期刊文献+
共找到330篇文章
< 1 2 17 >
每页显示 20 50 100
Study on Ecological Change Remote Sensing Monitoring Method Based on Elman Dynamic Recurrent Neural Network
1
作者 Zhen Chen Yiyang Zheng 《Journal of Geoscience and Environment Protection》 2024年第4期31-44,共14页
In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to t... In this paper, Hailin City of Heilongjiang Province, China is taken as the research area. As an important city in Heilongjiang Province, China, the sustainable development of its ecological environment is related to the opening up, economic prosperity and social stability of Northeast China. In this paper, the remote sensing ecological index (RSEI) of Hailin City in recent 20 years was calculated by using Landsat 5/8/9 series satellite images, and the temporal and spatial changes of the ecological environment in Hailin City were further analyzed and the influencing factors were discussed. From 2003 to 2023, the mean value of RSEI in Hailin City decreased and increased, and the ecological environment decreased slightly as a whole. RSEI declined most significantly from 2003 to 2008, and it increased from 2008 to 2013, decreased from 2013 to 2018, and increased from 2018 to 2023 again, with higher RSEI value in the south and lower RSEI value in the northwest. It is suggested to appropriately increase vegetation coverage in the northwest to improve ecological quality. As a result, the predicted value of Elman dynamic recurrent neural network model is consistent with the change trend of the mean value, and the prediction error converges quickly, which can accurately predict the ecological environment quality in the future study area. 展开更多
关键词 Remote Sensing ecological Index Long Time Series space-time change elman Dynamic Recurrent Neural Network
下载PDF
Groundwater quality and land use change in a typical karst agricultural region:a case study of Xiaojiang watershed,Yunnan 被引量:15
2
作者 JIANG Yongjun YUAN Daoxian +3 位作者 XIE Shiyou LI Linli ZHANG Gui HE Raosheng 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期405-414,共10页
Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004... Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show: (1) There were obvious temporal and spatial changes of groundwater quality during the past 22 years. (2) Concentrations of NH4^+, SO4^2- , NO3, NO2^-, Cl^- and the pH value, total hardness, total alkalinity increased significantly, in which NH4^2-, NO3, and NO2^- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. (3) Oppositely, Ca^2+ and HCO3^- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change. 展开更多
关键词 groundwater quality space-time change land use change typical karst agricultural region GIS Xiaojiang watershed
下载PDF
Biochemical changes in phenols,flavonoids,tannins,vitamin E,β-carotene and antioxidant activity during soaking of three white sorghum varieties 被引量:7
3
作者 Abd El-Moneim MR Afify Hossam S El-Beltagi +1 位作者 Samiha M Abd El-Salam Azza A Omran 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第3期203-209,共7页
Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilav... Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking. 展开更多
关键词 SORGHUM SOAKING Total PHeNOLS FLAVONOIDS TANNINS Vitamin e Β-CAROTeNe Antioxidant activity Phenolic acids Flavonoid components Biochemical change
下载PDF
Vitamin E ameliorates aflatoxin-induced biochemical changes in the testis of mice 被引量:2
4
作者 R.J.Verma Anita Nair 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第4期305-309,共5页
