期刊文献+
共找到563篇文章
< 1 2 29 >
每页显示 20 50 100
The second natural gas hydrate production test in the South China Sea 被引量:41
1
作者 Jian-liang Ye Xu-wen Qin +24 位作者 Wen-wei Xie Hai-long Lu Bao-jin Ma Hai-jun Qiu Jin-qiang Liang Jing-an Lu Zeng-gui Kuang Cheng Lu Qian-yong Liang Shi-peng Wei Yan-jiang Yu Chunsheng Liu Bin Li Kai-xiang Shen Hao-xian Shi Qiu-ping Lu Jing Li Bei-bei Kou Gang Song Bo Li He-en Zhang Hong-feng Lu Chao Ma Yi-fei dong Hang bian 《China Geology》 2020年第2期197-209,共13页
Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitabl... Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017.Based on the understanding of the first production test,the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment,numerical and experimental simulation,and onshore testing of the reservoirs.After that,it conducted the second offshore NGH production test in 1225 m deep Shenhu Area,South China Sea(also referred to as the second production test)from October 2019 to April 2020.During the second production test,a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met,including wellhead stability,directional drilling of a horizontal well,reservoir stimulation and sand control,and accurate depressurization.As a result,30 days of continuous gas production was achieved,with a cumulative gas production of 86.14×104 m3.Thus,the average daily gas production is 2.87×10^4 m^3,which is 5.57 times as much as that obtained in the first production test.Therefore,both the cumulative gas production and the daily gas production were highly improved compared to the first production test.As indicated by the monitoring results of the second production test,there was no anomaly in methane content in the seafloor,seawater,and atmosphere throughout the whole production test.This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs.The industrialization of hydrates consists of five stages in general,namely theoretical research and simulation experiments,exploratory production test,experimental production test,productive production test,and commercial production.The second production test serves as an important step from the exploratory production test to exper 展开更多
关键词 Natural gas hydrates Second production test Horizontal well Reservoir stimulation Environmental impact NGH exploration trial engineering South China Sea
下载PDF
系统评价报告规范:PRISMA 2020与PRISMA 2009的对比分析与实例解读 被引量:41
2
作者 高亚 刘明 +13 位作者 杨珂璐 葛龙 李伦 李江 孙凤 杨智荣 武珊珊 董圣杰 张天嵩 肖月 吴嘉瑞 张俊华 卞兆祥 田金徽 《中国循证医学杂志》 CSCD 北大核心 2021年第5期606-616,共11页
系统评价/Meta分析报告规范(PRISMA)旨在增加系统评价报告的透明度和提高系统评价的报告质量。PRISMA 2020是对PRISMA 2009的更新和修订,其于2021年3月发表在BMJ杂志。本文对PRISMA 2020与PRISMA 2009条目进行对比分析并结合实例解读,... 系统评价/Meta分析报告规范(PRISMA)旨在增加系统评价报告的透明度和提高系统评价的报告质量。PRISMA 2020是对PRISMA 2009的更新和修订,其于2021年3月发表在BMJ杂志。本文对PRISMA 2020与PRISMA 2009条目进行对比分析并结合实例解读,旨在帮助国内学者更好地理解与应用最新版PRISMA,以期提高系统评价的报告质量。 展开更多
关键词 系统评价 干预 PRISMA 2020 报告规范 解读
原文传递
中国种养业废弃物肥料化利用发展分析 被引量:41
3
作者 田慎重 郭洪海 +5 位作者 姚利 宫志远 董亮 边文范 罗加法 张玉凤 《农业工程学报》 EI CAS CSCD 北大核心 2018年第B11期123-131,共9页
近年来中国种养业发展迅速,随之产生的废弃物数量也呈现大幅度增长,由于人们对种养业废弃物资源的认识不够,特别是将废弃物肥料化利用重视程度不够,造成了资源浪费,加重了环境污染。在国家大力推进"加快废弃物资源化利用"的... 近年来中国种养业发展迅速,随之产生的废弃物数量也呈现大幅度增长,由于人们对种养业废弃物资源的认识不够,特别是将废弃物肥料化利用重视程度不够,造成了资源浪费,加重了环境污染。在国家大力推进"加快废弃物资源化利用"的背景下,该文总结了中国种养业废弃物肥料化利用的现状,概述了废弃物肥料化利用的主要方式和相关技术,分析了中国在种养业废弃物肥料化利用过程中存在的突出问题,提出了相应对策建议,并对未来中国种养业废弃物肥料化利用的发展趋势进行了展望,为中国种养业废弃物资源化利用,特别是肥料化利用的发展提供参考。 展开更多
