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Prevalence of Autism Spectrum Disorder in China:A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years 被引量:210
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作者 Hao Zhou Xiu Xu +25 位作者 Weili Yan Xiaobing Zou Lijie Wu Xuerong Luo Tingyu Li Yi Huang Hongyan Guan Xiang Chen Meng Mao kun Xia Lan Zhang Erzhen Li Xiaoling Ge Lili Zhang Chunpei Li Xudong Zhang Yuanfeng Zhou Ding Ding Andy Shih Eric Fombonne Yi zheng Jisheng Han Zhongsheng Sun Yong-hui Jiang Yi Wang LATENT-NHC Study Team 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第9期961-971,共11页
This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multis... This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling.The Modified Chinese Autism Spectrum Rating Scale was used for the screening process.Of the target population of 142,086 children,88.5%(n=125,806) participated in the study.A total of 363 children were confirmed as having ASD.The observed ASD prevalence rate was 0.29%(95% CI:0.26%-0.32%) for the overall population.After adjustment for response rates,the estimated number of ASD cases was867 in the target population sample,thereby achieving an estimated prevalence of 0.70%(95% CI:0.64%-0.74%).The prevalence was significantly higher in boys than in girls(0.95%;95% CI:0.87%-1.02% versus 0.30%;95%CI:0.26%-0.34%;P <0.001).Of the 363 confirmed ASD cases,43.3% were newly diagnosed,and most of those(90.4%) were attending regular schools,and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity.Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children. 展开更多
关键词 Autism spectrum disorder PREVALENCE COMORBIDITY Autism Spectrum Rating Scale China
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规模化在线学习准备好了吗?--后疫情时期的在线学习与智能技术应用思考 被引量:93
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作者 万昆 郑旭东 任友群 《远程教育杂志》 CSSCI 北大核心 2020年第3期105-112,共8页
在疫情防控的关键时期,规模化在线学习是落实“停课不停学”的重要方式。与以往的在线学习相比,规模化在线学习在学习场所、学习任务、学习同伴、思维方式、评价方式等多个方面发生了转变。它是教育信息化实践的一次特殊尝试,同时,其也... 在疫情防控的关键时期,规模化在线学习是落实“停课不停学”的重要方式。与以往的在线学习相比,规模化在线学习在学习场所、学习任务、学习同伴、思维方式、评价方式等多个方面发生了转变。它是教育信息化实践的一次特殊尝试,同时,其也在重塑在线学习的价值,形成了一种全新的学习生态。为了了解我国规模化在线学习的现状、准备度等情况,运用问卷调查法,对全国3148名学生进行调查研究,调查结果显示:一是在线学习满意度较低,感知教师支持较高,在线学习准备度一般。其中,在线交互效能感最高,计算机自我效能感准备不足;二是人口学因素对规模化在线学习准备度有不同程度的影响,年级、所在区域、每天在线学习时长所带来的差异影响显著;三是在线学习态度、教师支持、计算机自我效能感、自我导向学习、学习动机、学习控制力、在线交互效能感等,正向影响学生的在线学习满意度。因此,要提高规模化在线学习效果,可以从提升师生信息素养、加强培养自主学习能力、改善家校互动模式、增强教师支持、关注农村和留守儿童的在线学习等方面着手。在后疫情时期,还应进一步思考“教师如何迎接在线学习”“学生如何学习”“如何设计在线课程和实现优质教育资源共享”“在线学习如何与线下学习有机融合”等问题。 展开更多
关键词 规模化在线学习 在线学习准备度 人工智能 策略研究 后疫情时期
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Impacts of chemical fertilizer reduction and organic amendments supplementation on soil nutrient,enzyme activity and heavy metal content 被引量:75
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作者 NING Chuan-chuan GAO Peng-dong +3 位作者 WANG Bing-qing LIN Wei-peng JIANG Ni-hao CAI kun-zheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1819-1831,共13页