Aim: To assess the effect of aflatoxin on biochemical changes in the testis of mice and the possibility of ameliorationby vitamin E treatment. Methods: Adult male albino mice were orally administered with 25 or 50μg ... Aim: To assess the effect of aflatoxin on biochemical changes in the testis of mice and the possibility of ameliorationby vitamin E treatment. Methods: Adult male albino mice were orally administered with 25 or 50μg of aflatoxin/animal/day (750 or 1500 μg/kg body weight) for 45 days. The testis was isolated and processed for biochemical anal-ysis. Results; There was a significant, dose-dependent reduction in DNA, RNA, protein, sialic acid contents andthe activities of succinic dehydrogenase, adenosine triphosphatase and alkaline phosphatase in the testis of aflatoxin-treated mice as compared to the vehicle control. However, the acid phosphatase activity was significantly increased inthe aflatoxin-treated mice. Vitamin E (2 mg/animal/day) treatment significantly ameliorated the aflatoxin-inducedchanges, except the acid and alkaline phosphatase activities in the high dose group. Conclusion; Vitamin E treat-ment ameliorates the aflatoxin-induced changes in the testis of mice. (Asian J Androl 2001 Dec; 3: 305 - 309) 展开更多
关键词 AFLATOXIN vitamin e TeSTIS biochemical changes
下载PDF
Distribution Prediction of Suitable Growth Area for Eucommia ulmoides in China under Climatic Change Background 被引量:3
5
作者 Yang Liu 《Meteorological and Environmental Research》 CAS 2013年第8期21-24,共4页
[ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of ... [ Objective] The research aimed to study distribution prediction of suitable growth area for Eucommia ulmoides in China under climatic change background. [ Method] By using the maximum entropy model and many kinds of climate change scenarios, we predicted current and future distribution pattems of suitable growth area for Eucommia ulmoides in China and its change process. [ Result ] At present, highly suitable growth area of E. ulmoides mainly distributed in Sichuan, Shaanxi and Chongqing, Under climate change background, total suitable growth areas in future three decades all drastically reduced when compared with that at present. It was noteworthy that moderately and highly suitable growth areas of wild E. ulmoides all disappeared, and junction between Shaanxi and Gansu and Taibai Mountain would be stable suitable growth area of wild E. ulmoides. [ Condusioa] The research could provide useful reference data for investigation, protection and sustainable development of the wild E. ulmoides resources. 展开更多
关键词 e. ulmoides Suitable growth area Climate change The maximum entropy model Distribution prediction China
下载PDF
Assessment of Ecological Risk to Land Use in Liaoning Province Based on Climate Change 被引量:3
6
作者 SUN Yun-peng1,2 1. College of City and Environment,Liaoning Normal University,Dalian 116029,China 2. Tangshan Teachers College,Tangshan 063000,China 《Asian Agricultural Research》 2010年第4期47-51,56,共6页
Based on the climatic data and other statistics of climatic data of 54 meteorological stations from 1956 to 2005 in Liangning Province,the annual and seasonal light,heat and water and the like major elements of climat... Based on the climatic data and other statistics of climatic data of 54 meteorological stations from 1956 to 2005 in Liangning Province,the annual and seasonal light,heat and water and the like major elements of climatic resources are diagnosed and analyzed by using the method of linear climate trend rate. The results show that warming trend is 0.25 ℃/10 a,the precipitation decrease gradually by 2.2 mm/a and the decreasing trend of solar radiation and hours of sunshine is not dramatic. The overall climate change trend is warming and drying,featuring "significantly increased temperature,the decreased precipitation and sunshine". These features are significant in autumn,thus leading to the trend of moving west and retreating east of the phenology boundaries. The results of scenario analysis on ecological security show that the ecological risk is spreading rapidly from the northwest to the east and to the south and form the southeastern and southern coastal line to the inland;different ecological land-use system have different ecological fragility. Specifically,the bare land and low coverage grassland have highest ecological vulnerability,while the forest and paddy filed have lowest ecological vulnerability. Therefore,suggestions on the ecological land use are put forward in terms of maintaining the overall ecological land use balance,saving water and adapting to climate change. 展开更多