关键词 废弃物处置 秸秆 废弃物肥料化 废弃物资源化 种养业 研究进展
下载PDF
Extending the CONSORT Statement to moxibustion 被引量:32
4
作者 Chung-wah Cheng Shu-fei Fu +11 位作者 Qing-hui Zhou Tai-xiang Wu Hong-cai Shang Xu-dong Tang Zhi-shun Liu Jia Liu Zhi-xiu Lin Lixing Lao Ai-ping Bo-li Zhang Bao-yan Liu Zhao-xiang bian 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第1期54-63,共10页
The STandards for Reporting Interventions in Clinical Trials Of Moxibustion (STRICTOM), in the form of a checklist and descriptions of checklist items, were designed to improve reporting of moxibustion trials, and t... The STandards for Reporting Interventions in Clinical Trials Of Moxibustion (STRICTOM), in the form of a checklist and descriptions of checklist items, were designed to improve reporting of moxibustion trials, and thereby facilitating their interpretation and replication. The STRICTOM checklist included 7 items and 16 sub-items. These set out reporting guidelines for the moxibustion rationale, details of moxibustion, treatment regimen, other components of treatment, treatment provider background, control and comparator interventions, and precaution measures. In addition, there were descriptions of each item and examples of good reporting. It is intended that the STRICTOM can be used in conjunction with the main CONSORT Statement, extensions for nonpharmacologic treatment and pragmatic trials, and thereby raise the quality of reporting of clinical trials of moxibustion. Further comments will be solicited from the experts of the CONSORT Group, the STRICTA Group, acupuncture and moxibustion societies, and clinical trial authors for optimizing the STRICTOM. 展开更多
关键词 MOXIBUSTION randomized controlled trials GUIDELINES
下载PDF
Effect of preoperative transcatheter arterial chemoembolization on angiogenesis of hepatocellular carcinoma cells 被引量:30
5
作者 En-Hua Xiao dong Guo Du-lun bian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第36期4582-4586,共5页
AIM: To evaluate the effects of four types of preoperative transcatheter arterial chemoembolization (TACE) on angiogenesis of hepatocellular carcinoma (HCC) ceils. METHODS: A total of 136 patients with HCC under... AIM: To evaluate the effects of four types of preoperative transcatheter arterial chemoembolization (TACE) on angiogenesis of hepatocellular carcinoma (HCC) ceils. METHODS: A total of 136 patients with HCC underwent liver resection. One to five courses of TACE prior to liver resection were performed in 79 patients (TACE group), in which one to four courses of chemotherapy alone were performed in 11 patients (group A); one to five courses of chemotherapy combined with iodized oil were performed in 33 patients (group B); one to three courses of chemotherapy combined with iodized oil and gelatin sponge were performed in 23 patients (group C), one to three courses of chemotherapy combined with iodized oil, ethanol and gelatin sponge were performed in 12 patients (group D). The other 57 patients only received liver resection (non-TACE group). The microvessels were marked by CD31. The expression of CD31 and vascular endothelial growth factor (VEGF) protein were detected by immunohistochemical methods. RESULTS: The mean microvessel density (MVD) in HCC cells was significantly higher in groups A, B, C and D than in the nonACE group (P 〈 0.05). The expression of VEGF