Excessive use of agro-chemicals (such as mineral fertilizers) poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmenta... Excessive use of agro-chemicals (such as mineral fertilizers) poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to de- velop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009-2012. The experiment included four treatments: 100% chemical fertilizer (CF100), 80% chemical fertilizer (CF80), 60% chemical fertilizer and 20% organic fertilizer (CF60+OM20), and 40% chemical fertilizer and 40% organic fertilizer (CF40+OM40). Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction (CF80) had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer (CF60+OM20, CF40+OM40) significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continu- ous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety. 展开更多
关键词 chemical fertilizer organic amendments soil fertility VEGETABLE soil health heavy metal
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近30年来京津冀地区湿地景观变化及其驱动因素 被引量:58
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作者 吕金霞 蒋卫国 +4 位作者 王文杰 陈坤 邓越 陈征 荔琢 《生态学报》 CAS CSCD 北大核心 2018年第12期4492-4503,共12页
湿地是水陆生态系统的转换区,是地球上生物多样性和生产力最高的生态系统之一。在快速城镇化和社会经济发展的推动下,京津冀地区湿地生态环境面临较大地威胁。利用1980年代末到2015年7期土地生态遥感解译数据,运用GIS空间分析和主成分... 湿地是水陆生态系统的转换区,是地球上生物多样性和生产力最高的生态系统之一。在快速城镇化和社会经济发展的推动下,京津冀地区湿地生态环境面临较大地威胁。利用1980年代末到2015年7期土地生态遥感解译数据,运用GIS空间分析和主成分分析方法,分析了京津冀地区湿地景观时空变化及其驱动力。研究结果表明:(1)1980s末—2015年期间,京津冀地区湿地面积的变化呈现从略微增长到快速减少趋势,近十年减少趋势略有减缓。湿地总面积减少了2695.05 km2,较1980s末年减少了20.08%;河北省湿地面积减少最多,且天然湿地减少占据主导地位,其次是天津市和北京市。(2)湿地面积损失较为严重的区域主要分布在环渤海区域、北京市和河北省张家口市和唐山市。湿地受损主要是水田和滩涂向非湿地转换引起的。(3)水田和水库坑塘构成的人工湿地是京津冀地区优势景观类型。湖泊、河渠、滩地破碎度增加,且空间分布离散,连通性差。(4)选取9个驱动因素指标进行主成分分析,人类活动是影响湿地景观格局变化的主要因素,城市扩张和农业发展是侵占湿地的主要表现形式,此外气候和政策等因素也对湿地变化存在一定影响。 展开更多
关键词 京津冀地区 湿地 景观格局指数 驱动因素
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Outcomes of primary percutaneous coronary intervention for acute ST-elevation myocardial infarction in patients aged over 75 years 被引量:54
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作者 ZHANG Qi ZHANG Rui-yan ZHANG Jian-sheng HU Jian YANG Zhen-kun zheng Ai-fang ZHANG Xian SHEN Wei-feng 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第14期1151-1156,共6页
Background The optimal reperfusion strategy in elderly patients with ST-elevation myocardial infarction (STEMI) remains unclear. The purpose of this study was to evaluate the safety, in-hospital and one-year clinica... Background The optimal reperfusion strategy in elderly patients with ST-elevation myocardial infarction (STEMI) remains unclear. The purpose of this study was to evaluate the safety, in-hospital and one-year clinical outcomes for patients 〉75 years of age with STEMI receiving primary percutaneous coronary intervention (PCI), compared with those treated by conservative approach. Methods One hundred and two patients 〉75 years of age with STEMI presented 〈12 hours were randomly allocated to primary PCI (n=50) or conservative therapy only (n=52). The baseline characteristics, in-hospital outcome and major adverse cardiac events (MACE), including death, non-fatal myocardial infarction and target vessel