关键词 Global CLIMATe change LAND use SCeNARIO analysis e
下载PDF
Space-time analysis of the changing patterns of population pressure on the ecological environment in China 被引量:1
7
作者 Dongqi Sun Jinliang Jiang +2 位作者 Jianbin Xu Liang Zhou Yi Hu 《Chinese Journal of Population,Resources and Environment》 2015年第4期341-348,共8页
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat... This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality. 展开更多
关键词 Chinese POPULATION eCO-eNVIRONMeNT eCO-eNVIRONMeNTAL pressure changING TReND space-time analysis
下载PDF
Effect of Decadal Changes in Air-Sea Interaction on the Climate Mean State over the Tropical Pacific 被引量:3
8
作者 FANG Xiang-Hui ZHENG Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期400-405,共6页
Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection an... Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade. 展开更多
关键词 air-sea interaction eP e1 Nifio CP e1 Nifio La Nina-like mean state change
下载PDF
Preliminary results on a near-real-time rock slope damage monitoring system based on relative velocity changes following the September 5,2022 M_(S) 6.8 Luding,China earthquake 被引量:1
9
作者 Fan Xie Chen Liang +5 位作者 Shigui Dai Bo Shao Huibao Huang Jinhui Ouyang Li Li Eric Larose 《Earthquake Research Advances》 CSCD 2023年第1期31-36,共6页
Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we pr... Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we present a rapid damage assessment on three slow-moving rock slopes by measuring dv/v decrease caused by the 2022 M_(S) 6.8 Luding earthquake in Southwest China.By applying the stretching method to the cross-correlated seismic wavefields between sensors installed on each slope,we obtain earthquake-induced dv/v decreases of~2.1%,~0.5%,and~0.2%on three slopes at distances ranging from~86 to~370 km to the epicenter,respectively.Moreover,based on seismic data recorded by 16 sensors deployed on the rock slope at a distance of~370 km away from the epicenter,a localized dv/v decease region was observed at the crest of the slope by calculating the spatial dv/v images before and after the earthquake.We also derive an empirical in situ stress sensitivity of -7.29×10^(-8)/Pa by relating the dv/v change to the measured peak dynamic stresses.Our results indicate that a rapid dv/v assessment not only can help facilitate on-site emergency response to earthquakeinduced secondary geological disasters but also can provide a better understanding of the subsurface geological risks under diverse seismic loadings. 展开更多
关键词 Relative velocity change Rock slope damage Luding earthquake space-time evolution
下载PDF
Response of fuzzy clustering on different threshold determination algorithms in spectral change vector analysis over Western Himalaya, India 被引量:2
10
作者 SINGH Sartajvir TALWAR Rajneesh 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1391-1404,共14页
Abstract: Change detection is a standard tool to extract and analyze the earth's surface features from remotely sensed data. Among the different change detection techniques, change vector analysis (CVA) have an ex... Abstract: Change detection is a standard tool to extract and analyze the earth's surface features from remotely sensed data. Among the different change detection techniques, change vector analysis (CVA) have an exceptional advantage of discriminating change in terms of change magnitude and vector direction from multispectral bands. The estimation of precise threshold is one of the most crucial task in CVA to separate the change pixels from unchanged pixels because overall assessment of change detection method is highly dependent on selected threshold value. In recent years, integration of fuzzy clustering and remotely sensed