protein in HCC cells were significantly higher in groups A, B, C and D than in the non-TACE group (P 〈 0.05). MVD and the expression of VEGF protein were positively correlated. Mean MVD and the expression of VEGF protein were closely related to the number of courses of TACE and the interval of TACE. CONCLUSION: Four different types of preoperative TACE regimens enhanced angiogenesis in HCC cells by up-regulating the expression of VEGF protein. It is necessary to repress angiogenesis of liver cancer after TACE. 展开更多
关键词 ANGIOGENESIS Hepatocellular carcinoma IMMUNOHISTOCHEMISTRY Transcatheter arterial chemoembolization Vascular endothelial growth factor
下载PDF
基础教育信息化发展的问题审视与战略调整 被引量:30
6
作者 董玉琦 毕景刚 +2 位作者 钱松岭 边家胜 乔沛昕 《开放教育研究》 CSSCI 北大核心 2021年第4期50-58,共9页
基于"十三五"期间全国教育信息化发展调研、本研究团队近三年开展的区域调研数据和国际比较数据,本研究发现,经过二十多年的探索和发展,我国基础教育信息化取得了举世瞩目的成就,但也存在发展不均衡、应用不充分、政策不落地... 基于"十三五"期间全国教育信息化发展调研、本研究团队近三年开展的区域调研数据和国际比较数据,本研究发现,经过二十多年的探索和发展,我国基础教育信息化取得了举世瞩目的成就,但也存在发展不均衡、应用不充分、政策不落地等问题,问题的根源在于缺乏优质的顶层设计和有效的基础研究。为了推进我国基础教育信息化高质量发展,在"十四五"期间,我们建议对基础教育信息化发展战略作出如下调整:理念上从深度融合转为育人为本、导向上从应用驱动转为改善学习、机制上从独立运作转为协同创新、方略上从各自实践转为研究先行、政策上从以点带面转为依据标准。 展开更多
关键词 教育信息化 教育现代化 基础教育 国际比较
下载PDF
Impact of psychological stress on irritable bowel syndrome 被引量:30
7
作者 Hong-Yan Qin Chung-Wah Cheng +1 位作者 Xu-dong Tang Zhao-Xiang bian 《World Journal of Gastroenterology》 SCIE CAS 2014年第39期14126-14131,共6页
Psychological stress is an important factor for the development of irritable bowel syndrome(IBS). More and more clinical and experimental evidence showed that IBS is a combination of irritable bowel and irritable brai... Psychological stress is an important factor for the development of irritable bowel syndrome(IBS). More and more clinical and experimental evidence showed that IBS is a combination of irritable bowel and irritable brain. In the present review we discuss the potential role of psychological stress in the pathogenesis of IBS and provide comprehensive approaches in clinical treatment. Evidence from clinical and experimental studies showed that psychological stresses have marked impact on intestinal sensitivity, motility, secretion and permeability, and the underlying mechanism has a close correlation with mucosal immune activation, alterations in central nervous system, peripheral neurons and gastrointestinal microbiota. Stress-induced alterations in neuro-endocrine-immune pathways acts on the gut-brain axis and microbiota-gut-brain axis, and cause symptom flare-ups or exaggeration in IBS. IBS is a stresssensitive disorder, therefore, the treatment of IBS should focus on managing stress and stress-induced responses. Now, non-pharmacological approaches and pharmacological strategies that target on stress-related alterations, such as antidepressants, antipsychotics, miscellaneous agents, 5-HT synthesis inhibitors, selective 5-HT reuptake inhibitors, and specific 5-HT receptor antagonists or agonists have shown a critical role in IBS management. A integrative approach for IBS management is a necessary. 展开更多
关键词 Psychological stress Irritable bowel syndrome Microbiota-gut-brain axis Immune activation
下载PDF
罗沙司他治疗血液透析患者红细胞生成素低反应性贫血的疗效观察 被引量:18
8
作者 董建华 范文静 +4 位作者 吴边 黄力 李川 樊蓉 葛永纯 《肾脏病与透析肾移植杂志》 CAS CSCD 北大核心 2021年第3期211-216,共6页
