the TACE group underwent resection(10 vs. 3,P = 0.033). The proportions of grade 3-4 adverse events(AE) and serious adverse events(SAE) were lower in the HAIC group than in the TACE group(grade 3-4 AEs: 13 vs. 27, P = 0.007;SAEs: 6 vs. 15,p = 0.044). More patients in the TACE group than in the HAIC group had the study treatment terminated early due to intolerable treatment-related adverse events or the withdrawal of consent(10 vs. 2,P = 0.026).Conclusions: HAIC with mFOLFOX yielded significantly bette 展开更多
关键词 HEPATOCELLULAR carcinoma Hepatic ARTERY INFUSION chemotherapy Transarterial CHEMOEMBOLIZATION mFOLFOX
下载PDF
全球能源互联网中的储能技术及应用 被引量:33
3
作者 李建林 孟高军 +3 位作者 葛乐 周京华 石文辉 张占奎 《电器与能效管理技术》 2020年第1期1-8,共8页
构建能源互联网是实现能源合理配置和资源可持续发展的重要途径,储能技术是能源互联网建设中的关键一环。针对全球能源互联网中的储能技术及其应用,首先介绍了储能技术的类型与特性,并阐述了能源互联网中各个环节储能发展的必要性以及... 构建能源互联网是实现能源合理配置和资源可持续发展的重要途径,储能技术是能源互联网建设中的关键一环。针对全球能源互联网中的储能技术及其应用,首先介绍了储能技术的类型与特性,并阐述了能源互联网中各个环节储能发展的必要性以及当前全球储能发展现状。重点梳理了当前典型国家与地区的储能市场发展状况,并分析了政策对当地储能产业发展的贡献与启示。然后根据全球能源互联网结构框架,针对源、网、荷等环节给出储能技术配置规划方案。最后结合当前典型地区能源发展需求、政策导向因素,对未来储能产业的发展进行预测与展望。 展开更多
关键词 能源互联网 储能 配置方案 政策
下载PDF
Expenditure and financial burden for the diagnosis and treatment of colorectal cancer in China:a hospital.based,multicenter,cross-sectional survey 被引量:29
4
作者 Hui-Yao Huang Ju-Fang shi +28 位作者 Lan-Wei Guo Ya-Na Bai Xian-Zhen Liao Guo-iangLiu A-Yan Mao Jian-Song Ren Xiao-Jie Sun Xin-Yu Zhu le Wang Bing-Bing Song Ling-Bin Du Lin Zhu Ji-Yong Gong Qi Zhou Yu-Qin Liu Rong Cao Ling Mai Li Lan Xiao-Hua Sun Ying Ren Jin-Yi Zhou Yuan-Zheng Wang Xiao Qi Pei-An Lou Dian shi Ni Li Kai Zhang Jie He Min Dai 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第8期352-366,共15页
Background: The increasing prevalence of colorectal cancer(CRC) in China and the paucity of information about relevant expenditure highlight the necessity of better understanding the financial burden and effect of CRC... Background: The increasing prevalence of colorectal cancer(CRC) in China and the paucity of information about relevant expenditure highlight the necessity of better understanding the financial burden and effect of CRC diagnosis and treatment. We performed a survey to quantify the direct medical and non-medical expenditure as well as the resulting financial burden of CRC patients in China.Methods: We conducted a multicenter, cross-sectional survey in 37 tertiary hospitals in 13 provinces across China between 2012 and 2014. Each enrolled patient was interviewed using a structured questionnaire. All expenditure data were inflated to the 2014 Chinese Yuan(CNY; 1 CNY = 0.163 USD). We quantified the overall expenditure and financial burden and by subgroup(hospital type, age at diagnosis, sex, education, occupation, insurance type, household income, clinical stage, pathologic type, and therapeutic regimen). We then performed generalized linear modeling to determine the factors associated with overall expenditure.Results: A total of 2356 patients with a mean age of 57.4 years were included, 57.1 % of whom were men; 13.9% of patients had stage I cancer; and the average previous-year household income was 54,525 CNY.The overall average direct expenditure per patient was estimated to be 67,408 CNY, and the expenditures for stage Ⅰ, Ⅱ, Ⅲ, and Ⅳ disease were 56,099 CNY, 