revascularization at one-year clinical follow-up were compared between the two groups. Results Age, gender distribution, risk factors for coronary artery disease, infarct site and clinical functional status were similar between the two groups, but the patients in primary PCI group received less low-molecular- weight heparin during hospitalization. Compared with conservative group, the patients in primary PCI group had significantly lower occurrence rate of re-infarction and death and shortened hospital stay. The composite endpoint for in-hospital survivals at 30-day follow-up was similar between the two groups, but one-year MACE rate was significantly lower in the primary PCI group (21.3% and 45.2%, P=0.029). Left ventricular ejection fraction was not significantly changed in both groups during follow-up. Multivariate analysis revealed that primary PCI (OR=0.34, 95% CI: 0.21-0.69, P =0.03) improved MACE-free survival rate for STEMI patients aged 〉 75 years. Conclusion Our results indicated that primary PCI was safe and effective in reducing in-hospital mortality and one-year MACE rate for elderly patients with STEMI. 展开更多
关键词 myocardial infarction ELDERLY ANGIOPLASTY OUTCOME
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安徽发现草地贪夜蛾为害早播小麦 被引量:49
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作者 徐丽娜 胡本进 +8 位作者 苏卫华 戚仁德 邱坤 郑兆阳 张启勇 周子燕 戚士胜 胡飞 王振营 《植物保护》 CAS CSCD 北大核心 2019年第6期87-89,共3页
2019年5月17日,在安徽省黄山市黄山区发现草地贪夜蛾为害春玉米,首次证实草地贪夜蛾入侵安徽,截至8月25日全省16市全部见虫。2019年10月22日,淮南市寿县窑口镇早播小麦田发现疑似该虫为害,经鉴定,确认为草地贪夜蛾。调查发现,全田均可... 2019年5月17日,在安徽省黄山市黄山区发现草地贪夜蛾为害春玉米,首次证实草地贪夜蛾入侵安徽,截至8月25日全省16市全部见虫。2019年10月22日,淮南市寿县窑口镇早播小麦田发现疑似该虫为害,经鉴定,确认为草地贪夜蛾。调查发现,全田均可见该虫为害状,百株被害率最高达84.21%,每平方米最高虫量43头。调查提示,入侵安徽的草地贪夜蛾种群可取食为害小麦,应加强其在麦田发生情况的监测。 展开更多
关键词 草地贪夜蛾 小麦 为害特征 被害率
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:40
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su zheng-Qiu Yao Ya-Nan Wang Xiao-zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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金属材料增材制造及其在民用航空领域的应用研究现状 被引量:37
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作者 常坤 梁恩泉 +4 位作者 张韧 郑敏 魏雷 黄文静 林鑫 《材料导报》 EI CAS CSCD 北大核心 2021年第3期3176-3182,共7页
金属增材制造技术以逐层快速熔/凝、堆积金属或合金材料为基本原理,以"添加"制造的方式成形任意形状零件,具有成形效率高、材料利用率高、成本低、复杂异形结构和高熔点材料的成形能力强等优点,在民用航空构件的减重、快速构... 金属增材制造技术以逐层快速熔/凝、堆积金属或合金材料为基本原理,以"添加"制造的方式成形任意形状零件,具有成形效率高、材料利用率高、成本低、复杂异形结构和高熔点材料的成形能力强等优点,在民用航空构件的减重、快速构型更改、集成化制造等方面具有传统工艺无法比拟的技术优势。面向增材制造技术的金属原材料和成形工艺丰富多样,为制备不同尺寸、不同形状、不同使用环境要求的构件提供了更多的选择,为减重、增效、成本控制提供了新的路径。因此,国内外均在积极制订相关重大战略规划以抢占增材制造创新技术先机、推进制造业的转型升级。全球制造商和高校等机构开展了大量增材制造原材料、工艺、性能方面的应用研究,其中以民用航空尖端制造业的应用研究最为典型。与其他领域不同,增材制造金属构件在民机上的装机应用需要经历严格的适航验证程序,形成标准规范技术体系,实现制造过程和产品质量的稳定可控,最终才能装机使用。本文介绍了金属增材制造的国内外政策概况、原材料与成形工艺分类、无损检测类型、民用飞机的应用研究情况,指出了针对金属增材制造在民用航空领域扩大应用的研究和发展趋势。 展开更多
关键词 民用航空 金属材料 增材制造
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入侵安徽省草地贪夜蛾的遗传分析 被引量:35
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作者 徐丽娜 胡本进 +8 位作者 苏贤岩 戚仁德 苏卫华 邱坤 周子燕 郑兆阳 张启勇 胡飞 王振营 《植物保护》 CAS CSCD 北大核心 2019年第5期47-53,共7页