data have become appropriate and realistic choice for change detection applications. The novelty of the proposed model lies within use of fuzzy maximum likelihood classification (FMLC) as fuzzy clustering in CVA. The FMLC based CVA is implemented using diverse threshold determination algorithms such as double-window flexible pace search (DFPS), interactive trial and error (T&E), and 3x3-pixel kernel window (PKW). Unlike existing CVA techniques, addition of fuzzy clustering in CVA permits each pixel to have multiple class categories and offers ease in threshold determination process. In present work, the comparative analysis has highlighted the performance of FMLC based CVA overimproved SCVA both in terms of accuracy assessment and operational complexity. Among all the examined threshold searching algorithms, FMLC based CVA using DFPS algorithm is found to be the most efficient method. 展开更多
关键词 change vector analysis (CVA) Fuzzymaximum likelihood classification (FMLC) Double-window flexible pace search (DFPS) Interactive trialand error (T&e Pixel kernel window (PKW)
下载PDF
Biochemical and Morphological Changes in the Lenses of Selenium and/or Vitamin E Deficient Rats 被引量:1
11
作者 CAI QIU-YIN CHEN XIAO-SHU +7 位作者 ZHU LIAN-ZHEN XUE AN-NA LI WEN-XIAN WANG SHU-QIN PIAO JIAN-HUA LI JIE SUN CUN-PU WU KE AND CONG JIAN-BO(Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine, 29 Nan Wet Road, Beijing 100050, Chin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第2期109-115,共7页
The activities of glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R),superoalde dismutase (SOD) and the contents of malondialdehyde (MDA) and free radicals were measured, and the morphological changes wer... The activities of glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R),superoalde dismutase (SOD) and the contents of malondialdehyde (MDA) and free radicals were measured, and the morphological changes were observed in the lens of control rats, selenium-deficient (SeD) and/or vitamin E deficient (VED) rats. The activities of GSH-Px in the lens of SeD rats decreased significantly. The GSH-Px activities of lens were positively related to erythrocytes selenium level. There was a free radical at g = 2.0015 in the rat lens of all groupe, but the content of free radicals in the lens of SeD group was significantly higher than that of the control group. The free radical content of lens was negatively related to erythrocytes selenium level, as well as the GSH-Px activities in the lens. In vitro, ultraviolet radiation caused the generation of another kind of free radical (g = 2.0097) in the lens of all groups, but the amount of the free radical in the lens of the SeD group was also significantly higher than that of the control group. The activities of SoD and GSSG-R in VED rat lens were significantly decreased. The amount of MDA in the lens of SeD and/or VED rats were significantly increased. The results showed that the decrease of antioaldative capability in the lenses of SeD and/or VED rats accelerated the lipid peroxidation and generation of free radicals. Although only early morphological changes in SeD and/or VED rat lens were observed, it is considered that selenium and vitamin E deficiency may be involved in the occurrence of cataract 展开更多
关键词 ReS GSH Biochemical and Morphological changes in the Lenses of Selenium and/or Vitamin e Deficient Rats
下载PDF
INDEX OF DIRECTION CHANGE OF ZONALLY AVERAGED WIND AND CHANGE OF SEASON
12
作者 朱敏 徐建霞 张铭 《Journal of Tropical Meteorology》 SCIE 2011年第2期128-135,共8页