59,952 CNY, 67,292 CNY, and 82,729 CNY, respectively. Non-medical expenditure accounted for 8.3%of the overall expenditure. The 1-year out-of-pocket expenditure of a newly diagnosed patient was 32,649 CNY, which accounted for 59.9% of their previous-year household income and caused 75.0% of families to suffer an unmanageable financial burden. Univariate analysis showed that financial burden and overall expenditure differed in almost all subgroups(P < 0.05), except for sex. Multivariate analysis showed that patients who were treated in specialized hospitals and those who were diagnosed with adenocarcinoma or diagnosed at a later stage were likely to spen 展开更多
关键词 COLORECTAL NEOPLASMS Direct EXPENDITURE FINANCIAL BURDEN China
下载PDF
颗粒离散元法工程应用的三大问题探讨 被引量:29
5
作者 刘春 乐天呈 +1 位作者 施斌 朱遥 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2020年第6期1142-1152,共11页
颗粒离散元法常用于岩土试样的宏微观特性研究。在模拟工程问题时,需要用较大的单元来代表岩土块体,并赋以相应的力学性质。颗粒离散元法的工程应用面临着三大问题:(1)难以直接得到特定力学性质的堆积模型,其建模困难;(2)计算量巨大,限... 颗粒离散元法常用于岩土试样的宏微观特性研究。在模拟工程问题时,需要用较大的单元来代表岩土块体,并赋以相应的力学性质。颗粒离散元法的工程应用面临着三大问题:(1)难以直接得到特定力学性质的堆积模型,其建模困难;(2)计算量巨大,限制了大规模工程应用;(3)多场和流固耦合理论以及软件还不完善。在分析这些问题本质和研究进展的基础上,提出宏微观转换公式和自动训练方法来快速建模;基于矩阵离散元计算法来实现高性能的数值计算;引入孔隙密度流法以实现快速的多场和流固耦合模拟。基于这些解决思路,从零开始研发了高性能离散元软件MatDEM,实现了综合大变形、多场和流固耦合数值模拟。最后,探讨了亟待解决的关键科学和技术问题。 展开更多
关键词 岩土工程 离散元 工程应用 MatDEM
原文传递
Effect of Intravenous Administration of Liposomal Prostaglandin E1 on Microcirculation in Patients with ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Intervention 被引量:27
6
作者 Li-Ye Wei Xiang-Hua Fu +4 位作者 Wei Li Xi-le Bi shi-Ru Bai Kun Xing Yan-Bo Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第9期1147-1150,共4页
Background:Several studies have demonstrated that primary percutaneous coronary intervention (PCI) can result in reperfusion injury.This study aims to investigate the effectiveness of liposomal prostaglandin E l (... Background:Several studies have demonstrated that primary percutaneous coronary intervention (PCI) can result in reperfusion injury.This study aims to investigate the effectiveness of liposomal prostaglandin E l (Lipo-PGE1,Alprostadil,Beijing Tide Pharmaceutical Co.,Ltd.) for enhancing microcirculation in reperfusion injury.In addition,this study determined the optimal administration method for acute ST elevation myocardial infarction (STEMI) patients undergoing primary PCI.Methods:Totally,68 patients with STEMI were randomly assigned to two groups:intravenous administration ofLipo-PGE 1 (Group A),and no Lipo-PGE1 administration (Group B).The corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC) and myocardial blush grade (MBG) were calculated.Patients were followed up for 6 months.Major adverse cardiac events (MACE) were also measured.Results:There was no significant difference in the baseline characteristics between the two groups.The cTFC parameter in Group A was significantly lower than Group B (18.06 ± 2.06 vs.25.31 ± 2.59,P < 0.01).The ratio of final MBG grade-3 was significantly higher (P < 0.05) in Group A (87.9%) relative to Group B (65.7%).There was no significant difference between the two groups in final TIMI-3 flow and no-reflow.Patients were followed up for 6 months,and the occurrence of MACE in Group A was significantly lower than that in Group B (6.1% vs.25.9% respectively,P < 0.05).Conclusions:Myocardial microcirculation of reperfusion injury in patients with STEMI,after primary PCI,can be improved by administering Lipo-PGE1. 展开更多