2019年5月17日在安徽省黄山市黄山区发现草地贪夜蛾为害春玉米,首次证实草地贪夜蛾入侵安徽。本研究采集安徽省7市13县(区)草地贪夜蛾样本共167份,利用线粒体细胞色素C氧化酶亚基Ⅰ基因(cytochrome c oxidase subunitⅠ,COⅠ),以及位于... 2019年5月17日在安徽省黄山市黄山区发现草地贪夜蛾为害春玉米,首次证实草地贪夜蛾入侵安徽。本研究采集安徽省7市13县(区)草地贪夜蛾样本共167份,利用线粒体细胞色素C氧化酶亚基Ⅰ基因(cytochrome c oxidase subunitⅠ,COⅠ),以及位于Z染色体上的磷酸甘油醛异构酶基因(triose-phosphate isomerase,Tpi)两个分子标记对样品的群体遗传特征进行分析。基于线粒体COⅠ基因分析结果显示,安徽省草地贪夜蛾样本中86.23%是水稻型,13.77%是玉米型,而且安徽地区样品COⅠ序列特征与美国佛罗里达州种群高度一致。针对水稻型和玉米型的Tpi基因序列10个差异单倍型位点进行分析,发现安徽草地贪夜蛾样品Tpi基因的第3和4位差异单倍型位点有3种不同类型。其中118个样本为玉米型(AT),20个样本为水稻型(GA),29个样本为杂合型(AT/GA),但根据差异单倍型位点的数量判断,所有样品仍属于玉米型。草地贪夜蛾在原产地的多种寄主,如玉米、水稻、大豆、棉花等,在安徽省均有种植,该虫对安徽省粮食生产构成巨大安全隐患。 展开更多
关键词 草地贪夜蛾 分子鉴定 玉米型 水稻型
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MRI动态增强成像参数直方图分析对局部晚期宫颈癌放化疗后的预后评估价值 被引量:33
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作者 赵博 曹崑 +4 位作者 李晓婷 李小凡 郑虹 朱海涛 孙应实 《中华放射学杂志》 CAS CSCD 北大核心 2019年第3期218-223,共6页
目的探讨多期动态增强MRI扫描(DCE-MRI)直方图分析对局部晚期宫颈癌放化疗后预后的预测价值。方法回顾性分析北京大学肿瘤医院2008年7月至2014年3月,经活检病理确诊为宫颈癌,且临床分期为ⅠB~Ⅳ期无法手术而接受完整的根治性同步放化疗... 目的探讨多期动态增强MRI扫描(DCE-MRI)直方图分析对局部晚期宫颈癌放化疗后预后的预测价值。方法回顾性分析北京大学肿瘤医院2008年7月至2014年3月,经活检病理确诊为宫颈癌,且临床分期为ⅠB~Ⅳ期无法手术而接受完整的根治性同步放化疗的75例患者。患者在同步放化疗前行盆腔常规MRI及DCE-MRI扫描,获得4个血流动力学参数正性增强积分(PEI)、最大上升斜率(MSI)、最大下降斜率(MSD)和信号增强比率(SER)。在后处理软件中以T2WI图像为基准图勾画全肿瘤区域ROI然后匹配至DCE-MRI及参数图中,采用直方图软件计算各病灶的动态增强参数平均值、中位值、最大值、最小值、第10百分位、第90百分位值、峰度值及偏度值。随访时间2.1~94.6个月,中位随访时间54.7个月。采用Cox单因素分析对连续变量分析筛选放化疗远期效果预后相关危险因素(P<0.1),然后进行Pearson相关性检验对筛选出的参数进行相关性分析。排除有相关性的参数,其余参数进行Cox多因素回归分析检验变量是否为独立预后危险因素,采用Kaplan-Meier曲线评估生存情况。结果75例ⅠB~Ⅳ期同步放化疗子宫颈癌患者中,死亡16例、转移3例、1例病变持续进展。MSI的中位值、平均值、第90百分位值及第10百分位值,PEI的偏度值、最小值、峰度值是宫颈癌同步放化疗无疾病生存的影响因素(P<0.1)。采用MSI中位值及PEI最小值、偏度值、峰度值进行Cox多因素分析,宫颈癌PEI峰度值是宫颈癌无疾病生存的独立影响因素(风险比为1.658,P=0.001)。结论PEI峰度值是宫颈癌同步放化疗后无疾病生存独立的影响因素。 展开更多
关键词 宫颈肿瘤 远期疗效 磁共振成像 直方图分析
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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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膝关节单髁置换术治疗膝关节内侧间室骨关节炎的近期疗效评价 被引量:31
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作者 雷堃 张文 +3 位作者 高磊 郑伟 刘春新 李宽新 《中华骨与关节外科杂志》 2019年第3期201-205,共5页
背景:对于保守治疗无效的膝关节骨关节炎(KOA),传统多采用人工全膝关节置换术(TKA)。但对于单间室的KOA患者,TKA就不是最合适的术式。随着微创外科学的发展,人工膝关节单髁置换术(UKA)在临床上逐渐应用。目的:通过与TKA比较,评价UKA治... 背景:对于保守治疗无效的膝关节骨关节炎(KOA),传统多采用人工全膝关节置换术(TKA)。但对于单间室的KOA患者,TKA就不是最合适的术式。随着微创外科学的发展,人工膝关节单髁置换术(UKA)在临床上逐渐应用。目的:通过与TKA比较,评价UKA治疗膝关节内侧间室骨关节炎的近期临床疗效。方法:收集2015年10月至2017年10月间膝关节内侧间室骨关节炎患者50例。其中23例行UKA(UKA组),27例行TKA(TKA组)。记录并比较两组患者手术时间、术中出血量及术后患者膝关节屈曲90°所用时间,以及术前、术后1、6、12个月美国特种外科医院膝关节评分(HSS)、疼痛视觉模拟评分(VAS)、人工关节被遗忘指数评分(FJS)。结果:所有患者术后均随访12~32个月,平均随访(21.5±5.9)个月。UKA组患者手术时间、术后膝关节屈曲90°所用时间均较TKA组患者短[(98.0±7.1)min vs(107.8±6.6)min,(6.9±2.3)d vs(11.3±3.4)d],术中出血量也较TKA组患者少[(151.5±19.4)ml vs(308.4±39.3)ml],且差异均有统计学意义(t=5.037、5.495、18.743,P均<0.001)。两组患者术后12个月疼痛VAS评分均低于、HSS评分均高于术前[TKA组:(2.9±1.6)分vs(7.8±0.7)分,(86.9±3.7)分vs(54.3±2.8)分;UKA组:(2.9±0.9)分vs(7.9±1.4)分,(88.1±5.3)分vs(57.0±3.6)分],且差异均有统计学意义(t=21.634、-36.494、23.014、-23.233,P均<0.05);而术前、术后12个月UKA组与TKA组患者疼痛VAS评分、HSS评分差异均无统计学意义。两组患者术后12个月FJS评分均高于术后6个月[(58.9±3.4)分vs(44.9±2.5)分,(72.7±2.85)分vs(58.1±1.3)分,且差异均有统计学意义(t=-13.763、-17.103,P均<0.05);而术后6个月、术后12个月UKA组患者FJS评分均高于TKA组患者,且差异也均有统计学意义(t=-12.974、-15.749,P均<0.05)。结论:与TKA比较,UKA治疗膝关节内侧间室骨关节炎患者保留膝关节内的正常结构较多,手术时间短,创伤小,术后患者主观感受也更好,疗效满意,值得临� 展开更多
