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网球运动早期专项技术训练之我见 被引量:7
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作者 郑向千 《湖南商学院学报》 2007年第2期118-119,共2页
针对网球运动早期专项技术训练的一般规律,结合本人从事网球教学训练的实践经验,提出网球运动员早期专项技术训练,应从培养技术动作的规范化,注重技术动作可迁移性的特点以及加强步法训练几方面入手,注重基本功,循序渐进,同时,对训练中... 针对网球运动早期专项技术训练的一般规律,结合本人从事网球教学训练的实践经验,提出网球运动员早期专项技术训练,应从培养技术动作的规范化,注重技术动作可迁移性的特点以及加强步法训练几方面入手,注重基本功,循序渐进,同时,对训练中常见问题提出建议。 展开更多
关键词 网球运动 早期 专项技术训练
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第二语言学习“越早越好”研究的定性元分析 被引量:8
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作者 黄怀飞 《天津外国语大学学报》 2013年第5期52-56,共5页
借助定性元分析的方法,对比第二语言环境和外语环境下英语学习"越早越好"的研究报告,分析造成研究结果存在分歧的原因,以此为基础提出自己的观点:汉语环境下英语学习越早越好只是一种主观的良好愿望,应该客观看待英语学习低... 借助定性元分析的方法,对比第二语言环境和外语环境下英语学习"越早越好"的研究报告,分析造成研究结果存在分歧的原因,以此为基础提出自己的观点:汉语环境下英语学习越早越好只是一种主观的良好愿望,应该客观看待英语学习低龄化的现象。 展开更多
关键词 第二语言学习 “越早越好”假设 定性元分析
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Rapid Identification of Bacterial Species Associated with Bronchiectasis via Metagenomic Approach 被引量:5
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作者 YANG Dong Hong ZHANG Yuan Yuan +5 位作者 DU Peng Cheng XU Li WANG Hai Yin HAN Na CHEN Chen GAO Zhan Cheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第11期898-901,共4页
Bronchiectasis is a chronic lung disorder and a number of bacterial pathogens are involved.However,30%-40% of sputum and purulent samples in good quality failed to grow any pathogenic bacteria,making it difficult to c... Bronchiectasis is a chronic lung disorder and a number of bacterial pathogens are involved.However,30%-40% of sputum and purulent samples in good quality failed to grow any pathogenic bacteria,making it difficult to confirm the pathogen.In this study,we collected bronchoalveolar lavage fluid from a bronchiectasis patient undergoing acute exacerbation,and sent for 16 S rDNA pyrosequencing by a 454 GS Junior machine.Metagenomic analysis showed the composition of bacterial community in sample was complex.More than a half of reads(51.3%) were from Pseudomonas aeruginosa.This result was corresponding with the culture result but came out 2 d earlier,which is meaningful for early diagnosis and treatment.The detection with 16 S rDNA pyrosequencing technology is more sensitive and rapid than routine culture,and can detect the co-infection or symbiosis in airway,giving us a novel and convenient approach to perform rapid diagnosis. 展开更多
关键词 pathogenic exacerbation meaningful earlier Junior giving airway routine Species Associated
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Topology optimization of 3D shell structures with porous infill 被引量:5
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作者 Anders Clausen Erik Andreassen Ole Sigmund 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第4期778-791,共14页
This paper presents a 3D topology optimization approach for designing shell structures with a porous or void interior. It is shown that the resulting structures are significantly more robust towards load perturbations... This paper presents a 3D topology optimization approach for designing shell structures with a porous or void interior. It is shown that the resulting structures are significantly more robust towards load perturbations than completely solid structures optimized under the same conditions. The study indicates that the potential benefit of using porous structures is higher for lower total volume fractions.Compared to earlier work dealing with 2D topology optimization, we found several new effects in 3D problems. Most notably, the opportunity for designing closed shells significantly improves the performance of porous structures due to the sandwich effect. Furthermore, the paper introduces improved filter boundary conditions to ensure a completely uniform coating thickness at the design domain boundary. 展开更多
关键词 porous shells topology interior perturbations opportunity dealing earlier stiffness struc
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China's meat and grain imports during 2000–2012 and beyond: A comparative perspective 被引量:4
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作者 YU Wu-sheng CAO Li-juan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第6期1101-1114,共14页