关键词 Intravenous Administration Liposomal Prostaglandin E l Primary Percutaneous Coronary Intervention ST Elevation Myocardial Infarction
原文传递
Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis:a case-control study 被引量:25
7
作者 Zhen-Yu Liu,Yan-Ming Zhou,le-Hua shi and Zheng-Feng YinAuthor Affiliations:Molecular Oncology Laboratory and Department of Comprehensive Treatment I,Eastern Hepatobiliary Surgery Hospital,Second Military Medical University,Shanghai 200438,China Department of Hepato-Biliary-Pancreato-Vascular Surgery,First Affiliated Hospital,Xiamen University,Xiamen 361003,China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2011年第6期626-631,共6页
BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the develop... BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the development of ICC in patients with hepatolithiasis in China.METHODS:Eighty-seven patients with pathologically diagnosed hepatolithiasis associated with ICC and 228 with hepatolithiasis alone matched by sex,age (±2 years),hospital admittance and place of residence were interviewed during the period of 2000-2008.Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each risk factor.RESULTS:Among the patients with hepatolithiasis associated with ICC,the mean age was 57.7 years and 61.0% were female Univariate analysis showed that the significant risk factors for ICC development in hepatolithiasis were smoking,family history of cancer,appendectomy during childhood (under age 20),and duration of symptoms >10 years.In multivariate stepwise logistic regression analysis,smoking (OR=1.931,95% CI:1.000-3.731),family history of cancer (OR=5.175,95% CI:1.216-22.022),and duration of symptoms >10 years (OR=2.348 95% CI:1.394-3.952) were independent factors.CONCLUSION:Smoking,family history of cancer and duration of symptoms >10 years may be risk factors for ICC in patients with hepatolithiasis. 展开更多
关键词 risk factors intrahepatic cholangiocarcinoma HEPATOLITHIASIS case-control study
下载PDF
超声引导前路坐骨神经和股神经阻滞在膝关节以下骨折手术中的应用 被引量:22
8
作者 王权光 陈丽梅 +3 位作者 刘乐 施克俭 张学政 徐旭仲 《温州医科大学学报》 CAS 2016年第11期818-821,825,共5页
目的:观察超声引导下前路坐骨神经和股神经阻滞用于单侧膝关节以下骨折患者的手术麻醉和术后镇痛的临床效果,并与硬膜外阻滞麻醉进行比较。方法:择期行单侧下肢骨折手术患者60例,随机分为超声引导下前路坐骨神经和股神经阻滞组(A组)和... 目的:观察超声引导下前路坐骨神经和股神经阻滞用于单侧膝关节以下骨折患者的手术麻醉和术后镇痛的临床效果,并与硬膜外阻滞麻醉进行比较。方法:择期行单侧下肢骨折手术患者60例,随机分为超声引导下前路坐骨神经和股神经阻滞组(A组)和硬膜外阻滞组(B组),每组30例。B组患者术后单次硬膜外注射2 mg吗啡进行术后镇痛。记录2组患者感觉神经阻滞起效时间、持续时间及操作时间;用视觉模拟评分法记录麻醉操作体位摆放、术后48 h疼痛强度、监测麻醉期间平均动脉压(MAP)、心率(HR)变化;记录患者术后首次进食的时间,术后24 h内出现并发症及患者总体满意度。结果:A组的术后镇痛维持时间长,明显减少麻醉操作时体位变动的疼痛。B组麻醉后15、30、45 min MAP显著低于麻醉前和A组(P<0.01)。A组术后并发症发生率显著低于B组(P<0.05),术后开始进食时间显著短于B组(P<0.001),有更高的患者总体满意度。结论:单侧下肢骨折手术采用超声引导下前路坐骨神经和股神经阻滞可以提供完善的术中、术后镇痛,并且并发症少,提高了患者总体满意度。 展开更多
关键词 超声 坐骨神经 股神经 阻滞
下载PDF
GC-IMS结合化学计量学分析8个产区香椿挥发性成分差异 被引量:20
9
作者 张乐 张雅 +4 位作者 史冠莹 赵丽丽 蒋鹏飞 王旭增 王赵改 《食品科学》 EI CAS CSCD 北大核心 2022年第22期301-308,共8页