关键词 单髁置换术 膝关节骨关节炎 内侧间室 治疗结果
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山水林田湖草生态保护修复的系统思想——践行“绿水青山就是金山银山” 被引量:31
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作者 姜霞 王坤 +2 位作者 郑朔方 胡小贞 储昭升 《环境工程技术学报》 CAS 2019年第5期475-481,共7页
我国地域广阔,但由于人口基数庞大,可利用国土资源空间分布不均。在我国经济实力和人民生活水平得到显著提升的当今,如何在有限的国土资源下,实现经济的可持续发展,促进社会经济与环境保护的协同发展,成为迫切需要解决的发展难题。习近... 我国地域广阔,但由于人口基数庞大,可利用国土资源空间分布不均。在我国经济实力和人民生活水平得到显著提升的当今,如何在有限的国土资源下,实现经济的可持续发展,促进社会经济与环境保护的协同发展,成为迫切需要解决的发展难题。习近平总书记提出的“山水林田湖草是一个生命共同体”的重要理念和系统治理思路为解决这一发展难题指明了方向。解析了山水林田湖草生态保护修复的战略背景;阐释了山水林田湖草生态保护修复的指导思想、基本原则和系统设计思路;提出了山水林田湖草生态保护修复工作的重点任务,包括编制修复方案,科学确定空间布局,优化调整产业结构与人口布局,因地制宜地开展生态修复,多部门联动推进生态保护修复等,并明确了其技术要求。 展开更多
关键词 山水林田湖草 生命共同体 系统治理 生态功能 绿水青山
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Circulating tumor cells:biology and clinical significance 被引量:31
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作者 Danfeng Lin Lesang Shen +8 位作者 Meng Luo kun Zhang Jinfan Li Qi Yang Fangfang Zhu Dan Zhou Shu zheng Yiding Chen Jiaojiao Zhou 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第12期3510-3533,共24页
Circulating tumor cells(CTCs)are tumor cells that have sloughed off the primary tumor and extravasate into and circulate in the blood.Understanding of the metastatic cascade of CTCs has tremendous potential for the id... Circulating tumor cells(CTCs)are tumor cells that have sloughed off the primary tumor and extravasate into and circulate in the blood.Understanding of the metastatic cascade of CTCs has tremendous potential for the identification of targets against cancer metastasis.Detecting these very rare CTCs among the massive blood cells is challenging.However,emerging technologies for CTCs detection have profoundly contributed to deepening investigation into the biology of CTCs and have facilitated their clinical application.Current technologies for the detection of CTCs are summarized herein,together with their advantages and disadvantages.The detection of CTCs is usually dependent on molecular markers,with the epithelial cell adhesion molecule being the most widely used,although molecular markers vary between different types of cancer.Properties associated with epithelial-tomesenchymal transition and stemness have been identified in CTCs,indicating their increased metastatic capacity.Only a small proportion of CTCs can survive and eventually initiate metastases,suggesting that an interaction and modulation between CTCs and the hostile blood microenvironment is essential for CTC metastasis.Single-cell sequencing of CTCs has been extensively investigated,and has enabled researchers to reveal the genome and transcriptome of CTCs.Herein,we also review the clinical applications of CTCs,especially for monitoring response to cancer treatment and in evaluating prognosis.Hence,CTCs have and will continue to contribute to providing significant insights into metastatic processes and will open new avenues for useful clinical applications. 展开更多
关键词 CLINICAL eventually DEEPENING