In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and season... In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and seasonal variation. The first four modes can be obtained by EOF expansion of the zonally averaged WI. The first mode reveals the basic spatial distribution of the annually averaged WI. The second mode reflects the quasi-harmonic parts of the WI deviations. Tropical, subtropical and extratropical monsoon areas can be clearly reflected by this mode. The third mode reflects the non-harmonic parts of the WI deviations. It shows the so-called February reverse in stratospheric atmosphere as well as the asymmetric seasonal changes from spring to fall and from fall to spring due to both the land-sea distribution contrast between the Northern and Southern Hemispheres and the nonlinear effect of atmospheric and ocean fluids. The fourth mode reveals the northward advancing of the global reversed wind fields from spring to summer and their southward withdrawal from summer to autumn. 展开更多
关键词 Wind Direction change Index (WI) empirical Orthogonal Function eOF) four-dimensional space-time changes February stratospheric reverse
下载PDF
Factors for the Major Changes in the English Language
13
作者 Lu Ling, Dept of Foreign Languages, Fuyang Teachers College, Fuyang 236032 《阜阳师范学院学报(社会科学版)》 2001年第1期42-44,共3页
本文阐述了引起英语变迁的历史因素-罗马人,条顿人,诺尔曼人的四次入侵;以及音变因素-e音的丢失和元音大转移。此外,印刷业的发展加速了拼写的标准化,十六、十七世纪英国文艺复兴极大地丰富了英语词汇。
关键词 英语拼写 语言变迁 历史 音变 e 元音 文艺复兴 英语 词汇 印刷业 侵略 罗马人 条顿人 诺尔曼人
下载PDF
Duncan-Chang E-υ模型在ADINA软件中的开发与应用 被引量:3
14
作者 陈志波 朱俊高 陈浩锋 《武汉理工大学学报(交通科学与工程版)》 2010年第6期1280-1283,1288,共5页
ADINA软件具有计算速度快、精度高和前后处理简单方便的优点,广泛应用于各类工程领域.然而,ADINA软件中没有岩土工程领域常用的Duncan-Chang模型.以土工数值分析中广泛应用的Duncan-Chang E-υ模型为例,介绍了ADINA软件中进行本构模型... ADINA软件具有计算速度快、精度高和前后处理简单方便的优点,广泛应用于各类工程领域.然而,ADINA软件中没有岩土工程领域常用的Duncan-Chang模型.以土工数值分析中广泛应用的Duncan-Chang E-υ模型为例,介绍了ADINA软件中进行本构模型二次开发的方法,并给出了模型开发的方法和步骤.基于ADINA软件,以Duncan-Chang E-υ模型对某土石坝工程填筑过程进行了三维有限元计算,根据计算成果对坝体竣工期位移变形规律进行了分析. 展开更多
关键词 ADINA DUNCAN-chang e-υ模型 二次开发 土石坝 三维有限元
下载PDF
慢性荨麻疹患者血清PAF、抗-CCD IgE水平变化及临床意义分析
15
作者 李椅云 毕超 +2 位作者 梁艳华 廖子青 梁碧华 《中国卫生标准管理》 2024年第18期75-78,共4页
目的探讨慢性荨麻疹患者血清血小板活化因子(platelet activating factor,PAF)、抗交叉反应性糖类决定簇免疫球蛋白E(anti-cross reactive carbohydrate determinants immunoglobulin E,抗-CCD IgE)水平变化及临床意义,为临床诊断及病... 目的探讨慢性荨麻疹患者血清血小板活化因子(platelet activating factor,PAF)、抗交叉反应性糖类决定簇免疫球蛋白E(anti-cross reactive carbohydrate determinants immunoglobulin E,抗-CCD IgE)水平变化及临床意义,为临床诊断及病情程度、预后评估提供参考依据。方法选取2021年5月—2023年5月广州市皮肤病防治所收治的100例慢性荨麻疹患者,根据荨麻疹活动评分分为轻度组(n=41)、中度组(n=35)和重度组(n=24)。采集患者空腹静脉血,通过酶联免疫吸附法测定血清PAF水平,通过斑点免疫印迹法测定抗-CCD IgE、过敏原特异性免疫球蛋白E(specific immunoglobulin E,sIgE)。比较不同病情程度慢性荨麻疹患者血清PAF水平,分析慢性荨麻疹患者血清PAF水平与荨麻疹活动评分相关性,比较不同临床特征慢性荨麻疹患者抗-CCD IgE阳性率。结果中度组、重度组患者血清PAF水平高于轻度组,重度组患者血清PAF水平高于中度组,差异有统计学意义(P<0.05)。Pearson相关分析结果显示,慢性荨麻疹患者血清PAF水平与荨麻疹活动评分呈正相关性(r=0.491,P<0.001)。年龄≥45岁、重度病情、sIgE阳性患者抗-CCD IgE阳性率高于年龄<45岁、轻度病情、sIgE阴性患者,差异有统计学意义(P<0.05)。抗-CCD IgE阳性患者中过敏原阳性最高的为尘螨组合(66.67%),其次为蟑螂、螃蟹、普通豚草,分别为55.56%、44.44%和44.44%。结论慢性荨麻疹患者血清PAF水平与病情密切相关,且抗-CCD IgE水平与sIgE水平有一定关系,抗-CCD IgE阳性表达情况对sIgE试验存在一定干扰,分析试验结果时应考虑抗-CCD IgE的影响。 展开更多
关键词 慢性荨麻疹 抗交叉反应性糖类决定簇免疫球蛋白e 血小板活化因子 免疫球蛋白e 水平变化 临床意义
下载PDF
Chang'e 4 Lands at the Far Side of the Moon 被引量:1
16
作者 CAI Jinman 《Aerospace China》 2018年第4期63-63,共1页
Chang’e 4 began its travel to the moon at 02:23 Beijing time on December 8,2018 atop a LM-3B launch vehicle from the Xichang Satellite Launch Center.After separated from the carrier rocket,Chang’e 4 entered the Eart... Chang’e 4 began its travel to the moon at 02:23 Beijing time on December 8,2018 atop a LM-3B launch vehicle from the Xichang Satellite Launch Center.After separated from the carrier rocket,Chang’e 4 entered the Earth-moon transfer orbit with perigee of 200 km and apogee of 420 000 km. 展开更多
关键词 change Lands MOON
下载PDF
Chang'e 3 Lander Completed Mechanical Test
17
《Aerospace China》 2012年第4期23-23,共1页
Aground firing test of the Chang'e 3 lander was conducted recently to check the mechanical performance of the spacecraft. The test was vital before the propulsion system test of the Chang'e 3 lander and was al... Aground firing test of the Chang'e 3 lander was conducted recently to check the mechanical performance of the spacecraft. The test was vital before the propulsion system test of the Chang'e 3 lander and was also a very important precondition to verify whether the propulsion system design could meet the requirements for in-orbit operation. 展开更多