采用气相色谱-离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术研究8个产区香椿挥发性成分差异。共鉴定出56种化合物,醇类和醛类的相对含量较高。基于化学计量学主成分分析和偏最小二乘判别分析(partial least sq... 采用气相色谱-离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术研究8个产区香椿挥发性成分差异。共鉴定出56种化合物,醇类和醛类的相对含量较高。基于化学计量学主成分分析和偏最小二乘判别分析(partial least squares-discriminant analysis,PLS-DA)可以很好区分8个产区香椿样品。基于PLS-DA模型的变量投影重要性(variable importance in projection,VIP)得分对8个产区香椿挥发性有机化合物进行判别分析,筛选出12种(VIP>1)标志挥发性化合物,其中(E)-2-己烯醛-D、乙酸乙酯-D、苯酚、糠醛、苯乙醇是主要的差异代谢物。不同产区香椿挥发性化合物存在较大差异。GC-IMS可以实现对不同产区香椿挥发性化合物的差异化快速分析,为香椿挥发性香气差异研究提供有益依据。 展开更多
关键词 香椿 挥发性化合物 气相色谱-离子迁移谱 主成分分析 偏最小二乘判别分析
下载PDF
Approaches being used in the national schistosomiasis elimination programme in China:a review 被引量:18
10
作者 le-Ping Sun Wei Wang +4 位作者 Qing-Biao Hong shi-Zhu Li You-Sheng Liang Hai-Tao Yang Xiao-Nong Zhou 《Infectious Diseases of Poverty》 SCIE 2017年第1期475-483,共9页
Schistosomiasis japonica,caused by the human blood fluke Schistosoma japonicum,remains a major public health problem in China,although great success has been achieved.The control efforts during the past half-decade,no... Schistosomiasis japonica,caused by the human blood fluke Schistosoma japonicum,remains a major public health problem in China,although great success has been achieved.The control efforts during the past half-decade,notably the wide implementation of the new integrated strategy with emphasis on control of the source of S.japonicum infection across the country since 2004,has greatly reduced S.japonicum in humans,livestock,and intermediate host Oncomelania hupensis snails,and transmission control of schistosomiasis was achieved in China in 2015.A two-stage roadmap was therefore proposed for schistosomiasis elimination in 2015,with aims to achieve transmission interruption by 2020 and achieve disease elimination by 2025 in the country.During the last two decades,a variety of approaches,which target the epidemiological factors of schistosomiasis japonica have been developed,in order to block the transmission cycle of the parasite.These approaches have been employed in the national or local schistosomiasis control activities,and facilitated,at least in part,the progress of the schistosomiasis elimination programs.Here,we present an approach to control the source of S.japonicum infection,three new tools for snail control,three approaches for detecting and monitoring S.japonicum infection,and a novel model for health education.These approaches are considered to play a great role in the stage moving towards transmission interruption and elimination of schistosomiasis in China. 展开更多
关键词 Schistosomiasis japonica Schistosoma japonicum Oncomelania hupensis ELIMINATION Snail control Source of infection Health education China
原文传递
Down-regulation of miR-622 in gastric cancer promotes cellular invasion and tumor metastasis by targeting ING1 gene 被引量:16
11
作者 Xiao-Bo Guo Chang-Qing Jing le-Ping Li Li Zhang Yu- Long shi Jin-Shen Wang Jing-lei Liu Chen-Sheng Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第14期1895-1902,共8页
AIM:To evaluate the biological and clinical characteristics of miR-622 in gastric cancer. METHODS:We analyzed the expression of miR-622 in 57 pair matched gastric neoplastic and adjacent non-neoplastic tissues by quan... AIM:To evaluate the biological and clinical characteristics of miR-622 in gastric cancer. METHODS:We analyzed the expression of miR-622 in 57 pair matched gastric neoplastic and adjacent non-neoplastic tissues by quantitative real-time polymerase chain reaction. Functional analysis of miR-622 