This paper provides a review on China's meat trade for the 2000–2012 period and discusses its future development, with reference to China's grain trade. With marginal decreases in meat exports and slight increases ... This paper provides a review on China's meat trade for the 2000–2012 period and discusses its future development, with reference to China's grain trade. With marginal decreases in meat exports and slight increases in their imports, China's net imports of major meat products(including pork, beef, mutton and poultry but excluding meat offal) were just below 1 million tons in 2012, dwarfed by China's net imports of grains which reached 66.7 million tons in the same year. This slow growth in meat trade seems to contradict earlier expectations on increasing meat demand and imports, based upon projected shifts in consumption patterns driven by rapid per capita income growth. Several plausible explanations of this paradoxical trade pattern are offered, including mass imports of feed grains, persistent(but shrinking) gaps between Chinese and international meat prices, tariff barriers, and non-tariff measures. In the near future China may not be able to maintain such a lower profile on the world meat markets, as per capita income is projected to continue to rise and domestic production cost advantages erode due to rising labor costs. A model-based projection exercise indicates that under plausible assumptions China's meat imports may rise sharply by 2030. 展开更多
关键词 imports and beyond tariff prices capita income excluding earlier projection quota
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Western Democracy:A Democracy in Distress
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作者 HUANG YUHAO 《China Today》 2023年第5期38-40,共3页
Western experts and scholars share their opinions about Western democracy and Chinese democracy at the Second International Forum on Democracy:The Shared Human Values.THE Summit for Democracy 2023 held on March 28 in ... Western experts and scholars share their opinions about Western democracy and Chinese democracy at the Second International Forum on Democracy:The Shared Human Values.THE Summit for Democracy 2023 held on March 28 in the U.S.is the host country’s latest try to accuse other countries of being authoritarian,based on its own standard and the hegemonistic mindset.Is such an accusation well-grounded?Participants of the Second International Forum on Democracy,which concluded days earlier on March 23 in Beijing,beg to differ,including voices from some Western countries. 展开更多
关键词 DEMOCRACY FORUM earlier
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宝水(节选)
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作者 QIAO Ye 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2023年第4期335-340,共6页
"Dates ripen in July,pears in August,and persimmons in September."The months in this phrase refer to the lunar calendar.At times,however,we follow the solar calendar.For example,"The breeze at the Start... "Dates ripen in July,pears in August,and persimmons in September."The months in this phrase refer to the lunar calendar.At times,however,we follow the solar calendar.For example,"The breeze at the Start of Autumn reddens hawthorns,and the White Dew indicates the harvest of walnuts."Hawthorns and dates ripen earlier than other fruits,well explaining these two lines.Villagers start to pick hawthorns after the Start of Autumn,as I once did with Xiumei.Picking hawthorns requires certain techniques. 展开更多
关键词 VILLAGE HARVEST earlier
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A FRIEND FROM AFAR
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作者 Liang Xiao 《Beijing Review》 2023年第16期18-19,共2页
Brazilian president’s visit to China expected to raise bilateral ties to a new high If it weren’t for the flu and pneumonia, 77-year-old Brazilian President Luiz Inácio Lula da Silva’s state visit to China wou... Brazilian president’s visit to China expected to raise bilateral ties to a new high If it weren’t for the flu and pneumonia, 77-year-old Brazilian President Luiz Inácio Lula da Silva’s state visit to China would have taken place from March 26 to 31, and he would have been the first foreign head of state to be received by Chinese President Xi Jinping after Xi’s reelection earlier that month. 展开更多