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InterTAN髓内钉与股骨近端防旋髓内钉固定治疗高龄不稳定型股骨转子间骨折的疗效比较 被引量:30
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作者 张昆 刘家帮 +4 位作者 李冬 张清华 裴征 李沼 关振 《中华创伤骨科杂志》 CAS CSCD 北大核心 2019年第12期1052-1058,共7页
目的比较InterTAN髓内钉与股骨近端防旋髓内钉(PFNA)固定治疗高龄不稳定型股骨转子间骨折的临床疗效。方法回顾性分析2013年1月至2018年3月期间北京大学首钢医院骨科收治的164例高龄不稳定型股骨转子间骨折患者资料。根据内固定方式不... 目的比较InterTAN髓内钉与股骨近端防旋髓内钉(PFNA)固定治疗高龄不稳定型股骨转子间骨折的临床疗效。方法回顾性分析2013年1月至2018年3月期间北京大学首钢医院骨科收治的164例高龄不稳定型股骨转子间骨折患者资料。根据内固定方式不同分为两组:InterTAN髓内钉组93例,男30例,女63例;年龄为(84.5±2.4)岁;骨折AO分型:31-A2.2型53例,31-A2.3型28例,31-A3型12例。PFNA组71例,男19例,女52例;年龄为(83.8±2.3)岁;骨折AO分型:31-A2.2型41例,31-A2.3型22例,31-A3型8例。比较两组患者的下地负重时间、大腿疼痛发生率、髋关节功能、影像学相关并发症(髋内翻畸形、内固定物切出)发生率及术后生活质量等。结果两组患者术前一般资料比较差异均无统计学意义(P>0.05),具有可比性。InterTAN髓内钉组患者影像学相关并发症发生率[5.4%(5/93)]显著低于PFNA组患者[18.3%(13/71)],下地负重时间[(60.0±13.6)d]显著短于PFNA组患者[(65.8±11.0)d],大腿疼痛发生率[3.2%(3/93)]显著低于PFNA组患者[12.7%(9/71)],差异均有统计学意义(P<0.05)。153例患者术后获平均39个月(12~75个月)随访。末次随访时InterTAN髓内钉组患者髋关节Harris评分[(78.3±12.2)分]显著高于PFNA组患者[(73.6±11.3)分],健康调查简表中生理机能[(68.6±15.4)分]、一般健康状况[(78.2±10.3)分]、活力[(74.0±12.6)分]及精神健康[(80.6±9.9)分]4个维度评分显著高于PFNA组患者[(64.1±9.9)、(74.9±9.0)、(69.9±10.9)、(77.4±8.8)分],差异均有统计学意义(P<0.05)。结论两种内固定术式均能使骨折愈合,恢复高龄患者髋关节功能。但与PFNA比较,InterTAN髓内钉固定术后患者下地时间更早,髋内翻畸形发生率更低,日常生活质量恢复更好。 展开更多
关键词 髋骨折 骨折固定术 髓内 骨钉 生活质量
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甲维盐·氯虫苯甲酰胺组合物对草地贪夜蛾室内毒力测定及田间防治效果 被引量:28
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作者 胡飞 苏贤岩 +7 位作者 胡本进 周子燕 徐丽娜 邱坤 郑兆阳 张启勇 廖辰 王振营 《植物保护》 CAS CSCD 北大核心 2020年第3期303-307,共5页
为筛选出甲维盐与氯虫苯甲酰胺复配防治草地贪夜蛾的最佳配比,采用浸虫法测定了甲维盐、氯虫苯甲酰胺及组合物对草地贪夜蛾的室内毒力,并基于最佳增效配比进行了田间防治效果评价试验。结果表明,甲维盐和氯虫苯甲酰胺复配组合在二者质... 为筛选出甲维盐与氯虫苯甲酰胺复配防治草地贪夜蛾的最佳配比,采用浸虫法测定了甲维盐、氯虫苯甲酰胺及组合物对草地贪夜蛾的室内毒力,并基于最佳增效配比进行了田间防治效果评价试验。结果表明,甲维盐和氯虫苯甲酰胺复配组合在二者质量比介于2∶8~7∶3范围内表现增效作用,以3∶7时增效作用最大,共毒系数CTC为173。基于该比例加工获得10%甲维盐·氯虫苯甲酰胺水分散粒剂,并以此开展田间防治草地贪夜蛾效果评价,结果表明,施药浓度高于有效剂量37.5 g/hm^2时,药后3、14 d对草地贪夜蛾的防效分别达到88%和84%以上,表现出良好的速效性和持效性。甲维盐和氯虫苯甲酰胺以质量比3∶7混配是防治草地贪夜蛾的良好配方。 展开更多
关键词 甲维盐 氯虫苯甲酰胺 草地贪夜蛾 增效 防效
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基于Sobol’法的孤岛微电网潮流全局灵敏度分析 被引量:27
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作者 何琨 严正 +1 位作者 徐潇源 王晗 《电力系统自动化》 EI CSCD 北大核心 2018年第14期99-106,共8页
随着可再生能源发电在微电网中的渗透率不断提高,微电网运行的不确定性显著增加,有必要准确评估输入变量对微电网状态的影响,以提高系统的运行控制水平。计及孤岛微电网中分布式电源和负荷的不确定性,基于有功—频率/无功—电压的下垂... 随着可再生能源发电在微电网中的渗透率不断提高,微电网运行的不确定性显著增加,有必要准确评估输入变量对微电网状态的影响,以提高系统的运行控制水平。计及孤岛微电网中分布式电源和负荷的不确定性,基于有功—频率/无功—电压的下垂控制策略,构建了综合控制下的孤岛微电网概率潮流计算模型,并采用具有鲁棒性的自适应LM(Levenberg-Marquardt)算法进行求解。在此基础上,针对系统状态的不确定性,基于Sobol’全局灵敏度理论,建立了一种考虑源荷不确定性的孤岛微电网概率潮流灵敏度分析法,用于辨识影响系统状态的关键因素。通过对有多台分布式电源接入的33节点孤岛交流微电网系统进行仿真,获得了各输入变量的一阶灵敏度和总灵敏度,分析了输入变量对系统状态的影响,验证了所提方法的有效性。 展开更多
关键词 孤岛微电网 可再生能源 不确定性 概率潮流 Sobol’法 全局灵敏度
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Perspectives on studies on soil carbon stocks and the carbon sequestration potential of China 被引量:26
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作者 zheng JuFeng CHENG kun +6 位作者 PAN GenXing Pete SMITH LI LianQing ZHANG XuHui zheng JinWei HAN XiaoJun DU YanLing 《Chinese Science Bulletin》 SCIE EI CAS 2011年第35期3748-3758,共11页