expression was assessed in vitro in gastric cancer cell lines with miR-622 precursor and inhibitor. The roles of miR-622 in tumorigenesis and tumor metastasis were analyzed using a stable miR-622 expression plasmid in nude mice. A luciferase reporter assay was used to assess the effect of miR-622 on inhibitor of growth family,member 1 (ING1) expression. RESULTS:Expression of miR-622 was down-regulated in gastric cancer. MiR-622 was found involved in differentia-tion and lymphatic metastasis in human gastric cancer. Ectopic expression of miR-622 promoted invasion,tumorigenesis and metastasis of gastric cancer cells both in vitro and in vivo. ING1 is a direct target of miR-622. CONCLUSION:These findings help clarify the molecular mechanisms involved in gastric cancer metastasis and indicate that miR-622 modulation may be a bona fide treatment of gastric cancer. 展开更多
关键词 MicroRNA MiR-622 Gastric cancer METASTASIS Inhibitor of growth family member 1
下载PDF
上海市中心城区社区医疗机构肿瘤安宁疗护资源使用状况调查及医护人员职业满意度分析 被引量:16
12
作者 杨森 赵华新 +7 位作者 牛晓敏 陈晨 张文静 葛许华 陆媛 马乐 史晓晓 于德华 《中国全科医学》 CAS 北大核心 2021年第12期1541-1545,共5页
背景上海安宁疗护服务已走过30余年的历程,目前上海全市246家社区卫生服务中心已全部开展安宁疗护服务,经过多年的发展,上海积极推进试点、制订服务规范、实施能力培训等措施,有力推动了安宁疗护持续、规范、高效发展。目的了解上海市... 背景上海安宁疗护服务已走过30余年的历程,目前上海全市246家社区卫生服务中心已全部开展安宁疗护服务,经过多年的发展,上海积极推进试点、制订服务规范、实施能力培训等措施,有力推动了安宁疗护持续、规范、高效发展。目的了解上海市中心城区社区医疗机构肿瘤安宁疗护资源使用状况及从业医护人员的满意度情况。方法2019年3—9月采用单纯随机抽样法分别从上海市7个中心城区(黄浦区、徐汇区、杨浦区、普陀区、静安区、长宁区、虹口区)的14家试点安宁疗护社区卫生服务中心选取安宁疗护从业医护人员42名为研究对象。分析试点机构2018年卫生统计报表和财务报表(安宁疗护病床使用率、安宁疗护时间、安宁疗护中心人均医疗费用、安宁疗护中心日均医疗费用)。并采用自行设计的《上海市安宁疗护试点机构医护人员从业满意度调查问卷》对医护人员从业满意度进行调查与访谈,具体内容包括受访者的基本信息、从业满意度(薪资福利、职业发展、职业认同感、离职意向、同行关系、工作满意度)以及影响安宁疗护从业医护人员职业满意度的因素。结果2018年上海市中心城区试点安宁疗护机构的安宁疗护病床使用率为(48.42±2.34)%;平均住院时间为(41.8±3.5)d,人均医疗费用为(7632.8±234.7)元,日均医疗费用为(182.6±22.6)元;居家安宁疗护平均时间为(56.2±7.5)d,人均医疗费用为(1371.3±186.4)元,日均医疗费用为(24.4±4.2)元。社区医疗机构安宁疗护从业医护人员对薪资福利、职业发展的满意度偏低,对同行关系和职业认同感的满意度偏高。安宁疗护从业医护人员对居家安宁疗护和机构安宁疗护的工作满意度结果相似。影响安宁疗护从业医护人员开展机构安宁疗护服务的主要因素是:"待遇较低、工作量大,付出与收获不成比例""依靠机构自身运营补贴,专项经 展开更多
关键词 临终医护 安宁疗护 社区卫生服务中心 恶性肿瘤 采访(主题) 满意度
下载PDF
基于多源遥感的红树林监测 被引量:15
13
作者 王乐 时晨 +8 位作者 田金炎 宋晓楠 贾明明 李小娟 刘晓萌 钟若飞 殷大萌 杨杉杉 郭先仙 《生物多样性》 CAS CSCD 北大核心 2018年第8期838-849,共12页
红树林是生长在热带以及亚热带海岸潮间带上的生态群落,其生产力高,固碳能力强,对保持海岸带生物多样性具有十分重要的价值。本文介绍了利用多源遥感数据监测红树林的一些主要研究内容,分为3个方面:(1)在时空模式研究方面,利用高空间分... 红树林是生长在热带以及亚热带海岸潮间带上的生态群落,其生产力高,固碳能力强,对保持海岸带生物多样性具有十分重要的价值。本文介绍了利用多源遥感数据监测红树林的一些主要研究内容,分为3个方面:(1)在时空模式研究方面,利用高空间分辨率影像像素和对象结合的方法对红树林树种进行分类以及利用Landsat影像对红树林进行动态变化监测并分析其驱动因素;(2)在结构参数研究方面,利用无人机多光谱数据及地面激光雷达数据对红树林叶面积指数进行反演;(3)在生理生化参数研究方面,探讨了红树林叶绿素含量对淹没状况的响应、互花米草(Spartina alterniflora)入侵是否影响红树林光能利用率,以及光化学反射指数(photochemical reflectance index,PRI)与光能利用率(light use efficiency,LUE)的关系。上述系列研究为提取红树林相关信息要素时如何选择合适的分析方法提供了有力的参考,强调了遥感在研究红树林时空模式,提取结构参数和生物生化参数监测的有效性,从而更好地促进红树林生态系统的生物多样性保育工作。 展开更多
关键词 红树林 生物多样性 多源遥感 树种分类 入侵物种
原文传递
新型板栗饮料稳定性研究 被引量:13
14
作者 万景瑞 张乐 +5 位作者 王赵改 史冠莹 王晓敏 程菁菁 蒋鹏飞 赵丽丽 《食品与发酵工业》 CAS CSCD 北大核心 2019年第14期158-162,共5页
为了解决新型板栗饮料在加工过程中易出现沉淀的问题,寻找最适合板栗饮料稳定所需要的稳定剂和乳化剂。研究了黄原胶、羧甲基纤维素钠(carboxymethylcellulose sodium,CMC)、单硬脂肪酸甘油酯、脂肪酸蔗糖酯、海藻酸丙二醇酯(propylene ... 为了解决新型板栗饮料在加工过程中易出现沉淀的问题,寻找最适合板栗饮料稳定所需要的稳定剂和乳化剂。研究了黄原胶、羧甲基纤维素钠(carboxymethylcellulose sodium,CMC)、单硬脂肪酸甘油酯、脂肪酸蔗糖酯、海藻酸丙二醇酯(propylene glycol alginate,PGA)等稳定剂和乳化剂对新型板栗饮料稳定性的影响。在单因素实验的基础上以黄原胶、CMC、PGA和单硬脂肪酸甘油酯为影响因素进行正交实验,得出最佳复合稳定剂质量浓度为:黄原胶1 g/L,CMC 4 g/L,PGA 2 g/L,单硬脂肪酸甘油酯1 g/L,新型板栗饮料稳定性达到71.107%,根据极差分析得出影响板栗饮料稳定性的因子主次顺序依次为黄原胶>PGA>CMC>单硬脂肪酸甘油酯。该研究为解决板栗饮料加工过程中的稳定性问题提供理论依据。 展开更多