关键词 VISIT BILATERAL earlier
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High production of β-glucosidase from a marine Aspergillus niger immobilized on towel gourd vegetable sponges 被引量:2
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作者 Dong-Sheng Xue Jiang-Bo Wang Shan-Jing Yao 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第8期1011-1015,共5页
To produce β-glucosidase by consecutive batch fermentation, a marine Aspergillus niger was immobilized on a natural carrier, towel gourd vegetable sponges. The immobilized mycelia were 0.15 g/g carrier with the immob... To produce β-glucosidase by consecutive batch fermentation, a marine Aspergillus niger was immobilized on a natural carrier, towel gourd vegetable sponges. The immobilized mycelia were 0.15 g/g carrier with the immobilized biomass percentage of over 95%. The immobilized mycelia possessed the long durability(22.5 days). The maximum production occurred 1.5 day earlier by the immobilized mycelia than by the free mycelia. β-Glucosidase production of five consecutive batches was over 110 U/m L. At high salinity,the activity and stability of β-glucosidase from the marine A. niger increased remarkable. Immobilizing the marine A. niger on the novel natural carrier achieved the efficient production of β-glucosidase. 展开更多
关键词 glucosidase niger vegetable batch durability earlier salinity biomass reserved producing
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Effects of Rumen Protected Methionine on Milk Yield and Milk Composition in Earlier Lactating Cow 被引量:1
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作者 SUN Manji SHAN Anshan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期30-32,共3页
A total of 12 mature healthy Holstein dairy cows of the nearly body weight (580±30) kg, milk yield (22.5±2.8) kg in the early stages of lactation were selected in this experiment. The cows were randomly ... A total of 12 mature healthy Holstein dairy cows of the nearly body weight (580±30) kg, milk yield (22.5±2.8) kg in the early stages of lactation were selected in this experiment. The cows were randomly divided into 2 groups, every group had 6 cows, every group had 6 repeats, and every repeat had 1 cow. Added 20 g protected methionine in earlier lactating cow food every day. The results showed that protected methionine increased milk yield by 10.83%, testing group milk yield was significantly different than that of control (P〈0.05); protected methionine increased milk fat by 5.98%, testing group milk fat was significantly different than that of control (P〈0.05); Milk protein increased by 2.15%, but bad insignificantly different (P〉0.05); dry matter of milk had the tendency of decrease, but had insignificant difference (P〉0.05). 展开更多
关键词 METHIONINE earlier lactating period milk yield milk composition
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Utilizing Dominant Early Maturity Genes of Sterile Line UP-3s in Hybrid Rice Breeding to Avoid High Temperature Season 被引量:1
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作者 Bihu Huang Zongbu Yan 《American Journal of Plant Sciences》 2015年第16期2596-2602,共7页
A new sterile line UP-3s, which carries the Dominant Early Maturity Gene (DEMG), was bred on the farm of University of Arkansas at Pine Bluff (UAPB). UP-3s and two check sterile lines, Jin23-A and Xie-A which do not c... A new sterile line UP-3s, which carries the Dominant Early Maturity Gene (DEMG), was bred on the farm of University of Arkansas at Pine Bluff (UAPB). UP-3s and two check sterile lines, Jin23-A and Xie-A which do not carry the Dominant Early Maturity Gene, were crossed with a group of different maturity restorer lines, PB-1R, PB-5R,PB11, PB-13R, PB-20, PB-21, PB-22R, and PB-23R. Eighteen new hybrid rice combinations of these crosses were then tested at UAPB in 2012 and 2013. The results showed that panicle differentiation (PD) of hybrids from female parent UP-3s (DEMG) crossed with the 8 male parents, were earlier than the hybrids from female parent Jin23-A or Xie-A crossed with the 8 male parents. The PD of these earlier hybrids was before Jun 25 and heading was before July 20. Early PD and heading avoided the high temperature (over 34&degC) period which usually occurs after July 20 in Arkansas. The yields of these earlier maturity hybrids with female parent UP-3s were higher than those of the late maturity hybrids thatwereF1 progeny of sterile lines Jin23-A or Xie-A (these two female parent checks with non-DEMG). These results showed that the DEMG sterile line UP-3s can be adopted in making crosses with later maturity restorer lines to obtain earlier maturity hybrids to avoid the high temperature period in Arkansas. 展开更多