目的:探讨罗沙司他在维持性血液透析(MHD)患者红细胞生成素(EPO)低反应性贫血的治疗效果。方法:回顾性分析2020年5月至2021年2月的MHD患者22例,均患EPO低反应性贫血,即经EPO持续治疗3个月且最大剂量≥300 IU/(kg·周),但血红蛋白水... 目的:探讨罗沙司他在维持性血液透析(MHD)患者红细胞生成素(EPO)低反应性贫血的治疗效果。方法:回顾性分析2020年5月至2021年2月的MHD患者22例,均患EPO低反应性贫血,即经EPO持续治疗3个月且最大剂量≥300 IU/(kg·周),但血红蛋白水平仍不能升高至100g/L以上。转换为罗沙司他治疗后,监测血红蛋白和铁代谢变化,观察罗沙司他对EPO低反应性贫血的临床疗效。结果:22例患者中男性12例、女性10例,年龄55±16岁,中位透析龄102(38,163)月,干体重62.7±12.4 kg,基线血红蛋白81.1±10.3 g/L,4例(18.2%)转铁蛋白饱和度≤20%,8例(36.4%)血清铁蛋白≤200μg/L,EPO抗体均为阴性,EPO平均剂量12 272±2 979 IU/周。罗沙司他剂量106.4±9.5 mg/次,治疗1月、2月和3月后血红蛋白分别升至102.0±16.9 g/L、102.7±16.8 g/L和105.9±16.1 g/L(与基线相比,P均<0.001)。17例(77.2%)患者血红蛋白≥110 g/L,5例(22.7%)患者肾性贫血未改善,患者基础疾病分别为系统性红斑狼疮(3例)、抗中性粒细胞胞质抗体相关血管炎(1例),移植肾失功患者细小病毒感染(1例)。总铁结合力较基线升高(47.8±14.5μmol/L vs 39.7±9.9μmol/L,P=0.004),血清铁、转铁蛋白饱和度和血清铁蛋白无明显变化;C反应蛋白较基线下降[3.6(1.5, 5.6) mg/L vs 5.9(2.4, 9.3) mg/L,P=0.041],血钾较基线升高(5.21±0.77 mmol/L vs 4.72±1.00 mmol/L,P=0.033)。结论:罗沙司他可有效改善MHD患者EPO低反应性贫血,但部分自身免疫性疾病患者效果欠佳,其原因和机制尚待深入探讨。 展开更多
关键词 罗沙司他 肾性贫血 红细胞生成素低反应性 血液透析
下载PDF
突水水源的独立性权–模糊可变理论识别模型 被引量:16
9
作者 董东林 李祥 +3 位作者 林刚 卞建玲 曹成龙 吴恒 《煤田地质与勘探》 CAS CSCD 北大核心 2019年第5期48-53,共6页
在煤矿开采过程中,矿井水害事故频繁发生。为快速准确地找出矿井突水水源,降低矿井突水给煤矿生产带来的危害,以赵各庄矿为例,运用独立性权系数与模糊可变理论相结合的方法,选取了Na^+,Ca^2+,Mg^2+,Cl^–,SO4^2–和HCO3^– 6种水化学指... 在煤矿开采过程中,矿井水害事故频繁发生。为快速准确地找出矿井突水水源,降低矿井突水给煤矿生产带来的危害,以赵各庄矿为例,运用独立性权系数与模糊可变理论相结合的方法,选取了Na^+,Ca^2+,Mg^2+,Cl^–,SO4^2–和HCO3^– 6种水化学指标,对赵各庄矿的20组水样数据进行分析计算。结果表明:独立性权系数–模糊可变理论模型排除了水样中各指标间冗余信息的影响,克服了水样各变量间权重难以确定以及变量对水质影响不均匀的问题,可在一定程度上保证突水水源识别模型的准确度;Cl^–权重值远大于其他各项化学指标的权重值,即Cl^–对突水水源的识别结果影响较大;采用本文所建模型判别赵各庄矿的8组测试水样,判别准确率达87.5%,表明该模型在矿井突水水源识别中具有重要参考价值。 展开更多
关键词 突水水源识别 独立性权系数法 模糊可变集理论 水化学指标 赵各庄矿
下载PDF
A Comparative miRNAome Analysis Reveals Seven Fiber Initiation-Related and 36 Novel miRNAs in Developing Cotton Ovules 被引量:16
10
作者 Zheng-Ming Wang Wei Xue +5 位作者 Chun-Juan dong Long-Guo Jin Shao-Min bian Chuan Wang Xiu-Yun Wu Jin-Yuan Liu 《Molecular Plant》 SCIE CAS CSCD 2012年第4期889-900,共12页
An increasing number of microRNAs (miRNAs) have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to chara... An increasing number of microRNAs (miRNAs) have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to characterize miRNAomes from the ovules of wild-type upland cotton and a fiberless mutant during fiber initiation. Comparative miR- NAome analysis combined with northern blotting and RACE-PCR revealed seven fiber initiation-related miRNAs expressed in cotton ovules and experimentally validated targets of these miRNAs are involved in different cellular responses and metabolic processes, including transcriptional regulation, auxin and gibberellin signal transduction, actin bundles, and lignin biosynthesis. This paper describes a complex regulatory network consisting of these miRNAs expressed in cotton ovules to coordinate fiber initiation responses. In addition, 36 novel miRNAs and two conserved miRNAs were newly iden- tified, nearly doubling the number of known cotton miRNA families to a total of 78. Furthermore, a chromatin remodeling complex subunit and a pre-mRNA splicing factor are shown for the first time to be miRNA targets. To our knowledge, this study is the first systematic investigation of fiber initiation-related miRNAs and their targets in the developing cotton ovule, deepening our understanding of the important regulatory functions of miRNAs in cotton fiber initiation. 展开更多
关键词 Cotton ovules fiber initiation high-throughput sequencing molecular characterization newly identifiedmiRNAs.