Soil carbon stocks and sequestration have been given a lot of attention recently in the study of terrestrial ecosystems and global climate change.This review focuses on the progress made on the estimation of the soil ... Soil carbon stocks and sequestration have been given a lot of attention recently in the study of terrestrial ecosystems and global climate change.This review focuses on the progress made on the estimation of the soil carbon stocks of China,and the characterization of carbon dynamics of croplands with regard to climate change,and addresses issues on the mineralization of soil organic carbon in relation to greenhouse gas emissions.By integrating existing research data,China's total soil organic carbon(SOC) stock is estimated to be 90 Pg and its inorganic carbon(SIC) stock as 60 Pg,with SOC sequestration rates in the range of 20-25 Tg/a for the last two decades.An estimation of the biophysical potential of SOC sequestration has been generally agreed as being 2 Pg over the long term,of which only 1/3 could be attainable using contemporary agricultural technologies in all of China's croplands.Thus,it is critical to enhance SOC sequestration and mitigate climate change to improve agricultural and land use management in China.There have been many instances where SOC accumulation may not induce an increased amount of decomposition under a warming scenario but instead favor improved cropland productivity and ecosystem functioning.Furthermore,unchanged or even decreased net global warming potential(GWP) from croplands with enhanced SOC has been reported by a number of case studies using life cycle analysis.Future studies on soil carbon stocks and the sequestration potential of China are expected to focus on:(1) Carbon stocks and the sequestration capacity of the earths' surface systems at scales ranging from the plot to the watershed and(2) multiple interface processes and the synergies between carbon sequestration and ecosystem productivity and ecosystem functioning at scales from the molecular level to agro-ecosystems.Soil carbon science in China faces new challenges and opportunities to undertake integrated research applicable to many areas. 展开更多
关键词 土壤碳储量 固碳潜力 中国 全球气候变化 陆地生态系统 生态系统生产力 温室气体排放 土地使用管理
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Management of granulomatous lobular mastitis: an international multidisciplinary consensus(2021 edition) 被引量:22
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作者 Qian-Qian Yuan Shu-Yuan Xiao +63 位作者 Omar Farouk Yu-Tang Du Fereshte Sheybani Qing Ting Tan Sami Akbulut Kenan Cetin Afsaneh Alikhassi Rami Jalal Yaghan Irmak Durur-Subasi Fatih Altintoprak Tae Ik Eom Fatih Alper Mustafa Hasbahceci David Martínez-Ramos Pelin Seher Oztekin Ava Kwong Cedric W.Pluguez-Turul Kirstyn EBrownson Shirish Chandanwale Mehran Habib Liu-Yi Lan Rui Zhou Xian-Tao Zeng Jiao Bai Jun-Wen Bai Qiong-Rong Chen Xing Chen Xiao-Ming Zha Wen-Jie Dai Zhi-Jun Dai Qin-Yu Feng Qing-Jun Gao Run-Fang Gao Bao-San Han Jin-Xuan Hou Wei Hou Hai-Ying Liao Hong Luo zheng-Ren Liu Jing-Hua Lu Bin Luo Xiao-Peng Ma Jun Qian Jian-Yong Qin Wei Wei Gang Wei Li-Ying Xu Hui-Chao Xue Hua-Wei Yang Wei-Ge Yang Chao-Jie Zhang Fan Zhang Guan-Xin Zhang Shao-kun Zhang Shu-Qun Zhang Ye-Qiang Zhang Yue-Peng Zhang Sheng-Chu Zhang Dai-Wei Zhao Xiang-Min zheng Le-Wei zheng Gao-Ran Xu Wen-Bo Zhou Gao-Song Wu 《Military Medical Research》 SCIE CAS CSCD 2022年第4期389-403,共15页