关键词 earlier MATURITY DOMINANT Gene STERILE LINE Hybrid Rice Utilization BREEDING Avoid High Temperature
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Cholangiocarcinoma Arising 38 Years after Surgical Resection of Hepatocellular Carcinoma 被引量:1
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作者 Jianguo Chen Weizhong Lu +7 位作者 Lianxin Wang Yixin Zhang Nengjin Wang Yongsheng Chen Jian Zhu Hongwei Zheng Jun Yang Fei Chen 《Journal of Cancer Therapy》 2013年第5期953-956,共4页
Background: Most of the reports on tumor relapse are recurrence of the same type of tumor after months to few years of a successful initial cancer treatment. It is generally unusual and unexpected that a different typ... Background: Most of the reports on tumor relapse are recurrence of the same type of tumor after months to few years of a successful initial cancer treatment. It is generally unusual and unexpected that a different type of the second tumor occurs after several decades of the curative treatment of the original tumor. Case Presentation: We report a case of 74-year-old man with intrahepatic cholangiocarcinoma (ICC) diagnosed 38 years after curative resection of hepatocellular carcinoma (HCC). In addition to the uniqueness of longer survival and developed a new type of tumor, both the original HCC and the later occurred ICC were detected through a cancer surveillance program by screening alpha-fetoprotein (AFP) and ultrasonography of the liver for the general population and/or high risk group of people who were asymptomatic. Conclusion: This report provides evidence demonstrating occurrence of new type of tumor following initial curative therapy of the original tumor. In addition, this case report also highlights the importance of cancer surveillance program for earlier detection of the tumors to achieve a remarkably improved prognosis of the cancer patients for a prolonged cancer free survival time. 展开更多
关键词 HCC ICC Liver CIRRHOSIS Cancer SURVEILLANCE earlier Detection
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Omicron:increased transmissibility and decreased pathogenicity 被引量:1
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作者 Gábor Bálint Barbara Vörös-Horváth Aleksandar Széchenyi 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2022年第6期1865-1867,共3页
Three research papers were published recently to compare the virological properties of the Omicron variant with the earlier variants of concern(VOC).1,2,3 The SARS-CoV-2 B.1.1.529 variant,Omicron,was first detected in... Three research papers were published recently to compare the virological properties of the Omicron variant with the earlier variants of concern(VOC).1,2,3 The SARS-CoV-2 B.1.1.529 variant,Omicron,was first detected in South Africa in October 2021 and has spread rapidly;within three months,it appeared in more than 87 countries.4 During the surveillance of the epidemiological data and mutations of earlier COVID-19 variants and Omicron,significant differences were revealed mainly in the reproduction rate and hospitalization. 展开更多
关键词 OMI earlier REPRODUCTION
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第一次完整建造:维特拉消防站 被引量:2
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作者 帕特里克.舒马赫 《建筑创作》 2017年第1期147-155,146,共9页
维特拉消防站是个非常早期的项目。在它之前,扎哈赢得过香港山顶俱乐部竞赛,以及为柏林著名的库达姆大道所做的刀锋形设计的竞赛,但这些项目最终都没能实现,还是有些令人受挫的。我加入之后,我们参加了更多竞赛,虽然大部分都输了,但是... 维特拉消防站是个非常早期的项目。在它之前,扎哈赢得过香港山顶俱乐部竞赛,以及为柏林著名的库达姆大道所做的刀锋形设计的竞赛,但这些项目最终都没能实现,还是有些令人受挫的。我加入之后,我们参加了更多竞赛,虽然大部分都输了,但是我们认为这些都是很优秀的设计。 展开更多
关键词 维特 扎哈 earlier FORMAL PRAGMATIC 结构工程师 FURNITURE COMPETITION actually establishing