原文传递
黄河上游水库群多目标优化调度研究 被引量:15
11
作者 贾一飞 董增川 +2 位作者 卞佳琪 钟敦宇 林梦然 《人民黄河》 CAS 北大核心 2019年第1期41-45,50,共6页
为了使黄河上游梯级水库群在丰、平、枯水年的实际调度中最大限度地发挥效益,建立黄河上游水库群的多目标优化调度模型,选择1989—2008年共20 a的实测径流长系列资料,利用改进的快速非劣排序遗传算法(NSGA-Ⅱ)对模型进行求解。从水库发... 为了使黄河上游梯级水库群在丰、平、枯水年的实际调度中最大限度地发挥效益,建立黄河上游水库群的多目标优化调度模型,选择1989—2008年共20 a的实测径流长系列资料,利用改进的快速非劣排序遗传算法(NSGA-Ⅱ)对模型进行求解。从水库发电、运行情况、供水满足度、防凌、生态等方面对模型计算结果进行分析,结果表明:在充分满足防凌和生态前提下,模型优化后的整个梯级水库群总发电量比"实际"发电量提高了2.07%、总缺水率平方和比实际降低了5.98%。 展开更多
关键词 水库调度 多目标 改进NSGA-Ⅱ算法 黄河上游
下载PDF
中国空间站再生生保系统的设计与实现 被引量:13
12
作者 刘向阳 高峰 +6 位作者 邓一兵 吴志强 李英斌 董文平 卞强 杨润泽 张滔 《中国科学:技术科学》 EI CSCD 北大核心 2022年第9期1375-1392,共18页
中国空间站中配置了再生生保系统,用于在长期载人航天飞行中实现环境控制和生命保障功能,在空间站内开展大气净化、氧气再生、冷凝水和尿液的净化回收.作为中国空间站的关键技术,以物理、化学方法为基础的再生生保系统包含电解制氧、CO_... 中国空间站中配置了再生生保系统,用于在长期载人航天飞行中实现环境控制和生命保障功能,在空间站内开展大气净化、氧气再生、冷凝水和尿液的净化回收.作为中国空间站的关键技术,以物理、化学方法为基础的再生生保系统包含电解制氧、CO_(2)去除、微量有害气体去除、尿处理、水处理和CO_(2)还原等多个系统.在神舟十二号飞行任务中,再生生保各系统运行稳定,全程保障了3人90天的任务要求,舱内物质循环与能量流动、物质消耗与循环节律得到在轨验证.本文阐述了再生生保系统的特点、研制过程、设计方案、地面和在轨验证情况. 展开更多
关键词 中国空间站 环境控制和生命保障 再生生保系统 在轨验证
原文传递
A Randomized, Controlled, Double-Blinded and Double- Dummy Trial of the Effect of Tongjiang Granule (通降颗粒) on the Nonerosive Reflux Disease of and Gan (肝)-Wei (胃) Incoordination Syndrome 被引量:14
13
作者 LI Bao-shuang LI Zhen-hua +6 位作者 TANG Xu-dong ZHANG Li-ying ZHAO Zing-pan bian Li-qun ZHANG Yin-qiang WANG Ping WANG Feng-yun 《Chinese Journal of Integrative Medicine》 SCIE CAS 2011年第5期339-345,共7页
Objective: To assess the effectiveness of Tongjiang Granule (TJG, 通降颗粒) on the patients with nonerosive reflux disease (NERD) of Gan (肝)-Wei (胃) incoordination syndrome, its impact on their quality of l... Objective: To assess the effectiveness of Tongjiang Granule (TJG, 通降颗粒) on the patients with nonerosive reflux disease (NERD) of Gan (肝)-Wei (胃) incoordination syndrome, its impact on their quality of life, and its safety. Method: A randomized, controlled, double-blinded, and double-dummy method was adopted in the trial. There were 120 NERD patients enrolled in the study and randomly divided into the experiment and control groups, each with 60 patients; drugs were distributed according to the drug number by patients' inclusion sequences. In the experiment group, patients were given TJG 10 g and mosapdde citrate dummy 5 mg three times a day, and in the control group, patients were given mosapdde citrate 5 mg and TJG dummy 10 g three times a day. The treatment courses of both groups were 4 weeks. Results: Among 120 included patients, 112 were screened for full analysis set (FAS), and 105 were screened per-protocol set (PPS). The results were as follows: (1) the improvement of total scores of symptom in the experiment group (0-4 week) were 15.93 ± 7.88 scores by FAS and 16.22 ±7.75 scores by PPS, and they were 10.43± 10.16 scores and 10.79± 10.27 scores in the control group, respectively. The 95% CI of net scores improvement between the two groups were 2.10- 8.90 scores and 1.92-8.94 scores in FAS and PPS; it was significantly better in the experiment group than that in the control group (P〈0.05). (2) The improvement of scores of major symptom in the