Granulomatous lobular mastitis(GLM) is a rare and chronic benign inflammatory disease of the breast. Difficulties exist in the management of GLM for many front-line surgeons and medical specialists who care for patien... Granulomatous lobular mastitis(GLM) is a rare and chronic benign inflammatory disease of the breast. Difficulties exist in the management of GLM for many front-line surgeons and medical specialists who care for patients with inflammatory disorders of the breast. This consensus is summarized to establish evidence-based recommendations for the management of GLM. Literature was reviewed using PubMed from January 1, 1971 to July 31, 2020. Sixty-six international experienced multidisciplinary experts from 11 countries or regions were invited to review the evidence.Levels of evidence were determined using the American College of Physicians grading system, and recommendations were discussed until consensus. Experts discussed and concluded 30 recommendations on historical definitions,etiology and predisposing factors, diagnosis criteria, treatment, clinical stages, relapse and recurrence of GLM. GLM was recommended as a widely accepted definition. In addition, this consensus introduced a new clinical stages and management algorithm for GLM to provide individual treatment strategies. In conclusion, diagnosis of GLM depends on a combination of history, clinical manifestations, imaging examinations, laboratory examinations and pathology.The approach to treatment of GLM should be applied according to the different clinical stage of GLM. This evidencebased consensus would be valuable to assist front-line surgeons and medical specialists in the optimal management of GLM. 展开更多
关键词 Granulomatous mastitis Granulomatous lobular mastitis Idiopathic granulomatous mastitis DIAGNOSIS Treatment
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马来酸依那普利叶酸片对伴有H型高血压的不稳定型心绞痛患者血清炎性因子及心功能的影响 被引量:24
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作者 罗羽慧 梅霞 +3 位作者 柳亚敏 崔坤 郑向清 柳明云 《重庆医学》 CAS 2018年第19期2560-2563,共4页
目的探讨马来酸依那普利叶酸片对伴有H型高血压的不稳定型心绞痛患者血清炎性因子及心功能的影响。方法将2014年1月至2015年12月该院198例H型高血压合并不稳定型心绞痛的患者分为对照组和观察组,对照组给予依那普利片口服,观察组给予马... 目的探讨马来酸依那普利叶酸片对伴有H型高血压的不稳定型心绞痛患者血清炎性因子及心功能的影响。方法将2014年1月至2015年12月该院198例H型高血压合并不稳定型心绞痛的患者分为对照组和观察组,对照组给予依那普利片口服,观察组给予马来酸依那普利叶酸片口服,疗程12个月,比较治疗前后两组患者血压、血清同型半胱氨酸(Hcy)水平、炎性因子水平及心功能的改变。结果治疗12个月后,两组收缩压及舒张压差异无统计学意义(P>0.05);观察组血清Hcy、C-反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)及基质金属蛋白酶-9(MMP-9)、心脏指数(CI)及心输出量(CO)显著低于对照组(P<0.05),但左室射血分数(LVEF)与对照组比较差异无统计学意义(P>0.05)。结论马来酸依那普利叶酸片可显著减少H型高血压合并不稳定型心绞痛患者血清炎性因子水平,改善患者心功能。 展开更多
关键词 高血压 心绞痛 不稳定型 H型高血压 马来酸依那普利叶酸片 炎性因子 心功能
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