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超声诊断早期肝硬化人工神经网络模型的评价 被引量:2
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作者 李俏颖 段云友 +4 位作者 张莉 闫国珍 杨瑞静 曹铁生 任聃 《临床超声医学杂志》 2008年第8期517-519,共3页
目的评价人工神经网络模型在超声诊断早期肝硬化的准确性和可靠性。方法收集临床慢性肝病患者超声影像特征数据为训练样本集,以肝脏组织病理学活检作为金标准,建立超声诊断早期肝硬化人工神经网络模型;同时,将另外收集的慢性肝病患者超... 目的评价人工神经网络模型在超声诊断早期肝硬化的准确性和可靠性。方法收集临床慢性肝病患者超声影像特征数据为训练样本集,以肝脏组织病理学活检作为金标准,建立超声诊断早期肝硬化人工神经网络模型;同时,将另外收集的慢性肝病患者超声影像特征数据通过神经网络进行仿真运算,得到网络诊断输出,评价该神经网络模型应用于早期肝硬化超声影像诊断的准确性和可靠性。结果以统计学选出的参数作为输入层参数的三层人工神经网络用于超声诊断早期肝硬化的灵敏度和特异度分别为84.1%、84.6%,准确度87.9%,尤登指数0.687。结论人工神经网络模型用于超声诊断早期肝硬化具有较高的准确性,有可能为肝硬化早期诊断提供又一实用有效的手段。 展开更多
关键词 人工神经网络 肝硬化 早期 超声检查
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A New Integrable (2+1)-Dimensional Generalized Breaking Soliton Equation:N-Soliton Solutions and Traveling Wave Solutions 被引量:2
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作者 Abdul-Majid Wazwaz 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第10期385-388,共4页
In this work,we study a new(2+1)-dimensional generalized breaking soliton equation which admits the Painleve property for one special set of parameters.We derive multiple soliton solutions,traveling wave solutions,and... In this work,we study a new(2+1)-dimensional generalized breaking soliton equation which admits the Painleve property for one special set of parameters.We derive multiple soliton solutions,traveling wave solutions,and periodic solutions as well.We use the simplified Hirotas method and a variety of ansatze to achieve our goal. 展开更多
关键词 breaking soliton equations Hirota bilinear method multiple soliton solutions traveling wave solutions
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Fire Distribution of Integrated Missile-gun Air Defense System Based on Earlier Damage Criterion
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作者 王艳霞 曹建军 郭治 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第1期75-80,共6页
The fire distribution can be divided into weapon assignment and firing time scheduling. The criterion of weapon allocation is that a target with greater threat has higher priority. And the criterion of firing time sch... The fire distribution can be divided into weapon assignment and firing time scheduling. The criterion of weapon allocation is that a target with greater threat has higher priority. And the criterion of firing time scheduling is that a target can be damaged with the expected probability before a specific time. A fire distribution scheme and a program for the integrated missile-gun air defense system based on a criterion of earlier damage were presented. An example was taken to illustrate its effectiveness. 展开更多
关键词 operational research fire distribution integrated missile-gun air defense system expected damage probability earlier damage
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Microarray profiles on age-related genes in the earlier postnatal rat visual cortex
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作者 YANG Liu NIE Yu-hong +2 位作者 ZHOU Li-hua LIN Shao-chun WU Kai-li 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第10期1545-1550,共6页
Background Accumulating evidence indicates that both innate and adaptive mechanisms are responsible for the postnatal development of the mammalian visual cortex. Most of the studies, including gene expression analysis... Background Accumulating evidence indicates that both innate and adaptive mechanisms are responsible for the postnatal development of the mammalian visual cortex. Most of the studies, including gene expression analysis, were performed on the visual cortex during the critical period; few efforts were made to elucidate the molecular changes in the visual cortex during much earlier postnatal stages. The current study aimed to gain a general insight into the molecular mechanisms in the developmental process of the rat visual cortex using microarray to display the gene expression profiles of the visual cortex on postnatal days.Methods All age-matched Sprague-Dawley rats in various groups including postnatal day 0 (PO, n=20), day 10 (P10,n=15), day 20 (P20, n=15) and day 45 (P45, n=10) were sacrificed respectively. Fresh visual cortex from the binocular area (Area 17) was dissected for extraction