experiment group (0-4 week) were 10.68±5.35 by FAS and 10.89±5.29 by PPS and 7.40±7.41 and 7.60±7.46 in the control group, respectively. The 95% CI of net scores improvement in the two groups were 0.85-5.71 and 0.71-5.69 in FAS and PPS separately, and the improvement in the experiment group was significantly better than that in the control group (P〈0.05). (3) The total effective rates were 86.0% and 61.8% in the experiment and the control group separately, and the Ridit analysis result 展开更多
关键词 Tongjiang Granule gastroesophageal reflux Gan-Wei incoordination syndrome
原文传递
2012-2021年江苏省扬州市流感流行病学及病原学特征 被引量:10
14
作者 姚静 王寅 +7 位作者 董玉颖 李晓君 张秀玲 黄瑶 卞宇旬 许蓉蓉 任薇 袁粉定 《实用临床医药杂志》 CAS 2023年第1期44-48,共5页
目的分析扬州市流感流行病学及病原学特征。方法应用描述流行病学方法对扬州市2012-2021年流感监测资料及病原检测结果进行分析。结果2012-2021年,扬州市共报告流感样病例(ILI)438072例,占门急诊病例比率(ILI%)为6.69%;0~4岁组和5~14岁... 目的分析扬州市流感流行病学及病原学特征。方法应用描述流行病学方法对扬州市2012-2021年流感监测资料及病原检测结果进行分析。结果2012-2021年,扬州市共报告流感样病例(ILI)438072例,占门急诊病例比率(ILI%)为6.69%;0~4岁组和5~14岁组在ILI中所占构成比最大。采用ILI%×流感核酸检测阳性率作为流感活动强度指标,结果显示流感流行时间主要集中在12月至次年3月,2012-2013、2020-2021年呈低流行状态,2014-2019年(尤其是2019年)出现流行高峰;流感核酸检测阳性率为9.61%。病原型别以季节性H3N2型为最多,其后依次为乙型Victoria流感、新甲型H1N1流感、乙型Yamagata流感。上述结果与流感暴发疫情一致。结论扬州市流感多发生于冬春季,各病原型别交替流行,每个流行周期(2~4年)有2~3种型别为优势株。疾制部门应重点关注婴幼儿、儿童群体,加强学校疫情防控指导力度,继续强化流感疫苗预防接种工作。 展开更多
关键词 流感 哨点监测 流行病学特征 病原学特征 流感样病例 流感活动强度
下载PDF
Measuring and evaluating SDG indicators with Big Earth Data 被引量:12
15
作者 Huadong Guo dong Liang +13 位作者 Zhongchang Sun Fang Chen Xinyuan Wang Junsheng Li Li Zhu Jinhu bian Yanqiang Wei Lei Huang Yu Chen Dailiang Peng Xiaosong Li Shanlong Lu Jie Liu Zeeshan Shirazi 《Science Bulletin》 SCIE EI CAS CSCD 2022年第17期1792-1801,共10页
The United Nations 2030 Agenda for Sustainable Development provides an important framework for economic,social,and environmental action.A comprehensive indicator system to aid in the systematic implementation and moni... The United Nations 2030 Agenda for Sustainable Development provides an important framework for economic,social,and environmental action.A comprehensive indicator system to aid in the systematic implementation and monitoring of progress toward the Sustainable Development Goals(SDGs)is unfortunately limited in many countries due to lack of data.The availability of a growing amount of multi-source data and rapid advancements in big data methods and infrastructure provide unique opportunities to mitigate these data shortages and develop innovative methodologies for comparatively monitoring SDGs.Big Earth Data,a special class of big data with spatial attributes,holds tremendous potential to facilitate science,technology,and innovation toward implementing SDGs around the world.Several programs and initiatives in China have invested in Big Earth Data infrastructure and capabilities,and have successfully carried out case studies to demonstrate their utility in sustainability science.This paper presents implementations of Big Earth Data in evaluating SDG indicators,including the development of new algorithms,indicator expansion(for SDG 11.4.1)and indicator extension(for SDG 11.3.1),introduction of a biodiversity risk index as a more effective analysis method for SDG 15.5.1,and several new high-quality data products,such as global net ecosystem productivity,high-resolution global mountain green cover index,and endangered species richness.These innovations are used to present a comprehensive analysis of SDGs 2,6,11,13,14,and 15 from 2010 to 2020 in China utilizing Big Earth Data,concluding that all six SDGs are on schedule to be achieved by 2030. 展开更多