关键词 板栗饮料 稳定性 正交试验 最佳添加量
下载PDF
加味茵陈蒿汤联合熊去氧胆酸治疗原发性胆汁性胆管炎的临床疗效及对FGF19的影响 被引量:13
15
作者 凌琪华 郑月琪 +6 位作者 陈建杰 乐敏 时桢 徐黎 陈逸云 卓蕴慧 商斌仪 《上海中医药杂志》 2020年第S01期41-43,共3页
目的评价加味茵陈蒿汤联合熊去氧胆酸治疗原发性胆汁性胆管炎的临床疗效及对血清FGF19的影响。方法将64例肝胆湿热兼瘀血阻络型原发性胆汁性胆管炎患者随机分为治疗组和对照组,每组32例。治疗组给予加味茵陈蒿汤联合熊去氧胆酸治疗,对... 目的评价加味茵陈蒿汤联合熊去氧胆酸治疗原发性胆汁性胆管炎的临床疗效及对血清FGF19的影响。方法将64例肝胆湿热兼瘀血阻络型原发性胆汁性胆管炎患者随机分为治疗组和对照组,每组32例。治疗组给予加味茵陈蒿汤联合熊去氧胆酸治疗,对照组给予熊去氧胆酸治疗。两组疗程均为12个月,观察中医证候积分、生化学应答率、肝脏生化指标、血清FGF19的变化情况。结果①治疗后,治疗组、对照组的生化学应答率分别为87.5%、62.5%,组间差异有统计学意义(P<0.05);②治疗后,治疗组血清ALT、AST、GGT、ALP水平均较对照组下降,差异有统计学意义(P<0.05);③治疗后,治疗组中医证候积分低于对照组,差异有统计学意义(P<0.05);④治疗后,治疗组血清FGF19水平较对照组升高,差异有统计学意义(P<0.05)。结论加味茵陈蒿汤联合熊去氧胆酸治疗肝胆湿热兼瘀血阻络型原发性胆汁性胆管炎,能够有效提高生化学应答率,可改善血清ALT、AST、GGT、ALP水平及中医证候积分,提高血清FGF19水平。 展开更多
关键词 原发性胆汁性胆管炎 中西医结合疗法 加味茵陈蒿汤 熊去氧胆酸 成纤维细胞生长因子19
下载PDF
Ca_(1−x)Li_(x)Al_(1−x)Si_(1+x)N_(3):Eu^(2+) solid solutions as broadband,color-tunable and thermally robust red phosphors for superior color rendition white light-emitting diodes 被引量:12
16
作者 le Wang Rong-Jun Xie +7 位作者 Yuanqiang Li Xiaojun Wang Chong-Geng Ma Dong Luo Takashi Takeda Yi-Ting Tsai Ru-shi Liu Naoto Hirosaki 《Light(Science & Applications)》 SCIE EI CAS CSCD 2016年第1期465-473,共9页
Color rendition,luminous efficacy and reliability are three key technical parameters for white light-emitting diodes(wLEDs)that are dominantly determined by down-conversion phosphors.However,there is usually an inevit... Color rendition,luminous efficacy and reliability are three key technical parameters for white light-emitting diodes(wLEDs)that are dominantly determined by down-conversion phosphors.However,there is usually an inevitable trade-off between color rendition and luminescence efficacy because the spectrum of red phosphor(that is,spectral broadness and position)cannot satisfy them simultaneously.In this work,we report a very promising red phosphor that can minimize the aforementioned trade-off via structure and band-gap engineering,achieved by introducing isostructural LiSi_(2)N_(3) into CaAlSiN_(3):Eu^(2+).The solid solution phosphors show both substantial spectra broadening(88→117 nm)and blueshift(652→642 nm),along with a significant improvement in thermal quenching(only a 6%reduction at 150℃),which are strongly associated with electronic and crystal structure evolutions.The broadband and robust red phosphor thus enables fabrication of super-high color rendering wLEDs(Ra=95 and R9=96)concurrently with the maintenance of a high-luminous efficacy(101 lm W^(−1)),validating its superiority in highperformance solid state lightings over currently used red phosphors. 展开更多
关键词 color rendering LEDS NITRIDE PHOSPHOR structure disorder
原文传递
Effective exposure of nitrogen heteroatoms in 3D porous graphene framework for oxygen reduction reaction and lithium–sulfur batteries 被引量:12
17
作者 Jia-le shi Cheng Tang +2 位作者 Jia-Qi Huang Wancheng Zhu Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第1期167-175,共9页