of total RNA for microarray analyses. Taking advantage of annotation information from the gene ontology and pathway database, the gene expression profiles were systematically and globally analyzed.Results Of the 31 042 gene sequences represented on the rat expression microarray, more than 4000 of the transcripts significantly altered at days 45,20 or 10 compared to day 0. The most obvious alteration of gene expression occurred in the first ten days of the postnatal period and the genomic activities of the visual cortex maintained a high level from birth to day 45. Compared to the gene expression at birth, there were 2630 changed transcripts that shared in three postnatal periods.The up-regulated genes in most signaling pathways were more than those of the down-regulated genes.Conclusions Analyzing gene expression patterns, we provide a detailed insight into the molecular organization of the developing visual cortex in the earlier postnatal rat. The most obvious alteration of gene expression in visual cortex occurred in the first ten days. Our data were a basis to identify new relevant candidate genes that co 展开更多
关键词 microarray analysis earlier postnatal development visual cortex RAT
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Beijing’s Rich Legacy in Sound
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作者 Colin Chinnery 《Voice of Friendship》 2015年第1期35-38,共4页
Last year I embarked on a new project for which I still don’t have a satisfactory title.It started out being the Beijing Hutong Sound Project,then the Beijing Sound History Project,and now the Beijing Sonic Reenactme... Last year I embarked on a new project for which I still don’t have a satisfactory title.It started out being the Beijing Hutong Sound Project,then the Beijing Sound History Project,and now the Beijing Sonic Reenactment Project.The lineage of titles reflects the project’s conceptualization from last summer,when it first began,up until the moment earlier this year when I started realizing its potential 展开更多
关键词 earlier satisfactory HERITAGE LINEAGE UNTIL TODAY
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Pulse oximetry for screening critical congenital heart disease in newborns
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作者 陈翠莹 吴淑燕 +2 位作者 游可理 陈观娣 李志刚 《South China Journal of Cardiology》 CAS 2016年第2期55-60,66,共7页
Background Pulse oximetry screening(POS) has been proposed as an effective,noninvasive,inexpensive tool allowing earlier diagnosis of critical congenital heart disease(CCHD).However,most neonates are discharged fr... Background Pulse oximetry screening(POS) has been proposed as an effective,noninvasive,inexpensive tool allowing earlier diagnosis of critical congenital heart disease(CCHD).However,most neonates are discharged from the hospital without this evaluation in China.This study aimed at assessing the feasibility of POS for newborns in detecting CCHD in the department of obstetrics and neonatal intensive care unit(NICU).Methods POS was performed in 355 neonates born in the department of obstetrics or admitted to the NICU between January 2015 and June 2015.These neonates were divided into normal group,mild congenital heart disease group(MCHD) and CCHD group,according to the result of echocardiography or computerized tomography(CT).The gestational age,birth weight and arterial oxygen saturation(SpO_2) were compared among the three groups.The SpO_2 value and diagnosis time of the CCHD cases were classified and analyzed.Results The premature birth and low birth weight were the high risk factors of mild congenital heart disease.There was no difference(P 〉 0.05) in SpO_2 between the MCHD group and the normal group.Significant difference in the SpO_2 appeared between the CCHD group and the normal group(P 〈 0.05).Combination of POS and clinical examination can reduce the missing diagnosis rate in screening for CCHD.Conclusions POS incurs very low cost and risk of harm and is not required for special training,therefore,an effective way to identify CCHD in neonates. 展开更多
关键词 congenital screening gestational birth neonatal saturation inexpensive earlier discharged aimed
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