关键词 Big Earth Data Big data Sustainable Development Goals(SDGs) Decision support CASEarth Digital Earth
原文传递
Small molecules for mesenchymal stem cell fate determination 被引量:13
16
作者 Yu-Hao Cheng Jing-Cheng dong Qin bian 《World Journal of Stem Cells》 SCIE 2019年第12期1084-1103,共20页
Mesenchymal stem cells(MSCs)are adult stem cells harboring self-renewal and multilineage differentiation potential that are capable of differentiating into osteoblasts,adipocytes,or chondrocytes in vitro,and regulatin... Mesenchymal stem cells(MSCs)are adult stem cells harboring self-renewal and multilineage differentiation potential that are capable of differentiating into osteoblasts,adipocytes,or chondrocytes in vitro,and regulating the bone marrow microenvironment and adipose tissue remodeling in vivo.The process of fate determination is initiated by signaling molecules that drive MSCs into a specific lineage.Impairment of MSC fate determination leads to different bone and adipose tissue-related diseases,including aging,osteoporosis,and insulin resistance.Much progress has been made in recent years in discovering small molecules and their underlying mechanisms control the cell fate of MSCs both in vitro and in vivo.In this review,we summarize recent findings in applying small molecules to the trilineage commitment of MSCs,for instance,genistein,medicarpin,and icariin for the osteogenic cell fate commitment;isorhamnetin,risedronate,and arctigenin for pro-adipogenesis;and atractylenolides and dihydroartemisinin for chondrogenic fate determination.We highlight the underlying mechanisms,including direct regulation,epigenetic modification,and post-translational modification of signaling molecules in the AMPK,MAPK,Notch,PI3K/AKT,Hedgehog signaling pathways etc.and discuss the small molecules that are currently being studied in clinical trials.The target-based manipulation of lineage-specific commitment by small molecules offers substantial insights into bone marrow microenvironment regulation,adipose tissue homeostasis,and therapeutic strategies for MSC-related diseases. 展开更多
关键词 MESENCHYMAL stem CELL MESENCHYMAL STROMAL CELL CELL FATE determination Small molecules Natural compounds Signaling PATHWAYS
下载PDF
30例新型冠状病毒肺炎核酸持续阳性患者临床特征回顾性分析 被引量:13
17
作者 丛晓东 杨金亮 +13 位作者 李斌 石嘉恒 董国菊 王冰 线永悦 朱浩宁 杨志旭 阮连国 吕诚 边永君 齐文升 李浩 苗青 黄璐琦 《中医杂志》 CSCD 北大核心 2020年第24期2121-2125,共5页