关键词 TeST very change 3 Lander Completed Mechanical Test
下载PDF
Correlation analysis of human papillomavirus E6/E7 mRNA detection with diagnosis,prognosis and recurrence risk in patients with cervical epithelioma
18
作者 Ling-Li Zhang Ming-Yan Du +5 位作者 Xin Du Jie Duan Dong-Mei Yao Jing Jing Chun Feng Lin Song 《World Journal of Clinical Cases》 SCIE 2024年第20期4146-4153,共8页
BACKGROUND Cervical intraepithelial neoplasia(CIN)is an important precursor of cervical cancer.Early detection and treatment can reduce the incidence of cervical cancer.AIM To investigate the detection rate of human p... BACKGROUND Cervical intraepithelial neoplasia(CIN)is an important precursor of cervical cancer.Early detection and treatment can reduce the incidence of cervical cancer.AIM To investigate the detection rate of human papillomavirus(HPV)E6/E7 mRNA in cervical tissue of patients with different types of epithelial cell neoplasia(CIN)and its relationship with CIN progression and diagnosis.METHODS One hundred women with HPV infection detected by cervical exfoliation cytology between January 2022 and January 2023 were retrospectively selected.These patients were graded CIN based on colposcopy and cervical pathology.The positive expression rates of HPV E6/E7 mRNA and HPV[polymerase chain reaction(PCR)-reverse dot crossing]were compared among all groups.Patients with HPV E6/E7 mRNA expression in the grade 1 CIN group were followed up for 1 yr.The relationship between atypical squamous epithelium and high malignant epithelial neoplasia was investigated by univariate and multivariate analysis.RESULTS The diagnostic sensitivity,specificity,and sensitivity of PCR-reverse point hybrid ization technology for secondary CIN were 70.41%,70.66%,and 0.714,respectively.Sensitivity and specificity for secondary CIN were 752%and 7853%,respectively,the area under the curve value was 0.789.Logistic Multifactorial model analysis revealed that the HPV positive rates and the HPV E6/E7 mRNA positive rates were independent risk factors of CIN grade I(P<0.05).In CIN grade I patients with positive for HPV E6/E7 mRNA,in its orientation to grade CIN patients,in its orientation to grade CIN patients,at 69.2%,compared with patients negative for HPV E6/E7 mRNA(30.8%),significant difference(P<0.05).CONCLUSION HPV E6/E7 mRNA and HPV(PCR-reverse dot hybrid)positive expression have a close relationship with CINgrade disease progression and is an independent risk factor for high-grade CIN lesions. 展开更多
关键词 Cervical epithelial neoplasia Human papilloma change with virus e6/e7 mRNA Cervical cancer Correlation analysis
下载PDF
Chang'e 5 Undergoing Thermal Test
19
作者 QI Guangming LI Zhenwei CAI Xiaomao 《Aerospace China》 2017年第1期59-59,共1页
Chang’e 5 probe has entered its critical phase of AIT.Units,except the lander,are undergoing thermal test.The flight model of Chang’e 5 is composed of an orbiter,a return capsule,a lander and an ascent unit.The ther... Chang’e 5 probe has entered its critical phase of AIT.Units,except the lander,are undergoing thermal test.The flight model of Chang’e 5 is composed of an orbiter,a return capsule,a lander and an ascent unit.The thermal tests on the ascent unit,the lander-as- 展开更多
关键词 TeST change 5 Undergoing Thermal Test
下载PDF
基于CIM/E的配电网模型异动管理 被引量:12
20
作者 钱静 崔立忠 +5 位作者 尚学伟 陈鑫 郝泽赟 高习斌 王玲 钱传伟 《电网技术》 EI CSCD 北大核心 2014年第12期3516-3521,共6页
配电自动化系统建模对外部系统依赖性强、信息源头多、形式多样、需要流程管理,因此带来了信息交互标准性、完整性、时效性差等问题,为此,提出基于CIM/E(高效模型描述规范语言)的配网模型异动管理方案。分析了CIM/E作为模型和模式数据... 配电自动化系统建模对外部系统依赖性强、信息源头多、形式多样、需要流程管理,因此带来了信息交互标准性、完整性、时效性差等问题,为此,提出基于CIM/E(高效模型描述规范语言)的配网模型异动管理方案。分析了CIM/E作为模型和模式数据描述语言的特点,以及应用在配网模型管理中的可行性和优势;探讨了CIM/E在模型导入、导出、模型抽取、异动分析、增量投退、版本管理技术上的具体运用;并提出以异动单为最小单元的配网模型异动管理方法。介绍了相关软件产品的实际用例,基于CIM/E和异动单的配网模型管理,可以部分解决配网信息集成准确性、时效性方面的问题,并可满足模型管理的原子性、完整性的需求。 展开更多
关键词 智能配电网 IeC 61970/61968标准 模型异动管理 CIM/e 异动单 信息集成
下载PDF
上一页 1 2 17 下一页 到第
使用帮助 返回顶部