The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,mo... The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,most of nitrogen heteroatoms are doped into the bulk phase of carbon without site selectivity, which significantly reduces the contacts of feedstocks with the active dopants in a conductive scaffold. Herein we proposed the chemical vapor deposition of a nitrogen-doped graphene skin on the 3D porous graphene framework and donated the carbon/carbon composite as surface N-doped grapheme(SNG). In contrast with routine N-doped graphene framework(NGF) with bulk distribution of N heteroatoms, the SNG renders a high surface N content of 1.81 at%, enhanced electrical conductivity of 31 S cm^(-1), a large surface area of 1531 m^2 g^(-1), a low defect density with a low I_D/I_G ratio of 1.55 calculated from Raman spectrum, and a high oxidation peak of 532.7 ℃ in oxygen atmosphere. The selective distribution of N heteroatoms on the surface of SNG affords the effective exposure of active sites at the interfaces of the electrode/electrolyte, so that more N heteroatoms are able to contact with oxygen feedstocks in oxygen reduction reaction or serve as polysulfide anchoring sites to retard the shuttle of polysulfides in a lithium–sulfur battery. This work opens a fresh viewpoint on the manipulation of active site distribution in a conductive scaffolds for multi-electron redox reaction based energy conversion and storage. 展开更多
关键词 Nitrogen-doped graphene Chemical vapor deposition Oxygen reduction reaction Lithium-sulfur battery Porous carbon materials Exposure of active sites
下载PDF
A human circulating immune cell landscape in aging and COVID-19 被引量:12
18
作者 Yingfeng Zheng Xiuxing Liu +19 位作者 Wenqing le Lihui Xie He Li Wen Wen Si Wang Shuai Ma Zhaohao Huang Jinguo Ye Wen shi Yanxia Ye Zunpeng Liu Moshi Song Weiqi Zhang Jing-Dong J.Han Juan Carlos lzpisua Belmonte Chuanle Xiao Jing Qu Hongyang Wang Guang-Hui Liu Wenru Su 《Protein & Cell》 SCIE CAS CSCD 2020年第10期740-770,共31页
Age-associated changes in immune cells have been linked to an increased risk for infection.However,a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking.... Age-associated changes in immune cells have been linked to an increased risk for infection.However,a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking.Here,we combined scRNA-seq,mass cytometry and sCATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19.We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector,cytotoxic,exhausted and reg-ulatory cells,along with increased late natural killer cells,age-associated B cells,inflammatory monocytes and age-associated dendritic cells.In addition,the expression of genes,which were implicated in coron-avirus susceptibility,was upregulated in a cell subtype-specific manner with age.Notably,COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senes-cence.Therefore,these findings suggest that a dysreg-ulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly. 展开更多
关键词 AGING single-cell sequencing BLOOD COVID-19 immune cells
原文传递
Climate effects of the GlobeLand30 land cover dataset on the Beijing Climate Center climate model simulations 被引量:9
19
作者 shi XueLi NIE SuPing +1 位作者 JU WeiMin YU le 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第9期1754-1764,共11页
Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. I... Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution(30 m) global land cover dataset(Globe Land30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model(BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the Globe Land30 data in the model. First, the Globe Land30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type(PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution Globe Land30 land cover type and area percentage with the coarser model grid resolutions globally. The Globe Land30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies(lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the Globe Land30-based data were used in the BCC_CSM atmosphere model. The results suggest that the Globe Land30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations. 展开更多
关键词 Land cover Climate model Application strategy Numerical simulation Air temperature PRECIPITATION
原文传递
A phase I study of different doses and frequencies of pegylated recombinant human granulocyte-colony stimulating factor(PEG rhG-CSF) in patients with standard-dose chemotherapy-induced neutropenia 被引量:11
20
作者 Yan Qin Xiaohong Han +7 位作者 Lin Wang Ping Du Jiarui Yao Di Wu Yuanyuan Song Shuxiang Zhang le Tang Yuankai shi 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第5期402-410,共9页
Objective: The recommended dose of prophylactic pegylated recombinant human granulocyte-colony stimulating factor(PEG rhG-CSF) is 100 μg/kg once per cycle for patients receiving intense-dose chemotherapy.However, ... Objective: The recommended dose of prophylactic pegylated recombinant human granulocyte-colony stimulating factor(PEG rhG-CSF) is 100 μg/kg once per cycle for patients receiving intense-dose chemotherapy.However, few data are available on the proper dose for patients receiving less-intense chemotherapy. The aim of this phase I study is to explore the proper dose and administration schedule of PEG rhG-CSF for patients receiving standard-dose chemotherapy.Methods:Eligible patients received 3-cycle chemotherapy every 3 weeks.No PEG rhG-CSF was given in the first cycle.Patients experienced grade 3 or 4 neutropenia would then enter the cycle 2 and 3.In cycle 2,patients received a single subcutaneous injection of prophylactic PEG rhG-CSF on d 3,and received half-dose subcutaneous injection in cycle 3 on d 3 and d 5,respectively.Escalating doses(30,60,100 and 200μg/kg)of PEG rhG-CSF were investigated.Results:A total of 26 patients were enrolled and received chemotherapy,in which 24 and 18 patients entered cycle 2 and cycle 3 treatment,respectively.In cycle 2,the incidence of grade 3 or 4 neutropenia for patients receiving single-dose PEG rhG-CSF of 30,60,100 and 200 μg/kg was 66.67%,33.33%,22.22% and 0,respectively,with a median duration less than 1(0–2)d.No grade 3 or higher neutropenia was noted in cycle 3 in all dose cohorts.Conclusions:The pharmacokinetic and pharmacodynamic profiles of PEG rhG-CSF used in cancer patients were similar to those reported,as well as the safety.Double half dose administration model showed better efficacy result than a single dose model in terms of grade 3 neutropenia and above.The single dose of 60 μg/kg,100 μg/kg and double half dose of 30 μg/kg were recommended to the phase Ⅱ study,hoping to find a preferable method for neutropenia treatment. 展开更多
关键词 Phase study chemotherapy dose-finding neutropenia PEG rhG-CSF
下载PDF
上一页 1 2 53 下一页 到第
使用帮助 返回顶部