目的分析探讨新型冠状病毒肺炎(简称“新冠肺炎”)新型冠状病毒核酸持续阳性超过4周患者的临床特征。方法采用回顾性分析方法,纳入武汉市金银潭医院南一病区2020年1月28日至3月30日收治的新型冠状病毒核酸检测阳性持续时间>4周的新... 目的分析探讨新型冠状病毒肺炎(简称“新冠肺炎”)新型冠状病毒核酸持续阳性超过4周患者的临床特征。方法采用回顾性分析方法,纳入武汉市金银潭医院南一病区2020年1月28日至3月30日收治的新型冠状病毒核酸检测阳性持续时间>4周的新冠肺炎患者共30例,采集其一般资料、临床资料并分析患者临床特征及体质类型分布规律。结果30例新冠肺炎患者中包括持续阳性未能出院患者10例,出院或隔离后复查阳性者20例。年龄34~86岁,平均(60.40±14.46)岁,≥60岁者19例(63.3%);临床分型:普通型8例(26.7%),重型22例(73.3%);主要基础疾病:高血压病14例次(46.6%),糖尿病6例次(20.0%),冠心病5例次(16.7%);初始发病时主症:发热(20例,占66.7%),喘息(10例,占33.3%),咳嗽(7例,占23.3%);咽拭子核酸反复阳性24例次(80.0%),痰液核酸反复阳性16例次(53.3%);接受过抗生素治疗24例次(80.0%),接受过抗病毒药物治疗16例次(53.4%),接受过中药治疗25例次(83.3%);舌质暗淡者19例(63.3%),舌质红11例(36.7%);舌苔腻者21例(70.0%),舌苔少者5例(16.7%),苔薄白者4例(13.3%);痰湿体质12例(40.0%),气郁体质8例(26.7%),气虚体质5例(16.6%),湿热体质3例(10.0%),阴虚体质2例(6.7%)。结论新型冠状病毒核酸持续阳性的患者中高龄、基础疾病多者相对较多,高血压病为最常见的合并基础病,咽拭子反复阳性最为常见;舌质暗淡及舌苔腻者以及痰湿、气郁体质的患者较多,故益气扶正、化湿驱邪、调畅气机或是其治疗的方向。 展开更多
关键词 新型冠状病毒肺炎 新型冠状病毒核酸 核酸持续阳性 临床特征 中医体质
原文传递
面向多模态磁共振脑瘤图像的小样本分割方法 被引量:12
18
作者 董阳 潘海为 +3 位作者 崔倩娜 边晓菲 滕腾 王邦菊 《计算机应用》 CSCD 北大核心 2021年第4期1049-1054,共6页
针对脑肿瘤磁共振成像(MRI)模态多、训练数据少、类别不平衡以及各个私有数据库差异大等导致分割困难的问题,引入小样本分割方法,并提出基于U-net的原型网络(PU-net)模型用以对脑肿瘤磁共振(MR)图像进行分割。首先对U-net的结构进行调... 针对脑肿瘤磁共振成像(MRI)模态多、训练数据少、类别不平衡以及各个私有数据库差异大等导致分割困难的问题,引入小样本分割方法,并提出基于U-net的原型网络(PU-net)模型用以对脑肿瘤磁共振(MR)图像进行分割。首先对U-net的结构进行调整来提取各类瘤体的特征用以计算原型;然后在原型网络的基础上,逐像素利用原型对各空间位置进行分类,从而获取各类瘤体区域的概率图与分割结果;针对瘤体像素类别不平衡问题,采用自适应权重交叉熵损失函数来减小背景类对损失计算的影响;最后加入原型校验机制,即融合利用分割得到的概率图和查询图像对原型进行校验。所提方法在公开数据集BraTS2018上进行实验,得到的平均Dice系数为0.654,阳性预测率为0.662,灵敏度为0.687,豪斯多夫距离为3.858,平均交并比(mIOU)达到61.4%,与最新的小样本分割方法原型校准网络(PANet)和基于注意力的多上下文引导网络(A-MCG)相比各项指标均有所提升。结果显示引入小样本分割方法对脑肿瘤MR图像进行分割有不错的效果,采用自适应权重交叉熵损失函数也有着一定的帮助,可以对脑肿瘤诊断治疗起到有效的辅助作用。 展开更多
关键词 脑肿瘤 多模态图像 医学图像分割 小样本分割 深度学习
下载PDF
云南割手密创新种质F_2的主成分聚类分析及其评价 被引量:11
19
作者 俞华先 田春艳 +8 位作者 经艳芬 安汝东 郎荣斌 边芯 董立华 周清明 杨李和 孙有芳 桃联安 《植物遗传资源学报》 CAS CSCD 北大核心 2019年第3期624-633,共10页
云南割手密是甘蔗育种中比较宝贵的野生种质资源。对68份云南割手密F2创新种质材料的9个主要工农艺性状进行主成分分析,并以前3个主成分为基础,分别作聚类分析和二维排序图。结果表明:68份云南割手密F2创新种质的变异系数为10.57%~35.3... 云南割手密是甘蔗育种中比较宝贵的野生种质资源。对68份云南割手密F2创新种质材料的9个主要工农艺性状进行主成分分析,并以前3个主成分为基础,分别作聚类分析和二维排序图。结果表明:68份云南割手密F2创新种质的变异系数为10.57%~35.30%,11月份理论含糖量和单产的变异系数超过30%,说明11月份理论含糖量和单产性状的变异潜力较高。主成分分析结果表明,单茎重产量因子、锤度糖分因子和丛有效茎含糖量这3个主因子提供了原始性状80.8292%的信息;在欧氏距离为10.00处将68份材料分为4类,各个类群具有不同的特点,在甘蔗杂交育种上可以根据不同类群的特点加以利用;二维排序表明云割F211-50、云割F211-56、云割F211-40、云割F211-66、云割F211-77、云割F211-10、云割F211-19、云割F211-85、云割F211-45、云割F211-37、云割F211-25、云割F211-23、云割F211-18等13份材料的3个主成分构成因子协调性最好,可在育种中加以利用。 展开更多
关键词 割手密 创新种质 相关分析 主成分分析 聚类分析
下载PDF
A natural variation in Ribonuclease H-like gene underlies Rht8 to confer“Green Revolution”trait in wheat 被引量:10
20
作者 Lingling Chai Mingming Xin +17 位作者 Chaoqun dong Zhaoyan Chen Huijie Zhai Junhong Zhuang Xuejiao Cheng Naijiao Wang Jia Geng Xiaobo Wang Ruolin bian Yingyin Yao Weilong Guo Zhaorong Hu Huiru Peng Guihua Bai Qixin Sun Zhenqi Su Jie Liu Zhongfu Ni 《Molecular Plant》 SCIE CAS CSCD 2022年第3期377-380,共4页
Dear Editor,Introduction of gibberellin(GA)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain ... Dear Editor,Introduction of gibberellin(GA)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain yields worldwide since the 1960s(Peng et al.,1999;Velde et al.,2021).However,Rht-B1b/D1b also reduce coleoptiles,which is undesired in dryland regions where deep planting is essential for seedling establishment(Rebetzke et al.,1999,Rebetzke et al.,2001;Ellis et al.,2004). 展开更多
关键词 AESTIVUM SEEDLING CULTIVAR
原文传递
上一页 1 2 29 下一页 到第
使用帮助 返回顶部